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21.
Reduced migratory function of circulating angiogenic progenitor cells (CPCs) has been associated with impaired neovascularization in patients with cardiovascular disease (CVD). Previous findings underline the role of the kallikrein-kinin system in angiogenesis. We now demonstrate the involvement of the kinin B2 receptor (B(2)R) in the recruitment of CPCs to sites of ischemia and in their proangiogenic action. In healthy subjects, B(2)R was abundantly present on CD133(+) and CD34(+) CPCs as well as cultured endothelial progenitor cells (EPCs) derived from blood mononuclear cells (MNCs), whereas kinin B1 receptor expression was barely detectable. In transwell migration assays, bradykinin (BK) exerts a potent chemoattractant activity on CD133(+) and CD34(+) CPCs and EPCs via a B(2)R/phosphoinositide 3-kinase/eNOS-mediated mechanism. Migration toward BK was able to attract an MNC subpopulation enriched in CPCs with in vitro proangiogenic activity, as assessed by Matrigel assay. CPCs from cardiovascular disease patients showed low B(2)R levels and decreased migratory capacity toward BK. When injected systemically into wild-type mice with unilateral limb ischemia, bone marrow MNCs from syngenic B(2)R-deficient mice resulted in reduced homing of sca-1(+) and cKit(+)flk1(+) progenitors to ischemic muscles, impaired reparative neovascularization, and delayed perfusion recovery as compared with wild-type MNCs. Similarly, blockade of the B(2)R by systemic administration of icatibant prevented the beneficial effect of bone marrow MNC transplantation. BK-induced migration represents a novel mechanism mediating homing of circulating angiogenic progenitors. Reduction of BK sensitivity in progenitor cells from cardiovascular disease patients might contribute to impaired neovascularization after ischemic complications.  相似文献   
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BackgroundThis study compares two latest-generation self-expanding transcatheter heart valves (THV), the supra-annular ACURATE neo (Boston Scientific) and the intra-annular Centera THV (Edwards Lifesciences).MethodsIn this single center observational cohort trial 317 patients treated with the ACURATE neo and 78 patients treated with the Centera TVH were included. The main endpoints were device success and the early safety endpoint at 30 days.ResultsBesides higher incidence of diabetes mellitus and higher body mass index in patients treated with the ACURATE neo THV, there were no baseline differences between the groups. Device success was similar in both groups (neo: 91.8% vs. Centera: 93.6%; P=0.598), with numerically higher rates of moderate to severe paravalvular leakage in the ACURATE neo group (4.7% vs. 1.3%; P=0.214). At 30 days all-cause mortality rates were low in both groups (0.3% vs. 0%; P=0.620) and no difference occurred in the early safety at 30 days (19.3% vs. 16.7%; P=0.599). However, all-cause stroke rates were significantly higher in patients treated with the Centera THV (6.4 vs. 1.6%; P=0.015).ConclusionsThe ACURATE neo and the Centera THV show low mortality rates as well as comparable, favorable hemodynamics. The finding of higher stroke rates at 30 days with the repositionable Centera SE-THV needs further assessment.  相似文献   
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Background

In this study, we evaluate a new bioadhesive for intra-abdominal onlay mesh fixation of a polypropylene–polyvinylchloride graft.

Methods

Three pieces of a commercially available polypropylene/polyvinylfluoride mesh, each 3 × 3 cm in size, and three pieces of the same mesh coated with a polysaccharide bioadhesive were fixated to the surface of the anterior abdominal wall of 30 New Zealand white rabbits. The fixation was performed either by using four transabdominal Prolene® 4/0 sutures, four spiral tacks (Protack 5 mm Tyco), or cyanoacrylate glue (Glubran® GEM, Viareggio, Italy). Each mesh position and the according kind of fixation were randomized before implantation. The animals were sacrificed 12 weeks postoperatively. After determining the extent of intra-abdominal adhesions, the meshes were excised en bloc with the anterior abdominal wall for tensile strength measurements and histological analysis.

Results

All meshes coated with the bioadhesive adhered to the intact peritoneum without extra fixation. Irrespective of the fixation technique coated meshes led to more and stronger adhesions. Mesh shrinkage by scarring was increased in coated meshes fixed with glue and low in uncoated meshes fixed with tacks. Testing the tensile strength, coated meshes fixed with transfascial sutures achieved the best results (16.14 ± 6.1 N), whereas coated meshes fixed with glue showed the lowest strength (10.39 ± 4.81 N). The foreign body reaction was considerably more distinctive using coated mesh. The mesh ingrowth was not influenced by this reaction.

Conclusions

All meshes coated with the new bioadhesive were self-adhesive in that way; they stayed in position when attached to the peritoneum. Although this may facilitate intra-operative mesh fixation, the bioadhesive displayed several disadvantages, such as stronger adhesions and an increased shrinkage of the implant. The tensile strength was not influenced by the use of the bioadhesive. At present, we see no major advantage for polysaccharide bioadhesive applied in this study.  相似文献   
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In this study we investigated 36 single nucleotide polymorphisms within 10 genes previously associated with major depression and bipolar disorder, as well as with the response to their treatment (ABCB1, ABCB4, TAP2, CLOCK, CPLX1, CPLX2, SYN2, NRG1, 5HTR1A and GPRIN2). No association with mood disorders and clinical outcomes was observed.  相似文献   
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Respiratory chain disorders (RCDs) have been included in the differential diagnosis of adult-onset leukodystrophies. Here, we first report a 32-year-old female with an atypical, adult-onset, non-syndromic RCD due to a mitochondrial DNA deletion and manifesting as complicated ataxia. A ‘leukodystrophic’ pattern was found on brain MRI, but it was neither isolated nor predominant because of the presence of overt basal ganglia and infratentorial lesions, which led us to the proper diagnosis. Subsequently, we evaluated our series of patients with RCDs in order to verify whether a ‘leukodystrophic’ pattern with little or no involvement of deep grey structures and brainstem may be found in adult-onset RCDs, as reported in children. Among 52 patients with adult-onset RCDs, no case with a ‘leukodystrophic’ pattern was found, apart from three cases with a classical phenotype of mitochondrial neurogastrointestinal encephalopathy. In addition, no case of RCDs was found among six cases of adult-onset leukodystrophy of unknown origin and at least one feature suggestive of mitochondrial disease. The review of the literature was in agreement with these findings. Thus, we provide evidence that, unlike in children, RCDs should not be included in the differential diagnosis of adult-onset leukodystrophies, except when there are additional MRI findings or clinical features which unequivocally point towards a mitochondrial disorder.  相似文献   
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Journal of Neurology - The current study examines the efficacy of speed of processing training (SOPT) to improve processing speed (PS) in individuals with multiple sclerosis (MS). Outcomes included...  相似文献   
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