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991.
992.
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994.

Aim

Evaluate the effects of smoking on dendritic cells (DCs), cytokines, clinical periodontal parameters, and number of teeth in samples of human chronic periodontitis (CP).

Material and methods

Gingival samples were obtained from 24 smokers and 21 non-smokers with CP. Periodontal examination was carried out. Immunohistochemical staining was performed to identify Factor XIIIa+ immature, CD1a+ immature, and CD83+ mature DCs. The inflammatory infiltrate was counted, and IL-2, IL-10, IL-4, IL-6, IFN-γ, TNF-α, and IL-17A were measured using the cytometric bead array (CBA). Inflammatory infiltrate, DCs, cytokines, classification of CP, clinical periodontal parameters, number of teeth, smoking habit in years (SH/years), and number of cigarettes smoked per day (C/day) were correlated and compared.

Results

CD83+ mature DCs decreased in the smokers group. Negative correlations could be observed between the number of C/day with levels of IL-17A and number of teeth. Correlations between smoking, periodontal disease status, and other cytokines were not observed.

Conclusions

Smoking decreases mature DCs in chronic periodontitis. Moreover, a dose-dependent relation can be observed between C/day and number of teeth and levels of IL17A observed. Smokers show a different modulation of the CP immune response.  相似文献   
995.
The human leukocyte antigen G (HLA-G) is a non-classical HLA class I molecule predominantly expressed in trophoblastic placental cells to protect the fetus during pregnancy. However, evidence has shown that this molecule may be implicated in the immune escape mechanism of tumor cells. Thus, the aim of this study was to evaluate the frequency of 14-bp insertion/deletion HLA-G polymorphism, as well as the expression of this molecule in patients with invasive breast ductal carcinoma (IDC). A significant association between the expression of HLA-G and the presence of metastasis in lymph nodes (p = 0.01) was observed and the expression of HLA-G was significantly higher in patients with shorter survival time (p = 0.03). The analysis suggests that the polymorphism observed in patients with IDC may be inducing a higher expression of the HLA-G molecule, which may possibly contribute to shorter survival time and a worse clinical prognosis for such patients.  相似文献   
996.
Tumor establishment, growth, and survival are supported by interactions with microenvironment components. Here, we investigated whether the interactions between prostate cancer cells and cortical astrocytes are associated to a potential role for astrocytes in tumor establishment. We demonstrate that astrocytes interact in vitro with prostatic cancers cells derived from different metastatic sites. Astrocytes and their secreted extracellular matrix, stimulate DU145 cell (a brain-derived prostate tumor cell line) proliferation while inhibiting cell death and modulating the expression of several genes related to prostate cancer progression, suggesting the activation of EMT process in these cells. In contrast, DU145 cells and their conditioned medium inhibited cell proliferation and induced cell death of astrocytes. On the other hand, the astrocytes were unable to significantly induce an increment of LNCaP cell (a lymph node-derived prostate tumor cell line) proliferative activity. In addition, LNCaP cells were also unable to induce cell death of astrocytes. Thus, we believe that DU145 cells, but not LNCaP cells, present an even more aggressive behavior when interacting with astrocytes. These results provide an important contribution to the elucidation of the cellular mechanisms involved in the brain microenvironment colonization.  相似文献   
997.
Background: Chronotype, phase preference to perform activities during a 24-hour day, represents distinct circadian temporal organization of living organisms. Morning and evening types can be identified by questionnaires such as Horne and Östberg (HO) and Munich Chronotype Questionnaire (MCTQ). Environmental factors, such as different light–dark cycles experienced at different latitudes, interact with the organisms’ circadian timekeeping system. Therefore, chronotype is expected to vary as a result of different geographical locations.

Aim: To identify differences in chronotype distribution in populations of two Brazilian cities, Natal and Sao Paulo, located at different latitudes.

Subjects and methods: Two specific questionnaires, the Horne and Östberg Questionnaire (HO) and the Munich Chronotype Questionnaire (MCTQ), were used to identify chronotypes of undergraduate students from São Paulo and Natal.

Results: The comparison of the curve distributions of HO and MCTQ scores between both cities allowed one to observe that, while HO curves of São Paulo and Natal overlapped, MCTQ curves showed a clear shift towards eveningness in São Paulo.

Conclusion: This experiment confirmed results from previous studies that the farther away from the equator, the longer the delay of the sleep phase. It was also concluded that MCTQ is better at detecting this phenomenon.  相似文献   

998.
Aim: The purposes of this study were: (i) to identify familial resemblances in body fat, blood pressure (BP) and total physical activity (TPA); (ii) to estimate the magnitude of their genetic and environmental influences; and (iii) to investigate shared familial aggregation among these phenotypes.

Subjects and methods: The sample comprised 260 nuclear families from Portugal. Body fat was assessed by bioelectrical impedance. BP was measured by an oscillometric device. TPA was estimated by the Baecke questionnaire. Familial correlation analyses were performed using Generalized Estimating Equations. Quantitative genetic modelling was used to estimate maximal heritability, genetic and environmental correlations.

Results: Familial intra-trait correlations ranged from 0.15–0.38. Genetic and common environmental factors explained from 30%--44% of fat mass depots and BP and 24% of TPA. Genetic correlations were significant between BP and the fat mass traits (p?p?Conclusions: The results suggest familial resemblance in the variation of body fat, BP and TPA, showing partial pleiotropic effects in the variation in body fat phenotypes and BP. TPA only shares common environmental influences with BP and body fat traits.  相似文献   
999.

Purpose

Regulatory T cells are involved in the clinical course of chronic Chagas disease, possibly because they exercise a control in the patient’s inflammatory response to Trypanosoma cruzi. This study analyzed the levels of CD4?+?CD25+ T cells in chronic Chagas disease patients after in vitro stimulation of the peripheral blood mononuclear cells with CRA (Cytoplasmic Repetitive Antigen) or FRA (Flagellar Repetitive Antigen) T. cruzi antigens.

Methods

Groups of patients with the cardiac form and indeterminate form; and non-infected individuals, were selected. The CD4?+?CD25+ T lymphocyte population, as well as the FoxP3 expression and the IL10 production, were evaluated by flow cytometry after stimulation with CRA or FRA.

Result

The IND group presented higher levels of CD4?+?CD25+ T cells than the CARD group. However, there was no evidence of a relationship between FoxP3 and IL10 with any of the chronic forms.

Conclusions

Our results suggest the possible involvement of CD4?+?CD25+ T cells specific to CRA and FRA in controlling the progression of clinical outcomes. Though, further studies are needed to define which mechanisms activate regulatory T cells and lead to pathology control in chronic human Chagas disease.  相似文献   
1000.
Primary immunodeficiencies are intrinsic defects in the immune system that result in a predisposition to infection and are frequently accompanied by a propensity to autoimmunity and/or immunedysregulation. Primary immunodeficiencies can be divided into innate immunodeficiencies, phagocytic deficiencies, complement deficiencies, disorders of T cells and B cells (combined immunodeficiencies), antibody deficiencies and immunodeficiencies associated with syndromes. Diseases of immune dysregulation and autoinflammatory disorder are many times also included although the immunodeficiency in these disorders are often secondary to the autoimmunity or immune dysregulation and/or secondary immunosuppression used to control these disorders. Congenital primary immunodeficiencies typically manifest early in life although delayed onset are increasingly recognized. The early diagnosis of congenital immunodeficiencies is essential for optimal management and improved outcomes. In this International Consensus (ICON) document, we provide the salient features of the most common congenital immunodeficiencies.  相似文献   
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