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611.
We previously described the identification of the 3'end of an unknown gene CDK7 using differential display which appeared to be up-regulated in diabetic kidneys [R.A. Page, C.A. Morris, J.D. Williams, C.J. von Ruhland, A.N. Malik, Isolation of diabetes-associated kidney genes using differential display, Biochem. Biophys. Res. Commun. 232 (1997) 49-53]. Here we show that CDK7 is a putative thiol related gene which is regulated by glucose in human and rat renal cells. CDK7 mRNA increased by >threefold in cultured human mesangial cells grown in high glucose for 4 days. In the kidneys of the GK rat, a model of type II diabetes, CDK7 showed a steady age-related increase in mRNA, increasing to >sixfold in 40 week GK rats compared to normoglycemic age-matched Wistar rat kidneys, this increase correlates with progressive hyperglycemia. CDK7 mRNA is widely expressed, showing particularly high levels of expression in rat and human liver, and encodes a putative 338 amino acids highly conserved peptide with several conserved domains, including a cys-pro-arg-cys domain conserved in 15 diverse species which is similar to the catalytic centre of thioredoxin, suggesting a role in oxidative stress.  相似文献   
612.
Identifying how biological parameters change with age can provide insights into the physiological determinants of disease, and ultimately, death. Most prior studies of age-related change in biomarkers are based on cross-sectional data, small or selective samples, or a limited number of biomarkers. We use data from a nationally-representative longitudinal sample of 639 Taiwanese aged 54 and older in 2000 to assess changes over a six-year period in a wide range of biomarkers. Markers that increased most with age were glycoslyated hemoglobin, interleukin-6, and norepinephrine. Markers that decreased most with age were diastolic blood pressure and creatinine clearance. For example, glycoslyated hemoglobin increased by 8-13%, on average, over this six-year period. Several standard clinical risk factors exhibited little evidence of age-related change. Further research is needed to determine whether the observed variation between individuals in biomarker changes represents differences in underlying physiological function that are predictive of future health and survival.  相似文献   
613.
The tumor-associated glycoprotein (TAG)-72 is expressed in the majority of human adenocarcinomas but is rarely expressed in most normal tissues, which makes it a potential target for the diagnosis and therapy of a variety of human cancers. Here we describe the construction, affinity maturation, and biological characterization of an anti-TAG-72 humanized antibody with minimum potential immunogenicity. The humanized antibody was constructed by grafting only the specificity-determining residues (SDRs) within the complementarity-determining regions (CDRs) onto homologous human immunoglobulin germ line segments while retaining two mouse heavy chain framework residues that support the conformation of the CDRs. The resulting humanized antibody (AKA) showed only about 2-fold lower affinity compared with the original murine monoclonal antibody CC49 and 27-fold lower reactivity to patient serum compared with the humanized antibody HuCC49 that was constructed by CDR grafting. The affinity of AKA was improved by random mutagenesis of the heavy chain CDR3 (HCDR3). The highest affinity variant (3E8) showed 22-fold higher affinity compared with AKA and retained the original epitope specificity. Mutational analysis of the HCDR3 residues revealed that the replacement of Asn(97) by isoleucine or valine was critical for the affinity maturation. The 3E8 labeled with (125)I or (131)I showed efficient tumor targeting or therapeutic effects, respectively, in athymic mice with human colon carcinoma xenografts, suggesting that 3E8 may be beneficial for the diagnosis and therapy of tumors expressing TAG-72.  相似文献   
614.
A novel series of thiophene derived Schiff bases and their transition metal- [Co(II), Cu(II), Zn(II), Ni(II)] based compounds are reported. The Schiff bases act as tridentate ligands toward metal ions via azomethine-N, deprotonated-N of ammine substituents and S-atom of thienyl moiety. The synthesized ligands along with their metal complexes were screened for their in vitro antibacterial activity against six bacterial pathogens (Escherichia coli, Shigella flexneri, Pseudomonas aeruginosa, Salmonella typhi, Staphylococcus aureus and Bacillus subtilis) and for antifungal activity against six fungal pathogens (Trichophytonlongifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glabrata). The results of antimicrobial studies revealed the free ligands to possess potential activity which significantly increased upon chelation.  相似文献   
615.
Enhanced yield of tomato has ever been an important issue due to its nutritional value and various dietary consumption forms. But, efficient yield increase can never be achieved without using environmentally safe means e.g. innate resistance. In present study, tomato innate antifungal resistance has been boosted up using Penicillium oxalicum, and then various aspects of resistance modulation have been explored in details. Two tomato varieties of differential antifungal resistance (Dinaar and Red Tara) were treated with six P. oxalicum strains which screened the best inducer strain (Pn 5); which remarkably controlled disease incidence (DI) of Alternaria alternata. Inducer was not only responsible for almost two times production of phenolics, alkaloids and terpenoids in Red Tara, but it also non-significantly triggered same biochemicals in Dinaar. Hemicellulose showed only 40 % increase in variety of least antifungal resistance. During quantification assays of peroxidase (POD), phenyl ammonia lyase and polyphenol oxidase, more or less the same doubling trend was recorded in susceptible variety, while only POD had significant enhancement in resistant variety under the influence of fungal inducer. It was also recorded that inducer not only modulated quantity of enzyme (glucanase), but its isozyme package was also altered. Colorimetric quantifications of lignin, cellulose and pectins proved that biotic inducer strengthened the physical structure of plant cells by increasing these contents from 30 to 120 %. The above investigation collectively comes with the recommendation of an efficient and environmentally safe inducer (P. oxalicum); which, can be used to control fungal pathogens.  相似文献   
616.
Glutaredoxins (Grxs) are short, cysteine-rich glutathione (GSH)-mediated oxidoreductases. In this study, a chickpea (Cicer arietinum L.) glutaredoxin [LOC101493651 (CaGrx)] gene has been selected based on screening experiments with two contrasting varieties of chickpea, PUSA-362 (drought-tolerant) and ICC-1882 (drought-sensitive) under drought and salinity. The tolerant variety showed higher CaGrx gene expression, as compared to less in the sensitive variety, under both the stresses. The CaGrx gene was then over-expressed in Arabidopsis thaliana and were exposed to drought and salinity. The over-expression of CaGrx elevated the activity of glutaredoxin, which induced antioxidant enzymes (glutathione reductase; GR, glutathione peroxidase; GPX, catalase; CAT, ascorbate peroxidase; APX, glutathione-S-transferase; GST, superoxide dismutase; SOD, monodehydroascorbate reductase; MDHAR, and dehydroascorbate reductase; DHAR), antioxidants (GSH and ascorbate) and stress-responsive amino acids (cysteine and proline). Enhancement in the antioxidant defense system possibly administered tolerance in transgenics against both stresses. CaGrx reduced stress markers (H2O2, TBARS, and electrolyte leakage) and enhanced root growth, seed germination, and survival against both stresses. The physiological parameters (net photosynthesis; PN, water use efficiency; WUE, stomatal conductance; gs, transpiration; E, electron transport rate; ETR, and photochemical quenching; qP), chlorophylls and carotenoids, were improved in the transgenics during both stresses, that maintained the photosynthetic apparatus and protected the plants from damage. The enhanced activity of the cysteine biosynthesis enzyme, o-acetylserine (thiol) lyase (OAS-TL), increased the cysteine level in the transgenics, which elevated glutathione biosynthesis to maintain the ascorbate–glutathione cycle under both stresses. This investigation verified that the CaGrx gene provides tolerance against salinity and drought, maintaining physiological and morphological performances, and could be exploited for genetic engineering approaches to overcome both the stresses in various crops.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-00999-z.  相似文献   
617.
618.
The lipophilic vitamin E, α-Tocopherol (α-Toc), has been considered as a potent cellular antioxidant naturally occurring in biological membranes. It plays a number of key metabolic roles in plants exposed to various stressful cues. A field experimental was conducted on mungbean [Vigna radiata (L.) Wilczek] under varying water-limited regimes and the plants were sprayed with four levels of α-Toc (0, 100, 200, and 300 mg L?1) at the vegetative stage of plant growth. The results showed that limited field irrigation regimes (desiccated conditions) caused a marked reduction in growth parameters (shoot and root fresh and dry weights; shoot and root lengths), photosynthetic pigments (chlorophyll a and b), total soluble proteins (TSP) and yield attributes (number of pods, seeds per plant, weight of ripened pods and 100-seeds weight), while, in contrast, water deficiency induced an increase in phenolics, proline, glycine betaine (GB), hydrogen peroxide (H2O2), malondialdehyde (MDA), reducing and non-reducing sugars, total free amino acids, endogenous tocopherol levels, and activities of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). However, the foliar spray of α-Toc significantly improved shoot and root fresh and dry weights, shoot and root lengths, chlorophyll a and b contents, phenolics, proline, GB, reducing and non-reducing sugars, TSP, total free amino acids, endogenous tocopherol level, and activities of antioxidant enzymes (SOD, POD, and CAT), as well as yield parameters. On the other hand, it significantly decreased the MDA and H2O2 levels. Of all varying levels of α-Toc used, 100 mg L?1 was most effective in causing enhanced accumulation of ascorbic acid (AsA), MDA, and cellular tocopherols particularly in cv. Cyclone 7008, while proline and catalase in cv. Cyclone 8009. Of both cultivars, Cyclone 7008 was superior to the other cultivar in proline, TSP, SOD, and POD enzymes, but cv. Cyclone 8009 being superior in shoot fresh weights, root fresh weight, shoot and root lengths, chlorophyll a and b, phenolics, H2O2, AsA, MDA, CAT, number of pods, seeds, weight of ripened pods, and weight of 100 seeds under dry land conditions. Overall, exogenously applied tocopherol improved yield and myriad of key physio-biochemical attribute in mungbean.  相似文献   
619.
One of the problematic issues in soil pollution studies is heavy metal particles which are produced by mines and smelting units and spread through wind action and/or runoff. Pollution and health risk assessment of cadmium, lead, zinc, copper, and nickel in soil around the lead and zinc smelting factory was carried out in Zanjan City, Iran. Contamination factor (Cf), pollution load index (PLI), geoaccumulation index (Igeo), hazard quotient (HQ), hazard index (HI), and carcinogenic risk were pollution and human health risk assessment metrics in this study. Based on the Iranian soil guideline value, soil samples in the studied areas were contaminated the least by copper and nickel and the most by cadmium. PLI results showed that soils near the production line were heavily or extremely heavily polluted. The results of Cf and Igeo showed that lead and zinc were the most important contaminants. Health risk assessment indicated that lead and cadmium in soil were the main contaminants, which pose both carcinogenic and non-carcinogenic risks to human health; carcinogenic risk levels were unacceptably high (above 1 × 10?4). It can be concluded that mining and smelting activities degrade soil quality in this region and the soil pollution might be extended to farming areas.  相似文献   
620.
Recovery from CL is usually accompanied with long-lasting protection and induction of strong immune response. The phenotypes, generation and maintenance of central (=TCM) and effector (=TEM) memory T cell subsets in human leishmaniasis are not well known. Profile of T cell subsets were analyzed on peripheral CD8+ T cells from volunteers with history of cutaneous leishmaniasis (HCL).In HCL and control groups, mean frequencies of CCR7+CD45RA+CD8+ naïve and CCR7?CD45RA?CD8+ TEM cells were higher than other subsets before culture, but after stimulation with soluble Leishmania antigen, the frequency of naïve T cells was significantly decreased and the frequency of TEM cells was significantly increased. TEM phenotype composed the highest portion of proliferating Carboxy Fluorescein diacetate Succinimidyl Ester (CFSE)-dim population which was significantly higher in HCL volunteers than in control group. Stimulation of isolated CD8+ memory T cells, but not naïve T cells, from HCL volunteers induced a significantly higher IFN-γ production compared with that of healthy controls. Intracellular IFN-γ staining provided the same result.Memory population is shown to be responsible for Leishmania-induced IFN-γ production. Leishmania-reactive proliferating TEM cells were identified as the most frequent subset which may play a role in recall immune response and protection against Leishmania infection.  相似文献   
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