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41.
Aseptic meningitis is a frequent diagnosis in emergency departments. Nevertheless, viral investigations are not carried out currently and the viral etiology in adult population has not been studied extensively. We conducted a prospective study including all consecutive patients undergoing lumbar puncture during a 15 months period in an adult emergency department. Bloody and purulent cerebrospinal fluid (CSF) were excluded. The main tests undertaken were: CSF genomic amplification by the polymerase chain reaction (PCR) for neurotropic viruses and serum and CSF interferon-alpha (IFN-alpha) measurements. Among 194 patients included, 45 had and 149 did not have aseptic meningitis. Of 45 patients with aseptic meningitis, 10 had alternative non-virological final diagnosis, and 35/45 were presumed to have neurological disorders of viral origin. Patients (27/35) completed virological analysis: 21/27 (78%) had either positive viral PCR (enterovirus: 8 patients, Varicella zoster virus (VZV): 5, Epstein-Barr virus (EBV): 2, herpes simplex virus (HSV): 1, human herpes virus 6: 1) or only raised serum or CSF IFN-alpha (4 patients). Overall, 59% of patients with a positive viral PCR had either CSF or serum raised IFN-alpha. Twentyone patients without meningitis had either positive viral PCR (enterovirus: 3 patients) or only high serum IFN-alpha level (18 patients). In the setting of aseptic meningitis diagnosed in an adult emergency department, viruses are the most common agents encountered, with enterovirus and VZV as the two main etiological agents. Current CSF viral genome amplification and IFN-alpha measurement are informative and could be useful to confirm the viral origin of various neurological disorders, although the sensitivity and specificity of IFN-alpha measurement for the diagnosis of viral infection need further confirmation.  相似文献   
42.
The aim of this work was to identify Lactobacillus johnsonii NCC533 (La1) surface molecules mediating attachment to intestinal epithelial cells and mucins. Incubation of Caco-2 intestinal epithelial cells with an L. johnsonii La1 cell wall extract led to the recognition of elongation factor Tu (EF-Tu) as a novel La1 adhesin-like factor. The presence of EF-Tu at the surface of La1 was confirmed by analysis of purified outer surface protein extract by immunoblotting experiments, by electron microscopy, and by enzyme-linked immunosorbent assays of live bacteria. Furthermore, tandem mass spectrometry analysis proved that EF-TU was expressed at the La1 surface as an intact molecule. Using recombinant La1 EF-Tu protein, we were able to determine that its binding to intestinal cells and to mucins is pH dependent. Competition experiments suggested that EF-Tu has an important role in La1 mucin binding capacity. In addition, immunomodulation studies performed on HT29 cells showed that EF-Tu recombinant protein can induce a proinflammatory response in the presence of soluble CD14. Our in vitro results indicate that EF-Tu, through its binding to the intestinal mucosa, might participate in gut homeostasis.  相似文献   
43.
The infectious power of Pneumocystis carinii f. sp. hominis was explored by inoculating SCID mice intranasally with either P. carinii f. sp. hominis or P. carinii f. sp. muris isolates. Only mice inoculated with mouse parasites developed Pneumocystis pneumonia, as assessed by microscopy and PCR. These results suggest that humans do not contract pneumocystosis from animals.  相似文献   
44.
Neu-Laxova Syndrome (NLS) is a severe disorder with intrauterine growth retardation, edema, and characteristic face (including microcephaly with receding forehead, protuberant eyes, a flattened nose, deformed ears, cleft palate, and micrognathia). Ichthyosis is often present. Limb anomalies include hypoplastic fingers and syndactyly of fingers and toes. Patients are usually stillborn or die shortly after birth. We report five unrelated patients--four with atypical NLS and one with typical NLS. All five patients were stillbirths. Clinically, the atypical NLS patients showed a large skull; rhizo-, meso-, and acromelia; and hypoplasia of the metacarpals and phalanges. The feet were similarly affected. Radiographically, the atypical patients showed interpediculate narrowing and hypoplastic vertebral bodies. The long bones were stick-like, showing diaphyseal widening that spared the metaphyses and was more pronounced in the lower extremities. The ilia had a half-moon configuration with widening of the sacrosciatic notches. The ischia were vertical and the pubic bone was absent. The typical NLS patient showed microcephaly, normal vertebral body, and long bone ossification, but a pelvic configuration similar to that of the atypical NLS patients. The common and distinguishing clinical and radiographic features are reviewed. Scott et al. [1981: Am J Med Genet 9:165-175] described two patients with NLS with radiographic and clinical findings similar to patients 1-4 reported here. Patients 1-4 of this report lack the typical findings of NLS and likely represent a distinct lethal skeletal dysplasia.  相似文献   
45.
Compilation of published comparative genomic hybridization studies   总被引:6,自引:0,他引:6  
The power of comparative genomic hybridization (CGH) has been clearly proven since the first paper appeared in 1992 as a tool to characterize chromosomal imbalances in neoplasias. This review summarizes the chromosomal imbalances detected by CGH in solid tumors and in hemopathies. In May of 2001, we took a census of 430 articles providing information on 11,984 cases of human solid tumors or hematologic malignancies. Comparative generic hybridization has detected a number of recurrent regions of amplification or deletion that allows for identification of new chromosomal loci (oncogenes, tumor suppressor genes, or other genes) involved in the development, progression, and clonal evolution of tumors. When CGH data from different studies are combined, a pattern of nonrandom genetic aberrations appears. As expected, some of these gains and losses are common to different types of pathologies, while others are more tumor-specific.  相似文献   
46.
47.
Cryptosporidium parvum is usually considered the agent of human cryptosporidiosis. However, only in the last few years, molecular biology-based methods have allowed the identification of Cryptosporidium species and genotypes, and only a few data are available from France. In the present work, we collected samples of whole feces from 57 patients from France (11 immunocompetent patients, 35 human immunodeficiency virus [HIV]-infected patients, 11 immunocompromised but non-HIV-infected patients) in whom Cryptosporidium oocysts were recognized by clinical laboratories. A fragment of the Cryptosporidium 18S rRNA gene encompassing the hypervariable region was amplified by PCR and sequenced. The results revealed that the majority of the patients were infected with cattle (29 of 57) or human (18 of 57) genotypes of Cryptosporidium parvum. However, a number of immunocompromised patients were infected with C. meleagridis (3 of 57), C. felis (6 of 57), or a new genotype of C. muris (1 of 57). This is the first report of the last three species of Cryptosporidium in humans in France. These results indicate that immunocompromised individuals are susceptible to a wide range of Cryptosporidium species and genotypes.  相似文献   
48.
We compared the QUANTIPLEX HIV-1 RNA 2.0 assay with the AMPLICOR HIV-1 MONITOR 1.0 assay for quantitation of human immunodeficiency virus type 1 (HIV-1) RNA in plasma in the Stadi trail, which evaluated a stavudine plus didanosine combination therapy in 52 patients. HIV-1 RNA baseline values measured with AMPLICOR HIV-1 MONITOR 1.0 were significantly higher than those measured with QUANTIPLEX HIV-1 RNA 2.0, and decreases in HIV-1 RNA levels from baseline were also found to be significantly higher when measured with the AMPLICOR HIV-1 MONITOR 1.0 assay. The frequency of HIV-1 RNA levels below the lower limit of quantitation was significantly higher with QUANTIPLEX HIV-1 RNA 2.0 than with AMPLICOR HIV-1 MONITOR 1.0. Reanalysis of these results by an ultrasensitive procedure of AMPLICOR HIV-1 MONITOR 1.0 or by a modified version of the test that included additional primers adapted for non-B HIV-1 clades yielded greater differences between the QUANTIPLEX HIV-1 RNA 2.0 assay and the AMPLICOR HIV-1 MONITOR 1.0 assay. Our results indicate that a valid comparison of the virological efficacies obtained with different antiretroviral drug regimens requires the use of the same viral load quantitation procedure; further standardization between the different HIV-1 RNA quantitation kits is therefore needed.  相似文献   
49.
The association between bone mass, body structure, and body composition was explored in 156 men, 40 years of AGE . Bone mineral density (total body, lumbar spine, left arm, and left leg) was obtained by dual‐energy X‐ray absorptiometry (DXA; Hologic QDR 4500A). Body structure was determined from a battery of anthropometric dimensions with a principal components analysis. Body composition was estimated with DXA. From the 24 anthropometric dimensions, three components were extracted and identified as muscle, fat, and skeletal length. Significant correlations between the muscle component and all BMD measurements (r = 0.28–0.44) were obtained. Except for BMD of the left arm, which correlated significantly, but negatively, with the fat component (r = ?0.16), no significant relations were found between the fat component and BMD. There were significant correlations between lean mass, fat mass, and BMD measurements. The correlations were higher between lean mass and BMD (r = 0.22–0.44) than between fat mass and BMD (r = 0.08–0.24). The multiple regression analysis revealed that except for BMD of the left arm only lean mass or the muscle component, and not fat mass or the fat component, were independent predictors of BMD. It is concluded that the principal anthropometric determinant of BMD in middle‐aged men is lean mass or muscle. Am. J. Hum. Biol. 14:735–742, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
50.
When cells are infected with viruses, they may trigger their apoptosis programs. In unicellular organisms, this may have protected cell populations by limiting viral replication from infected cells. Multicellular organisms can also trigger the apoptosis program after viral infection. In response, viruses have evolved a wide variety of inhibitors of apoptosis. In higher organisms, the outcome of viral infections is largely determined by the immune system. Since apoptosis is intimately linked to the function and regulation of the immune system, the ability of viruses to inhibit apoptosis could profoundly alter the immune response. Viral antiapoptotic proteins could protect infected cells from apoptosis induced by cytotoxic lymphocytes, alter antigen cross-presentation and the priming of the immune response, or modulate the expression of danger signals from sites of infection. The virus/host interaction is likely to provide useful lessons regarding the workings of the mammalian immune system.  相似文献   
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