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关键词： Abscisic acid   Actinidia chinensis var. deliciosa   Elicitors   Hayward   Phytohormones   Pseudomonas syringae pv. actinidiae   tolerance  

摘要： The use of plant elicitors for controlling Pseudomonas syringae pv. actinidiae (Psa), the etiological agent of the kiwifruit bacterial canker (KBC), has been analysed in the past and, while salicylic acid (SA) seems to decrease disease susceptibility, methyl jasmonate (MJ) shows an opposite effect. However, the metabolic and genomic responses of Psa-infected plants following elicitation with these two compounds, as compared with non-elicited Psa-inoculated plants, are poorly understood, being the focus of this study. Micropropagated A. chinensis 'Hayward' plants were elicited with MJ or SA, and further inoculated with Psa. Fifteen days post-inoculation, Psa population in MJ-treated plants was increased by 7.4-fold, whereas SA elicitation led to decreased Psa colonization (0.5-fold), as compared with non-elicited inoculated plants. Additionally, elicitation with MJ or SA generally decreased polyphenols and lignin concentrations (by at least 20%) and increased total proteins (by at least 50%). MJ led to the upregulation of SOD, involved in plant antioxidant system, and reporter genes for the jasmonic acid (JA) (JIH and LOX1), abscisic acid (SnRK), SA (ICS1), and ethylene (ACAS1, ETR1 and SAM) pathways. Moreover, it increased ABA (40%) and decreased carotenoids (30%) concentrations. Contrastingly, comparing with non-elicited Psa-inoculated plants, SA application resulted in the downregulation of antioxidant system-related genes (SOD and APX) and of reporter genes for ethylene (ETR1) and JA (JIH and ETR1). This study contributes to the understanding of potential mechanisms involved in kiwifruit plant defences against Psa, highlighting the role of the JA, ABA and ethylene in plant susceptibility to the pathogen.

关键词： Almond valorization   Fatty acids   Vitamin E   Nutritive values   Tocopherol homologues   Antioxidants  

摘要： The specific approach of any fruit tree genetic resources preservation program depends undoubtedly on the valorization of the autochthonous germplasm with noticeable traits related to quality and adaptation to harsh climatic conditions. In this context, pomological and biochemical properties of 15 chance seedling almond genotypes, 11 old local Tunisian cultivars and 5 foreign introductions from different origins were studied in order to evaluate possibilities for their commercial and industrial valorization features. Parameters with high discriminating values were more related to kernel weight and width, shelling percentage, oleic and linoleic acids, tocopherols, sugar and protein contents. On the other hand, oil and protein contents were highly variable between genotypes, ranging respectively from 42.6 to 61 % and from 14.5 to 28.3 % of the total kernel dry weight. Main fatty acids ranged between 5.9-7.5 % for palmitic acid, 60.3-76.5 % for oleic acid, and 13.4-28.9 % for linoleic acid. The range of variation of tocophemls, was large for a-tocopherol (208.3-629.2 mg kg(-1) oil) and for gamma-tocopherol (2.8-21.9 mg kg(-1) oil). Although the physical performances of the kernels for some accessions were in general low, their interesting chemical composition offers the possibility of many alternative uses which could improve their marketable value. In addition, some genotypes were singled out as the most promising for varied commercial finalities. 'Porto' and 'Blanco' were characterized by high stable total sugar and sucrose contents. Moreover, 'Blanco' had the highest alpha-, gamma- and delta-tocopherol contents. 'Guernghzer, 'Ras Bouma' and 'Forme en Poire' were a rich source of protein while 'Mahsouna' and 'Achaak' may be a potential source for almond oil extraction. All of the understudied '*** Bouchouka' and 'Forme en Poire' oils had powerful antioxidant effects due to their high alpha-tocopheml content. 'Sahnoun' and 'Zahaaf presented valuable oil with high

关键词： Antioxidant   Moisture stress   Moringa   Phenolics   Proline   ANTIOXIDANT ACTIVITY   SECONDARY METABOLITES   PROLINE BIOSYNTHESIS   DIFFERENT PARTS   STRESS   DROUGHT   ACCUMULATION   PHENOLICS   ANTIBACTERIAL   CAPACITY  

摘要： Continual water loss through transpiration and evaporation as a result of drought leads to stomatal closure and subsequently the overproduction of reactive oxygen species (ROS) which causes oxidative stress in plants. A set of biochemical mechanisms are concurrently triggered to set in motion a defence line, which, among others, involves the synthesis of antioxidant and osmoprotectants compounds. These play a protective role to overcome stress. The objective of this study was to evaluate the effect of varying moisture regimes on the accumulation patterns and concentration of phenolic compounds, antioxidant activity and osmolyte proline in Moringa oleifera. The study was conducted in a greenhouse (25 +/- 3 degrees C) at ARC, Roodeplaat in Pretoria, South Africa. Moringa oleifera seeds were individually planted in pots using hygro-mix as the growth media. The experiment was laid out in a completely randomised design with four watering regimes of 100%, 75%, 50% and 35% field water capacity (FWC) each with 50 replicate plants. Proline content increased with the severity of moisture stress in all plant parts (root, stem and leaf), with the leaves under severe stress (35% FWC) recording the highest concentration. Folin C, aluminium chloride and butanol-HCL assays were used to determine total phenolic, flavonoid and condensed tannin concentrations, respectively, in the different plant parts at different growth stages and harvests. The concentrations of these secondary metabolites were consistently higher in leaves and increased with an increase in moisture stress. The highest concentrations were recorded in the second harvest under severe stress (35% FWC) for total phenolics and proanthocyanidins at 50% FWC for flavonoids. Leaves showed a better antioxidant ability and antioxidant activities increased with drought progression as determined by FRAP while DPPH radical scavenging and the b-carotene-linoleic acid model system did not show a distinct trend in antioxidant activi

关键词： Amide   Disulphide bonds   MMP-8   Non-smoker   Protein   Raman spectroscopy   Saliva   Smoker   MUCINS  

摘要： The study aim was to investigate the potential of salivary biochemical assessments to determine smoking cessation in patients under smoking cessation programs. The study validated smoking behavior and degree of nicotine dependence using Fagerstro center dot m test for nicotine dependence in smokers and non-smokers. Protein components were examined using Raman spectroscopy. Salivary matrix metalloproteinases-8 (MMP-8) levels were analyzed using Quantikine human total MMP-8 immunoassay-kits. Thiocyanate (SCN-) concentrations, peroxidase and glutathione-peroxidase activities were determined using spectrophotometric methods. Human mononuclear cell line was examined for M1 polarization. The data were analyzed using Fisher's exact test and twotailed paired t-test at alpha = 0.05. Amide I peak in smoker group was significantly reduced as compared to nonsmokers (p < 0.05). Sulfhydryl bond, dialkyl disulfides SS-stretch and corresponding disulphide bond at 500-545 cm-1 were significantly increased in smokers (p < 0.05). The CH2 wag showed higher intensity amongst smoker group representing a recoil of carbon atoms. Salivary MMP-8 levels of participants after smoking cessation was significantly lower than smoking salivary levels (p < 0.05). The SCN- and peroxidase concentrations were significantly higher in smoking group whereas an M1 polarization was seen in non-smokers. Salivary biochemical analysis can aid clinicians to verify smoking cessation in patients under smoking cessation programs.

关键词： Water quality parameters   Prediction   Hydrometeorological variables   Tropical environment   WATER-QUALITY INDEX   VECTOR AUTOREGRESSION   MODEL   FORECAST   EVALUATE   PAHANG  

摘要： In this research, three water quality (WQ) indexes, namely dissolved oxygen (DO), biochemical oxygen demand (BOD), and chemical oxygen demand (COD), in Selangor River of peninsular Malaysia were simulated using a stochastic model based on vector autoregression (VAR). The simulation was adopted based on three modeling scenarios of inputs as predictor: (i) related WQ parameters, (ii) WQ parameters and river flow data, and (iii) WQ parameters and rainfall data. The WQ parameters as input were determined based on the correlation analysis. The numerical analyses revealed that the prediction accuracy of VAR model substantially increases with the increase in input number. The model provided better accuracy in predictions of WQ indexes (root mean square error approximate to 0.11 and mean absolute error approximate to 0.26) when all environmental, hydrological, and climatological variables were considered. Further improvement in model performance (root mean square error approximate to 0.0248 and mean absolute error approximate to 0.1259) can be achieved if physiochemical parameters like suspended solid material and the turbidity are used as additional inputs.

关键词： Midazolam   Palliative   Renal impairment   GFR   MDRD   LOO   Validation  

摘要： Rationale & objective: Midazolam is one of top three drugs used in palliative care. Its use increases in the last days of hospice patients' lives while safe dosage can be challenging. Equations currently used to estimate glomerular filtration rate, e.g: the Cockroft-Gault (eGFR(CR)) and the Modification of Diet in Renal Disease (eGFR(MDRD)) ones, do not generate precise calculations, especially in palliative patients exhibiting variations in body parameters. Our aim was to seek new relationships between mean midazolam (M-avg) and alfahydroxymidazolam (OH-M-avg) concentrations in plasma, and selected biochemical and physiological parameters of palliative patients, to enable optimal midazolam pharmacotherapy. Study design, participants and interventions: The pilot study included 11 Caucasians, aged 42-95, with advanced cancer disease, receiving midazolam in a hospice in-patient unit. We tested correlations among M-avg, BMI, eGFRMDRD, midazolam clearance (CL), OH-M-avg, bilirubin (Bil) and blood creatinine concentration (Cr). F test and leave-one out (LOO) validation was applied to verify the correlations' significance and predictive ability. Results: We found ten statistically significant (p < 0.05) correlations related to midazolam pharmacokinetics and physiological factors. We formulated two equations with high degree of predictive ability, based on the eGFR(MDRD)-> CL and the (Bil + BMI x Ln(Cr))-> M-avg-(OH-M-avg) correlations. The limitations of the study mainly revolve around its pilot nature and the need to continue testing the results on a bigger population. No funding to disclose. Conclusions: The significance of correlations corresponding to the arithmetic expressions confirms that Bil, BMI, Ln(Cr) analyzed simultaneously report a series of processes on which midazolam metabolism depends. Two of ten correlations proposed came close to meet all LOO validation criteria. Current findings can help optimize midazolam treatment in palliative therapy.

关键词： Aripiprazole   Polymeric microparticles   Long acting parenteral   Schizophrenia   Behavioural activity   Biochemical   OXIDATIVE STRESS   NEGATIVE SYMPTOMS   RELEASE   MODEL   MICROSPHERES   MECHANISMS   PROTEINS   BRAIN   DRUG   RATS  

摘要： Schizophrenia is a neurodevelopmental disorder which is expressed in the form of disturbed behaviour and abnormal mental functions. Patient's non-adherence to the medicine is the main cause of failure of drug therapy and increases incidence of relapses. Thus, for successful management of disease long acting parenteral formulations were developed. Aripiprazole was encapsulated in biocompatible polycaprolactone microsphere by o/w emulsion solvent-evaporation method in order to achieve sustained release of the drug for several weeks after single subcutaneous administration. They were optimised on the basis of various parameters such as physical appearance, particle size (49.4 mm-387.1 mm), encapsulation efficiency (70%-95%), percentage yield (33%-75%) and drug loading (25.9%-47.5%). The surface topography and sphericity of the microspheres was determined by scanning electron microscopy which revealed that the microspheres formed were spherical and non-porous in nature. The in vitro releases from the selected formulations were found to be 87% and 95% respectively after 45 days of dissolution. In vivo efficacy of optimised formulation showed significantly (p < 0.05) amelioration of various positive, negative and cognitive symptoms associated with schizophrenia and oxidative stress markers in ketamine-induced schizophrenia model in rats for 30 days. (C) 2021 American Pharmacists Association?. Published by Elsevier Inc. All rights reserved.

关键词： 植物生物化学  

ISBN: (纸本)9787030672001

关键词： Free amino acids   Heat stress   Maguey   Plant growth   Seed provenance   Soluble sugars   HEAT-STRESS   AMINO-ACIDS   METABOLISM   TOLERANCE   SEEDLINGS   PLANTS   PHOTOSYNTHESIS   ACCUMULATION   PRODUCTIVITY   ACCLIMATION  

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.