4,225 research outputs found

    Effects of beta-carotene on antioxidant status in rats with chronic alcohol consumption

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    [[abstract]]This study examined the effects of beta-carotene on antioxidant status in rats with chronic alcohol consumption. At the beginning of experiment (week 0), according to both the plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities, rats (n = 24) were divided into 3 groups and fed with a standard diet (group C), a diet containing ethanol (group E), or a diet containing ethanol and beta-carotene (group E+B). After 10 weeks, plasma AST and ALT, fat accumulation in the liver, antioxidant enzyme activities in erythrocytes and the liver, malondialdehyde (MDA), and alpha-tocopherol and retinol in plasma and hepatic samples were analyzed. The chronic alcohol diet significantly increased AST and ALT levels in plasma, and these changes were prevented by supplementing the diet with beta-carotene. Glutathione (GSH) in erythrocytes and in the liver was significantly elevated in rats fed with a diet containing beta-carotene. The results indicate that beta-carotene supplementation can prevent ethanol-induced liver damage and increase GSH concentrations in erythrocytes and the liver. Copyright (C) 2009 John Wiley & Sons, Ltd

    Cloning, expression and location of RNase9 in human epididymis

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    <p>Abstract</p> <p>Background</p> <p>Mammalian spermatozoa become fully motile and fertile during transit through the luminal fluid of the epididymis. At least 200 proteins are present in the epididymal lumen, but the potential roles of these luminal proteins in male fertility are unknown. Investigation of the function of these proteins will elucidate the mechanism of sperm maturation, and also provide new drug targets for male contraception. We cloned RNase9 from a human epididymis cDNA library for characterization and analysis of its functions.</p> <p>Findings</p> <p>It was predicted that human <it>RNase9 </it>gene was located on chromosome 14q11.2 and encoded a 205 amino acids protein with a signal peptide of 26 amino acids at the N-terminus. The protein had eight conserved cysteine residues characteristic of the RNase A family members and several potential post-translational modification sites.</p> <p>At the transcriptional level, <it>RNase9 </it>was expressed in a wide variety of tissues, and the expression was higher in men than in boys. <it>RNase9 </it>was localized to the post-equatorial region of the sperms' head. Immunofluorescence staining showed that RNase9 protein was present mostly in the epithelium of the epididymal tubule. Recombinant RNase9 had no ribonuclease activity. In addition, RNase9 had no detectable effect on sperm motility and fertilization as demonstrated by blocking spermatozoa with anti-RNase9 polyclonal serum.</p> <p>Conclusion</p> <p><it>RNase9 </it>is expressed in a wide variety of tissues. It is located on the post-equatorial region of the sperm head and the epithelium of epididymal tubule. Although <it>RNase9 </it>belongs to the RNase A family, it has no ribonuclease activity.</p

    Investigation of the cerebral hemodynamic response function in single blood vessels by functional photoacoustic microscopy

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    The specificity of the hemodynamic response function (HRF) is determined spatially by the vascular architecture and temporally by the evolution of hemodynamic changes. Here, we used functional photoacoustic microscopy (fPAM) to investigate single cerebral blood vessels of rats after left forepaw stimulation. In this system, we analyzed the spatiotemporal evolution of the HRFs of the total hemoglobin concentration (HbT), cerebral blood volume (CBV), and hemoglobin oxygen saturation (SO2). Changes in specific cerebral vessels corresponding to various electrical stimulation intensities and durations were bilaterally imaged with 36 × 65-μm2 spatial resolution. Stimulation intensities of 1, 2, 6, and 10 mA were applied for periods of 5 or 15 s. Our results show that the relative functional changes in HbT, CBV, and SO2 are highly dependent not only on the intensity of the stimulation, but also on its duration. Additionally, the duration of the stimulation has a strong influence on the spatiotemporal characteristics of the HRF as shorter stimuli elicit responses only in the local vasculature (smaller arterioles), whereas longer stimuli lead to greater vascular supply and drainage. This study suggests that the current fPAM system is reliable for studying relative cerebral hemodynamic changes, as well as for offering new insights into the dynamics of functional cerebral hemodynamic changes in small animals. © 2012 Society of Photo-Optical Instrumentation Engineers (SPIE)

    Mouse models of atherosclerosis: a historical perspective and recent advances.

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    Atherosclerosis represents a significant cause of morbidity and mortality in both the developed and developing countries. Animal models of atherosclerosis have served as valuable tools for providing insights on its aetiology, pathophysiology and complications. They can be used for invasive interrogation of physiological function and provide a platform for testing the efficacy and safety of different pharmacological therapies. Compared to studies using human subjects, animal models have the advantages of being easier to manage, with controllable diet and environmental risk factors. Moreover, pathophysiological changes can be induced either genetically or pharmacologically to study the harmful effects of these interventions. There is no single ideal animal model, as different systems are suitable for different research objectives. A good understanding of the similarities and differences to humans enables effective extrapolation of data for translational application. In this article, we will examine the different mouse models for the study and elucidation of the pathophysiological mechanisms underlying atherosclerosis. We also review recent advances in the field, such as the role of oxidative stress in promoting endoplasmic reticulum stress, mitochondrial dysfunction and mitochondrial DNA damage, which can result in vascular inflammation and atherosclerosis. Finally, novel therapeutic approaches to reduce vascular damage caused by chronic inflammation using microRNA and nano-medicine technology, are discussed.YC is supported by a project grant from the ESRC for her doctoral studies at the University of Cambridge. GT was supported by the BBSRC Doctoral Training Award and Assistant Professorships from The Croucher Foundation of Hong Kong

    Rapid identification of the medicinal plant Taraxacum formosanum and distinguishing of this plant from its adulterants by ribosomal DNA internal transcribed spacer (ITS) based DNA barcode

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    Original identification of medicinal plants is essential for quality control. In this study, the internal transcribed spacer 2 (ITS2) nuclear ribosomal DNA served as a DNA barcode and was amplified by allele-specific PCR. This approach was exploited to differentiate Taraxacum formosanum from five related adulterants. Using a set of designed PCR primers, a highly specific 223 bp PCR product of T. formosanum was successfully amplified by PCR. However, no similar DNA fragment was amplified from any of the other adulterants. This indicates that, our allele specific primers have high specificity and can accurately discriminate T. formosanum from its adulterant plants.Key words: Medicinal plant, polymerase chain reaction (PCR), authentication, Taraxacum formosanum, traditional Chinese medicinal, internal transcribed spacers 2 (ITS2)

    IT Value in Public Administrations: a Model Proposal for E-Procurement

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    Recent studies have affirmed the necessity of a discontinuity in the method of investigating the value produced in organisations by IT. Existing studies have in common a prevailing (when not exclusive) attention paid to the private sector, as testified by the frequent use of income or financial indicators to measure benefits. These approaches however cannot be directly applied to public utility organisations like public administrations. Taking into account this scenario, the present exploratory work looks at the analysis of IT investments in the public sector by identifying a viable approach to research in this domain. To move towards this objective, procurement management has been taken as the field to be observed, and an Italian publich Local Healthcare Agency which has managed several e-procurement projects has been analysed. This case represents a valuable context for examination and discussion because the outcomes of each project were evaluated in details. A riche IT Value Model devoted to the private secotr has been adopted and discussed, and later some resulting adaptations are suggested, together with some hints and limitations.Recent studies have affirmed the necessity of a discontinuity in the method of investigating the value produced in organisations by IT. Existing studies have in common a prevailing (when not exclusive) attention paid to the private sector, as testified by the frequent use of income or financial indicators to measure benefits. These approaches however cannot be directly applied to public utility organisations like public administrations. Taking into account this scenario, the present exploratory work looks at the analysis of IT investments in the public sector by identifying a viable approach to research in this domain. To move towards this objective, procurement management has been taken as the field to be observed, and an Italian publich Local Healthcare Agency which has managed several e-procurement projects has been analysed. This case represents a valuable context for examination and discussion because the outcomes of each project were evaluated in details. A riche IT Value Model devoted to the private secotr has been adopted and discussed, and later some resulting adaptations are suggested, together with some hints and limitations.Monograph's chapter

    The Unreasonable Effectiveness of Texture Transfer for Single Image Super-resolution

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    While implicit generative models such as GANs have shown impressive results in high quality image reconstruction and manipulation using a combination of various losses, we consider a simpler approach leading to surprisingly strong results. We show that texture loss alone allows the generation of perceptually high quality images. We provide a better understanding of texture constraining mechanism and develop a novel semantically guided texture constraining method for further improvement. Using a recently developed perceptual metric employing "deep features" and termed LPIPS, the method obtains state-of-the-art results. Moreover, we show that a texture representation of those deep features better capture the perceptual quality of an image than the original deep features. Using texture information, off-the-shelf deep classification networks (without training) perform as well as the best performing (tuned and calibrated) LPIPS metrics. The code is publicly available.Comment: 19 pages, 14 figure

    Cognitive appraisal of environmental stimuli induces emotion-like states in fish

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    The occurrence of emotions in non-human animals has been the focus of debate over the years. Recently, an interest in expanding this debate to non-tetrapod vertebrates and to invertebrates has emerged. Within vertebrates, the study of emotion in teleosts is particularly interesting since they represent a divergent evolutionary radiation from that of tetrapods, and thus they provide an insight into the evolution of the biological mechanisms of emotion. We report that Sea Bream exposed to stimuli that vary according to valence (positive, negative) and salience (predictable, unpredictable) exhibit different behavioural, physiological and neuromolecular states. Since according to the dimensional theory of emotion valence and salience define a two-dimensional affective space, our data can be interpreted as evidence for the occurrence of distinctive affective states in fish corresponding to each the four quadrants of the core affective space. Moreover, the fact that the same stimuli presented in a predictable vs. unpredictable way elicited different behavioural, physiological and neuromolecular states, suggests that stimulus appraisal by the individual, rather than an intrinsic characteristic of the stimulus, has triggered the observed responses. Therefore, our data supports the occurrence of emotion-like states in fish that are regulated by the individual's perception of environmental stimuli.European Commission [265957 Copewell]; Fundacao para a Ciencia e Tecnologia [SFRH/BD/80029/2011, SFRH/BPD/72952/2010]info:eu-repo/semantics/publishedVersio
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