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51.
The CD spectra of the series PhCH(Me)R, with R = Et (1), nPr (2), iPr (3), and tBu (4), are reported (1-3 for the first time) at room temperature in the 185-280 nm range and at 183 K. These purely hydrocarbon compounds represent the simplest chiral systems containing the phenyl chromophore and exhibit Cotton effects exclusively allied with the benzene transitions. The bands in 1La and 1Lb regions were checked against the available sector rules, with discordant outcomes. Time-dependent density-functional theory calculations, with various functionals and basis sets tested, correctly reproduced the prominent CD bands observed for 1-4. 相似文献
52.
Rahman A Azad MA Hossain I Qusar MM Bari W Begum F Huq SM Hasnat A 《Biological trace element research》2009,127(2):102-108
The purpose of the study was to determine the concentration of trace elements present in scalp hair sample of schizophrenic
patients and to find out the relationship between trace elements level and nutritional status or socioeconomic factors. The
study was conducted among 30 schizophrenic male patients and 30 healthy male volunteers. Patients were recruited from Bangabandhu
Sheikh Mujib Medical University by random sampling. Hair trace element concentrations were determined by flame atomic absorption
spectroscopy and analyzed by independent t test, Pearson’s correlation analysis, regression analysis, and analysis of variance (ANOVA). Mn, Zn, Ca, Cu, and Cd concentrations
of schizophrenic patients were 3.8 ± 2.31 μg/gm, 171.6 ± 59.04 μg/gm, 396.23 ± 157.83 μg/gm, 15.40 ± 5.68 μg/gm, and 1.14 ± 0.89 μg/gm
of hair sample, while those of control subjects were 4.4 ± 2.32 μg/gm, 199.16 ± 27.85 μg/gm, 620.9 ± 181.55 μg/gm, 12.23 ± 4.56 μg/gm,
and 0.47 ± 0.32 μg/gm of hair sample, respectively. The hair concentration of Zn and Ca decreased significantly (p = 0.024; p = 0.000, respectively) and the concentration of Cu and Cd increased significantly (p = 0.021; p = 0.000, respectively) in schizophrenic patients while the concentration of Mn (p = 0.321) remain unchanged. Socioeconomic data reveals that most of the patients were poor, middle-aged and divorced. Mean
body mass indices (BMIs) of the control group (22.26 ± 1.91 kg/m2) and the patient group (20.42 ± 3.16 kg/m2) were within the normal range (18.5−25.0 kg/m2). Pearson’s correlation analysis suggested that only Ca concentration of patients had a significant positive correlation
with the BMI (r = 0.597; p = 0.000) which was further justified from the regression analysis (R
2 = 44%; t = 3.59; p = 0.002) and one-way ANOVA test (F = 3.62; p = 0.015). A significant decrease in the hair concentration of Zn and Ca as well as a significant increase in the hair concentration
of Cu and Cd in schizophrenic patients than that of its control group was observed which may provide prognostic tool for the
diagnosis and treatment of this disease. However, further work with larger population is suggested to examine the exact correlation
between trace element level and the degree of disorder. 相似文献
53.
Paola Venditti Angela Bari Lisa Di Stefano Sergio Di Meo 《Free radical biology & medicine》2009,46(3):360-366
We investigated whether swim training modifies the effect of T3-induced hyperthyroidism on metabolism and oxidative damage in rat muscle. Respiratory capacities, oxidative damage, levels of antioxidants, and susceptibility to oxidative challenge of homogenates were determined. Mitochondrial respiratory capacities, H2O2 release rates, and oxidative damage were also evaluated. T3-treated rats exhibited increases in muscle respiratory capacity, which were associated with enhancements in mitochondrial respiratory capacity and tissue mitochondrial protein content in sedentary and trained animals, respectively. Hormonal treatment induced muscle oxidative damage and GSH depletion. Both effects were reduced by training, which also attenuated tissue susceptibility to oxidative challenge. The changes in single antioxidant levels were slightly related to oxidative damage extent, but the examination of parameters affecting the susceptibility to oxidants indicated that training was associated with greater effectiveness of the muscle antioxidant system. Training also attenuated T3-induced increases in H2O2 production and, therefore, oxidative damage of mitochondria by lowering their content of autoxidizable electron carriers. The above results suggest that moderate training is able to reduce hyperthyroid state-linked tissue oxidative damage, increasing antioxidant protection and decreasing the ROS flow from the mitochondria to the cytoplasmic compartment. 相似文献
54.
Biotransformation of tea catechins into theaflavins with immobilized polyphenol oxidase 总被引:2,自引:0,他引:2
Kapil Sharma Shamsher S. Bari Harsh P. Singh 《Journal of Molecular Catalysis .B, Enzymatic》2009,56(4):253-258
Theaflavins, an active antioxidant, a natural pigment and pharmacologically active molecule obtained from black tea were bioprocessed on an immobilized tea polyphenol oxidase (PPO) system by the conversion of tea catechins extracted from green tea leaves with an overall conversion efficiency of 85% about 14-fold increase over maximum achievable in normal black teas. The immobilized enzyme (IE) system consists of activated cellulose matrix on to which the freshly extracted tea leaf polyphenol oxidase was covalently linked. Cellulose as a matrix of choice was considered primarily for its non-toxic nature, natural origin, low cost and easy availability. The kinetic parameters of the IE system were; protein loading capacity 11.8 mg/g; pH optimum 5.9; temperature optimum 37.5 °C; Km 4.76 ± 0.08 mM; Vmax 20 ± 1.80 nmol/min; enzyme activity retention (83.58%) and number of batches per turnover without loss of activity was 14. The product from IE system was identified by HPLC and ESI-QTOF-MS spectrometry. 相似文献
55.
56.
Piening N Nonno R Di Bari M Walter S Windl O Agrimi U Kretzschmar HA Bertsch U 《The Journal of biological chemistry》2006,281(14):9373-9384
The misfolded infectious isoform of the prion protein (PrP(Sc)) is thought to replicate in an autocatalytic manner by converting the cellular form (PrP(C)) into its pathogenic folding variant. The similarity in the amino acid sequence of PrP(C) and PrP(Sc) influences the conversion efficiency and is considered as the major determinant for the species barrier. We performed in vitro conversion reactions on wild-type and mutated PrP(C) to determine the role of the primary sequence for the high susceptibility of bank voles to scrapie. Different conversion efficiencies obtained with bank vole and mouse PrP(C) in reactions with several prion strains were due to differences at amino acid residues 155 and 170. However, the conversion efficiencies obtained with mouse and vole PrP(C) in reactions with sheep scrapie did not correlate with the susceptibility of the respective species to this prion strain. This discrepancy between in vitro and in vivo data may indicate that at least in the case of scrapie transmission to bank voles additional host factors can strongly modulate the species barrier. Furthermore, in vitro conversion reactions with different prion strains revealed that the degree of alteration of the conversion efficiency induced by amino acid exchanges was varying according to the prion strain. These results support the assumption that the repertoire of conformations adopted by a certain PrP(C) primary sequence is decisive for its convertibility to the strain-specific PrP(Sc) conformation. 相似文献
57.
Ozener B 《Collegium antropologicum》2011,35(4):1001-1005
Perturbations during development leave enduring signs on the adult body. Fluctuating asymmetry (FA) is a good bio-indicator of stress during ontogeny. The aim of this study is to determine the effect of urban poverty on the fluctuating asymmetry of young Turkish males. Young males from a lower socioeconomic group (N = 140, Mean age = 18.17 +/- 0.61) were selected from slum areas of Ankara, the capital of Turkey, where urban poverty is intense. An upper socioeconomic group, on the other hand, consisted of students from two private colleges and included children from some of the richest families in Turkey (N = 120, Mean age = 18.08 +/- 0.54). Eight anthropometric traits of all subjects were measured. Considering the seven measurements demonstrate ideal FA, the individuals living in poor areas of the city displayed higher FA. The discrepancy between the two groups was even greater for a measure of composite FA. In conclusion, poor living conditions in Ankara, where urban poverty is intense, adversely impact the developmental stability of young Turkish males. 相似文献
58.
M J Kogan M E Mora S E Bari J Iturraspe J Awruch J M Delfino 《Bioorganic & medicinal chemistry》1999,7(7):1309-1319
Unlike bilirubin IXalpha (1), the isomers bilirubin IXdelta (2) and neobilirubin IXbeta (3) do not require conjugation with glucuronic acid in order to be excreted. A conformational analysis employing an optimized Monte Carlo method and a mixed Monte Carlo stochastic dynamics reveals that isomer 2 exhibits a structure more closed than the well known 'ridge-tile' conformation of 1. The change in the position of both propionic acid chains causes the loss of at least four hydrogen bonds. On the other hand, the change in the configuration of the distal dipyrrinone and the blockage of the lactamic nitrogen by the presence of a bridge in isomer 3 results in an open and more elongated structure, where the chance of hydrogen bond formation in this region is obliterated. The resulting molecular models for these compounds are consistent with 1H NM R, UV-vis, and TLC data. 相似文献
59.
Incorporation and intraparticulate hydrolysis of 131 I-albumin by liver and kidney of an amphibian (Bufo arenarum) 总被引:1,自引:0,他引:1
After a single injection of formaldehyde-treated 131 I-albumin into the heart, the incorporation of the labelled protein by liver (% of total injected radioactivity/% of body weight of the organ) was far greater than in other organs. In kidney and spleen it was respectively six and three times greater than in lungs, intestine, testis and fatty body. No radioactivity was found in brain. The radioactivity in liver and kidney reached a peak 30 minutes after the injection, and quickly decreased during the following four hours. In the 27,000 g × ten minute particles recovered from liver homogenates of animals sacrificed at various times after injection, the rate of 131 I-albumin hydrolysis in vitro and the percentage of trichloroacetic acid soluble radioactivity at zero time of incubation showed different stages of intraparticulate hydrolytic activity. The incorporation and intraparticulate hydrolysis in toad kidney was very low if compared with that of toad liver or mouse kidney; however the catheptic specific activity in toad kidney doubles that of mouse kidney. Isolated toad liver was perfused with total blood, containing 131 I-albumin, for five hours at 22°C in a special chamber. In this conditions, 16% of the labelled albumin was hydrolyzed by the liver. 相似文献
60.
Habibul Bari Shozib Md. Mariful Islam Sultan Abu Saleh Mahmud Md. Nazmul Bari Nasima Akter Saima Jahan Shakir Hosen Mohammad Nazir Hossain A.H.M. Nurun Nabi Muhammad Ali Siddiquee Md. Manjurul Haque 《Saudi Journal of Biological Sciences》2021,28(12):7472-7480
BackgroundBlack pericarp rice has recently become popular among rice consumers for its diverse health benefits specially anti-cancer effect. Cyanidin-3-Glucosides (C3G), an prominant bioactive component of anthocyanins which is abundantly present in black pericarp rice.ObjectivesWe investigated, how effectively it can be used to fortify Cyanidin-3-Glucosides (C3G) content in red and white pericarp polished rice or rice based bakery products for more nutritional value.MethodIn the present study, we have characterized several black pericarp rice cultivars along with some red pericarp and white pericarp rice cultivars by physicochemical including mineral profiling, and quantified the C3G by UFLC and LCMS.ResultsC3G content was significantly reduced from raw rice to cooked rice condition. All the black pericarp rice cultivars synthesized C3G, while this content was not detected in red and white pericarp rice cultivars. However, when 25% of black pericarp rice were mixed with 75% red or white pericarp polished rice, C3G content was significantly retained in cooked rice conditions. Formulation of rice-based bakery food product using black pericarp rice powder was also remarkably retained the C3G content as compared to that of cooking. Black rice is harder in texture, difficult to digest and needs higher energy for cooking. Therefore, we tried to circumvent these challenges by fortifying 25% of black pericarp rice with white or red pericarp rice.ConclusionFortification of C3G enriched black rice (25%) with red or white pericarp rice (75%) might bring a better nutritional quality in both cooking and baking condition. This may lead a way to the effective management of the non-communicable disease such as cancer for common rice consuming population. 相似文献