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61.
Crouse JR 《Current opinion in lipidology》1999,10(6):535-541
The results of recent trials indicate that statin treatment reduces not only the risk of coronary heart disease, but also the risk of stroke, in patients with existing heart disease. The need for the treatment of such patients is now generally recognized. Mechanisms for risk reduction include the retardation of plaque progression, plaque stabilization, and reducing the risk of coronary events. Questions remain regarding the discrepancy between epidemiological data and statin trials data, the precise mechanism of action of statins, and their role in the prevention of recurrent stroke in individuals who have experienced a previous stroke or transient ischemic attack but are free of coronary disease. 相似文献
62.
63.
Alex?SF?Doney Bettina?Fischer Joanne?E?Cecil Patricia?TW?Cohen Douglas?I?Boyle Graham?Leese Andrew?D?Morris Colin?NA?PalmerEmail author 《BMC genetics》2003,4(1):11
Background
The ARE insertion/deletion polymorphism of PPP1R3A has been associated with variation in glycaemic parameters and prevalence of diabetes. We have investigated its role in age of diagnosis, body weight and glycaemic control in 1,950 individuals with type 2 diabetes in Tayside, Scotland, and compared the ARE2 allele frequencies with 1,014 local schoolchildren. 相似文献64.
The Saccharomyces cerevisiae homologs of the bacterial mismatch repair proteins MutS and MutL correct replication errors and prevent recombination between homeologous (nonidentical) sequences. Previously, we demonstrated that Msh2p, Msh3p, and Pms1p regulate recombination between 91% identical inverted repeats, and here use the same substrates to show that Mlh1p and Msh6p have important antirecombination roles. In addition, substrates containing defined types of mismatches (base-base mismatches; 1-, 4-, or 12-nt insertion/deletion loops; or 18-nt palindromes) were used to examine recognition of these mismatches in mitotic recombination intermediates. Msh2p was required for recognition of all types of mismatches, whereas Msh6p recognized only base-base mismatches and 1-nt insertion/deletion loops. Msh3p was involved in recognition of the palindrome and all loops, but also had an unexpected antirecombination role when the potential heteroduplex contained only base-base mismatches. In contrast to their similar antimutator roles, Pms1p consistently inhibited recombination to a lesser degree than did Msh2p. In addition to the yeast MutS and MutL homologs, the exonuclease Exo1p and the nucleotide excision repair proteins Rad1p and Rad10p were found to have roles in inhibiting recombination between mismatched substrates. 相似文献
65.
Crouse GF 《Methods (San Diego, Calif.)》2000,22(2):116-119
Analyzing mutation spectra is a very powerful method to determine the effects of various types of DNA damage and to understand the workings of various DNA repair pathways. However, compiling sequence-specific mutation spectra is laborious; even with modern sequencing technology, it is rare to obtain spectra with more than several hundred data points. Two assay systems are described for yeast, one for insertion/deletion mutations and one for base substitution mutations, that allow determination of specific mutations without the necessity of DNA sequencing. The assay for insertion/deletion mutations uses a variety of different simple repeats placed in frame with URA3 such that insertions or deletions lead to a selectable Ura(-) phenotype; essentially all such mutations are in the simple repeat sequence. The assay for base substitution mutations uses a series of six strains with different mutations in one essential codon of the CYC1 gene. Because only true reversions lead to a selectable phenotype, the bases mutated in any reversion event are known. The advantage of these assays is that they can quantitatively determine over several orders of magnitude the types of mutations that occur under a given set of conditions, without DNA sequencing. 相似文献
66.
Scott R. Abella Joseph E. Crouse W. Wallace Covington Judith D. Springer 《Restoration Ecology》2015,23(2):113-121
A major challenge to advancing the science and practice of ecological restoration is working across large landscapes containing diverse sites that may respond differently to restoration. We conducted a 5‐year restoration experiment, replicated across 9 sites spanning 3 soil parent material types within a 9,000‐ha Pinus ponderosa forest landscape. We evaluated plant community response to restoration Pinus thinning, grazing, and aqueous smoke application. We measured vegetation before (2003) and 3 (2006) and 5 (2008) years after treatment. Plant community responses of species richness, cover, and composition were diverse, ranging from increases, decreases, or no change depending on soil parent material, tree thinning, and presence or exclusion of grazing. Restoration outcomes were under hierarchical control: soil parent material constrained response to Pinus thinning, which in turn influenced grazing effects. On limestone‐derived soil, responses included no change in species richness but increased plant cover with Pinus thinning. Both plant richness and cover increased on benmorite soil after thinning, and cover generally increased more without grazing. On rocky, basalt soil, plant richness increased but cover did not after any treatment. Diversity of responses to restoration has implications for: (1) setting goals or monitoring indicators tailored to inherent soil capability; (2) identifying where grazing most affects restoration outcomes; and (3) forecasting responses to restoration across landscapes. Diverse responses to restoration along physiographic gradients such as soil parent material warrant consideration when developing restoration across degraded landscapes. 相似文献
67.
Extra Replications in the “DNA-puffs” ofSciara coprophila 总被引:7,自引:0,他引:7
Using the Zeiss UMSP-1, a spectrophotometric study was made of DNA increase in three DNA-puffs located on chromosome II ofSciara coprophila. Each puff showed excessive and disproportionate synthesis. During the course of study it became apparent that the DNA in at least one of the puffs (the most proximal) arises from a number of cytological subunits (bands). When the DNA in the entire puff was measured, only irregular synthesis was revealed. On the other hand, when DNA increase in one of the bands was measured, the absorbancy values formed a geometric series, indicating that the extra DNA arises by additional complete rounds of replication.I wish to acknowledge support by the National Science Foundation (Grant GB-4336), the Max Planck-Gesellschaft, and the U.S. Atomic Energy Commission (Contract No. AT-(40-1)-2690). I am indebted to ProfessorWolfgang Beermann and ProfessorHans Bauer for making possible my trip to Tübingen and for providing laboratory facilities. 相似文献
68.
Effects of training and a single session of exercise on lipids and apolipoproteins in hypercholesterolemic men 总被引:1,自引:0,他引:1
Crouse Stephen F.; O'Brien Barbara C.; Grandjean Peter W.; Lowe Robert C.; Rohack J. James; Green John S. 《Journal of applied physiology》1997,83(6):2019-2028
Crouse, Stephen F., Barbara C. O'Brien, Peter W. Grandjean,Robert C. Lowe, J. James Rohack, and John S. Green. Effects oftraining and a single session of exercise on lipids and apolipoproteins in hypercholesterolemic men. J. Appl.Physiol. 83(6): 2019-2028, 1997.To differentiatebetween transient (acute) and training (chronic) effects of exercise attwo different intensities on blood lipids and apolipoproteins (apo), 26 hypercholesterolemic men (cholesterol = 258 mg/dl, age = 47 yr, weight = 81.9 kg) trained three times per week for 24 wk, 350 kcal/session athigh (80% maximal O2 uptake,n = 12) or moderate (50% maximalO2 uptake, n = 14) intensity. Serum lipid andapolipoprotein (apo) concentrations (plasma volume adjusted) weremeasured before and immediately, 24, and 48 h after exercise on fourdifferent occasions corresponding to 0, 8, 16, and 24 wk of training.Data were analyzed using three-way repeated-measures multivariateanalysis of variance followed by analysis of variance and Duncan'sprocedures ( = 0.05). A transient 6% rise inlow-density-lipoprotein cholesterol measured before training at the24-h time point was no longer evident after training. Triglyceridesfell and total cholesterol, high-density-lipoprotein cholesterol(HDL-C), HDL3-C, apo A-I, and apoB rose 24-48 h after exercise regardless of training or intensity.Total cholesterol, HDL3-C, apoA-I, and apo B were lower andHDL2-C was higher after trainingthan before training. Thus exercise training and a single session ofexercise exert distinct and interactive effects on lipids andapolipoproteins. These results support the practice of training atleast every other day to obtain optimal exercise benefits. 相似文献
69.
Mismatch Correction Acts as a Barrier to Homeologous Recombination in Saccharomyces Cerevisiae 总被引:21,自引:3,他引:18
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A homeologous mitotic recombination assay was used to test the role of Saccharomyces cerevisiae mismatch repair genes PMS1, MSH2 and MSH3 on recombination fidelity. A homeologous gene pair consisting of S. cerevisiae SPT15 and its S. pombe homolog were present as a direct repeat on chromosome V, with the exogenous S. pombe sequences inserted either upstream or downstream of the endogenous S. cerevisiae gene. Each gene carried a different inactivating mutation, rendering the starting strain Spt15(-). Recombinants that regenerated SPT15 function were scored after nonselective growth of the cells. In strains wild type for mismatch repair, homeologous recombination was depressed 150- to 180-fold relative to homologous controls, indicating that recombination between diverged sequences is inhibited. In one orientation of the homeologous gene pair, msh2 or msh3 mutations resulted in 17- and 9.6-fold elevations in recombination and the msh2 msh3 double mutant exhibited an 43-fold increase, implying that each MSH gene can function independently in trans to prevent homeologous recombination. Homologous recombination was not significantly affected by the msh mutations. In the other orientation, only msh2 strains were elevated (12-fold) for homeologous recombination. A mutation in MSH3 did not affect the rate of recombination in this orientation. Surprisingly, a pms1 deletion mutant did not exhibit elevated homeologous recombination. 相似文献
70.
Edwin J. Crouse Mfika Mubumbila Bjarn M. Stummann Gerhard Bookjans Christine Michalowski Hans J. Bohnert Jacques-Henry Weil Knud W. Henningsen 《Plant molecular biology》1986,7(2):143-149
Summary Isolated chloroplasts from Pisum sativum were found to contain at least 32 tRNA species. Hybridization of in vitro labeled, identified, chloroplast tRNAs to Pisum chloroplast DNA fragments revealed the locations of the tRNA genes on the circular chloroplast genome. Comparison of this gene map to the maps of Vicia faba and Phaseolus vulgaris showed that the chloroplast genomes of Pisum and Phaseolus are otherwise more closely related than either genome is to the chloroplast genome of Vicia. Furthermore, the results suggest how possible recombination events could be involved in the evolution of these three closely related, but divergent, chloroplast genomes. 相似文献