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Infections caused by Edwardsiella ictaluri are one of the biggest problems in the catfish industry in North America and have been reported in fishes around the world. E. ictaluri was detected in juvenile pintado Pseudoplatystoma corruscans-a Brazilian catfish-in a farm in Paraná State, Brazil; diseased animals showed ascites and neurological signs of infection, with more than 50% mortality. Exotic invasive species susceptible to this bacterium have been reported in this area. We assessed the susceptibility of pintado to E. ictaluri with experimental infection via intraperitoneal and immersion methods as well as a cohabitation experiment with Nile tilapia Oreochromis niloticus and African walking catfish Clarias gariepinus, 2 exotic invasive species. All pintados challenged by intraperitoneal and immersion routes and those cohabiting with infected C. gariepinus died within 17 d of the challenge. Mortality of Nile tilapia reached 71.42% after the intraperitoneal and 35.71% in the immersion challenges within 28 d, whereas African walking catfish showed zero mortality. Observed clinical signs were comparable to those in the farm and those described in the literature as enteric septicemia of catfish. With this study, we demonstrated the susceptibility of P. corruscans to E. ictaluri, as well as interspecies transmission of this bacterium.

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Effective management of cardiogenic shock (CS) is hampered by a lack of evidence-based information. This is a high-mortality condition, without clear, evidence-based guidelines for perioperative management, specifically-a lack of target endpoints for treatment (e.g.: mean arterial pressure or oxygenation), utility of regional care systems or the benefits of palliative care. The Acute Cardiovascular Care Association (ACCA) of the European Society of Cardiology (ESC) recently published a position statement that aimed to offer contemporary guidance on the diagnosis and treatment of acute myocardial infarction (AMI) complicated by CS. Herein, we review this complex clinical topic and review the ACCA statement on AMI associated with CS, with a focus on relevance to perioperative management.

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Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease whose pathophysiology is poorly understood. Aiming to better understand the cause of motor neuron death, the use of experimental cell-based models increased significantly over the past years. In this scenario, much knowledge has been generated from the study of motor neurons derived from embryonic stem cells and induced pluripotent stem cells. These methods, however, have advantages and disadvantages, which must be balanced on experimental design. Preclinical studies provide valuable information, making it possible to combine diverse methods to build an expanded knowledge of ALS pathophysiology. In addition to using stem cells as experimental models for understanding disease mechanism, these cells had been quoted for therapy in ALS. Despite ethical issues involved in its use, cell therapy with neural stem cells stands out. A phase I clinical trial was recently completed and a phase II is on its way, attesting the method's safety. In another approach, mesenchymal stromal cells capable of releasing neuroregulatory and anti-inflammatory factors have also been listed as candidates for cell therapy for ALS, and have been admitted as safe in a phase I trial. Despite recent advances, application of stem cells as an actual therapy for ALS patients is still in debate. Here, we discuss how stem cells have been useful in modeling ALS and address critical topics concerning their therapeutic use, such as administration protocols, injection site, cell type to be administered, type of transplantation (autologous vs. allogeneic) among other issues with particular implications for ALS therapy.

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Liver sinusoid endothelial cells (LSEC) constitute an in vitro and in vivo microenvironment for the proliferation and differentiation of hematopoietic stem cells (HSC). Previously, we have shown that LSEC support the survival and growth of murine embryonic stem cells (ESC). In this study, we investigated the capacity of LSEC to promote hematopoietic differentiation from the murine ESC cell line, CGR8. Undifferentiated ESC were cultured on LSEC monolayers in the absence of exogenous cytokines. After 10 and 20 days, cells were harvested and examined by their morphology, phenotype and capacity of hematopoietic colony formation. Microscopic observation of LSEC/ESC cocultures showed the presence of cobblestone areas formation, which indicates active hematopoiesis. Morphological analysis of cell from these foci showed the presence of hematopoietic cells at different stages of differentiation. Cells expressing B lymphoid markers (B220 and CD19) were detected by flow cytometry, and clonogenic assays showed the formation of CFU-pre B colonies. Similar results were observed when ESC were cultured with LSEC conditioned media. Myeloid precursors were also detected by the presence of CFU-GM colonies and cells expressing myeloid markers. These results indicate that LSEC provided an in vitro microenvironment mainly for B cell development, but also myeloid differentiation from ESC. Coculture of ESC with LSEC may constitute a very powerful tool to study the mechanisms involved in B cell generation from ESC.

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BACKGROUND: Approximately 27% of Americans today are obese, and this condition increases the prevalence of metabolic syndrome and diabetes. The UK Prospective Diabetes Study suggests that loss of beta cell function can begin at least 10 years before diagnosis, and mean beta cell function is already less than 50% at diagnosis. The aim of this research was to assess the possibility of detecting loss of beta cell function in obese patients by a novel approach involving nitric oxide assessment using a combination of technologies. MATERIALS AND METHODS: One hundred and fifteen obese patients (93 women, 22 men) of mean age 39 (range 17-62) years, who were candidates for bariatric surgery were included in the study, and underwent laboratory tests, including fasting blood glucose, fasting insulin plasma, and examination with the Electro Sensor complex. The Electro Sensor complex offers a new way to assess nitric oxide production using five technologies managed by software, ie, the galvanic skin response, photoelectrical plethysmography, heart rate variability analysis, bioimpedance analysis, and blood pressure oscillometric measurements. The homeostasis model assessment 2% beta cell function (HOMA2% ß) algorithm was calculated from fasting blood glucose and fasting insulin plasma using free software provided by The University of Oxford Diabetes Trial Unit. The Electro Sensor complex percent beta (ESC% ß) algorithm was calculated from the Electro Sensor complex data and statistical neural network. Statistical analysis was performed to correlate ESC% ß and HOMA2% ß using the coefficient of correlation and Spearman's coefficient of rank correlation. Receiver-operating characteristic curves were also constructed to determine the specificity and sensitivity of ESC% ß in detecting a HOMA2% ß value < 100. RESULTS: The coefficient of correlation between ESC% ß and HOMA2% ß was 0.72 (using log values) and the Spearman's coefficient of rank correlation (rho) was 0.799 (P < 0.0001). ESC% ß had a sensitivity of 77.14% and specificity of 78.21% (cutoff ≤ 157, corresponding to 40% after conversion into a 0%-100% scale) to detect a HOMA2% ß value < 100 (P < 0.0001). CONCLUSION: The ESC% ß algorithm has a high predictive correlation with HOMA2% ß, and good specificity and sensitivity to detect a HOMA2% ß value < 100. Therefore, the Electro Sensor complex enabling nitric oxide assessment represents a novel method of screening for beta cell function in the obese population on a large scale. Such a tool, which is easy to administer, noninvasive, and cost-effective, would be of great benefit for widespread screening of beta cell function in obese patients.

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Background: The ability to create tissues using pluripotent stem cells to repair or replace tissue lost due to damage, i.e. regenerative medicine, is developing very rapidly in many fields of human medicine. For veterinarians, regenerative medicine has focused mainly in the use of stem cells for arthritis and tendon ligament repair, indicating a need for treating musculoskeletal injuries. Our objective is to review the available approaches being used to derive pluripotent stem cells and discuss their potential use for regenerative medicine in the horse. Review: Adult adipose- and bone marrow-derived mesenchymal stem cells (MSC) are being used in practice to treat injuries in horses. However, there is scarce scientific evidence of their effectiveness and little is known of the mechanisms by which such cell preparations improve the healing process. For instance, although early healing response of articular cartilage injury was improved by treatment with injection of MSC, they did not enhance the long-term tissue response, indicating that cell proliferation was attenuated. Better protocols for the isolation and clinical testing of equine MSC are required to confirm healing properties. In contrast to MSC, embryonic stem cells (ESC) derived from the inner-cell- mass (ICM) of blastocyst stage embryos carry the ability to proliferate indefinitely in vitro and, given appropriate and favorable conditions, can differentiate into any tissue in the body. Parthenogenesis (PG) and somatic cell nuclear transfer (SCNT) are used to obtain a genetic match to the host animal and, thereby, eliminate the risk of inducing immune rejection of the grafted tissue. However, apart from the typical markers of pluripotency, equine ESC also express markers of trophoblastic tissues, indicating that they are different and possibly less able to differentiate than the ESC lines obtained in other species. Consequently, further studies are underway to identify conditions to obtain fully pluripotent ESC lines from equine SCNT embryos. To overcome the limitations of ESC lines derived from equine embryos, induced pluripotent stem cells (iPSC) were derived using a piggyBac transposon-based method to deliver transgenes containing the reprogramming factors Oct4, Sox2, Klf4 and c-Myc, expressed in a temporally controlled fashion. Our established fetal-derived iPSC lines express hallmark pluripotency markers, display a stable karyotype after prolonged culture, and are able to form teratomas in immunodeficient mice containing tissues from all three embryonic layers. By establishing a protocol for deriving stable iPSC lines in the horse, we expect that new opportunities will be shortly developed for regenerative therapies in this species. Conclusion: It is possible to derive autologous pluripotent stem cells in horses by using both ESC and iPSC-derived approaches. Although ESC lines are generally the gold standard of pluripotency, further research is required to improve the proliferative and pluripotency characteristics for clinical applications. On the other hand, equine iPSC show excellent stability during prolonged in vitro culture and have the capacity to differentiate into the three germ layers in vivo, suggesting that they could soon be used in pre-clinical trials. Therefore, further studies need to be performed to establish reliable protocols for assessing the regenerative properties of iPS and ESC for equine muscle-skeletal injuries.

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Esse artigo defende que os esforços para expandir a justiciabilidade dos direitos econômicos, sociais e culturais (ESC), perante tribunais supranacionais, possivelmente não venha a ser sempre a melhor forma para aumentar concretamente o respeito a esses direitos. No Sistema Interamericano, os autores deste artigo afirmam que os advogados de direitos humanos serão mais capazes de promover a justiça social e os direitos ESC quando usarem a litigância supranacional como uma ferramenta subsidiária, destinada a apoiar esforços de mobilização já promovidos por movimentos sociais internos. Esse papel coadjuvante pode com freqüência implicar, como uma medida estratégica, a litigância de casos relacionados a direitos ESC dentro da estrutura própria das violações a direitos civis e políticos.

This article contends that efforts to expand the justiciability of economic, social, and cultural (ESC) rights before supranational tribunals may not always be the best way to increase respect for these rights on the ground. In the Inter-American System, the authors maintain that human rights lawyers will best advance social justice and ESC rights when they use supranational litigation as a subsidiary tool to support advocacy efforts led by domestic social movements, a role that may often entail litigating ESC claims strategically within the framework of civil and political violations.

Este artículo sostiene que el esfuerzo por expandir la justiciabilidad de los derechos económicos, sociales y culturales (DESC) ante tribunales internacionales no siempre puede ser la vía más adecuada para mejorar el respeto efectivo de estos derechos. En el sistema interamericano, según los autores, los abogados de derechos humanos lograrán más avances en materia de justicia social y de DESC cuando utilicen el litigio internacional como una herramienta subsidiaria para apoyar esfuerzos de incidencia sostenidos por movimientos sociales locales, una función que a veces puede requerir plantear violaciones de DESC con la perspectiva de violaciones a derechos civiles y políticos.