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BACKGROUND: Systemic sclerosis (SSc) is a multisystem disease with underlying immune mechanisms. AIMS: To investigate the clinicopathological characteristics of the lesions; immunological alterations in the bronchoalveolar lavage fluid (BALF), peripheral blood, and skin; and correlations between the clinicopathological characteristics and immunological alterations in SSc. MATERIALS/METHODS: Skin biopsies, BALF, and peripheral blood samples were obtained from 19 patients (18 women, one man) with SSc and six age and sex matched healthy controls (HCs). Mononuclear inflammatory cells (MICs), CD4/CD8 cells, tumour necrosis factor alpha (TNFalpha), and interleukin 1beta (IL1-1beta) concentrations were examined in all samples using histological methods, enzyme linked immunosorbent assay, and immunoperoxidase staining. RESULTS: The mean (SD) age of the patients with SSc was 34.8 (2.6) years. Proteinuria, positive rheumatoid factor, and C reactive protein were seen in 15.8%, 26.3%, and 26.3% of patients, respectively. Compared with HCs, there were significantly higher: total MICs (macrophages, lymphocytes), neutrophils, and eosinophils in BALF, blood, and skin (all p<0.05); cytokine concentrations in BALF (TNFalpha, p<0.001; IL-1, p<0.01) and peripheral blood (p<0.01 and p<0.05); and CD8/CD4+ T cells in peripheral blood (p<0.05). Compared with HCs, lesional skin had significantly higher histiocyte cell counts (p<0.05), lower lymphocyte counts (p<0.05), and higher CD4/CD8 ratios (p<0.001). There were significant correlations between cytokine concentrations and CD8+ T cells and forced vital capacity (p<0.001 and p<0.01, respectively). CONCLUSIONS: MICs, CD4/CD8+ cells, and cytokines are altered in SSc. These alterations correlated with the underlying disease process and therefore may have pathogenic, modulatory, and potential prognostic roles in SSc.  相似文献   
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Toll-like receptors (TLR) have a key role in regulating immunity against microbial agents. Engagement of TLR by bacterial, viral or fungal components leads to the production and release of inflammatory cytokines. In this study we show that mainly TLR8 and also TLR7 act as the host sensors for human parechovirus 1, a single-stranded RNA (ssRNA) virus. Furthermore, we see that the viral ssRNA genome is detected in endosomal compartments by these TLR, which activate signalling that lead to the synthesis of pro-inflammatory molecules by the host.  相似文献   
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A convenient method for the preparation of imidazobenzimidazole3, imidazoimidazole5, imidazotriazole6 and pyrano [2, 3-c] oxazole7 derivatives is described. This depends on interaction of 2-methyl-4-arylidene-2-oxazolin-5-ones1 with o-diamines, thiosemicarbazide and/or ethylcyanoacetate. The effect of alcoholic potassium cyanide on oxazolinone1 was studied. Antibacterial activity of the obtained products was studied.  相似文献   
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An epizootic of Rift Valley fever in Egypt in 1997   总被引:4,自引:0,他引:4  
An epizootic of Rift Valley fever (RVF) occurred in Egypt between April and August 1997. The signs among infected cattle and sheep were high fever, icterus, bloody diarrhoea and abortion. Aborted sheep foetuses and sera from the affected herds were collected in the Aswan and Assiut Provinces, Upper Egypt, for virological and serological examination. A cytopathic effect was detected in Vero cell cultures 48 h after inoculation with the foetal liver and spleen suspensions. The same suspensions caused paralysis and mortalities two to three days post intracerebral injection in mice. The isolated virus was identified using an agar gel precipitation test (AGPT) and a direct fluorescent antibody technique. Serological examination revealed that all tested sheep (57) and cattle (93) gave positive results to serological tests, using a complement fixation (CF), serum neutralisation (SN) and indirect immunofluorescence assay; while only 48 (84.2%) out of 57 sheep sera and 69 (74.2%) out of 93 cattle sera gave positive results using an AGPT. Titration of the serum samples indicated that SN is more sensitive than CF. Importation of infected ruminants, especially camels from the Sudan, is the principal source of infection. Aswan, the nearest Egyptian province to the Sudan, is the focus of RVF virus infection in Egypt. As a result of high insect populations, the epizootics of RVF have usually occurred during the summer in Egypt. Reoccurrence of epizootics from time to time indicates failure of the applied RVF vaccination programme in Egypt.  相似文献   
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Microbial investigation of 30 samples of sausage meat and 30 samples of hamburger meat, freshly prepared, were collected randomly from different markets in Alexandria city, to determine the bacteriological status of these products. The average counts/gm of total bacteria, total coliforms and fecal coliform in sausage meat were 1.33 x 10(7), 9.16 x 10(5) and 1.11 x 10(3) respectively, and in hamburger samples were 8.47 x 10(5), 2.63 x 10(3) and 1.35 x 10(3) respectively. Shigella, Escherichia coli, Staphylococcus aureus and Proteus spp were isolated with various percentages, whereas Salmonella spp was isolated from sausage only. The public health importance of the isolated microorganisms are fully discussed.  相似文献   
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John Cunningham virus (JCV) encodes an oncogenic T‐antigen, which is capable of interacting with key growth regulatory pathways. JCV definite role as causal agent of human cancer, still awaits final confirmation. The present study was conducted to assess the possible role of JCV in Egyptian colorectal carcinoma (CRC) and correlate the expression with the clinicopathological features and survival. JCV in situ hybridization (ISH) signals and large T antigen immunoreactivity were examined in 87 colonic specimens. Positive glandular JCV ISH signals were detected in 20%, 25% and 40% of normal, adenoma and CRC cases respectively. Stromal JCV ISH signals were identified in 26% of CRC cases and 5% of adenoma however, normal mucosa did not show stromal positivity with significant difference (p = 0.03). Glandular JCV expression was significantly associated with high grade (p = 0.03), high mitotic index (p=0.02) and low apoptotic index (p = 0.00). Positive stromal signals were significantly associated with low apoptosis (p = 0.00). No positive nuclear immunostaining of JCV large T antigen was detected in all specimens. JCV stromal expression was the 2nd most powerful indicator of short survival and bad prognosis (p = 0.03) in CRC patients. JCV might play an etiological role in CRC tumorogenesis and short survival in Egyptian CRC patients.  相似文献   
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