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991.
992.
Carlos Lorenzo Manuel Serrano‐Ríos María T. Martínez‐Larrad Rafael Gabriel Ken Williams Juan A. Gmez‐Gerique Michael P. Stern Steven M. Haffner 《Obesity (Silver Spring, Md.)》2003,11(12):1480-1487
Objective: To compare the expression of the metabolic syndrome in Spain and San Antonio, TX, two populations with major differences regarding their cardiovascular risk profile. Research Methods and Procedures: Cross‐sectional analysis of population‐based, epidemiological surveys using the metabolic syndrome definition of the National Cholesterol Education Program. In San Antonio, we limited our analysis to non‐Hispanic whites because non‐Hispanic whites are largely of European ancestry (n = 1339 in San Antonio and 2947 in Spain) Results: In men, increased central adiposity was more prevalent in San Antonio than in Spain (29.7 vs. 23.0%, p < 0.0001); in women, it was less prevalent in San Antonio than in Spain (40.2 vs. 66.4%, p < 0.0001). The metabolic syndrome followed that same pattern: more prevalent in men (28.9 vs. 20.8%, p = 0.019) and less in women from San Antonio (27.1 vs. 30.9%, p < 0.0001). In subjects with the metabolic syndrome, most women had increased central adiposity (92.6% in San Antonio and 97.5% in Spain), and most men had either increased central adiposity or blood pressure (99.2% in San Antonio and 95.0% in Spain). Discussion: Contrary to men, the metabolic syndrome is more prevalent in Spanish women than in women from San Antonio with differences that mirror differences in central adiposity. Central adiposity and blood pressure may be used to exclude the metabolic syndrome. Considering recent secular trends in obesity, we predict there will be an increase in the prevalence of the metabolic syndrome in both populations in the coming years. 相似文献
993.
Julian Santiago-Moreno Rafael J. Astorga Inmaculada Luque Miguel A. Coloma Adolfo Toledano-Díaz Antonio Pulido-Pastor Felix Gómez-Guillamon Ricardo Salas-Vega Antonio López-Sebastián 《Cryobiology》2009,59(3):357-362
The method of sperm recovery may influence the initial quality of sperm samples and their response to freezing–thawing. The aim of the present work was to compare two methods for collecting epididymal spermatozoa in order to improve the quality of recovered sperm and reduce possible contamination. Testes were obtained from 23 legally hunted, adult ibex males. The sperm mass of the right epididymis was collected by small longitudinal and transverse cuts made in the cauda epididymidis. The sperm mass of the left epididymis was collected by retrograde flushing from the vas deferens to the cauda epididymidis (using a cannula), employing a Tris, citric acid, glucose, egg yolk-based medium. The flushing method recovered more spermatozoa (P < 0.001) than the cutting method. After freezing–thawing, greater acrosomes damage (P < 0.001) and more morphological abnormalities (P < 0.05) were seen among the sperm cells recovered by the cutting method than among those obtained by retrograde flushing. The method of sperm recovery did not, however, influence the microbial contamination rate. In frozen–thawed samples that were microbially contaminated, motility was significantly reduced (P < 0.05) and membrane integrity tended to be poorer (P = 0.06). In conclusion, retrograde flushing is recommended for ibex sperm collection since it would appear that microbial contamination is no more of a problem than that encountered with the cutting method, while a larger number of sperm cells more resistant to freezing–thawing can be obtained. 相似文献
994.
Rafael Lira Alejandro Casas Rocío Rosas-López Martín Paredes-Flores Edgar Pérez-Negrón Selene Rangel-Landa Leonor Solís Ignacio Torres Patricia Dávila 《Economic botany》2009,63(3):271-287
Traditional Knowledge and Useful Plant Richness in the Tehuacán–Cuicatlán Valley, Mexico. This study systematizes ethnobotanical information about the interactions between people and plants, ethnofloristic richness,
the relative importance of useful species richness in relation to general species richness, and plant management in the Tehuacán–Cuicatlán
Valley of central Mexico. The study recorded a total of 1,605 useful vascular plant species (61.2% of the total species richness
of the regional vascular flora), this being the region with the highest absolute richness of useful plant species in Mexico.
The null hypothesis that plant families with a higher number of useful species would be those having a higher general species
richness was analyzed through residuals method. The plant families richest in useful species were Poaceae, Asteraceae, Cactaceae,
Cyperaceae, Mimosaceae, and Solanaceae, most of which also have the highest general floristic richness. However, analyses
of use categories did not generally corroborate our hypothesis. About 1,335 of the useful species are wild, more than 500
species are submitted to some type of management (62 species are tolerated, 34 protected, 50 enhanced, and 358 cultivated),
but only a few have been studied to document their process of domestication. This information can be useful for developing
regional strategies of sustainable management of plant resources. 相似文献
995.
996.
This study examined p27 expression in a cohort of salivary malignancies (n = 74) for a prolonged period (20 years). Reduction of p27 expression was found to be a most powerful predictor for poor survival
and more so when the tumor concurrently expressed high levels of p53, TUNEL and heparanase markers, dramatically dropping
the patient survival probability to 0! While no patient whose tumor-staining profile included: p27 > 50%, p53 = 0, TUNEL = 0
and heparanase = 0, died of the disease during the 20-year follow up, the median of survival of the group with p27 ≤ 50%,
p53 > 0, TUNEL > 0 and heparanase > 0 was only 39 months. The survival probabilities of these two groups at 5 years were 100
and 50%, respectively, and at 20 years they were 100 and 0%, respectively (P = 0.05). Significant p27 reduction also resulted in significantly larger tumor size (T value), higher spread of neck metastasis and extra capsular spread and in more advanced disease (higher stage). Significant
correlation rates were found between age and poor survival, age and reduced p27 expression, and reduced p27 expression and
other general co-existing malignancies, indicating p27 reduction as part of a general phenomenon—age related mutagenesis.
Significantly more extensive therapy applied to patients with salivary reduced-p27 tumors could not prevent the rise in mortality
rate, questioning the justification for extensive therapy which is naturally accompanied by higher morbidity. Additional therapeutic
tools for fighting salivary cancer, possibly based on the new understanding of the p27, p53, TUNEL and heparanase carcinogenic
network, are necessary. 相似文献
997.
Yamashita T Deguchi K Sehara Y Lukic-Panin V Zhang H Kamiya T Abe K 《Neurochemical research》2009,34(4):707-710
Possible strategies for treating ischemic stroke include: (1) Neuroprotection: preventing damaged neurons from undergoing
apoptosis in the acute phase of cerebral ischemia; (2) Stem cell therapy: the repair of broken neuronal networks with newly
born neurons in the chronic phase of cerebral ischemia. Firstly, we studied the neuroprotective effect of a calcium channel
blocker, azelnidipine, or a by-product of heme degradation, biliverdin, in the ischemic brain. These results revealed both
azelnidipine and biliverdin had a neuroprotective effect in the ischemic brain through their anti-oxidative property. Secondly,
we investigated the role of granulocyte colony-stimulating factor (G-CSF) by administering G-CSF to rats after cerebral ischemia
and found G-CSF plays a critical role in neuroprotection. Lastly, we developed a restorative stroke therapy with a bio-affinitive
scaffold, which is able to provide an appropriate environment for newly born neurons. In the future, we will combine these
strategies to develop more effective therapies for treatment of strokes.
Special issue article in honor of Dr. Akitane Mori. 相似文献
998.
999.
María Prez-Caro Csar Cobaleda Ins Gonzlez-Herrero Carolina Vicente-Dueas Camino Bermejo-Rodríguez Margarita Snchez-Beato Alberto Orfao Beln Pintado Teresa Flores Manuel Snchez-Martín Rafael Jimnez Miguel A Piris Isidro Snchez-García 《The EMBO journal》2009,28(1):8-20
In human cancers, all cancerous cells carry the oncogenic genetic lesions. However, to elucidate whether cancer is a stem cell-driven tissue, we have developed a strategy to limit oncogene expression to the stem cell compartment in a transgenic mouse setting. Here, we focus on the effects of the BCR-ABLp210 oncogene, associated with chronic myeloid leukaemia (CML) in humans. We show that CML phenotype and biology can be established in mice by restricting BCR-ABLp210 expression to stem cell antigen 1 (Sca1)+ cells. The course of the disease in Sca1-BCR-ABLp210 mice was not modified on STI571 treatment. However, BCR-ABLp210-induced CML is reversible through the unique elimination of the cancer stem cells (CSCs). Overall, our data show that oncogene expression in Sca1+ cells is all that is required to fully reprogramme it, giving rise to a full-blown, oncogene-specified tumour with all its mature cellular diversity, and that elimination of the CSCs is enough to eradicate the whole tumour. 相似文献
1000.
Veerle Vanderheyden Takuya Wakai Geert Bultynck Humbert De Smedt Jan B. Parys Rafael A. Fissore 《Cell calcium》2009,46(1):56-64
Egg activation and further embryo development require a sperm-induced intracellular Ca2+ signal at the time of fertilization. Prior to fertilization, the egg's Ca2+ machinery is therefore optimized. To this end, during oocyte maturation, the sensitivity, i.e. the Ca2+ releasing ability, of the inositol 1,4,5-trisphosphate receptor type 1 (IP3R1), which is responsible for most of this Ca2+ release, markedly increases. In this study, the recently discovered specific Polo-like kinase (Plk) inhibitor BI2536 was used to investigate the role of Plk1 in this process. BI2536 inactivates Plk1 in oocytes at the early stages of maturation and significantly decreases IP3R1 phosphorylation at an MPM-2 epitope at this stage. Moreover, this decrease in Plk1-dependent MPM-2 phosphorylation significantly lowers IP3R1 sensitivity. Finally, using in vitro phosphorylation techniques we identified T2656 as a major Plk1 site on IP3R1. We therefore propose that the initial increase in IP3R1 sensitivity during oocyte maturation is underpinned by IP3R1 phosphorylation at an MPM-2 epitope(s). 相似文献