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141.
142.
Both the trans and cis isomers of [Ru(acac)2{P(OMe)3}2] were isolated in the form of single crystals and characterized by single crystal X-ray diffraction, UV-Vis, MS, 1H, 13C and 31P NMR spectroscopy. The compounds of ruthenium(II), both mononuclear complexes, crystallize in triclinic space group. The metal ion in both compounds has similar, slightly distorted octahedral coordination geometry. Both complexes were tested as catalyst in hydrogen generation from the hydrolysis of sodium borohydride. When used alone, none of the trans- and cis-[Ru(acac)2{P(OMe)3}2] complexes shows significant catalytic activity. However, the catalytic activity of cis-[Ru(acac)2{P(OMe)3}2] in the hydrolysis of sodium borohydride is significantly enhanced by the addition of two equivalents of trimethylphosphite per ruthenium into the medium. 相似文献
143.
144.
Phloridzin reduces blood glucose levels and improves lipids metabolism in streptozotocin-induced diabetic rats 总被引:2,自引:0,他引:2
Najafian M Jahromi MZ Nowroznejhad MJ Khajeaian P Kargar MM Sadeghi M Arasteh A 《Molecular biology reports》2012,39(5):5299-5306
Phloridzin is the specific and competitive inhibition of sodium/glucose cotransporters in the intestine (SGLT1) and kidney
(SGLT2). This property which could be useful in the management of postprandial hyperglycemia in diabetes and related disorders.
Phloridzin is one of the dihydrochalcones typically contained in apples and in apple-derived products. The effect of phloridzin
orally doses 5, 10, 20 and 40 mg/kg body weight on diabetes was tested in a streptozotocin-induced rat model of diabetes type
1. From beneficial effect of this compound is significant reduction of blood glucose levels and improve dyslipidemia in diabetic
rats. As a well-known consequence of becoming diabetic, urine volume and water intake were significantly increased. Administration
of phloridzin reduced urine volume and water intake in a dose-dependent manner. Phloretin decreases of food consumption, as
well as a marked lowering in the weight. In conclusion, this compound could be proposed as an antihyperglycemic and antihyperlipidemic
agent in diabetes and potential therapeutic in obesity. 相似文献
145.
Shahid S Abid A Mehdi SQ Mehdi QS Firasat S Lanewala A Naqvi SA Naqvi AA Rizvi SA Rizvi AU Khaliq S 《Gene》2012,493(1):165-168
Nephrotic syndrome is a common pediatric glomerular disease associated with heavy proteinuria. Since, the angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism is a putative genetic risk factor for NS, in this study, ACE (I/D) polymorphism was analyzed in 268 NS and 223 control samples by a PCR-based method. The genotypic and allelic frequencies were determined and the association between ACE I/D polymorphism and NS was evaluated. The frequency distribution of the II, ID and DD genotypes was 82 (30.6%), 128 (47.8%) and 58 (21.6%) in the NS patients and 9 (4.0%), 171 (76.7%) and 43 (19.3%) in the control samples respectively. In the Pakistani pediatric NS population, the II genotypic and allelic frequencies were found to be significantly associated with the disease (OR = 6.755; C.I = 3-14.9). No significant association was found between this polymorphism and the response to standard steroid therapy. Thus, in contrast to reports from other parts of the world, the II genotype was found to be significantly associated with NS in the Indian and Malay populations and in the Pakistani population described here. To our knowledge, this is the first report from Pakistan describing the association of the ACE I/D polymorphism with pediatric NS. On the basis of these results, it is suggested that analysis of the ACE (I/D) polymorphism should be performed for the early diagnosis in the high risk NS patients in South Asia. 相似文献
146.
Introduction
Thyroid peroxidase (TPO) gene variations are one cause of thyroid autoimmune diseases. The aim of this study was to examine the association between the T1936C, T2229C and A2257C polymorphisms of the TPO gene and Anti-TPO level.Materials and methods
In this case–control study, 188 individuals (86 males and 102 females), aged 20–80 years, were randomly selected from among the Tehran Lipid and Glucose Study (TLGS) population. A2257C and T2229C SNPs were detected with RFLP by use of BsrI and Eco57I as the restriction enzymes respectively, while the T1936C SNP was determined with ARMS-PCR.Results
In the presence of the C allele of T1936C, Anti-TPO level was significantly increased (CC: 238 ± 43.3, CT: 47.7 ± 15.9, TT: 74.1 ± 11.3 IU/L p = 0.002); however, this association was attenuated after adjustment for sex and age (p = 0.059). No significant difference, before and after adjustment, was found in Anti-TPO level in the presence of T2229C SNP (CC: 129.1 ± 24.5, CT: 43.5 ± 12.6, TT: 126.5 ± 13.8 IU/L p = 0.196). The association between A2257C and Anti-TPO level was only significant after adjustment for potential confounders (p = 0.007). The association between ATC and CTT haplotypes and Anti-TPO level was significant (p = 0.023, 0.021 respectively), the association between CTT and Anti-TPO concentration was also significant after adjustment for sex (p = 0.014).Conclusion
The results of the present study confirmed the association between TPO gene polymorphisms and Anti-TPO level in the Tehranian population. 相似文献147.
DNA hybridization and enzymatic digestion for the detection of mutation was investigated on the gold nanoparticles-calf thymus DNA (AuNPs-ctDNA) modified glassy carbon electrode (GCE). The thiol modified probe oligonucleotides (SH-ssDNA) were assembled on the surface of AuNPs-ctDNA modified GCE. The electrochemical response of the electrode was measured by differential pulse voltammetry and cyclic voltammetry. Methylene blue (MB) was used as the electroactive indicator. AuNPs were then dispersed effectively on the GCE surface in the presence of ct-DNA. When hybridization occurred, a decrease in the signal of MB current was observed. The modified electrode was used for the detection of mutations during the enzymatic digestion reaction in DNA. During this reaction, an increase in the signal of MB current was observed. So, the modified SH-ssDNA had a higher electrochemical response on the AuNPs-ctDNA/GCE because of the strong affinity of MB for guanine residues in it. The electrochemical detection of restriction enzyme digestion can provide a simple and practical method for observing single-base mismatches that can help in distinguishing mismatch sequences of DNA from the complementary ones. 相似文献
148.
Azadvar Mehdi Virendra Kumar Baranwal Madhavan Kochu Babu Deepthi Praveena 《Journal of Phytopathology》2012,160(1):6-12
During January 2010, severe stunting symptoms were observed in clonally propagated oil palm (Elaeis guineensis Jacq.) in West Godavari district, Andhra Pradesh, India. Leaf samples of symptomatic oil palms were collected, and the presence of phytoplasma was confirmed by nested polymerase chain reaction (PCR) using universal phytoplasma‐specific primer pairs P1/P7 followed by R16F2n/R16R2 for amplification of the 16S rRNA gene and semi‐nested PCR using universal phytoplasma‐specific primer pairs SecAfor1/SecArev3 followed by SecAfor2/SecArev3 for amplification of a part of the secA gene. Sequencing and BLAST analysis of the ~1.25 kb and ~480 bp of 16S rDNA and secA gene fragments indicated that the phytoplasma associated with oil palm stunting (OPS) disease was identical to 16SrI aster yellows group phytoplasma. Further characterization of the phytoplasma by in silico restriction enzyme digestion of 16S rDNA and virtual gel plotting of sequenced 16S rDNA of ~1.25 kb using iPhyClassifier online tool indicated that OPS phytoplasma is a member of 16SrI‐B subgroup and is a ‘Candidatus Phytoplasma asteris’‐related strain. Phylogenetic analysis of 16S rDNA and secA of OPS phytoplasma also grouped it with 16SrI‐B. This is the first report of association of phytoplasma of the 16SrI‐B subgroup phytoplasma with oil palm in the world. 相似文献
149.
M Sedighi M Ghasemi SH Hassan WR Daud M Ismail E Abdallah 《World journal of microbiology & biotechnology》2012,28(5):2047-2055
Response surface methodology (RSM) based on central composite rotatable design was used to investigate the effects of operating
variable, mainly, pH, weight of biomass, and initial lead ion concentration on the lead adsorption capacity at ambient temperature
using dried cells of Lactobacillius bulgaricus. Using RSM, quadratic polynomial equation was obtained for predicting the percent of lead ion removal. Analysis of variance
showed that the effects of pH and weight of dried biomass were concluded to be the key factors influencing the capacity of
lead ion removal. At pH lower than 2 (high acidic condition) and in alkaline condition, there is no significant biosorption.
The optimum percent of lead ion removal was found at pH of 6.78, biomass concentration of 6.58 g/l and initial lead concentration
36.22 ppm. In this condition, percent of lead ion removal was 86.21%. This study showed RSM effectiveness for modeling of
biosorption process. 相似文献
150.