14 research outputs found

    The Histone H3K79 Methyltransferase Dot1L Is Essential for Mammalian Development and Heterochromatin Structure

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    Dot1 is an evolutionarily conserved histone methyltransferase specific for lysine 79 of histone H3 (H3K79). In Saccharomyces cerevisiae, Dot1-mediated H3K79 methylation is associated with telomere silencing, meiotic checkpoint control, and DNA damage response. The biological function of H3K79 methylation in mammals, however, remains poorly understood. Using gene targeting, we generated mice deficient for Dot1L, the murine Dot1 homologue. Dot1L-deficient embryos show multiple developmental abnormalities, including growth impairment, angiogenesis defects in the yolk sac, and cardiac dilation, and die between 9.5 and 10.5 days post coitum. To gain insights into the cellular function of Dot1L, we derived embryonic stem (ES) cells from Dot1L mutant blastocysts. Dot1L-deficient ES cells show global loss of H3K79 methylation as well as reduced levels of heterochromatic marks (H3K9 di-methylation and H4K20 tri-methylation) at centromeres and telomeres. These changes are accompanied by aneuploidy, telomere elongation, and proliferation defects. Taken together, these results indicate that Dot1L and H3K79 methylation play important roles in heterochromatin formation and in embryonic development

    HIV-1 gp120 Induces Expression of IL-6 through a Nuclear Factor-Kappa B-Dependent Mechanism: Suppression by gp120 Specific Small Interfering RNA

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    In addition to its role in virus entry, HIV-1 gp120 has also been implicated in HIV-associated neurocognitive disorders. However, the mechanism(s) responsible for gp120-mediated neuroinflammation remain undefined. In view of increased levels of IL-6 in HIV-positive individuals with neurological manifestations, we sought to address whether gp120 is involved in IL-6 over-expression in astrocytes. Transfection of a human astrocyte cell line with a plasmid encoding gp120 resulted in increased expression of IL-6 at the levels of mRNA and protein by 51.3±2.1 and 11.6±2.2 fold respectively; this effect of gp120 on IL-6 expression was also demonstrated using primary human fetal astrocytes. A similar effect on IL-6 expression was observed when primary astrocytes were treated with gp120 protein derived from different strains of X4 and R5 tropic HIV-1. The induction of IL-6 could be abrogated by use of gp120-specific siRNA. Furthermore, this study showed that the NF-κB pathway is involved in gp120-mediated IL-6 over-expression, as IKK-2 and IKKβ inhibitors inhibited IL-6 expression by 56.5% and 60.8%, respectively. These results were also confirmed through the use of NF-κB specific siRNA. We also showed that gp120 could increase the phosphorylation of IκBα. Furthermore, gp120 transfection in the SVGA cells increased translocation of NF-κB from cytoplasm to nucleus. These results demonstrate that HIV-1 gp120-mediated over-expression of IL-6 in astrocytes is one mechanism responsible for neuroinflammation in HIV-infected individuals and this is mediated by the NF-κB pathway

    Cotton in the new millennium: advances, economics, perceptions and problems

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    Cotton is the most significant natural fibre and has been a preferred choice of the textile industry and consumers since the industrial revolution began. The share of man-made fibres, both regenerated and synthetic fibres, has grown considerably in recent times but cotton production has also been on the rise and accounts for about half of the fibres used for apparel and textile goods. To cotton’s advantage, the premium attached to the presence of cotton fibre and the general positive consumer perception is well established, however, compared to commodity man-made fibres and high performance fibres, cotton has limitations in terms of its mechanical properties but can help to overcome moisture management issues that arise with performance apparel during active wear. This issue of Textile Progress aims to: i. Report on advances in cotton cultivation and processing as well as improvements to conventional cotton cultivation and ginning. The processing of cotton in the textile industry from fibre to finished fabric, cotton and its blends, and their applications in technical textiles are also covered. ii. Explore the economic impact of cotton in different parts of the world including an overview of global cotton trade. iii. Examine the environmental perception of cotton fibre and efforts in organic and genetically-modified (GM) cotton production. The topic of naturally-coloured cotton, post-consumer waste is covered and the environmental impacts of cotton cultivation and processing are discussed. Hazardous effects of cultivation, such as the extensive use of pesticides, insecticides and irrigation with fresh water, and consequences of the use of GM cotton and cotton fibres in general on the climate are summarised and the effects of cotton processing on workers are addressed. The potential hazards during cotton cultivation, processing and use are also included. iv. Examine how the properties of cotton textiles can be enhanced, for example, by improving wrinkle recovery and reducing the flammability of cotton fibre

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Relevance of ratio of neck circumference to thyromental distance in predicting difficult intubation

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    Background and Objectives: Airway assessment is the most important aspect of anaesthetic practice as a difficult intubation may be unanticipated. A study was done to know the relevance of ratio of neck circumference to thyromental distance in predicting difficult intubation in general Indian population coming for surgery. Materials and methods: 500 Patients with ASA PS I& II were enrolled in the study were preoperatively assessed for airway parameters such as Modified mallampati classification, thyromental distance, sternomental distance, neck circumference to thyromental distance ratio and Wilson score. Intra-operatively all patients were classified according to Cormack and Lehane laryngoscopic view. Results: The mean age, Weight, Height and BMI of patients in our study was 34.43 years, 61.07 kg,69.2cms and 21.2 respectively. In our study we had a total of 15 difficult intubation with all of them belonging to Cormack-Lehane grade III. In our study we noted that among 15 patients with CLIII/IV only 4 had a SMD≤15.75 cm. With that we noted a sensitivity, specificity, PPV and NPV of 26.7%,75.1%,3.2% and 97.1%. Among 15 patients with CLIII/IV only 2 of them had Wilson score of more than 3.&nbsp

    Preoperative ultrasound guided inferior venacava collapsibility index as a guide to predict hypotension following spinal anaesthesia in patients scheduled for elective surgery

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    Background: Spinal anaesthesia is the most commonly employed anaesthetic technique for infraumbilical surgeries. Post spinal hypotension is a commonly encountered complication which can lead to organ under perfusion and ischemia. Severe episodes of intraoperative hypotension have been proposed as an independent risk factorin the development of postoperative adverse outcomes and prolonged hospital stay. However, there are no reliable methods to determine which patients are at risk for spinal induced hypotension. This study investigated whether preoperative ultrasound guided inferior venacava collapsibility index (IVC-CI) could predict hypotension following spinal anaesthesia. Objectives were to measure inferior venacava collapsibility index and to compare the incidence of hypotension following spinal anaesthesia among patients with IVC-CI>50% and patients with IVC-CI<50%. Materials and Methods: This prospective observational study was conducted in the department of anaesthesia, Yenepoya Medical College Hospital, Mangalore during the period between October 2016 to October 2018. After ethical committee approval and informed consent, 73 patients belonging to “American society of Anesthesiology” (ASA) grade I & II, aged between 18 to 65 years, scheduled for elective surgeries which require spinal anaesthesia were selected. Preoperative ultrasonography was done to determine the IVC-CI in these patients. All ultrasonographic examinations were performed by the same anaesthesiologist.&nbsp

    3rd National Conference on Image Processing, Computing, Communication, Networking and Data Analytics

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    This volume contains contributed articles presented in the conference NCICCNDA 2018, organized by the Department of Computer Science and Engineering, GSSS Institute of Engineering and Technology for Women, Mysore, Karnataka (India) on 28th April 2018
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