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61.
62.
Drink composition, voluntary drinking, and fluid balance in exercising, trained, heat-acclimatized boys 总被引:2,自引:0,他引:2
Rivera-Brown Anita M.; Gutierrez Randall; Gutierrez Juan Carlos; Frontera Walter R.; Bar-Or Oded 《Journal of applied physiology》1999,86(1):78-84
This study examinedthe effects of beverage composition on the voluntary drinking pattern,body fluid balance, and thermoregulation of heat-acclimatized trainedboys exercising intermittently in outdoor conditions (wet bulb globetemperature 30.4 ± 1.0°C). Twelve boys (age 13.4 ± 0.4 yr) performed two 3-h sessions, each consisting of four20-min cycling bouts at 60% maximal aerobic power alternating with25-min rest. One of two beverages was assigned: unflavored water (W) orflavored water plus 6% carbohydrate and 18 mmol/l Na (CNa). Drinkingwas ad libitum. Total intake was higher(P < 0.05) during CNa (1,943 ± 190 g) compared with W (1,470 ± 143 g). Euhydration wasmaintained with CNa (+0.18% body wt), but a mild dehydration resultedwith W (0.94% body wt; P < 0.05). Sweat loss, much higher than previously published for children of similar age, was similar between conditions (CNa = 1,644.7 ± 117.5; W = 1,750.2 ± 152.7 g). The increase in rectaltemperature (CNa = 0.86 ± 0.3; W = 0.76 ± 0.1°C), heartrate, and all perceptual variables did not differ between conditions.In conclusion, a flavored carbohydrate-electrolyte drink preventsvoluntary dehydration in trained heat-acclimatized boys exercising in atropical climate despite their large sweat losses. Because hydrationchanges were minor, the thermoregulatory strain observed was similarbetween conditions. 相似文献
63.
Pérez-Simón JA Valverde B Martínez A Tabernero D Almeida J Gutierrez N San Miguel JF Orfao A 《Cytometry》1999,38(1):24-29
Although a variable proportion of multiple myeloma patients can achieve response with conventional chemotherapy, residual tumor cells, which are refractory, finally reemerge leading to disease progression. The expression of the multidrug resistance protein (MDR1) has been one of the most extensively explored mechanisms of drug resistance and has been related to a poor response to chemotherapy in several human tumors. Nevertheless, a careful analysis of the literature on MDR1 expression in multiple myeloma (MM) shows the existence of disturbing discrepancies as regards both the incidence of MDR1 over-expression and its clinical value. A prerequisite for the assessment of MDR1 in tumor cells should be the identification of the neoplastic cells present in the sample. This is particularly important in MM, where the percentage of tumor cells in bone marrow (BM) is relatively low. In the present study we have analyzed the functional expression of MDR1 in BM plasma cells (PC), from a group of 40 untreated MM patients. For that purpose, the rhodamine 123 efflux assay was used in combination with specific staining for plasma cells (CD38 strong+). The mean fluorescence channel (MFC) of rhodamine 123 in myelomatous PC from MM patients was 311 and 110 after incubating cells with this fluorochrome for 15 and 60 min, respectively. The median percentage of rhodamine 123 elimination by BM PC was of 61% (range: 0.29 to 88%). Upon analyzing the relationship between the ability of myelomatous PC to eliminate rhodamine 123 and other clinical and biological disease characteristics we found that, within the group of patients displaying high MDR1 expression (>61% rhodamine efflux), there was a higher incidence of cases with bone disease (P = 0.014) and advanced clinical stages (P = 0.031), greater calcium (P = 0.007) and creatinine serum levels (P = 0.061), and lower levels of albumin in serum (P = 0.015). All these parameters are usually associated with a poor prognosis. When we analyzed the possible relationship between the ability of BM PC to eliminate rhodamine 123 and the presence of numerical chromosome abnormalities we observed that a low MDR1 expression was related to a higher incidence of trisomies of chromosomes 6 and 17, although these differences did not reach statistical significance (P = 0.06). In spite of these associations, from the prognostic point of view, MDR1 expression did not correlate with other relevant prognostic factors, response to treatment (P = 0.38) or overall survival (P = 0.12). 相似文献
64.
Over the last decade isothermal titration calorimetry (ITC) has developed from a specialist method which was largely restricted in its use to dedicated experts, to a major, commercially available tool in the arsenal directed at understanding molecular interactions. The number of those proficient in this field has multiplied dramatically, as has the range of experiments to which this method has been applied. This has led to an overwhelming amount of new data and novel applications to be assessed. With the increasing number of publications in this field comes a need to highlight works of interest and impact. In this overview of the literature we have attempted to draw attention to papers and issues for which both the experienced calorimetrist and the interested dilettante hopefully will share our enthusiasm. 相似文献
65.
66.
Carlos A Aguilar-Salinas Andréia Assis-Luores-Vale Benjamín Stockins Hector Mario Rengifo Dondici José Filho Abrahão Afiune Neto Marcílio Lísia Rabelo Kerginaldo Paulo Torres Egídio Paulo de José Oliveira Carlos Alberto Machado Eliana Reyes Victor Saavedra Fernando Florenzano Ma Victoria Hernández Hernandez Sergio Jiménez Erika Ramírez Cuauhtémoc Vazquez Saul Salinas Ismael Hernández Octavio Medel Ricardo Moreno Paula Lugo Ricardo Alvarado Roopa Mehta Victor Gutierrez Francisco J Gómez Pérez 《Cardiovascular diabetology》2004,3(1):1-6
Background
Microalbuminuria and subsequent progression to proteinuria and nephropathy is associated with increased oxidative stress, increased inflammatory cytokines and increased cardiovascular (CVD) risk. The common functional IL-6 -174G>C gene variant is also associated with elevated levels of inflammatory cytokines and CVD risk.Methods
The aim of this study was to examine the association between the IL-6 -174G>C gene variant with plasma total antioxidant status (TAOS) in 552 subjects with type 2 diabetes in relation to urinary protein excretion.Results
In subjects free from CVD, there was a significant interaction between urinary protein excretion (normoalbuminuria/ microalbuminuria/proteinuria) and the -174C allele (compared to -174GG) in determining plasma TAOS (p value for interaction = 0.03). In the -174C allele carriers there was a significant association between plasma TAOS and urinary protein excretion: normalbuminuria v microalbuminuria v proteinuria: 44.30% ± 11.32 vs. 39.74% ± 14.83 vs. 37.93% ± 16.42, ANOVA p = 0.025. In those with CVD, no interaction or association was observed with the -174C allele (p = 0.246).Conclusion
The IL-6 -174G>C gene variant is associated with differences in plasma oxidative stress in response to altered protein excretion in subjects with type 2 diabetes. 相似文献67.
Probanza A Mateos JL Lucas García JA Ramos B De Felipe MR Gutierrez Mañero FJ 《Microbial ecology》2001,41(2):140-148
The effect of co-inoculation with Pisolithus tinctorius and a PGPR belonging to the genus Bacillus (Bacillus licheniformis CECT 5106 and Bacillus pumilus CECT 5105) in enhancing growth of Pinus pinea plants and the changes that occurred in rhizosphere microbial communities and the degree of mycorrhization were evaluated.
Both bacterial strains of Bacillus promote the growth of Pinus pinea seedlings, but this biological effect does not imply a synergic effect with mycorrhizal infection. However, the positive
response to mycorrhiza in a longer-term experiment it could be expected. The introduction of both inocula causes an lateration
in the microbial rhizosphere composition, despite the low levels of inocula that were found at the end of the assay. 相似文献
68.
Srinivasan J Pires-daSilva A Gutierrez A Zheng M Jungblut B Witte H Schlak I Sommer RJ 《Evolution & development》2001,3(4):229-240
SUMMARY To identify the mechanisms by which molecular variation is introduced into developmental systems, microevolutionary approaches to evolutionary developmental biology have to be taken. Here, we describe the molecular and developmental characterization of laboratory strains of the nematode genus Pristionchus , which lays a foundation for a microevolutionary analysis of vulva development. We describe 13 laboratory strains of the Pristionchus genus that are derived from natural isolates from around the world. Mating experiments and ITS sequence analysis indicated that these 13 strains represent four different species: the gonochoristic species P. lheritieri and three hermaphroditic species, P. pacificus , P. maupasi , and an as yet undescribed species Pristionchus sp., respectively. P. pacificus is represented by five different strains isolated from California, Washington, Hawaii, Ontario, and Poland. Developmental differences during vulva formation are observed between strains from different species but also between strains of P. pacificus , like the strains from California and Poland. In particular, redundant developmental mechanisms present during vulva formation in P. pacificus var. California are absent in other strains. Amplified restriction fragment length polymorphism (AFLP) analyses of the P. pacificus strains revealed that the American strains are highly polymorphic. In contrast, the developmentally distinct strain from Poland is identical to the Californian strain, suggesting that the developmental differences rely on a small number of changes in developmental control genes rather than the accumulation of changes at multiple loci. 相似文献
69.
The gypsy moth, Lymantria dispar, produces two structurally and genetically distinct types of spermatozoa. The eupyrene spermatozoa are genetically haploid and structurally typical. The apyrene spermatozoa are anucleate and structurally different from eupyrene spermatozoa. To understand further the events contributing to meiotic chromosome missegregation in apyrene spermatocytes, we examined the progression of meiosis in these cells with respect to their eupyrene counterparts. Chromosomal bouquet formation and fusion of nucleolar organizing regions are disrupted in apyrene nuclei. In addition, the chromatin of apyrene nuclei is prematurely and extremely condensed compared with that of eupyrene nuclei. An antibody to the conserved synaptonemal complex protein 3 (SCP3) labeled eupyrene pachytene chromosomes, but not apyrene pachytene chromosomes. In addition, apyrene meiotic spindles are missing a subset of microtubules, which likely include kinetochore microtubules. Because the condensation behavior of meiotic chromatin in apyrene spermatocytes deviates from that of eupyrene spermatocytes, we examined the appearance and distribution of the phosphorylated form of histone H3, but no significant differences in histone H3 phosphorylation were found between apyrene and eupyrene spermatocytes. We argue that because a pachytene checkpoint is not initiated in apyrene spermatocytes, this system may provide a way to understand better the underlying biochemical connections between pairing, recombination, synapsis, kinetochore assembly and segregation of chromosomes during meiosis in a higher eukaryote. 相似文献
70.
Heise N Gutierrez AL Mattos KA Jones C Wait R Previato JO Mendonça-Previato L 《Glycobiology》2002,12(7):409-420
Complex glycoinositolphosphoryl ceramides (GIPCs) have been purified from a pathogenic encapsulated wild-type (WT) strain of Cryptococcus neoformans var. neoformans and from an acapsular mutant (Cap67). The structures of the GIPCs were determined by a combination of tandem mass spectrometry, nuclear magnetic resonance spectroscopy, methylation analysis, gas chromatography-mass spectrometry, and chemical degradation. The main GIPC from the WT strain had the structure Manp(alpha1-3)[Xylp(beta1-2)] Manp(alpha1-4)Galp(beta1-6)Manp(alpha1-2)Ins-1-phosphoryl ceramide (GIPC A), whereas the compounds from the acapsular mutant were more heterogeneous in their glycan chains, and variants with Manp(alpha1-6) (GIPC B), Manp(alpha1-6) Manp(alpha1-6) (GIPC C), and Manp(alpha1-2)Manp(alpha1-6)Manp(alpha1-6) (GIPC D) substituents linked to the nonreducing terminal mannose residue found in the WT GIPC A were abundant. The ceramide moieties of C. neoformans GIPCs were composed of a C(18) phytosphingosine long-chain base mainly N-acylated with 2-hydroxy-tetracosanoic acid in the WT GIPC while in the acapsular Cap67 mutant GIPCs, as well as 2-hydroxy-tetracosanoic acid, the unusual 2,3-dihydroxy-tetracosanoic acid was characterized. In addition, structural analysis revealed that the amount of GIPC in the WT cells was fourfold less of that in the acapsular mutant. 相似文献