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51.
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Coxsackievirus B4 (CB4) is a picornavirus associated with a variety of human diseases, including neonatal meningoencephalitis, myocarditis and type 1 diabetes. We report the pathological findings in twin newborns who died during an acute infection. The twins were born 1 month premature but were well and neurologically intact at birth. After a week they developed acute lethal neonatal sepsis and seizures. Histopathology demonstrated meningoencephalitis and severe myocarditis, as well as pancreatitis, adrenal medullitis and nephritis. Abundant CB4 sequences were identified in nucleic acid extracted from the brain and heart. In situ hybridization with probes to CB4 demonstrated infection of neurons, myocardiocytes, endocrine pancreas and adrenal medulla. The distribution of infected cells and immune response is consistent with reported clinical symptomatology where systemic and neurological diseases are the result of CB4 infection of select target cells.  相似文献   
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Sixteen chronic (M = 5 years) weekly cocaine users who were at least 10 days (M = 20 days) abstinent were compared to age, education, race, and gender matched controls on the California Verbal Learning Test, Wechsler Adult Intelligence Scale-Revised (WAIS-R) Vocabulary, and Block Design. Subjects with developmental disorder, neurological, psychiatric, or other substance abuse history were excluded. Cocaine subjects learned and recalled fewer words than controls, but did not differ on IQ. Results suggested significant residual impairment in verbal learning efficiency subsequent to chronic cocaine use that results from memory storage difficulties rather than attentional impairment or general intellectual reduction. A dose-response relationship is suggested.  相似文献   
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Previous studies have demonstrated that de novo cholesterol synthesis is increased two- to threefold in the intestines of diabetic animals. This increase is due to a stimulation of cholesterogenesis in both the small and large intestine but, quantitatively, the small intestine is primarily responsible for the observed increase. The present study examined the effect of cholesterol feeding and alterations of bile acid homeostasis on de novo sterol synthesis in intact normal and diabetic animals. Cholesterol feeding in the control animals did not affect sterol synthesis in the small intestine, but in diabetic animals cholesterol feeding markedly inhibited small intestinal sterologenesis. The threefold stimulation of small intestinal sterol synthesis observed in diabetic animals is completely obliterated by cholesterol ingestion. Moreover, this inhibition of sterol synthesis by cholesterol feeding in the small intestine of diabetic animals occurred very rapidly (within 36 h). In the large intestine, cholesterol feeding did not influence sterol synthesis in either the diabetic or control animals. In the liver, cholesterol feeding markedly inhibited sterol synthesis to similar degrees in the diabetics and controls. Colestipol feeding and biliary drainage, procedures that reduce bile acid pool size, stimulated sterol synthesis in the liver and small intestine of both diabetic and control animals. However, reductions in bile acid pool size increased sterologenesis in the large intestine in control animals but had no effect in the diabetics. Bile acid ingestion did not alter either small or large intestinal sterologenesis in the diabetic or control animals. In conclusion, the present study demonstrates the sterol synthesis is enhanced in the small and large intestine of diabetic animals and, moreover, both the cholesterol- and bile acid-mediated regulation of cholesterol synthesis in the intestines of the diabetic animals is altered from normal.  相似文献   
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Vibrio vulnificus is the leading cause of death in the United States associated with the consumption of raw seafood, particularly oysters. In epidemiological studies, primary septicemia and inflammation-mediated septic shock caused by V. vulnificus is strongly associated with liver disease, often in the context of chronic alcohol abuse. The present study was undertaken to determine whether clinical biomarkers of liver function or cellular oxidative stress are associated with peripheral blood mononuclear cell inflammatory cytokine responses to V. vulnificus. Levels of interleukin-1 beta (IL-1 beta), IL-6, IL-8, and tumor necrosis factor alpha elicited in response to V. vulnificus and measured in cell supernatants were not associated with the liver biomarkers aspartate aminotransferase (AST) or alanine aminotransferase (ALT) or the AST/ALT ratio. In contrast, reduced glutathione (GSH) levels were associated with the release of all four cytokines (IL-1 beta [R(2) = 0.382; P = 0.006], IL-6 [R(2) = 0.393; P = 0.005], IL-8 [R(2) = 0.487; P = 0.001], and TNF-alpha [R(2) = 0.292; P = 0.021]). Those individuals with below-normal GSH levels produced significantly less proinflammatory cytokines in response to V. vulnificus. We hypothesize that persons with markers for cellular oxidative stress have increased susceptibility to V. vulnificus septicemia.  相似文献   
58.
The February COM. A 53-year-old obese man presented with new onset seizures and an MRI scan revealed a large cystic and necrotic heterogeneously enhancing left frontal mass. Craniotomy revealed a firm subdural tumor on the cortical surface that was delivered en-bloc preserving the pial planes and stripping it from the falx cerebri. The tumor consisted of multiple irregular fragments of white-tan rubbery tissue admixed with globules of bosselated, white-tan rubbery tissue and a fragment of bone. Sections of the tumor revealed mature hyaline cartilage with no atypia of the chondrocytes. There was focal mineralization and endochondral ossification. A diagnosis of intracranial mesenchymal osteochondroma was made. Osteochondroma, a benign cartilaginous neoplasm comprised of mature hyaline cartilage with focal ossification, is the most common benign bone tumor. Extraskeletal (mesenchymal) osteochondromas are known to originate from non-skeletal or non-cartilaginous tissue. Intracranial osteochondromas are uncommon, typically arising from the base of the skull. Only about 15% of intracranial osteochondromas arise supratentorially, from the dura, usually in a parafalcine frontoparietal location and some have been a component of Maffucci's syndrome and Ollier disease. Intracranial osteochondromas can occur at any age with a predilection for younger individuals. Intracranial mesenchymal osteochondromas exhibit a benign clinical course. Typically, the histomorphology resembles mature hyaline cartilage without anaplastic proliferation of chondrocytes or nuclear atypia, with a lobular arrangement of clusters of lacunae containing single chondrocytes. Transition to osteochondrosarcoma has rarely been documented.  相似文献   
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Microglia constitute the primary resident immune surveillance cell in the brain and are thought to play a significant role in the pathogenesis of several neurodegenerative disorders, such as Alzheimer's disease, multiple sclerosis, Parkinson's disease and HIV-associated dementia. Measuring microglial activation in vivo in patients suffering from these diseases may help chart progression of neuroinflammation as well as assess efficacy of therapies designed to modulate neuroinflammation. Recent studies suggest that activated microglia in the CNS may be detected in vivo using positron emission tomography (PET) utilizing pharmacological ligands of the mitochondrial peripheral benzodiazepine receptor (PBR (recently renamed as Translocator protein (18 kDa)). Beginning with the molecular characterization of PBR and regulation in activated microglia, we examine the rationale behind using PBR ligands to image microglia with PET. Current evidence suggests these findings might be applied to the development of clinical assessments of microglial activation in neurological disorders.  相似文献   
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