879 resultados para development need
Resumo:
Purpose: Cardiomyocytes are terminally differentiated cells in the adult heart and ischemia and cardiotoxic compounds can lead to cell death and irreversible decline of cardiac function. As testing platforms, isolated organs and primary cells from rodents have been the standard in research and toxicology, but there is a need for better models that more faithfully recapitulate native human biology. Hence, a new in vitro model comprising the advantages of 3D cell culture and the availability of induced pluripotent stem cells (iPSC) from human origin was developed and characterized. Methods: Human cardiomyocytes (CMs) derived from induced pluripotent stem cells (iPSCs) were studied in standard 2D culture and as cardiac microtissues (MTs) formed in hanging drops. 2D cultures were examined using immunofluorescence microscopy and Western blotting while the cardiac MTs were subjected to immunofluorescence, contractility, and pharmacological investigations. Results: iPSC-derived CMs in 2D culture showed well-formed myofibrils, cell-cell contacts positive for connexin-43, and other typical cardiac proteins. The cells reacted to pro-hypertrophic growth factors with a substantial increase in myofibrils and sarcomeric proteins. In hanging drop cultures, iPSC-derived cardiomyocytes formed spheroidal MTs within 4 days showing a homogeneous tissue structure with well-developed myofibrils extending throughout the whole spheroid without a necrotic core. MTs showed spontaneous contractions for more than 4 weeks that were recorded by optical motion tracking, sensitive to temperature, and responsive to electrical pacing. Contractile pharmacology was tested with several agents known to modulate cardiac rate and viability. Calcium-transients underlay the contractile activity and were also responsive to electrical stimulation, caffeine-induced Ca2+-release, extracellular calcium levels. Conclusions: 3D culture using iPSC-derived human cardiomyocytes provides an organoid human-based cellular platform that is free of necrosis and recapitulates vital cardiac functionality, thereby providing new and promising relevant model for the evaluation and development of new therapies and detection of cardiotoxicity.
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The sustainable development paradigm raises issues of global, intra- and intergenerational social equity as well as respect for nature, and economic welfare. Switzerland is confronted by these issues within its own country, and has a moral responsibility vis-a-vis the rest of the world. Syndromes of global change are affecting many eco-regions, not only in developing and transition countries, but to a lesser extent also the affluent countries. Switzerland as a nation has an impact on syndromes through its far-reaching economic activities, which are non-sustainable. At the global level, more modest consumption patterns, a considerably slowed demographic change, a nonconsumptive but sustainable use of natural resources, and conflict transformation are the main prerequisites for improving sustainability. Switzerland's current contribution to sustainability is much less than what it could be, hence the need for additional action along general principles in,accordance with Swiss traditions and innovative potentials. A number of concrete actions could be taken immediately. These are: labelling the socially and ecologically sustainable production of goods and services, and their negotiation at WTO level; enhancing international cooperation and research; strengthening education and research for sustainability, and emphasizing energy and material flux efficiency at home and abroad.
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The need for wildlife health surveillance has become increasingly recognized. However, comprehensive programs which cover a wide spectrum of species, pathogens and geographic areas are still lacking in most European countries and practical examples of systems in place remain scarce. This article provides an overview of the organization of wildlife health surveillance in Switzerland, with a focus on the development, current strategies and the activities of the national program carried out by the Centre for Fish and Wildlife Health (FIWI), University of Bern. This documentation may stimulate on-going discussions on the design and development of national wildlife health surveillance programs in other countries. Investigations into wildlife health in Switzerland date back to the 1950s. The FIWI acts as a national competence center for wildlife diseases on mandate of the Swiss federal authorities. The mandate includes four main activities: disease diagnostics, research, consulting and teaching. In line with this, the FIWI has made continuous efforts to strengthen a national network of field partners and implemented strategies to facilitate long-term and metastudies.
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Preparing teachers to effectively teach culturally diverse students, teacher educators advocate for the use of cross-cultural field experiences, including international study abroad programs. This paper reports on a qualitative case study of two pre-service teachers’ intercultural development during a semester-long teacher education study abroad program in London, England. Findings indicate that international experiences provide a catalyst to move pre-service teachers forward in their intercultural development. Implications include the need for multicultural teacher educators to take a developmental approach to pre-service teacher education informed by theories of intercultural development and cultural learning developed within intercultural communications.
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Over 50% of sporadic tumors in humans have a p53 mutation highlighting its importance as a tumor suppressor. Considering additional mutations in other genes involved in p53 pathways, every tumor probably has mutant p53 or impaired p53-mediated functions. In response to a variety of cellular and genotoxic stresses, p53, mainly through its transcriptional activity, induces pathways involved in apoptosis and growth arrest. In these circumstances and under normal situations, p53 must be tightly regulated. Mdm2 is an important regulator of p53. Mdm2 inhibits p53 function by binding and blocking its transactivation domain. In addition, Mdm2 helps target p53 for degradation through its E3 ligase activity. Mdm2 null mice are embryonic lethal due to apoptosis in the blastocysts. However, a p53 null background rescues this lethality demonstrating the importance of the p53-Mdm2 interaction, particularly during development. The lethality of the Mdm2 null mouse prior to implantation limits the ability to investigate the role of Mdm2 in regulating p53 in a temporal and tissue specific manner. Does p53 need to be regulated in all tissues throughout the life of a mouse? Does Mdm2 always have to regulate it? To address these questions, we created a conditional Mdm2 allele. The conditional allele, Mdm2FM, in the presence of Cre recombinase results in the deletion of exons 5 and 6 of Mdm2 (most of the p53 binding domain) and represents a null allele. ^ The Mdm2FM allele was crossed with a heart muscle specific Cre expressing mouse (α-myosin heavy chain promoter driven Cre) to ask whether Mdm2 acts as a negative regulator of p53 in the heart. The heart is the most prominent organ early in embryogenesis and is shaped by cell death and proliferation. p53 does not appear to be active in the heart in response to some types of stress, so it remained to be determined if it has to be regulated in normal heart development. Loss of Mdm2 in the heart results in heart defects as early as E9.5. Loss of Mdm2 results in stabilized p53 and apoptosis. This apoptosis leads to a thinning of the myocardial wall particularly in the ventricles and abnormal ventricular structure. Eventually the abnormal heart fails resulting in lethality by E13.5. The embryonic lethality is rescued in a p53 null background. Thus, Mdm2 is important in regulating p53 in the development of the heart. ^
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Institutional Review Boards (IRBs) are the primary gatekeepers for the protection of ethical standards of federally regulated research on human subjects in this country. This paper focuses on what general, broad measures that may be instituted or enhanced to exemplify a "model IRB". This is done by examining the current regulatory standards of federally regulated IRBs, not private or commercial boards, and how many of those standards have been found either inadequate or not generally understood or followed. The analysis includes suggestions on how to bring about changes in order to make the IRB process more efficient, less subject to litigation, and create standardized educational protocols for members. The paper also considers how to include better oversight for multi-center research, increased centralization of IRBs, utilization of Data Safety Monitoring Boards when necessary, payment for research protocol review, voluntary accreditation, and the institution of evaluation/quality assurance programs. ^ This is a policy study utilizing secondary analysis of publicly available data. Therefore, the research for this paper focuses on scholarly medical/legal journals, web information from the Department of Health and Human Services, Federal Drug Administration, and the Office of the Inspector General, Accreditation Programs, law review articles, and current regulations applicable to the relevant portions of the paper. ^ Two issues are found to be consistently cited by the literature as major concerns. One is a need for basic, standardized educational requirements across all IRBs and its members, and secondly, much stricter and more informed management of continuing research. There is no federally regulated formal education system currently in place for IRB members, except for certain NIH-based trials. Also, IRBs are not keeping up with research once a study has begun, and although regulated to do so, it does not appear to be a great priority. This is the area most in danger of increased litigation. Other issues such as voluntary accreditation and outcomes evaluation are slowing gaining steam as the processes are becoming more available and more sought after, such as JCAHO accrediting of hospitals. ^ Adopting the principles discussed in this paper should promote better use of a local IRBs time, money, and expertise for protecting the vulnerable population in their care. Without further improvements to the system, there is concern that private and commercial IRBs will attempt to create a monopoly on much of the clinical research in the future as they are not as heavily regulated and can therefore offer companies quicker and more convenient reviews. IRBs need to consider the advantages of charging for their unique and important services as a cost of doing business. More importantly, there must be a minimum standard of education for all IRB members in the area of the ethical standards of human research and a greater emphasis placed on the follow-up of ongoing research as this is the most critical time for study participants and may soon lead to the largest area for litigation. Additionally, there should be a centralized IRB for multi-site trials or a study website with important information affecting the trial in real time. There needs to be development of standards and metrics to assess the performance of the IRBs for quality assurance and outcome evaluations. The boards should not be content to run the business of human subjects' research without determining how well that function is actually being carried out. It is important that federally regulated IRBs provide excellence in human research and promote those values most important to the public at large.^
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Children and adults frequently skip breakfast and rates are currently increasing. In addition, the food choices made for breakfast are not always healthy ones. Breakfast skipping, in conjunction with unhealthy breakfast choices, leads to impaired cognitive functioning, poor nutrient intake, and overweight. In response to these public health issues, Skip To Breakfast, a behaviorally based school and family program, was created to increase consistent and healthful breakfast consumption among ethnically diverse fifth grade students and their families, using Intervention Mapping™. Four classroom lessons and four parent newsletters were used to deliver the intervention. For this project, a healthy, "3 Star Breakfast" was promoted, and included a serving each of dairy product, whole grain, and fruit, each with an emphasis on being low in fat and sugar. The goal of this project was to evaluate the feasibility and acceptability of the intervention. A pilot-test of the intervention was conducted in one classroom, in a school in Houston, during the Fall 2007 semester. A qualitative evaluation of the intervention was conducted, which included focus groups with students, phone interviews of parents, process evaluation data from the classroom teacher, and direct observation. Sixteen students and six parents participated in the study. Data were recorded and themes were identified. Initial results showed there is a need for such programs. Based on the initial feedback, edits were made to the intervention and program. Results showed high acceptability among the teacher, students, and parents. It became apparent that students were not reliably getting the parent newsletters to their parents to read, so a change to the protocol was made, in which students will receive incentives for having parents read newsletters and return signed forms, to increase parent participation. Other changes included small modifications to the curriculum, such as, clarifying instructions, changing in-class assignments to homework assignments, and including background reading materials for the teacher. The main trial is planned to be carried out in Spring 2008, in two elementary schools, utilizing four, fifth grade classes from each, with one school acting as the control and one as the intervention school. Results from this study can be used as an adjunct to the Coordinated Approach To Child Health (CATCH) program. ^
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Hydrazine $\rm (N\sb2H\sb4),$ an important liquid propellant and derivative chemical for pharmaceuticals and pesticides, produces coma and convulsions sometimes resulting in death. Hyperammonia was found in rabbits exposed to 18 mg/Kg of hydrazine. Results of Part One of this study of rabbits emphasize the importance of acute ammonia toxicity during the first three hours following exposure to hydrazine. At no time during this post exposure period did a significant reduction of hydrazine to ammonia occur. Therefore, the elevated blood ammonia was apparently secondary to the effects of hydrazine on metabolic pathways. Further, the results support the theory of competitive inhibition of ammonia by hydrazine and emphasize the need to monitor plasma ammonia following toxic exposure to hydrazine.^ In Part Two, urea, ammonia, CO$\sb2,$ pH, glucose, sodium, potassium, chloride and creatinine were measured for up to 4 hours following injection of 18 mg/Kg of hydrazine in each of two groups of five rabbits. One group received normal saline and the other group received 5% dextrose and water/normal saline. Hyperammonemia, minimal metabolic acidosis and hyperglycemia without increased urea were found in the rabbits receiving normal saline intravenous infusion and hydrazine injection. Hence, hypoglycemia does not appear to play a role in the development of hyperammonemia. A significant difference in the elevated ammonia levels between the two groups receiving dextrose and water/normal saline and normal saline at 1 hour occurred. There was no significant difference in the elevated ammonia levels seen between the two groups receiving dextrose and water/normal saline and normal saline at 2.5 and 4 hours. Thus at 1 hour the group receiving dextrose was able to utilize excess glucose to detoxify ammonia, while at 2.5 and 4 hours there was no significant difference in the two groups' ability to detoxify ammonia.^ Findings support the theory that hydrazine inhibits the formation of urea resulting in hyperammonemia. Results suggest that hydrazine at 18 mg/Kg, a known hypoglycemic agent, causes serious hyperammonemia without increasing urea production during hyperglycemia. These experiments support a unified theory for the toxic mechanism of action of hydrazine, i.e., the intermediary metabolic effects of hydrazine are brought about by the formation of hydrazones which encumber ATP synthesis and vitamin B$\sb6$ enzymatic reactions. ^
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This dissertation focuses on Project HOPE, an American medical aid agency, and its work in Tunisia. More specifically this is a study of the implementation strategies of those HOPE sponsored projects and programs designed to solve the problems of high morbidity and infant mortality rates due to environmentally related diarrheal and enteric diseases. Several environmental health programs and projects developed in cooperation with Tunisian counterparts are described and analyzed. These include (1) a paramedical manpower training program; (2) a national hospital sanitation and infection control program; (3) a community sewage disposal project; (4) a well reconstruction project; and (5) a solid-waste disposal project for a hospital.^ After independence, Tunisia, like many developing countries, encountered several difficulties which hindered progress toward solving basic environmental health problems and prompted a request for aid. This study discusses the need for all who work in development programs to recognize and assess those difficulties or constraints which affect the program planning process, including those latent cultural and political constraints which not only exist within the host country but within the aid agency as well. For example, failure to recognize cultural differences may adversely affect the attitudes of the host staff towards their work and towards the aid agency and its task. These factors, therefore, play a significant role in influencing program development decisions and must be taken into account in order to maximize the probability of successful outcomes.^ In 1969 Project HOPE was asked by the Tunisian government to assist the Ministry of Health in solving its health manpower problems. HOPE responded with several programs, one of which concerned the training of public health nurses, sanitary technicians, and aids at Tunisia's school of public health in Nabeul. The outcome of that program as well as the strategies used in its development are analyzed. Also, certain questions are addressed such as, what should the indicators of success be, and when is the time right to phase out?^ Another HOPE program analyzed involved hospital sanitation and infection control. Certain generic aspects of basic hospital sanitation procedures were documented and presented in the form of a process model which was later used as a "microplan" in setting up similar programs in other Tunisian hospitals. In this study the details of the "microplan" are discussed. The development of a nation-wide program without any further need of external assistance illustrated the success of HOPE's implementation strategies.^ Finally, although it is known that the high incidence of enteric disease in developing countries is due to poor environmental sanitation and poor hygiene practices, efforts by aid agencies to correct these conditions have often resulted in failure. Project HOPE's strategy was to maximize limited resources by using a systems approach to program development and by becoming actively involved in the design and implementation of environmental health projects utilizing "appropriate" technology. Three innovative projects and their implementation strategies (including technical specifications) are described.^ It is advocated that if aid agencies are to make any progress in helping developing countries basic sanitation problems, they must take an interdisciplinary approach to progrm development and play an active role in helping counterparts seek and identify appropriate technologies which are socially and economically acceptable. ^
Resumo:
The development of the Alcohol Treatment Profile System (ATPS) was described and an evaluation of its perceived value by various States was undertaken, The ATPS is a treatment needs assessment tool based on the unification of several large national epidemiologic and treatment data sets. It was developed by the National Institute on Alcohol Abuse and Alcoholism (NIAAA) and responsibility for its creation was given to the NIAAA's Alcohol Epidemiologic Data System (AEDS). The ATPS merges county-level measures of alcohol problem prevalence (the specially constructed AEDS Alcohol Problem Indicators), indicating "need" for treatment, and treatment utilization measures (the National Drug and Alcohol Treatment Utilization Survey), indicating treatment "demand." The capabilities of the ATPS in the unique planning and policy-making settings of several States were evaluated.^
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Background: Poor communication among health care providers is cited as the most common cause of sentinel events involving patients. Sign-out of patient data at the change of clinician shifts is a component of communication that is especially vulnerable to errors. Sign-outs are particularly extensive and complex in intensive care units (ICUs). There is a paucity of validated tools to assess ICU sign-outs. ^ Objective: To design a valid and reliable survey tool to assess the perceptions of Pediatric ICU (PICU) clinicians about sign-out. ^ Design: Cross-sectional, web-based survey ^ Setting: Academic hospital, 31-bed PICU ^ Subjects: Attending faculty, fellows, nurse practitioners and physician assistants. ^ Interventions: A survey was designed with input from a focus group and administered to PICU clinicians. Test-retest reliability, internal consistency and validity of the survey tool were assessed. ^ Measurements and Main Results: Forty-eight PICU clinicians agreed to participate. We had 42(88%) and 40(83%) responses in the test and retest phases. The mean scores for the ten survey items ranged from 2.79 to 3.67 on a five point Likert scale with no significant test-retest difference and a Pearson correlation between pre and post answers of 0.65. The survey item scores showed internal consistency with a Cronbach's Alpha of 0.85. Exploratory factor analysis revealed three constructs: efficacy of sign-out process, recipient satisfaction and content applicability. Seventy eight % clinicians affirmed the need for improvement of the sign-out process and 83% confirmed the need for face- to-face verbal sign-out. A system-based sign-out format was favored by fellows and advanced level practitioners while attendings preferred a problem-based format (p=0.003). ^ Conclusions: We developed a valid and reliable survey to assess clinician perceptions about the ICU sign-out process. These results can be used to design a verbal template to improve and standardize the sign-out process.^
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The development of targeted therapy involve many challenges. Our study will address some of the key issues involved in biomarker identification and clinical trial design. In our study, we propose two biomarker selection methods, and then apply them in two different clinical trial designs for targeted therapy development. In particular, we propose a Bayesian two-step lasso procedure for biomarker selection in the proportional hazards model in Chapter 2. In the first step of this strategy, we use the Bayesian group lasso to identify the important marker groups, wherein each group contains the main effect of a single marker and its interactions with treatments. In the second step, we zoom in to select each individual marker and the interactions between markers and treatments in order to identify prognostic or predictive markers using the Bayesian adaptive lasso. In Chapter 3, we propose a Bayesian two-stage adaptive design for targeted therapy development while implementing the variable selection method given in Chapter 2. In Chapter 4, we proposed an alternate frequentist adaptive randomization strategy for situations where a large number of biomarkers need to be incorporated in the study design. We also propose a new adaptive randomization rule, which takes into account the variations associated with the point estimates of survival times. In all of our designs, we seek to identify the key markers that are either prognostic or predictive with respect to treatment. We are going to use extensive simulation to evaluate the operating characteristics of our methods.^
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The rationale for policy interest in career development services, and the way in which this rationale is being strengthened by the current transformations in work and career, are discussed. The potential roles of public policy in relation to career development services are explored, along with ways in which such services can influence the policy-making process. A range of policy issues related to making career development services available to all throughout life are identified: these include the nature of such services, where they are to be located, and who is to pay for them. It is argued that there is a need for stronger structures and processes to bring together career development practitioners with policy- makers and other stakeholder interests in order to address tasks of common concern, at both national and international levels.
Resumo:
The rationale for policy interest in career development services, and the way in which this rationale is being strengthened by the current transformations in work and career, are discussed. The potential roles of public policy in relation to career development services are explored, along with ways in which such services can influence the policy-making process. A range of policy issues related to making career development services available to all throughout life are identified: these include the nature of such services, where they are to be located, and who is to pay for them. It is argued that there is a need for stronger structures and processes to bring together career development practitioners with policy- makers and other stakeholder interests in order to address tasks of common concern, at both national and international levels.