1,874 research outputs found

    Identification of novel subgroup a variants with enhanced receptor binding and replicative capacity in primary isolates of anaemogenic strains of feline leukaemia virus

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    <b>BACKGROUND:</b> The development of anaemia in feline leukaemia virus (FeLV)-infected cats is associated with the emergence of a novel viral subgroup, FeLV-C. FeLV-C arises from the subgroup that is transmitted, FeLV-A, through alterations in the amino acid sequence of the receptor binding domain (RBD) of the envelope glycoprotein that result in a shift in the receptor usage and the cell tropism of the virus. The factors that influence the transition from subgroup A to subgroup C remain unclear, one possibility is that a selective pressure in the host drives the acquisition of mutations in the RBD, creating A/C intermediates with enhanced abilities to interact with the FeLV-C receptor, FLVCR. In order to understand further the emergence of FeLV-C in the infected cat, we examined primary isolates of FeLV-C for evidence of FeLV-A variants that bore mutations consistent with a gradual evolution from FeLV-A to FeLV-C.<p></p> <b>RESULTS:</b> Within each isolate of FeLV-C, we identified variants that were ostensibly subgroup A by nucleic acid sequence comparisons, but which bore mutations in the RBD. One such mutation, N91D, was present in multiple isolates and when engineered into a molecular clone of the prototypic FeLV-A (Glasgow-1), enhanced replication was noted in feline cells. Expression of the N91D Env on murine leukaemia virus (MLV) pseudotypes enhanced viral entry mediated by the FeLV-A receptor THTR1 while soluble FeLV-A Env bearing the N91D mutation bound more efficiently to mouse or guinea pig cells bearing the FeLV-A and -C receptors. Long-term in vitro culture of variants bearing the N91D substitution in the presence of anti-FeLV gp70 antibodies did not result in the emergence of FeLV-C variants, suggesting that additional selective pressures in the infected cat may drive the subsequent evolution from subgroup A to subgroup C.<p></p> <b>CONCLUSIONS:</b> Our data support a model in which variants of FeLV-A, bearing subtle differences in the RBD of Env, may be predisposed towards enhanced replication in vivo and subsequent conversion to FeLV-C. The selection pressures in vivo that drive the emergence of FeLV-C in a proportion of infected cats remain to be established

    Smart homes and their users:a systematic analysis and key challenges

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    Published research on smart homes and their users is growing exponentially, yet a clear understanding of who these users are and how they might use smart home technologies is missing from a field being overwhelmingly pushed by technology developers. Through a systematic analysis of peer-reviewed literature on smart homes and their users, this paper takes stock of the dominant research themes and the linkages and disconnects between them. Key findings within each of nine themes are analysed, grouped into three: (1) views of the smart home-functional, instrumental, socio-technical; (2) users and the use of the smart home-prospective users, interactions and decisions, using technologies in the home; and (3) challenges for realising the smart home-hardware and software, design, domestication. These themes are integrated into an organising framework for future research that identifies the presence or absence of cross-cutting relationships between different understandings of smart homes and their users. The usefulness of the organising framework is illustrated in relation to two major concerns-privacy and control-that have been narrowly interpreted to date, precluding deeper insights and potential solutions. Future research on smart homes and their users can benefit by exploring and developing cross-cutting relationships between the research themes identified

    Coxiella burnetii Phagocytosis Is Regulated by GTPases of the Rho Family and the RhoA Effectors mDia1 and ROCK

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    The GTPases belonging to the Rho family control the actin cytoskeleton rearrangements needed for particle internalization during phagocytosis. ROCK and mDia1 are downstream effectors of RhoA, a GTPase involved in that process. Coxiella burnetii, the etiologic agent of Q fever, is internalized by the host´s cells in an actin-dependent manner. Nevertheless, the molecular mechanism involved in this process has been poorly characterized. This work analyzes the role of different GTPases of the Rho family and some downstream effectors in the internalization of C. burnetii by phagocytic and non-phagocytic cells. The internalization of C. burnetii into HeLa and RAW cells was significantly inhibited when the cells were treated with Clostridium difficile Toxin B which irreversibly inactivates members of the Rho family. In addition, the internalization was reduced in HeLa cells that overexpressed the dominant negative mutants of RhoA, Rac1 or Cdc42 or that were knocked down for the Rho GTPases. The pharmacological inhibition or the knocking down of ROCK diminished bacterium internalization. Moreover, C. burnetii was less efficiently internalized in HeLa cells overexpressing mDia1-N1, a dominant negative mutant of mDia1, while the overexpression of the constitutively active mutant mDia1-ΔN3 increased bacteria uptake. Interestingly, when HeLa and RAW cells were infected, RhoA, Rac1 and mDia1 were recruited to membrane cell fractions. Our results suggest that the GTPases of the Rho family play an important role in C. burnetii phagocytosis in both HeLa and RAW cells. Additionally, we present evidence that ROCK and mDia1, which are downstream effectors of RhoA, are involved in that processFil: Salinas Ojeda, Romina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Ortiz Flores, Rodolfo Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Distel, Jesús Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Aguilera, Milton Osmar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Colombo, Maria Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Beron, Walter. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentin

    An Evidence Quality Assessment Model for Cyber Security Policymaking

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    A key factor underpinning a state’s capacity to respond to cyber security policy challenges is the quality of evidence that supports decision making. As part of this process, policy advisers, essentially a diverse group that includes everyone from civil servants to elected policy makers, are required to assess evidence from a mix of sources. In time-critical scenarios where relevant expertise is limited or not available, assessing threats, risk and proportionate response based on official briefings, academic sources and industry threat reports can be very challenging. This chapter presents a model for assessing the quality of evidence used in policymaking. The utility of the model is illustrated using a sample of evidence sources and it is demonstrated how different attributes may be used for comparing evidence quality. The ultimate goal is to help resolve potential conflicts and weigh findings and opinions in a systematic manner

    Efektivitas Traditional Massage dan Swedish Massage Dalam Menurunkan Tingkat Kelelahan dan Meningkatkan Kualitas Tidur Pada Pekerja Pasca Covid-19

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    Penelitian ini bertujuan untuk mengetahui (1) efektivitas traditional massage dalam menurunkan tingkat kelelahan dan meningkatkan kualitas tidur pada pekerja pasca covid-19, (2) efektivitas Swedish massage dalam menurunkan tingkat kelelahan dan meningkatkan kualitas tidur pada pekerja pasca covid-19, (3) Mengetahui perbandingan efektivitas antara metode traditional massage dan Swedish massage dalam menurunkan tingkat kelelahan dan meningkatkan kualitas tidur pada pekerja pasca covid-19. Penelitian ini merupakan penelitian eksperimen semu dengan menggunakan two group experiment design. Model penelitian menggunakan dua kelompok sampel berbeda dengan perlakuan yang berbeda pula. Sampel penelitian merupakan pekerja pasca covid-19 yang mengalami kelelahan dan kualitas tidur buruk berjumlah 40 orang yang dibagi menjadi dua kelompok secara random berjumlah 20 orang. Kelompok A menggunakan metode traditional massage dan kelompok B menggunakan metode Swedish massage. Perlakuan dilakukan sebanyak satu kali perlakuan dengan durasi 45 menit. Pengukuran tingkat kelelahan menggunakan instrumen Fatigue Severty Scale, kualitas tidur menggunakan instrument Kuesioner Kualitas Tidur (KKT). Teknik analisis data menggunakan uji normalitas, homogenitas, dan uji beda (paired t test dan independent t test). Hasil penelitian menunjukan bahwa metode traditional massage maupun Swedish massage dapat menurunkan tingkat kelelahan dan meningkatkan kualitas tidur secara signifikan dengan nilai p0,05, sehingga disimpulkan bahwa kedua jenis perlakuan tidak memiliki perbedaan yang signifikan

    Performance of the CMS Cathode Strip Chambers with Cosmic Rays

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    The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

    Predicting Physical Time Series Using Dynamic Ridge Polynomial Neural Networks

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    Forecasting naturally occurring phenomena is a common problem in many domains of science, and this has been addressed and investigated by many scientists. The importance of time series prediction stems from the fact that it has wide range of applications, including control systems, engineering processes, environmental systems and economics. From the knowledge of some aspects of the previous behaviour of the system, the aim of the prediction process is to determine or predict its future behaviour. In this paper, we consider a novel application of a higher order polynomial neural network architecture called Dynamic Ridge Polynomial Neural Network that combines the properties of higher order and recurrent neural networks for the prediction of physical time series. In this study, four types of signals have been used, which are; The Lorenz attractor, mean value of the AE index, sunspot number, and heat wave temperature. The simulation results showed good improvements in terms of the signal to noise ratio in comparison to a number of higher order and feedforward neural networks in comparison to the benchmarked techniques

    Expression of M. tuberculosis-induced suppressor of cytokine signaling (SOCS) 1, SOCS3, FoxP3 and secretion of IL-6 associates with differing clinical severity of tuberculosis

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    Background Appropriate immune activation of T cells and macrophages is central for the control of Mycobacterium tuberculosis infections. IFN-γ stimulated responses are lowered in tuberculosis (TB), while expression of Suppressor of Cytokine Signaling (SOCS) molecules – 1 and 3 and CD4+CD25+FoxP3+T regulatory cells is increased. Here we investigated the association of these molecules in regard to clinical severity of TB. Methods Peripheral blood mononuclear cells (PBMCs) were isolated from patients with pulmonary TB (PTB, n = 33), extra-pulmonary TB (ETB, n = 33) and healthy endemic controls (EC, n = 15). Cases were classified as moderately advanced or far advanced PTB, and less severe or severe disseminated ETB. M. tuberculosis -stimulated IFN-γ, SOCS1, SOCS3 and FoxP3 gene expression and secretion of Th1 and Th2 cytokines was measured. Statistical analysis was performed using Mann–Whitney U, Wilcoxon Rank and Kruskal Wallis non-parametric tests. Results In un-stimulated PBMCs, IL-6 (p = 0.018) and IL-10 (p = 0.013) secretion levels were increased in PTB while IL-10 was also increased in ETB (p = 0.003), all in comparison with EC. M. tuberculosis-stimulated IL-6 (p = 0.003) was lowered in ETB as compared with EC. SOCS1 mRNA expression in M. tuberculosis stimulated PBMCs levels in moderately advanced PTB (p = 0.022), far advanced (p = 0.014) PTB, and severe ETB (p = 0.009) were raised as compared with EC. On the other hand, SOCS1 mRNA titers were reduced in less severe ETB, in comparison with severe ETB (p = 0.027) and far advanced PTB (p = 0.016). SOCS3 mRNA accumulation was reduced in far advanced PTB (p = 0.007) and FoxP3 mRNA expression was increased in less severe ETB as compared with EC (p = 0.017). Conclusions The lowered SOCS1 mRNA levels in patients with less severe extra-pulmonary TB as compared to those with more severe ETB and PTB may lead to elevated IFN-γ pathway gene expression in the latter group. As localized ETB has shown to be associated with more effective Th1 immunity and adaptive responses, this suggests a role for SOCS1 in determining disease outcome in extra-pulmonary TB

    Impact of Consanguinity, Environment, Socio-Economic and Other Risk Factors on Epidemiology of Leukemia

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    The study was aimed to investigate the occurrence and prevalence of leukemia in a hospital population and the impact of consanguinity, surname, birth order, blood group, family history, environment, socioeconomic and smoking characteristics on the occurrence of leukemia. A standard questionnaire was used to collect information including different parameters like age, sex, birth order, exact diagnosis, genetic relationships, education, socioeconomic status, smoking, physical activities, allied diseases, locality and family history of patients. Chronic myeloid leukemia (CML) was most commonly occurring malignancy 42.28% followed by Acute lymphoid leukemia (ALL) 26.18%, Acute myeloid leukemia (AML) 16.11% and Chronic lymphoid leukemia (CLL) 15.43%. There was a significant (P< 0.05) gender depicted difference in prevalence of leukemia. The patients with blood group O+ (29.53%) were more affected with Leukemia. 4th Birth order (16.78%) showed the highest affliction of all leukemia conditions. Rural (62.42%) population was significantly influenced than urban (37.58%) population (P<0.05). Patients with low level of education were more affected (P< 0.01) with leukemia than highly educated patients. In this study outcomes of first cousin marriages resulted in higher leukemia affliction than outcomes of unrelated couples. The inbreeding coefficient was also observed high (F=0.0267), which indicates genetic basis of leukemia. Highest percentage of patients among various surnames was observed in Arian (29.53%) and lowest in Mughal (1.35%). Smoking was important risk factor for occurrence of leukemia. It was found that 59.73% patients belonged to the lower class followed by middle class (35.57%) and 4.70% in upper class. The study of the risk factors leading to leukemia is pertinent and would help to identify strategies to develop protective policies and interventions
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