158 research outputs found

    SARS-coronavirus-2 replication in Vero E6 cells: replication kinetics, rapid adaptation and cytopathology

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    The sudden emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the end of 2019 from the Chinese province of Hubei and its subsequent pandemic spread highlight the importance of understanding the full molecular details of coronavirus infection and pathogenesis. Here, we compared a variety of replication features of SARS-CoV-2 and SARS-CoV and analysed the cytopathology caused by the two closely related viruses in the commonly used Vero E6 cell line. Compared to SARS-CoV, SARS-CoV-2 generated higher levels of intracellular viral RNA, but strikingly about 50-fold less infectious viral progeny was recovered from the culture medium. lmmunofluorescence microscopy of SARS-CoV-2-infected cells established extensive cross-reactivity of antisera previously raised against a variety of non-structural proteins, membrane and nucleocapsid protein of SARS-CoV. Electron microscopy revealed that the ultrastructural changes induced by the two SARS viruses are very similar and occur within comparable time frames after infection. Furthermore, we determined that the sensitivity of the two viruses to three established inhibitors of coronavirus replication (remdesivir, alisporivir and chloroquine) is very similar, but that SARS-CoV-2 infection was substantially more sensitive to pre-treatment of cells with pegylated interferon alpha. An important difference between the two viruses is the fact that - upon passaging in Vero E6 cells - SARS-CoV-2 apparently is under strong selection pressure to acquire adaptive mutations in its spike protein gene. These mutations change or delete a putative furin-like cleavage site in the region connecting the S1 and S2 domains and result in a very prominent phenotypic change in plaque assays.Microscopic imaging and technolog

    Avaliação da produção de energia de um sistema fotovoltaico instalado na Universidade Presbiteriana Mackenzie – Campus Higienópolis / Evaluation of energy production from a photovoltaic system installed at Mackenzie Presbyterian University – Campus Higienópolis

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    Embora, segundo a Agência Nacional de Energia Elétrica (ANEEL), desde 2016 mais de 40% da energia produzida no Brasil seja de fontes renováveis, e apesar do fluxo de irradiação solar sobre o Brasil ser elevado, menos de 0,04% da energia produzida no Brasil vinha da energia solar em 2016 e atualmente este percentual ainda é baixo, sendo da ordem de 2%. Contribui para isto, não apenas a abundância de recursos hídricos, mas o fato de que a obtenção de energia de placas fotovoltaicas ser  tida como cara e complexa. Visando a melhor compreender as barreiras na implementação de painéis fotovoltaicos para a produção de energia elétrica e de modo a promover a ampliação de seu uso, a Universidade Presbiteriana Mackenzie instalou na laje dos prédios 31 e 33 do campus de Higienópolis em São Paulo, 82 módulos de painéis solares do fabricante Canadian Solar, os quais foram instalados em 4 diferentes arranjos, ocupando uma área de 132 m² da laje. Cada arranjo é composto ou de placas de diferentes tipos ou é formado por placas instaladas com diferentes inclinações, ou seja, com diferentes ângulos de azimute. Neste trabalho, comparam-se os dados medidos de produção de energia elétrica durante os meses de setembro a novembro de 2016 com os valores preditos pelo simulador BlueSol 3.0. A irradiação solar sobre a laje também foi medida. A diferença entre os valores simulados e medidos para a produção de energia nos meses de setembro e outubro foi compatível com a diferença de irradiação solar real e considerada pelo software e também com a limpeza da superfície das placas efetuada no mês de outubro. Observou-se uma maior discrepância entre os valores simulados e preditos no mês de novembro, evidenciando de que há outros fatores, como possivelmente a temperatura das placas e hipóteses de modelagem que causam a divergência entre valores simulados e medidos. Contudo, os desvios não foram elevados, sendo da ordem de no máximo 5%. Neste trabalho, usou-se o software para mostrar como a produção de energia elétrica poderia ser aumentada, obtendo-se um aumento de 6% na produção alterando-se apenas o arranjo dos painéis

    Respective Prognostic Value of Genomic Grade and Histological Proliferation Markers in Early Stage (pN0) Breast Carcinoma

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    Genomic grade (GG) is a 97-gene signature which improves the accuracy and prognostic value of histological grade (HG) in invasive breast carcinoma. Since most of the genes included in the GG are involved in cell proliferation, we performed a retrospective study to compare the prognostic value of GG, Mitotic Index and Ki67 score.A series of 163 consecutive breast cancers was retained (pT1-2, pN0, pM0, 10-yr follow-up). GG was computed using MapQuant Dx(R).GG was low (GG-1) in 48%, high (GG-3) in 31% and equivocal in 21% of cases. For HG-2 tumors, 50% were classified as GG-1, 18% as GG-3 whereas 31% remained equivocal. In a subgroup of 132 ER+/HER2- tumors GG was the most significant prognostic factor in multivariate Cox regression analysis adjusted for age and tumor size (HR = 5.23, p = 0.02).In a reference comprehensive cancer center setting, compared to histological grade, GG added significant information on cell proliferation in breast cancers. In patients with HG-2 carcinoma, applying the GG to guide the treatment scheme could lead to a reduction in adjuvant therapy prescription. However, based on the results observed and considering (i) the relatively close prognostic values of GG and Ki67, (ii) the reclassification of about 30% of HG-2 tumors as Equivocal GG and (iii) the economical and technical requirements of the MapQuant micro-array GG test, the availability in the near future of a PCR-based Genomic Grade test with improved performances may lead to an introduction in clinical routine of this test for histological grade 2, ER positive, HER2 negative breast carcinoma

    Different degrees of malnutrition and immunological alterations according to the aetiology of cirrhosis: a prospective and sequential study

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    OBJECTIVES: In this work we investigated how immunological dysfunction and malnutrition interact in alcoholic and viral aetiologies of cirrhosis. METHODS: To investigate the matter, 77 cirrhotic patients divided in three aetiologies [Alcohol, HCV and Alcohol + HCV) and 32 controls were prospectivelly and sequentially studied. Parameters of humoral immunity (Components 3 and 4 of seric complement and immunoglobulins A M, G and E) and of cellular immunity (total leukocytes and lymphocytes in peripheral blood, T lymphocytes subpopulations, CD4+ and CD8+, CD4+/CD8+ ratio and intradermic tests of delayed hypersensitivity), as well as nutrititional parameters: anthropometric measures, serum albumin and transferrin were evaluated. RESULTS: Multiple statistical comparisons showed that IgM was higher in HCV group; IgG was significantly elevated in both HCV and Alcohol + HCV, whereas for the Alcohol group, IgE was found at higher titles. The analysis of T- lymphocytes subpopulations showed no aetiologic differences, but intradermic tests of delayed hypersensitivity did show greater frequency of anergy in the Alcohol group. For anthropometric parameters, the Alcohol +HCV group displayed the lowest triceps skinfold whereas creatinine – height index evaluation was more preserved in the HCV group. Body mass index, arm muscle area and arm fat area showed that differently from alcohol group, the HCV group was similar to control. CONCLUSION: Significant differences were found among the main aetiologies of cirrhosis concerning immunological alterations and nutritional status: better nutrition and worse immunology for HCV and vice-versa for alcohol

    Sialadenosis in Patients with Advanced Liver Disease

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    Sialadenosis (sialosis) has been associated most often with alcoholic liver disease and alcoholic cirrhosis, but a number of nutritional deficiencies, diabetes, and bulimia have also been reported to result in sialadenosis. The aim of this study was to determine the prevalence of sialadenosis in patients with advanced liver disease. Patients in the study group consisted of 300 candidates for liver transplantation. Types of liver disease in subjects with clinical evidence of sialadenosis were compared with diagnoses in cases who had no manifestations of sialadenosis. The data were analyzed for significant association. Sialadenosis was found in 28 of the 300 subjects (9.3%). Among these 28 cases, 11 (39.3%) had alcoholic cirrhosis. The remaining 17 (60.7%) had eight other types of liver disease. There was no significant association between sialadenosis and alcoholic cirrhosis (P = 0.389). These findings suggest that both alcoholic and non-alcoholic cirrhosis may lead to the development of sialadenosis. Advanced liver disease is accompanied by multiple nutritional deficiencies which may be exacerbated by alcohol. Similar metabolic abnormalities may occur in patients with diabetes or bulimia. Malnutrition has been associated with autonomic neuropathy, the pathogenic mechanism that has been proposed for sialadenosis

    High Mortality of Pneumonia in Cirrhotic Patients with Ascites

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    [[abstract]]Background Cirrhotic patients with ascites are prone to develop various infectious diseases. This study aimed to evaluate the occurrence and effect of major infectious diseases on the mortality of cirrhotic patients with ascites. Methods We reviewed de-identified patient data from the National Health Insurance Database, derived from the Taiwan National Health Insurance Program, to enroll 4,576 cirrhotic patients with ascites, who were discharged from Taiwan hospitals between January 1, 2004 and June 30, 2004. We collected patients’ demographic and clinical data, and reviewed diagnostic codes to determine infectious diseases and comorbid disorders of their hospitalizations. Patients were divided into an infection group and non-infection group and hazard ratios (HR) were determined for specific infectious diseases. Results Of the total 4,576 cirrhotic patients with ascites, 1,294 (28.2%) were diagnosed with infectious diseases during hospitalization. The major infectious diseases were spontaneous bacterial peritonitis (SBP) (645, 49.8%), urinary tract infection (151, 11.7%), and pneumonia (100, 7.7%). After adjusting for patients’ age, gender, and other comorbid disorders, the HRs of infectious diseases for 30-day and 90-day mortality of cirrhotic patients with ascites were 1.81 (1.54-2.11) and 1.60 (1.43-1.80) respectively, compared to those in the non-infection group. The adjusted HRs of pneumonia, urinary tract infection (UTI), spontaneous bacterial peritonitis (SBP), and sepsis without specific focus (SWSF) were 2.95 (2.05-4.25), 1.32 (0.86-2.05), 1.77 (1.45-2.17), and 2.19 (1.62-2.96) for 30-day mortality, and 2.57 (1.93-3.42), 1.36 (1.01-1.82), 1.51 (1.29-1.75), and 2.13 (1.70-2.66) for 90-day mortality, compared to those in the non-infection group. Conclusion Infectious diseases increased 30-day and 90-day mortality of cirrhotic patients with ascites. Among all infectious diseases identified, pneumonia carried the highest risk for mortality.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]電子

    Ki-67 as prognostic marker in early breast cancer: a meta-analysis of published studies involving 12 155 patients

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    The Ki-67 antigen is used to evaluate the proliferative activity of breast cancer (BC); however, Ki-67's role as a prognostic marker in BC is still undefined. In order to better define the prognostic value of Ki-67/MIB-1, we performed a meta-analysis of studies that evaluated the impact of Ki-67/MIB-1 on disease-free survival (DFS) and/or on overall survival (OS) in early BC. Sixty-eight studies were identified and 46 studies including 12 155 patients were evaluable for our meta-analysis; 38 studies were evaluable for the aggregation of results for DFS, and 35 studies for OS. Patients were considered to present positive tumours for the expression of Ki-67/MIB-1 according to the cut-off points defined by the authors. Ki-67/MIB-1 positivity is associated with higher probability of relapse in all patients (HR=1.93 (95% confidence interval (CI): 1.74–2.14); P<0.001), in node-negative patients (HR=2.31 (95% CI: 1.83–2.92); P<0.001) and in node-positive patients (HR=1.59 (95% CI: 1.35–1.87); P<0.001). Furthermore, Ki-67/MIB-1 positivity is associated with worse survival in all patients (HR=1.95 (95% CI: 1.70–2.24; P<0.001)), node-negative patients (HR=2.54 (95% CI: 1.65–3.91); P<0.001) and node-positive patients (HR=2.33 (95% CI: 1.83–2.95); P<0.001). Our meta-analysis suggests that Ki-67/MIB-1 positivity confers a higher risk of relapse and a worse survival in patients with early BC

    Dimerisation induced formation of the active site and the identification of three metal sites in EAL-phosphodiesterases

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    The bacterial second messenger cyclic di-3′,5′-guanosine monophosphate (c-di-GMP) is a key regulator of bacterial motility and virulence. As high levels of c-di-GMP are associated with the biofilm lifestyle, c-di-GMP hydrolysing phosphodiesterases (PDEs) have been identified as key targets to aid development of novel strategies to treat chronic infection by exploiting biofilm dispersal. We have studied the EAL signature motif-containing phosphodiesterase domains from the Pseudomonas aeruginosa proteins PA3825 (PA3825EAL) and PA1727 (MucREAL). Different dimerisation interfaces allow us to identify interface independent principles of enzyme regulation. Unlike previously characterised two-metal binding EAL-phosphodiesterases, PA3825EAL in complex with pGpG provides a model for a third metal site. The third metal is positioned to stabilise the negative charge of the 5′-phosphate, and thus three metals could be required for catalysis in analogy to other nucleases. This newly uncovered variation in metal coordination may provide a further level of bacterial PDE regulation

    Chemical genetics strategy identifies an HCV NS5A inhibitor with a potent clinical effect. Nature

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    The worldwide prevalence of chronic hepatitis C virus (HCV) infection is estimated to be approaching 200 million people We designed a mechanistically unbiased approach based on chemical genetics to identify chemical starting points for interfering with HCV replication. Our differentiating strategy centred on the identification of compounds functionally distinct from those acting on the traditional targets of antiviral research in this field, the NS3 protease and the NS5B RNA-dependent RNA polymerase 10 . BMS-858 formed the basis of an extensive series of chemical refinements that focused on improving antiviral potency, broadening inhibitory activity to encompass the HCV 1a genotype, and optimizing for oral bioavailability and sustained pharmacokinetic properties. After defining symmetry as an important contributor to antiviral activity 10 , a discovery that preceded the disclosure of structural information (see below), we subsequently identified BMS-79005

    SARS-CoV-2 variants of interest and concern naming scheme conducive for global discourse

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    A group convened and led by the Virus Evolution Working Group of the World Health Organization reports on its deliberations and announces a naming scheme that will enable clear communication about SARS-CoV-2 variants of interest and concern.Molecular basis of virus replication, viral pathogenesis and antiviral strategie
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