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1.
In the United States, there are persistent and widening socioeconomic gaps in morbidity and mortality from chronic diseases. Although most disparities research focuses on person-level socioeconomic-status, mounting evidence suggest that chronic diseases also pattern by the demographic characteristics of neighborhoods. Yet the biological mechanisms underlying these associations are poorly understood. There is increasing recognition that chronic diseases share common pathogenic features, some of which involve alterations in the composition, diversity, and functioning of the gut microbiota. This study examined whether socioeconomic-status was associated with alpha-diversity of the colonic microbiota. Forty-four healthy adults underwent un-prepped sigmoidoscopy, during which mucosal biopsies and fecal samples were collected. Subjects’ zip codes were geocoded, and census data was used to form a composite indicator of neighborhood socioeconomic-status, reflecting household income, educational attainment, employment status, and home value. In unadjusted analyses, neighborhood socioeconomic-status explained 12–18 percent of the variability in alpha-diversity of colonic microbiota. The direction of these associations was positive, meaning that as neighborhood socioeconomic-status increased, so did alpha-diversity of both the colonic sigmoid mucosa and fecal microbiota. The strength of these associations persisted when models were expanded to include covariates reflecting potential demographic (age, gender, race/ethnicity) and lifestyle (adiposity, alcohol use, smoking) confounds. In these models neighborhood socioeconomic-status continued to explain 11–22 percent of the variability in diversity indicators. Further analyses suggested these patterns reflected socioeconomic variations in evenness, but not richness, of microbial communities residing in the sigmoid. We also found indications that residence in neighborhoods of higher socioeconomic-status was associated with a greater abundance of Bacteroides and a lower abundance of Prevotella, suggesting that diet potentially underlies differences in microbiota composition. These findings suggest the presence of socioeconomic variations in colonic microbiota diversity. Future research should explore whether these variations contribute to disparities in chronic disease outcomes.  相似文献   
2.
We propose a methodology for digitally fusing diagnostic decisions made by multiple medical experts in order to improve accuracy of diagnosis. Toward this goal, we report an experimental study involving nine experts, where each one was given more than 8,000 digital microscopic images of individual human red blood cells and asked to identify malaria infected cells. The results of this experiment reveal that even highly trained medical experts are not always self-consistent in their diagnostic decisions and that there exists a fair level of disagreement among experts, even for binary decisions (i.e., infected vs. uninfected). To tackle this general medical diagnosis problem, we propose a probabilistic algorithm to fuse the decisions made by trained medical experts to robustly achieve higher levels of accuracy when compared to individual experts making such decisions. By modelling the decisions of experts as a three component mixture model and solving for the underlying parameters using the Expectation Maximisation algorithm, we demonstrate the efficacy of our approach which significantly improves the overall diagnostic accuracy of malaria infected cells. Additionally, we present a mathematical framework for performing ‘slide-level’ diagnosis by using individual ‘cell-level’ diagnosis data, shedding more light on the statistical rules that should govern the routine practice in examination of e.g., thin blood smear samples. This framework could be generalized for various other tele-pathology needs, and can be used by trained experts within an efficient tele-medicine platform.  相似文献   
3.
BODIPY is an important fluorophores due to its enhanced photophysical and chemical properties including outstanding thermal/photochemical stability, intense absorption/emission profiles, high photoluminescence quantum yield, and small Stokes' shifts. In addition to BODIPY, indole and its derivatives have recently gained attention because of their structural properties and particularly biological importance, therefore these molecules have been widely used in sensing and biosensing applications. Here, we focus on recent studies that reported the incorporation of indole‐based BODIPY molecules as reporter molecules in sensing systems. We highlight the rationale for developing such systems and evaluate detection limits of the developed sensing platforms. Furthermore, we also review the application of indole‐based BODIPY molecules in bioimaging studies. This article includes the evaluation of indole‐based BODIPYs from synthesis to characterization and a comparison of the advantages and disadvantages of developed reporter systems, making it instructive for researchers in various disciplines for the design and development of similar systems.  相似文献   
4.
Diabetes mellitus is a serious worldwide metabolic disease, which is accompanied by hyperglycaemia and affects all organs and body system. Zinc (Zn) is a basic cofactor for many enzymes, which also plays an important role in stabilising the structure of insulin. Liver is the most important target organ after pancreas in diabetic complications. In this study, we aimed to investigate the protective role of Zn in liver damage in streptozotocin (STZ)‐induced diabetes mellitus. There are four experimental groups of female Swiss albino rats: group I: control; group II: control + ZnSO4; group III: STZ‐induced diabetic animals and group IV: STZ‐diabetic + ZnSO4. To induce diabetes, STZ was injected intraperitoneally (65 mg/kg). ZnSO4 (100 mg/kg) was given daily to groups II and IV by gavage for 60 days. At the end of the experiment, rats were killed under anaesthesia and liver tissues were collected. In the diabetic group, hexose, hexosamine, fucose, sialic acid levels, arginase, adenosine deaminase, tissue factor activities and protein carbonyl levels increased, whereas catalase, superoxide dismutase, glutathione‐S‐transferase, glutathione peroxidase, glutathione reductase and Na+/K+‐ATPase activities decreased. The administration of Zn to the diabetic group reversed all the negative effects/activities. According to these results, we can suggest that Zn has a protective role against STZ‐induced diabetic liver damage.  相似文献   
5.
6.
Many types of aflatoxin cause problems for both public and animal health. Aflatoxin B1 (AFB1) is the most toxic and commonly encountered fungal toxin that appears in poultry feed and in feeds stored under unsuitable conditions. AFB1 decreases feed quality, egg production and fertility of hatching eggs. Also, AFB1 alters the development of embryos by infecting eggs. We investigated using sequence analysis the changes caused by different concentrations of AFB1 on the promoter sequences of the growth hormone regulated gene-1 (GHRG-1) in chick embryo at 13, 17, 19 and 21 days incubation. DNA isolated from the liver of chick embryos treated with different concentrations of AFB1 was separated using agarose gel electrophoresis to detect apoptosis, and DNA interaction with AFB1 was investigated using plasmids to detect changes in electrophoretic mobility and their effects on DNA. Base changes of the promoter sequences of GHRG-1 in 5 ng/egg, 15 ng/egg and 40 ng/egg doses of AFB1 were increased on day 19 compared to base changes of the same AFB1 doses on day 13. We also found that AFB at different concentrations changed the mobility of DNA by binding to it, and that high doses of AFB1 destroyed DNA. The DNA interaction study using plasmid demonstrated that AFB1 at high doses was bound to plasmid DNA, slowed its mobility and inhibited restriction cuts.  相似文献   
7.
Abstract

Porcine pancreatic lipase (PPL), Candida rugosa lipase (CRL), and Castor bean lipase (CBL) were immobilized on celite by deposition from aqueous solution by the addition of hexane. Lipolytic performance of free and immobilized lipases were compared and optimizations of lipolytic enzymatic reactions conditions were performed by free and immobilized derivatives using olive oil as substrate. Afterwards, the influence on lipolysis of castor oil of free lipases and immobilized lipase derivatives have been studied in the case of production of ricinoleic acid. All of the lipases performances were compared and enzyme derivative was selected to be very effective on the production of ricinoleic acid by lipolysis reaction. Various reaction parameters affecting the production of ricinoleic acid were investigated with selected the enzyme derivative.

The maximum ricinoleic acid yield was observed at pH 7–8, 50°C, for 3 hours of reaction period with immobilized 1,3-specific PPL on celite. The kinetic constants Km and Vmax were calculated as 1.6 × 10?4 mM and 22.2 mM from a Lineweaver–Burk plot with the same enzyme derivative. To investigate the operational stability of the lipase, the three step lipolysis process was repeated by transferring the immobilized lipase to a substrate mixture. As a result, the percentange of conversion after usage decreased markedly.  相似文献   
8.
Biological Trace Element Research - Total concentrations of heavy metals such as Cu, Fe, Mn, Ni, and Zn in different hazelnut samples obtained by different regions of Sakarya city, Turkey were...  相似文献   
9.
Molecular Biology Reports - Emamectin, a neurotoxic agent, is a semi-synthetic insecticide that belongs to the Avermectin family and is used against helmintic infections in the Salmonidae family....  相似文献   
10.
This study was carried out to better understand the role of salicylic acid (SA) applied before cold stress in the cold tolerance mechanism. Two barley (Hordeum vulgare) cultivars, cold-sensitive (Akhisar) and cold-tolerant (Tokak), were used and 0.1 mM SA was applied to 7-d-old barley seedlings growing under control conditions (20/18 °C). The seedlings were transferred to cold chamber (7/5 °C) at the age 14, 21, and 28 d. After three days, the leaves were harvested to determine the activities of apoplastic antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POX) and ice nucleation activity and electrophoretic patterns of apoplastic proteins. Cold treatment decreased the activities of all enzymes in cold-sensitive cultivar, however, it increased CAT and POX activities in cold-tolerant cultivar. Exogenous SA increased enzyme activities in both cultivars. Ice nucleation activity increased by cold treatment, especially in 17-d-old seedlings in both cultivars. In addition, SA treatment increased ice nucleation activity in all examined samplings in both cultivars. SA treatment caused accumulation or de novo synthesis of some apoplastic proteins. The results of the present study show that exogenous SA can improve cold tolerance by regulating the activities of apoplastic antioxidative enzymes, ice nucleation activity, and the patterns of apoplastic proteins.  相似文献   
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