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101.
Anemia affects a substantial portion of the world’s population, provoking severe health problems as well as important economic losses to the region in which this condition is found. This study was designed to compare the levels of essential trace and toxic elements in scalp hair, blood, and urine samples of anemic children (n = 132) with age range 1–5 and 6–10 years of both genders. For a comparative study, 134 non-anemic age- and sex-matched children as control subjects, residing in the same city, were selected. The metals in the biological samples were measured by flame atomic absorption spectrophotometry/electrothermal atomic absorption spectrometry prior to microwave-assisted acid digestion. The proposed method was validated using certified reference samples of hair, blood, and urine. The results indicated significantly lower levels of iron, copper, and zinc in the biological samples as compared to the control children of both genders (p = 0.01–0.008). The mean values of lead and cadmium were significantly high in all three biological samples of anemic children as compared to non-anemic children of both age groups (p = 0.005–0.001). The ratios of essential metal to toxic metals in the biological samples of anemic children of both age groups were significantly lower than that of controls. Deficiency of essential trace metals and high level of toxic metals may play a role in the development of anemia in the subjects under study.  相似文献   
102.
This study was designed to compare the levels of chromium (Cr) and manganese (Mn) in scalp hair, blood, and urine of night blindness in children age ranged (3–7) and (8–12) years of both genders, comparing them to sex- and age-matched controls. A microwave-assisted wet acid digestion procedure, was developed as a sample pretreatment, for the determination of Cr and Mn in biological samples of night blindness children. The proposed method was validated by using conventional wet digestion and certified reference samples of hair, blood and urine. The digests of all biological samples were analyzed for Cr and Mn by electrothermal atomic absorption spectrometry. The results indicated significantly higher levels of Cr, whilst low level of Mn in the biological samples (blood and scalp hair) of male and female night blindness children, compared with control subjects of both genders. These data present guidance to clinicians and other professional investigating deficiency of Mn and excessive level of Cr in biological samples (scalp hair and blood) of night blindness children.  相似文献   
103.
The present study was conducted to see the in vivo developmental potency of caprine parthenogenetic embryos generated in a modified way. The good quality caprine oocytes were matured in presence of cytochalasin B (CCB) and then activated by 7% ethanol followed by 2 mM 6-dimethyl amino purine (6-DMAP) and embryo development was recorded. Early stage parthenogenetic embryos (two to four cells) were surgically transferred in recipients (10). The pregnancy diagnosis was done by nonreturn to oestrus, ultrasonography (USG), and progesterone estimation. The levels of progesterone were above normal values (1 ng/ml) of pregnancy and fall below the level of pregnancy just before retuned to oestrus. Progesterone profile revealed that out of ten recipients (G1–G10), four goats (G1, G2, G3, and G5) returned to oestrus after 43?±?7.29 (Mean?±?SE) d of embryo transfer and six goats (G4, G6, G7, G8, G9, and G10) did not return to cycle even after 70 d of embryo transfer. In three recipients (G4, G5, and G6), the USG on day 40 revealed that there was fluid filled uterine body with solid fetus-like structure. These might be dead fetus and had started resorption. The progesterone profile also corroborated the assumption of pregnancy in these animals. Authors believe that this may be the first report on in vivo diploid parthenogenetic embryo development in caprine species.  相似文献   
104.
The thiol–disulphide exchange regulates the activity of proteins by redox modulation. Many studies to analyze reactive oxygen species (ROS), particularly, hydrogen peroxide (H2O2) induced changes in the gene expression have been reported, but efforts to detect H2O2 modified proteins are comparatively few. Two-dimensional diagonal redox sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) was used to detect polypeptides which undergo thiol–disulphide exchange in Brassica juncea seedlings following H2O2 (10 mM) treatment for 30 min. Eleven redox responsive polypeptides were identified which included cruciferin, NLI [Nuclear LIM (Lin11, Isl-1 & Mec-3 domains)] interacting protein phosphatase, RuBisCO (ribulose-1,5-bisphosphate carboxylase/oxygenase) large subunit, and myrosinase. Redox modulation of RuBisCO large subunit was further confirmed by western blotting. However, the small subunit of RuBisCO was not affected by these redox changes. All redox modulated targets except NLI interacting protein (although it contains two cysteines) showed oxidation sensitive cysteines by in silico analysis. Interestingly, interactome of cruciferin and myrosinase indicated that they may have additional function(s) beside their well-known roles in the seedling development and abiotic stress respectively. Cruciferin showed interactions with stress associated proteins like defensing-like protein 192 and 2-cys peroxiredoxin. Similarly, myrosinase showed interactions with nitrilase and cytochrome p450 which are involved in nitrogen metabolism and/or hormone biosynthesis. This simple procedure can be used to detect major stress mediated redox changes in other plants.  相似文献   
105.
Polygonatum verticillatum (L.) All. is an important medicinal herb that belongs to the family Asparagaceae. The rhizome of the species is used in Chyavanprash preparation and several other ayurvedic formulations. Numerous active constituents like saponins, alkaloids, phytohormones, flavonoids, antioxidants, lysine, serine, aspartic acid, diosgenin, β-sitosterol, etc. have been reported from this species. In this study, morphological, phytochemical, antioxidant and genetic variations of 11 distant populations of P. verticillatum were measured. Considerably (P < 0.05) higher variations were recorded among different populations of P. verticillatum using morphological, phytochemical and genetic diversity parameters. AGFW (above ground fresh weights); flavonols, FRAP (Ferric ion reducing antioxidant power) and NO (Nitric Oxide scavenging activity) were recorded maximum in Kafni population. Similarly, a significantly higher above and below ground dry weight was recorded in Mayawati and Surmoli populations respectively. Maximum phenolic content, tannins, and DPPH (2,2-diphenyl-1-picrylhydrazyl) activity were recorded in Milam population. A total of 165 individuals from 11 populations were assessed for genetic diversity using inter-simple sequence repeats (ISSR) marker. High genetic diversity (He = 0.35) was recorded in Himkhola and Surmoli populations while it was observed minimum (0.28) in the Mayawati population. Altitude showed a significant positive correlation with tannins (r = 0.674; P < 005) and DPPH (r = 0.820; P < 0.01). Phenol content exhibited a considerably positive relationship with He (r = 0.606; P < 0.05) and BGFW (r = 0.620; P < 0.05), flavonol displayed a positive correlation with Pp% (r = 0.606; P < 0.05). The population structure of P. verticillatum, exhibited that the optimal value of the K was 3 for its populations as determined by the ΔK statistic structure. Among populations, the amount of gene flow is higher (Nm = 1.717) among all sites. Hence, it can be concluded that P. verticillatum populations possess considerable variability in the collected populations. Likewise, the populations from Kafni, Satbunga and Himkhola with higher morphological, phytochemicals and genetic variability were prioritized and therefore recommended for cultivation and mass multiplication to meet the industrial demand for target species.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-01044-9.  相似文献   
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108.
In normotensive rabbits topical application of Daucus carota seed extract at the concentration of 0.3, 0.6 and 1.2% resulted in mean IOP reduction of 19.33. 23.20 and 25.61% respectively from baseline. As no significant difference was observed between the change in IOP in 0.6 and 1.2% extract treated groups, 0.6% concentration was chosen for further evaluation in rabbits with experimentally elevated IOP. In water loaded rabbits, maximum mean IOP reduction with 0.6% extract was 29.39%, which was comparable to pilocarpine. In steroid pretreated rabbits, maximum mean IOP reduction was 30.27% from baseline, which was significantly higher than pilocarpine. The extract showed a comparatively slower onset of action however, the duration of action was comparable to pilocarpine in all the experimental models.  相似文献   
109.
Tuteja N  Ahmad P  Panda BB  Tuteja R 《Mutation research》2009,681(2-3):134-149
Plant cells are constantly exposed to environmental agents and endogenous processes that inflict damage to DNA and cause genotoxic stress, which can reduce plant genome stability, growth and productivity. Plants are most affected by solar UV-B radiation, which damage the DNA by inducing the formation of two main UV photoproducts such as cyclobutane pyrimidine dimers (CPDs) and pyrimidine (6-4) pyrimidone photoproducts (6-4PPs). Reactive oxygen species (ROS) are also generated extra- or intra-cellularly, which constitute yet another source of genotoxic stress. As a result of this stress, the cellular DNA-damage responses (DDR) are activated, which transiently arrest the cell cycle and allow cells to repair DNA before proceeding into mitosis. DDR requires the activation of Ataxia telangiectasia-mutated (ATM) and Rad3-related (ATR) genes, which regulate the cell cycle and transmit the damage signals to downstream effectors of cell-cycle progression. Since genomic protection and stability are fundamental to ensure and sustain plant diversity and productivity, therefore, repair of DNA damages is essential. In plants the bulky DNA lesions, CPDs and 6-4PPs, are repaired by a simple and error-free mechanism: photoreactivation, which is a light-dependent mechanism and requires CPD or 6-4PP specific photolyases. In addition to this direct repair process, the plants also have sophisticated light-independent general repair mechanisms, such as the nucleotide excision repair (NER) and base excision repair (BER). The completed plant genome sequences reveal that most of the genes involved in NER and BER are present in higher plants, which suggests that the network of in-built DNA-damage repair mechanisms is conserved. This article describes the insight underlying the DNA damage and repair pathways in plants. The comet assay to measure the DNA damage and the role of DNA repair helicases such as XPD and XPB are also covered.  相似文献   
110.
Members of all four families of ectonucleotidases, namely ectonucleoside triphosphate diphosphohydrolases (NTPDases), ectonucleotide pyrophosphatase/phosphodiesterases (NPPs), ecto-5′-nucleotidase and alkaline phosphatases, have been identified in the renal vasculature and/or tubular structures. In rats and mice, NTPDase1, which hydrolyses ATP through to AMP, is prominent throughout most of the renal vasculature and is also present in the thin ascending limb of Henle and medullary collecting duct. NTPDase2 and NTPDase3, which both prefer ATP over ADP as a substrate, are found in most nephron segments beyond the proximal tubule. NPPs catalyse not only the hydrolysis of ATP and ADP, but also of diadenosine polyphosphates. NPP1 has been identified in proximal and distal tubules of the mouse, while NPP3 is expressed in the rat glomerulus and pars recta, but not in more distal segments. Ecto-5′-nucleotidase, which catalyses the conversion of AMP to adenosine, is found in apical membranes of rat proximal convoluted tubule and intercalated cells of the distal nephron, as well as in the peritubular space. Finally, an alkaline phosphatase, which can theoretically catalyse the entire hydrolysis chain from nucleoside triphosphate to nucleoside, has been identified in apical membranes of rat proximal tubules; however, this enzyme exhibits relatively high K m values for adenine nucleotides. Although information on renal ectonucleotidases is still incomplete, the enzymes’ varied distribution in the vasculature and along the nephron suggests that they can profoundly influence purinoceptor activity through the hydrolysis, and generation, of agonists of the various purinoceptor subtypes. This review provides an update on renal ectonucleotidases and speculates on the functional significance of these enzymes in terms of glomerular and tubular physiology and pathophysiology.  相似文献   
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