438 research outputs found

    Serine Protease Variants Encoded by Echis ocellatus Venom Gland cDNA: Cloning and Sequencing Analysis

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    Envenoming by Echis saw-scaled viper is the leading cause of death and morbidity in Africa due to snake bite. Despite its medical importance, there have been few investigations into the toxin composition of the venom of this viper. Here, we report the cloning of cDNA sequences encoding four groups or isoforms of the haemostasis-disruptive Serine protease proteins (SPs) from the venom glands of Echis ocellatus. All these SP sequences encoded the cysteine residues scaffold that form the 6-disulphide bonds responsible for the characteristic tertiary structure of venom serine proteases. All the Echis ocellatus EoSP groups showed varying degrees of sequence similarity to published viper venom SPs. However, these groups also showed marked intercluster sequence conservation across them which were significantly different from that of previously published viper SPs. Because viper venom SPs exhibit a high degree of sequence similarity and yet exert profoundly different effects on the mammalian haemostatic system, no attempt was made to assign functionality to the new Echis ocellatus EoSPs on the basis of sequence alone. The extraordinary level of interspecific and intergeneric sequence conservation exhibited by the Echis ocellatus EoSPs and analogous serine proteases from other viper species leads us to speculate that antibodies to representative molecules should neutralise (that we will exploit, by epidermal DNA immunization) the biological function of this important group of venom toxins in vipers that are distributed throughout Africa, the Middle East, and the Indian subcontinent

    Nonuniversal Effects in the Homogeneous Bose Gas

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    Effective field theory predicts that the leading nonuniversal effects in the homogeneous Bose gas arise from the effective range for S-wave scattering and from an effective three-body contact interaction. We calculate the leading nonuniversal contributions to the energy density and condensate fraction and compare the predictions with results from diffusion Monte Carlo calculations by Giorgini, Boronat, and Casulleras. We give a crude determination of the strength of the three-body contact interaction for various model potentials. Accurate determinations could be obtained from diffusion Monte Carlo calculations of the energy density with higher statistics.Comment: 24 pages, RevTex, 5 ps figures, included with epsf.te

    Dominance and GƗE interaction effects improvegenomic prediction and genetic gain inintermediate wheatgrass (Thinopyrumintermedium)

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    Genomic selection (GS) based recurrent selection methods were developed to accelerate the domestication of intermediate wheatgrass [IWG, Thinopyrum intermedium (Host) Barkworth & D.R. Dewey]. A subset of the breeding population phenotyped at multiple environments is used to train GS models and then predict trait values of the breeding population. In this study, we implemented several GS models that investigated the use of additive and dominance effects and GƗE interaction effects to understand how they affected trait predictions in intermediate wheatgrass. We evaluated 451 genotypes from the University of Minnesota IWG breeding program for nine agronomic and domestication traits at two Minnesota locations during 2017ā€“2018. Genet-mean based heritabilities for these traits ranged from 0.34 to 0.77. Using fourfold cross validation, we observed the highest predictive abilities (correlation of 0.67) in models that considered GƗE effects. When GƗE effects were fitted in GS models, trait predictions improved by 18%, 15%, 20%, and 23% for yield, spike weight, spike length, and free threshing, respectively. Genomic selection models with dominance effects showed only modest increases of up to 3% and were trait-dependent. Crossenvironment predictions were better for high heritability traits such as spike length, shatter resistance, free threshing, grain weight, and seed length than traits with low heritability and large environmental variance such as spike weight, grain yield, and seed width. Our results confirm that GS can accelerate IWG domestication by increasing genetic gain per breeding cycle and assist in selection of genotypes with promise of better performance in diverse environments

    IL-4RĪ± on dendritic cells in neonates and Th2 immunopathology in respiratory syncytial virus infection

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    Ā© Society for Leukocyte Biology. Respiratory syncytial virus (RSV) is one of the leading causes of bronchiolitis in children, and severe RSV infection early in life has been associated with asthma development. Using a neonatal mouse model, we have shown that down-regulation of IL-4 receptor Ī± (IL-4RĪ±) with antisense oligonucleotides in the lung during neonatal infection protected from RSV immunopathophysiology. Significant down-regulation of IL-4RĪ± was observed on pulmonary CD11b+ myeloid dendritic cells (mDCs) suggesting a role for IL-4RĪ± on mDCs in the immunopathogenesis of neonatal RSV infection. Here, we demonstrated that neonatal CD11b+ mDCs expressed higher levels of IL-4RĪ± than their adult counterparts. Because CD11b+ mDCs mainly present antigens to CD4+ T cells, we hypothesized that increased expression of IL- 4RĪ± on neonatal CD11b+ mDCs was responsible for Th2 - biased RSV immunopathophysiology. Indeed, when IL-4RĪ± was selectively deleted from CD11b+ mDCs, the immunopathophysiology typically observed following RSV reinfection was ablated, including Th2 inflammation, airway-mucus hyperproduction, and pulmonary dysfunction. Further, overexpression of IL-4RĪ± on adult CD11b+ DCs and their adoptive transfer into adult mice was able to recapitulate the Th2-biased RSV immunopathology typically observed only in neonates infected with RSV. IL-4RĪ± levels on CD11c+ cells were inversely correlated with maturation status of CD11b+ mDCs upon RSV infection. Our data demonstrate that developmentally regulated IL-4RĪ± expression is critical for the maturity of pulmonary CD11b+ mDCs and the Th2-biased immunopathogenesis of neonatal RSV infection

    Egyptian truffles as a source of antimicrobial and antioxidant agents

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    Edible desert truffles are obligate symbiotic macro hypogenous ascomycetes fruit bodies. These are growing in depth between 5 and 10 cm. These consider a miracle of nature and an unexploited source of therapeutic compounds with antimicrobial, antioxidant, and wonderful food, especially for Bedouins. The current study investigated the activity of premature and mature ethyl acetate truffle extracts (white and Red) collected from the Western Egyptian Desert as antimicrobial and antioxidant. This study evaluated in vitro the efficacy of antimicrobial activity of organic truffles extract, and their effect on various pathogens (Gram-negative, Gram-positive bacteria, filamentous fungi, and yeast) by using agar well diffusion. TEM micrographs had been done for the most effective crude extracts. Furthermore, the activity of DPPH scavenging was studied for both mature truffles. Both truffles extracts had antibacterial activity more than antifungal activity. The selected extracts exhibited an inhibitory effect on the cell wall and protoplasm of pathogens. Terfezia sp. had antioxidant activity more than Tirmania sp. This investigation concluded that the truffle extracts could be considered a promising antibiotic and antioxidant drug in near future

    Cathelicidin suppresses lipid accumulation and hepatic steatosis by inhibition of the CD36 receptor.

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    Background and objectivesObesity is a global epidemic which increases the risk of the metabolic syndrome. Cathelicidin (LL-37 and mCRAMP) is an antimicrobial peptide with an unknown role in obesity. We hypothesize that cathelicidin expression correlates with obesity and modulates fat mass and hepatic steatosis.Materials and methodsMale C57BL/6ā€‰J mice were fed a high-fat diet. Streptozotocin was injected into mice to induce diabetes. Experimental groups were injected with cathelicidin and CD36 overexpressing lentiviruses. Human mesenteric fat adipocytes, mouse 3T3-L1 differentiated adipocytes and human HepG2 hepatocytes were used in the in vitro experiments. Cathelicidin levels in non-diabetic, prediabetic and type II diabetic patients were measured by enzyme-linked immunosorbent assay.ResultsLentiviral cathelicidin overexpression reduced hepatic steatosis and decreased the fat mass of high-fat diet-treated diabetic mice. Cathelicidin overexpression reduced mesenteric fat and hepatic fatty acid translocase (CD36) expression that was reversed by lentiviral CD36 overexpression. Exposure of adipocytes and hepatocytes to cathelicidin significantly inhibited CD36 expression and reduced lipid accumulation. Serum cathelicidin protein levels were significantly increased in non-diabetic and prediabetic patients with obesity, compared with non-diabetic patients with normal body mass index (BMI) values. Prediabetic patients had lower serum cathelicidin protein levels than non-diabetic subjects.ConclusionsCathelicidin inhibits the CD36 fat receptor and lipid accumulation in adipocytes and hepatocytes, leading to a reduction of fat mass and hepatic steatosis in vivo. Circulating cathelicidin levels are associated with increased BMI. Our results demonstrate that cathelicidin modulates the development of obesity

    Primary Breakup of Turbulent Round Liquid Jets in Uniform Crossflows

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77302/1/AIAA-19397-547.pd

    Neutralisation of Local Haemorrhage Induced by the Saw-Scaled Viper Echis carinatus sochureki

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    The objective of the study is to investigate the anti-snake venom activities of a local plant, Hibiscus aethiopicus L. The H. aethiopicus was dried and extracted with ethanol. Different assays were performed according to standard techniques, to evaluate the plantā€™s acute toxicity and its antivenom activities. The results of evaluating the systemic acute toxicity of the H. aethiopicus extract using ā€œoral and intra-peritonealā€ route were normal even at the highest dose (24ā€‰g/kg) tested. All guinea pigs (n=3) when treated with venoms E. c. sochureki (75ā€‰Ī¼g) alone induced acute skin haemorrhage. In contrast, all guinea pigs (n=18) treated with both venom and the plant extract at a concentration between 500 and 1000ā€‰mg/kg showed no signs of haemorrhage. Moreover, all guinea pigs (n=18) treated with venom and the plant extract below 400ā€‰mg/kg showed acute skin haemorrhage. All guinea pigs treated with venom E. c. sochureki (75ā€‰Ī¼g) alone induced acute skin haemorrhage after both 24 and 32 hours. In contrast, all guinea pigs treated with both venom and the plant extract (administered independently) at concentrations between 500 and 1000ā€‰mg/kg showed no signs of haemorrhage after 32 hours. However, after 24 hours all tested guinea pigs showed less inhibition (<60%) compared to that obtained after 32 hours. The outcome of this study reflects that the extract of H. aethiopicus plant may contain an endogenous inhibitor of venom induced local haemorrhage

    Spatial heterogeneity of habitat suitability for Rift Valley fever occurrence in Tanzania: an ecological niche modelling approach

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    Despite the long history of Rift Valley fever (RVF) in Tanzania, extent of its suitable habitat in the country remains unclear. In this study we investigated potential effects of temperature, precipitation, elevation, soil type, livestock density, rainfall pattern, proximity to wild animals, protected areas and forest on the habitat suitability for RVF occurrence in Tanzania. Presence-only records of 193 RVF outbreak locations from 1930 to 2007 together with potential predictor variables were used to model and map the suitable habitats for RVF occurrence using ecological niche modelling. Ground-truthing of the model outputs was conducted by comparing the levels of RVF virus specific antibodies in cattle, sheep and goats sampled from locations in Tanzania that presented different predicted habitat suitability values. Habitat suitability values for RVF occurrence were higher in the northern and central-eastern regions of Tanzania than the rest of the regions in the country. Soil type and precipitation of the wettest quarter contributed equally to habitat suitability (32.4% each), followed by livestock density (25.9%) and rainfall pattern (9.3%). Ground-truthing of model outputs revealed that the odds of an animal being seropositive for RVFV when sampled from areas predicted to be most suitable for RVF occurrence were twice the odds of an animal sampled from areas least suitable for RVF occurrence (95% CI: 1.43, 2.76, p < 0.001). The regions in the northern and central-eastern Tanzania were more suitable for RVF occurrence than the rest of the regions in the country. The modelled suitable habitat is characterised by impermeable soils, moderate precipitation in the wettest quarter, high livestock density and a bimodal rainfall pattern. The findings of this study should provide guidance for the design of appropriate RVF surveillance, prevention and control strategies which target areas with these characteristics
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