45 research outputs found

    Abnormal X : autosome ratio, but normal X chromosome inactivation in human triploid cultures

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    BACKGROUND: X chromosome inactivation (XCI) is that aspect of mammalian dosage compensation that brings about equivalence of X-linked gene expression between females and males by inactivating one of the two X chromosomes (Xi) in normal female cells, leaving them with a single active X (Xa) as in male cells. In cells with more than two X's, but a diploid autosomal complement, all X's but one, Xa, are inactivated. This phenomenon is commonly thought to suggest 1) that normal development requires a ratio of one Xa per diploid autosomal set, and 2) that an early event in XCI is the marking of one X to be active, with remaining X's becoming inactivated by default. RESULTS: Triploids provide a test of these ideas because the ratio of one Xa per diploid autosomal set cannot be achieved, yet this abnormal ratio should not necessarily affect the one-Xa choice mechanism for XCI. Previous studies of XCI patterns in murine triploids support the single-Xa model, but human triploids mostly have two-Xa cells, whether they are XXX or XXY. The XCI patterns we observe in fibroblast cultures from different XXX human triploids suggest that the two-Xa pattern of XCI is selected for, and may have resulted from rare segregation errors or Xi reactivation. CONCLUSION: The initial X inactivation pattern in human triploids, therefore, is likely to resemble the pattern that predominates in murine triploids, i.e., a single Xa, with the remaining X's inactive. Furthermore, our studies of XIST RNA accumulation and promoter methylation suggest that the basic features of XCI are normal in triploids despite the abnormal X:autosome ratio

    Levosimendan Administration in Limb Ischemia: Multicomponent Signaling Serving Kidney Protection

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    AIMS AND OBJECTIVES: Acute renal failure is a severe complication of lower extremity major arterial reconstructions, which could even be fatal. Levosimendan is a dual-acting positive inotropic and vasodilatory agent, which is suspected to have protective effects against cardiac ischemia. However, there is no data available on lower limb or remote organ ischemic injuries therefore the aim of the study was to investigate the effect of levosimendan on lower limb ischemia-reperfusion injury and the corollary renal dysfunction. METHODS: Male Wistar rats underwent 180 min bilateral lower limb ischemia followed by 4 or 24 hours of reperfusion. Intravenous Levosimendan was administered continuously (0.2mug/bwkg/min) throughout the whole course of ischemia and the first 3h of reperfusion. Results were compared with sham-operated and ischemia-reperfusion groups. Hemodynamic monitoring was performed by invasive arterial blood pressure measurement. Kidney and lower limb muscle microcirculation was registered by a laser Doppler flowmeter. After 4h and 24h of reperfusion, serum, urine and histological samples were collected. RESULTS: Systemic hemodynamic parameters and microcirculation of kidney and the lower limb significantly improved in the Levosimendan treated group. Muscle viability was significantly preserved 4 and 24 hours after reperfusion. At the same time, renal functional laboratory tests and kidney histology demonstrated significantly less expressive kidney injury in Levosimendan groups. TNF-alpha levels were significantly less elevated in the Levosimendan group 4 hours after reperfusion. CONCLUSION: The results claim a protective role for Levosimendan administration during major vascular surgeries to prevent renal complications

    Listeria monocytogenes in Milk Products

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    peer-reviewedMilk and milk products are frequently identified as vectors for transmission of Listeria monocytogenes. Milk can be contaminated at farm level either by indirect external contamination from the farm environment or less frequently by direct contamination of the milk from infection in the animal. Pasteurisation of milk will kill L. monocytogenes, but post-pasteurisation contamination, consumption of unpasteurised milk and manufacture of unpasteurised milk products can lead to milk being the cause of outbreaks of listeriosis. Therefore, there is a concern that L. monocytogenes in milk could lead to a public health risk. To protect against this risk, there is a need for awareness surrounding the issues, hygienic practices to reduce the risk and adequate sampling and analysis to verify that the risk is controlled. This review will highlight the issues surrounding L. monocytogenes in milk and milk products, including possible control measures. It will therefore create awareness about L. monocytogenes, contributing to protection of public health

    Predicting climate change using response theory: global averages and spatial patterns

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    The provision of accurate methods for predicting the climate response to anthropogenic and natural forcings is a key contemporary scientific challenge. Using a simplified and efficient open-source general circulation model of the atmosphere featuring O(105105) degrees of freedom, we show how it is possible to approach such a problem using nonequilibrium statistical mechanics. Response theory allows one to practically compute the time-dependent measure supported on the pullback attractor of the climate system, whose dynamics is non-autonomous as a result of time-dependent forcings. We propose a simple yet efficient method for predicting—at any lead time and in an ensemble sense—the change in climate properties resulting from increase in the concentration of CO22 using test perturbation model runs. We assess strengths and limitations of the response theory in predicting the changes in the globally averaged values of surface temperature and of the yearly total precipitation, as well as in their spatial patterns. The quality of the predictions obtained for the surface temperature fields is rather good, while in the case of precipitation a good skill is observed only for the global average. We also show how it is possible to define accurately concepts like the inertia of the climate system or to predict when climate change is detectable given a scenario of forcing. Our analysis can be extended for dealing with more complex portfolios of forcings and can be adapted to treat, in principle, any climate observable. Our conclusion is that climate change is indeed a problem that can be effectively seen through a statistical mechanical lens, and that there is great potential for optimizing the current coordinated modelling exercises run for the preparation of the subsequent reports of the Intergovernmental Panel for Climate Change

    Engaging with Faith Councils to Develop Stoma-specific Fatawās: A Novel Approach to the Healthcare Needs of Muslim Colorectal Patients.

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    Intestinal stomas are common. Muslims report significantly lower quality of life following stoma surgery compared to non-Muslims. A fatwā is a ruling on a point of Islamic law according to a recognised religious authority. The use of fatawās to guide health-related decision-making has becoming an increasingly popular practice amongst Muslims, regardless of geographic location. This project aimed to improve the quality of life of Muslim ostomates by addressing faith-specific stoma concerns. Through close collaboration with Muslim ostomates, a series of 10 faith-related questions were generated, which were posed to invited local faith leaders during a stoma educational event. Faith leaders received education concerning the realities of stoma care before generating their fatawās. The event lead to the formulation of a series of stoma-specific fatawās representing Hanafi and Salafi scholarship, providing faith-based guidance for Muslim ostomates and their carers. Enhanced communication between healthcare providers and Islamic faith leaders allows for the delivery of informed fatawās that directly benefit Muslim patients and may represent an efficient method of improving health outcomes in this faith group

    Mitigating hypothetical bias in willingness to pay studies: post-estimation uncertainty and anchoring on irrelevant information

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    One possible source of hypothetical bias in willingness to pay (WTP) estimates is response uncertainty, referring to subject’s uncertainty about the value of the good under assessment. It has been argued that uncertainty can be measured using the post-valuation ‘certainty question’ that asks: ‘How certain are you about your stated WTP?’ and marks the degree of certainty on a quantitative or a qualitative scale. Research has shown that the self- reported certainty evaluations can help mitigate hypothetical bias and obtain increasingly accurate WTP estimates. These study reports present a simple test of reliability of post-valuation certainty assessment and then looks at the empirical evidence for clues regarding the general usefulness of certainty adjustment in mitigating hypothetical bias in WTP studies. We find that the post-estimation uncertainty scores are malleable, i.e., significantly correlated with entirely irrelevant information. We conclude that more robust evidence could justify the routine inclusion of certainty evaluation in WTP studies although in the meantime the interpretation of certainty- adjusted WTP values should be approached cautiously
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