957 resultados para Bioengineering and regenerative medicine
Resumo:
Two Amerindian populations from the Peruvian Amazon (Yanesha) and from rural lowlands of the Argentinean Gran Chaco (Wichi) were analyzed. They represent two case study of the South American genetic variability. The Yanesha represent a model of population isolated for long-time in the Amazon rainforest, characterized by environmental and altitudinal stratifications. The Wichi represent a model of population living in an area recently colonized by European populations (the Criollos are the population of the admixed descendents), whose aim is to depict the native ancestral gene pool and the degree of admixture, in relation to the very high prevalence of Chagas disease. The methods used for the genotyping are common, concerning the Y chromosome markers (male lineage) and the mitochondrial markers (maternal lineage). The determination of the phylogeographic diagnostic polymorphisms was carried out by the classical techniques of PCR, restriction enzymes, sequencing and specific mini-sequencing. New method for the detection of the protozoa Trypanosoma cruzi was developed by means of the nested PCR. The main results show patterns of genetic stratification in Yanesha forest communities, referable to different migrations at different times, estimated by Bayesian analyses. In particular Yanesha were considered as a population of transition between the Amazon basin and the Andean Cordillera, evaluating the potential migration routes and the separation of clusters of community in relation to different genetic bio-ancestry. As the Wichi, the gene pool analyzed appears clearly differentiated by the admixed sympatric Criollos, due to strict social practices (deeply analyzed with the support of cultural anthropological tools) that have preserved the native identity at a diachronic level. A pattern of distribution of the seropositivity in relation to the different phylogenetic lineages (the adaptation in evolutionary terms) does not appear, neither Amerindian nor European, but in relation to environmental and living conditions of the two distinct subpopulations.
Resumo:
Practice guidelines are systematically developed statements and recommendations that assist the physicians and patients in making decisions about appropriate health care measures for specific clinical circumstances taking into account specific national health care structures. The 1(st) revision of the S-2k guideline of the German Sepsis Society in collaboration with 17 German medical scientific societies and one self-help group provides state-of-the-art information (results of controlled clinical trials and expert knowledge) on the effective and appropriate medical care (prevention, diagnosis, therapy and follow-up care) of critically ill patients with severe sepsis or septic shock. The guideline had been developed according to the "German Instrument for Methodological Guideline Appraisal" of the Association of the Scientific Medical Societies (AWMF). In view of the inevitable advancements in scientific knowledge and technical expertise, revisions, updates and amendments must be periodically initiated. The guideline recommendations may not be applied under all circumstances. It rests with the clinician to decide whether a certain recommendation should be adopted or not, taking into consideration the unique set of clinical facts presented in connection with each individual patient as well as the available resources.
Resumo:
The study was part of a nationwide evaluation of complementary and alternative medicine (CAM) in Swiss primary care. The aim of the study was to compare patient-physician relationships and the respective patient-reported relief of symptoms between CAM and conventional primary care (COM).
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In Switzerland and in the whole western world, the growing popularity of CAM is calling for its implementation in the undergraduate medical curriculum.
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It is becoming most clear that many genes are involved in controlling the regulation of growth. Ultimately however, at the level of growth hormone (GH), the relevant question may be not whether a patient is GH-deficient, but whether he is GH-responsive. As these disturbances can be divided into two gross categories, namely alterations causing subnormal GH secretion and/or those presenting with subnormal GH sensitivity/responsiveness, the main aim of this review is to focus on genes involved in growth regulation leading to short stature caused by an alteration of GH insensitivity/GH responsiveness; in other words, clinical circumstances where individually adapted GH replacement therapy may help to increase height velocity and eventually final height.
Resumo:
Current methods to characterize mesenchymal stem cells (MSCs) are limited to CD marker expression, plastic adherence and their ability to differentiate into adipogenic, osteogenic and chondrogenic precursors. It seems evident that stem cells undergoing differentiation should differ in many aspects, such as morphology and possibly also behaviour; however, such a correlation has not yet been exploited for fate prediction of MSCs. Primary human MSCs from bone marrow were expanded and pelleted to form high-density cultures and were then randomly divided into four groups to differentiate into adipogenic, osteogenic chondrogenic and myogenic progenitor cells. The cells were expanded as heterogeneous and tracked with time-lapse microscopy to record cell shape, using phase-contrast microscopy. The cells were segmented using a custom-made image-processing pipeline. Seven morphological features were extracted for each of the segmented cells. Statistical analysis was performed on the seven-dimensional feature vectors, using a tree-like classification method. Differentiation of cells was monitored with key marker genes and histology. Cells in differentiation media were expressing the key genes for each of the three pathways after 21 days, i.e. adipogenic, osteogenic and chondrogenic, which was also confirmed by histological staining. Time-lapse microscopy data were obtained and contained new evidence that two cell shape features, eccentricity and filopodia (= 'fingers') are highly informative to classify myogenic differentiation from all others. However, no robust classifiers could be identified for the other cell differentiation paths. The results suggest that non-invasive automated time-lapse microscopy could potentially be used to predict the stem cell fate of hMSCs for clinical application, based on morphology for earlier time-points. The classification is challenged by cell density, proliferation and possible unknown donor-specific factors, which affect the performance of morphology-based approaches. Copyright © 2012 John Wiley & Sons, Ltd.
Resumo:
Background. No comprehensive systematic review has been published since 1998 about the frequency with which cancer patients use complementary and alternative medicine (CAM). Methods. MEDLINE, AMED, and Embase databases were searched for surveys published until January 2009. Surveys conducted in Australia, Canada, Europe, New Zealand, and the United States with at least 100 adult cancer patients were included. Detailed information on methods and results was independently extracted by 2 reviewers. Methodological quality was assessed using a criteria list developed according to the STROBE guideline. Exploratory random effects metaanalysis and metaregression were applied. Results. Studies from 18 countries (152; >65 000 cancer patients) were included. Heterogeneity of CAM use was high and to some extent explained by differences in survey methods. The combined prevalence for “current use” of CAM across all studies was 40%. The highest was in the United States and the lowest in Italy and the Netherlands. Metaanalysis suggested an increase in CAM use from an estimated 25% in the 1970s and 1980s to more than 32% in the 1990s and to 49% after 2000. Conclusions. The overall prevalence of CAM use found was lower than often claimed. However, there was some evidence that the use has increased considerably over the past years. Therefore, the health care systems ought to implement clear strategies of how to deal with this. To improve the validity and reporting of future surveys, the authors suggest criteria for methodological quality that should be fulfilled and reporting standards that should be required.
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Mesenchymal stem cell (MSC) therapy is a promising approach for regaining muscle function after trauma. Prior to clinical application, the ideal time of transplantation has to be determined. We investigated the effects of immediate and delayed transplantation. Sprague-Dawley rats received a crush trauma to the left soleus muscle. Treatment groups were transplanted locally with 2 × 10(6) autologous MSCs, either immediately or 7 days after trauma. Saline was used as sham therapy. Contraction force tests and histological analyses were performed 4 weeks after injury. GFP-labelled MSCs were followed after transplantation. The traumatized soleus muscles of the sham group displayed a reduction of twitch forces to 36 ± 17% and of tetanic forces to 29 ± 11% of the non-injured right control side, respectively. Delayed MSC transplantation resulted in a significant improvement of contraction maxima in both stimulation modes (twitch, p = 0.011; tetany, p = 0.014). Immediate transplantation showed a significant increase in twitch forces to 59 ± 17% (p = 0.043). There was no significant difference in contraction forces between muscles treated by immediate and delayed cell transplantation. We were able to identify MSCs in the interstitium of the injured muscles up to 4 weeks after transplantation. Despite the fundamental differences of the local environment, which MSCs encounter after transplantation, similar results could be obtained with respect to functional muscle regeneration. We believe that transplanted MSCs residing in the interstitial compartment evolve their regenerative capabilities through paracrine pathways. Our data suggest a large time window of the therapeutical measures.
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OBJECTIVES: Do structural characteristics of general practitioners (GPs) who practice complementary medicine (CAM) differ from those GPs who do not? Assessed characteristics included experience and professional integration of general practitioners (GPs), workload, medical activities, and personal and technical resources of practices. The investigated CAM disciplines were anthroposophic medicine, homoeopathy, traditional Chinese medicine, neural therapy and herbal medicine. MATERIAL AND METHODS: We designed a cross-sectional study with convenience and stratified samples of GPs providing conventional (COM) and/or complementary primary care in Switzerland. The samples were taken from the database of the Swiss medical association (FMH) and from CAM societies. Data were collected using a postal questionnaire. RESULTS: Of the 650 practitioners who were included in the study, 191 were COM, 167 noncertified CAM and 292 certified CAM physicians. The proportion of females was higher in the population of CAM physicians. Gender-adjusted age did not differ between CAM and COM physicians. Nearly twice as many CAM physicians work part-time. Differences were also seen for the majority of structural characteristics such as qualification of physicians, type of practice, type of staff, and presence of technical equipment. CONCLUSION: The study results show that structural characteristics of primary health care do differ between CAM and COM practitioners. We assumed that the activities of GPs are defined essentially by analyzed structures. The results are to be considered for evaluations in primary health care, particularly when quality of health care is assessed.