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71.
Introduction  Asthma is one of the most common respiratory diseases caused by acute and chronic inflammation of airways. Proinflammatory cytokines could contribute to this inflammatory process. This study was performed in order to analyze the genetic profile of proinflammatory cytokines in Iranian asthmatic patients. Patients and Methods  The allele and genotype frequencies of a number polymorphic genes coding for tumor necrosis factor (TNF)-α, interleukin (IL)-1α, IL-1β, IL-1 receptor (IL-1R), IL-1RA, and IL-6 were investigated in 60 patients with asthma in comparison with 140 controls using polymerase chain reaction with sequence-specific primers. Results  The most frequent genotypes in our patients were TNF-α GA at position −308 (P = 0.001), TNF-α AA at position −238 (P = 0.01), IL-1α TC at position −889 (P = 0.0001), IL-1β TC at position −511 (P = 0.0001), and IL-1RA TC at position Mspa-I 11100 (P = 0.001). In contrast, the frequencies of the genotypes TNF-α GG at position −308 (P = 0.001), IL-1α CC at position −889 (P = 0.005), IL-1β CC at position −511 (P = 0.0001), and IL-1RA TT at position Mspa-I 11100 (P = 0.0001) in the patient group were significantly lower than controls. The most frequent haplotypes for TNF-α (positions 308, −238) was A/A in the patient group in comparison with controls (P = 0.0001). Conclusion  While environmental factors are important in the development of asthma, genetic factors could have a critical role in the expression of the disease. Considering the high frequency of presence of TNF-α AG genotype (−308), it seems that the production of TNF-α in the asthmatic patients could be higher than normal subjects.  相似文献   
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Periodontal disease involves complex interactions of microorganisms and host defenses. This work investigated the associations between putative bacterial pathogens, herpesviruses and chronic periodontitis. Subgingival samples were collected from 40 periodontally healthy individuals and from 40 patients with chronic periodontitis with probing depths of ≤3 mm or ≥6 mm. Multiplex and nested polymerase chain reactions were used to identify bacterial pathogens and herpesviruses. Porphyromonas gingivalis, Tannerella forsythia, Epstein–Barr virus (EBV) type 1, cytomegalovirus (CMV), Aggregatibacter actinomycetemcomitans and EBV type 2 were detected in, respectively, 95, 75, 72.5, 50, 12.5 and 10% of sites with probing depths ≥6 mm. P. gingivalis, T. forsythia, EBV‐1 and CMV were statistically associated with probing depths ≥6 mm. A. actinomycetemcomitans and EBV‐2 showed no association with periodontitis sites, and no significant associations were found for any of the test infectious agents and probing depths ≤3 mm. Our results confirm an association between P. gingivalis, T. forsythia, EBV‐1 and CMV, and chronic periodontitis. These infectious agents may play an important synergistic role in the pathogenesis of chronic periodontitis.  相似文献   
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OBJECTIVE: This study sought to investigate whether low-level laser therapy (LLLT) with a helium-neon (He-Ne) laser would affect mast cell number and degranulation in second-degree burns in rats. Background Data: LLLT has been recently applied to stimulate the wound healing process. MATERIALS AND METHODS: Sixty-five rats were randomly allocated to one of five groups. A deep second-degree burn was inflicted on all rats except those in the control group. In the sham-exposed group burns remained untreated. In the two laser-treated groups, the burns were irradiated every day by LLLT, with energy densities of 1.2 and 2.4 J/cm(2). In the fifth group the burns were treated topically with 0.2% nitrofurazone cream every day. The unburned skin of the rats in the control group were used for baseline study. The effects on mast cell number and degranulation were assessed by counting the number of intact and degranulated mast cells in sections fixed in formalin and stained with toluidine blue. RESULTS: On the seventh and 16th days post-burn, the type 1 mast cell count in the 2.4-J/cm(2) laser-treated group was significantly higher than that of the control group. On the 30th day, the total numbers of mast cells in the laser-treated groups were lower than those in the control and sham-exposed groups. CONCLUSION: LLLT of deep second-degree cutaneous burns in rats significantly increased the number of intact mast cells during the inflammatory and proliferative phases of healing, and decreased the total number of mast cells during the remodeling phase.  相似文献   
74.
OBJECTIVE: This study explored the effects of low-level laser therapy (LLLT) on cellular changes in cell culture and organ culture of skin from streptozotocin-diabetic (STZ-D) rats. BACKGROUND DATA: Growth of skin and its fibroblasts are impaired in diabetes. Therefore the healing of skin wounds is impaired in diabetic patients. The positive effects of LLLT on complications of diabetes in patients and animal models have been shown. METHODS: Diabetes was induced in rats by streptozotocin 30 days after its injection. Two sets of skin samples were extracted from skin under sterile conditions. Fibroblasts that were extruded from the samples were proliferated in vitro, and another set of samples were cultured as organ culture. A 24-well culture medium containing Dulbecco's modified minimum essential medium was supplemented by 12% fetal bovine serum. There were five laser-treated and five sham-exposed groups. A helium-neon laser was used, and 0.9-4 J/cm(2) energy densities were applied four times to each organ culture and cell culture. The organ cultures were analyzed by light microscopy and transmission electron microscopy examinations. Cell proliferation was evaluated by dimethylthiazol-diphenyltetrazolium bromide (MTT) assay. RESULTS: Statistical analysis revealed that 4-J/cm(2) irradiation significantly increases the fibroblast numbers compared to the sham-exposed cultures (p = 0.046). CONCLUSION: It is concluded that LLLT resulted in a significant increase of fibroblast proliferation of STZ-D rats in vitro.  相似文献   
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Journal of Neurology - To report the understanding and decision-making of neuroimmunologists and their treatment of patients with multiple sclerosis (MS) during the early stages of the SARS-CoV-2...  相似文献   
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