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41.
Stroke affects primarily aged and co-morbid people, aspects not properly considered to date. Since angiogenesis/vasculogenesis are key processes for stroke recovery, we purposed to determine how different co-morbidities affect the outcome and angiogenesis/vasculogenesis, using a rodent model of metabolic syndrome, and by dynamic enhanced-contrast imaging (DCE-MRI) to assess its non-invasive potential to determine these processes. Twenty/twenty-two month-old corpulent (JCR:LA-Cp/Cp), a model of metabolic syndrome and lean rats were used. After inducing the experimental ischemia by transient MCAO, angiogenesis was analyzed by histology, vasculogenesis by determination of endothelial progenitor cells in peripheral blood by flow cytometry and evaluating their pro-angiogenic properties in culture and the vascular function by DCE-MRI at 3, 7 and 28 days after tMCAO. Our results show an increased infarct volume, BBB damage and an impaired outcome in corpulent rats compared with their lean counterparts. Corpulent rats also displayed worse post-stroke angiogenesis/vasculogenesis, outcome that translated in an impaired vascular function determined by DCE-MRI. These data confirm that outcome and angiogenesis/vasculogenesis induced by stroke in old rats are negatively affected by the co-morbidities present in the corpulent genotype and also that DCE-MRI might be a technique useful for the non-invasive evaluation of vascular function and angiogenesis processes.  相似文献   
42.
Phase-derived parameters and time autocorrelation functions were used to analyze the behavior of murine B16 cells exposed to different amplitudes of electroporation pulses. Cells were observed using an off-axis digital holographic microscope equipped with a fast camera. Series of quantitative phase images of cells were reconstructed and further processed using MATLAB codes. Projected area, dry mass density, and entropy proved to be predictors for permeabilized cells that swell or collapse. Autocorrelation functions of phase fluctuations in different regions of the cell showed a good correlation with the local effectiveness of permeabilization.  相似文献   
43.
The prevalence of obesity-related diabetes is increasing worldwide. Here we report the identification of a pentapeptide, GLP-1(32-36)amide (LVKGRamide), derived from the glucoincretin hormone GLP-1, that increases basal energy expenditure and curtails the development of obesity, insulin resistance, diabetes, and hepatic steatosis in diet-induced obese mice. The pentapeptide inhibited weight gain, reduced fat mass without change in energy intake, and increased basal energy expenditure independent of physical activity. Analyses of tissues from peptide-treated mice reveal increased expression of UCP-1 and UCP-3 in brown adipose tissue and increased UCP-3 and inhibition of acetyl-CoA carboxylase in skeletal muscle, findings consistent with increased fatty acid oxidation and thermogenesis. In palmitate-treated C2C12 skeletal myotubes, GLP-1(32-36)amide activated AMPK and inhibited acetyl-CoA carboxylase, suggesting activation of fat metabolism in response to energy depletion. By mass spectroscopy, the pentapeptide is rapidly formed from GLP-1(9-36)amide, the major form of GLP-1 in the circulation of mice. These findings suggest that the reported insulin-like actions of GLP-1 receptor agonists that occur independently of the GLP-1 receptor might be mediated by the pentapeptide, and the previously reported nonapeptide (FIAWLVKGRamide). We propose that by increasing basal energy expenditure, GLP-1(32-36)amide might be a useful treatment for human obesity and associated metabolic disorders.  相似文献   
44.
Leptin exists in a free form and a receptor-bound form. Protein-bound rather than free leptin levels may be associated with regulation of muscle sympathetic nerve activity (MSNA). We determined MSNA and bound leptin concentrations in 25 men [age, 29 +/- 6 yr, body mass index (BMI), 24 +/- 3 kg/m(2)]. Baroreflex sensitivity was measured using phenylephrine and nitroprusside infusions. We measured bound leptin in patients with central (multiple system atrophy, n = 8; age, 59 +/- 8 yr; BMI, 23 +/- 2 kg/m(2)) and peripheral autonomic failure (pure autonomic failure, n = 4; age, 71 +/- 10 yr; BMI, 25 +/- 3 kg/m(2)). MSNA was correlated with protein-bound leptin concentrations (r(2) = 0.35; P < 0.01) but not with free leptin levels (r(2) = 0.09). MSNA at baseline was 15 +/- 2 bursts x minutes(-1) in subjects with lower and 24 +/- 3 bursts x minutes(-1) in subjects with higher bound leptin concentrations (P < 0.05). Blood pressure as well as baroreflex regulation of heart rate and MSNA was similar in both groups. Phenylephrine and nitroprusside responses were similar. Patients with multiple system atrophy and autonomic failure featured similar bound leptin levels. We conclude that protein-bound rather than free leptin levels are correlated with basal sympathetic outflow in normotensive, nonobese men. This relationship cannot be explained by a direct central nervous effect of protein-bound leptin. Instead, protein-bound leptin may increase sympathetic vasomotor tone indirectly via a baroreflex mechanism.  相似文献   
45.
46.
CccDNA persistence during natural evolution of chronic VHB infection   总被引:4,自引:0,他引:4  
HBV infection remains a public health issue. CccDNA-HBV is a unique, intermediate replicative episome, responsible for persistence of infection in hepatocytes. The clearance of cccDNA may be explained by cellular death. CccDNA detection in chronic infected human livers may represent an important marker in monitoring antiviral therapy. Short term therapy is followed by viral rebound in the majority of chronic HBV hepatitis patients. Based on mathematical models, it is considered that the period needed to achieve a complete intrahepatic cccDNA clearance is 14.5 years.  相似文献   
47.
High molecular weight (HMW) and low molecular weight (LMW) forms of von Willebrand factor (vWF) were isolated from normal human plasma in the presence of protease inhibitors. HMW and LMW vWF preparations were subjected to reduction of interdimeric disulfide bridges under mild reducing conditions. Following sodium dodecyl sulfate electrophoresis in 3% agarose, the vWF bands were detected by immunoblotting with a polyclonal rabbit anti-vWF antiserum as well as with two monoclonal antibodies directed against epitopes located in the NH2-terminal (MAb 418) or in the COOH-terminal (MAb 9) region of the vWF subunit. Our results suggest that the slowest migrating band of the dimeric triplet set of LMW vWF represents an asymmetric structure composed of an intact subunit to which one NH2-terminal and one COOH-terminal fragment are linked by disulfide bridges. The intermediate band of the first triplet of LMW vWF strongly reacted with MAb 9 but not with MAb 418, indicating that it represents a dimer of COOH-terminal fragments. The fastest migrating band of the same triplet is apparently a dimer of the NH2-terminal fragments because it reacted with MAb 418 but not with MAb 9. Each next higher family of triplets seems to contain one more asymmetric fragment of dimeric size. These results are compatible with a model according to which LMW forms of vWF are derived from HMW vWF by proteolytic cleavage in the circulating blood.  相似文献   
48.
Micromanagement refers to a management style that involves managers exercising control over team members, teams, and also organizations, particularly in relation to the minutiae or minor details of day-to-day operations. While there is no single reason why some managers may choose to micromanage, many micromanagers exhibit similar behavioral traits, a consequence of perfectionism and/or underlying insecurities. In the culture of high performance that characterizes many contemporary mental health contexts, micromanagement also provides one way by which teams can be driven to achieve targets. However, over time, micromanagement leads to reductions in staff morale, creativity, and productivity; and increases in staff turnover. This paper provides an overview of micromanagement, including points of consideration for managers interested in reflecting on their management styles, and strategies for mental health nurses who find themselves working for a micromanager.  相似文献   
49.
We analysed the clinical history of 16 hemizygous males affected by Anderson‐Fabry Disease, from four families, to verify their intrafamilial phenotypic variability. Seven male patients, ranging from 26 to 61 years of age, died, whereas nine (age range 23–55) are alive. Eleven patients have undergone enzyme replacement therapy (ERT) for a period of 5–10 years. We have found a wide range of intrafamilial phenotypic variability in these families, both in terms of target‐organs and severity of the disease. Overall, our findings confirm previous data from the literature showing a high degree of intrafamilial phenotypic variability in patients carrying the same mutation. Furthermore, our results underscore the difficulty in giving accurate prognostic information to patients during genetic counselling, both in terms of rate of disease progression and involvement of different organs, when such prognosis is solely based on the patient's family history.  相似文献   
50.
The use of Doppler techniques, including power, colour and spectral Doppler, has greatly increased in rheumatology in recent years. This is due to the ability of Doppler US (DUS) to detect pathological vascularization within joints and periarticular soft tissues, thereby demonstrating the presence of active inflammation, which has been reported to be correlated with the local neo-angiogenesis. In synovitis, DUS showed a high correlation with histological and MRI findings, thus it is considered a valid tool to detect pathological synovial vascularization. Moreover, it is more sensitive than clinical examination in detecting active joint inflammation and in the evaluation of response to treatment. In addition, DUS may be considered as a reference imaging modality in the assessment of enthesitis, MRI being not sensitive and histology not feasible. Moreover, it has been demonstrated to be able to detect changes in asymptomatic enthesis. In conclusion, DUS is a useful and sensitive tool in the evaluation and monitoring of active inflammation. Its widespread use in clinical rheumatological practice is recommended. The aim of this article is to review the current literature about the role of DUS in rheumatic diseases, analysing its validity, reliability and feasibility.  相似文献   
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