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21.
Seo EK Wani MC Wall ME Navarro H Mukherjee R Farnsworth NR Kinghorn AD 《Phytochemistry》2000,55(1):35-42
Five benzophenones, vismiaguianones A-E, and two benzocoumarins, vismiaguianins A and B were isolated from the CHCl3 extract of the roots of Vismia guianensis by bioassay-directed fractionation using the DNA strand-scission assay and KB cell line. Of the isolates obtained, vismiaguianone B exhibited DNA strand-scission activity, whereas vismiaguianones D and E and vismiaguianin A were found to be significantly cytotoxic. 相似文献
22.
23.
Mohammad Isfaqul Hussain S. A. Wani K. Nagamani I. Fayaz M. A. Mir A. Nabi K. Qureshi M. A. Khan Y. Nishikawa 《World journal of microbiology & biotechnology》2010,26(10):1883-1889
Seven hundred and thirty-five diarrhoeic faecal samples from children were investigated for presence of enteroaggregative
E. coli (EAEC), enterotoxigenic E. coli (ETEC), diffusely adherent E. coli (DAEC) and Salmonella spp. by polymerase chain reaction (PCR) and bacterial culture. Out of 675 samples from Kashmir, 55 isolates were obtained,
which carried at least one virulence gene studied. Out of the 55 isolates, 36 (65.45%) were EAEC, 18 (32.72%) were ETEC while
only one isolate (1.81%) was DAEC. All the EAEC isolates were found to be typical as they possessed aggR gene. Six (16.66%) EAEC isolates carried the astA gene. Out of the 18 ETEC isolates, 13 carried the elt gene alone, four possessed both the elt and est genes and the remaining one harboured the est gene alone. Five ETEC isolates also possessed astA gene. Nineteen EAEC isolates belonged to 10 different serogroups. Serogroup O153 was most frequent. The ETEC isolates also
belonged to 10 different serogroups of which O159 was most predominant. Out of 224 E. coli isolates from 60 samples of Secunderabad, 27 isolates carried at least one virulence gene. Out of 27 isolates 22 (81.48%)
were typical EAEC, three (11.11%) were ETEC and two (7.4%) were DAEC. Fifteen EAEC isolates belonged to seven different serogroups
with O86 as most frequent. Four EAEC isolates also possessed the astA gene. All the three ETEC isolates harboured elt gene only and belonged to three different serogroups. Two isolates of Salmonella Worthington were obtained from only two samples in Kashmir. 相似文献
24.
Tanveer Ahmad Wani Abdus Samad Monika Tandon Gurpreet S. Saini P. L. Sharma K. K. Pillai 《AAPS PharmSciTech》2010,11(1):425-432
In this open-label, balanced, randomized, placebo-controlled, parallel study, healthy male volunteers were randomly divided
into two groups. Each group received either a single oral dose of rosuvastatin 20 mg or placebo. Estimations were done at
predose on day 1 of dosing (baseline) and 24 h postdose after days 7 and 14. Serum cortisol and serum lipid levels were estimated
using enzyme-linked immunosorbent assay kits and serum mevalonic acid (MVA) levels were measured using validated liquid chromatography–tandem
mass spectrometry method. Rosuvastatin produced a statistically significant (P < 0.05) decrease in total cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and
triglycerides. However, the increase in high-density lipoprotein cholesterol and decrease in cortisol and MVA were not statistically
significant when compared to the placebo-treated group. The study showed that rosuvastatin at a dose of 20 mg/day for a period
of 14 days was very potent as cholesterol-lowering agent, without any significant change in serum cortisol level in the healthy
Indian male population. 相似文献
25.
The Cr(VI)-reducing bacterial strain MCMB-821 was isolated from the alkaline crater lake of Lonar and was identified as Burkholderia cepacia. MCMB-821 was resistant to 1,000-ppm Cr(VI) and reduced 98% of the 75 ppm Cr(VI) within 36 h at pH 9.0 in the presence of
2% salt and lactose as the electron donor. The chromate-reducing efficiency of MCMB-821 was comparable under both aerobic
as well as anaerobic conditions. Electron paramagnetic resonance spectroscopy data suggested that MCMB-821 reduced Cr(VI)
to Cr(III) via the formation of transient Cr(V) intermediate. The chromate-reducing ability of MCMB-821 was suppressed in
the presence of membrane inhibitors and enhanced in the presence of 2,4-dinitrophenol, suggesting the involvement of electron
transport chain in the Cr(VI) bioreduction.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
26.
Effect of thyroidectomy (Tx) and subsequent treatment with 3,5,3′-triiodo-l-thyronine (T3) or replacement therapy (TR) with T3 + l-thyroxine (T4) on the temperature kinetics properties of FoF1 adenosine triphosphatase (ATPase, ATP synthase, H+-translocating ATP synthase EC 3.6.3.14)
and succinate oxidase (SO) and on the lipid/phospholipid makeup of rat kidney mitochondria were examined. Tx lowered ATPase
activity, which T3 treatment restored. SO activity was unchanged in Tx but decreased further by T3 treatment. TR restored both activities. The energies of ATPase activation in the high and low temperature ranges (E
H and E
L) increased in the Tx and T3 animals with decrease in phase transition temperature (Tt). TR restored E
H and E
L but not Tt to euthyroid levels. E
H and E
L of SO decreased in Tx animals. T3 and TR restored E
H whereas E
L was restored only in the TR group; Tt increased in both groups. Total phospholipid and cholesterol contents decreased significantly in Tx and T3-treated animals. In Tx animals, sphingomyelin (SPM) and phosphatidylcholine (PC) components decreased, while phosphatidylserine
(PS) and diphosphatidylglycerol components increased. T3 and TR treatments caused decreases in SPM, phosphatidylinositol and PS. PC and phosphatidylethanolamine (PE) increased in the T3 group. TR resulted in increased lysophospolipids and PE. Changes in kinetic parameters of the two enzymes were differently correlated
with specific phospholipid components. Both T3 and TR regimens were unable to restore normal membrane structure-function relationships. 相似文献
27.
28.
Qianzheng Zhu Nidhi Sharma Jinshan He Gulzar Wani Altaf A Wani 《Cell cycle (Georgetown, Tex.)》2015,14(9):1413-1425
During DNA damage response (DDR), histone ubiquitination by RNF168 is a critical event, which orchestrates the recruitment of downstream DDR factors, e.g. BRCA1 and 53BP1. Here, we report USP7 deubiquitinase regulates the stability of RNF168. We showed that USP7 disruption impairs H2A and ultraviolet radiation (UVR)-induced γH2AX monoubiquitination, and decreases the levels of pBmi1, Bmi1, RNF168 and BRCA1. The effect of USP7 disruption was recapitulated by siRNA-mediated USP7 depletion. The USP7 disruption also compromises the formation of UVR-induced foci (UVRIF) and ionizing radiation-induced foci (IRIF) of monoubiquitinated H2A (uH2A) and polyubiquitinated H2AX/A, and subsequently affects UVRIF and IRIF of BRCA1 as well as the IRIF of 53BP1. USP7 was shown to physically bind RNF168 in vitro and in vivo. Overexpression of wild-type USP7, but not its interaction-defective mutant, prevents UVR-induced RNF168 degradation. The USP7 mutant is unable to cleave Ub-conjugates of RNF168 in vivo. Importantly, ectopic expression of RNF168, or both RNF8 and RNF168 together in USP7-disrupted cells, significantly rescue the formation of UVRIF and IRIF of polyubiquitinated H2A and BRCA1. Taken together, these findings reveal an important role of USP7 in regulating ubiquitin-dependent signaling via stabilization of RNF168. 相似文献
29.
A putative epoxide hydrolase-encoding gene was identified from the genome sequence of Cupriavidus metallidurans CH34. The gene was cloned and overexpressed in Escherichia coli with His(6)-tag at its N-terminus. The epoxide hydrolase (CMEH) was purified to near homogeneity and was found to be a homodimer, with subunit molecular weight of 36 kDa. The CMEH had broad substrate specificity as it could hydrolyze 13 epoxides, out of 15 substrates tested. CMEH had high specific activity with 1,2-epoxyoctane, 1,2-epoxyhexane, styrene oxide (SO) and was also found to be active with meso-epoxides. The enzyme had optimum pH and temperature of 7.5 and 37°C respectively, with racemic SO. Biotransformation of 80 mM SO with recombinant whole E. coli cells expressing CMEH led to 56% ee(P) of (R)-diol with 77.23% conversion in 30 min. The enzyme could hydrolyze (R)-SO, ~2-fold faster than (S)-SO, though it accepted both (R)- and (S)-SO with similar affinity as K(m)(R) and K(m)(S) of CMEH were 2.05±0.42 and 2.11±0.16 mM, respectively. However, the k(cat)(R) and k(cat)(S) for the two enantiomers of SO were 4.80 and 3.34 s(-1), respectively. The wide substrate spectrum exhibited by CMEH combined with the fast conversion rate makes it a robust biocatalyst for industrial use. Regioselectivity studies with enantiopure (R)- and (S)-SO revealed that with slightly altered regioselectivity, CMEH has a high potential to synthesize an enantiopure (R)-PED, through an enantioconvergent hydrolytic process. 相似文献