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In some patients, the inflation of balloons through the mitral orifice during percutaneous mitral valvuloplasties may impair intraventricular conduction. In some cases, this appears to correspond to a block of the anterior and middle network within the left branch of the bundle of His. This left "biblock" is characterized by extreme left axial deviation of AQRS, of about -60 to -70 degrees, with a QS aspect on D2 and D3, RS on V1 and R on V6 with no major prolongation of ventricular activation time. If this hypothesis is correct, it would support the "trifascicular" concept of the left branch of the bundle of His.  相似文献   
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Background:

This study tested the hypothesis that the low-grade inflammation presented in patients with bipolar disorder (BD) is associated with expansion of activated T cells, and this activated state may be due to a lack of peripheral regulatory cells.

Methods:

Specifically, we investigated the distribution of monocytes and lymphocyte subsets, and investigated Th1/Th2/Th17 cytokines in plasma by flow cytometry. Twenty-one BD type I patients and 21 age- and sex-matched controls were recruited for this study.

Results:

BD patients had increased proportions of monocytes (CD14+). Regarding lymphocyte populations, BD patients presented reduced proportions of T cells (CD3+) and cytotoxic T cells (CD3+CD8+). BD patients also exhibited a higher percentage of activated T CD4+CD25+ cells, and a lower percentage of IL-10 expressing Treg cells.

Conclusions:

Our data shed some light into the underlying mechanisms involved with the chronic low-grade inflammatory profile described in BD patients.  相似文献   
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Background

Since HLA-G is an immune checkpoint molecule and since Crohn’s disease (CD) and ulcerative colitis (UC) exhibit deregulated immune-mediated mechanisms, we aimed to evaluate intestinal HLA-G expression and soluble HLA-G (sHLA-G) levels in CD/UC patients stratified according to the CD phenotype/localization and UC extension.

Methods

HLA-G tissue expression was assessed by immunohistochemistry in biopsies collected from 151 patients (90 CD, 61 UC) and in surgical resection specimens (28 CD, 12 UC). Surgical material from 24 healthy controls was also assessed. Plasma sHLA-G levels (97 CD, 81 UC, and 120 controls) were evaluated using ELISA.

Results

HLA-G expression was similarly observed in the intestinal epithelial cells of control and CD/UC specimens. However, in biopsies, the plasma cells/lymphocytes infiltrating the lamina propria in CD/UC presented (1) increased HLA-G expression compared to controls (P?<?0.0001), (2) greater cell staining in UC cells than in CD cells irrespective of disease extent (P?=?0.0011), and (3) an increased number of infiltrating cells in the inflammatory CD phenotype compared to that in the stenosing and fistulizing phenotypes (P?=?0.0407). In surgical specimens, CD/UC patients exhibited higher infiltrating cell HLA-G expression in lesion areas than in margins. sHLA-G levels were higher in UC/CD patients (P?<?0.0001) than in controls, but no difference was observed between diseases.

Conclusions

Increased infiltrating cell HLA-G expression associated with increased sHLA-G levels in CD/UC patients may reflect ongoing host strategies to suppress chronic inflammation.

  相似文献   
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Objectives: To evaluate the possible relationship between aminotransferases levels and markers of oxidative stress in chronic hepatitis C patients. Design and methods: Patients without treatment for hepatitis were divided in to group I (15–39 U/L); group II (41–76 U/L) and group III (81–311 U/L) of activity alanine aminotransferase (ALT). Blood markers of oxidative stress [catalase (CAT), glutathione peroxidase (GPx), thiobarbituric acid‐reactive species (TBARS), nonprotein and protein thiol (NP‐SH and P‐SH) groups and vitamin C] were determined. Results: P‐SH and NP‐SH levels, TBARS, GPx and CAT were not different between groups. Vitamin C was significantly decreased in groups II (P=0.03) and III (P=0.001) when compared with group I and correlated negatively with aspartate aminotransferase (AST; r=?0.29, P=0.042). Conclusion: Vitamin C levels were negatively associated with AST, suggesting that vitamin C could be an additional indicator of hepatitis C severity.  相似文献   
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