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51.
Previous studies of hepatitis B e antigen (HBeAg)-expressing transgenic (Tg31e) mice have indicated that the degree of T cell tolerance was epitope specific. For example, T cells specific for residues 120–131 of HBeAg are profoundly tolerant, whereas a proportion of T cells specific for residues 129–140 escape tolerance induction in B10. S × B10-Tg31e mice. To understand the basis for differential tolerance towards two T cell sites on the same self antigen, we characterized T cell recognition of HBeAg by primary T cells and T cell hybridomas derived from HBeAg-Tg and non-Tg mice. The self-reactive T cells surviving in B10-Tg31e mice exhibited a unique fine specificity, albeit still focussed on HBeAg residues 129–140, which could be distinguished from the HBeAg-specific T cell repertoire in non-Tg B10 mice. Further, self-reactive T cells were comprised predominantly of Th2-type cells that preferentially evaded tolerance induction as compared to their Th1 counterparts. Because HBeAg may act as a tolerogen during the vertical transmission of chronic hepatitis B virus (HBV) infection, these results suggest that a predominance of HBeAg-specific Th2 cells expressing a limited repertoire may influence the initiation or the maintenance of the HBV chronic carrier state.  相似文献   
52.
We detected 3 genotypes of highly pathogenic avian influenza A(H5N8) virus in France during winter 2016–17. Genotype A viruses caused dramatic economic losses in the domestic duck farm industry in southwestern France. Our phylogenetic analysis suggests that genotype A viruses formed 5 distinct geographic clusters in southwestern France. In some clusters, local secondary transmission might have been started by a single introduction. The intensity of the viral spread seems to correspond to the density of duck holdings in each production area. To avoid the introduction of disease into an unaffected area, it is crucial that authorities limit the movements of potentially infected birds.  相似文献   
53.
We report 3 cases of Puumala virus infection in a family in Switzerland in January 2019. Clinical manifestations of the infection ranged from mild influenza-like illness to fatal disease. This cluster illustrates the wide range of clinical manifestations of Old World hantavirus infections and the challenge of diagnosing travel-related hemorrhagic fevers.  相似文献   
54.
Human bornavirus encephalitis is a severe and often fatal infection caused by variegated squirrel bornavirus 1 (VSBV-1) and Borna disease virus 1 (BoDV-1). We conducted a prospective study of bornavirus etiology of encephalitis cases in Germany during 2018–2020 by using a serologic testing scheme applied along proposed graded case definitions for VSBV-1, BoDV-1, and unspecified bornavirus encephalitis. Of 103 encephalitis cases of unknown etiology, 4 bornavirus infections were detected serologically. One chronic case was caused by VSBV-1 after occupational-related contact of a person with exotic squirrels, and 3 acute cases were caused by BoDV-1 in virus-endemic areas. All 4 case-patients died. Bornavirus etiology could be confirmed by molecular methods. Serologic testing for these cases was virus specific, discriminatory, and a practical diagnostic option for living patients if no brain tissue samples are available. This testing should be guided by clinical and epidemiologic suspicions, such as residence in virus-endemic areas and animal exposure.  相似文献   
55.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Schon in der frühen Phase der global sehr verschieden verlaufenden COVID-19-Pandemie zeigten sich Hinweise auf den Einfluss...  相似文献   
56.
Neurosurgical Review - In the context of hydrocephalus, there are a multitude of therapeutic options that can be explored in order to improve patient outcomes. Although the peritoneum is the...  相似文献   
57.
Reduced bone mineral density (BMD; ie, Z-score ≤−2.0) occurring at a young age (ie, premenopausal women and men <50 years) in the absence of secondary osteoporosis is considered early-onset osteoporosis (EOOP). Mutations affecting the WNT signaling pathway are of special interest because of their key role in bone mass regulation. Here, we analyzed the effects of relevant LRP5 and LRP6 variants on the clinical phenotype, bone turnover, BMD, and bone microarchitecture. After exclusion of secondary osteoporosis, EOOP patients (n = 372) were genotyped by gene panel sequencing, and segregation analysis of variants in LRP5/LRP6 was performed. The clinical assessment included the evaluation of bone turnover parameters, BMD by dual-energy X-ray absorptiometry, and microarchitecture via high-resolution peripheral quantitative computed tomography (HR-pQCT). In 50 individuals (31 EOOP index patients, 19 family members), relevant variants affecting LRP5 or LRP6 were detected (42 LRP5 and 8 LRP6 variants), including 10 novel variants. Seventeen variants were classified as disease causing, 14 were variants of unknown significance, and 19 were BMD-associated single-nucleotide polymorphisms (SNPs). One patient harbored compound heterozygous LRP5 mutations causing osteoporosis-pseudoglioma syndrome. Fractures were reported in 37 of 50 individuals, consisting of vertebral (18 of 50) and peripheral (29 of 50) fractures. Low bone formation was revealed in all individuals. A Z-score ≤−2.0 was detected in 31 of 50 individuals, and values at the spine were significantly lower than those at the hip (−2.1 ± 1.3 versus −1.6 ± 0.8; p = .003). HR-pQCT analysis (n = 34) showed impaired microarchitecture in trabecular and cortical compartments. Significant differences regarding the clinical phenotype were detectable between index patients and family members but not between different variant classes. Relevant variants in LRP5 and LRP6 contribute to EOOP in a substantial number of individuals, leading to a high number of fractures, low bone formation, reduced Z-scores, and impaired microarchitecture. This detailed skeletal characterization improves the interpretation of known and novel LRP5 and LRP6 variants. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
58.
Previously, we demonstrated low-dose antithymocyte globulin (ATG) and granulocyte colony-stimulating factor (GCSF) immunotherapy preserved C-peptide for 2 years in a pilot study of patients with established type 1 diabetes (n = 25). Here, we evaluated the long-term outcomes of ATG/GCSF in study participants with 5 years of available follow-up data (n = 15). The primary end point was area under the curve (AUC) C-peptide during a 2-h mixed-meal tolerance test. After 5 years, there were no statistically significant differences in AUC C-peptide when comparing those who received ATG/GCSF versus placebo (P = 0.41). A modeling framework based on mean trajectories in C-peptide AUC over 5 years, accounting for differing trends between groups, was applied to recategorize responders (n = 9) and nonresponders (n = 7). ATG/GCSF reponders demonstrated nearly unchanged HbA1c over 5 years (mean [95% CI] adjusted change 0.29% [–0.69%, 1.27%]), but the study was not powered for comparisons against nonresponders 1.75% (–0.57%, 4.06%) or placebo recipients 1.44% (0.21%, 2.66%). These data underscore the importance of long-term follow-up in previous and ongoing phase 2 trials of low-dose ATG in recent-onset type 1 diabetes.  相似文献   
59.
Annals of Surgical Oncology - The aim of this study was to report outcomes following percutaneous microwave and cryoablation of lung metastases from adenoid cystic carcinoma (ACC) of the head and...  相似文献   
60.
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