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11.
A bacterial mixed culture able to mineralize molinate was established, through enrichment, using mineral medium with molinate as the only carbon, nitrogen and energy source. The combination of five cultivable isolates, purified from the enrichment culture, permitted the reconstitution of a degrading consortium. Both enrichment and defined cultures were able to mineralize molinate without accumulation of degradation products by the end of the growth. Among the five isolates constituting the defined mixed culture, an actinomycete, strain ON4, was essential for biodegradation, being involved in the cleavage of the thioester bond of molinate, the initial step of the degradation pathway. Isolate ON4 was able to grow on molinate at concentrations below 2 mM, with the accumulation of ethanethiol and diethyl disulphide. These sulphur compounds were toxic to strain ON4 when accumulating at higher concentrations. However, this inhibitory effect was avoided by the presence of other members of the mixed culture, out of which isolates ON1 and ON2 were observed to consume ethanethiol and diethyl disulphide. In this way, interactions among defined mixed culture members involve metabolic and detoxifying association.  相似文献   
12.
The aim of this work was to determine the immunolocalization of the antioxidant enzymes catalase, Cu,Zn-superoxide dismutase (SOD), Mn-SOD, and glutathione peroxidase (GPX) in the bivalve mollusks Mytilus galloprovincialis and Crassostrea sp., the crab Carcinus maenas, and the teleostean fish Mugil cephalus. By immunoblotting, crossreactivity between antibodies and the corresponding proteins in the digestive gland/hepatopancreas of invertebrates and the fish liver was demonstrated. Immunohistochemical studies showed that the stomach epithelium was strongly immunostained for catalase in mollusks. In crabs, ducts showed stronger immunostaining than tubules and in mullet hepatocytes the reaction appeared in discrete granules corresponding to peroxisomes. With regard to Cu,Zn-SOD, the apex of the tubule cells in mussels and crabs was distinctly immunostained, whereas in oysters the reaction was more marked in ducts and in mullet liver a uniform diffuse cytoplasmic staining was found. Mn-SOD was strongly positive in mollusk and crab ducts and in mullet periportal hepatocytes. Finally, GPX was not detected in mussels while in oysters a slight reaction was noted in all cell types. In crabs, connective tissue cells and the apex of duct cells were immunostained, but in mullet liver only erythrocytes appeared reactive. Immunoelectron microscopy revealed that catalase was localized in peroxisomes with a dense labeling in fish and less intense labeling in invertebrates. Cu,Zn-SOD was mainly a cytosolic protein although additional positive subcellular sites (peroxisomes, nuclei) were also observed, while Mn-SOD was restricted to mitochondria. GPX was localized in the cytosol, nucleus, and lysosomes, occurring also in peroxisomes of the fish liver. The results presented here provide a basis for future application of the immunodetection techniques to study the possible differential induction of antioxidant enzymes in aquatic organisms subjected to oxidative stress as a result of exposure to environmental pollutants.  相似文献   
13.
The microtubules of Antarctic fishes, unlike those of homeotherms, assemble at very low temperatures (-1.8 degrees C). The adaptations that enhance assembly of these microtubules are intrinsic to the tubulin dimer and reduce its critical concentration for polymerization at 0 degrees C to approximately 0.9 mg/ml (Williams, R. C., Jr., Correia, J. J., and DeVries, A. L. (1985) Biochemistry 24, 2790-2798). Here we demonstrate that microtubules formed by pure brain tubulins of Antarctic fishes exhibit slow dynamics at both low (5 degrees C) and high (25 degrees C) temperatures; the rates of polymer growth and shortening and the frequencies of interconversion between these states are small relative to those observed for mammalian microtubules (37 degrees C). To investigate the contribution of tubulin primary sequence variation to the functional properties of the microtubules of Antarctic fishes, we have sequenced brain cDNAs that encode 9 alpha-tubulins and 4 beta-tubulins from the yellowbelly rockcod Notothenia coriiceps and 4 alpha-tubulins and 2 beta-tubulins from the ocellated icefish Chionodraco rastrospinosus. The tubulins of these fishes were found to contain small sets of unique or rare residue substitutions that mapped to the lateral, interprotofilament surfaces or to the interiors of the alpha- and beta-polypeptides; longitudinal interaction surfaces are not altered in the fish tubulins. Four changes (A278T and S287T in alpha; S280G and A285S in beta) were present in the S7-H9 interprotofilament "M" loops of some monomers and would be expected to increase the flexibility of these regions. A fifth lateral substitution specific to the alpha-chain (M302L or M302F) may increase the hydrophobicity of the interprotofilament interaction. Two hydrophobic substitutions (alpha:S187A in helix H5 and beta:Y202F in sheet S6) may act to stabilize the monomers in conformations favorable to polymerization. We propose that cold adaptation of microtubule assembly in Antarctic fishes has occurred in part by evolutionary restructuring of the lateral surfaces and the cores of the tubulin monomers.  相似文献   
14.
The structure of tubulin has recently been determined by electron crystallography, paving the way for a clearer understandin of the unique properties of tubulin that allow its varied functions within the cell. Some of the ongoing work on tubulin can be interpreted in terms of its structure, which can serve to guide future studies.  相似文献   
15.
Inflammation is a critical contributor to the pathogenesis of metabolic disorders with adipose tissue being crucial in the inflammatory response by releasing multiple adipokines with either pro- or anti-inflammatory activities with potential functions as metabolic regulators. Peripheral blood mononuclear cells (PBMC) have been proposed as representative of the inflammatory status in obesity. The aim of the present study was to evaluate the contribution of PBMC to the obesity-associated chronic inflammation analyzing the expression of novel adipokines. Samples obtained from 69 subjects were used in the study. Real-time PCR determinations were performed to quantify gene expression levels in PBMC of novel adipokines including chemerin, chitinase-3-like protein 1 (YKL-40), lipocalin-2 (LCN-2) and osteopontin (OPN), and their circulating concentrations were also determined by ELISA. We show, for the first time, that PBMC gene expression levels of chemerin (P < 0.0001), chitinase-3-like protein 1 (P = 0.010), lipocalin-2 (P < 0.0001) and osteopontin (P < 0.0001) were strongly upregulated in obesity independently of the glycemic state. Circulating concentrations of these adipokines followed the same trend being significantly higher (P < 0.05) in obese normoglycemic and type 2 diabetic patients compared to lean volunteers and also associated (P < 0.05) with their corresponding mRNA levels in PBMC. These results provide evidence that alterations in inflammation-related adipokines are manifest in PBMC, which might contribute to the low-grade chronic inflammation that characterizes obesity.

Electronic supplementary material

The online version of this article (doi:10.1007/s12263-015-0460-8) contains supplementary material, which is available to authorized users.  相似文献   
16.

Introduction

As the flows of immigrant populations increase worldwide, their heterogeneity becomes apparent with respect to the differences in the prevalence of chronic physical and mental disease. Multimorbidity provides a new framework in understanding chronic diseases holistically as the consequence of environmental, social, and personal risks that contribute to increased vulnerability to a wide variety of illnesses. There is a lack of studies on multimorbidity among immigrants compared to native-born populations.

Methodology

This nationwide multi-register study in Norway enabled us i) to study the associations between multimorbidity and immigrant origin, accounting for other known risk factors for multimorbidity such as gender, age and socioeconomic levels using logistic regression analyses, and ii) to identify patterns of multimorbidity in Norway for immigrants and Norwegian-born by means of exploratory factor analysis technique.

Results

Multimorbidity rates were lower for immigrants compared to Norwegian-born individuals, with unadjusted odds ratios (OR) and 95% confidence intervals 0.38 (0.37–0.39) for Eastern Europe, 0.58 (0.57–0.59) for Asia, Africa and Latin America, and 0.67 (0.66–0.68) for Western Europe and North America. Results remained significant after adjusting for socioeconomic factors. Similar multimorbidity disease patterns were observed among Norwegian-born and immigrants, in particular between Norwegian-born and those from Western European and North American countries. However, the complexity of patterns that emerged for the other immigrant groups was greater. Despite differences observed in the development of patterns with age, such as ischemic heart disease among immigrant women, we were unable to detect the systematic development of the multimorbidity patterns among immigrants at younger ages.

Conclusions

Our study confirms that migrants have lower multimorbidity levels compared to Norwegian-born. The greater complexity of multimorbidity patterns for some immigrant groups requires further investigation. Health care policies and practice will require a holistic approach for specific population groups in order to meet their health needs and to curb and prevent diseases.  相似文献   
17.
Lipoplexes constituted by calf-thymus DNA (CT-DNA) and mixed cationic liposomes consisting of varying proportions of the cationic lipid 3β-[N-(N',N'-dimethylaminoethane)-carbamoyl]cholesterol hydrochloride (DC-Chol) and the zwitterionic lipid, 1,2-dioleoyl-sn-glycero-3-phosphoetanolamine (DOPE) have been analyzed by means of electrophoretic mobility, SAXS, and fluorescence anisotropy experiments, as well as by theoretically calculated phase diagrams. Both experimental and theoretical studies have been run at several liposome and lipoplex compositions, defined in terms of cationic lipid molar fraction, α, and either the mass or charge ratios of the lipoplex, respectively. The experimental electrochemical results indicate that DC-Chol/DOPE liposomes, with a mean hydrodynamic diameter of around (120 ± 10) nm, compact and condense DNA fragments at their cationic surfaces by means of a strong entropically driven electrostatic interaction. Furthermore, the positive charges of cationic liposomes are compensated by the negative charges of DNA phosphate groups at the isoneutrality L/D ratio, (L/D)(?), which decreases with the cationic lipid content of the mixed liposome, for a given DNA concentration. This inversion of sign process has been also studied by means of the phase diagrams calculated with the theoretical model, which confirms all the experimental results. SAXS diffractograms, run at several lipoplex compositions, reveal that, irrespectively of the lipoplex charge ratio, DC-Chol/DOPE-DNA lipoplexes show a lamellar structure, L(α), when the cationic lipid content on the mixed liposomes α ≥ 0.4, while for a lower content (α = 0.2) the lipoplexes show an inverted hexagonal structure, H(II), usually related with improved cell transfection efficiency. A similar conclusion is reached from fluorescence anisotropy results, which indicate that the fluidity on liposome and lipoplexes membrane, also related with better transfection results, increases as long as the cationic lipid content decreases.  相似文献   
18.
The aim of this study was to establish the anthropometric and physiological profiles of young nonelite soccer players according to their playing position, and to determine their relevance for the selection process. Two hundred forty-one male soccer players who were members of the Getxo Arenas Club (Bizkaia) participated in this study. Players, age 17.31 (+/- 2.64) years, range 14-21 years, were classified into the following groups: forwards (n = 56), midfielders (n = 79), defenders (n = 77), and goalkeepers (n = 29). Anthropometric variables of participants (height, weight, body mass index, 6 skinfolds, 4 diameters, and 3 perimeters) were measured. Also, their somatotype and body composition (weights and percentages of fat, bone, and muscle) were calculated. Participants performed the Astrand test to estimate their absolute and relative VO2max, an endurance test, sprint tests (30 meters flat and 30 meters with 10 cones) and 3 jump tests (squat jump, counter movement jump and drop jump). Forwards were the leanest, presenting the highest percentage of muscle. They were the best performers in all the physiological tests, including endurance, velocity, agility, and power. In contrast, goalkeepers were found to be the tallest and the heaviest players. They also had the largest fat skinfolds and the highest fat percentage, but their aerobic capacity was the lowest. In the selection process, agility and the jump tests were the most discriminating for forwards. In contrast, agility, height, and endurance were the key factors for midfielders. The defenders group was characterized by a lower quantity of fat. Thus, we may conclude that anthropometric and physiological differences exist among soccer players who play in different positions. These differences fit with their different workload in a game. Therefore, training programs should include specific sessions for each positional role.  相似文献   
19.
20.
Gallic acid (3,4,5-trihydroxybenzoic acid, GA) is widely distributed in nature, being a major phenolic pollutant and a commonly used antioxidant and building-block for drug development. We have characterized the first complete cluster (gal genes) responsible for growth in GA in a derivative of the model bacterium Pseudomonas putida KT2440. GalT mediates specific GA uptake and chemotaxis, and highlights the critical role of GA transport in bacterial adaptation to GA consumption. The proposed GA degradation via the central intermediate 4-oxalomesaconic acid (OMA) was revisited and all enzymes involved have been identified. Thus, GalD is the prototype of a new subfamily of isomerases that catalyses a biochemical step that remained unknown, i.e. the tautomerization of the OMAketo generated by the GalA dioxygenase to OMAenol. GalB is the founding member of a new family of zinc-containing hydratases that converts OMAenol into 4-carboxy-4-hydroxy-2-oxoadipic acid (CHA). galC encodes the aldolase catalysing CHA cleavage to pyruvic and oxaloacetic acids. The presence of homologous gal clusters outside the Pseudomonas genus sheds light on the evolution and ecology of the gal genes in GA degraders. The gal genes were used for expanding the metabolic abilities of heterologous hosts towards GA degradation, and for engineering a GA cellular biosensor.  相似文献   
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