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关键词： Cytotoxicity   Venom apparatus   Epithelium   Hypanus dipterurus   Stingray  

摘要： Ocean organisms live in competitive environments that demand the production of poisons and toxins. In some cases, these substances have been used in the pharmaceutical industry for human disease treatments. Most fish poisons generally have potent cytolytic activity, probably through cardiovascular and neuromuscular effects. In the case of marine stingrays, the injuries made by their tail venom apparatus are caused by the mechanical penetration of their sting and a subsequent venom release. This study focused on the evaluation of substances with cytotoxic activity in the epithelium that covers the venom apparatus from the marine stingray Hypanus dipterurus. To demonstrate the above, the hemolytic, proteolytic and cytotoxic capacities of H. dipterurus epithelium substances were determined. Discs impregnated with epithelial extract were used on blood agar plates. The proteolytic activity was analyzed using casein as substrate and for gelatin the liquefaction activity test. To determine the cytotoxicity degree of the extracts, the proliferation and cell viability MTT bioassay was implemented on human cervical carcinoma cells (HeLa). The results showed that no hemolytic or proteolytic activity existed against casein associated with the epithelial extract, but gelatin hydrolysis and cytotoxic activity against the HeLa cell line were observed. This study concludes that the substances found in the epithelium covering the H. dipterurus stingray venom apparatus are a mixture of various proteins, among which, glycosylated anionic proteins represent a potential source of molecules with cytotoxic and hydrolytic activity.

关键词： Moringa oleifera   Moringaceae   PGPR   Carotenoids   Tocopherols   Folate   gamma-TMT   PSY   PDS   LBC   DHFR-TS  

摘要： Plant Growth Promoting Rhizobacteria (PGPR) were utilized to contemplate their impact on the foliage of Moringa oleifera and examined for changes in tocopherols, chlorophyll, carotenoids, and folate in the sixth week. Among the eight treatments, Bacillus subtilis GB03, B. pumilus SE34, B. pumilus T4, and Pseudomonas fluorescens UOM14 improved alpha-tocopherol (10-14 fold) and beta-carotene (1-1.40 fold) altogether significantly (P <= 0.05). The most significant improvement in folate content was apparent for B. subtilis IN937B (5.47 fold) trailed by B. pumilus SE34 (5.05 fold) and B. pumilus T4 (5.12 fold) treatments. P. fluorescens UOM14 indicated remarkable improvement in Chl a (0.39 fold) and Chl b (0.44 fold) content. Organisms showing a significant increase for the analyzed molecules in individual treatment were blended in different combinations and were used for the next set of treatments. Of all the three combinations, Combination 2 (COM2-B. pumilus SE34 + B. pumilus T-4 + B. pumilus INR7) showed the maximum increase in alpha-tocopherol (8.46 fold) and gamma-tocopherol (8.45 fold), followed by Combination 3 (COM3-B. pumilus SE34 + B. pumilus T-4 + P. fluorescens UOM14) (5.93 and 3.65 fold). On the whole COM2 containing different strains of B. pumilus was found to enhance the targeted metabolites in foliage significantly. Real-time PCR studies were conducted for the biochemical pathway genes of the targeted molecules, including, gamma-tocopherol methyltransferase (gamma-TMT), phytoene synthase (PSY), phytoene desaturase (PDS), lycopene p cyclase (LBC) and dihydrofolate reductase thymidylate synthase (DHFR-TS). All the selected genes exhibited an up-regulation compared to control, similar to the biochemical output. Our investigation provides the strong evidence that PGPR can be viably utilized in combination to enhance the quality of the food crops.

关键词： glutamate excitotoxicity   brain metabolism   Epileptogenicity   lateralized periodic discharges   EEG   pathophysiology   Etiology   metabolic derangement   ischemia  

摘要： Highlights•Glutamate excitotoxicity may play a central role in generating LPDs. •Metabolic penumbra, beyond ischemia, triggers physiologic disarray generating LPDs. •Advanced neuroimaging and neuromonitoring intraparenchymal probing are suggested. •Temporal analysis can decipher if a physiologic trend is a cause or consequence.

关键词： biochemical markers   body mass index   inflammatory markers   pro-oxidant-antioxidant balance   reference values  

摘要： Background Reference values of biochemical markers are influenced by various parameters including age, sex, region, and lifestyle. Hence, we aimed to determine age- and BMI-specific reference intervals (RIs) for important clinical biomarkers in a healthy adult male population from northeastern Iran. This is also the first study to investigate reference values for pro-oxidant-antioxidant balance (PAB). Methods Seven hundred and twenty (720) healthy men, aged 20-60 years, were recruited from Sarakhs in the northeast region of Iran. Reference values for lipid profiles (total cholesterol, triglyceride, HDL-C and LDL-C), fasting blood glucose, inflammatory factors (hs-CRP and PAB), minerals (zinc and copper), uric acid, and blood pressure were measured and statistically analyzed to establish accurate age- and BMI-specific RIs in alignment with CLSI Ep28-A3 guidelines. Results RIs for lipid profiles, inflammatory factors, minerals, and uric acid required no age partitioning with the exception of fasting blood glucose and blood pressure, which demonstrated significantly higher values in subjects aged 50 years and older. Among these biomarkers, only uric acid, blood pressure, and triglycerides demonstrated statistically significant increases in reference value concentrations with increasing BMI. Conclusion In this study, age- and BMI-specific RIs for several biochemical markers were determined in healthy adult Iranian men. Partitioning by age and BMI was only required for a few analytes with most demonstrating no statistically significant changes with these covariates. These data can be useful to monitor various diseases in male adults with varying BMI in this region and others.

关键词： A   c(i)curve   C(4)photosynthesis   C(4)subtype   elevated CO2   pre-industrial CO2   stomatal conductance   V-max   V-pmax   water-use efficiency  

摘要： Leaf CO(2)uptake (A) in C(4)photosynthesis is limited by the maximum apparent rate of PEPc carboxylation (V-pmax) at low intercellular [CO2] (c(i)) with a sharp transition to ac(i)-saturated rate (V-max) due to co-limitation by ribulose-1:5-bisphosphate carboxylase/oxygenase (Rubisco) and regeneration of PEP. The response ofAtoc(i)has been widely used to determine these two parameters.V(max)andV(pmax)depend on different enzymes but draw on a shared pool of leaf resources, such that resource distribution is optimized, andAmaximized, whenV(max)andV(pmax)are co-limiting. We collected publishedA/c(i)curves in 49 C(4)species and assessed variation in photosynthetic traits between phylogenetic groups, and as a function of atmospheric [CO2]. The balance ofV(max)-V(pmax)varied among evolutionary lineages and C(4)subtypes. OperatingAwas stronglyV(max)-limited, such that re-allocation of resources fromV(pmax)towardsV(max)was predicted to improveAby 12% in C(4)crops. This would not require additional inputs but rather altered partitioning of existing leaf nutrients, resulting in increased water and nutrient-use efficiency. Optimal partitioning was achieved only in plants grown at pre-industrial atmospheric [CO2], suggesting C(4)crops have not adjusted to the rapid increase in atmospheric [CO2] of the past few decades.

关键词： Storage quality   Lipase   LOX   Comprehensive acid value   Comprehensive peroxide value   Rancidity matrix  

摘要： Millets are known for its nutritional excellence because of its high nutrient density. Among all the millets, pearl millet is considered the most important nutricereals, having 3-8% lipids. Rancidity or off-odour development in flour is one of the major limiting factors in the popularization of pearl millet all over the world. In the present investigation, we have evaluated the flour (freshly milled and 10 days after milling) of diverse genotypes of pearl millet for their hydrolytic and oxidative degradation of lipids using different biochemical parameters such as comprehensive acid value (CAV: the number of milligrammes of potassium hydroxide required to neutralize the free fatty acids present in 1 g of flour), comprehensive peroxide value (CPV: determination of the primary oxidation product i.e. hydroperoxides in the flour) and activities of lipase and lipoxygenase (LOX). We have classified pearl millet genotypes into low, medium and high rancid groups and developed a rancidity matrix (RM) with 3 groups and 6 classes;the matrix was validated using 93 diverse pearl millet genotypes. RM will be of great help to the pearl millet breeders for developing low rancid pearl millet lines.

关键词： recombinant chymosin from maral   milk-clotting activity   proteolytic activity   thermal stability   pH   calcium chloride concentration   cheese-making  

摘要： The paper reports on the production of the maral recombinant chymosin in the Escherichia coli expression system (SHaffle express strain) and the study of its biochemical properties relevant for the cheese-making industry. The highest maral recombinant prochymosin content in inclusion bodies was observed when producer cells were cultured at 25 degrees C for 6 h after the introduction of an inducer, 10 mM isopropyl-beta-D-1-thiogalactopyranoside. The biochemical properties of the obtained enzyme were compared with those of bovine and dromedarian recombinant chymosins. It is shown that total proteolytic activity of the maral recombinant chymosin was comparable with that of the bovine enzyme and that it exceeded the activity of the dromedarian enzyme by about 3.8 times. The thermal stability of the recombinant chymosin from maral was found to be 5-10 degrees C higher than that of the chymosins from the cow and dromedary. The patterns of dependence of milk-clotting activity on the pH level and calcium chloride concentration in cow's milk on the enzyme from maral met the requirements set by the cheese industry. Its high proteolytic activity and thermal stability limits the scope of application of maral recombinant chymosin to the production of cheeses with short ripening and short storage times.

关键词： Sweet marjoram   Sheep   Growth   Carcass characteristics   Metabolomics  

摘要： This study examined the effects of Origanum majorana leaf (OML) on the growth, carcass parameters and blood factors in fattening lambs. Twenty-four Kermani male lambs (initial body weight of 26 +/- 0.8 kg and seven-month-old) were assigned to three dietary treatments including one control diet (OML0), and two diets containing 2 and 4 % OML (OML2 and OML4) on the dry matter basis. The diets were fed as total mixed rations for 14 weeks. At the end of the feeding period, jugular blood samples were collected and the lambs slaughtered following an overnight fast, and the carcasses dissected. The DMI was not different between treatments, but the daily weight gain, final weight and empty body weight were higher (P < 0.05) for the diets containing 2 and 4 % OML than the OML0 diet. The warm and cold carcasses were heavier (P < 0.05), and conversion ratio (CR) was higher for the lambs fed by OML4 diet. Statistically significant differences were found between three groups regarding lean meat, testis weight and back fat. Concentrations of total serum protein, serum glutamic oxaloacetic transaminase (SGOT) and testosterone were higher, but serum triglyceride (TG) levels were lower in lambs that received OML in their diets (P < 0.05). Serum glucose, creatinine, cholesterol and urea concentrations were not influenced by the inclusion of OML to the diet. The results showed that inclusion of OML powder at a concentration of 4 % in the diet had significant positive impacts on the final weight, and improved the CR and average daily gain, and decreased serum triglyceride levels.

关键词： Non-steroidal anti-inflammatory drug   Products of transformation   Root system structure   Oxidative stress   Antioxidant defence  

摘要： Non-steroidal anti-inflammatory drugs as an important group of emerging environmental contaminants in irrigation water and soils can influence biochemical and physiological processes essential for growth and development in plants as non-target organisms. Plants are able to take up, transport, transform, and accumulate drugs in the roots. Root biomass in ten-days old pea plants was lowered by 6% already under 0.1 mg/L naproxen (NPX) due to a lowered number of lateral roots, although 0.5 mg/L NPX stimulated the total root length by 30% as against control. Higher section area (by 40%) in root tip, area of xylem (by 150%) or stele-to-section ratio (by 10%) in zone of maturation, and lower section area in zone of lateral roots (by 18%) prove the changes in primary root anatomy and its earlier differentiation at 10 mg/L NPX. Accumulated NPX (up to 10 mu g/g DW at 10 mg/L) and products of its metabolization in roots increased the amounts of hydrogen peroxide (by 33%), and superoxide (by 62%), which was reflected in elevated lipid peroxidation (by 32%), disruption of membrane integrity (by 89%) and lowering both oxidoreductase and dehydrogenase activities (by up to 40%). Elevated antioxidant capacity (SOD, APX, and other molecules) under low treatments decreased at 10 mg/L NPX (both by approx. 30%). Naproxen was proved to cause changes at both cellular and tissue levels in roots, which was also reflected in their anatomy and morphology. Higher environmental loading through drugs thus can influence even the root function. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Chrysanthemum x grandiflorum   ISSR   Metabolites   Mutagenesis   Nanotechnology   RAPD  

摘要： Despite the tremendous progress in breeding, novel and user-friendly techniques of plant improvement are desirable. The study aimed to analyze the usefulness of silver nanoparticles (AgNPs) in the breeding of chrysanthemum: one of the top ornamental plant species. In vitro regeneration of adventitious shoots from internodes of chrysanthemum 'Lilac Wonder' was induced on the modified Murashige and Skoog (MS) medium supplemented with 0.6 mg L(-1)6-benzylaminopurine (BAP), 2 mg L(-1)indole-3-acetic acid (IAA) and AgNPs at 0, 5, 10 and 20 ppm concentration. The efficiency of callogenesis and caulogenesis were analyzed after 10 weeks of culture. The concentration of chlorophylls, carotenoids, and phenolic compounds in shoots and calli were estimated. Plants obtained from 20 ppm AgNPs treatment were additionally analyzed on the genetic level using randomly amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) markers. In vitro rooted shoots were acclimatized in the glasshouse and subjected to biochemical and phenotype stability evaluation. AgNPs at the highest concentration (20 ppm) suppressed both callogenesis and caulogenesis in vitro. The concentration of metabolites in callus was stable, regardless of AgNPs treatment, except for carotenoids which production was enhanced by 20 ppm AgNPs. In contrast, the content of chlorophyllaandbin shoots varied depending on AgNPs treatment. Polymorphiclociwere detected in 12 and 9 AgNPs-treated-plants by RAPD and ISSR markers, respectively (one of which was common to both marker systems). Rooting and acclimatization were fully successful in all experimental combinations. Phenotype alternations were detected in six plants;one from 10 ppm AgNPs treatment and five from 20 ppm treatment. They included variation in pigment content (anthocyanins and carotenoids) and/or inflorescence shape. Interestingly, only two plants revealed both genetic and phenotype polymorphisms. No genetic or phenotype variation was detected in