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101.
Despite numerous endometrial cancer cell lines, little is know about the progression and transition of primary cultured endometrial tumours. Herein, a stage I grade III endometrial adenocarcinoma was maintained in primary culture and the phenotypic and protein expression changes were observed in relation to passage number. At early passage numbers, cultured human endometrial cancer (CHEC) cells displayed classic epithelial cell morphology, growing in groups in a glandular structure and staining positive for cytokeratin. However, with increasing passage number, CHEC cells changed in morphology to display a stromal phenotype which was accompanied by a significant reduction in cytokeratin and increases in alpha-actin and vimentin expression. Simultaneous culture of stromal cells isolated from the original tumour failed to show the same morphological characteristics or protein expression patterns. We further characterised CHEC cells through a screening of cancer related proteins, among others, caveolin-1 and Tissue factor in comparison with established cancer cell lines and corresponding non-cancerous cells. This report demonstrates that endometrial adenocarcinoma cells in culture can undergo phenotypic and protein expression changes reminiscent of epithelial-mesenchymal transition. This work suggests that primary tumours and cell lines displaying stromal morphologies may have undergone epithelial-mesenchymal transition from an adenocarcinoma origin.  相似文献   
102.
103.
We have studied the effects of different concentrations of H(2)O(2) on the proliferation of PC-3 prostate carcinoma cells. Since this cell line lacks functional p53, we sought to characterize whether apoptotic response to the oxidative insult was altered such that, unlike in cells containing functional p53 apoptosis may be reduced and replaced by other mechanisms of cellular arrest and death. We did not observe necrosis in PC-3 cells treated with H(2)O(2) concentrations of up to 500 microM. In the presence of 50 microM H(2)O(2), arrest was observed in the G2-phase of the cell cycle, along with p53-independent apoptosis. In the presence of 500 microM H(2)O(2), addition of l-buthionine sulfoximine increased the percentage of apoptotic cell death. Senescence-associated cell arrest was never observed. Moreover, some of the treated cells seemed to be resistant to oxidative damage. These cells re-entered the cell cycle and proliferated normally. Analysis of the expression of p21(waf1) and of p21 protein levels, as well as the activity of caspase-3 and caspase-8, allowed us to characterize some aspects of the arrest of PC-3 cells in G2 and the apoptotic response to oxidative stress in the absence of functional p53.  相似文献   
104.
Genetic diversity at 13 equine microsatellite loci was compared in five endangered Spanish donkey breeds: Andaluza, Catalana, Mallorquina, Encartaciones and Zamorano-Leonesa. All of the equine microsatellites used in this study were amplified and were polymorphic in the domestic donkey breeds with the exception of HMS1, which was monomorphic, and ASB2, which failed to amplify. Allele number, frequency distributions and mean heterozygosities were very similar among the Spanish donkey breeds. The unbiased expected heterozygosity (HE) over all the populations varied between 0.637 and 0.684 in this study. The low GST value showed that only 3.6% of the diversity was between breeds (P < 0.01). Significant deviations from Hardy-Weinberg equilibrium were shown for a number of locus-population combinations, except HMS5 that showed agreement in all analysed populations. The cumulative exclusion probability (PE) was 0.999 in each breed, suggesting that the loci would be suitable for donkey parentage testing. The constructed dendrogram from the DA distance matrix showed little differentiation between Spanish breeds, but great differentiation between them and the Moroccan ass and also with the horse, used as an outgroup. These results confirm the potential use of equine microsatellite loci as a tool for genetic studies in domestic donkey populations, which could also be useful for conservation plans.  相似文献   
105.
Associations between δ13C values and leaf gas exchanges and tree-ring or needle growth, used in ecophysiological compositions, can be complex depending on the relative timing of CO2 uptake and subsequent redistribution and allocation of carbon to needle and stem components. For palaeoenvironmental and dendroecological studies it is often interpreted in terms of a simple model of δ13C fractionation in C3 plants. However, in spite of potential complicating factors, few studies have actually examined these relationships in mature trees over inter- and intra-annual time-scales. Here, we present results from a 4 years study that investigated the links between variations in leaf gas-exchange properties, growth, and dated δ13C values along the needles and across tree rings of Aleppo pine trees growing in a semi-arid region under natural conditions or with supplemental summer irrigation. Sub-sections of tissue across annual rings and along needles, for which time of formation was resolved from growth rate analyses, showed rapid growth and δ13C responses to changing environmental conditions. Seasonal cycles of growth and δ13C (up to ~4‰) significantly correlated (P<0.01) with photosynthetically active radiation, vapour pressure deficit, air temperature, and soil water content. The irrigation significantly increased leaf net assimilation, stomatal conductance and needle and tree-ring growth rate, and markedly decreased needle and tree-ring δ13C values and its sensitivity to environmental parameters. The δ13C estimates derived from gas-exchange parameters, and weighted by assimilation, compared closely with seasonal and inter-annual δ13C values of needle- and tree-ring tissue. Higher stomatal conductances of the irrigated trees (0.22 vs. 0.08 mol m−2 s−1 on average) corresponded with ~2.0‰ lower average δ13C values, both measured and derived. Derived and measured δ13C values also indicated that needle growth, which occurs throughout the stressful summer was supported by carbon from concurrent, low rate assimilation. For Aleppo pine under semi-arid and irrigated conditions, the δ13C of tree-ring and needle material proved, in general, to be a reasonable indicator of integrated leaf gas-exchange properties.  相似文献   
106.
Predicted increases in atmospheric concentration of carbon dioxide (CO2) coupled with increased temperatures and drought are expected to strongly influence the development of most of the plant species in the world, especially in areas with high risk of desertification like the Mediterranean basin. Helianthemum almeriense is an ecologically important Mediterranean shrub with an added interest because it serves as the host for the Terfezia claveryi mycorrhizal fungus, which is a desert truffle with increasingly commercial interest. Although both plant and fungi are known to be well adapted to dry conditions, it is still uncertain how the increase in atmospheric CO2 will influence them. In this article we have addressed the physiological responses of H. almeriense × T. claveryi mycorrhizal plants to increases in atmospheric CO2 coupled with drought and high vapor pressure deficit. This work reports one of the few estimations of mesophyll conductance in a drought deciduous Mediterranean shrub and evaluates its role in photosynthesis limitation. High atmospheric CO2 concentrations help desert truffle mycorrhizal plants to cope with the adverse effects of progressive drought during Mediterranean springs by improving carbon net assimilation, intrinsic water use efficiency and dispersal of the species through increased flowering events.  相似文献   
107.
Rapid identification of Populus L. species and hybrids can be achieved with relatively little effort through the use of primer extension-based single nucleotide polymorphism (SNP) genotyping assays. We present an optimized set of 36 SNP markers from 28 gene regions that diagnose eight poplar species (Populus angustifolia James, Populus balsamifera L., Populus deltoides Bartram, Populus fremontii Watson, Populus laurifolia Ledeb., Populus maximowiczii Henry, Populus nigra L., and Populus trichocarpa Torr. & Gray). A total of 700 DNA sequences from six Populus species (1–15 individuals per species) were used to construct the array. A set of flanking and probe oligonucleotides was developed and tested. The accuracy of the SNP assay was validated by genotyping 448 putatively “pure” individuals from 14 species of Populus. Overall, the SNP assay had a high success rate (97.6 %) and will prove useful for the identification of all Aigeiros Duby and Tacamahaca Spach. species and their early-generation hybrids within natural populations and breeding programs. Null alleles and intraspecific polymorphisms were detected for a few locus/species combinations in the Aigeiros and Tacamahaca sections. When we attempted to genotype aspens of the section Populus (Populus alba L., Populus grandidentata Michx., Populus tremula L., and Populus tremuloides Michx.), the success rate of the SNP array decreased by 13 %, demonstrating moderate cross-sectional transferability.  相似文献   
108.
The prefrontal (PFC) and orbitofrontal cortex (OFC) appear to be associated with both executive functions and olfaction. However, there is little data relating olfactory processing and executive functions in humans. The present study aimed at exploring the role of olfaction on executive functioning, making a distinction between primary and more cognitive aspects of olfaction. Three executive tasks of similar difficulty were used. One was used to assess hot executive functions (Iowa Gambling Task-IGT), and two as a measure of cold executive functioning (Stroop Colour and Word Test-SCWT and Wisconsin Card Sorting Test-WCST). Sixty two healthy participants were included: 31 with normosmia and 31 with hyposmia. Olfactory abilities were assessed using the ‘‘Sniffin’ Sticks’’ test and the olfactory threshold, odour discrimination and odour identification measures were obtained. All participants were female, aged between 18 and 60. Results showed that participants with hyposmia displayed worse performance in decision making (IGT; Cohen’s-d = 0.91) and cognitive flexibility (WCST; Cohen’s-d between 0.54 and 0.68) compared to those with normosmia. Multiple regression adjusted by the covariates participants’ age and education level showed a positive association between odour identification and the cognitive inhibition response (SCWT-interference; Beta = 0.29; p = .034). The odour discrimination capacity was not a predictor of the cognitive executive performance. Our results suggest that both hot and cold executive functions seem to be associated with higher-order olfactory functioning in humans. These results robustly support the hypothesis that olfaction and executive measures have a common neural substrate in PFC and OFC, and suggest that olfaction might be a reliable cognitive marker in psychiatric and neurologic disorders.  相似文献   
109.
Hematologic, protein electrophoresis, serum biochemistry, and cholinesterase values were determined in 36 free-living black stork nestlings (Ciconia nigra) between 25 and 53 days of age in order to establish normal reference values for this population. The following values were evaluated: white blood cell counts, red blood cell counts, packed cell volume, hemoglobin, heterophils, lymphocytes, monocytes, eosinophils, prealbumin, albumin, alpha-globulin, beta-globulin, gamma-globulin, total protein, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, creatine kinase, calcium, phosphorus, iron, cholesterol, glucose, triglycerides, uric acid, urea, creatinine, total solids, bile acids, and butyrylcholinesterase. Sex-dependent differences were observed in hemoglobin, prealbumin, albumin, gamma-globulin, total protein, alkaline phosphatase, and triglycerides. Packed cell volume, butyrylcholinesterase, aspartate aminotransferase, creatine kinase, and creatinine increased with age, whereas albumin, mean cell volume, calcium, phosphorus, cholesterol, and total solids decreased with age. These hematologic and serum biochemistry values can be used as reference ranges in free-living black stork nestlings.  相似文献   
110.
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