228 resultados para Chad


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Amniotic fluid cells (AFCs) have been proposed as a valuable source for tissue engineering and regenerative medicine. However, before clinical implementation, rigorous evaluation of this cell source in clinically relevant animal models accepted by regulatory authorities is indispensable. Today, the ovine model represents one of the most accepted preclinical animal models, in particular for cardiovascular applications. Here, we investigate the isolation and use of autologous ovine AFCs as cell source for cardiovascular tissue engineering applications. Fetal fluids were aspirated in vivo from pregnant ewes (n = 9) and from explanted uteri post mortem at different gestational ages (n = 91). Amniotic non-allantoic fluid nature was evaluated biochemically and in vivo samples were compared with post mortem reference samples. Isolated cells revealed an immunohistochemical phenotype similar to ovine bone marrow-derived mesenchymal stem cells (MSCs) and showed expression of stem cell factors described for embryonic stem cells, such as NANOG and STAT-3. Isolated ovine amniotic fluid-derived MSCs were screened for numeric chromosomal aberrations and successfully differentiated into several mesodermal phenotypes. Myofibroblastic ovine AFC lineages were then successfully used for the in vitro fabrication of small- and large-diameter tissue-engineered vascular grafts (n = 10) and cardiovascular patches (n = 34), laying the foundation for the use of this relevant pre-clinical in vivo assessment model for future amniotic fluid cell-based therapeutic applications. Copyright © 2013 John Wiley & Sons, Ltd.

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This article synthesizes findings from a review of the state of research on sustainable land management in Kyrgyzstan and Tajikistan and from an analysis of the interface between research and action. Using the Global Land Project (GLP 2005) analytical framework, we analyzed the distribution of 131 selected publications (including a clearly defined set of local and international academic and gray literature) across the framework's components and links in a social–ecological system. There is a strong emphasis in the literature on the impact of changes in land use and management on ecosystems; however, there is little research on the implications for ecosystem services. This finding is opposed to that of a similar analysis of publications at the global scale (Björnsen Gurung et al 2012). Another major gap was the lack of research on Kyrgyzstan and Tajikistan regarding the influence of global factors on social and ecological systems, despite social, economic, and political integration into global structures since the collapse of the Soviet Union and the increasing influence of climate change. Our analysis disaggregated academic literature published in the region and international academic literature, revealing stark differences. These differences are partly attributable to the legacy of the late Soviet era principle of “rational use of land resources,” which fit the planned economy but lacks approaches for decentralized resource governance. Finally, the emphasis of research on systems knowledge, the lack of transdisciplinary research, and the critical feedback of stakeholders at a regional sustainable land management forum suggest that actionable sustainable land management research on Kyrgyzstan and Tajikistan is rare. Recommendations are made for targeted, application-focused, multistakeholder research and knowledge sharing, including local and international researchers as well as practitioners, policy-makers, and land users.

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Greetings from Dean Patricia Starck New DNP program explores new frontiers of nursing Profile Joanne V. Hickey, PhD, APRN, BC, ACNP, FAAN, FCCM With assistance from PARTNERS scholarship, Family Practice Nurse pursues her dream through new DNP program School of Nursing offers training in geriatrics for nurses PARTNERS organization endows first professorship University of Texas Health Services planning to expand number of clinics Caring Leaders The Engine of Innovation: School of Nursing researchers part of $36 million NIH grant to spur innovation Johnson and Johnson gala spotlights nurses Chad and Heath LePray UT School of Nursing and Memorial Hermann Hospital create partnership with Chief of Advanced Practice position A Tribute to Frank Cole Faculty Scholarship Endowed Faculty Positions

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The immunosuppressive drugs cyclosporine A (CsA) and tacrolimus (FK506), also called calcineurin inhibitors, have truly revolutionized allograft transplantation. The introduction of CsA in 1976 was the first major advance in transplantation since the introduction of prednisone and azathioprine made allograft transplantation possible in the early 1950s and 1960s. FK506 was approved in 1994 and led to dramatic improvements in solid organ transplantation, allowing highly antigenic lymph node bearing allografts, such as the small bowel, to be transplanted. Recently, FK506 monotherapy has successfully allowed combined small bowel and partial abdominal wall transplantation in humans. The success of FK506 and CsA has made them key drugs in the modern era of transplantation. The purine synthesis inhibitor mycophenolate mofetil (MMF) was approved in 1995, and the drug Sirolimus (rapamycin) was introduced in 1999. Combining these drugs with calcineurin inhibitors has significantly reduced the incidence of acute rejection and improved solid organ allograft survival, with a reduction in adverse effects.

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BACKGROUND Clinical prognostic groupings for localised prostate cancers are imprecise, with 30-50% of patients recurring after image-guided radiotherapy or radical prostatectomy. We aimed to test combined genomic and microenvironmental indices in prostate cancer to improve risk stratification and complement clinical prognostic factors. METHODS We used DNA-based indices alone or in combination with intra-prostatic hypoxia measurements to develop four prognostic indices in 126 low-risk to intermediate-risk patients (Toronto cohort) who will receive image-guided radiotherapy. We validated these indices in two independent cohorts of 154 (Memorial Sloan Kettering Cancer Center cohort [MSKCC] cohort) and 117 (Cambridge cohort) radical prostatectomy specimens from low-risk to high-risk patients. We applied unsupervised and supervised machine learning techniques to the copy-number profiles of 126 pre-image-guided radiotherapy diagnostic biopsies to develop prognostic signatures. Our primary endpoint was the development of a set of prognostic measures capable of stratifying patients for risk of biochemical relapse 5 years after primary treatment. FINDINGS Biochemical relapse was associated with indices of tumour hypoxia, genomic instability, and genomic subtypes based on multivariate analyses. We identified four genomic subtypes for prostate cancer, which had different 5-year biochemical relapse-free survival. Genomic instability is prognostic for relapse in both image-guided radiotherapy (multivariate analysis hazard ratio [HR] 4·5 [95% CI 2·1-9·8]; p=0·00013; area under the receiver operator curve [AUC] 0·70 [95% CI 0·65-0·76]) and radical prostatectomy (4·0 [1·6-9·7]; p=0·0024; AUC 0·57 [0·52-0·61]) patients with prostate cancer, and its effect is magnified by intratumoral hypoxia (3·8 [1·2-12]; p=0·019; AUC 0·67 [0·61-0·73]). A novel 100-loci DNA signature accurately classified treatment outcome in the MSKCC low-risk to intermediate-risk cohort (multivariate analysis HR 6·1 [95% CI 2·0-19]; p=0·0015; AUC 0·74 [95% CI 0·65-0·83]). In the independent MSKCC and Cambridge cohorts, this signature identified low-risk to high-risk patients who were most likely to fail treatment within 18 months (combined cohorts multivariate analysis HR 2·9 [95% CI 1·4-6·0]; p=0·0039; AUC 0·68 [95% CI 0·63-0·73]), and was better at predicting biochemical relapse than 23 previously published RNA signatures. INTERPRETATION This is the first study of cancer outcome to integrate DNA-based and microenvironment-based failure indices to predict patient outcome. Patients exhibiting these aggressive features after biopsy should be entered into treatment intensification trials. FUNDING Movember Foundation, Prostate Cancer Canada, Ontario Institute for Cancer Research, Canadian Institute for Health Research, NIHR Cambridge Biomedical Research Centre, The University of Cambridge, Cancer Research UK, Cambridge Cancer Charity, Prostate Cancer UK, Hutchison Whampoa Limited, Terry Fox Research Institute, Princess Margaret Cancer Centre Foundation, PMH-Radiation Medicine Program Academic Enrichment Fund, Motorcycle Ride for Dad (Durham), Canadian Cancer Society.

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OBJECTIVE A number of factors limit the effectiveness of current aortic arch studies in assessing optimal neuroprotection strategies, including insufficient patient numbers, heterogenous definitions of clinical variables, multiple technical strategies, inadequate reporting of surgical outcomes and a lack of collaborative effort. We have formed an international coalition of centres to provide more robust investigations into this topic. METHODS High-volume aortic arch centres were identified from the literature and contacted for recruitment. A Research Steering Committee of expert arch surgeons was convened to oversee the direction of the research. RESULTS The International Aortic Arch Surgery Study Group has been formed by 41 arch surgeons from 10 countries to better evaluate patient outcomes after aortic arch surgery. Several projects, including the establishment of a multi-institutional retrospective database, randomized controlled trials and a prospectively collected database, are currently underway. CONCLUSIONS Such a collaborative effort will herald a turning point in the surgical management of aortic arch pathologies and will provide better powered analyses to assess the impact of varying surgical techniques on mortality and morbidity, identify predictors for neurological and operative risk, formulate and validate risk predictor models and review long-term survival outcomes and quality-of-life after arch surgery.

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Whereas whole first-milked colostrum IgG1 variation is documented, the IgG1 difference between the quarter mammary glands of dairy animals is unknown. First colostrum was quarter-collected from healthy udders of 8 multiparous dairy cows, all within 3h of parturition. Weight of colostrum produced by individual quarters was determined and a sample of each was frozen for subsequent analysis. Immunoglobulin G1 concentration (mg/mL) was measured by ELISA and total mass (g) was calculated. Standard addition method was used to overcome colostrum matrix effects and validate the standard ELISA measures. Analysis of the data showed that cow and quarter (cow) were significantly different in both concentration and total mass per quarter. Analysis of the mean IgG1 concentration of the front and rear quarters showed that this was not different, but the large variation in individual quarters confounds the analysis. This quarter difference finding indicates that each mammary gland develops a different capacity to accumulate precolostrum IgG1, whereas the circulating hormone concentrations that induce colostrogenesis reach the 4 glands similarly. This finding also shows that the variation in quarter colostrum production is a contributor to the vast variation in first milking colostrum IgG1 content. Finally, the data suggests other factors, such as locally acting autocrine or paracrine, epigenetic, or stochasticity, in gene regulation mechanisms may impinge on colostrogenesis capacity.

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International agencies and programmes introduced sustainable land management (SLM) to Central Asia after the former Soviet Republics became independent in 1991. An aim of early SLM initiatives was to address challenges linked to the transformation of the agricultural sector from a centrally planned economy to a decentralized market economy. This article analyses the knowledge–action interface in Kyrgyzstan and Tajikistan as it relates to SLM. The analysis focuses on the influence of underlying land management concepts by means of a literature review. Contemporary barriers at the research–action interface were identified using participatory appraisal. And a historically contextualized understanding of the effectiveness of interactions between researchers, policy makers and practitioners is based on an analysis of purposefully selected cases. The study concludes that knowledge of different stakeholder groups is often highly disconnected. Interdisciplinary and transdisciplinary studies are rare, and academic research on SLM has subsequently been ineffective at contributing to substantial benefits for society. Further, researchers, policy makers and practitioners in this context must recognize the differences between SLM and what is often referred to as the equivalent Soviet-era concept—rational use of land resources—and the resulting implications of these differences. The authors recommend the following: creating an enabling environment for SLM research through academic institutional reform removing structural constraints, making research outcomes more effective by applying systems approaches that produce evidence for policy makers on the multiple benefits of SLM, helping land users evaluate SLM strategies and investing in the establishment and maintenance of a multi-stakeholder SLM platform that allows dynamic exchange.

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Pem, a member of the PEPP homeobox family, is expressed in somatic cells in male and female reproductive tissues. In the adult murine testis, Pem is specifically expressed in Sertoli cells, where it is restricted to stages IV–VIII of the seminiferous epithelial cycle. To identify Pem's function in Sertoli cells, transgenic mice were generated that express Pem in Sertoli cells during all stages of the seminiferous epithelial cycle. This resulted in an increase in double-strand DNA breaks in preleptotene spermatocytes and single-strand DNA breaks in elongating spermatids. My results suggest that Pem regulates Sertoli-cell genes that encode secreted or cell-surface proteins that serve to control premeiotic DNA replication, DNA repair, and/or chromatin remodeling in the adjacent germ cells. Three additional transgenic mouse containing varying lengths of the Pem male-specific promoter (Pp) were generated to identify the sequences responsible for regulating Pem expression in the testis and epididymis. My analysis suggests that there are at least two regulatory regions in the Pem Pp. In the testis, region II directs androgen-dependent expression specifically in Sertoli cells whereas region I fine-tunes stage-specific expression by acting as a negative regulator. In the epididymis, region II confers androgen-dependent, developmentally-regulated expression in the caput whereas region I prevents inappropriate expression in the corpus. I also report the identification and characterization of two human PEPP family members related to Pem that I have named hPEPP1 and hPEPP2. The hPEPP1 and hPEPP2 homeodomains are more closely related to PEPP subfamily homeodomains than to any other homeodomain subfamily. Both genes are localized to the specific region of the human X chromosome that shares synteny with the region on the murine X chromosome containing three PEPP homeobox genes, Pem, Psx-1, and Psx-2. hPEPP1 and hPEPP2 mRNA expression is restricted to the testis but is aberrantly expressed in tumor cells of different origins, analogous to the expression pattern of Pem but not of Psx-1 or Psx-2. Unlike all known PEPP members, neither hPEPP1 nor hPEPP2 are expressed in placenta, which suggests that the regulation of the PEPP family has undergone significant alteration since the split between hominids and rodents. ^

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During the healthcare reform debate in the United States in 2009/2010, many health policy experts expressed a concern that expanding coverage would increase waiting times for patients to obtain care. Many complained that delays in obtaining care in turn would compromise the quality of healthcare in the United States. Using data from The Commonwealth Fund 2010 International Health Policy Survey in Eleven Countries, this study explored the relationship between wait times and quality of care, employing a wait time scale and several quality of care indicators present in the dataset. The impact of wait times on quality was assessed. Increased wait time was expected to reduce quality of care. However, this study found that wait times correlated with better health outcomes for some measures, and had no association with others. Since this is a pilot study and statistical significance was not achieved for any of the correlations, further research is needed to confirm and deepen the findings. However, if future studies confirm this finding, an emphasis on reducing wait times at the expense of other health system level performance variables may be inappropriate. ^

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High-resolution, small-bore PET systems suffer from a tradeoff between system sensitivity, and image quality degradation. In these systems long crystals allow mispositioning of the line of response due to parallax error and this mispositioning causes resolution blurring, but long crystals are necessary for high system sensitivity. One means to allow long crystals without introducing parallax errors is to determine the depth of interaction (DOI) of the gamma ray interaction within the detector module. While DOI has been investigated previously, newly available solid state photomultipliers (SSPMs) well-suited to PET applications and allow new modules for investigation. Depth of interaction in full modules is a relatively new field, and so even if high performance DOI capable modules were available, the appropriate means to characterize and calibrate the modules are not. This work presents an investigation of DOI capable arrays and techniques for characterizing and calibrating those modules. The methods introduced here accurately and reliably characterize and calibrate energy, timing, and event interaction positioning. Additionally presented is a characterization of the spatial resolution of DOI capable modules and a measurement of DOI effects for different angles between detector modules. These arrays have been built into a prototype PET system that delivers better than 2.0 mm resolution with a single-sided-stopping-power in excess of 95% for 511 keV g's. The noise properties of SSPMs scale with the active area of the detector face, and so the best signal-to-noise ratio is possible with parallel readout of each SSPM photodetector pixel rather than multiplexing signals together. This work additionally investigates several algorithms for improving timing performance using timing information from multiple SSPM pixels when light is distributed among several photodetectors.

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We examined near-surface, late Holocene deep-sea sediments at nine sites on a north-south transect from the Congo Fan (4°S) to the Cape Basin (30°S) along the Southwest African continental margin. Contents, distribution patterns and molecular stable carbon isotope signatures of long-chain n-alkanes (C27-C33) and n-alkanols (C22-C32) are indicators of land plant vegetation of different biosynthetic types, which can be correlated with concentrations and distributions of pollen taxa in the same sediments. Calculated clusters of wind trajectories and satellite Aerosol Index imagery afford information on the source areas for the lipids and pollen on land and their transport pathways to the ocean sites. This multidisciplinary approach on an almost continental scale provides clear evidence of latitudinal differences in lipid and pollen composition paralleling the major phytogeographic zonations on the adjacent continent. Dust and smoke aerosols are mainly derived from the western and central South African hinterland dominated by deserts, semi-deserts and savannah regions rich in C4 and CAM plants. The northern sites (Congo Fan area and northern Angola Basin), which get most of their terrestrial material from the Congo Basin and the Angolan highlands, may also receive some material from the Chad region. Very little aerosol from the African continent is transported to the most southerly sites in the Cape Basin. As can be expected from the present position of the phytogeographic zones, the carbon isotopic signatures of the n-alkanes and n-alkanols both become isotopically more enriched in 13C from north to south. The results of the study suggest that this combination of pollen data and compound-specific isotope geochemical proxies can be effectively applied in the reconstruction of past continental phytogeographic developments.