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991.
992.
M González-González L Muñoz-Bellvis C Mackintosh C Fontanillo ML Gutiérrez MM Abad O Bengoechea C Teodosio E Fonseca M Fuentes J De Las Rivas A Orfao J María Sayagués 《PloS one》2012,7(8):e42683
Background
Most sporadic colorectal cancer (sCRC) deaths are caused by metastatic dissemination of the primary tumor. New advances in genetic profiling of sCRC suggest that the primary tumor may contain a cell population with metastatic potential. Here we compare the cytogenetic profile of primary tumors from liver metastatic versus non-metastatic sCRC.Methodology/Principal Findings
We prospectively analyzed the frequency of numerical/structural abnormalities of chromosomes 1, 7, 8, 13, 14, 17, 18, 20, and 22 by iFISH in 58 sCRC patients: thirty-one non-metastatic (54%) vs. 27 metastatic (46%) disease. From a total of 18 probes, significant differences emerged only for the 17p11.2 and 22q11.2 chromosomal regions. Patients with liver metastatic sCRC showed an increased frequency of del(17p11.2) (10% vs. 67%;p<.001) and del(22q11.2) (0% vs. 22%;p = .02) versusnon-metastatic cases. Multivariate analysis of prognostic factors for overall survival (OS) showed that the only clinical and cytogenetic parameters that had an independent adverse impact on patient outcome were the presence of del(17p) with a 17p11.2 breakpoint and del(22q11.2). Based on these two cytogenetic variables, patients were classified into three groups: low- (no adverse features), intermediate- (one adverse feature) and high-risk (two adverse features)- with significantly different OS rates at 5-years (p<.001): 92%, 53% and 0%, respectively.Conclusions/Significance
Our results unravel the potential implication of del(17p11.2) in sCRC patients with liver metastasis as this cytogenetic alteration appears to be intrinsically related to an increased metastatic potential and a poor outcome, providing additional prognostic information to that associated with other cytogenetic alterations such as del(22q11.2). Additional prospective studies in larger series of patients would be required to confirm the clinical utility of the new prognostic markers identified. 相似文献993.
994.
JD Coso C González-Millán JJ Salinero J Abián-Vicén L Soriano S Garde B Pérez-González 《PloS one》2012,7(8):e43280
Background
To investigate the cause/s of muscle fatigue experienced during a half-iron distance triathlon.Methodology/Principal Findings
We recruited 25 trained triathletes (36±7 yr; 75.1±9.8 kg) for the study. Before and just after the race, jump height and leg muscle power output were measured during a countermovement jump on a force platform to determine leg muscle fatigue. Body weight, handgrip maximal force and blood and urine samples were also obtained before and after the race. Blood myoglobin and creatine kinase concentrations were determined as markers of muscle damage.Results
Jump height (from 30.3±5.0 to 23.4±6.4 cm; P<0.05) and leg power output (from 25.6±2.9 to 20.7±4.6 W · kg−1; P<0.05) were significantly reduced after the race. However, handgrip maximal force was unaffected by the race (430±59 to 430±62 N). Mean dehydration after the race was 2.3±1.2% with high inter-individual variability in the responses. Blood myoglobin and creatine kinase concentration increased to 516±248 µg · L−1 and 442±204 U · L−1, respectively (P<0.05) after the race. Pre- to post-race jump change did not correlate with dehydration (r = 0.16; P>0.05) but significantly correlated with myoglobin concentration (r = 0.65; P<0.001) and creatine kinase concentration (r = 0.54; P<0.001).Conclusions/significance
During a half-iron distance triathlon, the capacity of leg muscles to produce force was notably diminished while arm muscle force output remained unaffected. Leg muscle fatigue was correlated with blood markers of muscle damage suggesting that muscle breakdown is one of the most relevant sources of muscle fatigue during a triathlon. 相似文献995.
996.
997.
María Sánchez-Aragó Laura Formentini Javier García-Bermúdez José M. Cuezva 《Cell cycle (Georgetown, Tex.)》2012,11(16):2963-2964
Comment on: Formentini L, et al. Mol Cell 2012; 45:731-42. 相似文献
998.
Elda?I?Espa?a-Gamboa Javier?O?Mijangos-Cortés Galdy?Hernández-Zárate Jorge?A?Domínguez?Maldonado Liliana?M?Alzate-GaviriaEmail author 《Biotechnology for biofuels》2012,5(1):82
Background
A modified laboratory-scale upflow anaerobic sludge blanket (UASB) reactor was used to obtain methane by treating hydrous ethanol vinasse. Vinasses or stillage are waste materials with high organic loads, and a complex composition resulting from the process of alcohol distillation. They must initially be treated with anaerobic processes due to their high organic loads. Vinasses can be considered multipurpose waste for energy recovery and once treated they can be used in agriculture without the risk of polluting soil, underground water or crops. In this sense, treatment of vinasse combines the elimination of organic waste with the formation of methane. Biogas is considered as a promising renewable energy source. The aim of this study was to determine the optimum organic loading rate for operating a modified UASB reactor to treat vinasse generated in the production of hydrous ethanol from sugar cane molasses.Results
The study showed that chemical oxygen demand (COD) removal efficiency was 69% at an optimum organic loading rate (OLR) of 17.05 kg COD/m3-day, achieving a methane yield of 0.263 m3/kg CODadded and a biogas methane content of 84%. During this stage, effluent characterization presented lower values than the vinasse, except for potassium, sulfide and ammonia nitrogen. On the other hand, primers used to amplify the 16S-rDNA genes for the domains Archaea and Bacteria showed the presence of microorganisms which favor methane production at the optimum organic loading rate.Conclusions
The modified UASB reactor proposed in this study provided a successful treatment of the vinasse obtained from hydrous ethanol production.Methanogen groups (Methanobacteriales and Methanosarcinales) detected by PCR during operational optimum OLR of the modified UASB reactor, favored methane production.999.
Domínguez-Ruiz J Sanchis J Navarro-Llopis V Primo J 《Journal of economic entomology》2008,101(4):1325-1330
New agricultural techniques are attempting to reduce the application of synthesized pesticides and replace them with new environmentally friendly methods such as mass trapping, mating disruption, or chemosterilization techniques. All these methods are based on the release of a lure for insect attraction or confusion. The success of the chosen method depends on the quality of the attractant emission from the dispenser. Currently, used dispensers with a polymeric matrix and new dispensers with mesoporous inorganic materials were evaluated to obtain more efficient emission kinetics. In this study, the selected pest was the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) and the lure used was trimedlure (TML). The dispensers were validated by means of a field study comparing insect catches with attractant release values. As a result, we have demonstrated that mesoporous dispensers have a clearly longer lifetime than the polymeric plug. Furthermore, the attractant release rate is less dependent on temperature in mesoporous than in polymeric dispensers. 相似文献
1000.
Gómez-León J Villamill L Salger SA Sallum RH Remacha-Triviño A Leavitt DF Gómez-Chiarri M 《Diseases of aquatic organisms》2008,79(2):95-105
Shellfish production is often affected by bacterial pathogens that cause high losses in hatcheries and nurseries. We evaluated the relative survival of larvae and juveniles of 3 Crassostrea virginica oyster lines: (1) GHP, a Rhode Island line; (2) NEHY, a line resistant to dermo and multinucleated sphere X diseases; and (3) FLOWERS, a line resistant to Roseovarius oyster disease, experimental challenge with Vibrio spp. isolates RE22 and RE101, causative agents of bacillary necrosis in Pacific oyster larvae, and the type strain of Roseovarius crassostreae, causative agent of Roseovarius oyster disease. All of the isolates were able to induce significant mortalities in oyster larvae and juveniles. Susceptibility to bacterial challenge in larvae was significantly higher at 25 degrees C than at 20 degrees C. Susceptibility decreased with oyster age; mean survival time ranged from 24 h in oyster larvae to more than 6 wk in juveniles. Significant differences in susceptibility to bacterial challenge were observed between oyster lines; NEHY was the most resistant line overall. Extracellular products (ECPs) from Vibrio sp. RE22 and R. crassostreae, as well as viable bacteria, were toxic to hemocytes from the 3 oyster lines, suggesting that ECPs are involved in pathogenesis and that external and mucosal barriers to infection are major contributors to resistance to bacterial challenge. These protocols will be useful in the elucidation of mechanisms of bacterial pathogenesis and resistance to infection in oysters. 相似文献