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61.
Dermatomyositis (DM) is a connective tissue disease characterized by specific inflammatory lesions in muscle biopsy. It is caused by vasculitis determined by humoral factors with subsequent inflammatory cell accumulation, mainly T CD4+ and B cells, which infiltrate myocytes leading to its vacuolization and degeneration (mainly in the skeletal muscles, rarely in the smooth muscles). The incidence of DM is estimated at 1-10 per million in adults and at 1-3.2 per million in children. The autoimmune mechanism of disease induction is not fully recognized. Several lines of evidence showed the link between DM and neoplastic disease. The first report of dermatomyositis associated with stomach cancer, by Stertz, comes from 1916. In the same time, Kankeleit reported DM associated with breast cancer. Presumably, it is the result of immune reaction against antigens common for muscle and neoplastic cells or some paraneoplastic syndrome underlying mechanism. The report presents the case of a 52-year-old woman with DM (diagnosed according to the Bohan and Peter criteria) and with coexistent squamous lung cancer in situ. The left upper lobectomy was performed. No complications in postoperative period were observed. During more than 2 years of follow-up after the surgery, the patient remained in good condition, without DM symptoms, or cancer relapse. Considering that DM may be associated with lung cancer; extensive diagnostic work-up to exclude neoplastic lesions should be performed. Patients aged 40 years or more should be particularly screened.  相似文献   
62.

Objectives

This study sought to compare the diagnostic accuracy of visual and quantitative analyses of myocardial perfusion cardiovascular magnetic resonance against a reference standard of quantitative coronary angiography.

Background

Visual analysis of perfusion cardiovascular magnetic resonance studies for assessing myocardial perfusion has been shown to have high diagnostic accuracy for coronary artery disease. However, only a few small studies have assessed the diagnostic accuracy of quantitative myocardial perfusion.

Methods

This retrospective study included 128 patients randomly selected from the CE-MARC (Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease) study population such that the distribution of risk factors and disease status was proportionate to the full population. Visual analysis results of cardiovascular magnetic resonance perfusion images, by consensus of 2 expert readers, were taken from the original study reports. Quantitative myocardial blood flow estimates were obtained using Fermi-constrained deconvolution. The reference standard for myocardial ischemia was a quantitative coronary x-ray angiogram stenosis severity of ≥70% diameter in any coronary artery of >2 mm diameter, or ≥50% in the left main stem. Diagnostic performance was calculated using receiver-operating characteristic curve analysis.

Results

The area under the curve for visual analysis was 0.88 (95% confidence interval: 0.81 to 0.95) with a sensitivity of 81.0% (95% confidence interval: 69.1% to 92.8%) and specificity of 86.0% (95% confidence interval: 78.7% to 93.4%). For quantitative stress myocardial blood flow the area under the curve was 0.89 (95% confidence interval: 0.83 to 0.96) with a sensitivity of 87.5% (95% confidence interval: 77.3% to 97.7%) and specificity of 84.5% (95% confidence interval: 76.8% to 92.3%). There was no statistically significant difference between the diagnostic performance of quantitative and visual analyses (p = 0.72). Incorporating rest myocardial blood flow values to generate a myocardial perfusion reserve did not significantly increase the quantitative analysis area under the curve (p = 0.79).

Conclusions

Quantitative perfusion has a high diagnostic accuracy for detecting coronary artery disease but is not superior to visual analysis. The incorporation of rest perfusion imaging does not improve diagnostic accuracy in quantitative perfusion analysis.  相似文献   
63.
It is known that tetanus toxoid (TTd)-hyperimmunization induces increased titer of sera β2-glycoprotein I (β2GPI)-specific antibodies (Abs) in Balb/c mice. The concentrations of such induced anti-β2GPI Abs as well as their pathogenic potential are strongly influenced by the context of TTd application. β2GPI-specific immune response is established as a part of TTd-specific immune response by molecular mimicry mechanism due to structural homology between TTd and β2GPI. This finding is supported by the following facts: (1) cross-reactive Abs that recognize both TTd and β2GPI epitopes are present in Balb/c mice sera; (2) anti-TTd Abs secretion in splenic cultures is induced after β2GPI stimulation and vice versa. However, analyses of (1) IL-10 production following in vitro stimulation of immunized Balb/c mice splenocytes by TTd, β2GPI or glutaraldehyde-treated β2GPI and (2) specific impact of ConA and agonists of TLR2, TLR4, and TLR9 on anti-TTd and autoreactive Abs secretion strongly imply that these two branches of the TTd-induced immune response do not use identical cell populations and are regulated in a different way. Results presented in this paper describe that structural homology between foreign and self-antigens could focus mounted autoreactive immune response toward specific self-structure, but the context of antigen application, including a history of previous immune stimulations and adjuvants applied together with the antigen, are the main factors which determine the outcome of the induced immune response.  相似文献   
64.
During inflammatory processes, tissue environmental cues are influencing the immunoregulatory properties of tissue-resident mesenchymal stem/stromal cells (MSC). In this study, we elucidated one of the molecular and cellular responses of human MSC exposed to combinations of inflammatory cytokines. We showed that during multi-cytokine priming by TNF-α, IL-1β, and IFN-γ, IL-1β further augmented the well-established immunoregulatory activity induced by TNF-α/IFN-γ. On the molecular level, TNF-α and IL-1β enhanced the expression of IFN-γ receptor (IFN-γR) via NF 'kappa-light-chain-enhancer' of activated B-cells (NF-κΒ) signaling. In turn, enhanced responsiveness to IFN-γ stimulation activated STAT5 and p38-MAPK signaling. This molecular feedback resulted in an increased IL-8 release and augmented recruitment of polymorphonuclear granulocytes (PMN). Our study suggests the possibility that responses of MSC to multi-cytokine priming regimens may be exploited therapeutically to fine-tune inflammatory activity in tissues. This study elucidates molecular mechanisms underlying the immunological priming of mesenchymal stromal cells (MSC) and their interaction with neutrophils.  相似文献   
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Objective

The aim of this study is to observe the effects of dark chocolate on endothelial function after a series of successive apnea dives in non-thermoneutral water.

Methods

Twenty breath-hold divers were divided into two groups: a control group (8 males and 2 females) and a chocolate group (9 males and 1 female). The control group was asked to perform a series of dives to 20 m adding up to 20 min in the quiet diving pool of Conflans-Ste-Honorine (Paris, France), water temperature was 27 °C. The chocolate group performed the dives 1 h after ingestion of 30 g of dark chocolate. Flow-mediated dilatation (FMD), digital photoplethysmography, nitric oxide (NO), and peroxynitrite ONOO?) levels were measured before and after each series of breath-hold dives.

Results

A significant decrease in FMD was observed in the control group after the dives (95.28 ± 2.9 % of pre-dive values, p < 0.001) while it was increased in the chocolate group (104.1 ± 2.9 % of pre-dive values, p < 0.01). A decrease in the NO level was observed in the control group (86.76 ± 15.57 %, p < 0.05) whereas no difference was shown in the chocolate group (98.44 ± 31.86 %, p > 0.05). No differences in digital photoplethysmography and peroxynitrites were observed between before and after the dives.

Conclusion

Antioxidants contained in dark chocolate scavenge free radicals produced during breath-hold diving. Ingestion of 30 g of dark chocolate 1 h before the dive can thus prevent endothelial dysfunction which can be observed after a series of breath-hold dives.  相似文献   
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