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641.
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Vanags T Budimlic M Herbert E Montgomery MM Vickers T 《Advances in physiology education》2012,36(2):125-130
Students struggle with the volume and complexity of physiology terminology. We compared first-year undergraduate psychology students' learning of physiological terms using two teaching methods: one verbal (control group; n = 16) and one spatial and multisensory (experimental group; n = 19). The experimental group used clear plastic shower caps to mark brain regions and affix labels to another participant's head. The control group learned the material verbally through a game. When tested verbally, both the control and experimental groups recalled more of the 10 terms immediately after the activity (+106% and +83%, respectively) and 2 wk later (+53% and +31%, respectively) than at the pretest (P < 0.0005). When participants' knowledge was tested spatially (labeling a brain diagram), the experimental group recalled more terms at the posttest (+76%) and followup (+73%) than at the pretest (P < 0.0005), but the control group who showed no improvement at either time point (+12% and +14%, respectively). These findings support the notion that spatial and multisensory learning produces improved spatial recall over time while also supporting the notion of transfer-appropriate processing. 相似文献
643.
Ceballos I Mosquera S Angulo M Mira JJ Argel LE Uribe-Velez D Romero-Tabarez M Orduz-Peralta S Villegas V 《Microbial ecology》2012,64(3):641-653
Mycosphaerella fijiensis is the etiological agent of Black Sigatoka, a fungal disease that affects production of banana and plantain crops in tropical regions. The sizes of cultivable epiphytic and endophytic bacterial populations, aerobic endospore forming bacteria (AEFB), and antagonist bacteria against M. fijiensis isolated from three Musa spp. cultivars from Urabá (Colombia) were studied, in order to find a suitable screening strategy to isolate antagonistic bacteria. Most of the variability found in the epiphytic and endophytic bacterial community sizes among fruit trees was explained by the cultivar differences. We found population sizes ranging from 1.25?×?10(3) to 9.64?×?10(5)?CFU/g of fresh leaf and found that 44?% of total cultivable bacteria belong to the AEFB group. We isolated 648 AEFB from three different cultivars and assessed their antagonistic activity against M. fijiensis using the cell-free supernatant obtained from bacterial liquid cultures in three different in vitro assays. Five percent of those bacteria showed higher percent inhibition than the positive control Bacillus subtilis UA321 has (percent inhibition?=?84?±?5) in the screening phase. Therefore, they were selected as antagonistic bacteria against the pathogen. The strains with the highest percentage of antagonism were found in older leaves for the three cultivars, given support to recommend this group of leaves for future samplings. Some of these isolated bacteria affected the mycelium and ascospores morphology of the fungus. They also presented in vitro characteristics related to a successful colonization of the phylloplane such as indolic compounds, surfactant production, and biofilm formation, which makes them possible, potential candidates as biological control agents. 相似文献
644.
Zygosaccharomyces bailii is the most tolerant yeast species to acetic acid-induced toxicity, being able to grow in the presence of concentrations of this food preservative close to the legal limits. For this reason, Z. bailii is the most important microbial contaminant of acidic food products but the mechanisms behind this intrinsic resistance to acetic acid are very poorly characterized. To gain insights into the adaptive response and tolerance to acetic acid in Z. bailii, we explored an expression proteomics approach, based on quantitative 2DE, to identify alterations occurring in the protein content in response to sudden exposure or balanced growth in the presence of an inhibitory but nonlethal concentration of this weak acid. A coordinate increase in the content of proteins involved in cellular metabolism, in particular, in carbohydrate metabolism (Mdh1p, Aco1p, Cit1p, Idh2p, and Lpd1p) and energy generation (Atp1p and Atp2p), as well as in general and oxidative stress response (Sod2p, Dak2p, Omp2p) was registered. Results reinforce the concept that glucose and acetic acid are coconsumed in Z. bailii, with acetate being channeled into the tricarboxylic acid cycle. When acetic acid is the sole carbon source, results suggest the activation of gluconeogenic and pentose phosphate pathways, based on the increased content of several proteins of these pathways after glucose exhaustion. 相似文献
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Karin Neukam José A. Mira Antonio Collado Antonio Rivero-Juárez Patricia Monje-Agudo Josefa Ruiz-Morales María José Ríos Dolores Merino Francisco Téllez Inés Pérez-Camacho María Carmen Gálvez-Contreras Antonio Rivero Juan A. Pineda HEPAVIR SEG-HEP- Study Group of the Sociedad Andaluza de Enfermedades Infecciosas 《PloS one》2016,11(2)
Objective
To assess the current frequency of ART-associated grade 3–4 transaminase elevations (TE) and grade 4 total bilirubin elevations (TBE) in HIV-infected patients with chronic hepatitis B and/or C, who start a new regimen of ART.Patients and Methods
A total of 192 pre-treated or treatment-naive HIV infected patients with HBV and/or HCV-coinfection who started ART in eight Southern Spanish centers from July/2011-December/2013, were followed for 12 months in this prospective study.Results
Forty-one (21.4%) subjects had been naïve to ART, median (IQR) follow-up was 11.6 (5.6–12.9) months. The most frequently initiated NRTI were tenofovir/emtricitabine [49 patients (25.5%)]. Eighty-nine (46.4%) patients started a ritonavir-boosted protease inhibitor and 77 (40.1%) individuals a NNRTI. Raltegravir and maraviroc were initiated in 24 (12.5%) and 9 (4.7%) individuals. Ten [5.21%; 95% confidence interval (CI): 2.53%-9.37%] patients presented grade 3 TE, while 8 (4.17%; 95%CI: 1.82%-8.04%) subjects showed grade 4 TBE. No episodes of grade 4 TE or ART discontinuation due to hepatotoxic events were observed. The use of ritonavir-boosted atazanavir was the only independent predictor for grade 4 TBE [adjusted odds ratio: 7.327 (95%CI: 1.417–37.89); p = 0.018] in an analysis adjusted for age, sex and baseline HIV-RNA levels, while no factor could be independently associated with grade 3–4 TE.Conclusions
Currently, the frequency of severe ART-associated TE and TBE under real-life conditions in patients with chronic viral hepatitis is similar to what has been reported previously. However, episodes of grade 4 TE are less frequent and severe TE appears to be of lesser concern. 相似文献647.
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Amira Mira Wael Alkhiary Qinchang Zhu Toshinori Nakagawa Hai‐Bang Tran Yhiya M. Amen Kuniyoshi Shimizu 《化学与生物多样性》2016,13(10):1307-1315
Isoepoxypteryxin is the major coumarin of a Japanese medicinal plant Angelica shikokiana. This research was designed to study the effect of structural changes through fungal biotransformation on the reported biological activities of isoepoxypteryxin. Among the tested microorganisms, only Cordyceps sinensis had enzymes that could catalyze the ester hydrolysis and the reductive cleavage of the epoxide ring of isoepoxypteryxin, separately, to give two more polar metabolites (+)‐cis‐khellactone ( P1 ) and a new coumarin derivative (+)‐cis‐3′‐[(2‐methyl‐3‐hydroxybutanoyl)oxy]‐4′‐acetoxy‐3′,4′‐dihydroseselin ( P2 ), respectively. The polar metabolite P2 showed stronger cytotoxicity and higher selectivity than isoepoxypteryxin. On the molecular level, P2 showed more in vitro inhibition of both tubulin polymerization and histone deacetylase 8 (HDAC8). Similarly, P2 showed more neuroprotection against amyloid beta fragment 1 – 42 (Aβ1 – 42)‐induced neurotoxicity in human neuroblastoma cells (SH‐SY5Y) and exhibited more inhibition of the in vitro aggregation of Aβ1 – 42. Both metabolites showed stronger antiplatelet aggregation by increased inhibition of thromboxane‐A2 synthase (TXS) activity and thromboxane‐A2 (TXA2) production. This study is the first to describe the improved cytotoxic, neuroprotective, and antiplatelet aggregation activities of isoepoxypteryxin through its biotransformation by C. sinensis. 相似文献
650.