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ObjectiveNeopterin is an activation marker for monocytes/macrophages, and circulating levels of neopterin are elevated in patients with coronary complex lesions in unstable angina pectoris. We investigated the possible association between neopterin and complex carotid plaques which may be associated with the risk of ischemic stroke in patients with stable angina pectoris (SAP).MethodsWe measured plasma levels of neopterin in 102 patients with SAP and carotid ultrasound was performed for evaluation of the presence of carotid plaques and plaque surface characteristics categorized as complex or noncomplex. In addition, endarterectomy specimens of extracranial high-grade carotid stenosis with complex plaques from five patients with SAP were immunohistochemically examined with antibodies to smooth muscle cells, endothelial cells, platelets, macrophages, and T cells.ResultsPlasma neopterin levels were significantly higher in patients with complex carotid plaques than in those with noncomplex plaques (median [interquartile range]: 24.2 [19.2–39.3] nmol/L vs. 19.4 [11.9–25.1] nmol/L; P = 0.01) or without any plaques (18.8 [14.9–23.6] nmol/L; P = 0.001). On multivariate logistic analyses after adjustment for traditional atherosclerotic risk factors, multi-vessel coronary disease and high sensitivity C-reactive protein, neopterin levels were independently associated with the presence of complex carotid plaques (adjusted OR 2.21 per SD increase, 95%CI 1.13–4.33, P = 0.02). Immunohistochemical staining revealed abundant neopterin-positive macrophages in carotid complex lesions.ConclusionThese findings demonstrate that carotid plaques with complex morphology have increased circulating neopterin levels and immunohistochemical localization of neopterin in patients with SAP. Neopterin can be considered an important biomarker of plaque destabilization in carotid artery atherosclerotic lesions in this population.  相似文献   
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Yamada C  King KE  Ness PM 《Transfusion》2008,48(6):1245-1255
Persistent corneal epithelial defects (CEDs) are caused by many diseases that are usually associated with decreased production of tears or reduced corneal sensitivity. Although surgical treatments are available for severe cases, CEDs are still difficult for ophthalmologists to treat. One treatment for CEDs that is uncommonly used in the United States is autologous serum eyedrops (ASEs). The first application of ASEs was described in 1984. This landmark report was followed by multiple studies that carefully evaluated the epithelial-promoting properties of ASEs and refined the means of ASE preparation. A number of clinical studies suggested the efficacy of ASEs in various ophthalmologic conditions. This article reviews the efficacy and complications of ASE use reported in these studies. Given that ophthalmologists may consult the blood bank to request ASEs, transfusion medicine physicians should be aware of the issues related to ASE preparation, storage, and potential utility.  相似文献   
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Dysfunction of the frontal-subcortical circuits has been the most common finding in the pathophysiology of obsessive-compulsive disorder (OCD), and recent neuropsychological studies have shown cognitive impairments in OCD. To clarify the pathophysiology of OCD without the confounding effects of medication, we investigated the alterations of brain function in OCD patients and changes after clinical improvement due solely to behavior therapy. The participants were 11 outpatients with OCD and 19 normal controls. The patients received 12 weeks of behavior therapy. We investigated the differences in the behavioral performance and functional magnetic resonance imaging results during the Stroop test in the patients and normal controls, and their changes after treatment in the patients. The patients showed less activation in the anterior cingulate gyrus and cerebellum than control subjects. Following significant improvement in OC symptoms, the cerebellum and parietal lobe showed increased activation, and the orbitofrontal cortex, middle frontal gyrus, and temporal regions showed decreased activation during the Stroop task, and performance of the task itself improved. Our findings suggest that dysfunction of the posterior brain regions, especially the cerebellum, is involved in the pathogenesis of OCD, and that normalization in function can occur with improvement of OC symptoms.  相似文献   
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Adenomyoepithelioma is an uncommon primary breast tumor. It is conspicuous for two elements of the tumor, namely, ductal and myoepithelial components. Recently, a Mammotome biopsy, or stereotactic vacuum-assisted biopsy has become popular and various benign or borderline lesions are obtained. We report an adenomyoepithelioma of the breast in a 56-year-old woman. She was pointed out to have a cluster of some microcalcifications on mammography and a 9-mm hypoechoic mass lesion was detected by ultrasound. A Mammotome biopsy revealed a well-defined lesion. Histologically, the tumor demonstrated a thick and bi-cellular growth pattern consisting of ducts and myoepithelium. Immunohistochemically, epithelial cells were positive for cytokeratin AE1/AE3 and cytokeratin, epithelial membrane antigen (EMA), and carcinoembryonic antigen (CEA), negative for alpha-smooth muscle actin (alpha-SMA). In addition, myoepithelial cells were positive for alpha-SMA and CEA, which were scatterly positive for cytokeratin AE1/AE3, and negative for EMA. In examinations of non-palpable lesions found on mammography and ultrasound, a Mammotome biopsy is useful for making diagnosis, however, and adenomyoepithelioma is rarely found. In diagnosing such a rare disease from the limited information obtained from a needle biopsy, an immunohistochemical study was thus found to be useful for making a differential diagnosis.  相似文献   
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Recently, endothelial dysfunction induced by an uncoupling of vascular endothelial growth factor (VEGF) and nitric oxide has been implicated in the pathogenesis of diabetic nephropathy (DN). Investigating the pathogenesis of DN has been limited, however, because of the lack of animal models that mimic the human disease. In this report, pancreatic beta cell-specific calmodulin-overexpressing transgenic (CaMTg) mice, a potential new model of DN, are characterized with particular emphasis on VEGF and related molecules. CaMTg mice developed hyperglycemia at 3 wk and persistent proteinuria by 3 mo. Morphometric analysis showed considerable increases in the glomerular and mesangial areas with deposition of type IV collagen. Moreover, the pathologic hallmarks of human DN (mesangiolysis, Kimmelstiel-Wilson-like nodular lesions, exudative lesions, and hyalinosis of afferent and efferent arteries with neovascularization) were observed. In addition, increased VEGF expression was associated with an increased number of peritubular capillaries. Expression of endothelial nitric oxidase synthase was reduced and that of VEGF was markedly elevated in CaMTg mice kidney compared with nontransgenic mice. No differences in VEGF receptor-1 or VEGF receptor-2 expression were observed between CaMTg mice and nontransgenic kidneys. In summary, CaMTg mice develop most of the distinguishing lesions of human DN, and the elevated VEGF expression in the setting of diminished endothelial nitric oxide synthase expression may lead to endothelial proliferation and dysfunction. This model may prove useful in the study of the pathogenesis and treatment of DN.  相似文献   
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