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81.

Background

Research emphasises the need for instructional methods and tools which can improve Basic Life Support (BLS) performance or reduce instructional time.

Aim

To investigate the effect of peer evaluation to improve reciprocal learning with task cards as instructional tools for acquiring BLS.

Methods

A total of 78 kinesiology students from a Belgian university were paired and randomised across two groups to learn BLS in 20 min with task cards. In the control group, students worked together in a defined doer–helper relationship and switched roles every 5 min. In the peer evaluation group, students followed the same co-operation procedure as in the control group. In addition, 1 min before every switching of roles, the helper evaluated the doer's performance. All BLS skills were individually assessed on a Laerdal AED Resusci Anne mannequin (Laerdal Medical, Vilvoorde, Belgium) using the Laerdal PC-Skill reporting system. A total BLS score was calculated and performance was measured before training (baseline), immediately after training (intervention) and 2 weeks later (retention).

Results

Significantly more students from the evaluation group remembered and consequently performed all BLS skills at intervention (P = 0.03). No significant differences were found between groups for main cardiopulmonary resuscitation (CPR) variables and total BLS scores at baseline, intervention and retention. Both groups achieved more than 70% of the maximum BLS score at intervention and retention.

Conclusions

This study demonstrated that 20 min reciprocal-learning setting with task cards is an effective method to learn BLS. The implementation of peer evaluation in this setting has an immediate, however small, positive impact on BLS skill learning.  相似文献   
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84.
Heat shock proteins play a key regulatory role in cellular defense. To investigate the role of the inducible 70-kDa heat shock protein (HSP70) in skeletal muscle atrophy and subsequent recovery, soleus (SOL) and extensor digitorum longus (EDL) muscles from overexpressing HSP70 transgenic mice were immobilized for 7 days and subsequently released from immobilization and evaluated after 7 days. Histological analysis showed that there was a decrease in cross-sectional area of type II myofiber from EDL and types I and II myofiber from SOL muscles at 7-day immobilization in both wild-type and HSP70 mice. At 7-day recovery, EDL and SOL myofibers from HSP70 mice, but not from wild-type mice, recovered their size. Muscle tetanic contraction decreased only in SOL muscles from wild-type mice at both 7-day immobilization and 7-day recovery; however, it was unaltered in the respective groups from HSP70 mice. Although no effect in a fatigue protocol was observed among groups, we noticed a better contractile performance of EDL muscles from overexpressing HSP70 groups as compared to their matched wild-type groups. The number of NCAM positive-satellite cells reduced after immobilization and recovery in both EDL and SOL muscles from wild-type mice, but it was unchanged in the muscles from HSP70 mice. These results suggest that HSP70 improves structural and functional recovery of skeletal muscle after disuse atrophy, and this effect might be associated with preservation of satellite cell amount.  相似文献   
85.
Hypertension induces vascular alterations that are associated with up-regulation of matrix metalloproteinases (MMPs). While these alterations may be blunted by doxycycline, a non-selective MMPs inhibitor, no previous study has examined the effects of different doses of doxycycline on these alterations. This is important because doxycycline has been used at sub-antimicrobial doses, and the use of lower doses may prevent the emergence of antibiotic-resistant microorganisms. We studied the effects of doxycycline at 3, 10 and 30 mg/kg per day on the vascular alterations found in the rat two kidney-one clip (2K1C) hypertension (n = 20 rats/group). Systolic blood pressure (SBP) was monitored during 4 weeks of treatment. We assessed endothelium-dependent and independent relaxations. Quantitative morphometry of structural changes in the aortic wall was studied, and aortic MMP-2 levels/proteolytic activity were determined by gelatin and in situ zymography, respectively. All treatments attenuated the increases in SBP in hypertensive rats (195.4 ± 3.9 versus 177.2 ± 6.2, 176.3 ± 4.5, and 173 ± 5.1 mmHg in 2K1C hypertensive rats treated with vehicle, or doxycycline at 3, 10, 30 mg/kg per day, respectively (all p < 0.01). However, only the highest dose prevented 2K1C-induced reduction in endothelium-dependent vasorelaxation (p < 0.05), vascular hypertrophy and increases in MMP-2 levels (all p < 0.05). In conclusion, our results suggest that relatively lower doses of doxycycline do not attenuate the vascular alterations found in the 2K1C hypertension model, and only the highest dose of doxycycline affects MMPs and vascular structure. Our results support the idea that the effects of doxycycline on MMP-2 and vascular structure are pressure independent.  相似文献   
86.
Increased reactive oxygen species (ROS) promote matrix metalloproteinase (MMP) activities and may underlie cardiomyocyte injury and the degradation of cardiac troponin I (cTI) during acute pulmonary thromboembolism (APT). We examined whether pretreatment or therapy with tempol (a ROS scavenger) prevents MMP activation and cardiomyocyte injury of APT. Anesthetized sheep received tempol infusion (1.0 mg kg(-1) min(-1), i.v.) or saline starting 30 min before or 30 min after APT (autologous blood clots). Control animals received saline. Hemodynamic measurements were performed. MMPs were studied in the right ventricle (RV) by gelatin zymography, fluorimetric activity assay, and in situ zymography. The ROS levels were determined in the RV and cTI were measured in serum samples. APT increased the pulmonary arterial pressure and pulmonary vascular resistance by 146 and 164%, respectively. Pretreatment or therapy with tempol attenuated these increases. While APT increased RV + dP/dt (max), tempol infusions had no effects. APT increased RV MMP-9 (but not MMP-2) levels. In line with these findings, APT increased RV MMP activities, and this finding was confirmed by in situ zymography. APT increased the RV ROS levels and tempol infusion, before or after APT, and blunted APT-induced increases in MMP-9 levels, MMP activities, in situ MMP activities, and ROS levels in the RV. cTI concentrations increased after APT, and tempol attenuated these increases. RV oxidative stress after APT increases the RV MMP activities, leading to the degradation of sarcomeric proteins, including cTI. Antioxidant treatment may prevent MMP activation and protect against cardiomyocyte injury after APT.  相似文献   
87.
Progress in understanding the pathophysiology of abdominal aortic aneurysms (AAA) is dependent in part on the development and application of effective animal models that recapitulate key aspects of the disease. The objective was to produce an experimental model of AAA in rats by combining two potential causes of metalloproteinase (MMP) secretion: inflammation and turbulent blood flow. Male Wistar rats were randomly divided in four groups: Injury, Stenosis, Aneurysm and Control (40/group). The Injury group received a traumatic injury to the external aortic wall. The Stenosis group received an extrinsic stenosis at a corresponding location. The Aneurysm group received both the injury and stenosis simultaneously, and the Control group received a sham operation. Animals were euthanized at days 1, 3, 7 and 15. Aorta and/or aneurysms were collected and the fragments were fixed for morphologic, immunohistochemistry and morphometric analyses or frozen for MMP assays. AAAs had developed by day 3 in 60-70% of the animals, reaching an aortic dilatation ratio of more than 300%, exhibiting intense wall remodelling initiated at the adventitia and characterized by an obvious inflammatory infiltrate, mesenchymal proliferation, neoangiogenesis, elastin degradation and collagen deposition. Immunohistochemistry and zymography studies displayed significantly increased expressions of MMP-2 and MMP-9 in aneurysm walls compared to other groups. The haemo-dynamic alterations caused by the stenosis may have provided additional contribution to the MMPs liberation. This new model illustrated that AAA can be multifactorial and confirmed the key roles of MMP-2 and MMP-9 in this dynamic remodelling process.  相似文献   
88.
Tele-health is more than an innovative alternative; it is an excellent tool that enables access to health and education in health, making it possible to minimize distances, optimize time and reduce costs. Based on these advantages, some Brazilian Universities have used these actions in strategies of education, research and extension, aiming at the application of Tele-health in Brazil. In that way, the Bauru School of Dentistry - University of São Paulo (FOB-USP) has applied the use of information and communication technologies in health by means of a "Tele-Health League" (TL), in order to diagnose, prevent and treat diseases, in addition to educate the population and health services.

Objective

The present study aims to introduce the characteristics of the Tele-Health League of FOB-USP, as well as the development of its projects.

Material and Methods

The Tele-Health League consisted as a Diffusion Course approved by the Provost of Culture and Academic Extension of the University of São Paulo. It is composed as a large group enclosing professoriate coordinator, academician principal, contributing professors and league members, those, diversified between undergraduates students, graduated, health employees, technology and information areas. The participant members are evaluated by the presence frequency (minimum of 85%), and by the performance of tests and paperwork about the theoretical content provided.

Results

In four years of activities, the TLFOB-USP obtained a high satisfaction index (90%), an increased number of vacancies due to the interest to become a member, more commitment of the professors of the University and the accomplishment of association with other Brazilian leagues. It is emphasized that the approval percentage of the course results in approval from approximately half of its members. Also, it is important to identify and repair the causes related to the quitting of some members.

Conclusions

The results showed that the TLFOB-USP members, adjoining to the professor''s participants, develop projects in Tele-helth, in Tele-aid and Tele-education areas, thus resulting in the involvement of the University and the community.  相似文献   
89.
Radiotherapy, alone or associated with surgery or chemotherapy, produces a significant increase in cure rates for many malignancies of the head and neck region. However, high doses of radiation in large areas, including the oral mucosa, may result in several undesired reactions that manifest during or after the completion of therapy. The multidisciplinary management is the best alternative to minimize or even prevent such reactions, and the dentist has a fundamental role in this context. This paper reviews the literature related to the main oral sequelae from head and neck radiotherapy and establishes clinical oral management protocol for these irradiated patients.  相似文献   
90.
The aim of this study was to assess the effect of leucine supplementation on elements of the ubiquitin–proteasome system (UPS) in rat skeletal muscle during immobilization. This effect was evaluated by submitting the animals to a leucine supplementation protocol during hindlimb immobilization, after which different parameters were determined, including: muscle mass; cross‐sectional area (CSA); gene expression of E3 ligases/deubiquitinating enzymes; content of ubiquitinated proteins; and rate of protein synthesis. Our results show that leucine supplementation attenuates soleus muscle mass loss driven by immobilization. In addition, the marked decrease in the CSA in soleus muscle type I fibers, but not type II fibers, induced by immobilization was minimized by leucine feeding. Interestingly, leucine supplementation severely minimized the early transient increase in E3 ligase [muscle ring finger 1 (MuRF1) and muscle atrophy F‐box (MAFbx)/atrogin‐1] gene expression observed during immobilization. The reduced peak of E3 ligase gene expression was paralleled by a decreased content of ubiquitinated proteins during leucine feeding. The protein synthesis rate decreased by immobilization and was not affected by leucine supplementation. Our results strongly suggest that leucine supplementation attenuates muscle wasting induced by immobilization via minimizing gene expression of E3 ligases, which consequently could downregulate UPS‐driven protein degradation. It is notable that leucine supplementation does not restore decreased protein synthesis driven by immobilization. Muscle Nerve, 2010  相似文献   
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