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目的探讨家族性低镁血症高钙尿症和肾钙质沉着症(FHHNC)的临床特征和致病基因特点。方法分析1例2月龄FHHNC女性患儿的临床资料。结果患儿血镁低,尿钙高;肾脏超声提示肾髓质回声增强;多次尿培养大肠埃希菌。基因测序显示患儿CLDN16基因2处杂合变异c.324+1GC,c.317CT(p.Ser 106 Phe)。予抗感染及25%硫酸镁、门冬氨酸钾镁、10%枸橼酸钠口服治疗,病情好转。结论 FHHNC罕见且预后差,目前除肾移植外无特殊治疗方法,基因检测有助于早期诊断。  相似文献   
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The susceptibility and severity of periodontal diseases is made more severe by diabetes, with the impact on the disease process inversely proportional to the level of glycemic control. Although type 1 diabetes mellitus and type 2 diabetes mellitus have different etiologies, and their impact on bone is not identical, they share many of the same complications. Studies in animals and humans agree that both forms of diabetes increase inflammatory events in periodontal tissue, impair new bone formation, and increase expression of RANKL in response to bacterial challenge. High levels of glucose, reactive oxygen species, and advanced glycation end-products are found in the periodontium of diabetic individuals and lead to increased activation of nuclear factor-kappa B and expression of inflammatory cytokines such as tumor necrosis factor and interleukin-1. Studies in animals, moreover, suggest that there are multiple cell types in periodontal tissues that are affected by diabetes, including leukocytes, vascular cells, mesenchymal stem cells, periodontal ligament fibroblasts, osteoblasts, and osteocytes. The etiology of periodontal disease involves the host response to bacterial challenge that is affected by diabetes, which increases the expression of RANKL and reduces coupled bone formation. In addition, the inflammatory response also modifies the oral microbiota to render it more pathogenic, as demonstrated by increased inflammation and bone loss in animals where bacteria are transferred from diabetic donors to germ-free hosts compared with transfer from normoglycemic donors. This approach has the advantage of not relying upon limited knowledge of the specific bacterial taxa to determine pathogenicity, and examines the overall impact of the microbiota rather than the presumed pathogenicity of a few bacterial groups. Thus, animal studies have provided new insights into pathogenic mechanisms that identify cause-and-effect relationships that are difficult to perform in human studies.  相似文献   
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Bacterial outer membrane vesicles (OMVs) play a vital role in the mechanism of host―pathogen communication, while emerging evidence suggests that OMVs regulate host immune responses through differentially packaged small noncoding RNAs (sncRNAs) to target host mRNA function. Therefore, we identified differentially packaged sncRNAs in Helicobacter pylori OMVs and showed transfer of OMV sncRNAs to human gastric adenocarcinoma cells in this study. Our data revealed that sncRNAs (sR-2509025 and sR-989262) were enriched in OMVs, and reduced lipopolysaccharide or OMV-induced interleukin 8 (IL-8) secretion by cultured AGS cells. Collectively, these findings are consistent with the hypothesis that sncRNAs in H. pylori OMVs play a novel role in the mechanism of host―pathogen interaction, whereby H. pylori evades the host immune response.  相似文献   
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BackgroundSome patients with sarcoidosis experience worsening of pulmonary lesions. However, no biomarker has been identified that reflects pulmonary disease status in sarcoidosis. We investigated the usefulness of potential markers of pulmonary fibrosis in patients with sarcoidosis.MethodsPlasma matrix metalloproteinase 7 (MMP-7), CC-chemokine ligand 18 (CCL-18), and periostin levels were evaluated in 60 patients with sarcoidosis and 30 healthy controls; bronchoalveolar lavage fluid levels were analyzed in 22 patients with sarcoidosis. To determine the usefulness of these markers, we explored potential correlations between these markers and sarcoidosis clinical characteristics.ResultsPlasma MMP-7, CCL-18, and periostin concentrations were significantly higher in patients with sarcoidosis than those in healthy controls. MMP-7 concentrations in plasma and bronchoalveolar lavage fluid were higher in patients with sarcoidosis with parenchymal infiltration than in those without lung lesions. Moreover, MMP-7 concentration was negatively correlated with pulmonary function.ConclusionAmong these novel biomarkers, MMP-7 most precisely reflected pulmonary sarcoidosis disease status and thus, might be useful for diagnosing and evaluating sarcoidosis, particularly in patients with pulmonary parenchymal lesions.  相似文献   
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