290 research outputs found
Overview of Membrane Science and Technology in Portugal
Funding Information: Acknowledgments: The authors acknowledge Tiago AraĂșjo for his valuable contribution in writingâoriginal draft preparationâthe carbon molecular sieve membranes content. LCT is grateful to Fundação para a CiĂȘncia e a Tecnologia (FCT/MCTES) for her assistant researcher contract under Scientific Employment Stimulus (2020.01555.CEECIND). DMFS thanks FCT/MCTES for a research contract in the scope of programmatic funding UIDP/04540/2020. Funding Information: Funding: This work was supported by Associate Laboratory for Green ChemistryâLAQV, which is financed by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/50006/2020), Research project PTDC/EQU-EPQ/29579/2017 funded by FCT/MCTES âPrograma Operacional Regional de Lisboa, FEDERâ, project Nanoart PTDC/CTM-BIO/6178/2014 and CeFEMA with grant number 325UID/CTM/04540/2013 funded by FCT/MCTES. Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Membrane research in Portugal is aligned with global concerns and expectations for sustainable social development, thus progressively focusing on the use of natural resources and renewable energy. This review begins by addressing the pioneer work on membrane science and technology in Portugal by the research groups of Instituto Superior TĂ©cnicoâUniversidade de Lisboa (IST), NOVA School of Science and TechnologyâUniversidade Nova de Lisboa (FCT NOVA) and Faculdade de EngenhariaâUniversidade do Porto (FEUP) aiming to provide an historical perspective on the topic. Then, an overview of the trends and challenges in membrane processes and materials, mostly in the last five years, involving Portuguese researchers, is presented as a contribution to a more sustainable waterâenergyâmaterialâfood nexus.publishersversionpublishe
Environmental risk factors of type 2 diabetes-an exposome approach
Type 2 diabetes is one of the major chronic diseases accounting for a substantial proportion of disease burden in Western countries. The majority of the burden of type 2 diabetes is attributed to environmental risks and modifiable risk factors such as lifestyle. The environment we live in, and changes to it, can thus contribute substantially to the prevention of type 2 diabetes at a population level. The âexposomeâ represents the (measurable) totality of environmental, i.e. nongenetic, drivers of health and disease. The external exposome comprises aspects of the built environment, the social environment, the physico-chemical environment and the lifestyle/food environment. The internal exposome comprises measurements at the epigenetic, transcript, proteome, microbiome or metabolome level to study either the exposures directly, the imprints these exposures leave in the biological system, the potential of the body to combat environmental insults and/or the biology itself. In this review, we describe the evidence for environmental risk factors of type 2 diabetes, focusing on both the general external exposome and imprints of this on the internal exposome. Studies provided established associations of air pollution, residential noise and area-level socioeconomic deprivation with an increased risk of type 2 diabetes, while neighbourhood walkability and green space are consistently associated with a reduced risk of type 2 diabetes. There is little or inconsistent evidence on the contribution of the food environment, other aspects of the social environment and outdoor temperature. These environmental factors are thought to affect type 2 diabetes risk mainly through mechanisms incorporating lifestyle factors such as physical activity or diet, the microbiome, inflammation or chronic stress. To further assess causality of these associations, future studies should focus on investigating the longitudinal effects of our environment (and changes to it) in relation to type 2 diabetes risk and whether these associations are explained by these proposed mechanisms. Graphical abstract: [Figure not available: see fulltext.
Structural studies of Helicase NS3 variants from Hepatitis C virus genotype 3 in virological sustained responder and non-responder patients
<p>Abstract</p> <p>Background</p> <p>About 130 million people are infected with the hepatitis C virus (HCV) worldwide, but effective treatment options are not yet available. One of the most promising targets for antiviral therapy is nonstructural protein 3 (NS3). To identify possible changes in the structure of NS3 associated with virological sustained response or non-response of patients, a model was constructed for each helicase NS3 protein coding sequence. From this, the goal was to verify the interaction between helicases variants and their ligands.</p> <p>Findings</p> <p>Evidence was found that the NS3 helicase portion of non-responder patients contained substitutions in its ATP and RNA binding sites. K210E substitution can cause an imbalance in the distribution of loads, leading to a decrease in the number of ligations between the essential amino acids required for the hydrolysis of ATP. W501R substitution causes an imbalance in the distribution of loads, leading and forcing the RNA to interact with the amino acid Thr269, but not preventing binding of ribavirin inhibitor.</p> <p>Conclusions</p> <p>Useful information is provided on the genetic profiling of the HCV genotype 3, specifically the coding region of the NS3 protein, improving our understanding of the viral genome and the regions of its protein catalytic site.</p
A Rapid and Simple Procedure for the Establishment of Human Normal and Cancer Renal Primary Cell Cultures from Surgical Specimens
The kidney is a target organ for the toxicity of several xenobiotics and is also highly susceptible to the development of malignant tumors. In both cases, in vitro studies provide insight to cellular damage, and represent adequate models to study either the mechanisms underlying the toxic effects of several nephrotoxicants or therapeutic approaches in renal cancer. The development of efficient methods for the establishment of human normal and tumor renal cell models is hence crucial. In this study, a technically simple and rapid protocol for the isolation and culture of human proximal tubular epithelial cells and human renal tumor cells from surgical specimens is presented. Tumor and normal tissues were processed by using the same methodology, based on mechanical disaggregation of tissue followed by enzymatic digestion and cell purification by sequential sieving. The overall procedure takes roughly one hour. The resulting cell preparations have excellent viabilities and yield. Establishment of primary cultures from all specimens was achieved successfully. The origin of primary cultured cells was established through morphological evaluation. Normal cells purity was confirmed by immunofluorescent staining and reverse transcription-polymerase chain reaction analysis for expression of specific markers
Genomics and epidemiology of the P.1 SARS-CoV-2 lineage in Manaus, Brazil
Cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Manaus, Brazil, resurged in late 2020 despite previously high levels of infection. Genome sequencing of viruses sampled in Manaus between November 2020 and January 2021 revealed the emergence and circulation of a novel SARS-CoV-2 variant of concern. Lineage P.1 acquired 17 mutations, including a trio in the spike protein (K417T, E484K, and N501Y) associated with increased binding to the human ACE2 (angiotensin-converting enzyme 2) receptor. Molecular clock analysis shows that P.1 emergence occurred around mid-November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.7- to 2.4-fold more transmissible and that previous (non-P.1) infection provides 54 to 79% of the protection against infection with P.1 that it provides against non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness
Denitrification coupled with methane anoxic oxidation and microbial community involved identification
Genetic diversity of NS5A protein from hepatitis C virus genotype 3a and its relationship to therapy response
<p>Abstract</p> <p>Background</p> <p>The quasispecies nature of HCV may have important implications for viral persistence, pathogenicity and resistance to antiviral agents. The variability of one of the viral proteins, NS5A, is believed to be related to the response to IFN therapy, the standard treatment for infection. In this study we analyzed the quasispecies composition of NS5A protein in patients infected with HCV genotype 3a, before IFN therapy.</p> <p>Methods</p> <p>Viral RNA was isolated from samples of 12 patients: four sustained virological responders (SVR), four non-responders (NR), and four end-of-treatment responders (ETR). cDNA was synthesized, the NS5A region was amplified and the fragments obtained were cloned. Fifteen clones from each patient were sequenced with eight primers, generating 179 contigs.</p> <p>Results</p> <p>Higher values for substitution (either synonymous or non-synonymous) and for distance were found in the SVR group. However, the NR group showed relatively more non-synonymous mutations than the other groups, owing to the higher values of dN/dS in complete NS5A and most specific regions. Overall, NS5A protein is undergoing purifying selection, since all dN/dS ratios values are below 0.5.</p> <p>Conclusions</p> <p>Our study provides an overview of the genetic variability of complete NS5A protein in HCV genotype 3a.</p
Predictors of HBeAg status and hepatitis B viraemia in HIV-infected patients with chronic hepatitis B in the HAART era in Brazil
<p>Abstract</p> <p>Background</p> <p>HBV-HIV co-infection is associated with an increased liver-related morbidity and mortality. However, little is known about the natural history of chronic hepatitis B in HIV-infected individuals under highly active antiretroviral therapy (HAART) receiving at least one of the two drugs that also affect HBV (TDF and LAM). Information about HBeAg status and HBV viremia in HIV/HBV co-infected patients is scarce. The objective of this study was to search for clinical and virological variables associated with HBeAg status and HBV viremia in patients of an HIV/HBV co-infected cohort.</p> <p>Methods</p> <p>A retrospective cross-sectional study was performed, of HBsAg-positive HIV-infected patients in treatment between 1994 and 2007 in two AIDS outpatient clinics located in the SĂŁo Paulo metropolitan area, Brazil. The baseline data were age, sex, CD4 T+ cell count, ALT level, HIV and HBV viral load, HBV genotype, and duration of antiretroviral use. The variables associated to HBeAg status and HBV viremia were assessed using logistic regression.</p> <p>Results</p> <p>A total of 86 HBsAg patients were included in the study. Of these, 48 (56%) were using combination therapy that included lamivudine (LAM) and tenofovir (TDF), 31 (36%) were using LAM monotherapy, and 7 patients had no previous use of either one. Duration of use of TDF and LAM varied from 4 to 21 and 7 to 144 months, respectively. A total of 42 (48. 9%) patients were HBeAg positive and 44 (51. 1%) were HBeAg negative. The multivariate analysis revealed that the use of TDF for longer than 12 months was associated with undetectable HBV DNA viral load (serum HBV DNA level < 60 UI/ml) (<it>p </it>= 0. 047). HBeAg positivity was associated with HBV DNA > 60 UI/ml (p = 0. 001) and ALT levels above normality (<it>p </it>= 0. 038).</p> <p>Conclusion</p> <p>Prolonged use of TDF containing HAART is associated with undetectable HBV DNA viral load. HBeAg positivity is associated with HBV viremia and increased ALT levels.</p
A percepção profissional e comunitåria sobre a reinserção social dos usuårios de drogas
O processo de reinserção social de usuĂĄrios de substĂąncias psicoativas tem se configurado como uma das principais estratĂ©gias da PolĂtica Nacional sobre Drogas. Haja vista que o uso de substĂąncias emerge como um dos principais problemas de saĂșde pĂșblica na atualidade, o presente artigo teve como objetivo compreender as percepçÔes dos atores sociais inseridos nas polĂticas da saĂșde, assistĂȘncia social e lideranças comunitĂĄrias acerca do processo de reinserção social dos usuĂĄrios de drogas. Trata-se de uma pesquisa de cunho qualitativo, onde foram realizadas doze entrevistas semiestruturadas com diferentes informantes-chave, inseridos em um territĂłrio com elevados indicadores de uso de drogas. Os resultados apontam para os desafios no processo de inserção efetiva dos usuĂĄrios de drogas em razĂŁo da existĂȘncia de uma rede assistencial multissetorial, um profundo processo de estigmatização social, a naturalização do uso de drogas, a responsabilização da famĂlia, alĂ©m da sobrecarga de trabalho nas polĂticas pĂșblicas
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