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111.
Fahimeh Ramezani Tehrani Seyed Ali Montazeri Farhad Hosseinpanah Leila Cheraghi Hadi Erfani Maryam Tohidi Fereidoun Azizi 《PloS one》2015,10(9)
Objective
To see the changes of cardio-metabolic risk factors overtime in polycystic ovary syndrome vs. control women.Methods
This study was conducted on 637 participants (85 PCOS and 552 control reproductive aged, 18–45 years) of Tehran Lipid and Glucose Study (TLGS), an ongoing population-based cohort study with 12 years of follow-up. The cardiovascular risk factors of these groups were assessed in three-year intervals using standard questionnaires, history taking, anthropometric measures, and metabolic/endocrine evaluation. Generalized estimating equation was used to analyze the data.Results
Overall mean of insulin (3.55, CI: 0.66–6.45), HOMA-IR (0.63, CI: 0.08–1.18), and HOMA-β (45.90, CI: 0.86–90.93) were significantly higher in PCOS than in healthy women after adjustment for age, BMI, and baseline levels. However, the negative interaction (follow-up years × PCOS status) of PCOS and normal women converged overtime. Comparing third follow-up with first, insulin and HOMA-IR decreased 10.6% and 5%, respectively in PCOS women; and increased 6.7% and 14.6%, respectively in controls (P<0.05). The results did not show any significant result for other cardio-metabolic variables including WC, lipid profile, FPG, 2-h PG, SBP, and DBP.Conclusion
While the insulin level and insulin resistance rate were higher in reproductive aged PCOS than in healthy women, the difference of these risk factors decreased overtime. Thus, the metabolic consequences of PCOS women in later life may be lower than those initially anticipated. 相似文献112.
The new subfamily Iuiuniscinae, Styloniscidae, is erected for the new genus Iuiuniscus and the new species I. iuiuensis, which is described from cave of the State of Bahia, Northeastern Brazil. A special ecological character is shown here for the first time for a New World Oniscidea: the construction of mud shelters. An introduction addressing the systematics of Synocheta with emphasis on Styloniscidae Vandel, 1952 is provided, as well as general comments about the dependence of water in some Oniscidea and ecological traits of amphibious Synocheta. The problems referring to nomenclature, taxonomy and the interrelationships in Styloniscidae are discussed. 相似文献
113.
Fernanda A. H. Batista Leandro S. Goto Wanius Garcia Derminda I. de Moraes Mario de Oliveira Neto Igor Polikarpov Marcia R. Cominetti Heloísa S. Selistre-de-Araújo Leila M. Beltramini Ana Paula Ulian Araújo 《European biophysics journal : EBJ》2010,39(8):1193-1205
Lectins have been classified into a structurally diverse group of proteins that bind carbohydrates and glycoconjugates with
high specificity. They are extremely useful molecules in the characterization of saccharides, as drug delivery mediators,
and even as cellular surface makers. In this study, we present camptosemin, a new lectin from Camptosema ellipticum. It was characterized as an N-acetyl-d-galactosamine-binding homo-tetrameric lectin, with a molecular weight around 26 kDa/monomers. The monomers were stable over
a wide range of pH values and exhibited pH-dependent oligomerization. Camptosemin promoted adhesion of breast cancer cells
and hemagglutination, and both activities were inhibited by its binding of sugar. The stability and unfolding/folding behavior
of this lectin was characterized using fluorescence and far-UV circular dichroism spectroscopies. The results indicate that
chemical unfolding of camptosemin proceeds as a two-state monomer-tetramer process. In addition, small-angle X-ray scattering
shows that camptosemin behaves as a soluble and stable homo-tetramer molecule in solution. 相似文献
114.
In this paper, partitioning behaviors of typical neutral (Alanine), acidic (Glutamic acid) and basic (Lysine) amino acids
into imidazolium-based ionic liquids [C4mim][PF6], [C6mim][PF6], [C8mim][PF6], [C6mim][BF4] and [C8mim][BF4] as extracting solvents were examined. [C6mim][BF4] showed the best efficiency for partitioning of amino acids. The partition coefficients of amino acids in ionic liquids were
found to depend strongly on pH of the aqueous solution, amino acid and ionic liquid chemical structures. Different chemical
forms of amino acids in aqueous solutions were pH dependent, so the pH value of the aqueous phase was a determining factor
for extraction of amino acids into ionic liquid phase. Both water content of ionic liquids and charge densities of their anionic
and cationic parts were important factors for partitioning of cationic and anionic forms of amino acids into ionic liquid
phase. Extracted amino acids were back extracted into phosphate buffer solutions adjusted on appropriate pH values. The results
showed that ionic liquids could be used as suitable modifiers on the stationary phase of an HPLC column for efficient separation
of acidic, basic, and neutral amino acids. 相似文献
115.
Manel Ziadi Feriel Rezouga Hassib Bouallagui Leila Baâti Nada Ben Othman Philippe Thonart Moktar Hamdi 《World journal of microbiology & biotechnology》2010,26(12):2223-2230
The effect of controlled whey hydrolysis by papain on growth of two lactic acid bacteria isolated from artisanal Leben: Lactococcus lactis var. diacetylactis (SLT6 and SLT10) was investigated. The higher biomass and maximum specific growth rate (μ max) were obtained after 30 min of hydrolysis. HPLC analysis of peptides showed that whey hydrolysis reduced the amount of peptides of MW > 400 Da and increased those peptides of MW < 400 Da. The two studied strains exhibited different peptide requirements. The pH-controlled batch cultures in 30 min hydrolysed whey followed the Monod kinetic for growth and for lactate production. The values of the key kinetic constants were: maximum specific growth rate (μ max), 1.08 and 0.56 h?1; yield biomass on lactose (Y x/s), 0.20 and 0.18 g g?1 and saturation constant K s, 4.2 and 2.8 g L?1 for SLT6 and SLT10, respectively. When compared with batch experimental data, the model provided good predictions for growth, lactose utilisation and lactate production profiles. 相似文献
116.
Mohamed Ben Sghaier Jihed Boubaker Aicha Neffati Ilef Limem Ines Skandrani Wissem Bhouri Ines Bouhlel Soumaya Kilani Leila Chekir‐Ghedira Kamel Ghedira 《化学与生物多样性》2010,7(7):1754-1763
The mutagenic and antimutagenic effects of the essential oil extracted from the aerial parts of Teucrium ramosissimum were evaluated by the bacterial reverse mutation assay in Salmonella typhimurium TA98, TA100, and TA1535, with and without exogenous metabolic activation (S9 fraction). The T. ramosissimum essential oil showed no mutagenic effect. In contrast, our results established that it possessed antimutagenic effects against sodium azide (SA), aflatoxin B1 (AFB1), benzo[a]pyrene (B[a]P), and 4‐nitro‐o‐phenylenediamine (NOPD). The antioxidant capacity of the tested essential oil was evaluated using enzymatic, i.e., the xanthine/xanthine oxidase (X/XOD) assay, and nonenzymatic systems, i.e., the nitro‐blue tetrazolium (NBT)/riboflavin and the DPPH assays. A moderate free radical‐scavenging activity was observed towards DPPH. and O$\rm{{_{2}^{{^\cdot} -}}}$ . In contrast, T. ramosissimum essential oil showed no effect for all the tested concentrations in the X/XOD assay. 相似文献
117.
Mojtaba Amiri Leila Farzin Mohammad Esmail Moassesi Fattaneh Sajadi 《Biological trace element research》2010,135(1-3):38-44
Febrile convulsion is the most common disorder in childhood with good prognosis. There are different hypotheses about neurotransmitters and trace element changes in biological fluids which can have a role in pathogenesis of febrile convulsion. In this study, serum selenium, zinc, and copper were measured by atomic absorption spectrometry in the children with febrile convulsion (n?=?30) and in the control group (n?=?30). The age and sex of the subjects were registered. Selenium and zinc were found to be significantly lower in febrile convulsion cases than in the control group (p?<?0.0001 and p?<?0.0001, respectively). There was no significant difference in the value of copper between the two groups (p?=?0.16). While selenium and zinc levels were 44.92?±?10.93 μg/l and 66.13?±?18.97 μg/dl in febrile convulsion, they were found to be 62.98?±?9.80 μg/l and 107.87?±?28.79 μg/dl in healthy children. Meanwhile, copper levels were 146.40?±?23.51 μg/dl in the patients and 137.63?±?24.19 μg/dl in the control group, respectively. This study shows that selenium and zinc play an important role in the pathogenesis of febrile convulsion. 相似文献
118.
Ann-Christin Brorsson Gian Gaetano Tartaglia Giorgio Favrin David A. Lomas Michele Vendruscolo Damian C. Crowther Leila M. Luheshi 《Biophysical journal》2010,98(8):1677-1684
The extent to which proteins aggregate into distinct structures ranging from prefibrillar oligomers to amyloid fibrils is key to the pathogenesis of many age-related degenerative diseases. We describe here for the Alzheimer's disease-related amyloid β peptide (Aβ) an investigation of the sequence-based determinants of the balance between the formation of prefibrillar aggregates and amyloid fibrils. We show that by introducing single-point mutations, it is possible to convert the normally harmless Aβ40 peptide into a pathogenic species by increasing its relative propensity to form prefibrillar but not fibrillar aggregates, and, conversely, to abolish the pathogenicity of the highly neurotoxic E22G Aβ42 peptide by reducing its relative propensity to form prefibrillar species rather than mature fibrillar ones. This observation can be rationalized by the demonstration that whereas regions of the sequence of high aggregation propensity dominate the overall tendency to aggregate, regions with low intrinsic aggregation propensities exert significant control over the balance of the prefibrillar and fibrillar species formed, and therefore play a major role in determining the neurotoxicity of the Aβ peptide. 相似文献
119.
Stolf-Moreira R Medri ME Neumaier N Lemos NG Pimenta JA Tobita S Brogin RL Marcelino-Guimarães FC Oliveira MC Farias JR Abdelnoor RV Nepomuceno AL 《Genetics and molecular research : GMR》2010,9(4):1946-1956
Soybean genotypes MG/BR46 (Conquista) and BR16, drought-tolerant and -sensitive, respectively, were compared in terms of morphophysiological and gene-expression responses to water stress during two stages of development. Gene-expression analysis showed differential responses in Gmdreb1a and Gmpip1b mRNA expression within 30 days of water-deficit initiation in MG/BR46 (Conquista) plants. Within 45 days of initiating stress, Gmp5cs and Gmpip1b had relatively higher expression. Initially, BR16 showed increased expression only for Gmdreb1a, and later (45 days) for Gmp5cs, Gmdefensin and Gmpip1b. Only BR16 presented down-regulated expression of genes, such as Gmp5cs and Gmpip1b, 30 days after the onset of moisture stress, and Gmgols after 45 days of stress. The faster perception of water stress in MG/BR46 (Conquista) and the better maintenance of up-regulated gene expression than in the sensitive BR16 genotype imply mechanisms by which the former is better adapted to tolerate moisture deficiency. 相似文献
120.
Leila Hatami-Baroogh Shahnaz Razavi Hamid Zarkesh-Esfahani Marziyeh Tavalaee Somayeh Tanhaei Kamran Ghaedi Mohamad Reza Deemeh Farzaneh Rabiee Mohammad Hossein Nasr-Esfahani 《Reproductive biology and endocrinology : RB&E》2010,8(1):17