923 resultados para Chest


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Objective
We hypothesized that elevating creatine in the maternal diet would reach fetal and placental tissues and improve fetal survival after acute hypoxia at birth.
Study Design
Pregnant spiny mice were fed a control or 5% creatine-supplemented diet from day 20 of gestation (term, approximately 39 days). On days 37-38, intrauterine hypoxia was induced by placement of the isolated uterus in a saline solution bath for 7.5-8 minutes, after which fetuses were expelled from the uterus and resuscitation was attempted by manual palpation of the chest. Total creatine content (creatine + phosphocreatine) of placental, fetal, and maternal organs was measured.
Results
The maternal creatine diet significantly increased total creatine content in the placenta, fetal brain, heart, liver, and kidney and increased the capacity of offspring to survive birth hypoxia. Maternal creatine improved postnatal growth after birth hypoxia.
Conclusion
This study provides evidence that creatine has potential as a prophylactic therapy for pregnancies that are classified as high risk for fetal hypoxia.

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The immunocompetence handicap hypothesis (ICHH) suggests that dominance signals are costly because their development is controlled by testosterone, which is immunosuppressive. Signal control therefore links an increased disease risk with a high quality signal. The chest bib of the house sparrow, Passer domesticus, is a signal known to be related to dominance and under control of testosterone levels. We experimentally manipulated testosterone in male sparrows during the breeding season and again independently during the post-breeding period to test whether variation in levels of testosterone could cause variation in levels of immunocompetence. There was no effect of testosterone manipulation on the cell-mediated response of birds to phytohaemagglutinin injection, nor did testosterone levels appear to affect either white blood cell ratios or red blood cell counts. In contrast, both breeding season and post-breeding season testosterone levels had significant effects upon the humoral response of the birds to sheep red blood cell injections. However, whilst testosterone during the breeding season appeared to act immunosuppressively, the role of post-breeding levels is less clear. In concordance with a previous study, there was an indication that corticosterone is involved in mediating the immunosuppressive effects of testosterone. The strength of the secondary humoral response and the cell-mediated response were negatively related suggesting the possibility of a trade-off between the different arms of the immune system. These results provide some support for the ICHH as a mechanism promoting the evolution of costly badges of status, although the results question whether the immunosuppressive cost can be mediated by testosterone at the time of badge development.

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Fluorescence has so far been found in 52 parrot species when illuminated with ultraviolet-A (UVA) 'black' lamps, and two attempts have been made to determine whether such fluorescence plays any role in sexual signalling. However, the contribution of the reflectance versus fluorescence to the total radiance from feathers, even in the most studied species to date (budgerigars), is unclear. Nor has the plumage of this study species been systematically assessed to determine the distribution of fluorescent patches. We therefore used spectrofluorometry to determine which areas of budgerigars fluoresce and the excitation and emission spectra involved; this is the first time that such a technique has been applied to avian plumage. We found that both the yellow crown and (normally hidden) white downy chest feathers exhibit strong UVA-induced fluorescence, with peak emissions at 527 nm and 436 nm, respectively. Conversely, the bright-green chest and dark-blue tail feathers do not fluoresce. When comparing reflectance spectra (400700 nm) from the yellow crown using illuminants with a proportion of UVA comparable to daylight, and illuminants with all UVA removed, no measurable difference resulting from fluorescence was found. This suggests that under normal daylight the contribution of fluorescence to radiance is probably trivial. Furthermore, these spectra revealed that males had fluorescent crowns with substantially higher reflectance than those of females, in both the UV waveband and at longer wavelengths. Reflectance spectrophotometry was also performed on a number of live wild-type male budgerigars to investigate the chromatic contrast between the different plumage areas. This showed that many plumage regions are highly UV-reflective. Overall our results suggest that rapid surveys using UVA black lamps may overestimate the contribution of fluorescence to plumage coloration, and that any signalling role of fluorescence emissions, at least from the yellow crown of budgerigars, may not be as important as previously thought.

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Introduction. Meeting the needs of migrant groups in Europe requires cross-culturally valid questionnaires, a substantial challenge to researchers. The Rose Angina Questionnaire (RAQ) is an important measure of coronary heart disease prevalence. It consists of seven items that collectively yield a diagnosis of angina. It has been shown to perform inconsistently across some ethnic groups in Britain. This study aimed to assess the need for modifying the RAQ for cross-culturally valid use in the three main ethnic groups in Scotland.

Methods. Interviews were carried out with Pakistani Punjabi speakers (n=26), Chinese Cantonese speakers (n=29) and European-origin English speakers (n=25). Bilingual project workers interviewed participants and provided translation and commentary to the English-speaking researcher. Participants were asked about general and cardiovascular health beliefs and behaviours, and about attitudes to pain and chest pain. They were also asked to comment on their understanding of an existing version of the RAQ in their language.

Results. No dominant themes in the cultural construction of health, pain or cardiovascular knowledge emerged that may significantly influence RAQ response between language groups. Problems were encountered with the Punjabi and Cantonese translations of the RAQ. For example, the translation for “chest” was interpreted by some Pakistani and fewer Chinese women to mean “breasts”. “Walking uphill” was translated in Chinese as “walking the hill”, without stipulation of the direction, so that some Cantonese speakers interpreted the question as meaning walking downhill. In addition, many Chinese interpreted RAQ items to be referring to breathlessness rather than chest pain due to ambiguous wording.

Conclusion. Existing Punjabi and Cantonese versions of the RAQ should be modified before being used in multi-ethnic surveys. Current versions are unlikely to be yielding data that is comparable across groups. Other language versions also require similar investigation to study the cardiovascular health of Europe’s migrant groups.

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Ring species, in which reproductively isolated forms are connected by a chain of intermediate populations, provide valuable insights into the maintenance of trait variability, divergence in sympatry, and the how small changes can lead to species level differences. The parrot Platycercus elegans of eastern Australia is highly variable in plumage coloration in the wild, ranging from pale yellow to deep crimson in the chest, rump and head. It has been suggested as the only known parrot ring species worldwide, and one of less than ~25 ring species amongst all organisms. We test hypotheses for the information signalled by the colour variation, and for the maintenance of the variability.

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Badges of status function in many birds within a social context to establish dominance hierarchies and reduce antagonistic encounters. In order to maintain the honesty of the signalling system, such badges must be costly to produce or to maintain. The chest bib of the house sparrow functions as a badge of status and changes in size are known to be controlled by testosterone levels. We sought to test the relative importance of testosterone as opposed to bib size in determining dominance within a group of male house sparrows. We did this by manipulating testosterone levels independently during both breeding and post-breeding seasons in experimental birds and examining the effect of testosterone titre, as well as corticosterone titre relative to bib size on dominance levels. Dominance hierarchies within the groups were tested during both the breeding and post-breeding phases. We compared the results of these tests with dominance among intact (unmanipulated) birds. Results suggested that the breeding season dominance levels were largely determined by testosterone levels as well as bib size, whereas the post-breeding dominance levels were determined by postbreeding testosterone titre and previous breeding season dominance level. Within unmanipulated birds, basal corticosterone levels were significantly, negatively correlated with dominance level, but only during the breeding season. The influence of breeding season dominance on post-breeding dominance suggests social history is important in determining dominance interactions as well as current testosterone levels and bib size.

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The heart muscle of a cardiac arrest victim continues to accumulate damage throughout its lifetime. This reduces the heart's ability to pump sufficient oxygen and nutrient blood to meet the body's needs. Medical researchers have shown that direct injection of pre-harvested skeletal myoblast cells into the heart can restore some muscle function [1]. This operative procedure usually necessitates the surgeon to open a patient's chest. The open chest procedure is usually a lengthy process and often extends the recovery time of the patient. Alternatively, a high accuracy surgical aid robotic system can be used to assist the thoracoscopic surgery [2][3]. While the robotic surgical method aids faster patient recovery, a less experienced surgeon can potentially cause damage to surrounding tissue.

This paper presents a study into the development of a virtual haptically-enabled heart myoblast injection simulation environment, which can be used to train new surgeons to get hands on experience with the process. The paper also discusses the development of a generic constraint motion technique for needle insertion. Experiments on human performance measures and efficacy, while interacting with haptic feedback training models, are also presented. The experiment involved 10 operators, with each person repeating the needle insertion and injection 10 times. A notable improvement in the task execution time with the number of repetitions was observed. Operators improved their time by up to 300% compared to their first training attempt for a static heart scenario. Under a dynamic heart motion, operator's performance was slightly lower, with the successful rate of completing the experiment reduced from 84% to 75%.

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Context Early pulmonary infection in children with cystic fibrosis leads to increased morbidity and mortality. Despite wide use of oropharyngeal cultures to identify pulmonary infection, concerns remain over their diagnostic accuracy. While bronchoalveolar lavage (BAL) is an alternative diagnostic tool, evidence for its clinical benefit is lacking.

Objective To determine if BAL-directed therapy for pulmonary exacerbations during the first 5 years of life provides better outcomes than current standard practice relying on clinical features and oropharyngeal cultures.

Design, Setting, and Participants The Australasian Cystic Fibrosis Bronchoalveolar Lavage (ACFBAL) randomized controlled trial, recruiting infants diagnosed with cystic fibrosis through newborn screening programs in 8 Australasian cystic fibrosis centers. Recruitment occurred between June 1, 1999, and April 30, 2005, with the study ending on December 31, 2009.

Interventions BAL-directed (n=84) or standard (n=86) therapy until age 5 years. The BAL-directed therapy group underwent BAL before age 6 months when well, when hospitalized for pulmonary exacerbations, if Pseudomonas aeruginosa was detected in oropharyngeal specimens, and after P aeruginosa eradication therapy. Treatment was prescribed according to BAL or oropharyngeal culture results.

Main Outcome Measures Primary outcomes at age 5 years were prevalence of P aeruginosa on BAL cultures and total cystic fibrosis computed tomography (CF-CT) score (as a percentage of the maximum score) on high-resolution chest CT scan.

Results Of 267 infants diagnosed with cystic fibrosis following newborn screening, 170 were enrolled and randomized, and 157 completed the study. At age 5 years, 8 of 79 children (10%) in the BAL-directed therapy group and 9 of 76 (12%) in the standard therapy group had P aeruginosa in final BAL cultures (risk difference, −1.7% [95% confidence interval, −11.6% to 8.1%]; P=.73). Mean total CF-CT scores for the BAL-directed therapy and standard therapy groups were 3.0% and 2.8%, respectively (mean difference, 0.19% [95% confidence interval, −0.94% to 1.33%]; P=.74).

Conclusion Among infants diagnosed with cystic fibrosis, BAL-directed therapy did not result in a lower prevalence of P aeruginosa infection or lower total CF-CT score when compared with standard therapy at age 5 years.

Trial Registration anzctr.org.au Identifier: ACTRN12605000665639

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Objectives. The Rose Angina Questionnaire (RAQ) is an important measure of coronary heart disease prevalence. It has been shown to perform inconsistently across some ethnic groups in Britain. This study investigates whether the best available versions of the RAQ in Punjabi and Cantonese were linguistically equivalent to the English version.

Design. Interviews were carried out with lay people from the Pakistani, Chinese and European-origin communities in Scotland to assess the versions of the RAQ used in the Newcastle Heart Project (the best available versions). For each questionnaire item, participants were asked to elaborate on their understanding of the question and the meaning of keywords or phrases.

Results. Problems were discovered with the Punjabi and Cantonese translations of the RAQ. For example, the translation for ‘chest’ was interpreted by some Pakistani and Chinese women to mean ‘breasts’. ‘Walking uphill’ was translated in Chinese as ‘walking the hill’, without stipulation of the direction, so that some Cantonese speakers interpreted the question as pertaining to walking downhill. Many Chinese interpreted RAQ items to be referring to breathlessness rather than chest pain due to ambiguous wording.

Conclusion. Existing versions of the RAQ are unlikely to be yielding data that are cross-culturally valid or comparable. For robust health survey research in languages other than that in which the questionnaire was developed, lay assessment of questionnaires prior to and after translation is a necessity rather than a luxury.

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Background Newborn screening allows novel treatments for cystic fibrosis (CF) to be trialled in early childhood before irreversible lung injury occurs. As respiratory exacerbations are a potential trial outcome variable, we determined their rate, duration and clinical features in preschool children with CF; and whether they were associated with growth, lung structure and function at age 5 years. Methods: Respiratory exacerbations were recorded prospectively in Australasian CF Bronchoalveolar Lavage trial subjects from enrolment after newborn screening to age 5 years, when all participants underwent clinical assessment, chest CT scans and spirometry. Results 168 children (88 boys) experienced 2080 exacerbations, at an average rate of 3.66 exacerbations per person-year; 80.1% were community managed and 19.9% required hospital admission. There was an average increase in exacerbation rate of 9% (95% CI 4% to 14%; p<0.001) per year of age. Exacerbation rate differed by site (p<0.001) and was 26% lower (95% CI 12% to 38%) in children receiving 12 months of prophylactic antibiotics. The rate of exacerbations in the first 2 years was associated with reduced forced expiratory volume in 1 s z scores. Ever having a hospitalmanaged exacerbation was associated with bronchiectasis (OR 2.67, 95% CI 1.13 to 6.31) in chest CT scans, and lower weight z scores at 5 years of age (coefficient -0.39, 95% CI -0.74 to -0.05). Conclusions Respiratory exacerbations in young children are markers for progressive CF lung disease and are potential trial outcome measures for novel treatments in this age group.

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Aims and objectives: To examine nursing students' and registered nurses' teamwork skills whilst managing simulated deteriorating patients. Background: Studies continue to show the lack of timely recognition of patient deterioration. Management of deteriorating patients can be influenced by education and experience. Design: Mixed methods study conducted in two universities and a rural hospital in Victoria, and one university in Queensland, Australia. Methods: Three simulation scenarios (chest pain, hypovolaemic shock and respiratory distress) were completed in teams of three by 97 nursing students and 44 registered nurses, equating to a total of 32 student and 15 registered nurse teams. Data were obtained from (1) Objective Structured Clinical Examination rating to assess performance; (2) Team Emergency Assessment Measure scores to assess teamwork; (3) simulation video footage; (4) reflective interview during participants' review of video footage. Qualitative thematic analysis of video and interview data was undertaken. Results: Objective structured clinical examination performance was similar across registered nurses and students (mean 54% and 49%); however, Team Emergency Assessment Measure scores differed significantly between the two groups (57% vs 38%, t = 6·841, p < 0·01). In both groups, there was a correlation between technical (Objective Structured Clinical Examination) and nontechnical (Team Emergency Assessment Measure) scores for the respiratory distress scenario (student teams: r = 0·530, p = 0·004, registered nurse teams r = 0·903, p < 0·01) and hypovolaemia scenario (student teams: r = 0·534, p = 0·02, registered nurse teams: r = 0·535, p = 0·049). Themes generated from the analysis of the combined quantitative and qualitative data were as follows: (1) leadership and followership behaviours; (2) help-seeking behaviours; (3) reliance on previous experience; (4) fixation on a single detail; and (5) team support. Conclusions: There is scope to improve leadership, team work and task management skills for registered nurses and nursing students. Simulation appears to be beneficial in enabling less experienced staff to assess their teamwork skills. Relevance to clinical practice: There is a need to encourage less experienced staff to become leaders and for all staff to develop improved teamwork skills for medical emergencies. © 2014 John Wiley & Sons Ltd.

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To develop a mathematical model to predict the probability of having community-acquired pneumonia and to evaluate an already developed prediction rule that has not been validated in a clinical scenario.

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 This paper presents an evaluation of microwave Doppler radar in capturing the respiration signal from the chest and abdomen simultaneously using two radar systems. Two experiments were conducted to investigate the feasibility of using Doppler radar in measuring respiration from both chest and abdomen simultaneously. Results obtained indicate that the respiration patterns from the radar were highly correlated with the reference respiration strap readings for normal breathing scenarios and also sensitive enough in capturing the paradoxical movement between the chest and the abdomen in the professionally role played experiments.

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Aims and objectives: To examine nursing students' and registered nurses' teamwork skills whilst managing simulated deteriorating patients. Background: Studies continue to show the lack of timely recognition of patient deterioration. Management of deteriorating patients can be influenced by education and experience. Design: Mixed methods study conducted in two universities and a rural hospital in Victoria, and one university in Queensland, Australia. Methods: Three simulation scenarios (chest pain, hypovolaemic shock and respiratory distress) were completed in teams of three by 97 nursing students and 44 registered nurses, equating to a total of 32 student and 15 registered nurse teams. Data were obtained from (1) Objective Structured Clinical Examination rating to assess performance; (2) Team Emergency Assessment Measure scores to assess teamwork; (3) simulation video footage; (4) reflective interview during participants' review of video footage. Qualitative thematic analysis of video and interview data was undertaken. Results: Objective structured clinical examination performance was similar across registered nurses and students (mean 54% and 49%); however, Team Emergency Assessment Measure scores differed significantly between the two groups (57% vs 38%, t = 6·841, p < 0·01). In both groups, there was a correlation between technical (Objective Structured Clinical Examination) and nontechnical (Team Emergency Assessment Measure) scores for the respiratory distress scenario (student teams: r = 0·530, p = 0·004, registered nurse teams r = 0·903, p < 0·01) and hypovolaemia scenario (student teams: r = 0·534, p = 0·02, registered nurse teams: r = 0·535, p = 0·049). Themes generated from the analysis of the combined quantitative and qualitative data were as follows: (1) leadership and followership behaviours; (2) help-seeking behaviours; (3) reliance on previous experience; (4) fixation on a single detail; and (5) team support. Conclusions: There is scope to improve leadership, team work and task management skills for registered nurses and nursing students. Simulation appears to be beneficial in enabling less experienced staff to assess their teamwork skills. Relevance to clinical practice: There is a need to encourage less experienced staff to become leaders and for all staff to develop improved teamwork skills for medical emergencies.