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关键词： Free amino acids   Heat stress   Maguey   Plant growth   Seed provenance   Soluble sugars  

摘要： The assessment of phenotypic variation across populations can help to select genotypes that are potentially resistant to the ongoing and predicted climatic variations. Phenotypic variation is expressed as morphological, physiological, or metabolic changes in response to environmental factors. Agave mapisaga and A. salmiana populations exhibit morphological variation regarding their geographical distribution and due to intense anthropogenic influence. This study aimed to identify metabolic traits in young plants of A. mapisaga and A. salmiana, involved in plant resistance to temperature stress, which can help to understand differences between provenances and between species. Agave plants propagated from four seed origins, collected from three ?pulque? (a fermented beverage) production areas in the state of Hidalgo, Mexico, were assessed. Four-month-old plants of each seed origin (species*provenance) were maintained during one month in growth chambers, at day/night temperature (T) regimes for 12/12 h: (1) 25/25T, (2) 25/15T, and (3) 25/15 plus 45 ?C T for 4 h between 11 am and 3 pm (45T). The plant dry biomass, maximum quantum efficiency of PSII photochemistry (Fv/Fm), total free amino acids (TFAA), total free phenol (TFP), and free soluble sugar concentrations were measured. Minimum values for dry biomass, TFP, glucose, and sucrose concentrations occurred in the 25/25T regime. Plant biomass, and TFAA and glucose concentrations were differently affected by seed provenances;but Fv/Fm rate, or the TFP, fructose, and sucrose concentrations had no relation to seed provenance. Moderate high night temperatures drastically affected the growth and metabolism of A. mapisaga and A. salmiana. In conclusion, the response to different temperature stress treatments depends partly on species, but less on seed provenance.

关键词： Biomarkers   Chronic exposure   Life-history parameters   Non-target organisms   Oral contraceptive   Water contamination  

摘要： The occurrence of pharmaceuticals in aquatic ecosystems and the need to study them have increased over the years since they enter continuously the environment. Besides, these compounds are not intended for applications with environmental purposes, and therefore, little is known about their ecological effects, particularly in non-target organisms, as invertebrate species. Inside these substances, endocrine disrupting compounds (EDCs) have recently come into the limelight, due to environmental concentrations and consequently their detrimental effects on different organisms. 17 alpha-ethinylestradiol (EE2) has been detected in the aquatic environment in various locations around the globe since it is the main synthetic hormone used as a female oral contraceptive and is also applied in veterinary medicine and animal production. The present study was intended to assess the chronic effects of EE2, in the non-target organism as Daphnia magna. Thus, to analyze the individual and subindividual impact, this aquatic organism was chronically exposed (21 days) to 0.00 (control group), 0.10, 1.00, 10.0, and 100 mu g/L of EE2. Results here obtained demonstrated that D. magna exposed to the EE2 concentrations had significant effects in individual (life-history) and sub-individual (biochemical levels) parameters. Alterations as anticipation in the age at first reproduction, a decrease of the growth rate, oxidative stress, and lipid peroxidation were detected, as well as genotoxic damage. Therefore, it was possible to infer that EE2 can disrupt several metabolic pathways and physiological functions of D. magna, since EE2 demonstrated ecotoxicity, at environmentally relevant concentrations. This work reinforces the importance of examining the effects of more relevant exposures (more prolonged and with ecologically pertinent concentrations) of potential endocrine disruptors like EE2, to the freshwater organisms and ecosystem.

关键词： Disposable nappies   Expired food products   Anaerobic co-digestion   Thermal pretreatment   Acid hydrolysis   HRT reduction  

摘要： Used absorbent hygiene products are complex materials (only partially biodegradable) that constitute a significant percentage of municipal solid wastes ending up in landfills. At the same time, food wastes disposed of in landfills have a major contribution to greenhouse gas emissions. In this study, the authors propose the separation of the biodegradable part of used disposable adult nappies and its co-digestion with expired food products, originating from supermarkets. Three different pretreatment schemes were examined, with the meat waste pasteurization treatment scenario leading to the recovery of 427 kJ/ Lfeed, while acid hydrolysis and intense thermal treatment led to a reduction of the recovered energy by 25.5 and 49.4% respectively, even though the hydrogen production, after acid hydrolysis, is almost 2 times higher compared to the other pretreatment schemes. This was caused by impeded methanogenic reactor operation, probably triggered by inhibitory cation concentrations and complex compounds. Finally, the methanogenic reactor during two-stage system operation, with meat pasteurization, was capable of operating with an HRT of 10.6 d, with 67% COD reduction, from an initial feedstock COD of 42 g/L. The reduction of HRT from 20 to 10.6 d exhibited an insignificant effect in specific (per LFeed) methane production. (c) 2020 Elsevier Ltd. All rights reserved.

关键词： Allium fistulosum   Phytotoxicity   Atranorin   Thamnolic acid   Gyrophoric acid  

摘要： Here we report the effects of atranorin (ATR), gyrophoric acid (GPA), and thamnolic acid (TMA) on the physiological, biochemical, and cytological characteristics of Allium fistulosum L. seedlings for the first time. Of the lichen substances investigated, ATR and TAM had the highest phytotoxicity effects. ATR (4000 - 1000 mu M) and TAM (4000 mu M) inhibited the growth processes and increased the intensity of lipid peroxidation in A. fistulosum, and as a result the activities of the protective enzymes peroxidase, catalase, and superoxide dismutase increased, and the contents of photosynthetic pigments in the A. fistulosum seedlings decreased. ATR at concentrations 2000 and 4000 mu M caused decrease of mitotic activity and increase of chromosomal aberrations frequency in root cells. The weakest phytotoxic properties were shown by GPA, which caused no changes in the physiological, cytological, or biochemical parameters of the A. fistulosum seedlings across the entire range of concentrations tested.

关键词： Spatial distribution patterns   Biochemical recurrence   Prostate cancer   Organ-confined   pT2 sub-stages  

摘要： Background: The previous attempts for pT2 substaging of prostate cancer (PCa) were insufficient in providing prognostic subgroups and the search for new prognostic parameters to subcategorize pT2 PCa is, therefore, needed. Therefore, the current study investigated the association between tumor distribution patterns and the biochemical recurrence (BCR)-free survival rate in pT2pN0R0 PCa. Methods: Following radical prostatectomy, the anatomical distribution of PCa in 743 men with pT1-pT3pN0 disease was analyzed to determine 20 types of PCa distribution patterns. Then, 245 men with pT2pN0R0 PCa was considered for prognostic evaluation with a mean follow-up period of 60 months. The spatial distribution patterns of PCa were evaluated using a cMDX-based map model of the prostate. An analysis including 552,049 comparison operations was performed to assist in the evaluation of the similarity levels of the distribution patterns. A k-mean cluster analysis was applied to determine groups with similar distribution patterns. A decision-tree analysis was performed to divide these groups according to frequency of BCR. The BCR-free survival rate was analyzed using Kaplan-Meier curves. Predictors of progression were investigated using a Cox proportional hazards model. Results: BCR occurred in 8.2% of the 245 men with pT2pN0R0 PCa. The median time of recurrence was 60 months (interquartile range [IQR]: 42-77). In univariate and multivariate analyses, the prostate volume and the distribution patterns were independent predictors for BCR, whereas the sub-staging of pT2 tumors, Gleason grading, prostate-specific antigen (PSA) level, and relative tumor volume were not. In the patients with pT2pN0R0 disease, PCa distribution patterns with the apical involvement were significantly associated with the risk of BCR (P = 0.001). Conclusion: The spread tumor patterns with the apical involvement are associated with a high-risk of BCR in the pT2 tumor stage. The vertical tumor spread could be cons

关键词： SH-SY5Y   Dopamine metabolism   Glutathione   Complex I   Glucocerebrosidase  

摘要： Parkinson?s disease is a multifactorial neurodegenerative disease. The cellular pathology includes dopamine depletion, decrease in mitochondrial complex I enzyme activity, lysosomal glucocerebrosidase enzyme activity and glutathione levels. The SH-SY5Y human neuroblastoma cell line is one of the most widely used cell line models for Parkinson?s disease. However, the consensus on its suitability as a model in its proliferative or differentiated state is lacking. In this study, we characterized and compared the biochemical processes most often studied in PD. This in proliferative and differentiated phenotypes of SH-SY5Y cells and several differences were found. Most notably, extracellular dopamine metabolism was significantly higher in differentiated SH-SY5Y. Furthermore, there was a greater variability in glutathione levels in proliferative phenotype (+/- 49%) compared to differentiated (+/- 16%). Finally, enzyme activity assay revealed significant increase in the lysosomal enzyme glucocerebrosidase activity in differentiated phenotype. In contrast, our study has found similarities between the two phenotypes in mitochondrial electron transport chain activity and tyrosine hydroxylase protein expression. The results of this study demonstrate that despite coming from the same cell line, these cells possess some key differences in their biochemistry. This highlights the importance of careful characterization of relevant disease pathways to assess the suitability of cell lines, such as SH-SY5Y cells, for modelling PD or other diseases, i.e. when using the same cell line but different differentiation states.

关键词： Substrate-binding protein   Isotitration calorimetry   Homology modelling   D-methionine uptake   Molybdate   tungstate uptake  

摘要： The human gastric pathogen Helicobacter pylori relies on the uptake of host-provided nutrients for its proliferation and pathogenicity. ABC transporters that mediate import of small molecules into the cytoplasm of H. pylori employ their cognate periplasmic substrate-binding proteins (SBPs) for ligand capture in the periplasm. The genome of the mouse-adapted strain SS1 of H. pylori encodes eight ABC transporter-associated SBPs, but little is known about their specificity or structure. In this study, we demonstrated that the SBP annotated as ModA binds molybdate (MoO42?, KD = 3.8 nM) and tungstate (WO42 , KD = 7.8 nM). In addition, we showed that MetQ binds D-methionine (KD = 9.5 ?M), but not L-methionine, which suggests the existence of as yet unknown pathway for L-methionine uptake. Homology modelling has led to identification of the ligand-binding residues.

关键词： Prostate cancer   Prostatectomy   Recurrence  

摘要： Background: To validate the prognostic utility of the novel European Urology Association (EAU) biochemical recurrence (BCR) risk groups in an Asian cohort and to determine whether refinement is necessary. Methods: Two cohorts of men who experienced BCR after radical prostatectomy between 1998 and 2014 were employed. The Cox model was used to validate and model the probability of metastasis and death after BCR. Data from 817 men from the first cohort were used to develop a modified model and external validation was performed on 344 men from the second cohort. Results: Distant metastasis-free survival and cancer-specific survival from the time of BCR were significantly higher in patients with a low EAU BCR risk (prostate-specific antigen doubling time [PSADT] >1 year and pathologic Gleason score [pGS] <= 7) than in high EAU BCR risk patients (PSADT <= 1 year or pGS 8-10). In the high EAU BCR risk group, survival outcomes and efficacy of early salvage radiotherapy in patients with PSADT 6-12 months and pGS <= 7 were similar to those in the low EAU BCR risk group. The C-index, which predicts metastatic progression and cancer-specific death, improved after PSADT cutoff point was modified to 6 months, and was validated externally. Conclusion: EAU BCR risk stratification reliably identified patients at increased risk of metastasis and cancer-specific mortality in the present cohort. Modification of the PSADT cutoff point may help to optimize the predictive performance and utility of the EAU BCR risk groups in clinical practice. (C) 2021 Elsevier Inc. All rights reserved.

关键词： Candida auris   Identification   Assimilation   API ID 32 C   Susceptibility  

摘要： Background Candida auris is an emerging pathogen associated with outbreaks in clinical settings. Isolates of the pathogen have been geographically clustered into four clades with high intra-clade clonality. Pathogenicity varies among the clades, highlighting the importance of understanding these differences. Objectives To examine the physiological and biochemical properties of each clade of C. auris to improve our understanding of the fungus. Methods Optimal growth temperatures of four strains from three clades, East Asia, South Asia and South Africa, were explored. Moreover, assimilation and antifungal susceptibility properties of 22 C. auris strains from the three clades were studied. Results The optimal growth temperatures of all strains were 35-37 degrees C. Assimilation testing demonstrated that the commercial API ID 32 C system can be used to reliably identify C. auris based on the biochemical properties of the yeast. Notably, C. auris can be uniquely differentiated from commonly clinical fungi by its ability to assimilate raffinose and inability to utilize D-xylose, suggesting a useful simple screening tool. The antifungal susceptibility results revealed that all strains are resistant against fluconazole (minimal inhibitory concentration (MIC) 4 to > 64 mu g/mL) and miconazole (MIC 8 to > 16 mu g/mL), with strains from the Japanese lineage showing relatively lower MIC values (1-4 mu g/mL). Conversely, itraconazole, voriconazole, amphotericin B, micafungin and caspofungin were active against most of the tested strains. On the clade level, East Asian strains generally showed lower MICs against azoles comparing to the other clades, while they displayed MICs against flucytosine higher than those of strains from South Africa and South Asia clades. Conclusion Our data suggest a simple identification approach of C. auris based on its physiological and biochemical properties and highlight aspects of C. auris population from various clades.

关键词： Atrazine   Azoxystrobin   Fish   Imidacloprid   Monitoring   Oxidative damage  

摘要： The high demand for food consequently increases the entry of agricultural residues into water resources, and this phenomenon can affect non-target organisms in different ways. Environmentally relevant pesticide effects (per se or in combinations) are scarce in the scientific literature. Therefore, the aim of this study was to investigate: (1) the presence of pesticide residues in an important Brazilian source of water supply and power generation (Jacui river), during 1 year of monitoring. (2) in a laboratory study verify the effects of the most frequently, herbicide, fungicide, and insecticide found in Jacui river (individualized or in a mixture) on biochemical parameters in different tissues of Oreochromis niloticus. Twenty pesticide residues were detected in superficial water samples, and two of them are banned in Brazilian territory. Atrazine (0.56 mu g L-1), azoxystrobin (0.024 mu g L-1), and imidacloprid (0.11 mu g L-1) were the most frequently herbicide, fungicide, and insecticide, respectively, found in the river and were used in the laboratory assay. O. niloticus exposed to the pesticide mixture exhibited more biochemical effects than individualized exposure groups. This response can be a result of the combined pesticide effects, culminating in an additive or synergistic effect, depending on the biomarker. In individual exposure groups, atrazine presented the most pronounced alterations, followed by azoxystrobin and imidacloprid. Overall, pesticide exposure increased levels of oxidative stress parameters, reduced antioxidant enzyme activities, and induced acetylcholinesterase activity. These findings highlight the threat to aquatic organisms which may be exposed to a miscellaneous of toxic compounds in the environment.