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91.
The karyotype of one female Brachyteles arachinoides (E. Geoffroy, 1806) was studied. The specimen exhibited 62 chromosomes, which could be arranged in three clearly distinguishable groups: the first one including 5 pairs of subtelocentric chromosomes, the second one including 8 pairs of metacentric and submetacentric chromosomes and the third one including 18 pairs of acrocentric chromosomes. The X chromosome pair could not be identified.This study was supported by grants from CNPq (SIP 04/011), Brazil. 相似文献
92.
We studied the physiological response to glucose limitation in batch and steady-state (chemostat) cultures of Saccharomyces cerevisiae by following global patterns of gene expression. Glucose-limited batch cultures of yeast go through two sequential exponential growth phases, beginning with a largely fermentative phase, followed by an essentially completely aerobic use of residual glucose and evolved ethanol. Judging from the patterns of gene expression, the state of the cells growing at steady state in glucose-limited chemostats corresponds most closely with the state of cells in batch cultures just before they undergo this "diauxic shift." Essentially the same pattern was found between chemostats having a fivefold difference in steady-state growth rate (the lower rate approximating that of the second phase respiratory growth rate in batch cultures). Although in both cases the cells in the chemostat consumed most of the glucose, in neither case did they seem to be metabolizing it primarily through respiration. Although there was some indication of a modest oxidative stress response, the chemostat cultures did not exhibit the massive environmental stress response associated with starvation that also is observed, at least in part, during the diauxic shift in batch cultures. We conclude that despite the theoretical possibility of a switch to fully aerobic metabolism of glucose in the chemostat under conditions of glucose scarcity, homeostatic mechanisms are able to carry out metabolic adjustment as if fermentation of the glucose is the preferred option until the glucose is entirely depleted. These results suggest that some aspect of actual starvation, possibly a component of the stress response, may be required for triggering the metabolic remodeling associated with the diauxic shift. 相似文献
93.
Background
Estimators of free energies are routinely used to judge the quality of protein structural models. As these estimators still present inaccuracies, they are frequently evaluated by discriminating native or native-like conformations from large ensembles of so-called decoy structures. 相似文献94.
95.
Priming Endothelial Cells With a Melanoma‐Derived Extracellular Matrix Triggers the Activation of αvβ3/VEGFR2 Axis
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97.
Bioactive compounds are considered safe and have been shown to alter genetic and epigenetic profiles of tumor cells. However, many of these changes have been reported at molecular concentrations higher than physiologically achievable levels. We investigated the role of the combinatorial effects of epigallocatechin gallate (EGCG), a predominant polyphenol in green tea, and sodium butyrate (NaB), a dietary microbial fermentation product of fiber, in the regulation of survivin, which is an overexpressed anti-apoptotic protein in colon cancer cells. For the first time, our study showed that the combination treatment induced apoptosis and cell cycle arrest in RKO, HCT-116 and HT-29 colorectal cancer cells. This was found to be regulated by the decrease in HDAC1, DNMT1, survivin and HDAC activity in all three cell lines. A G2/M arrest was observed for RKO and HCT-116 cells, and G1 arrest for HT-29 colorectal cancer cells for combinatorial treatment. Further experimentation of the molecular mechanisms in RKO colorectal cancer (CRC) cells revealed a p53-dependent induction of p21 and an increase in nuclear factor kappa B (NF-κB)-p65. An increase in double strand breaks as determined by gamma-H2A histone family member X (γ-H2AX) protein levels and induction of histone H3 hyperacetylation was also observed with the combination treatment. Further, we observed a decrease in global CpG methylation. Taken together, these findings suggest that at low and physiologically achievable concentrations, combinatorial EGCG and NaB are effective in promoting apoptosis, inducing cell cycle arrest and DNA-damage in CRC cells. 相似文献
98.
Cleber Witt Saldanha Caio Gomide Otoni Diego Ismael Rocha Paulo Cézar Cavatte Kelly da Silva Coutinho Detmann Francisco André Ossamu Tanaka Leonardo Lucas Carnevalli Dias Fábio Murilo DaMatta Wagner Campos Otoni 《Plant Cell, Tissue and Organ Culture》2014,118(1):87-99
This study aimed to evaluate under photoautotrophic conditions the effect of CO2-enriched atmosphere (360 or 1,000 μmol CO2 mol?1 air) combined with two substrate types (agar or Florialite®) in vitro on plants of Pfaffia glomerata, an endangered medicinal species with promising applications in phytotherapy and phytomedicine. The effects of the treatments on the growth, stomatal density, Rubisco activity, carbon isotopic discrimination, metabolite accumulation, photosynthetic pigments and ultrastructural characteristics were investigated. After a 35-day cultivation period, the in vitro-growth of P. glomerata nodal segments under the different treatments resulted in plants with substantial differences in relation to their growth, photosynthetic pigments, stomatal density and leaf ultrastructural characteristics. The enrichment with CO2 coupled with a porous substrate increased the growth of P. glomerata. The stomatal density in the abaxial epidermis more than doubled in response to the high CO2 supply in both supporting types, whereas the Rubisco activity and activation state were both unresponsive to the treatments. Regardless of the CO2 supply, the plants grown in agar displayed higher carbon isotope discrimination than their counterparts grown in Florialite®. We propose that the long-term photosynthetic performance was improved using Florialite® as a growth support in combination with a high CO2 supply. No apparent signs of photosynthetic down-regulation could be found under elevated CO2 conditions. The enrichment of in vitro atmospheres with CO2 coupled with a porous substrate offers new possibilities for improving the growth and production on a commercial scale of high morphological and physiological quality Pfaffia plants. 相似文献
99.
Pedro A. Magalh?es De Saldanha da Gama Hichem Slama Emilie A. Caspar Wim Gevers Axel Cleeremans 《PloS one》2013,8(10)
Here, we ask whether placebo-suggestion (without any form of hypnotic induction) can modulate the resolution of cognitive conflict. Naïve participants performed a Stroop Task while wearing an EEG cap described as a “brain wave” machine. In Experiment 1, participants were made to believe that the EEG cap would either enhance or decrease their color perception and performance on the Stroop task. In Experiment 2, participants were explicitly asked to imagine that their color perception and performance would be enhanced or decreased (non-hypnotic imaginative suggestion). We observed effects of placebo-suggestion on Stroop interference on accuracy: interference was decreased with positive suggestion and increased with negative suggestion compared to baseline. Intra-individual variability was also increased under negative suggestion compared to baseline. Compliance with the instruction to imagine a modulation of performance, on the other hand, did not influence accuracy and only had a negative impact on response latencies and on intra-individual variability, especially in the congruent condition of the Stroop Task. Taken together, these results demonstrate that expectations induced by a placebo-suggestion can modulate our ability to resolve cognitive conflict, either facilitating or impairing response accuracy depending on the suggestion’s contents. Our results also demonstrate a dissociation between placebo-suggestion and non-hypnotic imaginative suggestion. 相似文献
100.
Mark Turlington Aspen Chun Sakshi Tomar Aimee Eggler Valerie Grum-Tokars Jon Jacobs J. Scott Daniels Eric Dawson Adrian Saldanha Peter Chase Yahira M. Baez-Santos Craig W. Lindsley Peter Hodder Andrew D. Mesecar Shaun R. Stauffer 《Bioorganic & medicinal chemistry letters》2013,23(22):6172-6177
Herein we report the discovery and SAR of a novel series of SARS-CoV 3CLpro inhibitors identified through the NIH Molecular Libraries Probe Production Centers Network (MLPCN). In addition to ML188, ML300 represents the second probe declared for 3CLpro from this collaborative effort. The X-ray structure of SARS-CoV 3CLpro bound with a ML300 analog highlights a unique induced-fit reorganization of the S2–S4 binding pockets leading to the first sub-micromolar noncovalent 3CLpro inhibitors retaining a single amide bond. 相似文献