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1.
A simple and efficient method for DNA extraction from grapevine cultivars andVitis species 总被引:3,自引:0,他引:3
Muhammad A. Lodhi Guang-Ning Ye Norman F. Weeden Bruce I. Reisch 《Plant Molecular Biology Reporter》1994,12(1):6-13
A quick, simple, and reliable method for the extraction of DNA from grapevine species, hybrids, andAmpelopsis brevipedunculata (Vitaceae) has been developed. This method, based on that of Doyle and Doyle (1990), is a CTBA-based extraction procedure
modified by the use of NaCl to remove polysaccharides and PVP to eliminate polyphenols during DNA purification. The method
has also been used successfully for extraction of total DNA from other fruit species such as apple (Malus domestica), apricot (Prunus armeniaca), cherry (Prunus avium), peach (Prunus persica), plum (Prunus domestica), and raspberry (Rubus idaeus). DNA yield from this procedure is high (up to 1 mg/g of leaf tissue). DNA is completely digestible with restriction endonucleases
and amplifiable in the polymerase chain reaction (PCR), indicating freedom from common contaminating compounds. 相似文献
2.
Virginia P. Roxas Jing Wang Sundus Lodhi Randy D. Allen 《Acta Physiologiae Plantarum》1997,19(4):591-594
Research in our laboratory has focused on the analysis of the functions of a variety of enzymes that are involved in the scavenging
of reactive oxygen intermediates (ROI) such as superoxide radicals (·O
2
−
) and hydrogen peroxide (H2O2). Recent work has been on transgenic plants that over-express glutathione S-transferases (GST) that also have glutathione
peroxidase activity. Transgenic tobacco plants that contain gene constructs that encode two different tobacco GST’s had elevated
levels of both GST and GPX activity. Analysis of mature vegetative transgenic tobacco plants that over-express GST/GPX failed
to show any increase in paraquat tolerance or protection from photooxidative stress. However, seeds of these GST/GPX-expressing
tobacco lines are capable of more rapid germination and seedling growth at low temperatures and at elevated salt concentrations.
Reduced levels of lipid peroxidation were noted in GST/GPX-expressing seedling compared to control seedlings under both stressful
and non-stressful conditions. In addition, GST/GPX-expressing seedlings significantly accumulated more oxidized glutathione
(GSSG) than control seedlings during stress. These characteristics clearly indicate that over-expression of GST/GPX in transgenic
seedlings can have substantial effects on their stress tolerance. Furthermore, it appears that this effect is due primarily
to the elevated levels of GPX activity. 相似文献
3.
Study Objectives
The majority of adolescent sleep research has utilized self-reported sleep duration and some have based information on a solitary question. Whilst some have claimed to have validated sleep survey data with objective actigraphy measures in adolescents, the statistical approach applied only demonstrates the strength of the association between subjective and objective sleep duration data and does not reflect if these different methods actually agree.Methods
Data were collected as part of the Midlands Adolescents Schools Sleep Education Study (MASSES). Adolescents (n=225) aged 11-13 years provided estimates for weekday, weekend and combined sleep duration based on self-reported survey data, a 7-day sleep diary, and wrist-worn actigraphy.Results
We assessed the strength of the relationship as well as agreement levels between subjective and objectively determined sleep duration (weekday, weekend and combined). Subjective diary sleep duration was significantly correlated with actigraphy estimates for weekday and weekend sleep duration r=0.30, p≤0.001 and r=0.31, p≤0.001 respectively. Pitman’s test demonstrated no significant difference in the variance between weekend sleep duration (r=0.09, p=0.16) and combined sleep duration (r=0.12, p=0.08) indicating acceptable agreement between actigraphy and sleep diary sleep duration only. Self-reported sleep duration estimates (weekday, weekend and combined) did not agree with actigraphy determined sleep duration.Conclusions
Sleep diaries are a cost-effective alternative to survey/questionnaire data. Self-reported measures of sleep duration in adolescents do not agree with actigraphy measures and should be avoided where possible. Previous adolescent sleep studies that have utilized self-reported survey data may not provide a complete representation of sleep on the outcome measure of interest. 相似文献4.
Vanadium plays an important role in biological systems and exhibits a variety of bioactivities. In an effort to uncover the chemistry and biochemistry of vanadium with nitrogen- and oxygen-containing ligands, we report herein the synthesis and spectroscopic characterization of vanadium(IV) complexes with hydrazide ligands. Substituents on these ligands exhibit systematic variations of electronic and steric factors. Elemental and spectral data indicate the presence of a dimeric unit with two vanadium(IV) ions coordinated with two hydrazide ligands along with two H(2)O molecules. The stability studies of these complexes over time in coordinating solvent, DMSO, indicates binding of the solvent molecules to give [V2O2L2(H2O)2(DMSO)2]2+ (L=hydrazide ligand) and then conversion of it to a monomeric intermediate species, [VOL(DMSO)3]1+. Hydrazide ligands are inactive against urease, whereas vanadium(IV) complexes of these ligands show significant inhibitory potential against this enzyme and are found to be non-competitive inhibitors. These complexes also show low phytotoxicity indicating their usefulness for soil ureases. Structure-activity relationship studies indicate that the steric and/or electronic effects that may change the geometry of the complexes play an important role in their inhibitory potential and phytotoxicity. 相似文献
5.
Lodhi IJ Clift RE Omann GM Sweeney JF McMahon KK Hinshaw DB 《Archives of biochemistry and biophysics》2001,387(1):66-77
The objective of this study was to understand factors responsible for apoptotic body formation and release during apoptosis. We have found that inhibition of mono-ADP ribosylation after ultraviolet (UV) light induction of apoptosis in HL-60 cells does not block caspase-3 activation, gelsolin cleavage, or endonucleolytic DNA fragmentation. However, the cytoskeletal features of apoptosis leading to apoptotic body formation and release were inhibited by meta-iodobenzylguanidine (MIBG) and novobiocin, potent inhibitors of arginine-specific mono-ADP-ribosyltransferases (mono-ADPRTs). Suppression of mono-ADP ribosylation as late as 120 min following UV irradiation blocked the depolymerization of actin and release of apoptotic bodies. This suggested that the cytoskeletal changes of apoptosis may be decoupled from the caspase cascade and that there may be a biochemical event either distal to or independent of caspase-3 that regulates apoptotic body formation. To test the hypothesis that ADP ribosylation of actin may occur with the induction of apoptosis, an in vivo assay of mono-ADPRT activity using an antibody against ADP-ribosylarginine was used. An approximately 64% increase in the ADP ribosylation of actin was observed at 2 h following exposure to UV light. When MIBG or novobiocin was present, the ADP ribosylation of actin was only 14-18% above the levels observed in control nonirradiated cells. The current study is the first to demonstrate a relationship between ADP-ribosylation of actin and the formation of apoptotic bodies. 相似文献
6.
Ahmed Waqas Nahal Raza Haneen Wajid Lodhi Zerwah Muhammad Mehak Jamal Abdul Rehman 《PloS one》2015,10(1)
Introduction
Pregnancy is generally viewed as a time of fulfillment and joy; however, for many women it can be a stressful event. In South Asia it is associated with cultural stigmas revolving around gender discrimination, abnormal births and genetic abnormalities.Methodology
This cross-sectional study was done at four teaching hospitals in Lahore from February, 2014 to June, 2014. A total of 500 pregnant women seen at hospital obstetrics and gynecology departments were interviewed with a questionnaire consisting of three sections: demographics, the Hospital Anxiety and Depression Scale (HADS) and the Social Provisions Scale (SPS). Pearson’s chi-squared test, bivariate correlations and multiple linear regression were used to analyze associations between the independent variables and scores on the HADS and SPS.Results
Mean age among the 500 respondents was 27.41 years (5.65). Anxiety levels in participants were categorized as normal (145 women, 29%), borderline (110, 22%) or anxious (245, 49%). Depression levels were categorized as normal (218 women, 43.6%), borderline (123, 24.6%) or depressed (159, 31.8%). Inferential analysis revealed that higher HADS scores were significantly associated with lower scores on the SPS, rural background, history of harassment, abortion, cesarean delivery and unplanned pregnancies (P < .05). Social support (SPS score) mediated the relationship between the total number of children, gender of previous children and HADS score. Women with more daughters were significantly more likely to score higher on the HADS and lower on the SPS, whereas higher numbers of sons were associated with the opposite trends in the scores (P < .05).Conclusion
Because of the predominantly patriarchal sociocultural context in Pakistan, the predictors of antenatal anxiety and depression may differ from those in developed countries. We therefore suggest that interventions designed and implemented to reduce antenatal anxiety and depression should take into account these unique factors. 相似文献7.
8.
Khan T Ahmad M Nisar M Ahmad M Lodhi MA Choudhary MI 《Journal of enzyme inhibition and medicinal chemistry》2005,20(3):245-249
The ethanolic extract derived from aerial parts of an indigenous medicinal plant Paeonia emodi was screened for enzyme inhibition activities against Urease (jack bean and Bacillus pasteurii) and alpha-Chymotrypsin. The extract was also investigated for its radical scavenging activity using DPPH assay. The crude extract was found to possess significant enzyme inhibition activities against jack bean (74%) and Bacillus pasteurii (80%) urease and a moderate activity (54%) against alpha-Chymotrypsin. The extract also displayed excellent (83%) radical scavenging activity. On the basis of these results, the crude extract was subsequently fractionated into n-hexane, chloroform, ethyl acetate, n-butanol and water fractions and tested independently for the aforesaid activities. Significant inhibitory activity against urease enzyme was observed for the ethyl acetate, n-butanol and water fractions while the n-hexane and chloroform fractions were devoid of any such activity. In the alpha-Chymotrypsin enzyme inhibition studies the activity was concentrated into the ethyl acetate fraction. All the fractions displayed potent radical scavenging activity. The crude extract and fractions thereof were also subjected to total phenolic content determination. A correlation between radical scavenging capacities of extracts and total phenolic content was observed in the majority of cases. 相似文献
9.
Ansari FL Umbreen S Hussain L Makhmoor T Nawaz SA Lodhi MA Khan SN Shaheen F Choudhary MI;Atta-ur-Rahman 《化学与生物多样性》2005,2(4):487-496
A series of 2,4-diaryl-2,3,4,5-tetrahydro- (36-40) and 2,4-diaryl-2,3-dihydro-1,5-benzothiazepines (25-35) have been synthesized from the corresponding chalcones 1-24. Both the benzothiazepines and chalcones were evaluated as DPPH free-radical scavengers and as inhibitors of cholinesterases, urease, and alpha-glucosidase. Compounds 2, 5, 6, 7, 10, 13, 18, 21, 36a, 37a, 37b, and 39a showed significant cholinesterase inhibiting activities. Among the 15 dihydro-1,5-benzothiazepines, 26, 32, and 35 exhibited significant radical-scavenging activities; and six tetrahydro-1,5-benzothiazepines (35, 36a, 36b, 37a, 37b, and 39a) were found to be inhibitors of AChE and BChE. Compounds 22, 25, 26, 33, 35, 36a, 37b, and 39a inhibited urease, and 25 and 27-31 were found to be potent inhibitors of alpha-glucosidase. 相似文献
10.