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101.
A simple method for N-15 labelling of exocyclic amino groups in synthetic oligodeoxynucleotides 下载免费PDF全文
Montse Acedo Carme Fbrega Anna Avio Myron Goodman Patricia Fagan David Wemmer Ramon Eritja 《Nucleic acids research》1994,22(15):2982-2989
The use of the ammonia deprotection step to introduce 15N labels at specific exocyclic amino positions of adenine, cytosine, guanine or 2-aminopurine of oligodeoxynucleotides is described. 相似文献
102.
Grace L. Jung Paul C. Anderson Murray Bailey Monique Baillet Gary W. Bantle Sylvie Berthiaume Pierre Lavallée Montse Llinas-Brunet Bounkham Thavonekham Diane Thibeault Bruno Simoneau 《Bioorganic & medicinal chemistry》1998,6(12):2317-2336
Renin inhibitors containing a 4,5- or a 3,5-dihydroxy-2-substituted-6-phenylhexanamide fragment at the P2---P3 sites have been prepared and evaluated. The four possible diastereomeric diols of the two series of inhibitors were synthesized to determine the optimal configuration of the carbinol centers for these replacements. The most potent inhibitors of each series, 1a and 2c have a molecular weight of only 503 and IC50 values of 23 and 20 nM in a human plasma renin assay at pH 6.0. Their very low aqueous solubility limited their further evaluation. The efficacy of these P2---P3 replacements is a result of their ability to maintain the important hydrogen-bonds with the enzyme. Due to conformational differences with the dipeptide, adjustment at the P2 side chain was required. These 4,5- and 3,5-dihydroxyhexanamide segments could be seen as novel N-terminal dipeptide replacements. 相似文献
103.
A novel branch of the Ras family, Rit, was recently identified. Rit exhibits a distinct C-terminus and effector domain, and does not activate mitogen-activated protein kinase (MAPK) but can cooperate with Raf to transform fibroblasts. Here, we found that when overexpressed, activated mutants of Rit transform NIH 3T3 cells efficiently, and stimulate p38gamma but not MAPK, p38alpha, p38gamma, p38delta, or ERK5. Furthermore, we provide evidence that p38gamma activation is required for the ability of Rit to stimulate gene expression and cellular transformation. These findings suggest that this unique GTPase stimulates proliferative pathways distinct from those regulated by other Ras family members. 相似文献
104.
Alvarez M Sedano S Cuadrado G Redondo JC 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(4):1110-1121
The purpose of this study was to determine the effects of an 18-week strength training program on variables related to low-handicap golfers' performance. Ten right-handed male golfers, reporting a handicap of 5 or less, were randomly divided into two groups: the control group (CG) (N = 5, age: 23.9 ± 6.7 years) and the treatment group (TG) (N = 5, age: 24.2 ± 5.4 years). CG players followed the standard physical conditioning program for golf, which was partially modified for the TG. The TG participated in an 18-week strength training program divided into three parts: maximal strength training including weightlifting exercises (2 days a week for 6 weeks), explosive strength training with combined weights and plyometric exercises (2 days a week for 6 weeks), and golf-specific strength training, including swings with a weighted club and accelerated swings with an acceleration tubing system (3 days a week for 6 weeks). Body mass, body fat, muscle mass, jumping ability, isometric grip strength, maximal strength (RM), ball speed, and golf club mean acceleration were measured on five separate occasions. The TG demonstrated significant increases (p < 0.05) in maximal and explosive strength after 6 weeks of training and in driving performance after 12 weeks. These improvements remained unaltered during the 6-week golf-specific training period and even during a 5-week detraining period. It may be concluded that an 18-week strength training program can improve maximal and explosive strength and these increases can be transferred to driving performance; however, golfers need time to transfer the gains. 相似文献
105.
Mariana Cerda-Esteve Agustín Ruiz-González Mindaugas Gudelis Albert Goday Javier Trujillano Elisa Cuadrado Juan Francisco Cano 《Endocrinología y nutrición》2010,57(5):182-186
IntroductionHyponatremia is considered the most frequent electrolyte disorder found in hospitalized patients and seems to be a prognostic factor during hospitalization.MethodsA prospective observational study was carried out in consecutive neurological patients admitted to our hospital over a 3-month period. Blood and urinary ionogram and osmolality were determined at entry and 3–5 days after admission in all patients with hyponatremia.ResultsOf the 130 patients admitted, 19 (14.6%) had hyponatremia. The causes of hyponatremia were as follows: inappropriate fluid replacement in 4 patients (21%), antihypertensive drugs in 4 (21%), syndrome of inappropriate secretion of antidiuretic hormone in 4 (21%), cerebral salt wasting syndrome in 2 (10%), and edematous status caused by liver disease in one and digestive loss in one (5%) each. Mortality was one (5%) and 0 (0%) among patients with and without hyponatremia, respectively.ConclusionHyponatremia is common in hospitalized neurological patients and can be misdiagnosed as a worsening of the main illness. 相似文献
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Camiña-Tato M Morcillo-Suárez C Bustamante MF Ortega I Navarro A Muntasell A López-Botet M Sánchez A Carmona P Julià E Tortola MT Audí L Oksenberg JR Martin R Montalban X Comabella M 《Journal of immunology (Baltimore, Md. : 1950)》2010,185(9):5392-5404
The granule-dependent exocytosis pathway is an important mechanism to induce apoptosis by CD8(+) T cells and NK cells and involves lytic molecules such as perforin. In the current study, we investigated the perforin 1 gene (PRF1) as a candidate for multiple sclerosis (MS) susceptibility in the Spanish population. We genotyped three PRF1 single nucleotide polymorphisms (rs885822, rs10999426, and rs3758562) in 420 patients with MS and 512 controls. Associations of PRF1 polymorphisms with the disease were restricted to male patients with MS, and the finding was consistently observed at the allele, genotype, and haplotype levels. Gender-associated differences were validated in an additional replication cohort comprised of 292 MS cases and 300 controls. In addition, we identified minor risk haplotypes strongly associated with male patients having primary progressive MS (PPMS). Further characterization of male patients with PPMS carrying the risk haplotypes by means of gene expression microarrays revealed overrepresentation of the cell killing gene ontology category among downregulated genes in these patients compared with male patients with PPMS carrying protective haplotypes. Moreover, PRF1 mRNA expression levels were significantly lower in patients with risk haplotypes, and changes in perforin protein expression by CD8(+) T cells mirrored those observed in gene expression. These findings suggest a gender dimorphism in the PRF1 association with MS and point to the presence of a generalized defect in the expression of genes that code for proteins involved in cell killing in a subgroup of male patients with PPMS. 相似文献
108.
Jorge Martínez Pablo Vargas Modesto Luceño Ángeles Cuadrado 《Plant Systematics and Evolution》2010,289(3-4):223-235
The subgenus Xiphium is one of the six infrageneric divisions of the genus Iris. Chromosome numbers of six of the seven Xiphium species are known. Here the aim was to infer genetic and phylogenetic relationships based on chromosome numbers, chromosome markers and plastid sequences. Chromosomal locations of 5S and 45S rDNA loci were determined in 19 populations of the 7 species by fluorescence in situ hybridization (FISH). Additionally, the trnL–trnF plastid spacer was sequenced and a phylogenetic analysis performed. Based on chromosome markers, subgenus Xiphium species were classified into four groups that differed in the number and locations of both types of nrDNA: (1) I. tingitana (2n = 28), I. filifolia (2n = 30, 34) and I. xiphium (2n = 34), (2) I. juncea (2n = 32) and I. boissieri (2n = 36), (3) I. serotina (2n = 34) and (4) I. latifolia (2n = 42). Although the trnL–trnF phylogeny was not fully resolved, the sequence analysis showed a well-supported subgroup of I. filifolia, I. tingitana and I. xiphium, as well as I. juncea. FISH physical maps of the Iris subgenus Xiphium taxa are species dependent. I. filifolia, I. tingitana and I. xiphium are very closely related species and share cytogenetic characteristics. Disploidy appears to have been central in the evolution of this subgenus, given a series of chromosome numbers (2n = 28, 30, 32, 34, 36, 42) and our phylogenetic results. Clear differences were found among European and African populations of I. filifolia. A different taxonomic treatment of I. filifolia is supported for populations on both sides of the Strait of Gibraltar. 相似文献
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110.
Application of multivariate resolution methods to the study of biochemical and biophysical processes
Multivariate resolution methods make up a set of mathematical tools that may be applied to the analysis and interpretation of spectroscopic data recorded when monitoring a physical or chemical process with multichannel detectors. The goal of resolution methods is the recovery of chemical and/or physical information from the experimental data. Such data include, for example, the number of intermediates present in a reaction, the rate or equilibrium constants, and the spectra for each one of those intermediates. Multivariate resolution methods have been shown to be useful for the study of biophysical and biochemical processes such as folding/unfolding of proteins or nucleic acids. The present article reviews the most frequently used resolution methods, the limitations on their use, and their latest applications in protein and nucleic acid research. 相似文献