The impact of high non-starch polysaccharide intake on serum micronutrient concentrations in a cohort of women

OBJECTIVE: Many public health campaigns encourage increased fibre consumption, but short-term studies suggest that various components of dietary fibre inhibit the absorption of certain micronutrients including carotenoids. These do not take into account long-term adaptation to nutrient intake levels. We aimed to investigate the effect of non-starch polysaccharide (NSP) fibre on plasma micronutrient concentrations in a large free-living population consuming their usual diet. DESIGN: Prospective cohort study. Semi-weighed 4-day food diaries were analysed for micronutrient and NSP fibre intakes. Blood samples were taken and analysed for carotenoids, vitamin A, vitamin E, thiamine, riboflavin, vitamin B6, vitamin B12, folic acid, vitamin C and trace metals. SETTING: Participants in a large national cohort study who lived within 30 miles of Leeds. SUBJECTS: Two hundred and eighty-three middle-aged women. RESULTS: The association between NSP intake and plasma nutrient concentrations was assessed taking into account nutrient intakes and other dietary and lifestyle factors. Higher levels of NSP were not associated with lower plasma concentrations of the micronutrients measured, even allowing for the higher nutrient levels generally found in high-fibre foods. CONCLUSIONS: Amongst middle-aged women we have shown that current guidelines for increasing the population's NSP consumption can be safely applied. Such guidelines are unlikely to reduce serum micronutrient concentrations, although other, more vulnerable population groups may benefit from further investigation.     

“In”-sights about food banks from a critical interpretive synthesis of the academic literature

The persistence, and international expansion, of food banks as a non-governmental response to households experiencing food insecurity has been decried as an indicator of unacceptable levels of poverty in the countries in which they operate. In 1998, Poppendieck published a book, Sweet charity: emergency food and the end of entitlement, which has endured as an influential critique of food banks. Sweet charity‘s food bank critique is succinctly synthesized as encompassing seven deadly “ins” (1) inaccessibility, (2) inadequacy, (3) inappropriateness, (4) indignity, (5) inefficiency, (6) insufficiency, and (7) instability. The purpose of this paper is to examine if and how the contemporary food bank critique differs from Sweet charity’s “ins” as a strategy for the formulation of synthesizing arguments for policy advocacy. We used critical interpretive synthesis methodology to identify relationships within and/or between existing critiques in the peer-reviewed literature as a means to create “‘synthetic constructs’ (new constructs generated through synthesis)” of circulating critiques. We analyzed 33 articles on food banks published since Sweet charity, with the “ins” as a starting point for coding. We found that the list of original “ins” related primarily to food bank operations has been consolidated over time. We found additional “ins” that extend the food bank critique beyond operations (ineffectiveness, inequality, institutionalization, invalidation of entitlements, invisibility). No synthetic construct emerged linking the critique of operational challenges facing food banks with one that suggests that food banks may be perpetuating inequity, posing a challenge for mutually supportive policy advocacy.     

HTLV-III/LAV-neutralizing antibodies to an E. coli-produced fragment of the virus envelope

Immunization with either an Escherichia coli recombinant segment of the human T-cell lymphotropic virus (HTLV-III/LAV) envelope protein (gp 120) or with deglycosylated gp 120 envelope protein produced antibodies that neutralize HTLV-III/LAV infection in vitro. Virus neutralization titers of these antisera were equivalent to those obtained with purified native gp120 as immunogen. This localizes at least one class of neutralizing epitopes to the carboxyl-terminal half of the molecule. In addition, native gp120 prevented HTLV-III/LAV--mediated cell fusion, whereas the recombinant gp120 fragment did not. This shows that although glycosylation is not required for induction of neutralizing antibodies, it may be important for interaction with CD4, the virus receptor. A segment of the HTLV-III/LAV envelope produced in E. coli may be an important ingredient of a vaccine for acquired immune deficiency syndrome.     

A genomic view of the human-Bacteroides thetaiotaomicron symbiosis

The human gut is colonized with a vast community of indigenous microorganisms that help shape our biology. Here, we present the complete genome sequence of the Gram-negative anaerobe Bacteroides thetaiotaomicron, a dominant member of our normal distal intestinal microbiota. Its 4779-member proteome includes an elaborate apparatus for acquiring and hydrolyzing otherwise indigestible dietary polysaccharides and an associated environment-sensing system consisting of a large repertoire of extracytoplasmic function sigma factors and one- and two-component signal transduction systems. These and other expanded paralogous groups shed light on the molecular mechanisms underlying symbiotic host-bacterial relationships in our intestine.     

热激因子基因AtHSFa1a提高烟草的耐热性研究

克隆了拟南芥热激因子AtHSFa1a,并由热激启动子AtHSP70b控制,构建了双元表达载体pV-70bAtHSFa1a,并经农杆菌介导转化烟草,获得了转基因植株,并检测了其耐热性指标.结果显示:与对照相比,转基因烟草的电导率较低,丙二醛含量增幅较小,SOD酶活性较高,初步表明其对高温具有更高的耐受性.     

Detection of widespread fluids in the Tibetan crust by magnetotelluric studies

Magnetotelluric exploration has shown that the middle and lower crust is anomalously conductive across most of the north-to-south width of the Tibetan plateau. The integrated conductivity (conductance) of the Tibetan crust ranges from 3000 to greater than 20,000 siemens. In contrast, stable continental regions typically exhibit conductances from 20 to 1000 siemens, averaging 100 siemens. Such pervasively high conductance suggests that partial melt and/or aqueous fluids are widespread within the Tibetan crust. In southern Tibet, the high-conductivity layer is at a depth of 15 to 20 kilometers and is probably due to partial melt and aqueous fluids in the crust. In northern Tibet, the conductive layer is at 30 to 40 kilometers and is due to partial melting. Zones of fluid may represent weaker areas that could accommodate deformation and lower crustal flow.     

Short-term mortality predictions for critically ill hospitalized adults: science and ethics

Modern life-sustaining therapy often succeeds in postponing death but may be ineffective at restoring health. Decisions that influence the time and circumstances of an individual's death are now common and require an accurate and comprehensive characterization of likely outcome. Evaluation of alternative outcomes requires acknowledgement that most patients find some outcomes to be worse than death. Improved understanding of major predictors of patient outcome, combined with rapidly expanding technical abilities to collect and manipulate large amounts of detailed clinical data, have created a new intellectual and technical basis for estimating outcomes from intensive medical care. Such objective probability estimates, such as the system described here, can reduce uncertainty about difficult clinical decisions and can be used by physicians, patients, and society to reorient health care toward more scientifically and ethically defensible approaches.