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Helicobacter pylori was incriminated as an etiological factor of rosacea. However, there is still controversy about this association. We conducted a comparative study in order to assess the role of H. pylori in rosacea patients who had dyspeptic symptoms. The study included 68 patients and 54 controls. Screening for H. pylori was performed and positive cases were referred for gastric endoscopy. The inflammatory response and bacterial density were evaluated in gastric biopsy. H. pylori vacA alleles, cagA and iceA genotypes were assessed by polymerase chain reaction. We found that 49 rosacea (72%) and 25 controls (46.3%) were infected with H. pylori. Thirty‐one rosacea cases were papulopustular (PPR) while 18 were erythematotelangiectatic (ETR). Gastric ulceration was higher in PPR cases (38.7%) than ETR (11.1%) and controls (12%). A significant inflammatory reaction was observed more in PPR cases (74.2%) compared with 44.4% in ETR (P = 0.04) and 44% in controls (P = 0.02). Analysis of H. pylori genotypes revealed that vacA s1m1 was more identified in PPR cases (54.8%) compared with 22.2% in ETR (P = 0.03) and 16% in controls (P = 0.003). There was a significant elevation of cagA/vacA s1m1 positivity in PPR cases. After the eradication regimen of H. pylori, a significant improvement (P < 0.05) was observed in 15 out of 27 PPR cases (55.6%) compared with three out of 17 ETR (17.6%). We concluded that H. pylori has a significant role in rosacea patients who had dyspeptic symptoms. The PPR type is more influenced by H. pylori and this is regarded as being because of certain virulent strains that increase the inflammatory response in gastric mucosa and also in cutaneous lesions.  相似文献   
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Hepatitis C and brucellosis are infectious diseases that occur worldwide, and both are endemic in Egypt. Co-infection with both agents is possible, and this can involve the liver in various ways. In this study, we investigated serum tissue inhibitor metalloproteinase-1 (TIMP-1), viral load, and liver functions in patients co-infected with hepatitis C virus (HCV) before and after brucellosis treatment. Over 3 years, 241 consecutive HCV patients (before interferon therapy was received) with recurrent fever who had occupational contact with animals were tested for brucellosis co-infection by a standard tube agglutination test. In patients with dual infection, viraemia (RT-PCR), TIMP-1 measured by ELISA, and liver functions were assessed and re-evaluated 2 months after brucellosis treatment. The number of patients with HCV/brucellosis co-infection was 32 out of 241 (13.3%). TIMP-1, viraemia, AST, ALT and bilirubin showed significant decrease (improvement) after brucellosis treatment (p < 0.001) but an insignificant difference (p > 0.05) with regard to serum albumin and prothrombin concentration. The study revealed that brucellosis is an important infection in HCV-infected patients and can aggravate the course of disease, suggesting that early treatment and prevention are important.  相似文献   
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In a previous study, the musculoskeletal affections among kidney recipients (KR) were reported, with 63 KR suffering from joint affections. We sought to determine the prevalence of osteonecrosis (ON) among those KR with joint affections, its distribution among the affected joints, and possible risk predictors. KR were subjected to biochemical, haematological, and hepatitis serology estimations. Radiographic and magnetic resonance imaging were performed. Relevant data were retrieved from Patient Information System. Fourteen KR were suffering from ON, with an incidence of 22.2% in KR with joint affections and 12.0% in the target population of KR. The femoral head was affected in 57.1% and the femoral condyles in 28.6%. Hypocalcaemia was observed in KR with ON. Whether hypocalcaemia is a causative or associative of ON yet remains to be decided in forthcoming studies.  相似文献   
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The role of chromosomal inversions in speciation has long been of interest to evolutionists. Recent quantitative modeling has stimulated reconsideration of previous conceptual models for chromosomal speciation. Anopheles gambiae, the most important vector of human malaria, carries abundant chromosomal inversion polymorphism nonrandomly associated with ecotypes that mate assortatively. Here, we consider the potential role of paracentric inversions in promoting speciation in A. gambiae via "ecotypification," a term that refers to differentiation arising from local adaptation. In particular, we focus on the Bamako form, an ecotype characterized by low inversion polymorphism and fixation of an inversion, 2Rj, that is very rare or absent in all other forms of A. gambiae. The Bamako form has a restricted distribution by the upper Niger River and its tributaries that is associated with a distinctive type of larval habitat, laterite rock pools, hypothesized to be its optimal breeding site. We first present computer simulations to investigate whether the population dynamics of A. gambiae are consistent with chromosomal speciation by ecotypification. The models are parameterized using field observations on the various forms of A. gambiae that exist in Mali, West Africa. We then report on the distribution of larvae of this species collected from rock pools and more characteristic breeding sites nearby. Both the simulations and field observations support the thesis that speciation by ecotypification is occurring, or has occurred, prompting consideration of Bamako as an independent species.  相似文献   
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