992 resultados para HEART INVOLVEMENT
Resumo:
CONTEXT: In populations of older adults, prediction of coronary heart disease (CHD) events through traditional risk factors is less accurate than in middle-aged adults. Electrocardiographic (ECG) abnormalities are common in older adults and might be of value for CHD prediction. OBJECTIVE: To determine whether baseline ECG abnormalities or development of new and persistent ECG abnormalities are associated with increased CHD events. DESIGN, SETTING, AND PARTICIPANTS: A population-based study of 2192 white and black older adults aged 70 to 79 years from the Health, Aging, and Body Composition Study (Health ABC Study) without known cardiovascular disease. Adjudicated CHD events were collected over 8 years between 1997-1998 and 2006-2007. Baseline and 4-year ECG abnormalities were classified according to the Minnesota Code as major and minor. Using Cox proportional hazards regression models, the addition of ECG abnormalities to traditional risk factors were examined to predict CHD events. MAIN OUTCOME MEASURE: Adjudicated CHD events (acute myocardial infarction [MI], CHD death, and hospitalization for angina or coronary revascularization). RESULTS: At baseline, 276 participants (13%) had minor and 506 (23%) had major ECG abnormalities. During follow-up, 351 participants had CHD events (96 CHD deaths, 101 acute MIs, and 154 hospitalizations for angina or coronary revascularizations). Both baseline minor and major ECG abnormalities were associated with an increased risk of CHD after adjustment for traditional risk factors (17.2 per 1000 person-years among those with no abnormalities; 29.3 per 1000 person-years; hazard ratio [HR], 1.35; 95% CI, 1.02-1.81; for minor abnormalities; and 31.6 per 1000 person-years; HR, 1.51; 95% CI, 1.20-1.90; for major abnormalities). When ECG abnormalities were added to a model containing traditional risk factors alone, 13.6% of intermediate-risk participants with both major and minor ECG abnormalities were correctly reclassified (overall net reclassification improvement [NRI], 7.4%; 95% CI, 3.1%-19.0%; integrated discrimination improvement, 0.99%; 95% CI, 0.32%-2.15%). After 4 years, 208 participants had new and 416 had persistent abnormalities. Both new and persistent ECG abnormalities were associated with an increased risk of subsequent CHD events (HR, 2.01; 95% CI, 1.33-3.02; and HR, 1.66; 95% CI, 1.18-2.34; respectively). When added to the Framingham Risk Score, the NRI was not significant (5.7%; 95% CI, -0.4% to 11.8%). CONCLUSIONS: Major and minor ECG abnormalities among older adults were associated with an increased risk of CHD events. Depending on the model, adding ECG abnormalities was associated with improved risk prediction beyond traditional risk factors.
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QUESTIONS UNDER STUDY: The field of heart transplantation has seen substantial progress in the last 40 years. The breakthroughs in long-term survival were followed by a period of stagnation in the last decade. This review summarises current recommendations for the identification of candidates for heart transplantation and their immunological and non-immunological postoperative follow-up. RESULTS: The progress made in the treatment of patients with advanced heart failure has considerably changed the profile of candidates for heart transplantation. Patients are older, and the load of co-morbidities is more important requiring careful evaluation for candidacy. Long-standing research in the field of immunosuppression made available various drugs, which decrease the risk of acute allograft rejection and prolong survival after heart transplantation. Powerful new molecules are entering early phase clinical studies, suggesting further improvement in the near future. As a consequence, treatment of non-immunological co-morbidity after heart transplantation will gain in importance, however, the base of evidence guiding current recommendations is poor. CONCLUSIONS: The substantial progress in heart failure treatment and immunosuppression after heart transplantation has changed the profile of heart transplant recipients. The arrival of new molecules will provide additional alternatives for immunosuppressive treatment while studies have to address non-immunological treatment in order to improve long-term survival after heart transplantation.
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BACKGROUND: Earlobe crease (ELC) has been associated with cardiovascular diseases (CVD) or risk factors (CVRF) and could be a marker predisposing to CVD. However, most studies studied only a small number of CVRF and no complete assessment of the associations between ELC and CVRF has been performed in a single study. METHODS: Population-based study (n = 4635, 46.7 % men) conducted between 2009 and 2012 in Lausanne, Switzerland. RESULTS: Eight hundred six participants (17.4 %) had an ELC. Presence of ELC was associated with male gender and older age. After adjusting for age and gender (and medication whenever necessary), presence of ELC was significantly (p < 0.05) associated with higher levels of body mass index (BMI) [adjusted mean ± standard error: 27.0 ± 0.2 vs. 26.02 ± 0.07 kg/m(2)], triglycerides [1.40 ± 0.03 vs. 1.36 ± 0.01 mmol/L] and insulin [8.8 ± 0.2 vs. 8.3 ± 0.1 μIU/mL]; lower levels of HDL cholesterol [1.61 ± 0.02 vs. 1.64 ± 0.01 mmol/L]; higher frequency of abdominal obesity [odds ratio and (95 % confidence interval) 1.20 (1.02; 1.42)]; hypertension [1.41 (1.18; 1.67)]; diabetes [1.43 (1.15; 1.79)]; high HOMA-IR [1.19 (1.00; 1.42)]; metabolic syndrome [1.28 (1.08; 1.51)] and history of CVD [1.55 (1.21; 1.98)]. No associations were found between ELC and estimated cardiovascular risk, inflammatory or liver markers. After further adjustment on BMI, only the associations between ELC and hypertension [1.30 (1.08; 1.56)] and history of CVD [1.47 (1.14; 1.89)] remained significant. For history of CVD, further adjustment on diabetes, hypertension, total cholesterol and smoking led to similar results [1.36 (1.05; 1.77)]. CONCLUSION: In this community-based sample ELC was significantly and independently associated with hypertension and history of CVD.
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The majority of transcatheter aortic valve implantations, structural heart procedures and the newly developed transcatheter mitral valve repair and replacement are traditionally performed either through a transfemoral or a transapical access site, depending on the presence of severe peripheral vascular disease or anatomic limitations. The transapical approach, which carries specific advantages related to its antegrade nature and the short distance between the introduction site and the cardiac target, is traditionally performed through a left anterolateral mini-thoracotomy and requires rib retractors, soft tissue retractors and reinforced apical sutures to secure, at first, the left ventricular apex for the introduction of the stent-valve delivery systems and then to seal the access site at the end of the procedure. However, despite the advent of low-profile apical sheaths and newly designed delivery systems, the apical approach represents a challenge for the surgeon, as it has the risk of apical tear, life-threatening apical bleeding, myocardial damage, coronary damage and infections. Last but not least, the use of large-calibre stent-valve delivery systems and devices through standard mini-thoracotomies compromises any attempt to perform transapical transcatheter structural heart procedures entirely percutaneously, as happens with the transfemoral access site, or via a thoracoscopic or a miniaturised video-assisted percutaneous technique. During the past few years, prototypes of apical access and closure devices for transapical heart valve procedures have been developed and tested to make this standardised successful procedure easier. Some of them represent an important step towards the development of truly percutaneous transcatheter transapical heart valve procedures in the clinical setting.
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The objective of this thesis is to better understand customer’s role in lean startup methodology. The aim is to find out how customers are involved in lean startup methodology implantation and increase the likelihood of new venture survival. This study emphasizes the usage of customers in shaping of new product development processes within companies, through iteration and constant communication. This communication facilitates the development of features that are requested by the customers and enhances the prospects of the new venture. The empirical part of the study is a single qualitative case study that uses action research to implement the lean startup methodology into a pre-revenue venture and examines its customer involvement processes. The studied case company is Karaoke d.o.o., developing a game called kParty. The study used the theory discussed in the literature review: customer involvement (in the survey and interviews conducted for the lean startup methodology), lean principles (through the implementation of lean startup methodology) and lean startup methodology, which are the central building parts of this thesis as a whole. The thesis contributes to the understanding of customer involvement in lean startup methodology, while giving practical implications of customer orientation and product market fitting.
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Community service participation can have a positive impact on development, especially for youth. Although researchers have found positive outcomes, there has been a notable decline in youth participation over the past few years (Statistics Canada, 2000). Given the positive outcomes and current decline, it has been argued that youth should be encouraged to get involved in service activities. In the present study, quantitative and qualitative data were collected to determine factors that would help youth to initiate and sustain service, along with examining the quality of their experience. Eighty-two university undergraduate students (23 men), ranging in age from 17-20 years completed a 60-minute self-report questionnaire. Initiating and sustaining factors, motivational systems (similar to approach and avoidance dimensions), activity dimensions {Structure, Supportive Social Environment), quality of experience {Positive, Stress-Challenge), and future intention to participate in community service were measured. Eight participants also completed a 20-minute telephone interview to complement and expand on the quantitative data collected. Some initiating and sustaining factors were specific to individuals higher on the avoidance dimension, while others were relevant to those higher on the approach dimension. Several factors also were important to individuals regardless of their motivational system orientation. Positive quality of experience was related positively to experiencing a supportive social environment. In addition, women rated their community service as more positive than did men. A predicted interaction between the avoidance dimension and Structure in predicting positive quality of experience was not supported; however, positive quality of experience was predicted by the interaction of the approach dimension and Structure. A tested interaction between the avoidance dimension and Supportive Social Environment in predicting positive quality of experience was not supported. Similarly, a predicted interaction between the approach dimension and Supportive Social Environment in predicting positive experience quality was not supported. However, Supportive Social Environment was positively related to positive quality of experience. No support was found for a mediational role for positive quality of experience or stress-challenge quality of experience in exploring the relation between motivational orientation and fiiture intention to engage in service activities. The results of this study suggest that participating in a service environment that is supportive and provides the opportunity for social interactions with others would promote positive quality of experience and help youth sustain involvement. Thus, to help youth have positive experiences and to remain active in service, it is important for service agencies to promote these types of environments. In addition, some initiating and sustaining factors were specific to youth higher on the avoidance dimension and some were relevant to youth higher on the approach dimension. Therefore, service agencies may need to consider using different recruitment and retention strategies, depending on the type of youth they wish to recruit.
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The use of certain perfonnance enhancing substances and methods has been defined as a major ethical breach by parties involved in the governance of highperfonnance sport. As a result, elite athletes worldwide are subject to rules and regulations set out in international and national anti-doping policies. Existing literature on the development of policies such as the World Anti-Doping Code and The Canadian antiDoping Program suggests a sport system in which athletes are rarely meaningfully involved in policy development (Houlihan, 2004a). Additionally, it is suggested that this lack of involvement is reflective of a similar lack of involvement in other areas of governance concerning athletes' lives. The purpose ofthis thesis is to examine the history and current state of athletes' involvement in the anti-doping policy process in Canada's high-perfonnance sport system. It includes discussion and analysis of recently conducted interviews with those involved in the policy process as well as an analysis of relevant documents, including anti-doping policies. The findings demonstrate that Canadian athletes have not been significantly involved in the creation of recently developed antidoping policies and that a re-evaluation of current policies is necessary to more fully recognize the reality of athletes' lives in Canada's high-perfonnance sport system and their rights within that system.
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This study explored the impact of training parents and children concurrently in principled negotiation skills for the purpose of developing negotiation skills and problem solving abilities in children. A second experimental group was utilized to determine the viability of negotiation skills training of junior elementary students for the purpose of improving problem solving and conflict resolving abilities. The student population in each experimental group was trained using The Program for Young Negotiators (Curhan, 1996). A control group was also established using the remaining grade four and five students attending the participating school. These students did not receive training as part of this study. Student group distribution was as follows: Experimental group 1 (students with parent participant) consisted of 10 (5 grade five and 5 grade 4 students), Experimental group 2 students without parent participant) consisted of 48 (20 grade 4 and 28 grade 5 students), and the Control group 3 (55 grade 4 and 5 students). The impact of training was measured using the Five Factor Negotiation Scale developed for use with the Program for Young Negotiators (Curhan, 1996). This measure was employed as a pre- and post-test questionnaire to the total student population, (113 students) to determine levels of ability in each of the key elements of negotiation, personal initiative, collaboration, communication, conflict based perspective taking, and conflict resolution approach (Nakkula & Nikitopoulos, unpublished). This measure has a coefficient alpha of .75 which is acceptable for this type of affective instrument. As well, open ended ability questions designed to measure ability, knowledge, and behaviour as they relate to negotiation skill application were given to the total student population, (113 students). Finally, journals were maintained by the students in both experimental groups, and informal feedback discussions were held with students and parents participating in the study.The intent of using both qualitative and quantitative measures was to provide an overall perspective of student abilities as they related to principled negotiation skills. While the quantitative measures were from the student perspective, more qualitative information was sought from parents and teachers through informal interviews, discussions, and use of confidential feedback cards. For analysis purposes, the ability questions were randomly selected for Experimental group 2 and Control group 3 in an effort to balance the groups more equitably with Experimental group 1. The findings of this study indicate that students of the junior elementary school age can be taught how to perceive conflict in a more constructive way. However, they are not as likely to use their skills when the conflict is with a sibling as they are with a peer, a teacher, or a parent. While no statistically significant differences between mean scores for Experimental groups 1 and 2 exist some subtle differences are noted. Overall, increases in mean scores for grade 4 students exceeded the increases for grade 5 students within Experimental group 1 . The implication being that younger students benefit more from having a parent trained in principled negoUation skills than older students. The skill level of a parent in principled negotiation can not be underesUmated. Without a consistent and effective role model the likelihood of developing student skill level to a point of automaticity is greatly reduced. Enough so that perhaps the emphasis should be placed on training parents more so than the students.
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Gene therapy is predicated upon efficient gene transfer. While viral vectors are the method of choice for transformation efficiency, the immunogenicity and safety concerns remain problematic. Non-viral vectors, on the other hand, have shown high degrees of safety and are mostly non-immunogenic in nature. However, non-viral vectors usually suffer from low levels oftransformation efficiency and transgene expression. Thus, increasing transformation efficiency ofnon-viral vectors, in particular by calcium phosphate co-precipitation technique, is a way of generating a suitable vector for gene therapy and is the aim of this study. It is a long known fact that different cell lines have different transfection efficiencies regardless oftransfection methodology (Lin et a!., 1994). Using commonly available cell lines Madine-Darby Bovine Kidney (MDBK), HeLa and Human Embryonic Kidney (HEK-293), we have shown a decreasing trend ofDNase activity based on a plasmid digestion assay. From densitometry studies, as much as a 40% reduction in DNase activity was observed when comparing HEK-293 (least active) to MDBK (most active). Using various biochemical assays, it was determined that DNase y, in particular, was expressed more highly in MDBK cells than both HeLa and HEK-293. Upon cloning of the bovine DNase y gene, we utilized the sequence information to construct antisense expressing plasmids via both traditional antisense RNA (pASDGneoM) and siRNA (psiRNA-S4, psiRNA-S11 and psiRNA-S16). For the construction ofpASDGneoM, the 3' end of the DNase y was inserted in opposite orientation under a cytomegalovirus (CMV) promoter such that the expression ofRNA complementary to the DNase 2 ymRNA occurred. For siRNA plasmids, the sequence was screened to yield optimal short sequences for siRNA inhibition. The silencing ofbovine DNase y led to an increase in transfection efficiency based on traditional calcium phosphate co-precipitation technique; stable clones of siRNA-producing MDBK cell lines (psiRNA-S4 Bland psiRNA-S4 B4) both demol).strated 4-fold increases in transfection efficiency. Furthermore, serial transfection of antisense DNase y plasmid pASDGneoM and reporter pCMV-~ showed a maximum of 8-fold increase in transfection efficiency when the two separate transfections were carried out 4 hours apart (i.e. transfection ofpASDGneoM, separated by four hours, then transfection ofpCMV-~). Together, these results demonstrate the involvement ofDNase y in reducing transfection efficiency, at least by traditional calcium phosphate technique.
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The purpose of this study was to explore the experiences of 5 stakeholder groups—students, parents, community organization representatives, guidance counsellors, and secondary school principals—in dealing with a mandatory secondary school graduation requirement in Ontario. The requirement is that students must complete 40 hours of eligible community involvement activities during their high school years in order to graduate. Ten stakeholders were interviewed regarding the nature of the community involvement program, what makes it work, and suggestions for improvement. The study found that although this program has the potential to provide a meaningful experience for students, and students are seen to gain from their experience in multiple ways, it depends substantially on the commitment of students, educators, and community organizations to make it worthwhile. Stakeholders recommended changes to the current program, which included making it a more structured process that would increase the consistency ofhow this program is implemented, finding ways to curb cheating and to reduce the administrative burden on schools, having more support from the Ontario provincial government and Ontario Ministry of Education and Training in the promotion and communication of this program, and developing partnerships between community organizations and schools to enrich the application of this program. This study concludes with a recommendation that the Ontario Ministry of Education and Training consider introducing Service-Learning, a curriculum-based experiential service and learning process, as an enhancement to the current community involvement program.
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The current classification system for spinal cord injury (SCI) considers only somatic information and neglects autonomic damage after injiuy. Heart rate variability (HRV) has the potential to be a valuable measure of cardiac autonomic control after (SCI). Five individuals with tetraplegia and four able-bodied controls underwent 1 min continuous ECG recordings during rest, after Metoprolol administration (max dose=3x5mg) and after Atropine administration (0.02mg/kg) in both supine and 40° head-up tilt. After Metoprolol administration there was a 61.8% decrease in the LF:HF ratio in the SCI participants suggesting that the LF:HF ratio is a reflection of cardiac sympathetic outflow. After Atropine administration there was a 99.1% decrease in the HF power in the SCI participants suggesting that HF power is highly representative of cardiac parasympathetic outflow. There were no significant differences between the SCI and able-bodied participants. Thus, HRV measures are a valid index of cardiac autonomic control after SCI.
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Studies on the steady state behavior of soluble cytochrome c oxidase are extensive. These studies have examined the influence of ionic strength and pH and may provide answers to questions such as the link between proton translocation and charge separation. The present study examined the influence of external bulk pH on ApH formation, biphasic kinetics, and steady state reduction of cytochromes c and a of cytochrome c oxidase in proteoliposomes. Bulk pH has an appreciable effect on ApH formation and steady state reduction levels of cytochromes c and 8. Bulk pH affected total Vmax and Km at the low affinity binding site of cytochrome c. This study also examined the influence of bovine serum albumin and free fatty acids on proton pumping activity in bovine heart proteoliposomes. Proton pumping activity decreased after treatment with BSA, and was subsequently reinstated after further treatment with FFA. Much study in the superfamily of haem/copper oxidases has recently been devoted to the bacterial oxidases. The present study has examined some protein composition characteristics and bioenergetic features of Bacillus subtilis cytochrome caa3 oxidase. Results provide evidence for the structural composition of the enzyme in relation to the covalently bound cytochrome c to the oxidas~. Bioenergetically, caa3 COV showed appreciable proton pumping activity. Steady state analysis of the caa3 COV showed significantly different cytochrome c and a reduction characteristics compared to the bovine enzyme.
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Extracellular, non-flagellar appendages, termed fimbriae are widespread among fungi. Fungal fimbriae range in diameter from 6-10 nm and exhibit lengths of up to 30 ~m. Fungal fimbriae have been implicated in several functions: adhesion, conjugation and flocculation. A possible role of fimbriae in host-mycoparasite interactions was the focus of this study . Using electron microscopy, fimbriae were observed on the surfaces of Mortiere lla cande labrum, Mortie re lla pusi lla and Phascolomyces articulosus with diameter means of 9.1±0.4 nm, 9.4±0.5 nm and 8.6±0.6 nm, respectively, and lengths of up to 25 ~m. Fimbriae were not observed on the surface of the mycoparasite, Piptocephalis virginiana. Polyclonal antiserum (AU) prepared against the fimbrial protein of Ustilago violacea cross-reacted with 60 and 57 kDa M. candelabrum proteins. In addition, AU cross-reacted with 64 kDa proteins from both M. pusilla and P. articulosus. The proteins that cross-reacted with AU were electroeluted from polyacrylamide gels and were shown to subsequently form fibrils. The diameter means for the electroeluted fibrils were: for M. candelabrum 9.7±0.3 nm, M. pusilla 8.4±0.6 nm and P articulosus 9.2±0.5 nm. Finally, to ascertain the role of fimbriae in host-mycoparasite interactions, AU was incubated with P. virginiana and M. pusilla (mycoparasite/susceptible host) and with P. virginiana and P . articulosus (mycoparasite/ resistant host). It was observed that AU decreased significantly the level of contact between P. virginiana and M. pusilla and between P. virginiana and P. articulosus in comparison to prelmmune serum treatments. Thus, it was proposed that fimbriae might play recognition and attachment roles in early events of mycoparasitism.