948 resultados para Dual-use ethics
Resumo:
Study Design. In vitro biomechanical investigation of the screw-holding capacity. Objective. To evaluate the effect of repetitive screw-hole use on the insertional torque and retentive strength of vertebral system screws. Summary and Background Data. Placement and removal of vertebral system screws is sometimes necessary during the surgical procedures in order to assess the walls of the pilot hole. This procedure may compromise the holding capacity of the implant. Methods. Screws with outer diameter measuring 5, 6, and 7 mm were inserted into wood, polyurethane, polyethylene, and cancellous bone cylindrical blocks. The pilot holes were made with drills of a smaller, equal, or wider diameter than the inner screw diameter. Three experimental groups were established based on the number of insertions and reinsertions of the screws and subgroups were created according to the outer diameter of the screw and the diameter of the pilot hole used. Results. A reduction of screw-holding capacity was observed between the first and the following insertions regardless the anchorage material. The pattern of reduction of retentive strength was not similar to the pattern of torque reduction. The pullout strength was more pronounced between the first and the last insertions, while the torque decreased more proportionally from the first to the last insertions. Conclusion. Insertion and reinsertion of the screws of the vertebral fixation system used in the present study reduced the insertion torque and screw purchase.
Resumo:
The prevention and treatment of diseases related to changes in body composition require accurate methods for the measurement of body composition. However, few studies have dealt specifically with the assessment of body composition of undernourished older subjects by different methodologies. To assess the body composition of undernourished older subjects by two different methods, dual energy x-ray absorptiometry (DXA) and bioelectric impedance (BIA), and to compare results with those of an eutrophic group. The study model was cross-sectional; the study was performed at the University Hospital of the School of Medicine of Ribeiro Preto, University of So Paulo, Brazil. Forty-one male volunteers aged 62 to 91 years. The groups were selected on the basis of anamnesis, physical examination and nutritional assessment according to the Mini Nutritional Assessment (MNA) score. Body composition was assessed by DXA and BIA. Body weight, arm and calf circumference, body mass index (BMI), fat free mass (FFM) and fat mass (FM) were significantly lower in the undernourished group as compared to the eutrophic group. There were no significant differences between FFM and FM mean values determined by DXA and BIA in both groups, but the agreement between methods in the undernourished group was less strong. Our results suggest caution when BIA is to be applied in studies including undernourished older subjects. This study does not support BIA as an accurate method for the individual assessment of body composition.
Resumo:
The assessment of food intake is essential for the development of dietetic interventions. Accuracy is low when intake is assessed by questionnaires, the under-reporting of food intake being frequent. Most such studies, however, were performed in developed countries and there is little data about the older population of developing nations. This study aimed to verify the total energy expenditure (TEE) of independent older Brazilians living in an urban area, through the doubly labelled water (DLW) method and to compare it with the reported energy intake obtained through the application of a food frequency questionnaire (FFQ). Initially, 100 volunteers aged from 60 to 75 years had their body composition determined by dual-energy X-ray absorptiometry (DEXA). Five volunteers of each quartile of body fat percentage had their energy expenditure determined by DLW. The mean age of the subjects included in this phase of the study was 66.4 +/- 3.5 years, and ten of the subjects were men. The mean TEE was 2565 +/- 614 and 2154 +/- 339 kcal.day(-1) for men and women, respectively. The Physical Activity Level (PAL) was 1.58 +/- 0.31 and 1.52 +/- 0.22, respectively. Under-reporting of food intake was highly prevalent, with a mean percentage of reported intake in relation to measured TEE of -17.7%. Thus, under-reporting of food intake is highly prevalent among Brazilian independent older persons. The DLW method is an important tool in nutritional studies and its use is to be recommended in developing countries. Copyright (C) 2010 John Wiley & Sons, Ltd.
Resumo:
Objective: To evaluate the percutaneous Achilles tendon sectioning technique using a large gauge needle for the correction of residual equinus of congenital clubfoot treated with the Ponseti method. Methods: Fifty-seven Achilles tendon sections were prospectively evaluated in thirty-nine patients with clubfoot, treated with the Ponseti method between July 2005 and December 2008. The tenotomy was performed percutaneously with a large gauge needle. Ultrasound scan was performed immediately after the section, to ascertain whether the tenotomy was complete, as well as stump separation. Results: There was complete tendon section in all cases, but the need to perform the section maneuver more than once was common, due to the persistence of the residual strands between tendon stumps. The Thompson test and dynamic ultrasound evaluation were able to detect incomplete tenotomies. The mean ultrasound measurement of the tendon gap was 5.70 +/- 2.23 mm. Two patients had abnormal bleeding, which was controlled by digital pressure and did not compromise foot perfusion. Conclusion: Percutaneous Achilles tendon sectioning with a needle proved to be efficient and safe to correct residual equinus of clubfoot treated with the Ponseti technique.
Resumo:
Hydrogen Sulfide (H2S) is an endogenous gas involved in several biological functions, including modulation of nociception. However, the mechanisms involved in such modulation are not fully elucidated. The present Study demonstrated that the pretreatment of mice with PAG, a H2S synthesis inhibitor, reduced LPS-induced mechanical paw hypernociception. This inhibition of hypernociception was associated with the prevention of neutrophil recruitment to the plantar tissue. Conversely, PAG had no effect on LPS-induced production of the hypernociceptive cytokines, TNF-alpha, IL-1 beta and CXCL1/KC and on hypernociception induced by PGE(2), a directly acting hypernociceptive mediator. In contrast with the pro-nociceptive role of endogenous H2S. systemic administration of NaHS, a H2S donor, reduced LPS-induced mechanical hypernociception in mice. Moreover, this treatment inhibited mechanical hypernociception induced by PGE(2), suggesting a direct effect of H2S on nociceptive neurons. The antinociceptive mechanism of exogenous H2S depends on K-(ATP)(+) channels since the inhibition of PGE(2) hypernociception by NaHS was prevented by glibenclamide (K-(ATP)(+) channel blocker). Finally, NaHS did not alter the thermal nociceptive threshold in the hot-plate test, confirming that its effect is mainly peripheral. Taken together, these results suggest that H2S has a dual role in inflammatory hypernociception: 1. an endogenous pro-nociceptive effect due to up-regulation of neutrophil migration. and 2. an antinociceptive effect by direct blockade of nociceptor sensitization modulating K-(ATP)(+) channels. (c) 2008 Elsevier B.V. All rights reserved.
Resumo:
particularly neutrophil chemoattraction. Herein, the role of C5a in the genesis of inflammatory hypernociception was investigated in rats and mice using the specific C5a receptor antagonist PMX53 (AcF-[OP(D-Cha)WR]). Experimental approach: Mechanical hypernociception was evaluated with a modification of the Randall-Selitto test in rats and electronic pressure meter paw test in mice. Cytokines were measured by ELISA and neutrophil migration was determined by myeloperoxidase activity. Key results: Local pretreatment of rats with PMX53 (60-180 mg per paw) inhibited zymosan-, carrageenan-, lipopolysaccharide (LPS)- and antigen-induced hypernociception. These effects were associated with C5a receptor blockade since PMX53 also inhibited the hypernociception induced by zymosan- activated serum and C5a but not by the direct-acting hypernociceptive mediators, prostaglandin E-2 and dopamine. Underlying the C5a hypernociceptive mechanisms, PMX53 did not alter the cytokine release induced by inflammatory stimuli. However, PMX53 inhibited cytokine-induced hypernociception. PMX53 also inhibited the recruitment of neutrophils induced by zymosan but not by carrageenan or LPS, indicating an involvement of neutrophils in the hypernociceptive effect of C5a. Furthermore, the C5a-induced hypernociception was reduced in neutrophil-depleted rats. Extending these findings in rats, blocking C5a receptors also reduced zymosan- induced joint hypernociception in mice. Conclusions and implications: These results suggest that C5a is an important inflammatory hypernociceptive mediator, acting by a mechanism independent of hypernociceptive cytokine release, but dependent on the presence of neutrophils. Therefore, we suggest that inhibiting the action of C5a has therapeutic potential in the control of inflammatory pain.
Resumo:
Tourism has had a profound impact upon destinations worldwide, and although this impact has been positive for many destinations, there are numerous examples where tourism has adversely impacted upon the environment and social fabric of the destination community (Coccossis 1996; Murphy 1985). The negative impacts of tourism have been attributed, among other things, to inadequate or non-existent planning for development (Gunn 1994; Hall2000). This has led to increased calls for tourism planning to offset some of the negative impacts that tourism can have on the destination community. While a number of approaches have been advocated, a collaborative philosophy, based on the principles of sustainability, is more likely to result in acceptable and successful policies and programmes for tourism destinations (Farrell1986; Jamal & Getz 1995; Maitland 2002; Minca & Getz 1995). Such an approach focuses on cooperation and broader based participation in tourism planning and decision-making between stakeholders to lead to agreement on planning directions and goals, with one of the primary objectives of collaborative arrangements being to develop a strategic vision for a destination (Bramwell & Lane 2000). [Extract from introduction]
Resumo:
The mortality and morbidity caused by alcohol, tobacco and illicit drug misuse represents a significant public health burden (Ezzati et al., 2002). A key part of the public health response is the collection of epidemiological and social science data to define at-risk populations to identify opportunities for intervention and to evaluate the effectiveness of policies in preventing or treating drug misuse and drug-related harm. The systematic use of epidemiological and social science research methods to study illicit drug use is barely 40 years old in the United States and United Kingdom, which have pioneered this approach. Because of the sensitive nature of epidemiological research on illicit drug use a unique set of ethical challenges need to be explicitly addressed by the field. Although ethics guidelines have been proposed (Council for International Organizations of Medical Sciences, 1991), scholarship on the ethics of epidemiology is scant, and consensus on core values not yet achieved (Coughlin, 2000).
Resumo:
The objectives of this study were to check music and voice message influence on vital signs and facial expressions of patients with disorders of consciousness and to connect the existence of patient`s responses with the Glasgow Coma Scale or with the Ramsay Sedation Scale. The method was a single-blinded randomized controlled clinical trial with 30 patients, from two intensive care units, being divided into two groups (control and experimental). Their relatives recorded a voice message and chose a song according to the patient`s preference. The patients were submitted to three sessions for three consecutive days. Significant statistical alterations of the vital signs were noted during the message playback (oxygen saturation-Day 1 and Day 3; respiratory frequency-Day 3) and with facial expression, on Day 1, during both music and message. The conclusion was that the voice message was a stronger stimulus than the music.