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Aims

We explored the effect of remote ischaemic conditioning (RIC) on endothelial function and on circulating mediators.

Methods and results

In 20 healthy male volunteers (mean age 31?±?10 years), flow-mediated dilation (FMD) was measured before and after 20?min of arm ischaemia, followed by reperfusion. Remote ischaemic conditioning (RIC) was performed by applying 3 cycles of 5?min of ischaemia of the leg at the onset of index arm ischaemia. Each volunteer underwent the IR-induced vascular injury protocol with and without RIC in a crossover study design.In the control group, IR significantly reduced FMD (5.9?±?2.9% before IR vs. 2.2?±?3.7% after IR; p?<?0.001). This effect was significantly attenuated by performing RIC (FMD of 5.5?±?3.1% before IR vs. 4.0?±?3.4% % after IR; p for interaction?=?0.01). Serum levels of SOD and ADMA increased significantly whereas MCP-1 and VEGF levels decreased significantly.Only changes in SOD levels were significantly related to the degree of RIC induced protection (r²?=?0.34; p?=?0.018).

Conclusion

RIC has protective effects against endothelial IR injury. Our biomarker study suggests that anti-oxidative stress mediators, such as SOD, seem to be more involved in the pathogenesis of RIC-induced protection in humans than angiogenesis factors or chemo-attractant cytokines.  相似文献   
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Self peptides bound to HLA-DQ7 (α1*0501-β1*0301), one of the HLA molecules associated with protection against insulin-dependent diabetes mellitus, were characterized after their acid elution from immunoaffinity-purified HLA-DQ7 (α1*0501-β1*0301) molecules. The majority of these self peptides derived from membrane-associated proteins including HLA class I, class II, class II-associated invariant chain peptide and the transferrin-receptor (TfR). By in vitro binding assays, the specificity of these endogenous peptides for HLA-DQ7 (α1*0501-β1*0301) molecules was confirmed. Among these peptides, the binding specificity of the TfR 215 – 230 self peptide was further examined on a variety of HLA-DQ and DR dimers. Several findings emerged from this analysis: (1) this peptide displayed HLA-DQ allelic specificity, binding only to HLA-DQ7 (α1*0501-β1*0301); (2) when either the DQα or DQβ chain was exchanged, little or no binding was observed, indicating that specificity of HLA-DQ peptide binding was determined by polymorphic residues of both the α and β chains. (3) Unexpectedly, the TfR 215 – 230 self peptide, eluted from DQ, was promiscuous with regard to HLA-DR binding. This distinct DR and DQ binding pattern could reflect the structure of these two molecules as recently evidenced by crystallography.  相似文献   
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The aim of this study was to begin to parse the relative contributions of the right and left ventromedial prefrontal cortices (VMPC) in regard to social conduct, decision-making, and emotional processing. We hypothesized that the right VMPC is a critical component of the neural systems that subserve such functions, whereas the left VMPC is not. Seven participants with focal, stable unilateral lesions to the right (n = 4) or left (n = 3) VMPC were studied with procedures designed to measure social conduct, decision-making, and emotional processing and personality. The right-sided participants had profound disturbances of social and interpersonal behavior and of the ability to maintain gainful employment; they had defective performance and impaired anticipatory skin conductance responses during the Gambling Task; most had profound abnormalities of emotional processing and personality, and met criteria for "acquired sociopathy." By contrast, the left-sided participants had normal social and interpersonal behavior; they had stable employment; they performed normally and had normal skin conductance responses on the Gambling Task; they had normal emotional processing; and their personalities were unchanged from premorbid status. The marked deficits in social conduct, decision-making, and emotional processing in participants with unilateral right VMPC lesions are reminiscent in kind of those that have been reported in connection with bilateral VMPC lesions, albeit perhaps of lesser severity. The findings provide preliminary evidence that insofar as social, decision-making, and emotional functions are concerned, the right-sided component of the VMPC system may be critical, whereas the left-sided component may be less important.  相似文献   
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OBJECTIVE: The management of recent-onset rheumatoid arthritis (RA) is not well standardized. We conducted a survey of drugs prescribed to RA patients in Brittany at presentation and during the first 1 to 3 years of follow-up. METHODS: A cohort of 270 patients with recent-onset inflammatory joint disease was recruited between 1995 and 1997. The evaluation at presentation included a medical history, a thorough physical examination, and a standard battery of investigations. Follow-up at 6-month intervals was offered. At the last visit, between June and December 1999, a panel of five rheumatologists established that 98 patients had RA. RESULTS: At presentation, hydroxychloroquine and injectable gold were the most widely used second-line drugs, and only two patients were offered a combination of second-line drugs. At the last visit, the most commonly used drugs were methotrexate, injectable gold, and hydroxychloroquine (23, 23, and 21 patients, respectively); only three patients were on more than one second-line drug and 38 (38/98, 39%) patients were on glucocorticoid therapy. CONCLUSION: Rheumatologists in Brittany prefer monotherapy with hydroxychloroquine or injectable gold as the initial treatment. Later, they rely mainly on methotrexate, injectable gold, and hydroxychloroquine, often in combination with glucocorticoid therapy.  相似文献   
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Among the multifactorial causes of undernutrition in old age, gastrointestinal mucosa altered function and resulting specific malabsorption are the most relevant. Despite numerous studies that have dealt with the effects of aging on the digestive tract of mammals, results showed discrepancies in terms of proliferation and biochemical aging small intestine events. However, the slowing-down of the maturation process and the poor adaptation of metabolism and intestinal function are obvious and there is evidence that protective mechanisms are impaired with age and contribute to affecting the trophic activity and related systemic homeostasis. Good prospects to improve gastrointestinal function in the elderly are essential and research on nutritional intervention to limit and counteract age-related impairments must be extensive. Probiotics are good candidates and fermented milks might be of great interest. In the present study we first show the main structural and functional variations between 3- and 23-month-old rat small intestines. The trophic consequences of aging and nutritional adaptation under basal conditions are also analyzed and discussed after 20 days of a yogurt-supplemented specific diet in both young and aged rats. The main variations that occur with aging and yogurt diet are located in the proximal small intestine. The present findings indicate a slight improvement of morphological trophic parameters in both young and aged rats by yogurt, whereas enzymatic changes are more discrete. Despite the obvious age-related decrease in trophicity, we suggest that assessment of probiotic potentials on trophicity requires a more altered model than normal, healthy aging animals.  相似文献   
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