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A regulatory single nucleotide polymorphism located in the 5′ region (?169T/C) of the Fc receptor-like 3 (FCRL3_3) gene has been associated with both susceptibility and protection in immune diseases. This case–control study aimed to evaluate the association between FCRL3 polymorphisms and juvenile rheumatoid arthritis (JRA), asthma, and childhood-onset systemic lupus erythematosus (SLE) in a Mexican population. We performed PCR-based genotyping to identify four FCRL3 single nucleotide polymorphisms (FCRL3_3 to FCRL3_6) in patients with JRA (n = 202), asthma (n = 239), or childhood-onset SLE (n = 377), and healthy controls (n = 400). The case–control analysis showed a male-gender dependent association between the FCRL3_3C, FCRL3_5C, and FCRL3_6A alleles and either JRA (OR = 0.57, p = 0.003; OR = 0.55, p = 0.002; OR = 0.53, p = 0.0007, respectively) or asthma (OR = 0.72, p = 0.04; OR = 0.74, p = 0.05; OR = 0.70, p = 0.02, respectively). As expected, minor alleles of these SNPs with the CGCA haplotype were also significantly associated with JRA (OR = 0.35, p = 0.00005) and asthma (OR = 0.61, p = 0.007). We found no association between FCRL3 SNPs or haplotypes and childhood-onset SLE. These results supported the notion that FCRL3 is involved in the etiology of several immune diseases. Our results also suggested that SNPs located in the FCRL3 gene were protective against JRA and asthma in male Mexican patients.  相似文献   
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Butyrate is produced in the colon of mammals as a result of microbial fermentation of dietary fiber, undigested starch, and proteins. Butyrate may be an important protective agent in colonic carcinogenesis. Trophic effects on normal colonocytesin vitro andin vivo are induced by butyrate. In contrast, butyrate arrests the growth of neoplastic colonocytes and inhibits the preneoplastic hyperproliferation induced by some tumor promotersin vitro. We speculate that selective effects on G-protein activation may explain this paradox of butyrate's effects in normal versus neoplastic colonocytes. Butyrate induces differentiation of colon cancer cell lines. It also regulates the expression of molecules involved in colonocyte growth and adhesion and inhibits the expression of several protooncogenes relevant to colorectal carcinogenesis. Additional studies are needed to evaluate butyrate's antineoplastic effectsin vivo and to understand its mechanism(s) of action.  相似文献   
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Background

Patients given allogeneic hematopoietic stem cell transplants (HSCT) may develop secondary malignant neoplasms (SMN). Several variables have been identified but there are no data about the incidence of this complication in individuals given HSCT using reduced-intensity conditioning (RIC) methods.

Objective

Define the incidence of SMN in patients given HSCT using a RIC preparative regimen conducted on an outpatient basis.

Materials and methods

Patients given HSCT in two institutions between October 1998 and 2012 were analyzed. To appraise the SMN appearance, those patients dead were also regarded as censored at that moment, as well as those lost to follow up and those alive at the closing of the study. 95% Confidence intervals (CI) for the survival or failure estimate were calculated with the Greenwood's method.

Results

A total of 416 allografted patients with a Karnofsky performance index of 100% were included in the study. All patients received peripheral blood stem cells allografts. The conditioning regimen was delivered as an outpatient procedure in all individuals. No patient was given radiotherapy nor antithymocyte globulin during the conditioning. Three hundred and sixty five patients (88%) were never admitted to the hospital, whereas 12% were admitted because of grade III–IV acute graft versus host disease (aGVHD), fever, or mucositis. Median survival time was 15.7 months. Survival at 6 months (95% CI): 66.4% (61.5–70.8%), at 12 months: 53.3% (48.1–58.1%), at 60 months: 30.6% (30.5–41.5%). Eight patients with a SMN were identified in the group of 416 allografted patients, SMN rates (95% CI) were: one year post graft: 1.9% (0.7–4.9%), 5 years: 3.8% (1.6–9.2%), 10 years: 6.8% (2.6–17.7%) and 13 years post-graft: 20.2% (5.5–59.2%), the cumulative probability of SMN being 6.8 at 10 years. Since the number of expected cases in the general population is 0.62, the ratio of observed to expected cases is 12.9 (P < 0.001). This figure means that the risk of developing a malignant neoplasm in allografted individuals using our method is 12.9 times higher than that in the general population. There were three non-Hodgkin's lymphomas, two M2 acute myelogenous leukemias, one hairy cell leukemia, one tongue epidermoid carcinoma, and one breast carcinoma.

Conclusions

We have found a low incidence of SMN in this group of Mexican patients allografted with the Mexican RIC method. Possible explanations for this difference are discussed, focusing on the RIC preparative regimen.  相似文献   

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The prevalence of endobronchial tuberculosis (EBTB) in patients with active tuberculosis is about 10% to 40%. The most common complication of EBTB is bronchial stenosis. Fistula formation by pulmonary tuberculosis is a very rare complication and is most commonly bronchopleural. The authors present a 53-year-old woman presented with chronic cough and abnormality in chest computed tomography scan. According to chest computed tomography scan finding, bronchoscopic study was done and bronchial lavage was obtained. Bronchial lavage was positive for acid fast bacilli. Bronchoscopy showed fistula formation between the right and left main bronchus, a rare manifestation of EBTB. The patient was treated with antituberculosis therapy, and her symptoms improved and radiological findings showed regression of pulmonary lesions.  相似文献   
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