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71.
Ravikumar YS Mahadevan KM Kumaraswamy MN Vaidya VP Manjunatha H Kumar V Satyanarayana ND 《Environmental toxicology and pharmacology》2008,26(2):142-146
Antioxidative potential of alcohol extract of Polyalthia cerasoides was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical, superoxide anion scavenging, and reducing power assays were performed. The extract showed significant reactive oxygen species (ROS) scavenging activity in all in vitro antioxidant assays and contained high level of total phenolic content. For in vivo genotoxic evaluation, Swiss albino mice were treated with alcohol extract at the concentration of 40mg/kg body weight. Frequency of aberration was compared with control. Both the sets did not showed genotoxic effect. Further the extract was subjected to cytotoxic study using 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphynyl tetrazolium bromide (MTT) assay, the extract confirmed to show moderate cytotoxicity against L929 cell line. 相似文献
72.
Mahadevan B Marston CP Dashwood WM Li Y Pereira C Baird WM 《Chemical research in toxicology》2005,18(2):224-231
A complex mixture of polycyclic aromatic hydrocarbons (PAH) extracted from coal tar, standard reference material (SRM) 1597, has been shown to initiate tumor formation in mouse initiation-promotion assays in our laboratory [(2001) Carcinogenesis 22 (7), 1077-1086]. To determine the effects of SRM 1597 on PAH activation in human cells, we investigated the PAH-DNA adduct formation in the human mammary carcinoma-derived cell line MCF-7. We examined the effects of SRM 1597 on the metabolic activation to DNA binding derivatives of two carcinogenic PAHs, the bay region containing benzo[a]pyrene (B[a]P) and the more carcinogenic fjord region containing dibenzo[a,l]pyrene (DB[a,l]P). PAH-DNA adduct analysis by 33P-postlabeling and reversed phase high-performance liquid chromatography revealed a significant decrease in the levels of both B[a]P and DB[a,l]P DNA adduct formation on cotreatment with SRM 1597 in comparison to cells exposed to B[a]P or DB[a,l]P alone. However, the inhibition of PAH-DNA adduct formation only occurred within the first 48 h of exposure in cells cotreated with SRM 1597 and B[a]P. In contrast, SRM 1597 significantly inhibited the level of DB[a,l]P DNA adducts throughout the 120 h of exposure. Induction of human cytochrome P450 (P450) enzymes 1A1 and P4501B1 on treatment with SRM 1597 was observed by immunoblots. These results suggest that the important factors in determining the carcinogenic activity of PAH within a complex mixture would depend on the ability of other components of the mixture to promote or inhibit the activation of carcinogenic PAH by the induction of P450 enzymes followed by the formation of DNA adducts. 相似文献
73.
Intentional infliximab use during pregnancy for induction or maintenance of remission in Crohn's disease 总被引:8,自引:0,他引:8
Mahadevan U Kane S Sandborn WJ Cohen RD Hanson K Terdiman JP Binion DG 《Alimentary pharmacology & therapeutics》2005,21(6):733-738
AIM: To study the effects of infliximab on pregnancy and foetal outcome. METHODS: We conducted a retrospective chart review of women with Crohn's disease treated intentionally with infliximab during pregnancy. The primary outcome measure was the occurrence of congenital malformations. Secondary outcome measures were the rate of premature birth, low-birth weight, small for gestational age infants, intrauterine growth retardation and caesarean section. RESULTS: Ten women were identified. Eight women received maintenance infliximab infusions throughout their pregnancy and two women received their initial infliximab infusions during pregnancy. All 10 pregnancies ended in live births. No infants had congenital malformations, intrauterine growth retardation or small for gestational age parameters. Three infants were premature and one had low-birth weight. Eight women had a caesarean section. CONCLUSIONS: This is the first reported series of intentional infliximab use throughout pregnancy. These data, combined with other studies of inadvertent use of infliximab during pregnancy, suggest that the benefits of infliximab in achieving response and maintaining remission in mothers with Crohn's disease may outweigh the risk to the foetus of exposure to the drug. Further prospective data collection will be helpful to confirm these findings. 相似文献
74.
Marson CM Savy P Rioja AS Mahadevan T Mikol C Veerupillai A Nsubuga E Chahwan A Joel SP 《Journal of medicinal chemistry》2006,49(2):800-805
The synthesis of a novel series of potent inhibitors of histone deacetylases is described, based on arylsulfinyl-2,4-hexadienoic acid hydroxyamides and their derivatives. In vitro IC(50) values down to 40 nM were obtained, and several compounds showed inhibition of CEM (human leukemic) cell viability with IC(50) of approximately 1.5 microM, comparable to or better than that of suberoylanilide hydroxamic acid, an inhibitor of histone deacetylase currently in clinical trials. 相似文献
75.
Follicular factors, serum estradiol, and outcome of pregnancy following in vitro fertilization and embryo transfer 总被引:2,自引:0,他引:2
D Lewinthal M Mahadevan H A Pattinson P J Taylor D Persaud 《Fertility and sterility》1987,48(5):840-842
Success rate of in vitro fertilization and embryo transfer (IVF-ET) depends upon clinical and laboratory variables. This study compared follicular measurements and serum estradiol (E2) between 23 delivered and 23 nonpregnant controls following IVF-ET. E2, number of large follicles (no.), E2/no. ratio, total diameter of large follicle (TD), and the E2/TD ratio were compared between the two groups and between 23 women who delivered and 10 who aborted. E2 (P = 0.03), E2/no. (P = 0.006), and E2/TD (P = 0.005) were found to differ significantly between delivered and controls and between delivered and those who aborted. 相似文献
76.
A rapid method for viability and drug sensitivity of Mycobacterium leprae cultured in macrophages and using fluorescein diacetate 总被引:1,自引:0,他引:1
The ability of viable M. leprae to hydrolyze Fluorescein diacetate and retain fluorescein inside the bacteria was used to identify viable M. leprae inside the cultured in vitro macrophages. The subjective microscopic count of the FDA test was demonstrated as useful routine test by confirming the results obtained therein with a quantitative and non subjective measurement of fluorescence in spectrofluorimeter. Using this method loss of viability of M. leprae in presence of dapsone and rifampicin was demonstrated. Such an assay, was well correlated with another in vitro assay, the Fc receptor test and also the in vivo mouse foot test. The drug resistance of clinical isolates of M. leprae demonstrated by mouse foot pad was also correlated with FDA test system. Thus we have reported a reliable, consistent and rapid in vitro test system for determining viability and drug sensitivity of M. leprae. 相似文献
77.
78.
79.
M. Mahadevan K. Chalder D. Wiseman A. Leader P. J. Taylor 《Journal of assisted reproduction and genetics》1987,4(5):277-280
Animal and human data would suggest that ultrasound causes deleterious effects to oocytes during meiosis. We directly compared the fertilization rate and embryonic development following in vitro fertilization and embryo transfer of those oocytes exposed to ultrasound and those not exposed in the same patient. In 39 unscreened patients a combination of laparoscopy and ultrasound was used for oocyte recovery. Laparoscopy was performed first on the most accessible ovary (usually the right) and at least one oocyte was obtained. Ultrasoundguided oocyte recovery was successful in the other inaccessible ovary. To assess how oocytes obtained by ultrasound or laparoscopy related to the pregnancy rate, two groups of patients were evaluated in whom the embryos transferred either had been exposed to ultrasound or had not been. The fertilization and the embryo cleavage rates were not significantly different between the ultrasoundexposed and the unexposed groups. The pregnancy rate was also not significantly different [9 of 49 (18.4%) for ultrasound exposed versus 14 of 74 (18.9%) for unexposed]. There was one early spontaneous abortion in each group. Further analysis of a group of 40 patients, in whom the oocytes were exposed to ultrasound in situ, after the endogenous luteinizing hormone (LH) surge had begun 1–27 hr earlier, revealed that 6 became pregnant (15%). This preliminary study suggests that exposure of human oocytes to ultrasonic waves, either during the different phases of meiosis or after the completion of meiosis, did not significantly influence the developmental potential of the in vitro fertilized embryos. 相似文献
80.