577 research outputs found

    Gastric microbial community profiling reveals a dysbiotic cancer-associated microbiota

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    Objective Gastric carcinoma development is triggered by Helicobacter pylori. Chronic H. pylori infection leads to reduced acid secretion, which may allow the growth of a different gastric bacterial community. This change in the microbiome may increase aggression to the gastric mucosa and contribute to malignancy. Our aim was to evaluate the composition of the gastric microbiota in chronic gastritis and in gastric carcinoma. Design The gastric microbiota was retrospectively investigated in 54 patients with gastric carcinoma and 81 patients with chronic gastritis by 16S rRNA gene profiling, using next-generation sequencing. Differences in microbial composition of the two patient groups were assessed using linear discriminant analysis effect size. Associations between the most relevant taxa and clinical diagnosis were validated by real-time quantitative PCR. Predictive functional profiling of microbial communities was obtained with PICRUSt. Results The gastric carcinoma microbiota was characterised by reduced microbial diversity, by decreased abundance of Helicobacter and by the enrichment of other bacterial genera, mostly represented by intestinal commensals. The combination of these taxa into a microbial dysbiosis index revealed that dysbiosis has excellent capacity to discriminate between gastritis and gastric carcinoma. Analysis of the functional features of the microbiota was compatible with the presence of a nitrosating microbial community in carcinoma. The major observations were confirmed in validation cohorts from different geographic origins. Conclusions Detailed analysis of the gastric microbiota revealed for the first time that patients with gastric carcinoma exhibit a dysbiotic microbial community with genotoxic potential, which is distinct from that of patients with chronic gastritis.This research was supported by a Worldwide Cancer Research grant to CF and JCM (Reference 16-1352). RMF, JPM and IPR have fellowships from Fundacao para a Ciencia e a Tecnologia (FCT; SFRH/BPD/84084/2012, PD/BD/114014/2015 and SFRH/BD/110803/2015, respectively) through Programa Operacional Capital Humano (POCH) and the European Union. JPM's fellowship is in the framework of FCT's PhD Programme BiotechHealth (Ref PD/0016/2012). i3S-Instituto de Investigacao e Inovacao em Saude is funded by Fundo Europeu de Desenvolvimento Regional (FEDER) funds through the COMPETE 2020-Operacional Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, and by Portuguese funds through Fundacao para a Ciencia e a Tecnologia (FCT)/Ministerio da Ciencia, Tecnologia e Inovacao (POCI-01-0145-FEDER-007274)

    Validation of a fluorescence in situ hybridization method using peptide nucleic acid probes for detection of helicobacter pylori clarithromycin resistance in gastric biopsy specimens

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    Here, we evaluated a previously established peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH) method as a new diagnostic test for Helicobacter pylori clarithromycin resistance detection in paraffin-embedded gastric biopsy specimens. Both a retrospective study and a prospective cohort study were conducted to evaluate the specificity and sensitivity of a PNA-FISH method to determine H. pylori clarithromycin resistance. In the retrospective study (n 30 patients), full agreement between PNA-FISH and PCR-sequencing was observed. Compared to the reference method (culture followed by Etest), the specificity and sensitivity of PNA-FISH were 90.9% (95% confidence interval [CI], 57.1% to 99.5%) and 84.2% (95% CI, 59.5% to 95.8%), respectively. In the prospective cohort (n 93 patients), 21 cases were positive by culture. For the patients harboring clarithromycin- resistant H. pylori, the method showed sensitivity of 80.0% (95% CI, 29.9% to 98.9%) and specificity of 93.8% (95% CI, 67.7% to 99.7%). These values likely represent underestimations, as some of the discrepant results corresponded to patients infected by more than one strain. PNA-FISH appears to be a simple, quick, and accurate method for detecting H. pylori clarithromycin resistance in paraffin-embedded biopsy specimens. It is also the only one of the methods assessed here that allows direct and specific visualization of this microorganism within the biopsy specimens, a characteristic that allowed the observation that cells of different H. pylori strains can subsist in very close proximity in the stomach

    Intravitreal ranibizumab for myopic choroidal neovascularization: 12-month results

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    PURPOSE: The purpose of this study was to evaluate the safety and efficacy of intravitreal ranibizumab after 12 months in the treatment of choroidal neovascularization secondary to pathologic myopia. METHODS: This was a prospective, multicenter, consecutive, nonrandomized, interventional case series. The study included 34 eyes of 32 patients with choroidal neovascularization secondary to pathologic myopia; 13 eyes had previous photodynamic therapy, and 21 eyes had no previous treatment. The patients were followed for > or = 12 months. Best-corrected visual acuity, optical coherence tomography, and the presence of metamorphopsia were assessed monthly. RESULTS: Mean visual acuity improved 8 letters from baseline to 12-month follow-up, and the difference was statistically significant (P or = 3 lines, 44% improved > or = 2 lines, 65% improved > or = 1 line, and 79% improved > or = 0 lines. Central retinal thickness decreased significantly from baseline to the 12-month follow-up (P < 0.01). A mean of 3.6 treatments were performed during the 12-month follow-up, and no systemic or ocular side effects were registered during that time. CONCLUSION: One-year results of intravitreal ranibizumab for myopic choroidal neovascularization are very promising. Additional prospective studies are necessary to better determine long-term efficacy and safety

    Analysis of the Cochrane Review: Exercise-Based Cardiac Rehabilitation for Coronary Heart Disease. Cochrane Database Syst Rev. 2016;1:CD001800

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    A doença coronária, responsável por um terço de todas as mortes, é a causa de morte mais comum em todo o mundo. Todavia, com o decréscimo das taxas de mortalidade associadas a esta patologia, observa-se um número crescente de doentes com a doença, com aumento da necessidade de gestão dos seus sintomas e prognóstico. A reabilitação cardíaca, componente essencial do tratamento contemporâneo da doença arterial coronária, é uma intervenção complexa que envolve variadas técnicas, incluindo exercício físico, correção dos fatores de risco cardiovasculares tradicionais, terapia comportamental e apoio psicológico, sendo considerada uma prioridade em países em que a prevalência da doença é elevada. Esta revisão sistemática Cochrane constitui uma atualização de uma revisão Cochrane publicada em 2011, tendo identificado 16 novos ensaios clínicos (3872 doentes), predominantemente em status pós-enfarte agudo do miocárdio e pós-cirurgia de revascularização miocárdica. Incluiu, assim, 63 ensaios clínicos aleatorizados que estudaram a eficácia e o custo-efetividade da reabilitação cardíaca baseada no exercício físico, em pacientes com doença arterial coronária. A confiança na evidência científica variou de baixa a moderada. Dos principais resultados destaca-se o efeito da reabilitação cardíaca, em comparação com a ausência de exercício físico, na redução na mortalidade cardiovascular, todavia sem redução da mortalidade total. Apesar da reabilitação cardíaca ter diminuído o risco global de internamento hospitalar, o mesmo não se verificou para o risco de enfarte, cirurgia de revascularização miocárdica ou intervenção coronária percutânea. Neste artigo sumarizam-se e discutem-se os principais resultados, conclusões e implicações desta revisão sistemática para a prática clínica.info:eu-repo/semantics/publishedVersio

    Kerr-CFT From Black-Hole Thermodynamics

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    We analyze the near-horizon limit of a general black hole with two commuting killing vector fields in the limit of zero temperature. We use black hole thermodynamics methods to relate asymptotic charges of the complete spacetime to those obtained in the near-horizon limit. We then show that some diffeomorphisms do alter asymptotic charges of the full spacetime, even though they are defined in the near horizon limit and, therefore, count black hole states. We show that these conditions are essentially the same as considered in the Kerr/CFT corresponcence. From the algebra constructed from these diffeomorphisms, one can extract its central charge and then obtain the black hole entropy by use of Cardy's formula.Comment: 19 pages, JHEP3, no figures. V2: References added, small typos fixe

    The holographic principle

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    There is strong evidence that the area of any surface limits the information content of adjacent spacetime regions, at 10^(69) bits per square meter. We review the developments that have led to the recognition of this entropy bound, placing special emphasis on the quantum properties of black holes. The construction of light-sheets, which associate relevant spacetime regions to any given surface, is discussed in detail. We explain how the bound is tested and demonstrate its validity in a wide range of examples. A universal relation between geometry and information is thus uncovered. It has yet to be explained. The holographic principle asserts that its origin must lie in the number of fundamental degrees of freedom involved in a unified description of spacetime and matter. It must be manifest in an underlying quantum theory of gravity. We survey some successes and challenges in implementing the holographic principle.Comment: 52 pages, 10 figures, invited review for Rev. Mod. Phys; v2: reference adde

    Helicobacter pylori chronic infection and mucosal inflammation switches the human gastric glycosylation pathways

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    Helicobacter pylori exploits host glycoconjugates to colonize the gastric niche. Infection can persist for decades promoting chronic inflammation, and in a subset of individuals lesions can silently progress to cancer. This study shows that H. pylori chronic infection and gastric tissue inflammation result in a remodeling of the gastric glycophenotype with increased expression of sialyl-Lewis a/x antigens due to transcriptional up-regulation of the B3GNT5, B3GALT5, and FUT3 genes. We observed that H. pylori infected individuals present a marked gastric local pro-inflammatory signature with significantly higher TNF-a levels and demonstrated that TNF-induced activation of the NF-kappaB pathway results in B3GNT5 transcriptional up-regulation. Furthermore, we show that this gastric glycosylation shift, characterized by increased sialylation patterns, favors SabA-mediated H. pylori attachment to human inflamed gastric mucosa. This study provides novel clinically relevant insights into the regulatory mechanisms underlying H. pylori modulation of host glycosylation machinery, and phenotypic alterations crucial for life-long infection. Moreover, the biosynthetic pathways here identified as responsible for gastric mucosa increased sialylation, in response to H. pylori infection, can be exploited as drug targets for hindering bacteria adhesion and counteract the infection chronicity.IPATIMUP integrates the i3S Research Unit, which is partially supported by FCT, the Portuguese Foundation for Science and Technology (PEst C/SAU/LA0003/2013). This work is funded by FEDER funds through the Operational Programme for Competitiveness Factors-COMPETE (NORTE 07 0124 FEDER 000024; FCOMP-01-0124-FEDER028188; FCOMP-01-0124-FEDER 041276) and National Funds through the FCT-Foundation for Science and Technology (EXPL/CTM-BIO/0762/2013, PTDC/BBB-EBI/0786/2012) and acknowledges support by the EuropeanUnion (Seventh Framework Programme GastricGlycoExplorer project, grant number 316929). Grants were received from FCT, POPH (Programa Operacional Potencial Humano) and FSE (Fundo Social Europeu) (SFRH/BPD/75871/2011 to AM;SFRH/SINTD/60034/2009 to RMP; SFRH/BPD/84084/2012 to RMF; SFRH/BPD/89764/2012 to PO). AM acknowledges EMBO for a Short-Term Fellowship (EMBO ASTF 330-212). Transcript analysis was funded by NIH (grant P41GM103490) to KWM

    Health and Sickness Absence in Denmark: A Study of Elderly-Care Immigrant Workers

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    The objective of this study is to investigate patterns of sickness absence in light of health status among immigrants. Cross-sectional data from 2005 was used and the study population consisted of 3,121 healthcare assistants and healthcare helpers working in the elderly-care sector in Denmark. A multinomial logistic regression was employed to investigate the relationship between health indicator, sickness absence and being an immigrant. Our findings show that, on one hand, immigrants have worse health status, but on the other, they have significantly lower sickness absence than their Danish counterparts, even after factors such as age and gender are controlled for. The results show that the relationship between being an immigrant and sickness absence differs according to health status. Our findings are in line with Steer and Rhode’s theoretical framework, according to which attendance to work is a function of ability and motivation to be at work

    The age patterns of severe malaria syndromes in sub-Saharan Africa across a range of transmission intensities and seasonality settings

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    BACKGROUND: A greater understanding of the relationship between transmission intensity, seasonality and the age-pattern of malaria is needed to guide appropriate targeting of malaria interventions in different epidemiological settings. METHODS: A systematic literature review identified studies which reported the age of paediatric hospital admissions with cerebral malaria (CM), severe malarial anaemia (SMA), or respiratory distress (RD). Study sites were categorized into a 3 × 2 matrix of Plasmodium falciparum transmission intensity and seasonality. Probability distributions were fitted by maximum likelihood methods, and best fitting models were used to estimate median ages and to represent graphically the age-pattern of each outcome for each transmission category in the matrix. RESULTS: A shift in the burden of CM towards younger age groups was seen with increasing intensity of transmission, but this was not the case for SMA or RD. Sites with 'no marked seasonality' showed more evidence of skewed age-patterns compared to areas of 'marked seasonality' for all three severe malaria syndromes. CONCLUSIONS: Although the peak age of CM will increase as transmission intensity decreases in Africa, more than 75% of all paediatric hospital admissions of severe malaria are likely to remain in under five year olds in most epidemiological settings
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