936 resultados para paleogeographical and paleoecological significance


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Background: Obesity is a growing problem in industrial nations. The aim of this study was to determine the relationship between the body mass index (BMI) and the pattern of injury after polytrauma. Methods: This retrospective study included 651 patients with an injury severity score (ISS) ≥16 and aged ≥16 years who were subdivided into three groups: BMI < 25 kg/m2, BMI 25–30 kg/m2, and BMI > 30 kg/m2. The Abbreviated Injury Scale (AIS) was used to quantify the injuries in the different anatomical regions. The Murray score was assessed at admission and at its maximum during hospitalization to evaluate pulmonary problems. Data are presented as means ± standard errors of the means. One way analysis of variance, χ2 test and Kruskal-Wallis test were used for the analyses and the significance level was set at p < 0.05. Results: The AIS of the thorax was 3.2 ± 0.1 in the BMI < 25 kg/m2 group, 3.3 ± 0.1 in the BMI 25–30 kg/m2 group, and 2.8 ± 0.2 in the BMI > 30 kg/m2 group; p < 0.05. The Murray score at admission increased significantly with increasing BMI (0.8 ± 0.8 for BMI < 25 kg/m2, 0.9 ± 0.9 for BMI 25–30 kg/m2, and 1.0 ± 0.8 for BMI > 30 kg/m2; p < 0.05) as was the maximum Murray score during hospitalization (1.2 ± 0.9 for BMI < 25 kg/m2, 1.6 ± 1.0 for BMI 25–30 kg/m2, and 1.5 ± 0.9 for BMI > 30 kg/m2; p < 0.001). The number of ventilator days was also elevated significantly with increasing BMI (5.9 ± 0.4 for BMI < 25 kg/m2, 7.7 ± 0.8 for BMI 25–30 kg/m2, and 7.9 ± 1.6 for BMI > 30 kg/m2; p < 0.05). Conclusion: Overweight and obesity lead to a higher incidence of thoracic trauma in a polytrauma situation and may additionally handicap ventilation in an obstructive manner.

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Temporohyoid osteoarthropathy (THO) is a well-recognised clinical entity in horses. Temporohyoid osteoarthropathy is characterised by progressive osseous proliferation of the proximal portion of the stylohyoid and petrous temporal bones, and is generally described as a disease of middle-aged horses. More recent reports also attribute a variety of clinical syndromes in young horses to THO, requiring a diversification of approaches to confirm the diagnosis and its significance, and to guide conservative and surgical treatment options. This commentary will review the purported aetiology, clinical syndromes, available diagnostic tests and treatment options of equine THO.

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Pancreatic ductal adenocarcinoma (PDAC) ranks as the fourth commonest cause of cancer death while its incidence is increasing worldwide. For all stages, survival at 5 years is<5%. The lethal nature of pancreatic cancer is attributed to its high metastatic potential to the lymphatic system and distant organs. Lack of effective therapeutic options contributes to the high mortality rates of PDAC. Recent evidence suggests that epithelial-mesenchymal transition (EMT) plays an important role to the disease progression and development of drug resistance in PDAC. Tumor budding is thought to reflect the process of EMT which allows neoplastic epithelial cells to acquire a mesenchymal phenotype thus increasing their capacity for migration and invasion and help them become resistant to apoptotic signals. In a recent study by our own group the presence and prognostic significance of tumor budding in PDAC were investigated and an association between high-grade budding and aggressive clinicopathological features of the tumors as well as worse outcome of the patients was found. The identification of EMT phenotypic targets may help identifying new molecules so that future therapeutic strategies directed specifically against them could potentially have an impact on drug resistance and invasiveness and hence improve the prognosis of PDAC patients. The aim of this short review is to present an insight on the morphological and molecular aspects of EMT and on the factors that are involved in the induction of EMT in PDAC.

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Platelets represent one of the largest storage pools of angiogenic and oncogenic growth factors in the human body. The observation that thrombocytosis (platelet count >450,000/uL) occurs in patients with solid malignancies was made over 100 years ago. However, the clinical and biological implications as well as the underlying mechanism of paraneoplastic thrombocytosis associated with ovarian carcinoma remains unknown and were the focus of the current study. Following IRB approval, patient data were collected on 619 patients from 4 U.S. centers and used to test associations between platelet count at initial diagnosis, clinicopathologic factors, and outcome. In vitro effects of plasma-purified platelets on ovarian cancer cell proliferation, docetaxel-induced apoptosis, and migration were evaluated using BrdU-PI flow cytometric and two-chamber chemotaxis assays. In vivo effects of platelet depletion on tumor growth, proliferation, apoptosis, and angiogenesis were examined using an anti-platelet antibody (anti-mouse glycoprotein 1ba, Emfret) to reduce platelets by 50%. Complete blood counts and number of mature megakaryocytes in the spleen and bone marrow were compared between control mice and ovarian cancer-bearing mice. Plasma levels of key megakaryo- and thrombopoietic factors including thrombopoietin (TPO), IL-1a, IL-3, IL-4, IL-6, IL-11, G-CSF, GM-CSF, stem cell factor, and FLT-3 ligand were assayed in a subset of 150 patients at the time of initial diagnosis with advanced stage, high grade epithelial ovarian cancer using immunobead-based cytokine profiling coupled with the Luminex® xMAP platform. Plasma cytokines significantly associated with thrombocytosis in ovarian cancer patients were subsequently evaluated in mouse models of ovarian cancer using ELISA immunoassays. The results of human and mouse plasma cytokine profiling were used to inform subsequent in vivo studies evaluating the effect of siRNA-induced silencing of select megakaryo- and thrombopoietic cytokines on paraneoplastic thrombocytosis. Thirty-one percent of patients had thrombocytosis at initial diagnosis. Compared to patients with normal platelet counts, women with thrombocytosis were significantly more likely to have advanced stage disease (p<0.001) and poor median progression-free (0.94 vs 1.35 years, p<0.001) and overall survival (2.62 vs 4.65 years, p<0.001). On multivariate analysis, thrombocytosis remained an independent predictor of decreased overall survival. Our analysis revealed that thrombocytosis significantly increases the risk of VTE in ovarian cancer patients and that thrombocytosis is an independent predictor of increased mortality in women who do develop a blood clot. Platelets increased ovarian cancer cell proliferation and migration by 4.1- and 2.8-fold (p<0.01), respectively. Platelets reduced docetaxel-induced apoptosis in ovarian cancer cells by 2-fold (p<0.001). In vivo, platelet depletion reduced tumor growth by 50%. Staining of in vivo specimens revealed decreased tumor cell proliferation (p<0.001) and increased tumor and endothelial cell apoptosis (p<0.01). Platelet depletion also significantly decreased microvessel density and pericyte coverage (p<0.001). Platelet counts increase by 31-130% in mice with invasive ovarian cancer compared to controls (p<0.01) and strongly correlate with mean megakaryocyte counts in the spleen and bone marrow (r=0.95, p<0.05). Plasma levels of TPO, IL-6, and G-CSF were significantly increased in ovarian cancer patients with thrombocytosis. Plasma levels of the same cytokines were found to be significantly elevated in orthotopic mouse models of ovarian cancer, which consistently develop paraneoplastic thromocytosis. Silencing TPO, IL-6, and G-CSF significantly abrogated paraneoplastic thrombocytosis in vivo. This study provides new understanding of the clinical and biological significance of paraneoplastic thrombocytosis in ovarian cancer and uncovers key humoral factors driving this process. Blocking the development of paraneoplastic thrombocytosis and interfering with platelet-cancer cell interactions could represent novel therapeutic strategies.

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CONTRIBUTION OF ECTODOMAIN MUTATIONS IN EPIDERMAL GROWTH FACTOR RECEPTOR TO SIGNALING IN GLIOBLASTOMA MULTIFORME Publication No._________ Marta Rojas, M.S. Supervisory Professor: Oliver Bögler, Ph.D. The Cancer Genome Atlas (TCGA) has conducted a comprehensive analysis of a large tumor cohort and has cataloged genetic alterations involving primary sequence variations and copy number aberrations of genes involved in key signaling pathways in glioblastoma (GBM). This dataset revealed missense ectodomain point mutations in epidermal growth factor receptor (EGFR), but the biological and clinical significance of these mutations is not well defined in the context of gliomas. In our study, we focused on understanding and defining the molecular mechanisms underlying the functions of EGFR ectodomain mutants. Using proteomic approaches to broadly analyze cell signaling, including antibody array and mass spectrometry-based methods, we found a differential spectrum of tyrosine phosphorylation across the EGFR ectodomain mutations that enabled us to stratify them into three main groups that correlate with either wild type EGFR (EGFR) or the long-studied mutant, EGFRvIII. Interestingly, one mutant shared characteristics of both groups suggesting a continuum of behaviors along which different mutants fall. Surprisingly, no substantial differences were seen in activation of classical downstream signaling pathways such as Akt and S6 pathways between these classes of mutants. Importantly, we demonstrated that ectodomain mutations lead to differential tumor growth capabilities in both in vitro (anchorage independent colony formation) and in vivo conditions (xenografts). Our data from the biological characterization allowed us to categorize the mutants into three main groups: the first group typified by EGFRvIII are mutations with a more aggressive phenotype including R108K and A289T; a second group characterized by a less aggressive phenotype exemplified by EGFR and the T263P mutation; and a third group which shared characteristics from both groups and is exemplified by the mutation A289D. In addition, we treated cells overexpressing the mutants with various agents employed in the clinic including temozolomide, cisplatin and tarceva. We found that cells overexpressing the mutants in general displayed resistance to the treatments. Our findings yield insights that help with the molecular characterization of these mutants. In addition, our results from the drug studies might be valuable in explaining differential responses to specific treatments in GBM patients.

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The decadal-scale variability in winter hazardous winds in northern Switzerland from 1871 to present is investigated in the Twentieth Century Reanalysis (20CR). Independent wind speed measurements taken at Zurich climate station show that the interannual and decadal variability in hazardous winds in northern Switzerland is realistically represented in the 20CR. Both time series exhibit pronounced decadal-scale variability with periods between approximately 36 and 47 years. At these periodicities, the hazardous wind variability in northern Switzerland is positively correlated with the variability in the North Atlantic Oscillation, however the strength and statistical significance of their co-variability varies over time.

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Malnutrition in hospital patients is of important medical and economic significance. The adverse consequences of malnutrition on quality of life and many more factors such as morbidity, mortality, tolerance of treatments and length of hospital stay are well documented in the medical literature. Nevertheless, the effects of malnutrition are still often underestimated and hence malnutrition is not recognised as a distinct diagnosis. Moreover, malnutrition is rarely documented in medical reports and often not adequately treated with adverse effects. The reason for this neglectfulness are diverse, e. g. inadequate training of doctors and nurses in clinical nutrition and lack of sensibilisation of the hospital staff for the problem of malnutrition. Therefore, a systematic screening for malnutrition is rarely undertaken in Swiss hospitals. The introduction of the Swiss-DRG system (DRG, diagnosis related groups) in January 2012 gave the chance to boost recording and to document malnutrition in a standardised way in the patient history, and to code precisely malnutrition as a distinct diagnosis. Moreover, this approach allowed to document the specific nutritional therapy. Here, we describe the way of documenting and coding malnutrition in the Swiss-DRG system and the medical and economic consequences of this procedure.

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The European Registry for Patients with Mechanical Circulatory Support (EUROMACS) was founded on 10 December 2009 with the initiative of Roland Hetzer (Deutsches Herzzentrum Berlin, Berlin, Germany) and Jan Gummert (Herz- und Diabeteszentrum Nordrhein-Westfalen, Bad Oeynhausen, Germany) with 15 other founding international members. It aims to promote scientific research to improve care of end-stage heart failure patients with ventricular assist device or a total artificial heart as long-term mechanical circulatory support. Likewise, the organization aims to provide and maintain a registry of device implantation data and long-term follow-up of patients with mechanical circulatory support. Hence, EUROMACS affiliated itself with Dendrite Clinical Systems Ltd to offer its members a software tool that allows input and analysis of patient clinical data on a daily basis. EUROMACS facilitates further scientific studies by offering research groups access to any available data wherein patients and centres are anonymized. Furthermore, EUROMACS aims to stimulate cooperation with clinical and research institutions and with peer associations involved to further its aims. EUROMACS is the only European-based Registry for Patients with Mechanical Circulatory Support with rapid increase in institutional and individual membership. Because of the expeditious data input, the European Association for Cardiothoracic Surgeons saw the need to optimize the data availability and the significance of the registry to improve care of patients with mechanical circulatory support and its potential contribution to scientific intents; hence, the beginning of their alliance in 2012. This first annual report is designed to provide an overview of EUROMACS' structure, its activities, a first data collection and an insight to its scientific contributions.

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Purpose. Understanding siblings' experiences after a major childhood burn injury was the purpose of this mixed method, qualitative dominant study. The following research questions guided this project: How do siblings describe the impact of a major childhood burn injury experience? How do sibling relationship factors of warmth/closeness, relative status/power, conflict, and rivalry further clarify their relationship and their experience after a major burn injury? ^ Methods. A mixed method, qualitative dominant, design was implemented to understand the sibling experiences in a family with a child suffering from a major burn injury. Informants were selected from patients with childhood burn injuries attending the reconstructive clinic at a Gulf coast children's specialty hospital. The qualitative portion used the life story method, a narrative process, to portray the long-term impact on sibling relationships. A "case" represents a family unit and could be composed of one or multiple family members. Participants from 22 cases (N = 40 participants) were interviewed. Interviews were conducted in person and via telephone. The quantitative portion, or the embedded part of this mixed method design, used the Sibling Relationship Questionnaire Revised (SRQ-R) to conduct an additional structured interview and acquire scoring data. It was postulated that the SRQ-R would provide another perspective on the sibling experience and expand the qualitative data analysis. Thematic analysis was implemented on the qualitative interview data including the qualitative data from the interviews structured on the SRQ-R. Additionally, scores on the SRQ-R were tabulated to further describe the cases. ^ Results. The overall thematic pattern for the sibling relationship in families having a child with a major burn injury was that of normalization. Areas of normalization as well as the process of adjustment were the major themes. Areas of normalization were found in play and other activities, in school and work, and in family relations with their siblings and their parents. The process of adjustment in the sibling relationship was described as varied, involved school and work re-entry, and might even change their life perspective. Further analysis included an examination of the cases in which more than one person were interviewed and completed the SRQ-R. Participants from five ( n = 11) of six cases (n = 14), scored above 3.0 on the five-point scale on the Warmth/Closeness construct, indicating they perceived the sibling relationship as close. Five participants scored high on the Conflict construct and four participants scored high on the Rivalry construct. Finally, Relative Status/Power was low or negative in the six cases (n = 13). ^ Conclusions/implications. These findings suggest the importance of returning to normalcy for many of the families and the significance of sibling relationships on the process. Some of these families were able to use this major life event in a positive way to promote normalization. ^

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Background. The population-based Houston Tuberculosis Initiative (HTI) study has enrolled and gathered demographic, social, behavioral, and disease related data on more than 80% of all reported Mycobacterium Tuberculosis (MTB) cases and 90% of all culture positive patients in Houston/Harris County over a 9 year period (from October 1995-September 2004). During this time period 33% (n=1210) of HTI MTB cases have reported a history of drug use. Of those MTB cases reporting a history of drug use, a majority of them (73.6%), are non-injection drug users (NIDUs). ^ Other than HIV, drug use is the single most important risk factor for progression from latent to infectious tuberculosis (TB). In addition, drug use is associated with increased transmission of active TB, as seen by the increased number of clonally related strains or clusters (see definition on page 30) found in this population. The deregulatory effects of drug use on immune function are well documented. Associations between drug use and increased morbidity have been reported since the late 1970's. However, limited research focused on the immunological consequence of non-injection drug use and its relation to tuberculosis infection among TB patients is available. ^ Methods. TB transmission patterns, symptoms, and prevalence of co-morbidities were a focus of this project. Smoking is known to suppress Nitric Oxide (NO) production and interfere with immune function. In order to limit any possible confounding due to smoking two separate analyses were done. Non-injection drug user smokers (NIDU-S) were compared to non-drug user smokers (NDU-S) and non-injection drug user non-smokers (NIDU-NS) were compared to non-drug user non-smokers (NDU-NS) individually. Specifically proportions, chi-square p-values, and (where appropriate) odds ratios with 95% confidence intervals were calculated to assess characteristics and potential associations of co-morbidities and symptoms of TB among NIDUs HTI TB cases. ^ Results. Significant differences in demographic characteristics and risk factors were found. In addition drug users were found to have a decreased risk for cancer, diabetes mellitus, and chronic pulmonary disease. They were at increased risk of having HIV/AIDS diagnosis, liver disease, and trauma related morbidities. Drug users were more likely to have pulmonary TB disease, and a significantly increased amount of clonally related strains of TB or "clusters" were seen in both smokers and non-smoker drug users when compared to their non-drug user counterparts. Drug users are more likely to belong to print groups (clonally related TB strains with matching spoligotypes) including print one and print three and the Beijing family group, s1. Drug users were found to be no more likely to experience drug resistance to TB therapy and were likely to be cured of disease upon completion of therapy. ^ Conclusion. Drug users demographic and behavioral risk factors put them at an increased risk contracting and spreading TB disease throughout the community. Their increased levels of clustering are evidence of recent transmission and the significance of certain print groups among this population indicate the transmission is from within the social family. For these reasons a focus on this "at risk population" is critical to the success of future public health interventions. Successful completion of directly observed therapy (DOT), the tracking of TB outbreaks and incidence through molecular characterization, and increased diagnostic strategies have led to the stabilization of TB incidence in Houston, Harris County over the past 9 years and proven that the Houston Tuberculosis Initiative has played a critical role in the control and prevention of TB transmission. ^

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Birth defects are the leading cause of infant mortality in the United States and are a major cause of lifetime disability. However, efforts to understand their causes have been hampered by a lack of population-specific data. During 1990–2004, 22 state legislatures responded to this need by proposing birth defects surveillance legislation (BDSL). The contrast between these states and those that did not pass BDSL provides an opportunity to better understand conditions associated with US public health policy diffusion. ^ This study identifies key state-specific determinants that predict: (1) the introduction of birth defects surveillance legislation (BDSL) onto states' formal legislative agenda, and (2) the successful adoption of these laws. Secondary aims were to interpret these findings in a theoretically sound framework and to incorporate evidence from three analytical approaches. ^ The study begins with a comparative case study of Texas and Oregon (states with divergent BDSL outcomes), including a review of historical documentation and content analysis of key informant interviews. After selecting and operationalizing explanatory variables suggested by the case study, Qualitative Comparative Analysis (QCA) was applied to publically available data to describe important patterns of variation among 37 states. Results from logistic regression were compared to determine whether the two methods produced consistent findings. ^ Themes emerging from the comparative case study included differing budgetary conditions and the significance of relationships within policy issue networks. However, the QCA and statistical analysis pointed to the importance of political parties and contrasting societal contexts. Notably, state policies that allow greater access to citizen-driven ballot initiatives were consistently associated with lower likelihood of introducing BDSL. ^ Methodologically, these results indicate that a case study approach, while important for eliciting valuable context-specific detail, may fail to detect the influence of overarching, systemic variables, such as party competition. However, QCA and statistical analyses were limited by a lack of existing data to operationalize policy issue networks, and thus may have downplayed the impact of personal interactions. ^ This study contributes to the field of health policy studies in three ways. First, it emphasizes the importance of collegial and consistent relationships among policy issue network members. Second, it calls attention to political party systems in predicting policy outcomes. Finally, a novel approach to interpreting state data in a theoretically significant manner (QCA) has been demonstrated.^

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The intent of this research was to identify the level of risk methanol posed to a fetus during an ethanol co-exposure. This investigation was prompted by the known competitive inhibition properties of ethanol and the developmental toxicity of methanol. Integrated into this research was the practicality necessitated by regulatory processes, namely: does the risk justify the expense of additional research. To this end, the scope and nature of exposures were summarized to illustrate the ubiquity of these chemicals and the potential for dual exposure. Similarly, severity of outcome was evaluated by systematically reviewing the LOAELs, NOAELs, and statistical significance contained in methanol-induced developmental studies. Results. Blood methanol levels corresponding to developmental effects in laboratory studies were found to be substantially higher than the blood methanol levels predicted in high-risk methanol-ethanol exposure scenarios. This indicates that ethanol would not likely exacerbate methanol toxicity to the point of teratogenicity; however, it is important to note that the developmental toxicity of ethanol—an established human teratogen—was not included in the evaluation. Ethanol's contribution as a developmental toxicant rather than merely as an attenuator of methanol toxicity undermines the severity of effects possible from this chemical combination. Therefore further evaluation is needed to assess the developmental toxicities following dual exposures before rendering methanol and ethanol a high-priority mixture.^

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We discovered and investigated several cold-seep sites in four depth zones of the Sea of Okhotsk off Northeast Sakhalin: outer shelf (160-250 m), upper slope (250-450 m), intermediate slope (450-800 m), and Derugin Basin (1450-1600 m). Active seepage of free methane or methane-rich fluids was detected in each zone. However, seabed photography and sampling revealed that the number of chemoautotrophic species decreases dramatically with decreasing water depth. At greatest depths in the Derugin Basin, the seeps were inhabited by bacterial mats and bivalves of the families Vesicomyidae (Calyptogena aff. pacifica, C. rectimargo, Archivesica sp.), Solemyidae (Acharax sp.) and Thyasiridae (Conchocele bisecta). In addition, pogonophoran tubeworms of the family Sclerolinidae were found in barite edifices. At the shallowest sites, on the shelf at 160 m, the seeps lack chemoautotrophic macrofauna; their locations were indicated only by the patchy occurrence of bacterial mats. Typical seep-endemic metazoans with chemosynthetic symbionts were confined to seep sites at depths below 370 m. A comparative analysis of the structure of seep and background communities suggests that differences in predation pressure may be an important determinant of this pattern. The abundance of predators such as carnivorous brachyurans and asteroids, which can invade seeps from adjacent habitats and efficiently prey on sessile seep bivalves, decreased very pronouncedly with depth. We conclude from the obvious correlation with the conspicuous pattern in the distribution of seep assemblages that, on the shelf and at the upper slope, predator pressure may be high enough to effectively impede any successful settlement of viable populations of seep-endemic metazoans. However, there was also evidence that other depth-related factors, such as bottom-water current, sedimentary regimes, oxygen concentrations and the supply of suitable settling substrates, may additionally regulate the distribution of seep fauna in the area. As a consequence of the pronounced pattern in the distribution of seep communities, their ecological significance as food sources of surrounding background fauna increased with water depth. Isotopic analyses suggest that in the Derugin Basin seep colonists feed on chemoautotrophic seep organisms, either directly or by preying on metazoans with chemosynthetic symbionts. In contrast, seep organisms apparently do not contribute to the nutrition of the adjacent background fauna on the shelf and at the slope. In this area, elevated epifaunal abundances at seep sites were caused primarily by the availability of suitable settling substrates rather than by an enrichment of food supply.