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Composite tumors containing pheochromocytoma and ganglioneuroma are rare tumors typically arising in the adrenal glands. Very few were reported outside of the adrenals. We present the case of a middle-aged woman with a retroperitoneal mass that was discovered when she complained of local signs of compression and systemic signs of catecholamine hypersecretion. On pathology the mass was composed of large polygonal and pleomorphic cells arranged in nests characteristic of pheochromocytoma that were mixed with clusters of mature ganglion cells and bundles of spindle cells characteristic of ganglioneuroma. The histological features were benign, but due to its invasion of the inferior vena cava and of the right renal artery, we had concerns about the malignant potential of the pheochromocytoma component, which is extremely rare in these composite tumors.  相似文献   
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Convex endobronchial ultrasound (C-EBUS)–guided transbronchial needle aspiration (TBNA) is an effective tool for the diagnosis of hilar, mediastinal, and central parenchymal lung lesions. However, it has a limited utility for pleural-based masses. We report a unique case of a pleural synovial sarcoma recurrence that was diagnosed by C-EBUS.The patient had a history of inguinal synovial sarcoma. He presented with cough and chest pain. Imaging of chest revealed large right pleural mass. Bronchoscopy with EBUS-TBNA diagnosed pleural recurrence of synovial sarcoma. He underwent radical resection and pathological examination confirmed the diagnosis of pleural synovial sarcoma. He experienced complete recovery and resolution of symptoms.Synovial sarcoma should be included in the differential diagnosis of pleural masses. Convex EBUS-guided biopsies can provide adequate diagnosis of large pleural tumors adjacent to the central airways without need for more invasive diagnostic procedures.  相似文献   
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Background

Microglia are major players in the pathogenesis of multiple sclerosis (MS) and may play a dual role in disease progression. The activation status of microglia in vivo is highly dynamic and occurs as a continuum, with the pro-inflammatory and anti-inflammatory phenotypes on either end of this spectrum. Little is known about in vivo dynamics of microglia phenotypes in MS due to the lack of diagnostic tools. Positron emission tomography (PET) imaging is a powerful non-invasive technique that allows real-time imaging of microglia activation phenotypes in the central nervous system, depending on the availability of selective PET tracers. Our objective is to investigate and characterize the expression of the purinergic receptors P2Y12R and P2X7R as potential targets for PET tracer development and subsequent PET imaging in order to evaluate the dynamics of microglia status in vivo.

Methods

We used immunohistochemical analysis to explore the expression of P2Y12R and P2X7R in experimental autoimmune encephalomyelitis (EAE) post-mortem tissues and different stages of well-characterized MS lesions. We evaluated by quantitative real-time polymerase chain reaction the expression of P2Y12R and P2X7R in human polarized microglia, and we performed autoradiography binding assay with radiolabeled P2Y12R and P2X7R antagonists using MS and rat EAE tissues.

Results

Here, we demonstrate that P2X7R is associated with a pro-inflammatory phenotype of human microglia in vitro, and is highly expressed in microglia in MS lesions as well as during the peak of EAE. In contrast, P2Y12R was associated with an anti-inflammatory phenotype in human microglia in vitro and was expressed at lower levels in active inflammatory MS lesions compared to normal-appearing white matter (NAWM) and similarly in EAE, while its expression increased in the remission phase of EAE. Binding of radiolabeled tracers specific for P2Y12R and P2X7R on ex vivo tissues validated the value of these receptors as PET imaging targets for microglia phenotypes in vivo.

Conclusion

Our results suggest that P2Y12R and P2X7R are excellent targets for PET imaging to discriminate distinct microglia phenotypes in MS. Ultimately, this may provide insight into the role of microglia in disease progression and monitor novel treatment strategies to alter microglia phenotype.
  相似文献   
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Our aim was to investigate the long term effectiveness of intravenous immunoglobulin (IVIG) against intractable childhood epilepsy in the era of new antiepileptics and to determine the predictors of a favorable response in a prospective open-label add-on study. Of thirty-seven 9.9 ± 0.9-year-old patients (11 with partial seizures, 26 with generalized seizures of whom 9 had West syndrome and 17 Lennox–Gastaut syndrome) followed for 15 ± 3 months, 43% had a >50% decrease in seizures (including 15% seizure free, 229 ± 58 compared with 104 ± 3 seizures/month, P = 0.035: generalized 246 ± 318 to 117 ± 200, P = 0.025, partial 191 ± 437 to 72 ± 179, P > 0.05; power = 0.2). Males were more likely to respond than females (P = 0.011, odds ratio = 9.3). Review of the literature revealed nine other articles reporting efficacy of IVIG against epileptic seizures. Only one other used statistical methods and, unlike ours, showed only a trend toward seizure frequency reduction without achieving statistical significance, presumably because it was underpowered. These results indicate large-scale controlled studies of IVIG in epilepsy are still needed.  相似文献   
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BACKGROUND: Annular pancreas is rare; only 737 cases have been reported in the English literature. In addition, no large analysis has compared children and adults. Recently, prenatal diagnosis and advances in imaging have led to increased experience with this condition. STUDY DESIGN: Data from 103 patients (48 children, 55 adults) with annular pancreas, managed from 1992 to 2006, were reviewed. Patients with isolated duodenal atresia, stenosis, or webs were excluded. RESULTS: Median ages at diagnosis were 1 day in children and 47 years in adults. Annular pancreas was more common in girls and women (children, 58%; adults, 69%). Congenital anomalies were more frequent (p < 0.01) in children (71%) than in adults (16%); Down syndrome, cardiac, and intestinal anomalies were most common. Prenatal diagnosis was suspected in 56% of infants, and adults presented with pain (75%), vomiting (24%), pancreatitis (22%), or abnormal liver tests (11%). All children were managed with duodenal bypass. Children were more likely (p < 0.01) to require surgery for associated anomalies. In contrast, adults had fewer duodenal bypass procedures (24%) but more often required endoscopic pancreatobiliary procedures (67%), cholecystectomy (56%), and other pancreatobiliary surgery (20%; p < 0.01). Adults more commonly (p < 0.01) had pancreas divisum (29%) and pancreatobiliary neoplasia (11%). Five children (6%) with multiple anomalies died; all adults survived their operations. Late deaths occurred in 2 children (4%) with multiple anomalies and 3 adults (5%) with pancreatobiliary cancer. CONCLUSIONS: Annular pancreas is associated with a spectrum of disease that differs in children and adults. Congenital anomalies are more common in children with annular pancreas; complex pancreatobiliary disorders and malignancy are more frequent in adults.  相似文献   
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The impact of gender on the presenting characteristics, management, and outcomes in infective endocarditis (IE) has not been adequately studied. The goal of our study was to better understand differences in management and outcome of IE between genders. Data were obtained prospectively from 439 patients in the Duke Endocarditis Database from 1996 to 2004. Baseline characteristics of patients were examined using univariable analysis. Variables associated with gender, in-hospital surgery and long-term mortality in patients with IE were considered for multivariable analysis. Hemodialysis, diabetes mellitus, and immunosuppression were more frequent in female patients with IE. Intracardiac abscesses and new conduction abnormalities were more common in male patients. The following factors were predictive of short-term mortality through univariable analysis: female gender, age, diabetes mellitus, septic pulmonary infarcts, intracranial hemorrhage, infection with Staphylococcus aureus, and persistently positive blood cultures. Female gender was not associated with mortality in an adjusted analysis of short-term outcome. Age, diabetes mellitus, renal failure requiring hemodialysis, cancer, pulmonary edema, systemic embolization, persistently positive blood cultures, and chronic indwelling central catheters but not female gender were associated with long-term mortality using univariable and an adjusted analysis. In both analyses, surgery was associated with improved mortality. Female gender, a history of diabetes mellitus, hemodialysis, and immunosuppression therapy were predictive of a medical management without the use of surgery, although in the adjusted analysis there was no association between surgery and gender. In conclusion, differences between genders in treatment and outcomes frequently reported in patients with IE most likely result from pre- and co-existing conditions such as diabetes mellitus, renal failure requiring hemodialysis, and chronic immunosuppression.  相似文献   
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INTRODUCTIONInfected abdominal aortic aneurysms (AAAs) can present insidiously with non-specific symptoms or they may present as ruptured AAA in the classical manner.PRESENTATION OF CASEWe report two cases of mycotic AAA with Listeria monocytogenes. One patient presented with a ruptured aneurysm, while the other patient had a symptomatic non-ruptured presentation with computer tomography (CT) angiogram demonstrating peri-aortic inflammatory change of a rapidly expanding aneurysm. Both patients were treated with excision of the infected tissue and inlay prosthetic surgical repair as well as long term antibiotics.DISCUSSIONArterial aneurysms caused by L. monocytogenes are rare. Risk factors include immunosuppression, infective endocarditis, intravenous drug use and septicaemia. Listeria infections should be discussed with the Health Protection Agency and local microbiologists due to their ubiquity.CONCLUSIONAbdominal aortic aneurysm due to L. monocytogenes is best managed via surgical resection in combination with long term antimicrobial therapy. The role of endovascular exclusion is unclear.  相似文献   
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