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991.
992.
Zahra N. Sohani Sonia S. Anand Sebastien Robiou-du-Pont Katherine M. Morrison Sarah D. McDonald Stephanie A. Atkinson Koon K. Teo David Meyre 《PloS one》2016,11(4)
BackgroundMetabolic abnormalities that lead to type 2 diabetes mellitus begin in early childhood.ObjectivesWe investigate whether common genetic variants identified in adults have an effect on glucose in early life.Methods610 newborns, 463 mothers, and 366 fathers were included in the present study. Plasma glucose and anthropometric characteristics were collected at birth, 3, and 5 years. After quality assessment, 37 SNPs, which have demonstrated an association with fasting plasma glucose at the genome-wide threshold in adults, were studied. Quantitative trait disequilibrium tests and mixed-effects regressions were conducted to estimate an effect of the SNPs on glucose.ResultsRisk alleles for 6 loci increased glucose levels from birth to 5 years of age (ADCY5, ADRA2A, CDKAL1, CDKN2A/B, GRB10, and TCF7L2, 4.85x10-3 ≤ P ≤ 4.60x10-2). Together, these 6 SNPs increase glucose by 0.05 mmol/L for each risk allele in a genotype score (P = 6.33x10-5). None of the associations described in the present study have been reported previously in early childhood.ConclusionOur data support the notion that a subset of loci contributing to plasma glucose variation in adults has an effect at birth and in early life. 相似文献
993.
Parvane Saneei Ahmad Esmaillzadeh Ammar Hassanzadeh Keshteli Hamid Reza Roohafza Hamid Afshar Awat Feizi Peyman Adibi 《PloS one》2016,11(1)
Background and Aims
Joint association of lifestyle-related factors and mental health has been less studied in earlier studies, especially in Middle Eastern countries. This study aimed to examine how combinations of several lifestyle-related factors related to depression and anxiety in a large group of middle-age Iranian population.Methods
In a cross-sectional study on 3363 Iranian adults, a healthy lifestyle score was constructed by the use of data from dietary intakes, physical activity, smoking status, psychological distress and obesity. A dish-based 106-item semi-quantitative validated food frequency questionnaire (FFQ), General Practice Physical Activity Questionnaire (GPPAQ), General Health Questionnaire (GHQ) and other pre-tested questionnaires were used to assess the components of healthy lifestyle score. The Hospital Anxiety and Depression Scale (HADS) was applied to screen for anxiety and depression.Results
After adjustment for potential confounders, we found that individuals with the highest score of healthy lifestyle were 95% less likely to be anxious (OR: 0.05; 95% CI: 0.01–0.27) and 96% less likely to be depressed (OR: 0.04; 95% CI: 0.01–0.15), compared with those with the lowest score. In addition, non-smokers had lower odds of anxiety (OR: 0.64; 95% CI: 0.47–0.88) and depression (OR: 0.62; 95% CI: 0.48–0.81) compared with smokers. Individuals with low levels of psychological distress had expectedly lower odds of anxiety (OR: 0.13; 95% CI: 0.10–0.16) and depression (OR: 0.10; 95% CI: 0.08–0.12) than those with high levels. Individuals with a healthy diet had 29% lower odds of depression (OR: 0.71; 95% CI: 0.59–0.87) than those with a non-healthy diet.Conclusion
We found evidence indicating that healthy lifestyle score was associated with lower odds of anxiety and depression in this group of Iranian adults. Healthy diet, psychological distress, and smoking status were independent predictors of mental disorders. 相似文献994.
Stereochemical Properties of Multidentate Nitrogen Donor Ligands and Their Copper Complexes by Electronic CD and DFT
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UV–Vis and electronic circular dichroism (ECD) spectroscopy, complemented with Density Functional Theory (DFT) calculations, were used to elucidate the structural diversities of three multidentate nitrogen donor ligands and two associated copper complexes in solution directly. The three chiral salen ligands all consist of trans‐cyclohexane‐1,2‐diamine as a chiral scaffold and also of pyridine rings as chromophores, differing only in the linking groups between the two functional groups mentioned above. Very different ECD intensities and somewhat different ECD patterns were observed for these ligands and satisfactorily interpreted theoretically. For the geometry optimization and spectral simulation of the open‐shell metal complexes, the LANL2DZ basis set with effective core potential for the Cu and Cl atoms and pure cc‐pVTZ for the rest of the atoms was utilized. The performance of the same calculations with the polarization functions (f,g) from the cc‐pVTZ basis added to the LANL2DZ basis was compared. While the three ligands exhibit different conformational flexibility, the associated copper complexes show great rigidity imposed by the metal–ligand coordination, taking on a single structure in each case. In addition, dispersion interactions were shown to change the conformational stability ordering of the ligands noticeably and to exert considerable influence on the simulated UV–Vis and ECD spectra. Chirality 28:545–555, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
995.
Zahra Lari Narges Moradi-kheibari Hossein Ahmadzadeh Parvaneh Abrishamchi Navid R. Moheimani Marcia A. Murry 《Journal of applied phycology》2016,28(6):3235-3250
Microalgae have been used commercially as a feedstock for the production of high-value compounds, pigments, cosmetics, and nutritional supplements. In addition, because of their rapid growth rates, high photosynthetic efficiency, and high lipid and protein content, commodity products including biodiesel, feed supplements, and polyunsaturated fatty acids derived from algal biomass are of current interest. Since microalgae lack non-photosynthetic structures and float in water, they do not need massive amounts of structural cellulose found in land plants. Thus, under optimal culture conditions, some oleaginous species can allocate up to 70 % of their biomass to lipids. Lipid production and its regulation in microalgae are species-specific and influenced by environmental conditions. Various strategies have been developed to improve lipid productivity and fatty acid composition to meet specific production goals. Manipulation of physiochemical parameters, trophic modes, and nutrient levels, known as process engineering, is a simple approach that leads to desired alterations in the biochemical composition of algal biomass, including lipid quantity and quality. In this paper, we review the effects of manipulating biochemical parameters such as necessary nutrients (C, N, P, S, Fe, and Si), NaCl concentration, and pH of culture medium to optimize lipid content and profile in some algae strains with commercial potential. 相似文献
996.
997.
Khodaiyan F Razavi SH Emam-Djomeh Z Mousavi SM Hejazi MA 《Journal of microbiology and biotechnology》2007,17(2):195-201
This study investigated the effects of various culture parameters (carbon sources, temperature, initial pH of culture, NaCl concentration, and light) on the growth and canthaxanthin production by Dietzia natronolimnaea HS-1. The results showed that the most effective carbon source for growth and canthaxantin production was glucose, and the best pH and temperature were 7 and 31 degrees C, respectively. In addition, the biomass and canthaxanthin production increased in a medium without NaCl and in the presence of light. Under the optimized conditions, the maximum biomass, total carotenoid, and canthaxanthin production were 6.12 +/- 0.21 g/l, 4.51 +/- 0.20 mg/l, and 4.28 +/- 0.15 mg/l, respectively, in an Erlenmeyer flask system, yet increased to 7.25 g/l, 5.48 mg/l, and 5.29 mg/l, respectively, in a batch fermenter system. 相似文献
998.
Safaralizadeh R Sirjani M Pourpak Z Kardar G Teimourian S Shams S Namdar Z Kazemnejad A Moin M 《BioFactors (Oxford, England)》2007,31(2):127-131
INTRODUCTION: Selenium is one of the essential trace elements which is more notified in children in recent years. Reliable age-specific reference values for selenium in children in Iran are not clear and are important for the identification of selenium deficiency and some other researches that is the aim of this study. METHODS: Serum samples of 216 healthy children were analyzed by using hydride generation and flame atomic absorption spectroscopy to measured selenium level. RESULTS: The mean and standard deviation of serum selenium level in children 0-16 years old (mean: 39.83 months) was 72.14+/-16.80 microg/l. There was significant difference in serum selenium concentration between two sexes which was 76.78+/-15.24 microg/l and 69.56+/-17.09 microg/l in girls and boys respectively (P value=0.002). There was also a positive correlation between higher selenium serum concentration and age in both sexes. CONCLUSION: Essential trace element's normal ranges are fundamental data which could use in many studies. Serum selenium concentration in healthy Iranian children that found in this study is very close to serum concentration of European children. Our findings may reveal nutritional culture's similarity. 相似文献
999.
Culture of Helicobacter pylori from stool samples in children 总被引:1,自引:0,他引:1
Falsafi T Valizadeh N Najafi M Ehsani A Khani A Landarani Z Falahi Z 《Canadian journal of microbiology》2007,53(3):411-416
We evaluated two protocols for isolation of Helicobacter pylori in stool from biopsied and nonbiopsied children. Twenty-three child patients whose presumptive positivity or negativity was diagnosed by endoscopy and a rapid urease test at site were used to compare biopsy-based tests with stool-based tests (H. pylori stool antigen test and stool culture). Their gastric activity and bacterial density were graded by the updated Sydney system. Biopsy and stool specimens were cultured on Campy-blood and Belo horizonte agar plates after enrichment in selective Campy-Thio medium. To compare two stool culture protocols, stools from 20 nonbiopsied children were tested by the HpSA test and cultured either as above or after treatment with cholestyramine. Grown colonies were screened by Gram staining, slide agglutination using anti-H. pylori monoclonal IgG; positive isolates were tested by biochemical tests and polymerase chain reaction for H. pylori-specific ureA gene. Coccoid H. pylori was isolated in stool samples from the biopsied patients whose bacterial density was two to four in histology. Their oxidase was slightly positive but became positive after two subcultures, while additional biochemical tests confirmed the isolation of H. pylori. Similar coccoid but oxidase positive H. pylori was isolated from three nonbiopsied children with the protocol of cholestyramine treatment only. The density of bacteria in the stomach may influence the recovery of H. pylori from stool; inactivation of bile with cholestyramine improves the yield in culture and favors isolation of an enhanced metabolic form of bacteria. 相似文献