199 research outputs found
Evaluating the Ability of Entrepreneurial and Effectiveness of the Education System on the Rise of it ,in Payame Noor University Students
One of the main goals of education is the development of skilled manpower . Due to the increasing population and demand for entering the universities and higher education institutions and also the economic problems, the issue of "entrepreneurs" is an important matter The aim of this paper is to evaluate the ability of entrepreneurial in Payame Noor university. It asked 450 students at this University in Tehran to answer the questionnaire with 0.86% Cronbach's alpha coefficient and Likert respond method. The results show that: There is a significant and meaningful relation between student 's Creativity and independence and their willingness to entrepreneurship; Risk taking in male students is more than female students; Internal locus of control and independence in female students were significantly higher than male students; Achievement motivation, Internal locus of control and independence in basic science and engineering students were significantly more than the students in the humanities and Creativity in unemployed students was more than Employed ones. Internal locus of control and achievement motivation in Students who passed the Entrepreneurship course was more than Students who don' t passed it ;and Educational activities were related to the development of the components of creativity and motivation
The effects of grape seed extract on glycemic control, serum lipoproteins, inflammation, and body weight: A systematic review and meta-analysis of randomized controlled trials
The aim of this systematic review and meta-analysis was to analyze the effects of grape seed extract (GSE) on glycemic control and serum lipoproteins, inflammation and body weight. Two independent authors systematically searched online databases including EMBASE, Scopus, PubMed, Cochrane Library, and Web of Science from inception until May 30, 2019. Cochrane Collaboration risk of bias tool was applied to assess the methodological quality of included trials. The heterogeneity among the included studies was assessed using Cochrane's Q test and I-square (I2) statistic. Data were pooled using a random-effects model and weighted mean difference (WMD) was considered as the overall effect size. Fifty trials were included in this meta-analysis. Pooling effect sizes from studies demonstrated a significant decrease in fasting plasma glucose (FPG) (WMD): �2.01; 95 confidence interval (CI): �3.14, �0.86), total cholesterol (TC; WMD: �6.03; 95 CI: �9.71, �2.35), low-density lipoprotein (LDL) cholesterol (WMD: �4.97; 95 CI: �8.37, �1.57), triglycerides (WMD: �6.55; 95 CI: �9.28, �3.83), and C-reactive protein (CRP) concentrations (WMD: �0.81; 95 CI: �1.25, �0.38) following GSE therapy. Grape seed did not influence HbA1c, HDL cholesterol levels, and anthropometric measurements. This meta-analysis demonstrated that GSE intake significantly reduced FPG, TC, LDL cholesterol, triglycerides, and CRP levels. © 2019 John Wiley & Sons, Ltd
Brachial Flow-Mediated Dilation and Incident Atrial Fibrillation The Multi-Ethnic Study of Atherosclerosis
Objective—It is unknown whether endothelial dysfunction precedes atrial fibrillation (AF) development. The objective of
this study was to examine the association of brachial flow-mediated dilation (FMD) with incident AF.
Approach and Results—A total of 2936 participants (mean age, 61±9.9 years; 50% women; 66% nonwhites) from the
Multi-Ethnic Study of Atherosclerosis with available ultrasound brachial FMD measurements who were free of baseline
AF were included in this analysis. Baseline (2000–2002) FMD was computed from the percentage difference (%FMD)
in brachial artery diameter and maximum diameter during measured vasodilator response. AF was ascertained from
hospitalization data including Medicare claims during a median follow-up of 8.5 years. Probability-weighted Cox
proportional-hazards regression was used to compute hazard ratios and 95% confidence intervals for the association
between FMD as a continuous variable (%FMD values per 1-SD increase) and incident AF. Incident AF was detected in
137 (4.7%) participants. Those with %FMD values below the sex-specific median value (median %FMD; men, 3.6%;
women, 4.2%; incidence rate per 1000 person-years, 7.3; 95% confidence interval, 5.9–9.0) were more likely to develop
AF than people whose %FMD values were above the median value (incidence rate per 1000 person-years, 4.5; 95%
confidence interval, 3.4–5.8; log-rank P=0.0043). In a multivariable Cox regression analysis, each 1-SD increase in
%FMD values (SD, 2.8%) was associated with less incident AF (hazard ratio, 0.84; 95% confidence interval, 0.70–0.99).
These results were consistent across subgroups stratified by age, sex, and race/ethnicity.
Conclusions—Smaller brachial FMD values are associated with higher rates of AF, sugge
Peripheral Arterial Disease and Risk of Atrial Fibrillation and Stroke: The Multi�Ethnic Study of Atherosclerosis
Background Peripheral arterial disease (PAD) shares several risk factors with atrial fibrillation (AF), and persons with PAD have an increased risk of stroke. It is unclear if PAD is associated with an increased risk for AF and whether this potential association explains the increased risk of stroke observed in those with PAD.
Methods and Results We examined the association between PAD, measured by ankle�brachial index (ABI), and incident AF and incident stroke, separately, in 6568 participants (mean age 62±10 years, 53% women, 62% nonwhite) from the Multi�Ethnic Study of Atherosclerosis (MESA). ABI values 1.4 defined PAD. AF was ascertained through review of hospital discharge records and from Medicare claims data until December 31, 2010. An independent adjudication committee ascertained stroke events. Cox regression was used to estimate hazard ratios and 95% CIs for the association between PAD and AF and stroke. Over a median follow�up of 8.5 years, 301 (4.6%) participants developed AF and 140 (2.1%) developed stroke. In a model adjusted for sociodemographics, cardiovascular risk factors, and potential confounders, PAD was associated with an increased risk of AF (hazard ratio 1.5, 95% CI 1.1 to 2.0). In a similar model, PAD was associated with incident stroke (hazard ratio 1.7, 95% CI 1.1 to 2.5), and the magnitude of risk was not different after inclusion of AF as a time�dependent covariate (hazard ratio 1.7, 95% CI 1.1 to 2.5).
Conclusions PAD is associated with an increased risk of AF and stroke in MESA. Potentially, the relationship between PAD and stroke is not mediated by AF
Relations Between Depressive Symptoms, Anxiety, and T Wave Abnormalities in Subjects Without Clinically-Apparent Cardiovascular Disease (from the Multi-Ethnic Study of Atherosclerosis [MESA])
The aim of this study was to test the hypothesis that depression and anxiety are associated with electrocardiographic (ECG) repolarization abnormalities in the Multi-Ethnic Study of Atherosclerosis (MESA), a cohort free of symptomatic cardiovascular disease. Depressive symptoms were assessed by using the Center for Epidemiologic Studies Depression Scale and trait anxiety symptoms by using the Spielberger State-Trait Anxiety Inventory; both were categorized according to uppermost quartile. T-wave inversions in ECG leads other than V1 to V3 were obtained from electrocardiograms obtained at rest during the baseline examination. Participants with major intraventricular conduction abnormalities and those taking antiarrhythmics, antidepressants, and/or antipsychotics were excluded. Logistic regression models were estimated with multivariable adjustment for traditional cardiovascular disease risk factors. Among 5,906 participants, elevated depressive symptoms were associated with increased odds of T-wave inversion after multivariable adjustment (odds ratio 2.02, 95% confidence interval 1.33 to 3.06, p = 0.001), whereas greater trait anxiety was associated with reduced odds of T-wave inversion (odds ratio 0.47, 95% confidence interval 0.29 to 0.77, p = 0.003). The divergent associations of depressive symptoms and trait anxiety with ECG T-wave inversions were similar in men and women, and these associations were present across the racial and ethnic subgroups (non-Hispanic white, African-American, Hispanic, and Chinese). In conclusion, symptoms of depression and anxiety were independently yet oppositely associated with ECG T-wave inversions. Negative emotions may have a differential impact on cardiovascular mortality through unique relations with cardiac repolarization
Curved Beam Computed Tomography based Structural Rigidity Analysis of Bones with Simulated Lytic Defect: A Comparative Study with Finite Element Analysis
In this paper, a CT based structural rigidity analysis (CTRA) method that incorporates bone intrinsic local curvature is introduced to assess the compressive failure load of human femur with simulated lytic defects. The proposed CTRA is based on a three dimensional curved beam theory to obtain critical stresses within the human femur model. To test the proposed method, ten human cadaveric femurs with and without simulated defects were mechanically tested under axial compression to failure. Quantitative computed tomography images were acquired from the samples, and CTRA and finite element analysis were performed to obtain the failure load as well as rigidities in both straight and curved cross sections. Experimental results were compared to the results obtained from FEA and CTRA. The failure loads predicated by curved beam CTRA and FEA are in agreement with experimental results. The results also show that the proposed method is an efficient and reliable method to find both the location and magnitude of failure load. Moreover, the results show that the proposed curved CTRA outperforms the regular straight beam CTRA, which ignores the bone intrinsic curvature and can be used as a useful tool in clinical practices
Gigantic retroperitoneal hematoma as a complication of anticoagulation therapy with heparin in therapeutic doses: a case report
<p>Abstract</p> <p>Introduction</p> <p>Spontaneous retroperitoneal hemorrhage is a distinct clinical entity that can present as a rare life-threatening event characterized by sudden onset of bleeding into the retroperitoneal space, occurring in association with bleeding disorders, intratumoral bleeding, or ruptures of any retroperitoneal organ or aneurysm. The spontaneous form is the most infrequent retroperitoneal hemorrhage, causing significant morbidity and representing a diagnostic challenge.</p> <p>Case presentation</p> <p>We report the case of a patient with coronary artery disease who presented with transient ischemic attack, in whom anticoagulant therapy with heparin precipitated a massive spontaneous atraumatic retroperitoneal hemorrhage (with international normalized ratio 2.4), which was treated conservatively.</p> <p>Conclusion</p> <p>Delay in diagnosis is potentially fatal and high clinical suspicion remains crucial. Finally, it is a matter of controversy whether retroperitoneal hematomas should be surgically evacuated or conservatively treated and the final decision should be made after taking into consideration patient's general condition and the possibility of permanent femoral or sciatic neuropathy due to compression syndrome.</p
Shoc2 Is Targeted to Late Endosomes and Required for Erk1/2 Activation in EGF-Stimulated Cells
Shoc2 is the putative scaffold protein that interacts with RAS and RAF, and positively regulates signaling to extracellular signal-regulated protein kinases 1 and 2 (ERK1/2). To elucidate the mechanism by which Shoc2 regulates ERK1/2 activation by the epidermal growth factor (EGF) receptor (EGFR), we studied subcellular localization of Shoc2. Upon EGFR activation, endogenous Shoc2 and red fluorescent protein tagged Shoc2 were translocated from the cytosol to a subset of late endosomes containing Rab7. The endosomal recruitment of Shoc2 was blocked by overexpression of a GDP-bound H-RAS (N17S) mutant and RNAi knockdown of clathrin, suggesting the requirement of RAS activity and clathrin-dependent endocytosis. RNAi depletion of Shoc2 strongly inhibited activation of ERK1/2 by low, physiological EGF concentrations, which was rescued by expression of wild-type recombinant Shoc2. In contrast, the Shoc2 (S2G) mutant, that is myristoylated and found in patients with the Noonan-like syndrome, did not rescue ERK1/2 activation in Shoc2-depleted cells. Shoc2 (S2G) was not located in late endosomes but was present on the plasma membrane and early endosomes. These data suggest that targeting of Shoc2 to late endosomes may facilitate EGFR-induced ERK activation under physiological conditions of cell stimulation by EGF, and therefore, may be involved in the spatiotemporal regulation of signaling through the RAS-RAF module
Whole shaft visibility and mechanical performance for active MR catheters using copper-nitinol braided polymer tubes
<p>Abstract</p> <p>Background</p> <p>Catheter visualization and tracking remains a challenge in interventional MR.</p> <p>Active guidewires can be made conspicuous in "profile" along their whole shaft exploiting metallic core wire and hypotube components that are intrinsic to their mechanical performance. Polymer-based catheters, on the other hand, offer no conductive medium to carry radio frequency waves. We developed a new "active" catheter design for interventional MR with mechanical performance resembling braided X-ray devices. Our 75 cm long hybrid catheter shaft incorporates a wire lattice in a polymer matrix, and contains three distal loop coils in a flexible and torquable 7Fr device. We explored the impact of braid material designs on radiofrequency and mechanical performance.</p> <p>Results</p> <p>The incorporation of copper wire into in a superelastic nitinol braided loopless antenna allowed good visualization of the whole shaft (70 cm) <it>in vitro </it>and <it>in vivo </it>in swine during real-time MR with 1.5 T scanner. Additional distal tip coils enhanced tip visibility. Increasing the copper:nitinol ratio in braiding configurations improved flexibility at the expense of torquability. We found a 16-wire braid of 1:1 copper:nitinol to have the optimum balance of mechanical (trackability, flexibility, torquability) and antenna (signal attenuation) properties. With this configuration, the temperature increase remained less than 2°C during real-time MR within 10 cm horizontal from the isocenter. The design was conspicuous <it>in vitro </it>and <it>in vivo</it>.</p> <p>Conclusion</p> <p>We have engineered a new loopless antenna configuration that imparts interventional MR catheters with satisfactory mechanical and imaging characteristics. This compact loopless antenna design can be generalized to visualize the whole shaft of any general-purpose polymer catheter to perform safe interventional procedures.</p
T-Lymphocytes Enable Osteoblast Maturation via IL-17F during the Early Phase of Fracture Repair
While it is well known that the presence of lymphocytes and cytokines are important for fracture healing, the exact role of the various cytokines expressed by cells of the immune system on osteoblast biology remains unclear. To study the role of inflammatory cytokines in fracture repair, we studied tibial bone healing in wild-type and Rag1−/− mice. Histological analysis, µCT stereology, biomechanical testing, calcein staining and quantitative RNA gene expression studies were performed on healing tibial fractures. These data provide support for Rag1−/− mice as a model of impaired fracture healing compared to wild-type. Moreover, the pro-inflammatory cytokine, IL-17F, was found to be a key mediator in the cellular response of the immune system in osteogenesis. In vitro studies showed that IL-17F alone stimulated osteoblast maturation. We propose a model in which the Th17 subset of T-lymphocytes produces IL-17F to stimulate bone healing. This is a pivotal link in advancing our current understanding of the molecular and cellular basis of fracture healing, which in turn may aid in optimizing fracture management and in the treatment of impaired bone healing
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