2,595 research outputs found
PSD-95 Is Associated with the Postsynaptic Density and Not with the Presynaptic Membrane at Forebrain Synapses
Get PDFPSD-95, a prominent protein component of the postsynaptic density (PSD) fraction from rat forebrain, has been localized by light microscopy to dendrites of hippocampal neurons (Cho et al., 1992) and to the presynaptic plexus of cerebellar basket cells (Kistner et al., 1993). Here we extend these studies to show that an affinity-purified antibody to PSD-95 labels the dendrites of most neurons in the forebrain and of a subset of neurons in the cerebellum. To confirm that PSD-95 is associated with the PSD at forebrain synapses and to clarify whether it is also associated with the presynaptic membrane, we employed immunogold electron microscopy of forebrain synaptosomes. Gold-labeled antibodies to PSD-95 labeled postsynaptic densities in both intact and lysed forebrain synaptosomes but did not label presynaptic terminals or the presynaptic membrane. The asymmetric distribution of PSD-95 at synapses contrasts with that of its homologs, disks-large and ZO-1, which are arranged symmetrically at septate and tight junctions, respectively
Identification of proteins in the postsynaptic density fraction by mass spectrometry
Get PDFOur understanding of the organization of postsynaptic signaling systems at excitatory synapses has been aided by the identification of proteins in the postsynaptic density (PSD) fraction, a subcellular fraction enriched in structures with the morphology of PSDs. In this study, we have completed the identification of most major proteins in the PSD fraction with the use of an analytical method based on mass spectrometry coupled with searching of the protein sequence databases. At least one protein in each of 26 prominent protein bands from the PSD fraction has now been identified. We found 7 proteins not previously known to be constituents of the PSD fraction and 24 that had previously been associated with the PSD by other methods. The newly identified proteins include the heavy chain of myosin-Va (dilute myosin), a motor protein thought to be involved in vesicle trafficking, and the mammalian homolog of the yeast septin protein cdc10, which is important for bud formation in yeast. Both myosin-Va and cdc10 are threefold to fivefold enriched in the PSD fraction over brain homogenates. Immunocytochemical localization of myosin-Va in cultured hippocampal neurons shows that it partially colocalizes with PSD-95 at synapses and is also diffusely localized in cell bodies, dendrites, and axons. Cdc10 has a punctate distribution in cell bodies and dendrites, with some of the puncta colocalizing with PSD-95. The results support a role for myosin-Va in transport of materials into spines and for septins in the formation or maintenance of spines
Recommended from our members
Physical activity counseling in medical school education: a systematic review
Get PDFBackground: Despite a large evidence base to demonstrate the health benefits of regular physical activity (PA), few physicians incorporate PA counseling into office visits. Inadequate medical training has been cited as a cause for this. This review describes curricular components and assesses the effectiveness of programs that have reported outcomes of PA counseling education in medical schools. Methods: The authors systematically searched MEDLINE, EMBASE, PsychINFO, and ERIC databases for articles published in English from 2000 through 2012 that met PICOS inclusion criteria of medical school programs with PA counseling skill development and evaluation of outcomes. An initial search yielded 1944 citations, and 11 studies representing 10 unique programs met criteria for this review. These studies were described and analyzed for study quality. Strength of evidence for six measured outcomes shared by multiple studies was also evaluated, that is, studentsâ awareness of benefits of PA, change in studentsâ attitudes toward PA, change in personal PA behaviors, improvements in PA counseling knowledge and skills, self-efficacy to conduct PA counseling, and change in attitude toward PA counseling. Results: Considerable heterogeneity of teaching methods, duration, and placement within the curriculum was noted. Weak research designs limited an optimal evaluation of effectiveness, that is, few provided pre-/post-intervention assessments, and/or included control comparisons, or met criteria for intervention transparency and control for risk of bias. The programs with the most evidence of improvement indicated positive changes in studentsâ attitudes toward PA, their PA counseling knowledge and skills, and their self-efficacy to conduct PA counseling. These programs were most likely to follow previous recommendations to include experiential learning, theoretically based frameworks, and studentsâ personal PA behaviors. Conclusions: Current results provide some support for previous recommendations, and current initiatives are underway that build upon these. However, evidence of improvements in physician practices and patient outcomes is lacking. Recommendations include future directions for curriculum development and more rigorous research designs
Bridging the gap between clinicians and fitness professionals
Get PDFObjective Health clubs (HC) and personal trainers (PT) are traditional outlets for the promotion of physical activity (PA) and exercise programming. As physicians are increasingly being called on to write exercise prescriptions for their patients, this study sought to investigate the level of integration between the healthcare and fitness systems.
Design An internet study was designed with five domains to understand physiciansâ: (1) overall perception of HC, (2) appropriateness and recommendation of HC and PT to their patients, (3) attitude regarding specific aspects of HC, (4) support of patient participation in HC sponsored exercise and (5) elements of HC that physicians would like to know for referral.
Methods An electronic survey was sent to members of two mailing lists of primary care and sports medicine specialty physicians during 2011â2012.
Results On a Likert scale of 1â10 412 physicians reported being familiar with HC (8.9±2.1), indicated a favourable view of HC (7.9±2.2), and believe HC to be an appropriate venue for their patients (7.5±2.3). However, physicians only recommend HC to 41%±28% of their patients and PT for only 21%±21.6% of patients. Physicians ranked expense and convenience as the most problematic elements of HC (8.1±2.1 and 6.3±2.5, respectively). 72% of physicians indicated cost as most concerning when recommending a specific HC.
Conclusion HC and PT are a significant implementation system for the promotion of physical activity, yet physicians are concerned with several elements of HC and are not adequately relying on this partnership to promote physical activity to their patients
Running marathons in high school: A 5-year review of injury in a structured training program
Get PDFObjective: The aim in this study was to quantify the number, nature, and severity of injuries sustained by male and female high school students who took part in a running training program that culminated in the completion of a half or full marathon. Design: This study is a retrospective clinical audit. Methods: Injury reports from high school students (grades 9 â 12) who participated in a half or full marathon 30-week progressive training program comprising four training days per week (three running days and one cross-training day) were reviewed. The number of runners completing a marathon, together with the number, nature, severity of injuries, and treatment types, as reported to the program physiotherapist, were the main outcome measures. Results: Program completion was 96% (n = 448/469). Of all participants, 186 (39.6 %) were injured, with 14 withdrawing from the program due to injury. For those who completed a marathon, 172 (38 %) reported 205 musculoskeletal injuries (age of injured runners: 16.3 ± 1.1 years; 88 girls (51.2 %) and 84 boys (48.8 %)). More than half (n = 113, 55.1 %) of the reported injuries were soft tissue injuries. Most injuries were localized to the lower leg (n = 88, 42.9 %) and were of a minor nature (n = 181, 90 %), requiring only 1â2 treatments. Conclusions: There was a low number of relatively minor injuries for high school participants taking part in a graduated and supervised marathon training program. The injury definition was conservative (i.e., any attendance to physiotherapist) and the relative severity of injuries was minor (i.e., requiring 1 â 2 treatment sessions). Overall, these results do not support a need to restrict high school students from taking part in marathon running, though continued emphasis on graduated program development and close supervision of young participants is recommended
A Case of SIADH After Bowel Preparation for Routine Colonoscopy
Get PDFElectrolyte abnormalities, including hyponatremia, are a known outcome of bowel preparations used for colonoscopy. Severe and symptomatic hyponatremia after bowel preparation is uncommon and occurs due to excessive release of ADH among other contributing factors. Risk factors for developing hyponatremia after bowel preparation include increased age, female gender, kidney disease, heart failure, and use of various medications. We present the case of a 78-year-old female who presented with altered mental status and possible seizures after completing bowel preparation with polyethylene glycol for a colonoscopy. Serum and urine studies were consistent with SIADH. She required fluid restriction, hypertonic saline, and sodium supplementation over several days to return her sodium levels and neurologic status to baseline. This case emphasizes that physicians should be aware of the potential for severe electrolyte abnormalities that may occur after oral bowel preparations in preparation for colonoscopy, especially in patients with multiple risk factors
Exercise professional education, qualifications, and certifications: A content analysis of job postings in the United States
Get PDFIntroduction: Growth in the field of clinical exercise science and the potential impacts on overall health and wellbeing have driven the need for qualified, clinically trained, exercise professionals. And yet, it is not well understood what specific credentials employers are seeking when hiring exercise professionals. Purpose: The purpose of the study was to examine the qualification requirements for professionals seeking employment in exercise science, exercise physiology, kinesiology or equivalent fields. Methods: Search platforms Indeed.com and USAJobs.gov were examined within a two week period in 2022. Search terms included âExercise Physiologyâ, âExercise Scienceâ, âExercise Professionalâ, âExercise Prescriptionâ, âExercise Specialistâ, and âKinesiologyâ. Results: A total of n = 739 jobs were retrieved and n = 615 jobs were included: Exercise Science (n = 227), Kinesiology (n = 210), Exercise Physiology (n = 91), Exercise specialist (n = 53), and Exercise prescription (n = 32). Over 70% of the jobs analyzed required a bachelor\u27s degree with the remainder requiring various levels of education. The primary certification required was personal trainer (n = 94), followed by strength and conditioning specialist (n = 33), clinical exercise physiologist (n = 26), group exercise (n = 17), exercise specialist (n = 10), and exercise physiologist (n = 5). Four job focus areas were determined: academic teaching and research, general fitness and worksite wellness, athletic performance and rehabilitation, clinical exercise specialist all with varying levels of degree and certification requirements. Discussion: Job postings related to exercise related professions are varied across the United States with wide-ranging education, credentialing and certification requirements. These findings indicate the timely need for outreach to employers to highlight changing credentialing requirements due to evolving accreditation standards
Implementation barriers to integrating exercise as medicine in oncology: An ecological scoping review
Get PDFPurpose
While calls have been made for exercise to become standard practice in oncology, barriers to implementation in real-world settings are not well described. This systematic scoping review aimed to comprehensively describe barriers impeding integration of exercise into routine oncology care within healthcare systems.
Methods
A systematic literature search was conducted across six electronic databases (since 2010) to identify barriers to implementing exercise into real-world settings. An ecological framework was used to classify barriers according to their respective level within the healthcare system.
Results
A total of 1,376 results were retrieved; 50 articles describing implementation barriers in real-world exercise oncology settings were reviewed. Two hundred and forty-three barriers were identified across all levels of the healthcare system. Nearly 40% of barriers existed at the organizational level (nâ=â93). Lack of structures to support exercise integration and absence of staff/resources to facilitate its delivery were the most common issues reported. Despite the frequency of barriers at the organizational level, organizational stakeholders were largely absent from the research.
Conclusions
Implementing exercise into routine cancer care is hindered by a web of interrelated barriers across all levels of the healthcare system. Organizational barriers are central to most issues. Future work should take an interdisciplinary approach to explore best practices for overcoming implementation barriers, with organizations as a central focus.
Implications for Cancer Survivors
This blueprint of implementation barriers highlights critical issues that need to be overcome to ensure people with cancer have access to the therapeutic benefits of exercise during treatment and beyond
- âŠ
