26 research outputs found

    Heterologous Expression of the Phytochelatin Synthase CaPCS2 from Chlamydomonas acidophila and Its Effect on Different Stress Factors in Escherichia coli

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    Phytochelatins (PCs) are cysteine-rich small peptides, enzymatically synthesized from reduced glutathione (GSH) by cytosolic enzyme phytochelatin synthase (PCS). The open reading frame (ORF) of the phytochelatin synthase CaPCS2 gene from the microalgae Chlamydomonas acidophila was heterologously expressed in Escherichia coli strain DH5 alpha, to analyze its role in protection against various abiotic agents that cause cellular stress. The transformed E. coli strain showed increased tolerance to exposure to different heavy metals (HMs) and arsenic (As), as well as to acidic pH and exposure to UVB, salt, or perchlorate. In addition to metal detoxification activity, new functions have also been reported for PCS and PCs. According to the results obtained in this work, the heterologous expression of CaPCS2 in E. coli provides protection against oxidative stress produced by metals and exposure to different ROS-inducing agents. However, the function of this PCS is not related to HM bioaccumulation

    Novel Genes Involved in Resistance to Both Ultraviolet Radiation and Perchlorate From the Metagenomes of Hypersaline Environments

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    Microorganisms that thrive in hypersaline environments on the surface of our planet are exposed to the harmful effects of ultraviolet radiation. Therefore, for their protection, they have sunscreen pigments and highly efficient DNA repair and protection systems. The present study aimed to identify new genes involved in UV radiation resistance from these microorganisms, many of which cannot be cultured in the laboratory. Thus, a functional metagenomic approach was used and for this, small-insert libraries were constructed with DNA isolated from microorganisms of high-altitude Andean hypersaline lakes in Argentina (Diamante and Ojo Seco lakes, 4,589 and 3,200 m, respectively) and from the Es Trenc solar saltern in Spain. The libraries were hosted in a UV radiation-sensitive strain of Escherichia coli (recA mutant) and they were exposed to UVB. The resistant colonies were analyzed and as a result, four clones were identified with environmental DNA fragments containing five genes that conferred resistance to UV radiation in E. coli. One gene encoded a RecA-like protein, complementing the mutation in recA that makes the E. coli host strain more sensitive to UV radiation. Two other genes from the same DNA fragment encoded a TATA-box binding protein and an unknown protein, both responsible for UV resistance. Interestingly, two other genes from different and remote environments, the Ojo Seco Andean lake and the Es Trenc saltern, encoded two hypothetical proteins that can be considered homologous based on their significant amino acid similarity (49%). All of these genes also conferred resistance to 4-nitroquinoline 1-oxide (4-NQO), a compound that mimics the effect of UV radiation on DNA, and also to perchlorate, a powerful oxidant that can induce DNA damage. Furthermore, the hypothetical protein from the Es Trenc salterns was localized as discrete foci possibly associated with damaged sites in the DNA in cells treated with 4-NQO, so it could be involved in the repair of damaged DNA. In summary, novel genes involved in resistance to UV radiation, 4-NQO and perchlorate have been identified in this work and two of them encoding hypothetical proteins that could be involved in DNA damage repair activities not previously described.Fil: Lamprecht Grandío, María. Consejo Superior de Investigaciones Cientificas. Centro de Astrobiologia.; EspañaFil: Cortesão, Marta. Consejo Superior de Investigaciones Cientificas. Centro de Astrobiologia.; EspañaFil: Mirete, Salvador. Consejo Superior de Investigaciones Cientificas. Centro de Astrobiologia.; EspañaFil: Benguigui de la Cámara, Macarena. Consejo Superior de Investigaciones Cientificas. Centro de Astrobiologia.; EspañaFil: de Figueras, Carolina G.. Consejo Superior de Investigaciones Cientificas. Centro de Astrobiologia.; EspañaFil: Pérez Pantoja, Danilo. Universidad Tecnológica Metropolitana; EspañaFil: White, Joseph John. Consejo Superior de Investigaciones Cientificas. Centro de Astrobiologia.; EspañaFil: Farias, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Rosselló Móra, Ramon. Instituto Mediterráneo Estudios Avanzados; EspañaFil: González Pastor, José Eduardo. Consejo Superior de Investigaciones Cientificas. Centro de Astrobiologia.; Españ

    Marine Biodiversity in the Caribbean: Regional Estimates and Distribution Patterns

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    This paper provides an analysis of the distribution patterns of marine biodiversity and summarizes the major activities of the Census of Marine Life program in the Caribbean region. The coastal Caribbean region is a large marine ecosystem (LME) characterized by coral reefs, mangroves, and seagrasses, but including other environments, such as sandy beaches and rocky shores. These tropical ecosystems incorporate a high diversity of associated flora and fauna, and the nations that border the Caribbean collectively encompass a major global marine biodiversity hot spot. We analyze the state of knowledge of marine biodiversity based on the geographic distribution of georeferenced species records and regional taxonomic lists. A total of 12,046 marine species are reported in this paper for the Caribbean region. These include representatives from 31 animal phyla, two plant phyla, one group of Chromista, and three groups of Protoctista. Sampling effort has been greatest in shallow, nearshore waters, where there is relatively good coverage of species records; offshore and deep environments have been less studied. Additionally, we found that the currently accepted classification of marine ecoregions of the Caribbean did not apply for the benthic distributions of five relatively well known taxonomic groups. Coastal species richness tends to concentrate along the Antillean arc (Cuba to the southernmost Antilles) and the northern coast of South America (Venezuela – Colombia), while no pattern can be observed in the deep sea with the available data. Several factors make it impossible to determine the extent to which these distribution patterns accurately reflect the true situation for marine biodiversity in general: (1) highly localized concentrations of collecting effort and a lack of collecting in many areas and ecosystems, (2) high variability among collecting methods, (3) limited taxonomic expertise for many groups, and (4) differing levels of activity in the study of different taxa

    Post-intervention Status in Patients With Refractory Myasthenia Gravis Treated With Eculizumab During REGAIN and Its Open-Label Extension

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    OBJECTIVE: To evaluate whether eculizumab helps patients with anti-acetylcholine receptor-positive (AChR+) refractory generalized myasthenia gravis (gMG) achieve the Myasthenia Gravis Foundation of America (MGFA) post-intervention status of minimal manifestations (MM), we assessed patients' status throughout REGAIN (Safety and Efficacy of Eculizumab in AChR+ Refractory Generalized Myasthenia Gravis) and its open-label extension. METHODS: Patients who completed the REGAIN randomized controlled trial and continued into the open-label extension were included in this tertiary endpoint analysis. Patients were assessed for the MGFA post-intervention status of improved, unchanged, worse, MM, and pharmacologic remission at defined time points during REGAIN and through week 130 of the open-label study. RESULTS: A total of 117 patients completed REGAIN and continued into the open-label study (eculizumab/eculizumab: 56; placebo/eculizumab: 61). At week 26 of REGAIN, more eculizumab-treated patients than placebo-treated patients achieved a status of improved (60.7% vs 41.7%) or MM (25.0% vs 13.3%; common OR: 2.3; 95% CI: 1.1-4.5). After 130 weeks of eculizumab treatment, 88.0% of patients achieved improved status and 57.3% of patients achieved MM status. The safety profile of eculizumab was consistent with its known profile and no new safety signals were detected. CONCLUSION: Eculizumab led to rapid and sustained achievement of MM in patients with AChR+ refractory gMG. These findings support the use of eculizumab in this previously difficult-to-treat patient population. CLINICALTRIALSGOV IDENTIFIER: REGAIN, NCT01997229; REGAIN open-label extension, NCT02301624. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that, after 26 weeks of eculizumab treatment, 25.0% of adults with AChR+ refractory gMG achieved MM, compared with 13.3% who received placebo

    Heterologous Expression of the Phytochelatin Synthase CaPCS2 from Chlamydomonas acidophila and Its Effect on Different Stress Factors in Escherichia coli

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    21 Pág. Centro de Investigación Forestal (CIFOR)Phytochelatins (PCs) are cysteine-rich small peptides, enzymatically synthesized from reduced glutathione (GSH) by cytosolic enzyme phytochelatin synthase (PCS). The open reading frame (ORF) of the phytochelatin synthase CaPCS2 gene from the microalgae Chlamydomonas acidophila was heterologously expressed in Escherichia coli strain DH5α, to analyze its role in protection against various abiotic agents that cause cellular stress. The transformed E. coli strain showed increased tolerance to exposure to different heavy metals (HMs) and arsenic (As), as well as to acidic pH and exposure to UVB, salt, or perchlorate. In addition to metal detoxification activity, new functions have also been reported for PCS and PCs. According to the results obtained in this work, the heterologous expression of CaPCS2 in E. coli provides protection against oxidative stress produced by metals and exposure to different ROS-inducing agents. However, the function of this PCS is not related to HM bioaccumulation.This research was funded by grant numbers RTI2018-094867-B-I00, PID2019-104205GB-C22, and PGC2018-096956-B-C42 from the Spanish Ministry of Science and Innovation/ Agency of Research MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”.Peer reviewe

    Políticas de saúde no Brasil nos anos 2000: a agenda federal de prioridades Health policies in Brazil in the 2000s: the national priority agenda

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    O artigo analisa as prioridades da política nacional da saúde no período de 2003 a 2008, correspondente ao Governo Lula. A pesquisa envolveu revisão bibliográfica, análise documental, análise de dados e entrevistas com dirigentes federais. Foram identificadas quatro prioridades na agenda federal da saúde: a Estratégia Saúde da Família, o Brasil Sorridente, os Serviços de Atendimento Móvel de Urgência e o programa Farmácia Popular. A primeira configura uma política de alta densidade institucional, iniciada no governo anterior, constituindo um exemplo de "dependência da trajetória". As demais foram adotadas como marcos de governo e trouxeram inovações em áreas em que havia fragilidades da atuação federal. As quatro políticas prioritárias analisadas se voltam para problemas relevantes do sistema de saúde brasileiro, porém apresentam diferenças quanto à sua trajetória, base de apoio e implicações para os princípios do Sistema Único de Saúde. Apesar de mudanças incrementais, observou-se a predominância de elementos de continuidade na política nacional de saúde no período.<br>This article analyzes Brazilian national health priorities from 2003 to 2008 under the Lula Administration. The study included a literature review, document analysis, and interviews with Federal health administrators. Four priorities were identified on the national health agenda: the Family Health Program, Smiling Brazil, Mobile Emergency Services, and the Popular Pharmacy Program. The first is a policy with high institutional density launched by the previous Administration, constituting an example of path dependence. The other three are innovations in areas where there had been weaknesses in Federal government action. The four policy priorities are strategies focused on solving key problems in the Brazilian health system. However, they display important differences in their historical development, political and institutional base, inclusion on the Federal agenda, and implications for the principles of the Unified National Health System. Although incremental changes have been introduced, national health policy has been characterized predominantly by continuity

    Study of Bc+χcπ+B_c^+ \rightarrow \chi_c \pi^+ decays

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    International audienceA study of Bc+χcπ+B_c^+ \rightarrow \chi_c \pi^+ decays is reported using proton-proton collision data, collected with the LHCb detector at centre-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of 9fb1^{-1}. The decay Bc+χc2π+B_c^+ \rightarrow \chi_{c2} \pi^+ is observed for the first time, with a significance exceeding seven standard deviations. The relative branching fraction with respect to the Bc+J/ψπ+B_c^+ \rightarrow J/\psi \pi^+ decay is measured to be BBc+χc2π+BBc+J/ψπ+=0.37±0.06±0.02±0.01, \frac{\mathcal{B}_{B_c^+ \rightarrow \chi_{c2} \pi^+}} {\mathcal{B}_{B_c^+ \rightarrow J/\psi \pi^+}} = 0.37 \pm 0.06 \pm 0.02 \pm 0.01 , where the first uncertainty is statistical, the second is systematic, and the third is due to the knowledge of the χcJ/ψγ\chi_c \rightarrow J/\psi \gamma branching fraction. No significant Bc+χc1π+B_c^+ \rightarrow \chi_{c1} \pi^+ signal is observed and an upper limit for the relative branching fraction for the Bc+χc1π+B_c^+ \rightarrow \chi_{c1} \pi^+ and Bc+χc2π+B_c^+ \rightarrow \chi_{c2} \pi^+ decays of BBc+χc1π+BBc+χc2π+<0.49 \frac{\mathcal{B}_{B_c^+ \rightarrow \chi_{c1} \pi^+}} {\mathcal{B}_{B_c^+ \rightarrow \chi_{c2} \pi^+}} < 0.49 is set at the 90% confidence level

    A measurement of ΔΓs\Delta \Gamma_{s}

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    Using a dataset corresponding to 9 fb1^{−1} of integrated luminosity collected with the LHCb detector between 2011 and 2018 in proton-proton collisions, the decay-time distributions of the decay modes Bs0J/ψη {B}_s^0\to J/{\psi \eta}^{\prime } and Bs0J/ψπ+π {B}_s^0\to J/\psi {\pi}^{+}{\pi}^{-} are studied. The decay-width difference between the light and heavy mass eigenstates of the Bs0 {B}_s^0 meson is measured to be ∆Γs_{s} = 0.087 ± 0.012 ± 0.009 ps1^{−1}, where the first uncertainty is statistical and the second systematic.[graphic not available: see fulltext]Using a dataset corresponding to 9 fb19~\mathrm{fb}^{-1} of integrated luminosity collected with the LHCb detector between 2011 and 2018 in proton-proton collisions, the decay-time distributions of the decay modes Bs0J/ψηB_s^0 \rightarrow J/\psi \eta' and Bs0J/ψπ+πB_s^0 \rightarrow J/\psi \pi^{+} \pi^{-} are studied. The decay-width difference between the light and heavy mass eigenstates of the Bs0B_s^0 meson is measured to be ΔΓs=0.087±0.012±0.009ps1\Delta \Gamma_s = 0.087 \pm 0.012 \pm 0.009 \, \mathrm{ps}^{-1}, where the first uncertainty is statistical and the second systematic

    Search for D(2007)0μ+μD^{*}(2007)^0\to\mu^+\mu^- in Bπμ+μB^-\to\pi^-\mu^+\mu^- decays

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    International audienceThe very rare D(2007)0μ+μD^{*}(2007)^0\to\mu^+\mu^- decay is searched for by analysing Bπμ+μB^-\to\pi^-\mu^+\mu^- decays. The analysis uses a sample of beauty mesons produced in proton-proton collisions collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 9 fb1^{-1}. The signal signature corresponds to simultaneous peaks in the μ+μ\mu^+\mu^- and πμ+μ\pi^-\mu^+\mu^- invariant masses. No evidence for an excess of events over background is observed and an upper limit is set on the branching fraction of the decay at B(D(2007)0μ+μ)<2.6×108{\cal B}(D^{*}(2007)^0\to\mu^+\mu^-) < 2.6\times 10^{-8} at 90%90\% confidence level. This is the first limit on the branching fraction of D(2007)0μ+μD^{*}(2007)^0\to\mu^+\mu^- decays and the most stringent limit on D(2007)0D^{*}(2007)^0 decays to leptonic final states. The analysis is the first search for a rare charm-meson decay exploiting production via beauty decays
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