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51.
The reticulocytes and the ageing red blood cells (RBCs) namely young (Y), middle-aged (M) and old RBCs (O) of female Wistar
rats from different groups such as control animals (C), controls treated with vanadate (C + V), alloxan-induced diabetic (D),
diabetic-treated with insulin (D + I) and vanadate (D + V), were fractionated on a percoll/BSA gradient. The following enzymes
were measured-hexokinase (HK), glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R), glutathione-s-transferase
(GST), alanine aminotransferase ΜlaAT), aspartate aminotransferase ΜsAT) and arginase in the hemolysates of all the RBCs fractions.
Decreases in the activity of HK and AsAT by about 70%, arginase and GSH-Px by 30% in old RBCs were observed in comparison
to reticulocytes of control animals. Increases in the activity of GSSG-R by 86%, AlaAT by more than 400% and GST by 70% were
observed in old RBCs in comparison to reticulocytes of control animals.
Alloxan diabetic animals showed a further decrease in the activities of HK in Y RBCs by 37%, M RBCs by 39% and O RBCs by 32%,
GSH-Px activity in Y RBCs by 13%, M RBCs by 20% and O RBCs by 33% and GST activity in Y RBCs by 14%, M RBCs by 42% and O RBCs
by 60% in comparison to their corresponding cells of control animals. An increase in the activity of all the enzymes studied
was also observed in reticulocytes of diabetic animals in comparison to reticulocytes of controls. The GSSG-R activity was
found to be increased in Y RBCs by 49%, M RBCs by 67% and O RBCs by 64% as compared to the corresponding age-matched cells
of control animals. The activity of arginase also decreased in Y RBCs by about10%, M RBCs by 20% and O RBCs by 30% in comparison
to the age-matched cells of control animals. A decrease in the activity of AsAT in Y and M RBCs by 30%, and O RBCs by 25%
was observed in diabetic animals in comparison to the agematched cells of control animals. The activity of AlaAT was found
to be decreased by more than 10% in Y and M RBCs and 25% in O RBCs of diabetic animals in comparison to the age-matched cells
of control animals.
Insulin administration to diabetic animals reversed the altered enzyme activity to control values. Vanadate treatment also
reversed the enzyme levels except for that of GST in old cells 相似文献
52.
Evelin Despot-Slade Brankica Mravinac Saa irca Philippe Castagnone-Sereno Miroslav Plohl Nevenka Metrovi 《Molecular biology and evolution》2021,38(5):1943
Although centromeres have conserved function, centromere-specific histone H3 (CenH3) and centromeric DNA evolve rapidly. The centromere drive model explains this phenomenon as a consequence of the conflict between fast-evolving DNA and CenH3, suggesting asymmetry in female meiosis as a crucial factor. We characterized evolution of the CenH3 protein in three closely related, polyploid mitotic parthenogenetic species of the Meloidogyne incognita group, and in the distantly related meiotic parthenogen Meloidogyne hapla. We identified duplication of the CenH3 gene in a putative sexual ancestral Meloidogyne. We found that one CenH3 (αCenH3) remained conserved in all extant species, including in distant Meloidogyne hapla, whereas the other evolved rapidly and under positive selection into four different CenH3 variants. This pattern of CenH3 evolution in Meloidogyne species suggests the subspecialization of CenH3s in ancestral sexual species. Immunofluorescence performed on mitotic Meloidogyne incognita revealed a dominant role of αCenH3 on its centromere, whereas the other CenH3s have lost their function in mitosis. The observed αCenH3 chromosome distribution disclosed cluster-like centromeric organization. The ChIP-Seq analysis revealed that in M. incognita αCenH3-associated DNA dominantly comprises tandem repeats, composed of divergent monomers which share a completely conserved 19-bp long box. Conserved αCenH3-associated DNA is also confirmed in the related mitotic Meloidogyne incognita group species suggesting preservation of both centromere protein and DNA constituents. We hypothesize that the absence of centromere drive in mitosis might allow for CenH3 and its associated DNA to achieve an equilibrium in which they can persist for long periods of time. 相似文献
53.
Amarnath Singh Ritul Kamal Mohana Krishna Reddy Mudiam Manoj Kumar Gupta Gubbala Naga Venkata Satyanarayana Vipin Bihari Nishi Shukla Altaf Hussain Khan Chandrasekharan Nair Kesavachandran 《PloS one》2016,11(2)
Indoor air quality and heat exposure have become an important occupational health and safety concern in several workplaces including kitchens of hotels. This study investigated the heat, particulate matter (PM), total volatile organic compounds (TVOCs) and polycyclic aromatic hydrocarbons (PAHs) emissions in indoor air of commercial kitchen and its association with kidney dysfunctions among kitchen workers. A cross sectional study was conducted on 94 kitchen workers employed at commercial kitchen in Lucknow city, North India. A questionnaire-based survey was conducted to collect the personal and occupational history of the kitchen workers. The urine analysis for specific gravity and microalbuminuria was conducted among the study subjects. Indoor air temperature, humidity, wet/ dry bulb temperature and humidex heat stress was monitored during cooking activities at the kitchen. Particulate matter (PM) for 1 and 2.5 microns were monitored in kitchen during working hours using Hazdust. PAHS in indoor air was analysed using UHPLC. Urinary hydroxy-PAHs in kitchen workers were measured using GC/MS-MS. Higher indoor air temperature, relative humidity, PM1 and PM2.5 (p<0.001) was observed in the kitchen due to cooking process. Indoor air PAHs identified are Napthalene, fluorine, acenaphthene, phenanthrene, pyrene, chrysene and indeno [1,2,3-cd) pyrene. Concentrations of all PAHs identified in kitchen were above the permissible OSHA norms for indoor air. Specific gravity of urine was significantly higher among the kitchen workers (p<0.001) as compared to the control group. Also, the prevalence of microalbuminuria was higher (p<0.001) among kitchen workers. Urinary PAH metabolites detected among kitchen workers were 1-NAP, 9-HF, 3-HF, 9-PHN and 1-OHP. Continuous heat exposure in kitchens due to cooking can alter kidney functions viz., high specific gravity of urine in kitchen workers. Exposure to PM, VOCs and PAHs in indoor air and presence of urinary PAHs metabolites may lead to inflammation, which can cause microalbuminuria in kitchen workers, as observed in the present study. 相似文献
54.
55.
The yeast cells of Pichia farinosa Y-118 were immobilized in polyacrylamide gel and used for 17 beta-oxidoreduction of secondione to secol. The loss of hydroxysteroid oxidoreductase activity of cells was found to be insignificant during immobilization. The preparation exhibited greater temperature stability as compared to free cells. The ratio of reaction volume to the volume of immobilized biocatalyst in the range 1.4-1.9 was found to be satisfactory for the reaction conditions studied. This ratio played a significant role in the stability of the catalyst particle, since beyond a critical value the disintegration of gel granules was rapid resulting in sharp decline of activity. The immobilized cell preparation could be used 50 times over a period of 100 days without loss of activity. However, the activity declined in further reuses, leaving the preparation 50 and 35% active after its 60th and 70th uses, respectively. 相似文献
56.
57.
Milos Vucicevic Marija Stevanov‐Pavlovic Jevrosima Stevanovic Jasna Bosnjak Bojan Gajic Nevenka Aleksic Zoran Stanimirovic 《Zoo biology》2013,32(3):269-276
The aim of this research was to test the CHD gene (Chromo Helicase DNA‐binding gene) as a universal molecular marker for sexing birds of relatively distant species. The CHD gene corresponds to the aim because of its high degree of conservation and different lengths in Z and W chromosomes due to different intron sizes. DNA was isolated from feathers and the amplification of the CHD gene was performed with the following sets of polymerase chain reaction (PCR) primers: 2550F/2718R and P2/P8. Sex determination was attempted in 284 samples of 58 bird species. It was successful in 50 bird species; in 16 of those (Alopochen aegyptiacus, Ara severus, Aratinga acuticaudata, Bucorvus leadbeateri, Cereopsis novaehollandiae, Columba arquatrix, Corvus corax, C. frugilegus, Cyanoliseus patagonus, Guttera plumifera, Lamprotornis superbus, Milvus milvus, Neophron percnopterus, Ocyphaps lophotes, Podiceps cristatus, and Poicephalus senegalus), it was carried out for the first time using molecular markers and PCR. It is reasonable to assume that extensive research is necessary to define the CHD gene as a universal molecular marker for successful sex determination in all bird species (with exception of ratites). The results of this study may largely contribute to the aim. Zoo Biol 32:269–276, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
58.
Interspecies differences in DNA single strand breaks caused by benzo(a)pyrene and marine environment
The presence of DNA single strand breaks in untreated specimens of selected species, mosquito fish Gambusia affinis, painted comber Serranus scriba, blue mussel Mytilus galloprovincialis, spiny crab Maja crispata and sea cucumber Holothuria tubulosa as well as in 10 microg/g benzo(a)pyrene (BaP) treated mosquito fish, blue mussel and spiny crab was measured, using alkaline filter elution. Interspecies differences in alkaline elution profiles were observed and attributed to different lengths of DNA from different sources and to differences in the number of strand breaks present during normal cellular events in different phyla. Spiny crab hemocytes are more sensitive to action of BaP then blue mussel hemocytes and mosquito fish hepatocytes that could be explained by differences in the rates of distinct metabolic reactions and DNA repair among the investigated species. In field study, DNA single strand breaks were measured in hepatocytes of painted comber and in hemocytes of blue mussel and spiny crab from natural population specimens collected at eight sampling sites along Istrian coast, Croatia. Spatial variations in DNA integrity for each species were detected and revealed for the first time that spiny crab is responsive to different environmental conditions. Interspecies variations in the DNA integrity due to environmental conditions, confirmed species specific susceptibility to genotoxicity of certain environment that in long-term may modify the structure of marine communities. The multi-species approach in designing biomonitoring studies was suggested. 相似文献
59.
Uric acid may inhibit glucose-induced insulin secretion via binding to an essential arginine residue in rat pancreatic beta-cells 总被引:2,自引:0,他引:2
Rocić B Vucić-Lovrencić M Poje N Poje M Bertuzzi F 《Bioorganic & medicinal chemistry letters》2005,15(4):1181-1184
Uric acid (1a) suppresses basal insulin release in isolated rat pancreatic islets and inhibition of glucose-stimulated insulin secretion (GSIS) occurs right at hyperuricaemic levels (0.4 mM). Conversely, 1 mM guanidinium urate (2a) was completely ineffective, strongly suggesting that binding to an essential arginine residue triggers the inhibitory effect. A specific recognition of 1a molecule at the crucial beta-cell receptor is probably involved in the blocking glucose signal transduction. 相似文献
60.
Ramit Singla Kunj Bihari Gupta Shishir Upadhyay Monisha Dhiman Vikas Jaitak 《Bioorganic & medicinal chemistry》2018,26(1):266-277
Ground breaking clinical therapeutic advances in the treatment of breast cancer (BC) is the introduction of selective estrogen receptor modulators (SERMs). We have expeditiously designed and synthesized indole-xanthendione hybrids by coalescing the indole nucleus with xanthendione. All the compounds were first screened for anti-proliferative activity, cytotoxicity and ER-α binding affinity by utilizing ER-α dominant T47D BC cell lines, PBMCs and ER-α competitor assay kit. From this study, two representative compounds 6e and 6f showing most promising activity were advanced for gene expression studies for targeting ER-α. Cell imaging experiment undoubtedly indicate that both the compounds were able to cross cellular bio membrane and accumulate thus instigating cytotoxicity. RT-PCR and Western blotting experiments further strengthened that both compounds altered the expression of mRNA and receptor protein of ER-α, thereby forestalling downstream transactivation and signalling pathway in T47D cells line. Structural investigation from induced fit simulation study suggest that indole moiety of the compounds 6e and 6f helps in the anchoring of the xanthendione moiety in the hydrophobic region of the cavity thus enabling the compound to bind in antagonistic conformation similar to bazedoxifene by extensive hydrogen bonding and Van der Waals forces. All these finding collectively imply that compound 6e and 6f represents a novel potent ER-α antagonist and in the development of SERMs for the management of BC. 相似文献