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关键词： Ascorbic acid   Biochemical parameters   Salicylic acid   Thiamine   SALICYLIC-ACID   SODIUM-NITROPRUSSIDE   PETAL SENESCENCE   ASCORBIC-ACID   CUT   PEROXIDASE   FLOWERS  

摘要： The study was conducted to investigate the correlation between vase life and biochemical parameters in sunflower. The experiment was arranged in a randomized complete block design with five replications. Plants were sprayed by 50/100 mg L-1 salicylic acid, 50/100 mg L-1 thiamine, 100/200 mg L-1 ascorbic acid, and distilled water as control group at the eight-leaf stage. After one month, the spray treatments were repeated. The effects of preharvest spray treatment on vase life, protein, lipid peroxidation, peroxidase, polyphenol oxidase, and catalase were investigated. The result showed that thiamine by the most prolonged vase life was the most effective treatment at 50 mg L-1 with 25 days. Its vase life was more than twice the vase life of the control treatment. Also, the application of both concentrations of salicylic acid, ascorbic acid, and thiamine increased the amount of protein content, catalase, and peroxidase activity, and decreased polyphenol oxidase activity and lipid peroxidation among petals and leaves. Besides, while the vase life exhibited a positive correlation with peroxidase, catalase, and protein activity, it showed a negative correlation with polyphenol oxidase and lipid peroxidation.

关键词： Triacylglycerol   Biodiesel   Alkaline pH   Auxenochlorella protothecoides   Nitrogen starvation   MICROALGAE CHLORELLA-PROTOTHECOIDES   LIPID PRODUCTION   BIODIESEL PRODUCTION   HETEROTROPHIC CULTIVATION   ACCUMULATION   BIOMASS   CARBON   PRODUCTIVITY   DEPRIVATION   FEEDSTOCKS  

摘要： Microalgae can accumulate substantial amounts of triacylglycerol, the primary feedstock for biodiesel production, under different stress conditions. In this study, exposure to alkaline pH (pH 10) using carbonate-bicarbonate buffer, nitrogen starvation, and both were applied to induce triacylglycerol accumulation in Auxenochlorella protothecoides KP7. In addition to triacylglycerol accumulation, growth, biochemical composition, and fatty acid profiles were examined in detail and compared. Our results illustrated that the combination of nitrogen starvation and alkaline pH led to significant increases in triacylglycerol and starch contents and drastic decreases in chlorophyll and protein contents compared with their control levels. Triacylglycerol levels, the triacylglycerol/total lipid ratio, and lipid productivities were significantly increased after 7 days of cultivation under the combined stress compared with the effects of nitrogen starvation alone. After prolonged cultivation under the combined stress, triacylglycerol content reached up to 25.01% of the dry cell weight and constituted up to 81.25% of total lipids. Under the combined stress, the major fatty acids in the total lipid of A. protothecoides KP7 were C18:1 (57.5%), C18:2 (19.5%), C16:0 (12.5%), and C18:3 (5.6%), and the percentages of saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids represented 16.3, 58.4, and 25.1% of the total fatty acids, respectively. Furthermore, the combined stress was associated with the lowest iodine value (97.64 g I-2 (100 g)(-1)), highest oxidative stability (7.29 h), and highest cetane number (55.26) among the examined conditions. The use of nitrogen-free medium containing carbonate-bicarbonate buffer for cultivation appears promising for enhancing triacylglycerol production in A. protothecoides.

关键词： SAGA   Coactivator complex   Transcription   Histone acetylation   Ubiquitination   TBP   TATA-BINDING-PROTEIN   RNA-POLYMERASE-II   HISTONE ACETYLTRANSFERASE ACTIVITY   TRANSCRIPTION ELONGATION-FACTOR   TRANSPOSABLE ELEMENT TY1   IMMEDIATE-EARLY PROTEIN   IN-VIVO TARGET   SACCHAROMYCES-CEREVISIAE   NUCLEOSOME ACETYLATION   H2B UBIQUITYLATION  

摘要： One of the major advances in our understanding of gene regulation in eukaryotes was the discovery of factors that regulate transcription by controlling chromatin structure. Prominent among these discoveries was the demonstration that Gcn5 is a histone acetyltransferase, establishing a direct connection between transcriptional activation and histone acetylation. This breakthrough was soon followed by the purification of a protein complex that contains Gcn5, the SAGA complex. In this article, we review the early genetic and biochemical experiments that led to the discovery of SAGA and the elucidation of its multiple activities.

关键词： Ga-68-PSMA   PET   CT   Prostate cancer   Tumor burden   I-AND-T   GA-68-PSMA PET/CT   RADICAL PROSTATECTOMY   PSA  

摘要： Purpose The objective of this study was to evaluate whether(68)Ga-PSMA PET/CT whole-body tumor burden (PSMAwbtb) is associated with clinical parameters and laboratory parameters in prostate cancer patients. Methods We retrospectively evaluated prostate cancer patients submitted to PSMA PET/CT for primary staging purposes or due to biochemical recurrence (BR).PSMAwbtbmetrics (total volume of PSMA-avid tumor (PSMA-TV)) and total uptake of PSMA-avid lesions (PSMA-TL) were calculated semi-automatically. Spearman's rank correlations betweenPSMAwbtbmetrics and clinical, laboratory parameters (age, time-to-BR, years of diagnosis of prostate cancer, free and total serum PSA levels, and the Gleason score) and with the highest SUVmax of a lesion (hSUVmax) were analyzed. Results Among the 257 PSMA PET/CT studies, there were 46 scans (17.9%) performed for primary staging and 211 (82.1%) for BR. PSMA-TV and PSMA-TL were calculated for the 157 positive scans (58.8%), which were 43 patients (93.5%) in the primary staging group and 114 patients (54.0%) in the BR group. In the primary staging group, we observed a significant correlation between PSMA-TL andhSUVmax (p = 0.0021). In the BR group, there was a significant direct correlation between PSMA-TL and the variables age (p = 0.0031), total serum PSA values (p = < 0.0001), free serum PSA values (p = < 0.0001), and thehSUVmax (p = < 0.0001). Similar results were obtained for PSMA-TV. Conclusion PSMAwbtbhas a direct and positive correlation with serum PSA values and age in prostate cancer patients with BR.

关键词： invasive species   water stress   nutrient use   biomarkers   seedling growth   cerrado   INVADER C-4 GRASSES   MELINIS-MINUTIFLORA   OXIDATIVE STRESS   SUPEROXIDE-DISMUTASE   LIPID-PEROXIDATION   BRAZILIAN SAVANNAS   RESPONSES   GROWTH   FLUORESCENCE   FIRE  

摘要： The cerrado is a Neotropical savanna characterized by a soil and vegetation mosaic where plants endure dystrophic soils and seasonal drought. Dry spells or flooding are the main environmental stress native species face in their growth period. African grasses are common invasive species, jeopardizing the biodiversity by displacing native species and outgrowing them. Invasive species may benefit from human interventions that increase nutrient availability in natural areas and may respond differently than natives to environmental conditions. Therefore, we compared the performance of one native (Schizachyrium microstachyum) and one invasive (Melinis minutiflora) grass in different conditions of water and nutrient availability simulating possible cerrado scenarios. Five-week-old seedlings were submitted to different irrigation treatments (simulating dry spells, normal rainfall, and flooding) and fertilization treatments (high or low nutrient availability) for four weeks, and were analyzed for morphological (leaf area, length of the shoot, number of tillers, seedling dry weight, and root:shoot ratio) and physiological parameters (chlorophyll fluorescence, pigment concentration, nutrient content, and biochemical assays). There was a trend for the invasive species to show better responses to water stress by growing more profusely, showing an even higher effect when the soil was richer in nutrients. The invasive species may outcompete the native species by using nutrients and water more efficiently, showing a weaker oxidative response to drought and fertilization. The native species would perform at a similar pace to the invasive species in conditions of less water and nutrient availability, whereas unnatural fertilization inputs and high-water availability would benefit the invasive species.

关键词： In vitro stress   Long-term cultures   Antioxidant defense proteins   Dead cell analysis   NUCLEAR-DNA CONTENT   EMBRYOGENESIS   L.  

摘要： Various strategies have been developed globally to conserve germplasm by propagating plants. One important technique is in vitro propagation and preservation through tissue culture. In many investigated plants, the long in vitro conservation is plagued with several limitations like genetic variations, developmental errors in cells or tissues due to induced stress. This provoked us to conduct a study of Catharanthus roseus culture maintained for over fourteen long years and a newly established 8-month-old culture. The present study investigated and compared the two tissue types differing by their age. The biomass accumulation, the biochemical differences of the two, dead cell analysis with aging via confocal microscopy, and liquid chromatography-mass spectroscopy (LC-MS)-based proteomic differences were studied in old and newly established Catharanthus culture. The proteomic study reveals more than 120 upregulated or high abundance proteins in old culture as compared to newly established Catharanthus. The identified upregulated proteins are stress protein 69, heat shock proteins (HSP), isocitrate dehydrogenase, pyruvate dehydrogenase, and others. These proteins had an association with antioxidant activities, related to stress, and a few are linked to respiration. Our study reveals the presence of a robust antioxidant defense mechanism, i.e., 51.94%, 78.8%, and 61% higher SOD, APX, and CAT activities in older cultures (O) as compared to newly established tissues (N), which perhaps act against stress and may play a key role in ameliorating negative impacts of long-term in vitro conditions. The inherent strong antioxidant defense system in old cultures added resilience and enabled the culture to revive growth quickly (within 1-2 days) following transfer to new medium as compared to new culture (7-10 days). The biomass accumulation was more (37.08 %) in old tissues as compared to new culture. The 2C DNA or genome size of C. roseus especially the 14-year-old culture-deriv

关键词： Maize   Rhizosphere   Ion dynamics   Nutrient physiology   Morpho-physio-biochemical attributes   Cd tolerance  

摘要： Cadmium (Cd) in soil-plant system can abridge plant growth by initiating alterations in root zones. Hydroponics and rhizoboxes are useful techniques to monitor plant responses against various natural and/or induced metal stresses. However, soil based studies are considered more appropriate in order to devise efficient food safety and remediation strategies. The present research evaluated the Cd-mediated variations in elemental dynamics of rhizospheric soil together with in planta ionomics and morpho-physio-biochemical traits of two differentially Cd responsive maize cultivars. Cd-sensitive (31P41) and Cd-tolerant (3062) cultivars were grown in pots filled with 0, 20, 40, 60 and 80 mu g/kg CdCl2 supplemented soil. The results depicted that the maize cultivars significantly influenced the elemental dynamics of rhizosphere as well as in planta mineral accumulation under applied Cd stress. The uptake and translocation of N, P, K, Ca, Mg, Zn and Fe from rhizosphere and root cell sap was significantly higher in Cd stressed cv. 3062 as compared to cv. 31P41. In sensitive cultivar (31P41), Cd toxicity resulted in significantly prominent reduction of biomass, leaf area, chlorophyll, carotenoids, protein contents as well as catalase activity in comparison to tolerant one (3062). Analysis of tolerance indexes (TIs) validated that cv. 3062 exhibited advantageous growth and efficient Cd tolerance due to elevated proline, phenolics and activity of antioxidative machinery as compared to cv. 31P41. The cv. 3062 exhibited 54% and 37% less Cd bio-concentration (BCF) and translocation factors (TF), respectively in comparison to cv. 31P41 under highest Cd stress regime. Lower BCF and TF designated a higher Cd stabilization by tolerant cultivar (3062) in rhizospheric zone and its potential use in future remediation plans.

关键词： Vermicompost   Larch   Soil   Chemical properties   Microbiota   Enzymes   MELOIDOGYNE-INCOGNITA   ENZYME-ACTIVITIES   GENE   PRINCIPLES  

摘要： The aim of this study was to assess the changes in chemical and microbial properties and enzymatic activity of soil enriched with vermicompost derived from household waste. The vermicompost was tested in the rhizosphere ofLarixdecidua seedlings cultivated in 10-L pots in: (i) nursery soil (as the control), (ii) soil with 10% v/v vermicompost, and (iii) with 20% v/v vermicompost. The impact of vermicompost was assessed in terms of soil C/N ratio; bacterial, fungal, and nematode counts; and enzymatic activity. It was found that vermicompost increased the C/N ratio from 21 to 32, as well as the content of nitrate from 78 to 134 mg kg(-1), of ammonium from 14 to 139 mg kg(-1), of phosphorus from 92 to 521 mg kg(-1), and of potassium from 142 to 1912 mg kg(-1), compared with the control soil. The abundance of beneficial bacteria was increased (from 8.61 x 10(7)to 37.9 x 10(7)), along with decreases in microbiological ratios of fungi and bacteria (e.g. fungi/Bacillus from 0.18818 to 0.00425). A significant 2- to 4-fold increase was observed compared with the control in the number of beneficial nematodes belonging to bacterivorous, fungivorous, and predatory groups with no change in the abundance of plant-parasitic nematodes. Addition of vermicompost brought about a change in soil enzyme activity. Vermicompost reduced the activity of alkaline phosphatase only. Both doses of vermicompost led to an increase in the activity of acid phosphatase, inorganic pyrophosphatase, dehydrogenases, beta-glucosidase, and urease. Only the higher dose had an effect on increasing the activity of o-diphenol oxidase and proteases. No significant change was observed for nitrate reductase. Also, the presence of antibiotics produced by bacteria was detected depending on the dose of vermicompost, e.g. iturin (ituC) and bacillomycin (bmyB) were found in soil with a dose of 20% v/v vermicompost. Overall, vermicompost produced from household waste can be an excellent organic fertilizer for larch fore

关键词： PROTEINS   CYSTEINE   DESIGN  

摘要： New findings on the chemistry of the amino acids, their role in protein folding, and their sequential primordial introduction have uncovered concealed causalities in genetic code evolution. The genetically encoded amino acids successively provided (i) membrane anchors, (ii) halophilic protein folds, (iii) mesophilic protein folds, (iv) metal ligation, and (v) antioxidation.