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41.
S. Civelek R. Gelişgen G. Andican A. Seven S. H. Küçük M. Özdoğan G. Burçak 《Biometals》2010,23(1):43-49
The effects of Cu(II) supplementation on glycemic parameters, advanced glycation end products (AGEs), antioxidant status (glutathione;
GSH and total antioxidant capacity; TAOC) and lipid peroxidative damage (thiobarbituric acid-reactive substances, TBARS) were
investigated in streptozotocin (STZ) induced diabetic rats. The study was carried out on Wistar albino rats grouped as control
(n = 10), CuCl2 treated (n = 9), STZ (n = 10) and STZ,CuCl2 treated (n = 9). STZ was administered intraperitoneally at a single dose of 65 mg/kg and CuCl2, 4 mg copper/kg, subcutaneously, every 2 days for 60 days. At the end of this period, glucose(mg/dl), Cu(μg/dl), TBARS(μmol/l),
TAOC(mmol/l) were measured in plasma, GSH(mg/gHb) in erythrocytes and glycated hemoglobin (GHb)(%) in blood. Plasma AGE-peptides(%)
were measured by HPLC flow system with spectrofluorimetric and spectrophotometric detectors connected on-line. Data were analyzed
by the non-parametric Kruskal–Wallis and Mann–Whitney U test. In the STZ group glucose, GHb and AGE-peptide levels were all
significantly higher than the control group (P < 0.01, P < 0.05, and P < 0.01, respectively). CuCl2 treated group had significantly lower glucose but significantly higher GHb, TAOC and TBARS levels than the control group
(P < 0.05, P < 0.001, P < 0.05 and P < 0.001, respectively). STZ,CuCl2 treated group had significantly higher GHb, TAOC and TBARS levels compared with the control group (P < 0.001, P < 0.05 and P < 0.05, respectively); but only TAOC level was significantly higher than the STZ group (P < 0.01). This experimental study provides evidence that copper intake increases total antioxidant capacity in both nondiabetic
and diabetic states. However despite the potentiated antioxidant defence, lipid peroxidation and glycation enhancing effects
of CuCl2 are evident under nondiabetic conditions. 相似文献
42.
43.
Mercè Padró José A. Castillo Livia Gómez Jesús Joglar Pere Clapés Carme de Bolós 《Glycoconjugate journal》2010,27(2):277-285
Iminosugars are monosaccharide analogues that have been demonstrated to be specific inhibitors for glycosidases and are currently used therapeutically in several human disorders. N-alkylated derivatives of d-fagomine and (2R,3S,4R,5S)-2-(hydroxymethyl)-5-methylpyrrolidine-3,4-diol with aliphatic chains were tested in eight human cancer cell lines to analyze their cytotoxicity and the inhibitory effect in the activities of specific glycosidases. Results indicate that these compounds were more cytotoxic as the length of the alkyl chain increases. N-dodecyl-d-fagomine inhibited specifically the α-d-glucosidase activity in cell lysates, whereas no effect was detected in other glycosidases. The N-dodecyl derivative of (2R,3S,4R,5S)-2-(Hydroxymethyl)-5-methylpyrrolidine-3,4-diol induced specific inhibition against α-l-fucosidase in cell lysates. Our results indicated that the length of the alkyl chain linked to the iminosugars determine their cytotoxicity as well as the inhibitory effect on the enzymatic activities of specific glycosidases, in human cancer cell lines. 相似文献
44.
Maria Giné-Garriga Carme Martin-Borràs Anna Puig-Ribera Carlos Martín-Cantera Mercè Solà Antonio Cuesta-Vargas 《PloS one》2013,8(6)
Background
Effective promotion of exercise could result in substantial savings in healthcare cost expenses in terms of direct medical costs, such as the number of medical appointments. However, this is hampered by our limited knowledge of how to achieve sustained increases in physical activity.Objectives
To assess the effectiveness of a Primary Health Care (PHC) based physical activity program in reducing the total number of visits to the healthcare center among inactive patients, over a 15-month period.Research Design
Randomized controlled trial.Subjects
Three hundred and sixty-two (n = 362) inactive patients suffering from at least one chronic condition were included. One hundred and eighty-three patients (n = 183; mean (SD); 68.3 (8.8) years; 118 women) were randomly allocated to the physical activity program (IG). One hundred and seventy-nine patients (n = 179; 67.2 (9.1) years; 106 women) were allocated to the control group (CG). The IG went through a three-month standardized physical activity program led by physical activity specialists and linked to community resources.Measures
The total number of medical appointments to the PHC, during twelve months before and after the program, was registered. Self-reported health status (SF-12 version 2) was assessed at baseline (month 0), at the end of the intervention (month 3), and at 12 months follow-up after the end of the intervention (month 15).Results
The IG had a significantly reduced number of visits during the 12 months after the intervention: 14.8 (8.5). The CG remained about the same: 18.2 (11.1) (P = .002).Conclusions
Our findings indicate that a 3-month physical activity program linked to community resources is a short-duration, effective and sustainable intervention in inactive patients to decrease rates of PHC visits.Trial Registration
ClinicalTrials.gov NCT00714831相似文献45.
BCL-XL regulates TNF-alpha-mediated cell death independently of NF-kappaB, FLIP and IAPs 总被引:1,自引:0,他引:1
46.
John R. Collette Richard J. Chi Douglas R. Boettner Isabel M. Fernandez-Golbano Rachael Plemel Alex J. Merz Maria Isabel Geli Linton M. Traub Sandra K. Lemmon 《Molecular biology of the cell》2009,20(14):3401-3413
Clathrin is involved in vesicle formation in the trans-Golgi network (TGN)/endosomal system and during endocytosis. Clathrin recruitment to membranes is mediated by the clathrin heavy chain (HC) N-terminal domain (TD), which forms a seven-bladed β-propeller. TD binds membrane-associated adaptors, which have short peptide motifs, either the clathrin-box (CBM) and/or the W-box; however, the importance of the TD binding sites for these motifs has not been tested in vivo. We investigated the importance of the TD in clathrin function by generating 1) mutations in the yeast HC gene (CHC1) to disrupt the binding sites for the CBM and W-box (chc1-box), and 2) four TD-specific temperature-sensitive alleles of CHC1. We found that TD is important for the retention of resident TGN enzymes and endocytosis of α-factor; however, the known adaptor binding sites are not necessary, because chc1-box caused little to no effect on trafficking pathways involving clathrin. The Chc1-box TD was able to interact with the endocytic adaptor Ent2 in a CBM-dependent manner, and HCs encoded by chc1-box formed clathrin-coated vesicles. These data suggest that additional or alternative binding sites exist on the TD propeller to help facilitate the recruitment of clathrin to sites of vesicle formation. 相似文献
47.
48.
Giblin J Fernández-Golbano IM Idrissi FZ Geli MI 《Biochemical Society transactions》2011,39(5):1185-1190
Myosins-I are widely expressed actin-dependent motors which bear a phospholipid-binding domain. In addition, some members of the family can trigger Arp2/3 complex (actin-related protein 2/3 complex)-dependent actin polymerization. In the early 1990s, the development of powerful genetic tools in protozoa and mammals and discovery of these motors in yeast allowed the demonstration of their roles in membrane traffic along the endocytic and secretory pathways, in vacuole contraction, in cell motility and in mechanosensing. The powerful yeast genetics has contributed towards dissecting in detail the function and regulation of Saccharomyces cerevisiae myosins-I Myo3 and Myo5 in endocytic budding from the plasma membrane. In the present review, we summarize the evidence, dissecting their exact role in membrane budding and the molecular mechanisms controlling their recruitment and biochemical activities at the endocytic sites. 相似文献
49.
Eric Elguero Céline Arnathau Patrick Durand Sylvain Brisse Laure Diancourt Agnes Aubouy Pierre Becquart Umberto D'Alessandro Didier Fontenille Dionicia Gamboa Amanda Maestre Didier Ménard Lise Musset Oscar Noya Vincent Veron Albina Wide Bernard Carme Eric Legrand Christine Chevillon Francisco J. Ayala Franck Prugnolle 《Molecular ecology》2014,23(8):1979-1993
Pathogens, which have recently colonized a new host species or new populations of the same host, are interesting models for understanding how populations may evolve in response to novel environments. During its colonization of South America from Africa, Plasmodium falciparum, the main agent of malaria, has been exposed to new conditions in distinctive new human populations (Amerindian and populations of mixed origins) that likely exerted new selective pressures on the parasite's genome. Among the genes that might have experienced strong selective pressures in response to these environmental changes, the eba genes (erythrocyte‐binding antigens genes), which are involved in the invasion of the human red blood cells, constitute good candidates. In this study, we analysed, in South America, the polymorphism of three eba genes (eba‐140, eba‐175, eba‐181) and compared it to the polymorphism observed in African populations. The aim was to determine whether these genes faced selective pressures in South America distinct from what they experienced in Africa. Patterns of genetic variability of these genes were compared to the patterns observed at two housekeeping genes (adsl and serca) and 272 SNPs to separate adaptive effects from demographic effects. We show that, conversely to Africa, eba‐140 seemed to be under stronger diversifying selection in South America than eba‐175. In contrast, eba‐181 did not show any sign of departure from neutrality. These changes in the patterns of selection on the eba genes could be the consequence of changes in the host immune response, the host receptor polymorphisms and/or the ability of the parasite to silence or express differentially its invasion proteins. 相似文献
50.
Carme Suárez-Germà Jordi Hernández-Borrell Manuel Prieto 《Molecular membrane biology》2014,31(4):120-130
Förster resonance energy transfer (FRET) is a photophysical process by which a donor (D) molecule in an electronic excited state transfers its excitation energy to a second species, the acceptor (A). Since FRET efficiency depends on D-A separation, the measurement of donor fluorescence in presence and absence of the acceptor allows determination of this distance, and therefore FRET has been extensively used as a “spectroscopic ruler”. In membranes, interpretation of FRET is more complex, since one D may be surrounded by many A molecules. Such is the case encountered with membrane proteins and lipids in the bilayer. This paper reviews the application of a model built to analyze FRET data between a single tryptophan mutant of the transmembrane protein lactose permease (W151/C154G of LacY), the sugar/H+ symporter from Escherichia coli, and different pyrene-labeled phospholipids. Several variables of the system with biological implication have been investigated: The selectivity of LacY for different species of phospholipids, the enhancement of the sensitivity of the FRET modeling, and the mutation of a particular aminoacid (D68C) of the protein. The results obtained support: (i) Preference of LacY for phosphatidylethanolamine (PE) over phosphatidylglycerol (PG); (ii) affinity of LacY for fluid (Lα) phases; and (iii) importance of the aspartic acid in position 68 in the sequence of LacY regarding the interaction with the phospholipid environment. Besides, by exploring the enhancement of the sensitivity by using pure lipid matrices with higher mole fractions of labelled-phospholipid, the dependence on acyl chain composition is unveiled. 相似文献