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41.
A novel DNA virus, TT virus (TTV), has been proposed as a possible etiologic agent for non A-E hepatitis. The aim of the present study was to determine the prevalence of TTV infection using PCR in healthy blood donors and in patients with clotting disorders who have been investigated previously for GBV-C/HGV and HCV infection in Belgium. In this study, PCR using primers proposed by Takahashi et al. [(1998) Hepatology Research 12:233-239] proved far more sensitive than those used by Okamoto et al. [(1998) Journal of Medical Virology 56:128-132]. The sequence of the PCR products showed 87% identity to the published sequence. TTV was present in 29.7% of healthy blood donors, a figure intermediate between the low rate of infection observed in Scotland and the high rates in the Far East. TTV was detected in 46.5% of 127 patients studied with clotting disorders as compared to 79.5% for HCV and 11.8% for GBV-C/HGV infection. However, there was no impact on the level of serum transaminases. Treatment with interferon for HCV infection co-infected with TTV suppressed temporarily serum TTV DNA. Therefore, it was concluded that TTV DNA is detected frequently in serum of healthy blood donors in Belgium and more often in patients with clotting disorders. TTV does not cause liver disease or contribute to the severity of liver disease.  相似文献   
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43.
Adaptive regulation of gene expression in response to environmental changes is a general property of bacterial pathogens. By screening an ordered transposon mutagenesis library of Mycobacterium tuberculosis, we have identified three mutants containing a transposon in the coding sequence or in the 5' regions of genes coding for two-component signal transduction systems (trcS, regX3, prrA). The intracellular multiplication capacity of the three mutants was investigated in mouse bone marrow-derived macrophages. Only the prrA mutant showed a defect in intracellular growth during the early phase of infection, and this defect was fully reverted when the mutant was complemented with prrA-prrB wild-type copies. The mutant phenotype was transient, as after 1 week this strain recovered full growth capacity to reach levels similar to that of the wild type at day 9. Moreover, a transient induction of prrA promoter activity was observed during the initial phase of macrophage infection, as shown by a prrA promoter-gfp fusion in M. bovis BCG infecting the mouse macrophages. The concordant transience of the prrA mutant phenotype and prrA promoter activity indicates that the PrrA-PrrB two-component system is involved in the environmental adaptation of M. tuberculosis, specifically in an early phase of the intracellular growth, and that, similar to other facultative intracellular parasites, M. tuberculosis can use genes temporarily required at different stages in the course of macrophage infection.  相似文献   
44.
Twenty-one patients, including our two cases, with variable clinical phenotype, ranging from mild learning disability to severe congenital malformations or overlapping features with DiGeorge/velocardiofacial syndromes (DG/VCFS), have been shown to have a chromosome duplication 22q11 of the region that is deleted in patients with DG/VCFS. The reported cases have been identified primarily by interphase FISH and could have escaped identification and been missed by routine cytogenetic analysis. Here we report on two inherited cases, referred to us, to rule out 22q11 microdeletion diagnosis of VCFS. The first patient was a 2-month-old girl, who presented with cleft palate, minor dysmorphic features including short palpebral fissures, widely spaced eyes, long fingers, and hearing loss. Her affected mother had mild mental retardation and learning disabilities. The second patient was a 7(1/2)-year-old boy with velopharyngeal insufficiency and mild developmental delay. He had a left preauricular tag, bifida uvula, bilateral fifth finger clinodactyly, and bilateral cryptorchidism. His facial features appeared mildly dysmorphic with hypertelorism, large nose, and micro/retrognathia. The affected father had mild mental retardation and had similar facial features. FISH analysis of interphase cells showed three TUPLE1-probe signals with two chromosome-specific identification probes in each cell. FISH analysis did not show the duplication on the initial testing of metaphase chromosomes. On review, band q11.2 was brighter on one chromosome 22 in some metaphase spreads. The paucity of reported cases of 22q11.2 microduplication likely reflects a combination of phenotypic diversity and the difficulty of diagnosis by FISH analysis on metaphase spreads. These findings illustrate the importance of scanning interphase nuclei when performing FISH analysis for any of the genomic disorders.  相似文献   
45.
Invasive fungal infections have appeared to be increasingly emergent in immunocompromised patients, especially in solid organ transplant (SOT) recipients. The Alternaria genus encompasses more than 80 dematiaceus species. Among them, Alternaria alternata and Alternaria infectoria are the most frequent isolated as responsible for infection in humans.To our knowledge, we report the first case of a heart transplant recipient suffering from subcutaneous nodule caused by Alternaria infectoria and who was treated with isavuconazole. Despite all the promises of this new azole drug, one should keep in mind the potential great variability of the inter-individual responses for such complex patients. We demonstrate herein how it can be challenging to manage Alternaria infection in SOT recipients. More comprehensive studies and recommendations are expected in the context of Alternaria infections.  相似文献   
46.
The aim of this study was to assess the prevalence and the molecular epidemiology of human T-lymphotropic virus type 1 (HTLV-1) in a group of pregnant women living in Guinea Bissau. We studied 427 consecutive pregnant women attending 10 centers for HIV-1 infection monitoring in Bissau. HTLV-1 infection was found in 2.6% of the patients. Phylogenetic analysis of the long terminal repeat region showed that 10 isolates were of the cosmopolitan subtype (HTLV-1a) and that only 1 was of the widespread Central African subtype (HTLV-1b). All the cosmopolitan isolates belonged to the HTLV-1aD subgroup, which was first described in North Africa and clustered with other Senegal and Guinea isolates to form a significant West African clade. Our data show a high prevalence of HTLV-1 in Guinea Bissau and suggest the existence of a trans-Saharan strain distributed in North and West Africa, which probably crossed the desert in the past as a result of contacts between nomadic and sedentary populations or along trading routes.  相似文献   
47.
HIV-associated wasting is defined as > or = 10% involuntary weight loss and includes declines in both lean and fat mass. This large (757 subjects), randomized, double-blind, placebo-controlled trial investigated the efficacy, safety, and tolerability of recombinant human growth hormone (rhGH) in 2 doses-0.1 mg/kg up to a maximum of 6 mg daily (DD) or alternate days (AD)-in the treatment of wasting and weight loss in highly active antiretroviral therapy (HAART)-treated HIV-infected subjects. The evaluable population for ergometry comprised 555 subjects, 87.6% of whom were receiving HAART. At 12 weeks, median maximum work output increased by 2.4 and 2.6 kJ in the AD and DD groups, respectively. The median treatment difference was 2.9 kJ for DD vs. placebo (P < 0.0001). Body weight increased by 2.2 and 2.9 kg in the AD and DD groups, respectively. Corresponding median treatment differences vs. placebo were 1.5 and 2.2 kg (P < 0.0001). Lean body mass (LBM), by bioelectric impedance spectroscopy, increased by 3.3 and 5.2 kg, respectively (P < 0.0001 vs. placebo; P = 0.0173 DD vs. AD), and fat mass, predominately truncal, decreased. Quality of life (QoL) improved significantly in both rhGH groups. Fluid-retention adverse effects and hyperglycemia were more common in the DD than in the AD group. No significant changes in HIV viral load or CD4 cell count occurred. In conclusion, over the 12-week course of therapy, rhGH, 0.1 mg/kg DD, was superior to placebo in improving physical function, body weight, body composition, and QoL and was superior to AD dosing in restoring LBM.  相似文献   
48.
The prevalence of asthma and allergic diseases has been found to be increasingly rapidly, especially in developing countries. Environmental factors have been found to be important contributors to the manifestations of allergic diseases. Air pollution has been extensively studied in different regions of the world. The levels of ambient air pollutants in many Asian countries are very high when compared with those in developed Western countries. However, the prevalence of asthma was relatively low across many Asian countries. Many studies have clearly documented that environmental air pollution is an important factor resulting in exacerbations of asthma. In particular, levels of traffic-related pollutants are increasing rapidly across many Asian countries in parallel with the level of urbanization and economic development. The loss of protective factors associated with a rural environment will further contribute to the adverse effect on patients with allergic diseases such as asthma. In this review the roles of air pollution were examined in relation to the inception and exacerbations of allergic diseases in Asia.  相似文献   
49.
We assessed the regional brain atrophy in mouse lemur primates from 4.7 T T2-weighted magnetic resonance images. Thirty animals aged from 1.9 to 11.3 years were imaged. Sixty-one percent of the 23 animals older than 3 years involved in the study displayed an atrophy process. Cross-sectional analysis suggests that the atrophy follows a gradual pathway, starting in the frontal region then involving the temporal and/or the parietal part of the brain and finally the occipital region. Histological evaluation of five animals selected according to various stages of atrophy suggested that extracellular amyloid deposits and tau pathology cannot explain by themselves this atrophy and that intracellular amyloid deposition is more closely linked to this pathology. This study suggests that most of the age-related atrophy occurring in mouse lemurs is caused by one clinical, evolving, pathological process. The ability to follow this pathology non-invasively by MRI will allow to further characterize it and evaluate its relationship with neuropathological lesions that are involved in human diseases such as Alzheimer.  相似文献   
50.
ObjectiveIn young women, EOC is a rare disease with an uncertain genetic and biological substrate.MethodsWe report a long follow-up of EOC patients treated at Gustave Roussy between 1990 and 2009. We matched young patients aged ≤30 years to randomly selected older patients aged ≥40 years according to known prognostic factors (i.e. FIGO stage, histology and surgical residual disease) and the date of diagnosis with a threshold at the year 2000 to balance the treatment procedures.ResultsEOC was diagnosed in 68 patients aged ≤30 years matched with 111 patients aged ≥40 years. Low-grade (LG) (i.e. serous and endometrioid) (52%, n = 35) and mucinous (i.e. 23%, n = 16 infiltrative and 12% n = 8 expansile) tumors are prevalent. High-grade (HG) tumors are rare (7%, n = 5). Early stage diseases (53%, n = 36 FIGO I/II) are predominant. Response to platinum based chemotherapy is observed to be inferior in young patients as compared to matched older patients (ORR, 29 vs 84% p = 0.0002). For HG tumors the PFS is of 0% at 5 and 10 years in younger as compared to 30% in older patients. No difference in PFS (median 4.9 vs 9.8 ms, p = 0.58) and OS (not reached vs 15.3 ms, p = 0.47) is found overall among younger and older patients respectively. The median follow-up was 72 months (range, 11–288 months). No genetic abnormalities were found.ConclusionsYoung EOC patients are most often diagnosed at an early FIGO stage with LG serous or mucinous histology. Tumors are significantly more resistant to platinum-based chemotherapy in younger patients.  相似文献   
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