66 research outputs found

    Controls on gut phosphatisation : the trilobites from the Weeks Formation Lagerstätte (Cambrian; Utah)

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    Despite being internal organs, digestive structures are frequently preserved in Cambrian Lagerstätten. However, the reasons for their fossilisation and their biological implications remain to be thoroughly explored. This is particularly true with arthropods--typically the most diverse fossilised organisms in Cambrian ecosystems--where digestive structures represent an as-yet underexploited alternative to appendage morphology for inferences on their biology. Here we describe the phosphatised digestive structures of three trilobite species from the Cambrian Weeks Formation Lagerstätte (Utah). Their exquisite, three-dimensional preservation reveals unique details on trilobite internal anatomy, such as the position of the mouth and the absence of a differentiated crop. In addition, the presence of paired pygidial organs of an unknown function is reported for the first time. This exceptional material enables exploration of the relationships between gut phosphatisation and the biology of organisms. Indeed, soft-tissue preservation is unusual in these fossils as it is restricted to the digestive structures, which indicates that the gut played a central role in its own phosphatisation. We hypothesize that the gut provided a microenvironment where special conditions could develop and harboured a source of phosphorus. The fact that gut phosphatization has almost exclusively been observed in arthropods could be explained by their uncommon ability to store ions (including phosphorous) in their digestive tissues. However, in some specimens from the Weeks Formation, the phosphatisation extends to the entire digestive system, suggesting that trilobites might have had some biological particularities not observed in modern arthropods. We speculate that one of them might have been an increased capacity for ion storage in the gut tissues, related to the moulting of their heavily-mineralised carapace

    Are we losing the battle against cardiometabolic disease? The case for a paradigm shift in primary prevention

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    Kraushaar LE, Krämer A. Are we losing the battle against cardiometabolic disease? The case for a paradigm shift in primary prevention. BMC Public Health. 2009;9(1):64.Background: Cardiovascular and diabetic disease are the leading and preventable causes of death worldwide. The currently prognosticated dramatic increase in disease burden over the next two decades, however, bespeaks a low confidence in our prevention ability. This conflicts with the almost enthusiastic reporting of study results, which demonstrate substantial risk reductions secondary to simple lifestyle changes. Discussion: There is a case to be made for a disregard of the difference between statistical significance and clinical relevance of the reported data. Nevertheless, lifestyle change remains the main weapon in our battle against the epidemic of cardiometabolic disease. But along the way from risk screening to intervention to maintenance the compound inefficiencies of current primary preventive strategies marginalize their impact. Summary: Unless we dramatically change the ways in which we deploy preventive interventions we will inevitably lose the battle. In this paper we will argue for three provocative strategy changes, namely (a) the disbanding of screening in favor of population-wide enrollment into preventive interventions, (b) the substitution of the current cost utility analysis for a return-on-investment centered appraisal of interventions, and (c) the replacement of standardized programs modeled around acute care by individualized and perpetual interventions

    Lymphatic mapping and sentinel node biopsy in gynecological cancers: a critical review of the literature

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    Although it does not have a long history of sentinel node evaluation (SLN) in female genital system cancers, there is a growing number of promising study results, despite the presence of some aspects that need to be considered and developed. It has been most commonly used in vulvar and uterine cervivcal cancer in gynecological oncology. According to these studies, almost all of which are prospective, particularly in cases where Technetium-labeled nanocolloid is used, sentinel node detection rate sensitivity and specificity has been reported to be 100%, except for a few cases. In the studies on cervical cancer, sentinel node detection rates have been reported around 80–86%, a little lower than those in vulva cancer, and negative predictive value has been reported about 99%. It is relatively new in endometrial cancer, where its detection rate varies between 50 and 80%. Studies about vulvar melanoma and vaginal cancers are generally case reports. Although it has not been supported with multicenter randomized and controlled studies including larger case series, study results reported by various centers around the world are harmonious and mutually supportive particularly in vulva cancer, and cervix cancer. Even though it does not seem possible to replace the traditional approaches in these two cancers, it is still a serious alternative for the future. We believe that it is important to increase and support the studies that will strengthen the weaknesses of the method, among which there are detection of micrometastases and increasing detection rates, and render it usable in routine clinical practice

    The Initiative to Maximize Progress in Adolescent and Young Adult Cancer Therapy (IMPACT) Cohort Study: a population-based cohort of young Canadians with cancer

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    BACKGROUND: Cancer is the leading cause of disease-related death in adolescents and young adults (AYA). Annual improvements in AYA cancer survival have been inferior to those observed in children and older adults. Prior studies of AYA with cancer have been limited by their focus on patients from select treatment centres, reducing generalizability, or by being population-based but lacking diagnostic and treatment details. There is a critical need to conduct population-based studies that capture detailed patient, disease, treatment and system-level data on all AYA regardless of treatment location. METHODS/DESIGN: We will create a cohort of all AYA (aged 15–21 years) at the time of diagnosis with any malignancy between 1992 and 2011 in Ontario, Canada (n = 5,394). Subjects will be identified through the Ontario Cancer Registry and the final cohort will be expanded to include 2012 diagnoses, as these data become available. Detailed diagnostic, treatment and outcome data for those patients treated at a pediatric cancer centre will be provided by a population-based pediatric cancer registry (n = 1,030). For 15–18 year olds treated at adult centres (n = 923) and all 19–21 year olds (n = 3396), trained abstractors will collect the comparable data elements from medical records. We will link these data to population-based administrative health data that include physician billings, hospitalizations and emergency room visits. This will allow descriptions of health care access and use prior to cancer diagnosis, and during and after treatment. DISCUSSION: The IMPACT cohort will serve as a platform for addressing questions that span the AYA cancer journey. These will include determining which factors influence where AYA receive care, the impact of locus of care on the types and intensity of cancer therapy, appropriateness of surveillance for disease recurrence, access to clinical trials, and receipt of palliative and survivor care. Findings using the IMPACT cohort have the potential to lead to changes in practice and cancer policy, reduce mortality, and improve quality of life for AYA with cancer. The IMPACT data platform will be a permanent resource, accessible to researchers across Canada
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