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Peer assisted learning (PAL) is implemented in many undergraduate medical programs, largely in classroom-based learning. There is relatively less knowledge about the use of PAL in clinical education environments. This study explores how PAL is experienced and perceived by Year 3 medical students who are new to the clinical environment. Students across urban/metropolitan sites, rural sites, and an international site (Malaysia) were invited to participate in a cross-sectional survey; 54 of a potential 415 students responded. We found that students are already using PAL on their clinical placements and can see its value. PAL not only occurs in structured events within the curriculum, such as Problem Based Learning (PBL) or bedside tutorials, but also in unstructured and student-prompted ways, such as debriefing cases at lunch time, observation of practice on the ward, and self-selected study groups outside clinical placement. These PAL activities in the clinical environment are yet to be mapped within the literature. Importantly, contrary to previous studies, PAL was not reported to increase competition amongst students and a drive for social acceptance was not reported to hinder honest peer-to-peer feedback. Despite the "organic" episodes of PAL on clinical placements, students reported that they needed more PAL education and training. Students are reticent to judge their peers' performance, not because of social pressures, but due to a lack of confidence in knowing performance targets. Observational research is suggested as a way to further explore these trends and to inform development of helpful PAL strategies for learners.

This study explored the contribution of peer-assisted learning (PAL) in the development of evaluative judgement capacity; the ability to understand work quality and apply those standards to appraising performance. The study employed a mixed methods approach, collecting self-reported survey data, observations of, and reflective interviews with, the medical students observed. Participants were in their first year of clinical placements. Data were thematically analysed. Students indicated that PAL contributed to both the comprehension of notions of quality, and the practice of making comparisons between a given performance and the standards. Emergent themes included peer story-telling, direct observation of performance, and peer-based feedback, all of which helped students to define "work quality". By participating in PAL, students were required to make comparisons, therefore using the standards of practice and gaining a deeper understanding of them. The data revealed tensions in that peers were seen as less threatening than supervisors with the advantage of increasing learners' appetites for thoughtful "intellectual risk taking". Despite this reported advantage of peer engagement, learners still expressed a preference for feedback from senior teachers as more trusted sources of clinical knowledge. While this study suggests that PAL already contributes to the development of evaluative judgement, further steps could be taken to formalise PAL in clinical placements to improve learners' capacity to make accurate judgements on the performance of self and others. Further experimental studies are necessary to confirm the best methods of using PAL to develop evaluative judgement. This may include both students and educators as instigators of PAL in the workplace.

Endurance training represents one extreme in the continuum of skeletal muscle plasticity. The molecular signals elicited in response to acute and chronic exercise and the integration of multiple intracellular pathways are incompletely understood. We determined the effect of 10 days of intensified cycle training on signal transduction in nine inactive males in response to a 1-h acute bout of cycling at the same absolute workload (164 [+ or -] 9 W). Muscle biopsies were taken at rest and immediately and 3 h after the acute exercise. The metabolic signaling pathways, including AMP-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR), demonstrated divergent regulation by exercise after training. AMPK phosphorylation increased in response to exercise (~16-fold; P < 0.05), which was abrogated posttraining (P < 0.01). In contrast, mTOR phosphorylation increased in response to exercise (~2-fold; P < 0.01), which was augmented posttraining (P < 0.01) in the presence of increased mTOR expression (P < 0.05). Exercise elicited divergent effects on mitogen-activated protein kinase (MAPK) pathways after training, with exercise-induced extracellular signal-regulated kinase (ERK) 1/2 phosphorylation being abolished (P < 0.01) and p38 MAPK maintained. Finally, calmodulin kinase II (CaMKII) exercise-induced phosphorylation and activity were maintained (P < 0.01), despite increased expression (~2-fold; P < 0.05). In conclusion, 10 days of intensified endurance training attenuated AMPK, ERK1/2, and mTOR, but not CaMKII and p38 MAPK signaling, highlighting molecular pathways important for rapid functional adaptations and maintenance in response to intensified endurance exercise and training. adenosine 5'-monophosphate-activated protein kinase; protein kinase B; mitogen-activated protein kinases; calmodulin kinase II; mammalian target of rapamycin; glycogen

The major isoform of nitric oxide synthase (NOS) in skeletal muscle is the splice variant of neuronal NOS, termed nNOS[micro]. Exercise training increases nNOS[micro] protein levels in rat skeletal muscle, but data in humans are conflicting. We performed two studies to determine 1) whether resting nNOS[micro] protein expression is greater in skeletal muscle of 10 endurance-trained athletes compared with 11 sedentary individuals (study 1) and 2) whether intense short-term (10 days) exercise training increases resting nNOS[micro] protein (within whole muscle and also within types I, IIa, and IIx fibers) in eight sedentary individuals (study 2). In study 1, nNOS[micro] protein was ~60% higher (P < 0.05) in endurance-trained athletes compared with the sedentary participants. In study 2, nNOS[micro] protein expression was similar in types I, IIa, and IIx fibers before training. Ten days of intense exercise training significantly (P < 0.05) increased nNOS[micro] protein levels in types I, IIa, and IIx fibers, a finding that was validated by using whole muscle samples. Endothelial NOS and inducible NOS protein were barely detectable in the skeletal muscle samples. In conclusion, nNOS[micro] protein expression is greater in endurance-trained individuals when compared with sedentary individuals. Ten days of intense exercise is also sufficient to increase nNOS[micro] expression in untrained individuals, due to uniform increases of nNOS[micro] within types I, IIa, and IIx fibers. nitric oxide; nitric oxide synthase; immunohistochemistry

Skeletal muscle displays enormous plasticity to respond to contractile activity with muscle from strength- (ST) and endurance-trained (ET) athletes representing diverse states of the adaptation continuum. Training adaptation can be viewed as the accumulation of specific proteins. Hence, the altered gene expression that allows for changes in protein concentration is of major importance for any training adaptation. Accordingly, the aim of the present study was to quantify acute subcellular responses in muscle to habitual and unfamiliar exercise. After 24-h diet/exercise control, 13 male subjects (7 ST and 6 ET) performed a random order of either resistance (8 x 5 maximal leg extensions) or endurance exercise (1 h of cycling at 70% peak [O.sub.2] uptake). Muscle biopsies were taken from vastus lateralis at rest and 3 h after exercise. Gene expression was analyzed using real-time PCR with changes normalized relative to preexercise values. After cycling exercise, peroxisome proliferator-activated receptor-[lambda] coactivator-l[alpha] (ET ~8.5 -fold, ST ~10-fold, P < 0.001), pyruvate dehydrogenase kinase-4 (PDK-4; ET ~26-fold, ST ~39-fold), vascular endothelial growth factor (VEGF; ET ~4.5-fold, ST ~4-fold), and muscle atrophy F-box protein (MAFbx) (ET ~2-fold, ST ~0.4-fold) mRNA increased in both groups, whereas MyoD (~3-fold), myogenin (~0.9-fold), and myostatin (~2-fold) mRNA increased in ET but not in ST (P < 0.05). After resistance exercise PDK-4 (~7-fold, P < 0.01) and MyoD (~0.7-fold) increased, whereas MAFbx (~0.7-fold) and myostatin (~0.6-fold) decreased in ET but not in ST. We conclude that prior training history can modify the acute gene responses in skeletal muscle to subsequent exercise. cycling; resistance exercise; training; adaptation

Research was conducted to test the effect of angiotensin II infusion in vivo on basal cortisol concentrations and fetal adrenal responsiveness to an adrenocorticotropic hormone challenge. There was no evidence to indicate that angiotensin II infusion in vivo controls fetal basal cortisol concentrations or adrenal responsiveness in the last week of gestation. Thus, the findings are not in agreement with the view that angiotensin II is a negative modulator of adrenal function in the ovine fetus.

There is evidence that increasing carbohydrate (CHO) availability during exercise by raising preexercise muscle glycogen levels attenuates the activation of AMPK[alpha]2 during exercise in humans. Similarly, increasing glucose levels decreases AMPK[alpha]2 activity in rat skeletal muscle in vitro. We examined the effect of CHO ingestion on skeletal muscle AMPK signaling during exercise in nine active male subjects who completed two 120-min bouts of cycling exercise at 65 [+ or -] 1% go2 peak. In a randomized, counterbalanced order, subjects ingested either an 8% CHO solution or a placebo solution during exercise. Compared with the placebo trial, CHO ingestion significantly (P < 0.05) increased plasma glucose levels and tracer-determined glucose disappearance. Exercise-induced increases in muscle-calculated free AMP (17.7- vs. 11.8-fold), muscle lactate (3.3- vs. 1.8-fold), and plasma epinephrine were reduced by CHO ingestion. However, the exercise-induced increases in skeletal muscle AMPK[alpha]2 activity, AMPK[alpha]2 Thr(172) phosphorylation and acetyl-CoA Ser(222) phosphorylation, were essentially identical in the two trials. These findings indicate that AMPK activation in skeletal muscle during exercise in humans is not sensitive to changes in plasma glucose levels in the normal range. Furthermore, the rise in plasma epinephrine levels in response to exercise was greatly suppressed by CHO ingestion without altering AMPK signaling, raising the possibility that epinephrine does not directly control AMPK activity during muscle contraction under these conditions in vivo. adenosine monophosphate-activated protein kinase; acetyl-coenzyme A carboxylase; contraction; glucose uptake; metabolism doi:10.1152/ajpendo.00023.2006.

Chen, Zhi-Ping, Glenn K. McConell, Belinda J. Michell, Rodney J. Snow, Benedict J. Canny, and Bruce E. Kemp. AMPK signaling in contracting human skeletal muscle: acetyl-CoA carboxylase and NO synthase phosphorylation. Am J Physiol Endocrinol Metab 279: E1202-E1206, 2000.--AMP-activated protein kinase (AMPK) is a metabolic stress-sensing protein kinase responsible for coordinating metabolism and energy demand. In rodents, exercise accelerates fatty acid metabolism, enhances glucose uptake, and stimulates nitric oxide (NO) production in skeletal muscle. AMPK phosphorylates and inhibits acetyl-coenzyme A (CoA) carboxylase (ACC) and enhances GLUT-4 translocation. It has been reported that human skeletal muscle malonyl-CoA levels do not change in response to exercise, suggesting that other mechanisms besides inhibition of ACC may be operating to accelerate fatty acid oxidation. Here, we show that a 30-s bicycle sprint exercise increases the activity of the human skeletal muscle AMPK-[Alpha]1 and -[Alpha]2 isoforms approximately two- to threefold and the phosphorylation of ACC at [Ser.sup.79] (AMPK phosphorylation site) -8.5-fold. Under these conditions, there is also an -5.5-fold increase in phosphorylation of neuronal NO synthase- [micro] (nNOS [micro]) at [Ser.sup.1451]. These observations support the concept that inhibition of ACC is an important component in stimulating fatty acid oxidation in response to exercise and that there is coordinated regulation of nNOS [micro] to protect the muscle from ischemia/metabolic stress. AMP-activated protein kinase; nitric oxide synthase; exercise

Phenomenon: Peer learning has many benefits and can assist students in gaining the educational skills required in future years when they become teachers themselves. Peer learning may be particularly useful in clinical learning environments, where students report feeling marginalized, overwhelmed, and unsupported. Educational interventions often fail in the workplace environment, as they are often conceived in the “ideal” rather than the complex, messy real world. This work sought to explore barriers and facilitators to implementing peer learning activities in a clinical curriculum.Approach: Previous peer learning research results and a matrix of empirically derived peer learning activities were presented to local clinical education experts to generate discussion around the realities of implementing such activities. Potential barriers and limitations of and strategies for implementing peer learning in clinical education were the focus of the individual interviews.Findings: Thematic analysis of the data identified three key considerations for real-world implementation of peer learning: culture, epistemic authority, and the primacy of patient-centered care. Strategies for peer learning implementation were also developed from themes within the data, focusing on developing a culture of safety in which peer learning could be undertaken, engaging both educators and students, and establishing expectations for the use of peer learning.Insights: This study identified considerations and strategies for the implementation of peer learning activities, which took into account both educator and student roles. Reported challenges were reflective of those identified within the literature. The resultant framework may aid others in anticipating implementation challenges. Further work is required to test the framework's application in other contexts and its effect on learner outcomes. [ABSTRACT FROM PUBLISHER]