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1.
Ponnaboina Thirupathi Keun-Hyeung Lee 《Bioorganic & medicinal chemistry letters》2013,23(24):6811-6815
A fluorescent chemosensor, Py-His, based on histidine was easily synthesized in solid phase synthesis. Py-His displayed a highly sensitive ratiometric response to Zn(II) with potent binding affinity (Ka = 1.17 × 1013 M?2) in aqueous solutions. The detection limit of Py-His for Zn(II) was calculated as 80.8 nM. Moreover, Py-His distinguished Zn(II) and Hg(II) by different ratiometric response type; the chemosensor showed a more enhanced increase of excimer emission intensity to Zn(II) than Hg(II). Upon addition of Ag(I) and Cu(II), Py-His showed a turn-off response mainly due to the quenching effect of these metal ions. The binding stoichiometry (2:1 or 1:1) of Py-His to target metal ions played a critical role in the fluorescent response type (ratiometric and turn off response) to target metal ions. The role of imidazole group of Py-His for ratiometric detection of Zn(II) was proposed by pH titration experiments. 相似文献
2.
Ravi Ranjan Rakesh Kumar Singh Thirupathi Yasotha Manish Kumar Kuldeep Kumar Renu Singh Monzamul Houque Vijay Prakash Mourya Gyanendra Singh Mihir Sarkar Bikash Chandra Das Sadhan Bag 《In vitro cellular & developmental biology. Animal》2013,49(7):486-491
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
3.
Ravi Pandiselvam Venkatachalam Thirupathi Striramasarma Mohan Palanisamy Vennila Doraiswamy Uma Sultan Shahir Sugumar Anandakumar 《Journal of Applied Entomology》2019,143(4):451-459
Extending the storage life of legumes by protecting it from the Callosobruchus maculatus infestation is a major concern for the producers, processors and exporters. Legume processing industry requires “greener” alternatives to the conventional fumigants. Gaseous ozone has a great potential as an insect management strategy that is suited for this niche. Nevertheless, the efficacy of ozone against C. maculatus is yet unknown. A laboratory study was conducted to test the insecticidal effect of ozone in controlling the infestation of C. maculatus in green gram. We have determined the concentration of ozone exposure time–mortality relationship for all the stages of C. maculatus that were exposed to 500–1,500 ppmv ozone. The percentages of mortality for different stages of C. maculatus increased with the increase in ozone concentration and exposure time. It was documented that adult stage is least tolerant to ozone (500 ppmv for 274.40 min exposure required to kill 90%), whereas the most tolerant stage is pupa (500 ppmv for 1816.54 min is required to kill 90%). The results indicate that gaseous ozone is the attractive alternative to the synthetic fumigants. 相似文献
4.
Free radical production and lipid peroxidation are potentially important mediators in testicular physiology and toxicology. Polychlorinated biphenyls (PCBs) are global environmental contaminants that cause disruption of the endocrine system in human and animals. The present study was conducted to elucidate the protective role of vitamin C and E against Aroclor 1254-induced changes in Leydig cell steroidogenesis and antioxidant system. Adult male rats were dosed for 30 days with daily intraperitoneal (ip) injection of 2 mg/kg Aroclor or vehicle (corn oil). One group of rats was treated with vitamin C (100 mg/kg bw/day) while the other group was treated with vitamin E (50 mg/kg bw/day) orally, simultaneously with Aroclor 1254 for 30 days. One day after the last treatment, animals were euthanized and blood was collected for the assay of serum hormones such as luteinizing hormone (LH), thyroid stimulating hormone (TSH), prolactin (PRL), triiodothyronine (T3), thyroxine (T4), testosterone and estradiol. Testes were quickly removed and Leydig cells were isolated in aseptic condition. Purity of Leydig cells was determined by 3β-hydroxysteroid dehydrogenase (3β-HSD) staining method. Purified Leydig cells were used for quantification of cell surface LH receptors and steroidogenic enzymes such as cytochrome P450 side chain cleavage enzyme (P450scc), 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-hydroxysteroid dehydrogenase (17β- HSD). Leydig cellular enzymatic antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), γ-glutamyl transpeptidase (γ-GT), glutathione-S-transferase (GST) and non-enzymatic antioxidants such as vitamin C and E were assayed. Lipid peroxidation (LPO) and reactive oxygen species (ROS) were also estimated in Leydig cells. Aroclor 1254 treatment significantly reduced the serum LH, TSH, PRL, T3, T4, testosterone and estradiol. In addition to this, Leydig cell surface LH receptors, activities of the steroidogenic enzymes such as cytochrome P450scc, 3β-HSD, 17β-HSD, antioxidant enzymes SOD, CAT, GPX, GR, γ-GT, GST and non-enzymatic antioxidants such as vitamin C and E were significantly diminished whereas, LPO and ROS were markedly elevated. However, the simultaneous administration of vitamin C and E in Aroclor 1254 exposed rats resulted a significant restoration of all the above-mentioned parameters to the control level. These observations suggest that vitamin C and E have ameliorative role against adverse effects of PCB on Leydig cell steroidogenesis. 相似文献
5.
Thirupathi Karuppanapandian Pritam Bala Sinha Abdul Majeeth Kamarul Haniya Kumariah Mamoharan 《Journal of Plant Biology》2006,49(6):440-447
Chromium-induced antioxidative responses of ascorbate-glutathione cycle enzymes and metabolites in green gram(Vigna radiata L. Wilczek) leaves were investigated in both dose and time-dependent manners. Rapid uptake of Cr was observed immediately
after the start of treatment. Significant reduction was observed in leaf biomass under 300 μM Cr-treatment. Treatment with
300 μM Cr increases the content of hydrogen peroxide and Superoxide dismytase activity upto initial 96 h, and then gradually
declined to the basal level. Ascorbate peroxidase and guaiacol peroxidase activities were low in 300 μM Cr-treated leaves
during the first 96 h, but significantly increased therefore, suggesting that increased enzyme activities would be responsible
for the removal of H2O2. Catalase activities were always suppressed under Cr stress. Contents of reduced ascorbate and dehydroascorbate were significantly
decreased under 300 uM Cr-treatment. The reduced glutathione content decreased at early stages of Cr-treatment. However, it
was restored to the normal level as in controls thereafter. In contrast, the glutathione disulphide content showed a progressive
increase during the initial hours of Cr-treatment. The non-protein thiol content was shown to increase during the first several
hours, but it declines at later stages. The present results demonstrate that Cr-induced oxidative stress is an important component
of the plant’s reaction to toxic levels of Cr. 相似文献
6.
Kumariah Manoharan Thirupathi Karuppanapandian Pritam Bala Sinha Rajendra Prasad 《Journal of Plant Biology》2005,48(4):394-403
We investigated 2,4-D-induced leaf senescence in young mustard seedlings. A set of morphometric, biochemical and molecular
parameters were analyzed to characterize senescence markers. In accordance with earlier reports, chloroplast-membrane degradation
marked the early phase of leaf senescence based on the analysis of the galactolipid fraction. Degradation of grana occurred
earlier to that of the envelope, as revealed by the relative level of their specific galactolipids, namely, monogalactosyl
diglyceride and digalactosyl diglyceride. Phospholipids showed extensive degradation resulting in the accumulation of lyso-derivatives
of major phospholipids and phosphatidic acid (PA) in senescing leaves. Catalase activity was stimulated by 2,4-D and reflected
scavenging of reactive oxygen species. Nuclear DNA degradation, a previously known death signal that represented a point of
no return from progression of senescence, occurred late on the 4th day subsequent to 2,4-D supplementation. AgNO3, an inhibitor of ethylene biosynthesis, inhibited leaf senescence by ca. 54% based on PA content Involvement of 2,4-D, ethylene
and abscisic acid in leaf senescence is discussed in relation to hormonal interplay. 相似文献
7.
Vishnu Priya Padmanaban Pankaj Verma Srividhyalakshmi Venkatabaskaran Thirupathi Keppayan Dharani Gopal Ashok Kumar Sekar Kirubagaran Ramalingam 《World journal of microbiology & biotechnology》2017,33(2):27
Microbial-derived natural products from extreme niches such as deepsea are known to possess structural and functional novelty. With this background, the present study was designed to investigate the bioprospecting potential and systematics of a deep-sea derived piezotolerant bacterial strain NIOT-Ch-40, showing affiliation to the genus Streptomyces based on 16S RNA gene similarity. Preliminary screening for the presence of biosynthetic genes like polyketide synthase I, polyketide synthase II, non ribosomal peptide synthase, 3-amino-5-hydroxybenzoic acid synthase and spiroindimicin followed by antibacterial activity testing confirmed the presence of potent bioactivity. The secondary metabolites produced during fermentation in Streptomyces broth at 28?°C for 7 days were extracted with ethyl acetate. The extract exhibited a specific inhibitory activity against Gram-positive bacteria and was significantly effective (p?<?0.0001) against methicillin-resistant Staphylococcus aureus (MRSA). The minimum inhibitory concentration and minimum bactericidal concentration against MRSA was 1.5 µg/mL, which was statistically significant in comparison with erythromycin. A multifaceted analysis of the Streptomyces spp. was carried out to delineate the strain NIOT-Ch-40 at a higher resolution which includes morphological, biochemical and molecular studies. Piezotolerance studies and comparison of fatty acid profiles at high pressures revealed that it could be considered as one of the taxonomic markers, especially for the strains isolated from the deep sea environments. In conclusion, the observation of comparative studies with reference strains indicated towards the strain NIOT-Ch-40 as an indigenous marine piezotolerant Streptomyces sp. with a higher probability of obtaining novel bioactive metabolites. 相似文献
8.
An equal concentration (100 μM) of Cr(III)- and Cr(VI)-induced changes in activities of antioxidative enzymes and metabolites
of ascorbate-glutathione cycle was studied in 7-d-old black gram (Vigna mungo L Hepper cv. Co4) seedlings for 5-d after infliction
of Cr stress. Seeds were germinated and grown in the presence or absence of Cr under controlled environmental conditions.
Uptake and translocation of Cr rate was relatively higher during first 12 h of treatment with both speciation of Cr, Cr(III)-
and Cr(VI)-treated black gram roots retained 15 times more Cr than the shoots. Significantly increased lipid peroxidation
was observed in the form of accumulation of malondialdehyde (MDA) and production of hydrogen peroxide (H2O2) molecule and superoxide (O2 ) radical after 6 h of infliction with Cr(VI) and after 12 h in Cr(III)-treated black gram roots. Superoxide dismutase (SOD)
and ascorbate peroxidase (APX) activities were significantly increased under Cr(VI)-treatment after 12 and 6 h, respectively.
However, catalase (CAT) and monodehydroascorbate reductase (MDHAR) activities were not significantly increased under Cr(Ill)-treatment.
There was a steep increase of 2.71 μmol g-1 FW in ascorbic acid (AA) content was observed between 6 and 24 h of Cr(VI)-treatment. Oxidized glutathione (GSSG) content
was steadily increased through the course of Cr(III)- and Cr(VI)-treatments, where as reduced glutathione (GSH) level was
decreased after 24 h of treatment. GSH/GSSG ratio was rapidly decreased in treatment with Cr(III) than the Cr(VI). There was
significant increase of 99 nmol g-1 FW in non-protein thiol (NPT) content was recorded between 6 and 24 h of Cr(VI)-treatment. The present results showed differential
response to AA and H2O2 signaling by Cr(III) and Cr(VI), AA in combination with APX was more effective in mitigating oxidative stress as against
the role of GSH as an antioxidant. 相似文献
9.
Duraisamy Y Gaffney J Slevin M Smith CA Williamson K Ahmed N 《Molecular and cellular biochemistry》2003,246(1-2):143-153
Hyperglycaemia reduces proliferation of bovine aortic endothelial cells in vitro. A similar effect in vivo may contribute to long-term complications of diabetes such as impaired wound-healing and retinopathy.We report the effect of increased glucose concentrations, glycated basic fibroblast growth factor (FGF-2) and bovine serum albumin-derived advanced glycation endproducts (BSA-AGE) on the proliferation of bovine aortic endothelial cells.Glucose (30 and 50 mmol/l) had an antiproliferative effect on endothelial cells. This effect may be mediated through reduced mitogenic activity of FGF-2. The glycation of FGF-2 with 250 mmol/l glucose-6-phosphate led to reduced mitogenic activity compared to native FGF-2. BSA-AGE at concentrations of 10, 50 and 250 g/ml had an antiproliferative effect on cultured endothelial cells.Aminosalicylic acid at a concentration of 200 mol/l proved to be more effective than equimolar concentrations of aminoguanidine in protecting endothelial cells against the antiproliferative effects of both high (30 mmol/l) glucose and 50 g/ml BSA-AGE. FGF-2 glycated in the presence of 4 mmol/l aminosalicylic acid or aminoguanidine retained mitogenic activity compared to that glycated in their absence.Compounds like aminoguanidine and, in particular, aminosalicylic acid protect endothelial cells against glucose-mediated toxicity and may therefore have therapeutic potential. 相似文献
10.
Palaniappan Murugesan Thirupathi Muthusamy Karundevi Balasubramanian 《Free radical research》2013,47(11):1259-1272
Free radical production and lipid peroxidation are potentially important mediators in testicular physiology and toxicology. Polychlorinated biphenyls (PCBs) are global environmental contaminants that cause disruption of the endocrine system in human and animals. The present study was conducted to elucidate the protective role of vitamin C and E against Aroclor 1254-induced changes in Leydig cell steroidogenesis and antioxidant system. Adult male rats were dosed for 30 days with daily intraperitoneal (ip) injection of 2 mg/kg Aroclor or vehicle (corn oil). One group of rats was treated with vitamin C (100 mg/kg bw/day) while the other group was treated with vitamin E (50 mg/kg bw/day) orally, simultaneously with Aroclor 1254 for 30 days. One day after the last treatment, animals were euthanized and blood was collected for the assay of serum hormones such as luteinizing hormone (LH), thyroid stimulating hormone (TSH), prolactin (PRL), triiodothyronine (T3), thyroxine (T4), testosterone and estradiol. Testes were quickly removed and Leydig cells were isolated in aseptic condition. Purity of Leydig cells was determined by 3β-hydroxysteroid dehydrogenase (3β-HSD) staining method. Purified Leydig cells were used for quantification of cell surface LH receptors and steroidogenic enzymes such as cytochrome P450 side chain cleavage enzyme (P450scc), 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-hydroxysteroid dehydrogenase (17β- HSD). Leydig cellular enzymatic antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), γ-glutamyl transpeptidase (γ-GT), glutathione-S-transferase (GST) and non-enzymatic antioxidants such as vitamin C and E were assayed. Lipid peroxidation (LPO) and reactive oxygen species (ROS) were also estimated in Leydig cells. Aroclor 1254 treatment significantly reduced the serum LH, TSH, PRL, T3, T4, testosterone and estradiol. In addition to this, Leydig cell surface LH receptors, activities of the steroidogenic enzymes such as cytochrome P450scc, 3β-HSD, 17β-HSD, antioxidant enzymes SOD, CAT, GPX, GR, γ-GT, GST and non-enzymatic antioxidants such as vitamin C and E were significantly diminished whereas, LPO and ROS were markedly elevated. However, the simultaneous administration of vitamin C and E in Aroclor 1254 exposed rats resulted a significant restoration of all the above-mentioned parameters to the control level. These observations suggest that vitamin C and E have ameliorative role against adverse effects of PCB on Leydig cell steroidogenesis. 相似文献