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81.
Hepatitis E virus (HEV) is a newly-identified causative agent of acute and chronic hepatitis in severely immunocompromized patients. The present study sought to assess the prevalences of past, recent, on-going, and chronic HEV infections in patients infected with human immunodeficiency virus (HIV) in Marseille, South-eastern France, and to determine if they were correlated with the patients' immunological status or with cirrhosis. Anti-HEV IgG and IgM and HEV RNA testing were concurrently performed on the plasma from 184 patients infected with HIV, including 81 with a CD4+ T-lymphocyte count (CD4 count) <50 cells/mm(3) and 32 with a cirrhosis. Prevalence of anti-HEV IgG and IgM was 4.4% (8/184) and 1.6% (3/184), respectively. Past, recent, and on-going infections were observed in 3.3% (6/184), 1.6% (3/184), and 0.5% (1/184) of the patients, respectively. Anti-HEV antibodies prevalence did not differ significantly according to CD4 count, cirrhosis, sex, age, mode of HIV transmission, and infection with hepatitis B or C virus. Anti-HEV IgG seroreversion was observed in two patients. The patient whose plasma tested positive for HEV RNA had a CD4 count <50 cells/mm(3) ; HEV genotype was 3f. In this patient, longitudinal testing showed HEV RNA positivity during a 10-month period, indicating chronic HEV infection; in contrast, anti-HEV IgG never tested positive. Further studies are needed to evaluate the performance of commercial HEV serological assays in patients infected with HIV and to assess the actual incidence, prevalence, and outcome of HEV infection in this special group of patients. HEV RNA testing is necessary for such purposes.  相似文献   
82.
Accurate HIV-2 plasma viral load quantification is crucial for adequate HIV-2 patient management and for the proper conduct of clinical trials and international cohort collaborations. This study compared the homogeneity of HIV-2 RNA quantification when using HIV-2 assays from ACHI(E)V(2E) study sites and either in-house PCR calibration standards or common viral load standards supplied to all collaborators. Each of the 12 participating laboratories quantified blinded HIV-2 samples, using its own HIV-2 viral load assay and standard as well as centrally validated and distributed common HIV-2 group A and B standards (http://www.hiv.lanl.gov/content/sequence/HelpDocs/subtypes-more.html). Aliquots of HIV-2 group A and B strains, each at 2 theoretical concentrations (2.7 and 3.7 log(10) copies/ml), were tested. Intralaboratory, interlaboratory, and overall variances of quantification results obtained with both standards were compared using F tests. For HIV-2 group A quantifications, overall and interlaboratory and/or intralaboratory variances were significantly lower when using the common standard than when using in-house standards at the concentration levels of 2.7 log(10) copies/ml and 3.7 log(10) copies/ml, respectively. For HIV-2 group B, a high heterogeneity was observed and the variances did not differ according to the type of standard used. In this international collaboration, the use of a common standard improved the homogeneity of HIV-2 group A RNA quantification only. The diversity of HIV-2 group B, particularly in PCR primer-binding regions, may explain the heterogeneity in quantification of this strain. Development of a validated HIV-2 viral load assay that accurately quantifies distinct circulating strains is needed.  相似文献   
83.
Introduction  Hemangiopericytoma is an uncommon soft tissue vascular neoplasm. Intraperitoneal hemangiopericytomas such as primary or secondary liver location have been exceptionally described. Its natural history is mostly benign, but recurrences may occur and determining if these late-discovered tumors are distant metastases or synchronous slow and silent-growing locations is sometimes challenging. The histopathological diagnosis and definition of hemangiopericytoma is based on its distinction with solitary fibrous tumors. Liver resection to treat liver hemangiopericytoma seems to be supported by various published experiences. Case presentation  We herein report the first case of liver metastases from a subcutaneous temporal hemangiopericytoma. The patient was treated by a liver resection. CD34 Immunostaining was negative, but strong expression of Bcl2 and CD99 was found in the neoplastic cells. After 1 year of follow-up, the patient is alive without recurrence. Conclusion  To date, published data, including the case herein reported, support the need for a prolonged follow-up and the role of liver resection to treat liver metastases of hemangiopericytomas. Complete resection of all gross disease appears to be the most significant prognostic factor.  相似文献   
84.
In patients with osteoporosis treated with antiresorptive agents, reduction in bone turnover explains much of the observed fracture risk reduction. Lower levels of bone turnover markers (BTMs) appear to be associated with a lower risk of fracture in bisphosphonate‐treated patients. BTMs were measured in a subset of subjects in the HORIZON Pivotal Fracture Trial. Annual infusions of zoledronic acid 5 mg significantly reduced BTMs: median decrease of 50% for β‐C‐terminal telopeptides of type 1 collagen (β‐CTX), 30% for bone alkaline phosphatase (ALP), and 56% for procollagen type 1 amino‐terminal propeptide (PINP). The mean level of BTMs decreased in treated patients but remained within the premenopausal range before the next injection. The percentage of zoledronic acid–treated patients with values below the premenopausal reference range at all time points was 1.7%, 17.8%, and 19% for bone ALP, CTX, and PINP, respectively. The third injection of zoledronic acid resulted in 60% reduction of β‐CTX within 9–11 days, followed by a gradual increase, indicating the persistence of osteoclastic bone resorption. The association between changes in BTMs and fracture incidence was assessed in 1132 patients who had PINP measurements at baseline and 1 yr. There was no association between low PINP levels at 1 yr and increased fracture incidence. In summary, (1) annual injections of zoledronic acid reduced BTMs in the premenopausal range, with a significant response persisting after the third infusion; and (2) low levels of PINP were not associated with increased fracture risk.  相似文献   
85.
To test the hypothesis that an apoptotic process plays a role in the pathogenesis of cerebral lesions in cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), we examined samples from frontal, temporal, insular, and occipital regions, basal ganglia, and cerebellum from 4 patients with CADASIL, 2 with Binswanger disease, and 3 controls. Apoptotic cells were identified using in situ end labeling and activated caspase 3 immunostaining. Immunolabeling for Notch3, the beta-amyloid protein precursor, and phosphorylated neurofilament protein was performed on successive sections. Apoptosis of vascular cells was markedly increased in status cribrosus in CADASIL, both in basal ganglia and subcortical white matter, suggesting that concomitantly with Notch3 deposition it may play a causative role in the dilatation of Virchow-Robin spaces. Neuronal apoptosis was found in CADASIL, mostly in cortical layers 3 and 5. Its severity correlated semiquantitatively with the extent of ischemic lesions and axonal damage in the underlying white matter. It was more severe in demented patients. Only occasional apoptotic neurons were found in the Binswanger cases and none in the controls. This supports the view that neuronal apoptosis may contribute to cortical atrophy and cognitive impairment in patients with CADASIL and that it may, at least partly, result from axonal damage in the underlying white matter.  相似文献   
86.
BACKGROUND: New tools to better monitor dynamics of human immunodeficiency virus (HIV) transmission are needed. METHODS: National surveillance of newly HIV diagnoses included the collection of dried serum spots to identify both recent infections (<6 months) and HIV serotypes. Multivariate analyses were used to identify factors associated with recent infection and infection with non-B subtypes. RESULTS: Between 2003 and March 2005, 7902 new HIV diagnoses were reported. The overall proportion of recent infections was 24.9% (95% confidence interval, 23.8%-26.0%) and was highest among men who have sex with men (MSM; 46%). Recent infection was associated with being an MSM, <30 years old, of French nationality, and living in Paris. Nearly half of newly HIV-1 diagnoses were with non-B subtypes. The highest proportion of non-B infections was reported among African heterosexual persons (81%), but important proportions were reported among French heterosexual persons (34%) and MSM (12%). Being infected by a non-B subtype was independently associated with being African, <30 years old, heterosexual, and living in Paris. The proportion of HIV-2 infection was 1.9%, and 11 cases of HIV-1 group O infection were identified, mainly among West Africans. CONCLUSIONS: There is evidence of high levels of HIV transmission among MSM in France and transmission of non-B subtypes within the indigenous French population.  相似文献   
87.
The effects of bromocriptine (10 mg/kg), known to inhibit prolactin secretion and lower autoimmune processes, were studied on glucose homeostasis in non-fasted non-obese diabetic mice, a spontaneous model of type 1 diabetes. Hyperglycemia was observed 120 and 240 min after i.p. but not s.c. injection. Bromocriptine administration i.p. led to rapid and marked hyperglycemia characterized by sexual dimorphism with males having higher glycemia than females. Bromocriptine induced a rapid but transient decrease in insulinemia in males only and biphasic increases in glucagon levels and a sustained stimulatory effect on circulating corticosterone in both sexes. Bromocriptine-induced hyperglycemia involved D2-dopaminergic receptors, as demonstrated by the inhibitory effect of the D2-dopamine antagonist, metoclopramide (10 mg/kg). Simultaneous injection of bromocriptine and metoclopramide also blocked the rise in blood corticosterone. In conclusion, by inducing hyperglycemia, i.p. bromocriptine administration to prediabetic autoimmune mice may counteract its beneficial anti-immunostimulatory effects.  相似文献   
88.
Genetics of cavernous angiomas   总被引:5,自引:0,他引:5  
Cerebral cavernous malformations (CCM) are vascular malformations that can occur as a sporadic or a familial autosomal dominant disorder. Clinical and cerebral MRI data on large series of patients with a genetic form of the disease are now available. In addition, three CCM genes have been identified: CCM1/KRIT1, CCM2/MGC4607, and CCM3/PDCD10. These recent developments in clinical and molecular genetics have given us useful information about clinical care and genetic counselling and have broadened our understanding of the mechanisms of this disorder.  相似文献   
89.
90.
Acid-base transport in the renal collecting tubule is mediated by two canonical cell types: the β-intercalated cell secretes HCO(3) by an apical Cl:HCO(3) named pendrin and a basolateral vacuolar (V)-ATPase. Acid secretion is mediated by the α-intercalated cell, which has an apical V-ATPase and a basolateral Cl:HCO(3) exchanger (kAE1). We previously suggested that the β-cell converts to the α-cell in response to acid feeding, a process that depended on the secretion and deposition of an extracellular matrix protein termed hensin (DMBT1). Here, we show that deletion of hensin from intercalated cells results in the absence of typical α-intercalated cells and the consequent development of complete distal renal tubular acidosis (dRTA). Essentially all of the intercalated cells in the cortex of the mutant mice are canonical β-type cells, with apical pendrin and basolateral or diffuse/bipolar V-ATPase. In the medulla, however, a previously undescribed cell type has been uncovered, which resembles the cortical β-intercalated cell in ultrastructure, but does not express pendrin. Polymerization and deposition of hensin (in response to acidosis) requires the activation of β1 integrin, and deletion of this gene from the intercalated cell caused a phenotype that was identical to the deletion of hensin itself, supporting its critical role in hensin function. Because previous studies suggested that the conversion of β- to α-intercalated cells is a manifestation of terminal differentiation, the present results demonstrate that this differentiation proceeds from HCO(3) secreting to acid secreting phenotypes, a process that requires deposition of hensin in the ECM.  相似文献   
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