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8040493
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The relationship between information processing and language production.
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We explored the relationships between information processing and language in order to further the understanding of language disturbances in psychiatric patients. To assess the impact of reduced processing capacity on language, 50 undergraduates completed an interview concurrent with a category monitoring task and a control interview without a concurrent task. Syntactic complexity, verbosity, and pause patterns were all disrupted by a reduction in processing capacity. In addition, individual differences in syntactic complexity and information processing were significantly associated, even after accounting for verbal intelligence. We discuss the relevance of the results for understanding language disturbances in psychopathology and hypothesize that a reduction in processing capacity may underlie the decreased syntactic complexity, decreased verbal output, and increased pause length found in schizophrenia.
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8040492
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"Unconscious anxiety": phobic responses to masked stimuli.
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We tested the hypothesis that an unconscious preattentive perceptual analysis of phobic stimuli is sufficient to elicit human fear responses. Selected snake- and spider-fearful Ss, as well as normal controls, were exposed to pictures of snakes, spiders, flowers, and mushrooms. A separate forced-choice recognition experiment established backward masking conditions that effectively precluded recognition of experimental stimuli both for fearful and nonfearful Ss. In the main experiment, these conditions were used to compare skin conductance responses (SCRs) to masked and nonmasked phobic and control pictures among fearful and nonfearful Ss. In support of the hypotheses, snake- and spider-fearful Ss showed elevated SCRs to snake and spider pictures as compared with neutral pictures and with responses of the nonfearful Ss under both masking conditions. Ratings of valence, arousal, and dominance indicated that the fearful Ss felt more negative, more aroused, and less dominant in relation to both masked and nonmasked phobic stimuli.
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8040491
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Eye tracking dysfunction in schizophrenia: characterization of component eye movement abnormalities, diagnostic specificity, and the role of attention.
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To characterize oculomotor components and diagnostic specificity of eye tracking abnormalities in schizophrenia, we examined a large consecutively admitted series of psychotic patients and matched controls. The most common abnormality in schizophrenic patients was low gain (slow) pursuit eye movements (47% of cases). Pursuit and saccadic eye movement abnormalities were no more severe in schizophrenic Ss than in those with affective psychoses, except that high rates of catch-up saccades were unique to schizophrenic Ss (17% of cases). These findings indicate that impaired pursuit eye movements are a major cause of eye tracking impairments in schizophrenia, that tracking dysfunctions commonly occur in affective psychoses, and that markedly high rates of catch-up saccades during eye tracking may be specific to schizophrenia.
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8040490
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Clinical and cognitive effects of methylphenidate on children with attention deficit disorder as a function of aggression/oppositionality and age.
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Children diagnosed with attention deficit disorder (ADD; n = 44), ADD plus aggression/oppositionality (ADD/O; n = 34), and as not meeting ADD criteria (NC; n = 29) received methylphenidate and placebo for 21 consecutive days each. Parents and teachers rated all groups improved under medication, but teachers reported less improvement for NC than for ADD/O children. Methylphenidate and chronological age had generally similar effects in a Sternberg task: greater accuracy and speed (especially for nontargets at low memory loads), larger P3b waves of event-related potentials, more pronounced slowing of P3b latency by memory load, and a greater trend of earlier peaks for targets than for nontargets. Both methylphenidate and maturation promoted more efficient strategies involving differentiated evaluation of targets and nontargets. These results were comparable among ADD groups.
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8040489
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Measuring impulsivity and examining its relationship to delinquency.
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A multimethod, multisource assessment of impulsivity was conducted in a sample of more than 400 boys who were members of a longitudinal study of the development of antisocial behavior. Exploratory and confirmatory factor analysis of the 11 different impulsivity measures revealed two impulsivity factors: Cognitive and Behavioral. Cognitive and behavioral impulsivity had similar correlations with socioeconomic status. Cognitive impulsivity was more strongly related to IQ than was behavioral impulsivity. Behavioral impulsivity was more strongly related to delinquency at ages 10 and 12-13 than was cognitive impulsivity. Consistent with theoretical prediction, our results also indicate that behavioral impulsivity was especially related to serious delinquency that is stable over time.
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8040488
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Is the hypnotized subject lying?
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Do the verbal reports of deeply hypnotized Ss truthfully reflect their subjective experiences of hypnotic suggestions? Experiment 1 established that the electrodermal skin conductance response (SCR) provides an effective method for detecting deception in the laboratory equally well in hypnotized and nonhypnotized Ss. In Experiment 2, deeply hypnotized and simulating Ss were administered a number of hypnotic suggestions in a typical hypnotic session, without mention of deception, and were questioned about their experiences while SCR measures were recorded concurrently. Results indicate that 89% of the hypnotized Ss' reports met the criterion for truthfulness, whereas only 35% of the simulators' reports met this criterion. Implications for the theory of hypnosis are discussed.
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8040487
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Putatively psychosis-prone subjects 10 years later.
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The predictive validities of several indicators of psychosis proneness were evaluated in a 10-year longitudinal study (N = 508). As hypothesized, high scorers on the Perceptual Aberration Scale, Magical Ideation Scale, or both (n = 182), especially those who initially reported psychoticlike experiences of at least moderate deviance, exceeded control subjects (n = 153) on psychoses (revised 3rd edition of the Diagnostic and Statistical Manual of Mental Disorders), psychotic relatives, schizotypal symptoms, and psychoticlike experiences at follow up. Ss who initially scored high on the Magical Ideation Scale and above the mean on the Social Anhedonia Scale were especially deviant. The Physical Anhedonia Scale and the Impulsive Nonconformity Scale were not effective predictors of psychosis proneness.
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8040486
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Personality and disinhibitory psychopathology: alcoholism and antisocial personality disorder.
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We discuss the relation between personality factors and two adult forms of disinhibitory psychopathology--alcohol abuse or dependence and antisocial personality disorder. First, we briefly review various methodological issues relevant to research in this area. Next, we review empirical findings relating three broad-band personality trait dimensions neuroticism/emotionality, impulsivity/disinhibition, extraversion/sociability) to both alcohol abuse and dependence and antisocial personality disorder. Finally, theoretical models of the relationship between personality and each of these two disorders are presented. We conclude that although no single personality description is likely to be both a sensitive and specific indicator of either alcoholism or antisocial personality disorder, personality variables are important components of etiological models of these disorders.
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8040485
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Personality and personality disorders.
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The mental disorders that most clearly relate to personality are the personality disorders. The purpose of this article is to review the support for the hypothesis that the personality disorders of the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) represent variants of normal personality traits. We focus in particular on the efforts to identify the dimensions of personality that may underlie the personality disorders. We then illustrate the relationship of personality to personality disorders using the five-factor model, discuss conceptual issues in relating normal and abnormal personality traits, and consider methodological issues that should be addressed in future research.
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8040484
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Personality and psychopathology: a historical perspective.
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The possible links between personality psychology and psychopathology are examined with the goal of understanding the constraints that set boundaries to the possible contributions of one to the other. The reciprocal nature of these contributions is described. The historical survey looks at the early concepts of the humors and temperament, at the concept of a general vulnerability to psychosis and deviance--represented by the 19th-century concept of degeneracy--and at later typologies arising from the work of Eysenck, Freud, Kretschmer, Pavlov, and Sheldon. The impact of current developments in neuropsychology and in cognitive psychology is discussed.
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8040483
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Culture, personality, and psychopathology.
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Culture needs to be made more central to the understanding of personality and psychopathology. New anthropological views describe cultural influences on personality and psychopathology by focusing on the effect of social change in local contexts on sociosomatic and sociopsychological processes. This view discloses the cultural biases built into dominant North American professional models of diagnosis and contrasts with past uses of culture in cross-cultural research. Examples from Chinese and Puerto Rican societies illustrate how indigenous interpersonal models of personality and psychopathology that focus on social processes can augment the cross-cultural validity of clinical formulations.
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8040482
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Categorical distinctions in the study of personality disorder: implications for classification.
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This article discusses the historical underpinnings of psychiatric classification and examines empirical evidence relevant to (a) whether personality disorders are distinct from each other and from normal personality and (b) whether personality disorders should be classified separately from other mental disorders. At the phenotypic level, research evidence strongly supports the use of a dimensional model to delineate personality disorders; evidence about their genotypic representation is less conclusive though still supportive. Neither empirical nor rational arguments indicate strong justification for separating personality disorders from other mental disorders, as has been done in both the third and fourth editions of the Diagnostic and Statistical Manual of Mental Disorders. Distinctions between abnormal and disordered personality are considered, and suggestions are made for more satisfactory diagnostic classificatory schemes.
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8040481
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Temperament and the development of personality.
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We present a psychobiological approach to personality development, incorporating developmental principles outlined by R. B. Cairns (1979). We review individual differences in temperament and ask how a temperamental approach to personality might be congruent with these complex and flexible principles. We then illustrate the nature of temperamental processes by considering several developmental topics. We first consider the interaction of infant distress-proneness and maternal behavior in the development of attachment. We then describe the development of self-regulatory mechanisms, emphasizing development of conscience, aggression, and mastery motivation. Finally, we briefly review mechanisms of temperament and environment interaction, illustrating these processes through variable developmental pathways for risk of adolescent and adult psychopathology. Throughout, we stress the idea that temperamental models of personality development are dynamic, interactive, and fit well with Cairns's developmental principles.
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8040480
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Cyclical processes in personality and psychopathology.
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Both the understanding of psychopathology and the ability to intervene therapeutically are enhanced by an appreciation of the central role of vicious circles in the development and maintenance of psychological disorder. It is usually possible to discern a structure to people's difficulties in which internal states and external events continually re-create the conditions for the re-occurrence of each other in all too real psychological version of the mythical perpetual motion machine. The present article illustrates how such circular processes work in a number of representative types of psychological difficulty and discusses the implications of this conception for understanding psychopathology and for therapeutic intervention.
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8040479
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Ego mechanisms of defense and personality psychopathology.
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It is often not just life stress but also a person's idiosyncratic response to life stress that leads to psychopathology. Thus, despite problems in reliability, the validity of defenses makes them a valuable diagnostic axis for understanding psychopathology. By including a patient's defensive style as part of the diagnostic formulation, the clinician is better able to comprehend what seems initially most unreasonable about the patient and to appreciate what is adaptive as well as maladaptive about the patient's defensive distortions of inner and outer reality. Clinical appreciation of the immature defenses (e.g., hypochondriasis, fantasy, dissociation, acting out, projection, and passive aggression) is particularly useful in classifying and caring for individuals with personality disorders.
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8040478
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Personality and psychopathology: genetic perspectives.
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Genetic factors exert an important influence on adult personality traits, accounting for anywhere between 30% and 60% of the variance. Heredity is also important for most forms of psychopathology and plays a major role in several theories that relate personality to psychopathology. Despite this, there has been surprisingly little multivariate genetic research reported on joint analyses of personality and psychopathology. The small amount of available data suggests that genes may account for over 50% of the observed correlation between neuroticism and state symptoms of anxiety and depression. The mechanisms behind such strong genetic correlations are crucial for understanding the causal relationship between a personality trait and a disorder because genetically influenced biological systems may operate as exogenous "third-party" factors that are responsible for what appear to be phenotypic cause-effect relationships. We illustrate how recent analytical advances in behavior genetics can use multivariate family data to address questions about the causal role of personality in psychopathology.
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8040477
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Structures of personality and their relevance to psychopathology.
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Trait concepts are used extensively in psychopathology research, but much of this research has failed to consider recent advances in the dimensional structure of personality. Many investigators have discounted the importance of this structural research, arguing that (a) little progress has been made in this area, (b) structural models have little direct relevance for psychopathology research, and (c) the principal methodological tool of structural research--factor analysis--is too subjective to yield psychologically meaningful results. We dispute each of these objections. Specifically, we offer an integrative hierarchical model--composed of four higher order traits--that is congruent with each of the major structural subtraditions within personality. We also discuss the implications of this integrative scheme for basic trait research, for the conceptualization and assessment of psychopathology, and for the etiology of disorder.
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8040476
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Schizophrenia and personality: exploring the boundaries and connections between vulnerability and outcome.
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This article discusses the issues and evidence concerning the relationship between schizophrenia and personality. We examine personality dimensions in individuals with schizophrenia, both before and after the onset of their psychoses, and in their relatives. Schizophrenia is associated with high levels of peculiarity and neuroticism and with low levels of extraversion. The relationships between schizophrenia and both psychopathy and creativity remain unclear. Personality dimensions vary in the manner in which they are associated with a variety of correlates of psychopathology, such as prognosis. We recommend that psychopathologists interested in schizophrenia devote more attention to the study of personality.
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8040475
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Personality variables and disorders in anorexia nervosa and bulimia nervosa.
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All dominant models of the eating disorders implicate personality variables in the emergence of weight concerns and the development of specific symptoms such as bingeing and purging. Standardized measures of personality traits and disorders generally confirm clinical descriptions of restricting anorexics as constricted, conforming, and obsessional individuals. A less consistent picture suggesting affective instability and impulsivity has emerged from the assessment of subjects with bulimia nervosa. Considerable heterogeneity exists within eating disorder subtypes, however, and a number of special problems complicate the interpretation of personality data in this population. These include young age at onset, the influence of state variables such as depression and starvation sequelae, denial and distortion in self-report, the instability of subtype diagnoses, and the persistence of residual problems following symptom control.
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8040474
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Somatoform disorders: personality and the social matrix of somatic distress.
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Personality traits that may contribute to somatization are reviewed. Negative affectivity is associated with high levels of both somatic and emotional distress. Agreeableness and conscientiousness may influence interactions with health care providers that lead to the failure of medical reassurance to reduce distress. Absorption may make individuals more liable to focus attention on symptoms and more vulnerable to suggestions that induce illness anxiety. More proximate influences on the selective amplification of somatic symptoms include repressive style, somatic attributional style, and alexithymia; however, data in support of these factors are scant. Most research on somatoform disorders confounds mechanisms of symptom production with factors that influence help seeking. Longitudinal community studies are needed to explore the interactions of personality with illness experience and the stigmatization of medically unexplained symptoms.
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8040473
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Dissociative tendencies and dissociative disorders.
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Although dissociative disorders are relatively rare, dissociative experiences are rather common in everyday life. Dissociative tendencies appear to be modestly related to other dimensions of personality, such as hypnotizability, absorption, fantasy proneness, and some facets of openness to experience. These dispositional variables may constitute diathesis, or risk factors, for dissociative psychopathology, but more complex models relating personality to psychopathology may be more appropriate. The dissociative disorders raise fundamental questions about the nature of self and identity and the role of consciousness and autobiographical memory in the continuity of personality.
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8040472
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Temperament, personality, and the mood and anxiety disorders.
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Literature on temperament, personality, and mood and anxiety disorders is reviewed. The review is organized primarily around L. A. Clark and D. Watson's (1991b) tripartite model for these disorders, but other influential approaches are also examined. Negative affectivity (or neuroticism) appears to be a vulnerability factor for the development of anxiety and depression, indicates poor prognosis, and is itself affected by the experience of disorder. Positive affectivity (or extraversion) is related more specifically to depression, may be a risk factor for its development, suggests poor prognosis, and also may be affected by the experience of disorder. Other personality dimensions (e.g., anxiety sensitivity, attributional style, sociotropy or dependence, autonomy or self-criticism, and constraint) may constitute specific vulnerability factors for particular disorders. More longitudinal and measurement-based research that jointly examines anxiety and depression is needed.
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8040469
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Malignant proliferating onycholemmal cyst.
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A slowly growing malignant tumor of the nail unit in a 74-year-old female is reported. At light microscopy, the tumor was composed of small keratinous cysts with abrupt central keratinization, and of solid nests and strands of atypical keratinocytes filling the dermis and penetrating the phalangeal bone. In our view, this can be regarded as the malignant analog of the keratin cysts arising from the nail bed epithelium, as first reported by Samman in 1959. Since, according to several authors, the nail bed epithelium is comparable to the outer root sheath of the follicle and since the reported tumor showed some analogies with malignant proliferative trichilemmal cyst, it is suggested that this new entity be designated as malignant proliferating onycholemmal cyst.
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8040468
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Necrobiosis in solitary mastocytoma: coincidence or pathogenesis?
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The coexistence of solitary mastocytoma and necrobiotic changes resembling granuloma annulare in the same lesion has not been reported to our knowledge. A 3 1/2-year-old child with a plaque on the arm clinically and histologically consistent with solitary mastocytoma showed characteristic necrobiotic foci indistinguishable from granuloma annulare. We speculate that mast cell degranulation may be involved in the pathogenesis of necrobiosis by altering fibroblast enzyme activity and/or producing prolonged inflammatory reactions.
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8040467
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Hamartoma of the tongue in an infant with a primary diagnosis of ectrodactyly-ectodermal dysplasia-cleft lip and palate syndrome.
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We describe a case of an unusual tongue hamartoma associated with ectrodactyly-ectodermal dysplasia-clefting syndrome in a 3-month-old white female infant. The lesion was composed of a mixture of salivary glands, adipose tissue, smooth muscle and skeletal muscle in a haphazard fashion. Lingual hamartomas are rare and can present a clinical differential diagnostic problem. We review the literature on this unique combination of malformations.
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8040466
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Giant folliculosebaceous cystic hamartoma.
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We report a case of a giant cystic cutaneous adnexal hamartoma which showed fibrofollicular units embedded in the stroma with aberrant fat tissue. There were many sebaceous lobules in the fibrofollicular units, and its histologic features were consistent with conventional folliculosebaceous cystic hamartoma. Given the unique clinical history and appearance, this lesion is considered to be a congenital variant.
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8040465
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Atypical melanocytic lesions in epidermolysis bullosa.
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We report a 6-year-old female with recessive dystrophic epidermolysis bullosa (RDEB) who presented with a very large acquired melanocytic lesion. The lesion demonstrated many features both clinically and histologically that made the distinction from malignant melanoma difficult. The pathogenesis of this lesion and other unusual melanocytic lesions seen in the setting of acute and chronic blistering disorders seems related to repeated episodes of disruption of the dermal-epidermal junction.
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8040464
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Adenocarcinoma of the mammary-like glands of the vulva: a concept unifying sweat gland carcinoma of the vulva, carcinoma of supernumerary mammary glands and extramammary Paget's disease.
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An unusual case of primary adenocarcinoma of the vulva is described. It combined features of the three different types of adenocarcinoma of the skin of the vulva which are currently recognized, i.e. sweat gland carcinoma, adenocarcinoma derived from supernumerary mammary glands, and extramammary Paget's disease (EMPD). Central in this tumor was a recently recognized type of cutaneous gland which appeared special for the anogenital region and was distinguished because it combined morphological features of eccrine, apocrine and mammary glands. As it most resembles mammary glands, it is named "mammary-like gland". On the basis of the case presented and of a critical review of the literature, it was concluded that, with the exception of a few sweat gland carcinomas similar to those elsewhere in the skin, adenocarcinomas of the skin of the vulva form a single category of neoplasms with a variable expression of features reminiscent of eccrine, apocrine and mammary gland carcinomas. The data strongly suggested a common derivation from the mammary-like gland or, in cases of EMPD, its related germinative cells in the epidermis.
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8040463
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Mycosis fungoides skin lesions contain CD8+ tumor-infiltrating lymphocytes expressing an activated, MHC-restricted cytotoxic T-lymphocyte phenotype.
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In prior studies, we showed that most CD8+ cells infiltrating skin lesions of CD3+CD4+ mycosis fungoides were CD3+ T-lineage tumor-infiltrating lymphocytes (TIL) whose overall phenotype was suggestive of MHC-restricted cytotoxic T lymphocytes (CTL). However, their lack of cytotoxic-associated granzyme A mRNA suggested that they might be unactivated CTL precursors. In this study, we used single- and double-label immunohistologic techniques to assess the expression of TIA-1-reactive protein and HLA-DR by these CD8+TIL. Monoclonal antibody TIA-1 recognizes a novel family of proteins expressed preferentially by cytotoxic cells, including some that lack granzyme A. HLA-DR is a marker of T-cell activation. Single-label studies of 32 cases showed that CD8+TIL and TIA-1+ cells constituted a variable minority of the total cellular infiltrate and had a similar distribution. Double-label studies of 14 cases showed that in most instances the aggregate phenotype of the majority of CD8+TIL was CD3+TIA-1+HLA-DR+CD56-CD57-. These findings suggest that many of the CD8+TIL within skin lesions of CD3+CD4+ mycosis fungoides are activated, MHC-restricted CTL.
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8040461
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Immunofluorescent analysis of the basement membrane zone in lichen planus suggests destruction of the lamina lucida in bullous lesions.
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Lichen planus is an inflammatory dermatosis which is characterized histologically by an intense lymphocytic infiltrate at the dermal epidermal junction. This frequently results in disruption of the basement membrane zone, occasionally causing clinical blisters. In order to better understand the specific portion of the basement membrane zone which is disrupted by the lymphocytic infiltrate, we examined 7 cases of lichen planus with antibodies directed against anchoring filaments (GB3), the bullous pemphigoid antigen, anchoring fibrils (type VII collagen) and type IV collagen. In lesions without separation at the BMZ, all antibodies were strongly expressed, as in normal skin. In lesions with early separation, there was a focal decrease in GB3 staining, but types VII and IV collagen labelled normally. In lesions resulting in blisters, GB3 staining was essentially absent, and anti-types IV and VII collagen remained, but stained in a disrupted, less discrete pattern. The bullous pemphigoid antigen showed only slight deviation from the normal staining pattern. These findings suggest that the basement membrane zone in lichen planus is disrupted in the lamina lucida region. The lamina densa and sub-lamina densa zones remain intact even in bullous lesions of lichen planus.
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8040462
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Granuloma annulare: an immunohistochemical study.
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The monocyte/histiocytic response in granuloma annulare has not been extensively studied. We studied the immunohistochemical staining pattern in granuloma annulare by using a panel of markers for "histiocytic" cells including Ham 56, KP1, factor XIIIa, Mac 387, vimentin, and lysozyme. The infiltrate failed to stain with the histiocytic markers, except with antibodies against vimentin and lysozyme. Commonly used histiocytic markers for infectious, immunogenic, and foreign body granulomas fail to stain the infiltrate in granuloma annulare. We hypothesize that a locally derived, immunologically distinct population of histiocytes produces the reaction pattern of granuloma annulare.
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8040460
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Subcutaneous T-cell lymphoma: a clinical, histopathologic, and immunohistochemical study of six cases.
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Recently, T-cell lymphoma localized to the subcutaneous tissue has been reported. We report the clinical, histologic, immunohistochemical, and molecular genetic findings in 6 patients who we believe had this peculiar T-cell lymphoma with its unique morphologic and clinical features. All patients presented with deep-seated nodules, most frequently on the extremities, and with systemic complaints of low-grade fever, fatigue, myalgias, and weight loss. In all cases, the neoplastic lymphocytic infiltrate was confined to the subcutaneous tissue, predominantly in a lobular pattern. Hemorrhage, necrosis, and rare erythrophagocytosis were also seen. Immunohistochemical staining was predominantly T-cell reactive (CD43, CD3, and CD45RO). Clonal rearrangements of the beta and gamma chains of the T-cell antigen receptor genes were found in 1 case. Three of the 6 patients died within 22 months of the diagnosis of lymphoma. We believe that subcutaneous T-cell lymphomas are a distinctive group of peripheral T-cell lymphomas with unusual clinical and morphologic features and that they should be distinguished from other types of lymphoma.
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8040459
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The super PET 3000-E: a PET scanner designed for high count rate cardiac applications.
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Mathematical models for the delineation of regional myocardial perfusion and metabolism with PET require faithful reconstruction of arterial and myocardial time-activity curves following administration of radiotracers. High temporal resolution is often required in such measurements. Many commercially available tomographs exhibit long dead times that limit their count rate capabilities. To overcome these limitations, we developed and tested a whole-body tomographic device (Super PET 3000-E) with high count rate capabilities. The use of cesium fluoride scintillation detectors coupled with a one-to-one detector photomultiplier configuration reduces the system resolving and dead times. The Super PET 3000-E was subjected to a series of tests with phantoms to determine its resolution, sensitivity, linearity, count rate capabilities, dead time, and random coincidence contribution. The system sensitivity is 136 kcounts/s/microCi/ml and its transverse and longitudinal resolutions are 8.5 and 10.5 mm full width at half-maximum, respectively. The system can easily record a total event rate of 2.0 Mcounts/s with minimal dead time loss and excellent linearity. The system fulfills its design goals and allows the very high count rate performance needed for the application of the physiological models used in our cardiac studies.
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8040458
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Simultaneous detection of multiple components of motion with MRI.
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Simultaneous detection of two or more components of motion using new magnetic resonance pulse sequences was investigated. The technique employs Fourier phase encoding to encode the first component, and phase contrast detection to encode the second. Although the technique can be generalized to any number of spatial dimensions and motional orders, applications in which one or two spatial dimensions are obtained with a single Fourier velocity or acceleration dimension are most likely to be useful. For example, Fourier-encoded velocity and phase-contrasted acceleration information can be combined into the same image. Several variations of the pulse sequence were investigated in phantoms and human volunteers. The first variation acquired images having an appearance similar to that of Fourier velocity-encoded images in which signal displacement is proportional to velocity, but with pixel intensity determined by acceleration. In another variation two spatial dimensions were acquired with a third dimension that uses Fourier velocity encoding to measure axial velocity within a curved tube. Radial velocity components were determined simultaneously with a second velocity-encoding gradient pulse. The phantom and in vivo results presented here suggest that simultaneous detection of two or more components of motion is feasible.
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8040453
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Adult-onset disseminated tracheobronchial papillomatosis: CT features.
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The high resolution CT (HRCT) findings in an adult with disseminated tracheobronchial papillomatosis are discussed. In addition to polypoid masses within the trachea and main bronchi, diffuse ill-defined parenchymal centrilobular opacities were present; these reflect lesions within the small airways. Some of the nodules showed central cavitation. In a patient with centrilobular opacities, some of which cavitate, on HRCT and concomitant endobronchial or endotracheal abnormality, disseminated papillomatosis should be considered in the differential diagnosis, particularly if there is a history of hoarseness or laryngeal disease.
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8040451
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Gd-DTPA: an alternative contrast medium for CT.
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The purpose of this study was to demonstrate that gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) could be used as a contrast medium in CT as an alternative to iodine-based compounds. Solutions of different concentrations of Gd-DTPA and iopromide were scanned in a tissue equivalent phantom and it was shown that Gd-DTPA caused 2.5 times the attenuation of an equimolar solution of iopromide. From these in vitro studies an in vivo dose of 0.5 mmol/kg Gd-DTPA was calculated to be equivalent to 50 ml iopromide 300. Pre- and postenhancement CT was performed in a volunteer using Gd-DTPA intravenously, and adequate enhancement occurred in intracranial vessels. Gd-DTPA can be used to provide enhancement during CT and might be of value in iodine-sensitive patients.
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8040452
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Pachygyria in a neonate with prenatal cocaine exposure: MR features.
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Clinical and MR findings of a neonate with diffuse severe pachygyria and prenatal exposure to cocaine are presented. The teratogenicity of cocaine is reviewed.
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8040450
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Calculation of cross-sectional geometry of bone from CT images with application in postmenopausal women.
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The objectives of this study were to develop a software program that calculates bone cross-sectional area (CSA) and moments of inertia from digital images, test the computations for accuracy, and implement the software in a study of longitudinal changes in bone properties in a large group of postmenopausal women. A program called SLICE was adapted to use computed tomography (CT) bone images as input. The main outcome variables of the resulting program, SLICE_CT, were bone CSA, areal moments of inertia, and mass-weighted moments of inertia. SLICE_CT was tested for accuracy using representative arrays of CT numbers that approximate cross-sections of cortical bone. Then the technique was applied to images from a 3 year longitudinal study of the radius in 86 postmenopausal women who underwent quantitative CT of the dominant radius at 30% the distance from the wrist to the elbow. The mean age of the subjects at entry into the study was 57 years. Images at baseline and at 3 years were analyzed, and the null hypothesis of no change in cross-sectional geometry was tested by a paired difference two-tailed t test. The error of SLICE_CT was < 1% with proper segmentation, using half-maximal height as the threshold. In the longitudinal study of postmenopausal women, the mean change of CSA of the radius was -1.4% (SD = 3.0%; p < 0.001). However, there was a compensatory 2.4% increase in the cross-sectional second polar moment of inertia (SD = 3.7%; p < 0.001). SLICE_CT is an accurate method with which to determine cross-sectional geometry of digital images and can be used to detect changes in cross-sectional geometry of the radius with age in postmenopausal women. The results indicate that the radius remodels to compensate for bone loss and decreasing material properties of bone associated with aging.
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8040449
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CT in adnexal torsion with emphasis on tubal findings: correlation with US.
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Our goal was to determine the CT and US aspects of the fallopian tube in adnexal torsion. The CT scans and US studies of 10 patients with surgically proven unilateral torsion of the adnexa were reviewed. On CT the fallopian tube on the involved side was identified in eight cases as an almost tubular or comma-shaped structure extending from the uterine cornua and covering partially the adnexal mass. This tube was significantly thickened and measured 20-40 mm. Hemorrhage (density > or = 50 HU on precontrast CT scans) was present in the tube in six patients. A heterogeneous contrast agent uptake was detected in the tube in five patients. An adnexal mass was visualized on the involved side in all patients, with hemorrhage in the mass in four patients. Peritoneal fluid and/or ileus were present in six patients. On US an echogenic structure that corresponded to the enlarged tube visualized on CT was detected in three cases and an adnexal mass in all cases. Thickening of the fallopian tube with hemorrhage could be detected by CT and is suggestive of torsion especially if associated with an adnexal mass.
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8040448
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MR evaluation of clinically suspected adnexal masses.
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Our goal was to determine the sensitivity, specificity, predictive value, and accuracy of pelvic MRI in the prospective evaluation of women with a clinically suspected pelvic mass. One-hundred three patients with clinically suspected pelvic masses were prospectively evaluated by pelvic MRI. Masses were analyzed for size, location, morphological characteristics, and signal behavior. Masses were classified as benign, malignant, or indeterminate and in every case an attempt was made to generate a specific diagnosis according to previously reported characteristic MR appearances. Surgical follow-up was obtained within 3 months of MRI examination for all patients, excepting 11 patients with typically appearing leiomyomas. One hundred twenty pelvic masses were confirmed. Magnetic resonance was 100% sensitive and 99% specific in prospectively diagnosing dermoids, 96% sensitive and 100% specific in diagnosing subserosal leiomyomas, and 92% sensitive and 91% specific in diagnosing endometriomas. When physical examination or ultrasound examination is inconclusive, pelvic MRI can aid in the evaluation of women with a suspected pelvic mass. By identifying these common benign gynecologic conditions, unnecessary surgery can be avoided.
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8040447
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Evaluation of RARE-MR urography in the assessment of ureterohydronephrosis.
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The goal of this prospective study was to evaluate the value of the fast imaging sequence called RARE-MR urography (RMU) for the diagnosis of ureterohydronephrosis. Sixty-nine patients underwent this procedure. The results were compared with those obtained by intravenous urography (IVU) and ultrasonography (US). The accuracy of RMU in the detection of urinary tract dilatation and the localization of the level of obstruction was excellent (100%). The determination of the type of obstruction, intrinsic versus extrinsic, was 80% by IVU and 60% for RMU. The RMU sequence alone could not specify the nature of the obstruction. Functional information about the obstructed collecting system could not be obtained. The RMU technique may be considered in the following circumstances: contraindications to IVU (allergy to contrast medium, severe renal failure), impairment of renal excretion, and failure to locate the level of obstruction by US. The absence of ionizing radiations favors the promotion of this procedure to study ureterohydronephrosis during pregnancy.
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8040446
|
MR angiography of renal vascular malformations.
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We wanted to determine whether three-dimensional phase contrast (3DPC) MR angiography is clinically useful in the diagnosis of renal vascular malformations. Three-dimensional PC MR angiography was performed in 22 patients with gross hematuria and in 8 healthy volunteers. Small flip angles and 60 cm/s velocity encoding best demonstrated the normal intrarenal arteries with arteriovenous differentiation in the eight healthy volunteers. In the 22 patients with gross hematuria, intraarterial digital subtraction angiography demonstrated cirsoid-type malformations in 6 patients, aneurysmal-type malformations in 3 patients, and normal vascular anatomy in 13 patients. Magnetic resonance angiography detected all three aneurysmal-type malformations and four of the cirsoid-type malformations. Small cirsoid-type malformations were not detected in two patients. The moderate or large malformations were demonstrated as dilated and tortuous feeding arteries and high intensity renal veins with high flow velocity. We found no correlation between signal intensity in the suprarenal inferior vena cava and the presence of arteriovenous shunts. There were no false-positive cases. Sensitivity, specificity, and accuracy in this series were 78, 100, and 91%, respectively.
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8040445
|
Effects of meal intake on the flow velocity in the superior mesenteric artery: evaluation with 2D phase mapping MRI.
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Reliable results in MR flow measurements have been reported in humans. The current study was performed to evaluate the effects of a meal intake on the flow velocities in the superior mesenteric artery (SMA) and aorta by using 2D phase-mapping MRI. A constant flow phantom generating 0-150 cm/s of flow velocities was constructed to evaluate the accuracy of MR flow measurements. Eleven healthy volunteers underwent serial MRI once before and three times after a mixed meal intake (700 kcal). Reliable MR flow measurements were validated in the constant flow phantom. In the healthy volunteers, the SMA and aorta had triphasic flow velocity waveforms in one cardiac cycle. Ingestion of a mixed meal increased flow velocities in the SMA. Peak velocities were observed at 20 min after the meal. The aortic flow velocities were unaffected by the meal. A 2D phase-mapping MR technique is feasible to evaluate the SMA and aortic flow velocities. Evaluation of the flow velocities in the SMA may contribute to understanding intestinal as well as hepatic conditions in humans.
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8040444
|
Improved detection of small insulinomas with intravenous dynamic CT.
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To evaluate the usefulness of intravenous dynamic CT in demonstrating angiographically negative insulinomas. Two patients with endocrinologic evidence of insulinoma were examined with intravenous bolus-dynamic CT. Angiographically negative insulinomas as small as 5-7 mm were demonstrated unequivocally as enhancing nodules. Intravenous dynamic CT using larger amounts of contrast material can improve detection of small (< 1.0 cm) insulinomas.
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8040443
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Detection of focal hepatic masses: STIR MR vs. CT during arterial portography.
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Our goal was to compare short tau inversion recovery MRI (STIR) to CT during arterial portography (CTAP) in the detection of hepatic lesions. Over a 24 month period, 40 patients evaluated for possible hepatic resection underwent T1, T2, and STIR MRI and CTAP. These studies were randomly ordered and interpreted by two independent readers. The total number of lesions and number of lesions within each hepatic segment were analyzed using McNemar's test. Readers 1 and 2 detected 95 and 91 lesions by CTAP and 78 and 83 by STIR, respectively, which was not significantly different (p = 0.1, reader 1; p = 0.4, reader 2). For both readers CTAP and STIR MRI detected more lesions than either T2 or T1 MRI (p < 0.01). In the medial segment, readers 1 and 2 detected 18 and 17 lesions by CTAP and 7 and 9 by STIR, respectively (p = 0.01, reader 1; p = 0.035, reader 2). Short tau inversion recovery MRI and CTAP are similar in total lesion detection except in the medial segment where lesions were more frequently identified by CTAP than STIR MRI.
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8040441
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Cine MRI of mitral regurgitation in planes angled along the intrinsic cardiac axes.
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This prospective study was designed to evaluate the mechanism and severity of mitral regurgitation (MRG) by means of cine MRI using planes angled along the intrinsic cardiac axes. In 25 patients with MRG, analysis of the direction, extent, and distribution of left atrial signal void area was performed on both two chamber and four chamber cine MRI views. Cine MRI features including qualitative grading, maximal length of regurgitant jet, and ratio of regurgitant jet area to left atrial area were compared with the results of color flow Doppler (CFD) mapping (n = 25), angiography (n = 20), and regurgitant fraction as determined at catheterization (n = 15). In the four chamber view, cine MRI demonstrated central extension of regurgitant jet (n = 8) in cases with dilatation of valve annulus or retraction of both mitral valve leaflets, anterior extension (n = 8) in cases with prolapse of the posterior leaflet, and posterior extension (n = 7) in cases with prolapse of the anterior leaflet or retraction of the posterior leaflet. In two cases of mild MRG with small signal void area, evaluation of mechanism was not feasible. The results of cine MRI and angiographic qualitative gradings were the same in 19 of the 20 patients and differed by one grade in the other patient. In the 25 patients, maximal length of the regurgitant jet was well correlated with both regurgitant jet area and ratio of the jet area to the left atrial area as determined by CFD mapping (r = 0.91, r = 0.85, p < 0.0001, respectively). In 15 patients the maximal length of regurgitant jet was correctly correlated with regurgitant fraction determined at catheterization (r = 0.76, p < 0.001). Cine MRI by means of planes angled along the intrinsic cardiac axes allows assessment of both the mechanism and the severity of MRG.
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8040442
|
High resolution cine MRI of vessel distension.
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We have evaluated the ability of high resolution cine MRI to quantify vessel distension. Gradient echo imaging was used to acquire high resolution, cardiac-triggered imaging of the ascending aorta in normal volunteers to measure changes in the cross-sectional area of the lumen over the cardiac cycle. The effects of temporal resolution, spatial resolution, and the radiofrequency flip angle on the measurements were investigated. High spatial resolution improved the ability to detect changes in the luminal area. High temporal resolution allowed better tracking of maximal vessel distension. A small flip angle reduced the saturation of slow flow observed in imaging acquired using a large flip angle. Our study has demonstrated that high spatial resolution and high temporal resolution can substantially improve the measurement of vessel distension. We have overcome problems of intravoxel dephasing and spin saturation by using high spatial resolution, a short echo time with flow compensation, and a small flip angle.
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8040440
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Postmediastinoscopy changes in chest CT.
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To know the CT changes that may be seen in the mediastinum after uncomplicated mediastinoscopy. Noncontrast CT was performed on 10 patients on the 1st, 3rd, and 5th days after the procedure. We encountered linear and diffuse increased attenuation within the mediastinum as well as air bubbles. By the 5th day postmediastinoscopic changes resolved. We never found air-fluid levels, fluid collections, or other abnormalities. Expected postmediastinoscopic changes are not to be confused with potential postprocedure complications such as hemorrhage or infection.
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8040439
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CT of pulmonary epithelioid hemangioendothelioma.
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To describe the radiological findings of long-standing pulmonary epithelioid hemangioendothelioma. Serial radiography and CT, including high-resolution CT scans, were performed in two patients. The tumor has remained radiographically stationary for 10 and 20 years, respectively. On CT, both patients showed multiple calcified pulmonary nodules, up to 1 cm in size with a perivascular distribution. Interstitial involvement was seen in one case. Calcification and perivascular location of the tumoral nodules were characteristic CT findings in our cases.
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8040438
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CT appearance of endobronchial non-Hodgkin lymphoma.
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Endobronchial involvement by non-Hodgkin lymphoma (NHL) is a very rare manifestation of the disease. We describe this unusual entity and emphasize the role of chest CT scan. Two radiologists reviewed the chest radiographs and CT scans of two patients with endobronchial NHL. The studies were reviewed for the presence and extent of endobronchial involvement. Bronchoscopic confirmation was obtained. In each case CT showed endobronchial lesions that correlated well with the extent of tumor found at bronchoscopy. Computed tomography is useful to suggest endobronchial NHL in the proper clinical context and to assist the bronchoscopist in selecting the appropriate site for biopsy.
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8040437
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Bronchiolitis obliterans associated with rheumatoid arthritis: findings on HRCT and dynamic expiratory CT.
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To show the CT findings of bronchiolitis obliterans (BO) associated with rheumatoid arthritis. We used high-resolution CT (HRCT) and dynamic expiratory cine CT to evaluate two patients with rheumatoid arthritis and a clinical diagnosis of BO. Both had pulmonary function tests to correlate with the radiographic findings. High-resolution CT showed bronchiectasis and mosaic perfusion in both patients. Expiratory CT showed multiple scattered areas of air trapping consistent with small airway obstruction. Imaging findings correlated with pulmonary function tests, which showed severe airway obstruction and inhomogeneous lung ventilation. Pulmonary HRCT and dynamic expiratory CT are useful in verifying the clinical diagnosis of BO in patients with rheumatoid arthritis, particularly those too unstable to undergo open lung biopsy.
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8040436
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Spiral CT evaluation of the trachea and bronchi.
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We report two cases in which spiral CT with three-dimensional (3D) reconstruction was used to evaluate abnormalities of the trachea and bronchi. Two patients with known airway abnormalities, one with a carinal tumor and the other with a postoperative bronchial stenosis, had spiral CT of the chest performed. Images were reconstructed in the coronal plane as well as using a curved planar reformat and shaded surface display. Spiral CT with 3D reconstruction provided excellent anatomic definition of the central airway abnormalities. In our two cases the information provided was used in both the clinical assessment and treatment planning of the patients. Spiral CT was useful in the evaluation of two patients with central airway abnormalities. Further investigation into applications of spiral CT for the evaluation of the central airways appears warranted.
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8040435
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MRI of subperiosteal hematoma of the orbit.
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The MR findings of two cases of subperiosteal hematoma of the orbit are described. We present two cases of subperiosteal hematoma of the orbit following minor head trauma, the first presenting with chronic progressive exophthalmos and the second with acute proptosis. Both cases showed a well-defined biconvex mass with a curvilinear hypointense band in the superior portion of the orbit. In Case 1 chronic hematoma demonstrated high signal on both T1- and T2-weighted imaging, and in Case 2 acute hematoma displayed intermediate signal on T1-weighted imaging and high signal on T2-weighted imaging. Follow-up MRI in Case 2 demonstrated the typical signal changes from acute to subacute hematoma. Subperiosteal hematoma has a characteristic appearance on MRI which is virtually diagnostic. In proper clinical settings MRI is the modality of choice for the detection and characterization of this hematoma.
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8040434
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SPECT with HMPAO compared to PET with FDG in Huntington disease.
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It is the aim of this study to compare the performance of 99mTc-d,l-hexamethylpropyleneamine oxime (HMPAO) SPECT with that of [18F]fluorodeoxyglucose (FDG) PET in detecting striatal dysfunction as it occurs in Huntington disease (HD). For the determination of regional cerebral glucose consumption, the PET camera PC-4096 was used; the cerebral uptake of HMPAO was measured using the three-head SPECT camera TRIAD. Eight patients with manifest HD, seven subjects at risk for HD, and nine normal individuals were included in the study. In both modalities data evaluation was performed using caudate-to-whole-slice (C/S) ratios. The patients' data were compared to 95% confidence intervals determined in the nine controls. The PET and SPECT C/S values correlated significantly (n = 24; r = 0.87; p < 0.0001). The C/S values were significantly reduced in PET in all eight and in SPECT in seven of the eight HD patients studied. Five of the seven at-risk subjects had normal C/S values in PET and SPECT, one showed reduced C/S values in both diagnostic methods, and the remaining at-risk individual showed a reduced C/S value in PET only. Thus, concordant results between PET and SPECT were obtained in seven of eight patients and six of seven at-risk subjects studied, corresponding to an 87% accuracy of SPECT in the detection of striatal dysfunction as compared to the "gold standard" PET. With use of a multidetector camera, HMPAO-SPECT comes near the performance of FDG-PET in the diagnosis of striatal dysfunction as it occurs in HD.
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8040433
|
MR angiography of peripheral posterior inferior cerebellar artery aneurysms.
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A small subset of posterior inferior cerebellar artery (PICA) aneurysms arise distal to the vertebral artery origin of the PICA. We present two such cases seen on conventional angiography and MR angiography (MRA). The findings in two patients are presented. In one the aneurysm presented with subarachnoid hemorrhage. The second was found incidentally but later ruptured. There was good agreement between the appearance of the aneurysms on MRA and conventional angiography. Awareness of the possibility of peripheral PICA aneurysms and their features is important. The positioning of the volume of excitation for MRA may have to be adjusted to include a very low PICA caudal loop.
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8040432
|
MRI of carotid angiopathy after therapeutic radiation.
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Our goal was to assess whether significant secondary atherosclerotic changes from radiation can be detected on SE MR of the neck. Pre- and postradiation MR scans of 16 patients with head and neck malignancies were studied randomly, independently, and blindly by two readers to determine the frequency of narrowing of the carotid arterial lumen and obliteration of the carotid space within the carotid sheath. Interval narrowing of either the common, internal, or external carotid artery lumen was seen in 108 of 192 (56%) of vessels evaluated on postradiation MR scans compared with preradiation studies. The differences in the grades of vessel luminal diameter were statistically significant (p < 0.05 for one reader and p < 0.0001 for the other reader). Among the 16 patients, 3 patients had vessels with a critical degree of stenosis, newly appearing on postradiation scans. Seven of 16 patients had diffuse obliteration of the planes within the carotid space. The incidence of accelerated atherosclerosis from therapeutic radiation may be greater than expected in nonirradiated patients. Magnetic resonance scans are an effective, noninvasive method for this type of follow-up.
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8040431
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MRI-guided laser-induced interstitial thermotherapy of cerebral neoplasms.
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Laser-induced interstitial thermotherapy (LITT) using a neodymium:yttrium aluminum garnet (Nd: YAG) laser is a new therapeutic approach in the treatment of brain tumors. The purpose of our study was to determine the value of MRI in monitoring LITT. Eight patients with intracerebral tumors were treated with LITT. The light guide was inserted via an applicator sheath that was implanted stereotaxically with CT guidance. The laser irradiation was performed within the MR unit and monitored by repetitive measurements of a T1-weighted 2D-FLASH sequence. During therapy in all patients, typical changes of signal intensity were seen. A gradually increasing central zone of high signal intensity was surrounded by an increasing peripheral area of reduced signal intensity. The diameter of an enhancing rim at the outer border of the peripheral area after Gd-DTPA was considered as the total lesion size. The lesion size as determined on 2D-FLASH scans during LITT accounted for 88-100% (mean 93.5%) of total lesion size on T1-weighted images after Gd-DTPA acquired immediately after therapy. On T2-weighted images the signal intensities of the two zones were vice versa. Follow-up studies showed a decrease of total lesion size (15-87%). Our results demonstrate that MRI is feasible and effective in monitoring LITT. However, the role of LITT in the therapeutic workup of brain tumors still has to be defined in future clinical studies.
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8040430
|
Quantitative MR analysis of glucocorticoid effects on peritumoral edema associated with intracranial meningiomas and metastases.
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The purpose of our study was to quantify peritumoral brain edema (PTE) in vivo using NMR relaxation time imaging, as the longitudinal relaxation time T1 is proportional to tissue water content, and to use the method for monitoring the effects of glucocorticoids (GCCs) on PTE in brain tumor patients as a function of time. Relaxation time imaging (T1 maps) was done on a 1.5 T MR scanner on 23 brain tumor patients [13 cerebral metastases (METs), 10 intracranial meningiomas (MMs), and 9 benign and 1 anaplastic MM] before, and 1, 3, and 7 days after initiation of GCC treatment (dexamethasone 0.26-0.64 mg/kg bw). In addition, 7 patients were studied for 14-63 days of treatment. Imaging analysis included mean T1 of the edema area as a function of time, and an image histogram evaluation technique, which measures 50% of the edema area, where T1 is highest (corresponding to the highest water content of the area), termed the "super-edema." Using a conversion equation, mean T1 in the edema area was recalculated into a percent of tissue water content. After 7 days of GCC treatment total edema area was reduced by 10.3% in the MET patients. The average reduction in mean T1 was 4.6% after 24 h of treatment and 13.5% after 7 days. Expressed in terms of percent tissue water content, the average edema resorption rate in the MET patients was 0.4 +/- 0.1% H2O/day (p < 0.02). Super-edema area was reduced by 64% after 7 days (p < 0.0001). None of the benign MMs responded to GCC treatment, either in edema size or in mean T1, unlike the anaplastic type, in which there was a response comparable to that in the MET patients. The effect of GCCs in up to 63 days of treatment is demonstrated. It is shown that after 40-63 days of GCC treatment, PTE water content is close to the upper normal range for white matter. PTE is heterogeneous in terms of the spatial distribution of T1 and, thereby, water content. GCCs reduce T1 in PTE around cerebral metastases significantly after a few days of treatment, possibly through a mechanism that reduces edema production below the level of edema resorption. PTE surrounding benign MM was not affected by GCC treatment, contrary to one anaplastic MM, which leads to the speculation that malignant tumors may produce substances that are affected by GCCs and are prerequisites for a GCC effect. Significant reductions in the highest T1 area (super-edema area) were observed after 24 h of treatment. The anti-edema effect of GCC may last at least 63 days. A lower dose-dependent threshold for the effect seems to exist. The possible mechanisms of actions of the GCCs on PTE are discussed.
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8040412
|
Metastatic carcinoma to the terminal phalanx of the big toe: report of two cases and review of the literature.
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Metastasis to the distal phalanges of the fingers and toes is rare and is associated with a poor prognosis. Phalangeal metastases commonly display inflammatory symptoms that mimic an acute infection. We describe two men with metastasis to the distal phalanx of the great toe. A review of the literature revealed 118 cases of nonmelanoma metastatic tumors to a distal digit.
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8040411
|
Disseminated strongyloidiasis with cutaneous manifestations in an immunocompromised host.
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Recognition of the characteristic cutaneous eruption of disseminated strongyloidiasis can be crucial for early diagnosis and treatment of this potentially fatal infestation. We describe a corticosteroid-dependent elderly man who had a purpuric eruption. Filariform larvae of Strongyloides stercoralis were found in dermal granulomas and also in the sputum.
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8040410
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Epstein-Barr virus-associated large granular lymphocyte leukemia with cutaneous infiltration.
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A 36-year-old man had a high titer of antibody to Epstein-Barr virus (EBV) and recurrent necrotizing papules and nodules on his face and oral mucosa. The disease was diagnosed as CD3+4- 8+ large granular lymphocyte leukemia of T-cell origin. Southern blot analysis demonstrated that EBV DNA was present in CD8+ lymphocytes; EBV antigens were also observed in these lymphocytes. These findings demonstrated that EBV latently infected the leukemic cells and may have played a role in the pathogenesis of this disease. This is the first report of an association between EBV and large granular lymphocyte leukemia of T-cell origin.
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8040409
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Lipomembranous (membranocystic) changes associated with morphea: a clinicopathologic review of three cases.
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Lipomembranous (membranocystic) changes represent a distinctive form of pathology in adipose tissue. Although first described in the rare neurodegenerative disorder now called Nasu-Hakola disease, this change has also been observed in a variety of relatively common inflammatory and noninflammatory dermatoses. We report three cases of morphea associated with marked lipomembranous (membranocystic) changes in the subcutaneous adipose tissue.
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8040408
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A subtle clue to the histopathologic diagnosis of early alpha 1-antitrypsin deficiency panniculitis.
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An excisional biopsy specimen of a lesion of several days' duration in an 18-year-old woman revealed moderate splaying of neutrophils between collagen bundles throughout the reticular dermis and incipient necrosis of the dermis and subcutaneous fat. Mild infiltration of neutrophils and macrophages was seen in the septal and lobular panniculus. A biopsy performed on one of the patient's more chronic lesions demonstrated dermal necrosis, degeneration and fibrosis of septa, acute lobular panniculitis with a large number of neutrophils, and foci of subcutaneous fat necrosis with islands of sparing. Splaying of neutrophils between the collagen bundles in the reticular dermis appears to be the earliest histopathologic finding of alpha 1-antitrypsin deficiency panniculitis.
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8040407
|
Pedunculated lipofibroma. A clinicopathologic study of thirty-two cases supporting a simplified nomenclature.
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Thirty-two cases are described of a relatively rare form of benign connective tissue proliferation characterized by ectopic fatty tissue in the dermis. The lesions usually appear as large, solitary, slow-growing, pedunculated to dome-shaped, skin-colored nodules or plaques showing predilection for the buttock and upper thigh. Other areas involved include the back, shoulder, knee, neck, and ear. Twenty patients were women and 12 were men, 19 to 78 years of age (mean, 46.9 years). The size of the lesions ranged from 4 to 69 mm (mean, 49 mm). Histologically, the lesions were characterized by the presence of mature adipose tissue infiltrating around the periadnexal adventitial dermis and between adnexal structures and admixing with dense stromal collagen. Marked deposition of mucopolysaccharides was noted in the majority of the lesions. Clinical follow-up in all 32 patients showed no evidence of recurrence. Because of their distinctive clinicopathologic features, we prefer to designate these lesions as solitary, pedunculated lipofibroma. In addition, seven of the patients had diabetes mellitus, suggesting a possible relation between the two conditions.
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8040406
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Double-blind comparison of itraconazole and placebo in the treatment of tinea corporis and tinea cruris.
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Tinea corporis and tinea cruris are usually treated with a topical antifungal agent unless the infection is unresponsive, involves an extensive area, is chronic, or is in a difficult-to-access area. In these cases oral antifungals are frequently used. This double-blind study was undertaken to determine whether a 2-week course of oral itraconazole would produce statistically significant clinical and mycologic improvement in the treatment of tinea corporis, tinea cruris, or both, over the results obtained with placebo. A second objective was to determine the safety of itraconazole, through routine measurements of serum chemistry profiles. Sixty-seven patients were entered into a double-blind, multicenter study to compare the clinical and mycologic effects of itraconazole, 100 mg daily (45 patients), and placebo (22 patients) on tinea corporis and/or tinea cruris. The duration of treatment was 2 weeks. The investigators assessed signs and symptoms and performed a potassium hydroxide examination and culture at baseline, at termination of therapy, and 2 weeks after completion of treatment. Twenty-two (96%) of 23 evaluable patients in the itraconazole group had healed or markedly improved lesions, as compared with 5 of 13 (39%) in the placebo group (p < or = 0.01). Similarly, the condition in 13 of 23 patients (57%) in the itraconazole group was mycologically cleared at the end of treatment whereas this result occurred in only 2 (17%) of 12 patients in the placebo group (p = 0.02). The prevalence of adverse side effects was lower for the itraconazole-treated group (20%) than for the placebo-treated group (36%). Itraconazole 100 mg once daily is an effective agent for the treatment of tinea cruris and tinea corporis.
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8040405
|
Keloids treated with excision followed by radiation therapy.
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In the treatment of keloids surgical excision followed by radiation therapy provides the highest reported control rates of 72% to 92%. We evaluated the effectiveness of excision followed by radiation therapy in the treatment of keloids and compared the efficacy of orthovoltage and electron beam radiation. One hundred twenty-six keloids were treated with radiation therapy after surgical excision. Median follow-up period was 12 years. Recurrence rate, side effects, and effectiveness of therapy were assessed. Data were analyzed with multivariate analysis for significant objective and subjective factors. Higher posttreatment recurrence rates were noted with keloids forming at infected sites and in patients with a family history. No increased likelihood of recurrence was noted with respect to patient age, sex, or ethnicity; keloid size or location; individual keloid history; or prior therapy or radiation type used. Excision followed by radiation therapy is a useful and effective method of keloid eradication, particularly in cases in which lesions are disfiguring or refractory. Electron beam radiation offers no advantage over orthovoltage as a treatment.
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8040404
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Connective tissue tumors in patients with cutaneous melanoma.
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A possible relation between cutaneous melanoma and connective tissue tumors has been described. After the observation that a group of our patients had both cutaneous melanoma and a soft tissue sarcoma, we elected to review this formally. Eleven patients with both diagnoses were identified and are described. A computer search through the Medical Records Department and the Tumor Registry of the Massachusetts General Hospital identified seven men and four women with the diagnoses of melanoma and malignant bone or soft tissue sarcoma. The medical records and pathology specimens of all tumors were reviewed. In three patients, the two tumors were diagnosed within 1 year of each other, in seven, the diagnosis of melanoma was made first, and in one, melanoma was diagnosed after the connective tissue lesion. The interval between the two diagnoses ranged up to 13 years. Although the locations and types of melanoma were typical, some of the connective tissue tumors were unusual; there were two sacral chordomas. In two instances, the melanoma and connective tissue tumor were anatomically close; the sarcoma developed at the edge of the resection of the prior melanoma in one patient. None of the tumors developed in previously irradiated tissues, and in no instance did the second tumor appear to be caused by the therapy received for the first. None of the patients had a family history of melanoma. Four patients had other cancers in addition to the melanoma and connective tissue tumor. Although these patients were seen in a referral center, it is our impression (based on the total number of patients with connective tissue tumors seen and the incidence of melanoma in the general population) that observing 11 patients with both types of tumors is greater than would be expected by chance.
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8040403
|
Eosinophilic pustular folliculitis: a sterile folliculitis of unknown cause?
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Eosinophilic pustular folliculitis (EPF) was initially defined as a sterile folliculitis of unknown cause. Because attempts to demonstrate bacterial organisms have been unsuccessful, and antibiotic therapy is usually ineffective, a bacterial infection is not considered a plausible causative factor for this disease. Our purpose was to describe five patients with the clinical and histologic characteristics of EPF and to report the results of bacterial cultures. Biopsy specimens were examined and pustules were cultured. In three of the five patients, Pseudomonas infection of the hair follicle was the cause of the disease as proven by repeated cultures and the response to specific therapy. Three patients had a systemic disorder known to cause immunologic alteration: AIDS in one and a myeloproliferative disorder in two. Although EPF was initially defined as a sterile folliculitis of unknown origin, three of our patients had an identifiable and treatable cause. We believe that these cases warrant the diagnosis of EPF.
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8040402
|
Clinical and histologic findings in temporal triangular alopecia.
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Temporal triangular alopecia (TTA; also called "congenital triangular alopecia") is a common disorder that is assumed to be congenital. Little is known about its histologic features. Our purpose was to describe four new cases, review the literature, and present histologic features based on vertical and transverse sectioning. The history, clinical features, and histologic findings of four patients with TTA are described and the relevant literature reviewed. Lesions of TTA are seldom congenital, and most are best described as lancet-shaped. The "bald spot" contains normal numbers of hairs, although virtually all are vellus or indeterminate follicles. Most cases of TTA appear to develop during the first few years of life, and the designation "congenital" is a misnomer. The appearance of alopecia can be best explained as a focal zone of hair miniaturization leading to vellus hair formation.
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8040401
|
The burning mouth syndrome: lack of a role for contact urticaria and contact dermatitis.
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The burning mouth syndrome is poorly understood and mainly affects postmenopausal women. Dental allergens have seldom explained the burning. Eight patients (seven women, one man) (mean age 62.5 years) who wore dentures and had the burning mouth syndrome were investigated to determine whether contact urticaria, allergic contact dermatitis, or pressure urticaria played a role. Only patients who had minimal to no erythema of the mucosa were included. A complete blood cell count, fasting chemistry profile, and potassium hydroxide examination and cultures for Candida and dermatophytes were obtained. Contact urticaria and patch testing with control substances were performed with a panel of 25 potential denture allergens. Complete blood cell counts and fasting chemistry profiles were normal. One positive Candida culture was found, but no improvement in the symptoms was noted after treatment. All patients tested positive to histamine and to at least two of the nonimmunologic urticaria controls. No patient had a positive urticarial reaction to the potential dental allergens. Two patients with nonimmunologic urticaria to cinnamic aldehyde improved with avoidance. All patch tests were negative. In the six patients tested for pressure urticaria, the results were negative. We cannot indict contact dermatitis, contact urticaria, or pressure urticaria as a cause of the burning mouth syndrome in the denture-wearing patient who has a normal-appearing mucosa. The burning symptoms in this syndrome may be secondary to a simple frictional phenomenon of the denture on the mucosa.
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8040400
|
An outbreak of tinea corporis gladiatorum on a high school wrestling team.
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An outbreak of tinea corporis occurred in members of a high school wrestling team during the 1992-1993 season. To control the outbreak, we conducted an epidemiologic investigation. We examined 28 team members and obtained skin scrapings from 16. To control the outbreak we recommended (1) griseofulvin for 1 month to treat persons with more than two lesions or any facial lesion(s) and topical ketoconazole or econazole for 1 month to treat all others and (2) that wrestlers be excluded from wrestling until 10 days of topical treatment or 15 days of oral treatment had been completed. Twenty-one wrestlers had lesions consistent with tinea corporis and 10 had Trichophyton tonsurans infection confirmed by culture. A new eruption developed in 12 wrestlers after the recommendations were implemented. This is the third and largest outbreak of tinea corporis gladiatorum to be described in the United States. Appropriate control measures have not yet been established.
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8040399
|
Characterization of nail matrix melanocytes with anti-PEP1, anti-PEP8, TMH-1, and HMB-45 antibodies.
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The normal nail matrix contains quiescent melanocytes with a peculiar arrangement and behavior. Our purpose was to identify nail matrix melanocytes with antibodies that recognize melanocytic cells in tissue sections. We used the polyclonal antibodies anti-PEP1 and anti-PEP8 and the monoclonal antibody TMH-1, which recognize melanocytic enzymes, and the monoclonal antibody HMB-45, which reacts with melanoma cells and fetal melanocytes, but not with normal adult melanocytes. Nail matrix specimens were obtained from longitudinal specimens of eight white patients with ingrown toenails. Specimens from normal adult forearm skin were used as controls. All nail specimens gave similar results. Dendritic melanocytes were more numerous in the distal than in the proximal nail matrix. They were not restricted to the basal layer, but were also found in the suprabasal layers of the nail matrix epithelium. Melanocytes were seen both a single dendritic cells among the nail matrix keratinocytes and as small clusters that appeared irregularly distributed along the length of the nail matrix. Each cluster usually consisted of three to four cells. Even if normally quiescent, nail matrix melanocytes possess the key enzymes responsible for the formation of melanin. The suprabasal location of nail matrix melanocytes may be a consequence of the distribution of adhesion molecules in the nail epithelium. In fact, in the nail matrix alpha 2, alpha 3, and beta 1 integrins are not only expressed on the basal, but also on the fourth to fifth suprabasal layers, with suprabasal expression gradually decreasing from distal to proximal matrix. The behavior of nail matrix keratinocytes may cause the peculiar arrangement and behavior of nail matrix melanocytes.
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8040398
|
Lines of Blaschko.
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The lines of Blaschko represent a pattern followed by many skin disorders. We review the clinical and histologic features of X-linked, congenital/nevoid, and acquired skin diseases that follow these lines. We also include cutaneous disorders that have a linear distribution but do not follow Blaschko's lines. Finally, we differentiate Blaschko's lines from other patterns on the skin such as dermatomes and Langer's lines.
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8040397
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Neuropathological studies on Plasmodium yoelii nigeriensis-induced malaria in mice.
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Malaria infection in mice was produced by intraperitoneal inoculation of 10(6) erythrocytes parasitized with Plasmodium yoelii nigeriensis, a virulent strain of murine malaria. About one week after infection parasitaemia ranged between 60 and 80%, and 100% mortality was observed. Infected animals were killed 6 days after infection to allow the examination of brain tissue. Electron microscopical observations revealed marked damage to cerebral vascular vessel walls with separation of muscular layers, media and adventitia. The endothelial cell layer was discontinuous in places. Activated fibroblast cells producing collagen fibres were seen around the necrotic region of cerebral vasculature. Some parasitized erythrocytes were also seen attached to the endothelial cell lining. Cerebral oedema was prominent around the blood vessels.
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8040395
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Effect of the ingestion of heliotrope and copper on the concentration of zinc, selenium and molybdenum in the liver of sheep.
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Merino wethers were used to examine the effect of feeding heliotrope, with and without additional copper (Cu), on the development of clinical signs, lesions in the liver and concentration in the liver of Cu, zinc (Zn), selenium (Se) and molybdenum (Mo). The feeding of heliotrope reduced liver concentrations of Zn (P < 0.05) and Mo (P < 0.01), but Cu ingestion had no effect on these parameters. The concentration of Se in the liver was only increased when heliotrope was given with copper (P < 0.01); it had previously been shown that Cu and heliotrope ingestion is followed by an interaction which results in a marked increase in the concentration of Cu and the production of extensive lesions in the liver. The increase in liver Se may therefore have represented a passive or active response to liver necrosis, whereas effects on Zn and Mo represented specific metabolic disturbances attributable to heliotrope feeding.
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8040396
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Mucinous hyperplasia in the kidney and ureter of a horse.
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A case of mucinous hyperplasia in the right renal pelvis and ureter is reported in a 23-year-old, male, Quarter horse. The affected right renal pelvis was markedly distended and filled with inspissated yellowish-green mucous material compressing the adjacent cortical and medullary parenchyma. Multiple, similar masses were present protruding from the right urethral mucosa. Histologically, the masses were characterized by a cystic glandular and papillary hyperplasia of the mucosa of the renal pelvis and ureter. This is believed to be the first reported case in an equine species.
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8040394
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Endocardial fibroelastosis in common domestic cats in the UK.
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Endocardial fibroelastosis (EFE) is a pathological disorder characterized by a diffuse and elastic thickening of the endocardium. It is often thought to be congenital as most victims are infants who die of congestive heart failure before reaching one year of age. A naturally occurring animal model of EFE was proposed more than a decade ago on the basis of one pair of adult pure-bred Burmese cats which produced offspring consistently affected with EFE. In the present study a case of EFE is described which occurred in a closed colony of experimental SPF cats. A 5-week-old kitten which was found dead showed hydrothorax, hydropericardium and oedematous lungs at necropsy. Histological examination of the heart revealed left atrio-ventricular dilation with severe, diffuse endocardial thickening which did not extend into the myocardium. A retrospective study was carried out on stored tissues of two further kittens and one adult male cat from the colony which had died during a period of 2 years. The hearts of all the animals showed endocardial thickening in the left atria and ventricle but not in the right chambers. Over a period of 12 years of existence of this colony considerable inbreeding had occurred and it is concluded that an inherited factor was responsible for the disorder.
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8040393
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Numbers of neurons in vacuolated and non-vacuolated neuroanatomical nuclei in bovine spongiform encephalopathy-affected brains.
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Morphometric studies of the brains of seven Holstein-Friesian cows affected with bovine spongiform encephalopathy (BSE) and five control cows are reported. The numbers of neurons were counted in five selected neuroanatomical nuclei, namely the vestibular complex and red nucleus, both of which consistently show a high degree of neuronal perikaryonal vacuolation, the dorsal vagal nucleus, which shows inconsistent perikaryonal vacuolation, and the caudate and hypoglossal nuclei, which do not usually show vacuolation. The vestibular complex of BSE-affected cattle contained about half the number of neurons present in the controls. No statistically significant neuronal loss was demonstrated at other sites. These results confirm previous findings, showing that neuronal loss is a significant feature of BSE and may therefore contribute to the development of the clinical disease. No association was found between the duration of clinical signs and the number of remaining neurons or the extent of the vacuolation. However, the absence of such association should be viewed cautiously as there was substantial variation in neuronal populations between individuals.
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8040392
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Retarded and excessive development of skin appendages in fetal lambs in response to thyroidectomy before wool follicle appearance.
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The impact on wool follicles of development in an athyroid environment was studied in a series of twin fetal lambs by surgically thyroidectomizing one of each pair before the appearance of follicle buds and comparing development of epidermal appendages in it with their development in the normal co-twin. Thyroidectomy was undertaken at 51 to 54 days' gestation, i.e. after approximately one-third of the gestation period. Each treated fetus was then replaced in the uterus, allowing pregnancy to continue. Eight pairs of twins were removed at intervals from 67 to 122 days' gestation and skin samples from the thyroidectomized and the intact twins were compared. Micromorphometric examination of the samples was used to assess quantitatively the effects of thyroid deprivation on wool follicle development. In thyroidectomized fetuses there was a failure of keratinization in primary wool follicles, an absence of secondary follicles, a tendency to excessive follicular branching and sweat gland development, and a paucity of sebaceous gland formation. The density of wool follicles was substantially increased, but the mean cross-sectional area of these follicles was reduced. The effects of very early thyroidectomy imply that the thyroid plays a role in the stimulation and regulation of wool follicle differentiation. To test the reversibility of the effects observed in the skin of thyroidectomized fetuses, grafts from these animals were transplanted to normal, young fetal lambs. Subsequent examination of grafted skin revealed that complete keratinization had occurred but that none of the other abnormal features had been reversed.
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8040391
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Number and size of silver-stained nucleoli (Ag-NOR clusters) in canine seminomas: correlation with histological features and tumour behaviour.
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Twenty spontaneous canine seminomas were examined. A statistically significant difference (P < 0.01) was detected in both the mean silver-stained nucleolar area/cell and the mean silver-stained nucleolar number/cell between (1) two intraductal seminomas with no signs of invasion, and (2) three intraductal ones with signs of invasion and 15 diffuse-type seminomas (two of which metastasized 3 and 12 months after surgical treatment). Furthermore, the metastasizing seminomas showed a mean silver-stained nucleolar area/cell which was significantly greater than that observed in all the other seminomas examined (P < 0.01). It is concluded that quantitative studies of nucleolar changes are useful in evaluating the biological behaviour of spontaneous canine seminomas.
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8040390
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Immunohistochemical detection of neural cell adhesion molecule and laminin in X-linked dystrophic dogs and mdx mice.
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Although dystrophin deficiency is known to be the genetic and biochemical defect causing Duchenne muscular dystrophy (DMD), much remains unknown about the underlying factors affecting clinical and pathological expression of the disease. Two animal forms of muscular dystrophy resembling DMD have been described. Neural cell adhesion molecule (NCAM) and laminin expression were examined in the proliferation-competent mdx mouse and non-regenerative "golden retriever muscular dystrophy dog" (GRMD). The results showed that (1) NCAM expression was greater in dystrophic dogs and mice than in age-matched normal animals, (2) myoblast-specific NCAM was greater in mdx mice than in dystrophic dogs, and (3) laminin strongly labelled mdx and GRMD myofibre membranes but was also sometimes found in individual interstitial cells of mdx muscle. Expression of these proteins may partly determine the clinicopathological expression of dystrophin deficiency.
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8040389
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The pathology of experimental Trypanosoma evansi infection in the Indonesian buffalo (Bubalus bubalis).
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Six Indonesian buffaloes (Bubalus bubalis) were inoculated intravenously with 10(5) Trypanosoma evansi, examined clinically, haematologically and serologically, and then killed 1, 2, 3, 4, 8 or 12 weeks after infection for detailed pathological study. Relapsing fever was related to the waves of parasitaemia and fluctuations of pulse and respiration rates. Anaemic mucous membranes, depression, weakness, refusal to walk, loss of appetite and emaciation were seen. Body weight, packed cell volume, total platelet and red cell counts, and haemoglobin values were below those of two uninfected control buffaloes, as well as below the normal range; on the other hand antibody titres against T. evansi in infected animals were all above those in controls. Emaciation, serous atrophy of fat, hydropericardium, petechial to larger haemorrhages in the pericardium, pneumonia, congested liver and spleen, oedematous enlargement of the superficial lymph nodes and hyperplastic bone marrow were the major gross pathological changes. Histologically, the severity of the disease increased from 1 to 7 weeks after infection and became less obvious at 12 weeks. The most consistent lesions were interstitial pneumonia, interstitial myocarditis, splenic multifocal necrosis, interstitial myositis and hyperplastic bone marrow. The last three lesions appear not to have been reported previously in T. evansi infection in buffaloes or other animals. The clinicopathological findings in this study show that T. evansi is both an intravascular and extravascular parasite.
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8040388
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Silicate pneumoconiosis in pigs: optical and scanning electron microscopical investigations with X-ray microanalysis.
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Four cases of silicate pneumoconiosis are described in pigs raised near several chalk quarries and two cement works. The pulmonary changes were characterized by thickened alveolar septa, resulting in distorted airspaces, and small foci of initial fibrosis. In the bronchiolar and alveolar sites, as in the interstitium, free and intracytoplasmic dust was detected. An energy dispersive X-ray microanalysis coupled with a scanning electron microscope revealed that this dust was composed mainly of silicon, calcium, potassium, sulphur, aluminium and iron. In lung-associated lymph nodes, severe lymphoid cell depletion and dilatation of peritrabecular and subcapsular sinuses were constant findings. The inorganic material found in the lymph nodes contained the elements listed above. Air samples from the same geographical area revealed particulate pollutants, the qualitative features of which were similar to those found in lung and lymph nodal tissue. It is concluded that domestic animals raised in polluted environmental conditions represent an important biological source from which helpful data may be obtained for assessing risks to human health.
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8040387
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In-situ hybridization for demonstration of equine herpesvirus type 1 DNA in paraffin wax-embedded tissues and its use in horses with disseminated necrotizing myeloencephalitis.
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The detection of equine herpesvirus type 1 (EHV-1) in infected cell cultures, and in tissues taken at necropsy, by the in-situ hybridization technique is described. A 4.9 kb Bam HI fragment of EHV-1 vaccine strain RacH was used as a probe after labelling with [alpha-32P] thymidine 5'-triphosphate ([32P]TTP) or digoxigenin-deoxyuridine 5'-triphosphate (dUTP). Both probes specifically detected EHV-1 DNA in either cytospin or paraffin wax-embedded preparations of infected cells. The digoxigenin-labelled probe was further used to examine tissue sections of equine fetuses which had been aborted due to EHV-1 infection. In all cases positive hybridization signals were mainly associated with the nuclei. Positive results were confirmed by immunostaining of EHV-1 antigen in adjacent sections. However, both methods failed to detect EHV-1 in spinal cord sections of six horses suffering from disseminated necrotizing myeloencephalitis (DNM). These results support the hypothesis that DNM is not caused by a productive viral infection of parenchyma of the nervous system but is immunologically mediated.
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8040385
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Haemopoietic spleen colony formation in the rat: effect of 89Sr-induced bone marrow aplasia.
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Regulation of spleen-colony formation, a clonal assay for haemopoietic stem cells, is very different in mice and rats. In the rat, there is an involution of the colony-forming ability of the spleen during infantile development, whereas in mice the ability is maintained throughout life. In our re-evaluation of endogenous spleen colony formation in rats after graded doses of total-body irradiation, colonies ceased to appear after 12 weeks of age. However, histological sections showed that there were tiny colonies growing in the spleen, even at 20 weeks. These microscopical colonies developed into visible colonies when the rats were given treatments that increased the haemopoietic requirement. Thus, the amount of 59FeCl3 incorporated into the spleen increased to compensate for a decrease in uptake by the bone marrow. Rats in which bone-marrow activity was inhibited by 89SrCl2, showed extensive colony formation in the spleen, even after 12 weeks of age, when the endogenous colonies were induced by a sublethal dose of radiation. About twice as much 59Fe acetate activity was incorporated into the spleens of the experimental animals than in those of control rats. These findings imply that spleen-colony formation responds to the haemopoietic requirement of the spleen rather than that of the bone marrow. Furthermore, the requirement of the spleen seems to be much smaller in rats than in mice, because bone-marrow capacity for haemopoiesis is relatively larger in rats.
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8040386
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Respiratory syncytial virus-associated bronchopneumonia in a young chimpanzee.
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A fatal bronchopneumonia in a captive, 14-month-old female chimpanzee (Pan troglodytes) is reported. Clinical, necropsy and histopathological findings, together with immunofluorescence and virus isolation studies implicated respiratory syncytial virus as the causative agent. The probable pathogenesis is discussed.
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8040384
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Experimental infection of vaccinated and non-vaccinated lambs with Mycobacterium paratuberculosis.
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A study of the pathogenesis of paratuberculosis and the effects of vaccination was carried out on 17 Rasa lambs, allocated to four groups. Vaccination seemed to accelerate the progress of the infection, and led quickly to healing. The only site of early lesions was the interfollicular areas in the Peyer's patches. This would suggest an explanation both for the location of paratuberculous lesions in the ileum in clinical cases, and for the lower susceptibility to infection of adult animals, in which the intestinal organized lymphoid tissue is greatly diminished. Thus, a critical role of the Peyer's patch in the establishment of M. paratuberculosis infection is suspected.
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8040383
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Hyperplasia and hypertrophy of B cells in the islets of Langerhans in hamsters infected with the 139H strain of scrapie.
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Previous studies showed that in hamsters the 139H, but not the 263K, scrapie strain caused a marked increase in pancreatic size and led to obesity, hypoglycaemia and striking hyperinsulinaemia. In the preceding paper (Ye et al., 1994), the islets of Langerhans in 139H-affected hamsters showed cellular atrophy, fibrosis, cytoplasmic vesicles and nuclear pathological changes. In the present study, the profiles of pancreatic islets were classified into three sizes with an image analyzer. The number and total area covered by "small" islet profiles were less in 139H-affected than in normal hamsters. In contrast, the number and the area of "medium" and "large" islet profiles were significantly greater in 139H than in normal hamsters. With antibodies to insulin, glucagon, somatostatin and pancreatic polypeptide, the proportions of B, A, D and F cells were determined. With somatostatin-positive cells arbitrarily given a value of 1, the ratio of B:A:D:F cells in the islets was 27:5:1:0.04 in normal hamsters and 122:7:1:0.04 in 139H-affected hamsters. The increase in B cells would account for the islet enlargement and the hypoglycaemia-hyperinsulinaemia seen in 139H-affected hamsters.
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8040382
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Immunopathological study on equine insect hypersensitivity ("kasen") in Japan.
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Equine "kasen" is a chronic dermatitis that occurs especially during the summer months. In the present study, skin lesions of kasen that were collected by biopsy from May to October were classified histopathologically into three stages: initial (Group I, 30 cases), developing (Group II, 48 cases) and regressing (Group III, 13 cases). The characteristic lesions were hyperkeratosis, an increase in the number of T-lymphocytes and Langerhans cells (positive for class II MHC) at the epidermo-dermal junction, oedema of the dermis and perivascular infiltration of eosinophils and mast cells. Ultrastructurally, numerous Birbeck granules were observed in the cytoplasm of Langerhans cells. These lesions were striking in Group II and less so in Group III. Kasen is therefore considered to be similar to Queensland itch and sweet itch as described in Australia and Britain, respectively. The histological features were characteristic of a type I and type IV allergic dermatitis.
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8040381
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Variation in susceptibility of ten mouse strains to infection with a strain of Ehrlichia risticii.
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Eight inbred strains of mice (A/J, AKR/NCrlBR, BALB/cAnNHsd, C3H/HeJ, C3H/HeNHsd, C57BL/6J, C57BL/10SnJ and CBA/J) and two outbred strains (CF1 and ICR) were inoculated with a strain of Ehrlichia risticii and their relative susceptibility to disease was determined. The strains varied widely in susceptibility, some showing profound illness, with illness being barely detectable in others. Severity of illness was uniform within strains. This study confirmed that the A/J and BALB/cAnNHsd strains were very susceptible to illness, but the C3H/HeJ, CBA/J and the CF1 strains were slightly less susceptible. The C57BL/6J, C57BL/10SnJ, C3H/HeNHsd, AKR/NCrlBR and ICR strains were resistant.
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8040380
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Necrotizing meningoencephalitis in pug dogs in Japan.
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This report records necrotizing meningoencephalitis in three pug dogs. It is the first record of the disease in Japan. There were three characteristic histopathological findings, namely (1) a non-suppurative inflammatory cell infiltration of the cerebral hemispheres, including both gray and white matter, (2) meningeal and perivascular infiltrates of mononuclear cells, with a strong tendency to invade the underlying or surrounding brain parenchyma, and (3) selective cerebral cortical necrosis, often occurring without a concurrent inflammatory reaction. The three cases, which were diagnosed as pug dog encephalitis, resembled those previously reported in the United States of America, Switzerland and Italy. All affected animals were females with clinical histories of pregnancy or phantom pregnancy 2 weeks or less before the onset of the clinical signs.
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8040379
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Hepatocarcinogenesis in western mosquitofish (Gambusia affinis) exposed to methylazoxymethanol acetate.
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To assess the potential of western mosquitofish (Gambusia affinis) for the detection of environmental carcinogens, laboratory-reared specimens were exposed to methylazoxymethanol acetate 10 mg per 1 for 2 h and then examined periodically for the onset of neoplastic lesions. Approximately 33 per cent of the exposed fish developed liver neoplasms within 25 weeks of exposure and 52 per cent within 40 weeks. The lesions were mostly hepatocellular carcinomas and cholangiocarcinomas. No neoplastic lesions were detected in other organs. The carcinogen sensitivity and the widespread distribution of the mosquitofish suggest that this species would be useful as a warm water sentinel for environmental contamination.
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8040378
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Gross and histopathological study of endotoxin-induced hoof lesions in cattle.
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In young cattle infusion of Escherichia coli endotoxin resulted in sole and wall haemorrhages that were more severe in the hind than in the fore feet. Histopathological examination of biopsies taken 5 days after infusion showed separation at the tips of the laminae, changes in the vascularity of the dermal papillae and laminae, lightly stained material in the sole horn and degeneration of the epidermal cells of the laminae and papillae. Later, densely stained material in the tubules of the sole, arteriosclerosis in all parts of the corium and proliferative changes in the laminae were seen. It is concluded that endotoxin can induce diffuse aseptic pododermatitis in cattle, characterized by initial degenerative changes in the papillae and laminae followed by proliferative changes in the laminae and arteriosclerosis in all parts of the corium.
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8040377
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Hamartomatous polyps in the intestine of two dogs.
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Partly obstructing, proliferative mucosal masses in the small intestine of two dogs were shown histologically to be hamartomatous polyps. They were characterized by an extension of smooth muscle from the muscularis mucosae into the lamina propria of the lesion. This is the first report of such lesions in domestic animals. In one of the dogs the lesion had become malignant.
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8040376
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Biochemical differences (O-acetyl and glycolyl groups) in erythrocyte surface sialic acids of trypanotolerant N'dama and trypanosusceptible Zebu cattle.
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Differences in the distribution and concentration of O-acetyl and glycolyl groups in erythrocyte sialic acids of trypanotolerant N'dama and trypanosusceptible Zebu cattle were investigated. Erythrocyte surface sialic acid concentrations were 25.4 +/- 5.5 mg per dl and 5.9 +/- 0.97 mg per dl in N'dama and Zebu animals, respectively. In N'damas, O-acetyl and glycolyl groups were present in concentrations of 16.4 +/- 4.3 mg per dl and 12.8 +/- 2.9 mg per dl, respectively, whereas the corresponding values in Zebus were 2.8 +/- 5.0 mg per dl and 7.6 +/- 1.7 mg per dl, respectively. The differences between N'dama and Zebu cattle in surface sialic acids and in O-acetyl and glycolyl groups were significant (P < 0.01 to < 0.001). N'dama erythrocyte sialic acids had more O-acetyl than glycolyl groups while those of Zebus had less O-acetyl than glycolyl groups. These findings may be relevant to the trypanotolerance of N'dama cattle.
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8040375
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Muscular changes in Venezuelan wild horses naturally infected with Trypanosoma evansi.
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Skeletal muscle biopsy specimens were taken from 10 male horses naturally infected with Trypanosoma evansi and from 10 uninfected males. An indirect fluorescent antibody test was used to provide a rapid and reliable indication of infection. Histological, histochemical and transmission electron microscopical techniques were used to examine skeletal muscle. The ultrastructural features in muscle fibres were those usually seen in autoimmune disease, namely fibre and capillary necrosis and mononuclear cell infiltration, consisting of macrophages. Changes in fibre-type percentages did not occur in response to the parasite, but alterations in fibre size and capillary supply were found in the parasitized horses.
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8040374
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Immunohistochemical identification of aetiological agents of systemic bovine zygomycosis.
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The reactivity of a panel of rabbit hyperimmune antisera raised against somatic antigens of three zygomycetes, Absidia corymbifera, Rhizopus oryzae and Rhizomucor (Mucor) pusillus was assessed by crossed immunoelectrophoresis (XIE) and indirect immunofluorescence (IIF) staining of experimentally infected murine tissues. Despite a widespread cross-reactivity of the neat antisera, heterologous absorption rendered antisera monospecific as assessed by XIE. Heterologous absorption also rendered the antisera against R. oryzae and R. (Mucor) pusillus specific by IIF, whereas heterologous absorption of Abs. corymbifera antiserum did not abolish reactivity with R. oryzae. The reactivity of the heterologously absorbed antisera and a murine monoclonal IgG1 antibody against Abs. corymbifera enabled zygomycetes within bovine lesions to be identified. Of 113 zygomycotic lesions of 95 cattle examined, 82 (72.5 per cent) showed a pattern of reactivity compatible with Abs. corymbifera, 21 (18.6 per cent) with R. oryzae, and 5 (4.4 per cent) with R. (Mucor) pusillus. Fungi in four lesions reacted with the monoclonal antibody only, and fungal elements in one lesion showed no reactivity at all. Each of the bovine lesions contained only a single fungal species, but one animal was infected by Abs. corymbifera in the rumen and by R. oryzae in the other stomach compartments. Apart from being the main cause of systemic bovine zygomycosis in Denmark, Abs. corymbifera also seems to be the most pathogenic due to its frequent haematogenous and lymphatic spread (87.8 per cent) as compared with R. oryzae (1.4 per cent) and R. (Mucor) pusillus (5.4 per cent).
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8040373
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The frequent occurrence of thyroid tumours in aged horses.
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Thyroid tumours have been described as "moderately common" in horses, but diseases associated with them are rare and the actual incidence has not been reported. A survey of thyroids from 29 horses aged 12 to 32 years revealed gross lesions in 11 animals, all older than 17. Most lesions were microfollicular adenomas. There was no evidence that the horses suffered from long-standing iodine deficiency or diffuse hyperplasia. Adenomas were more common than hyperplastic nodules and it is unlikely that the former arose from the latter. One thyroid adenocarcinoma was discovered. Progression from thyroid hyperplasia to adenomas and thence to adenocarcinomas has been reported in rodent species, but this study suggests that such progression does not occur in horses. As evidence of its occurrence in man is also lacking, the horse may be a more appropriate model than the rodent for human thyroid neoplasia.
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8040372
|
S100 protein is not specific for myoepithelial cells in the canine mammary gland.
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The distribution of protein S100 in the canine mammary gland was studied, this substance having been described as specific for myoepithelial cells. Two immunohistochemical methods, peroxidase-anti-peroxidase complex (PAP) and alkaline phosphatase-anti-alkaline phosphatase complex (APAAP) were used on frozen sections of normal canine mammary gland. Both the myoepithelial and epithelial cells stained positively with PAP. With APAAP, staining was also seen in the controls, presumably because endogenous alkaline phosphatase was not blocked. As protein S100 was shown to be present both in myoepithelial and epithelial cells of the mammary gland, it was concluded that S100 is not a specific marker for myoepithelial cells.
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8040371
|
The pathology and trace element status of the toxic milk mutant mouse.
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The toxic milk (tx) mouse is a mutant in which copper metabolism is abnormal. Homozygous tx adults do not show overt signs of disease, but litters born to such parents are deficient in copper and die at about 2 weeks of age unless copper is provided. The results reported here clearly indicate that adults accumulate copper in the liver, kidney, spleen, brain, muscle, serum and red blood cells. The concentration of zinc is also elevated in liver, brain and muscle. In adult animals there is damage to hepatocytes with marked changes to the nuclei. Haemolysis occurs with subsequent deposition of haemosiderin in the kidney. This mutant provides a useful model for studies of the pathogenesis and treatment of copper toxicity in animals and man.
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