1,033 research outputs found

    Gut biogeography of the bacterial microbiota

    Get PDF
    Animals assemble and maintain a diverse but host-specific gut microbial community. In addition to characteristic microbial compositions along the longitudinal axis of the intestines, discrete bacterial communities form in microhabitats, such as the gut lumen, colonic mucus layers and colonic crypts. In this Review, we examine how the spatial distribution of symbiotic bacteria among physical niches in the gut affects the development and maintenance of a resilient microbial ecosystem. We consider novel hypotheses for how nutrient selection, immune activation and other mechanisms control the biogeography of bacteria in the gut, and we discuss the relevance of this spatial heterogeneity to health and disease

    The human commensal Bacteroides fragilis binds intestinal mucin

    Get PDF
    The mammalian gastrointestinal tract harbors a vast microbial ecosystem, known as the microbiota, which benefits host biology. Bacteroides fragilis is an important anaerobic gut commensal of humans that prevents and cures intestinal inflammation. We wished to elucidate aspects of gut colonization employed by B. fragilis. Fluorescence in situ hybridization was performed on colonic tissue sections from B. fragilis and Escherichia coli dual-colonized gnotobiotic mice. Epifluorescence imaging reveals that both E. coli and B. fragilis are found in the lumen of the colon, but only B. fragilis is found in the mucosal layer. This observation suggests that physical association with intestinal mucus could be a possible mechanism of gut colonization by B. fragilis. We investigated this potential interaction using an in vitro mucus binding assay and show here that B. fragilis binds to murine colonic mucus. We further demonstrate that B. fragilis specifically and quantitatively binds to highly purified mucins (the major constituent in intestinal mucus) using flow cytometry analysis of fluorescently labeled purified murine and porcine mucins. These results suggest that interactions between B. fragilis and intestinal mucin may play a critical role during host-bacterial symbiosis

    Banach Analytic Sets and a Non-Linear Version of the Levi Extension Theorem

    Full text link
    We prove a certain non-linear version of the Levi extension theorem for meromorphic functions. This means that the meromorphic function in question is supposed to be extendable along a sequence of complex curves, which are arbitrary, not necessarily straight lines. Moreover, these curves are not supposed to belong to any finite dimensional analytic family. The conclusion of our theorem is that nevertheless the function in question meromorphically extends along an (infinite dimensional) analytic family of complex curves and its domain of existence is a pinched domain filled in by this analytic family.Comment: 19 pages, This is the final version with significant corrections and improvements. To appear in Arkiv f\"or matemati

    Variasi Temperatur Pencampuran Terhadap Parameter Marshall Pada Campuran Lapis Aspal Beton

    Full text link
    This study was conducted to determine the effect of temperature variations on the mixing processof the asphalt concrete AC-WC (Asphalt Concrete-Wearing Course) subtle gradations in themiddle limit and lower limit of the Marshall parameters with reference to specifications of BinaMarga, 2010.From the results of experiments conducted that the optimum asphalt content is used to middle limitusing a asphalt content of 5,7% and 6,8% for the lower limit after that mixing was done usingtemperature variation of 120 o C, 130 o C, 140 o C, 150 o C, and 160 o C.To a mixture of Laston AC-WC subtle gradations middle limit grading 5,7% asphalt contentmixing temperature using a temperature of 120 o C, 130 o C, 140 o C, 150 o C, 160 o C and still meet allstandards of marshall parameters. Ideal mixing temperature variations in the middle limit ofmixing temperature 150 o C-160 o C. While the lower limit to the level of 6,8% asphalt contentmixing temperatures between 120 o C-160 o C did not meet the specifications, because the MQ valuebelow the minimum value of 250 kg / mm

    Accordion Phenomenon in the Radial Artery : Should we treat the radial as a coronary artery?

    Get PDF
    The accordion phenomenon is a well-known finding mechanism in the field of interventional cardiology. It is a benign condition and has mainly been described in tortuous coronary arteries during percutaneous coronary interventions. It is believed to be induced by a stiff guidewire. However, this phenomenon has not been observed previously in the radial artery. We present a case of accordion phenomenon in the radial artery, which was successfully resolved after the catheters and the wire were retrieved, with the pseudolesions found to have completely disappeared in subsequent image findings

    Proinflammatory T-cell responses to gut microbiota promote experimental autoimmune encephalomyelitis

    Get PDF
    Although the effects of commensal bacteria on intestinal immune development seem to be profound, it remains speculative whether the gut microbiota influences extraintestinal biological functions. Multiple sclerosis (MS) is a devastating autoimmune disease leading to progressive deterioration of neurological function. Although the cause of MS is unknown, microorganisms seem to be important for the onset and/or progression of disease. However, it is unclear how microbial colonization, either symbiotic or infectious, affects autoimmunity. Herein, we investigate a role for the microbiota during the induction of experimental autoimmune encephalomyelitis (EAE), an animal model for MS. Mice maintained under germ-free conditions develop significantly attenuated EAE compared with conventionally colonized mice. Germ-free animals, induced for EAE, produce lower levels of the proinflammatory cytokines IFN-γ and IL-17A in both the intestine and spinal cord but display a reciprocal increase in CD4^(+)CD25^(+)Foxp3^+ regulatory T cells (Tregs). Mechanistically, we show that gut dendritic cells from germ-free animals are reduced in the ability to stimulate proinflammatory T cell responses. Intestinal colonization with segmented filamentous bacteria (SFB) is known to promote IL-17 production in the gut; here, we show that SFBs also induced IL-17A–producing CD4^+ T cells (Th17) in the CNS. Remarkably, germ-free animals harboring SFBs alone developed EAE, showing that gut bacteria can affect neurologic inflammation. These findings reveal that the intestinal microbiota profoundly impacts the balance between pro- and antiinflammatory immune responses during EAE and suggest that modulation of gut bacteria may provide therapeutic targets for extraintestinal inflammatory diseases such as MS

    A Pilot Study: Understanding Health Literacy and Linguistic Factors Related to African Immigrants Engagement in Primary Health Care in Massachusetts

    Get PDF
    Culture impacts how individuals understand, communicate, and respond to health information. Immigrants to the U.S. come from diverse cultural groups and have varying understandings of health care and the U.S. health care system. The primary aim of this study is to explore cultural interpretations and beliefs of select health concepts and to assess the health literacy of African immigrants in Massachusetts. We are a partnership between UMass Graduate School of Nursing, Africans for Improved Access program at the Multicultural AIDS Coalition and Clark University. Using a CBPR approach has been valuable in the design of the study and in our ability to access and engage African immigrants. We are recruiting 100 African immigrants during cultural events, targeted outreach and gatherings in religious communities to complete a Freelist exercise, 2 health literacy assessment tools, and a general health survey. Results of the Freelist exercise will inform development of an interview guide that will be used with 3 Focus Groups of African immigrants to help us understand the cultural interpretation of frequently used health related words and phrases. We are assessing the feasibility and acceptability of 2 health literacy instruments to determine the appropriateness of using these assessments with an immigrant population. The association of health literacy to accessing primary care will be examined. The focus group and general health survey data will help us gain a better understanding of the primary care health experiences of African immigrants and potential factors that facilitate or hinder their engagement in primary health care

    Low fatness, reduced fat intake and adequate plasmatic concentrations of LDL-cholesterol are associated with high bone mineral density in women: a cross-sectional study with control group

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Several parameters are associated with high bone mineral density (BMD), such as overweight, black background, intense physical activity (PA), greater calcium intake and some medications. The objectives are to evaluate the prevalence and the main aspects associated with high BMD in healthy women.</p> <p>Methods</p> <p>After reviewing the database of approximately 21,500 BMD scans performed in the metropolitan area of São Paulo, Brazil, from June 2005 to October 2010, high BMD (over 1400 g/cm<sup>2 </sup>at lumbar spine and/or above 1200 g/cm<sup>2 </sup>at femoral neck) was found in 421 exams. Exclusion criteria were age below 30 or above 60 years, black ethnicity, pregnant or obese women, disease and/or medications known to interfere with bone metabolism. A total of 40 women with high BMD were included and matched with 40 healthy women with normal BMD, paired to weight, age, skin color and menopausal status. Medical history, food intake and PA were assessed through validated questionnaires. Body composition was evaluated through a GE-Lunar DPX MD + bone densitometer. Radiography of the thoracic and lumbar spine was carried out to exclude degenerative alterations or fractures. Biochemical parameters included both lipid and hormonal profiles, along with mineral and bone metabolism. Statistical analysis included parametric and nonparametric tests and linear regression models. <it>P </it>< 0.05 was considered significant.</p> <p>Results</p> <p>The mean age was 50.9 (8.3) years. There was no significant difference between groups in relation to PA, smoking, intake of calcium and vitamin D, as well as laboratory tests, except serum C-telopeptide of type I collagen (s-CTX), which was lower in the high BMD group (<it>p </it>= 0.04). In the final model of multivariate regression, a lower fat intake and body fatness as well a better profile of LDL-cholesterol predicted almost 35% of high BMD in women. (adjusted R2 = 0.347; <it>p </it>< 0.001). In addition, greater amounts of lean mass and higher IGF-1 serum concentrations played a protective role, regardless age and weight.</p> <p>Conclusion</p> <p>Our results demonstrate the potential deleterious effect of lipid metabolism-related components, including fat intake and body fatness and worse lipid profile, on bone mass and metabolism in healthy women.</p

    Assessment of metallic element contamination in sediments from the Santos - São Vicente Estuarine System

    Get PDF
    Three approaches were applied to evaluate metal contamination in 41 sediment samples from the Santos - São Vicente Estuarine System: normalization to Al, statistical analysis and sediment quality guidelines (SQGs). The results showed increases in the concentrations of Zn, Ni, Pb, Cd, Cr and Hg, which seemed to be associated with human activities. The levels of Al, Fe and Co probably were associated with crustal material or natural weathering processes. About 45% of the samples presented concentrations exceeding TEL-ERL, levels occasionally associated with adverse biological effects. Four of these samples presented concentrations above PEL-ERM, levels frequently associated with adverse biological effects.FAPES
    corecore