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关键词： Mollusk   Oxidative stress   Biocide   Biomarker   Antioxidant defence   GLUTATHIONE-S-TRANSFERASE   PAINT BOOSTER BIOCIDES   4,5-DICHLORO-2-N-OCTYL-4-ISOTHIAZOLIN-3-ONE DCOIT   SUPEROXIDE-DISMUTASE   DIGESTIVE GLAND   SEA-9 211(TM)   TOXICITY   EXPOSURE   GROWTH   BIOTRANSFORMATION  

摘要： Biological fouling is an unwanted phenomenon that results in economic losses to the shipping industry. To prevent fouling, antifouling paints are used. DCOIT (4,5- dichloro-2-n-octyl-4-isothiazolin-3-one) is a biocide present in many antifouling paint formulations, and is toxic to a wide range of organisms. The aim of the present study was to evaluate the effects of DCOIT on oxidative stress indicators of the brown mussel, Perna perna. Molecular (SOD-like, GSTO-like and MGST-like mRNA levels) and biochemical (activities of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST), and levels of glutathione (GSH), reactive oxygen species (ROS) and protein carbonyls (PCO)) components were evaluated. Further, levels of biomarkers were assessed in the gills and digestive glands of mussels. Bivalves were exposed to DCOIT (control, 0.1 mu g/L and 10 mu g/L) for up to 96 h. DCOIT exposure decreased GSH content in gills. Moreover, exposure to DCOIT also decreased CAT activity in the gills and digestive glands of mussels. GST activity increased in digestive gland after exposure for 24 h to both concentrations of DCOIT tested. SOD activity, ROS levels and PCO content were not affected by exposure to the contaminant. Regarding the molecular biomarkers evaluated, DCOIT exposure altered mRNA levels of SOD-like in both tissues after 24 and 96 h of exposure, and decreased MGST-like mRNA levels in the digestive gland after 96 h of exposure to the chemical. These findings suggested that exposure to DCOIT may alter the biochemical and molecular functioning of P. perna, which may harm the species.

关键词： Carotenoids   Proximate composition   Alpha-cypermethrin   Lipid peroxidation   Antioxidant enzymes   PHOTOOXIDATIVE STRESS   ALPHA-CYPERMETHRIN   INSECTICIDE ALPHA   CHLOROPHYLL-A   MICROALGAE   ACCUMULATION   SYSTEMS   PHOTOSYNTHESIS   BIODEGRADATION   CHLOROPLASTS  

摘要： The present study demonstrates that the environment play a vital role in the development of tolerance in the local algal isolates towardsalpha-cypermethrin. The isolates collected from rice fields (Scenedesmus ecornis NC-M9 andTetradesmus dimorphus NC-K2) showed significantly higher tolerance than the isolates collected from freshwater bodies far from the rice fields. Also, significant reduction in Malondialdehyde (MDA) content was noticed inS. ecornis NC-M9 after fourth and seventh day exposure to alpha-cypermethrin compared to first day exposure. However, the Superoxide Dismutase (SOD) and Peroxidase (POD) contents ofS. ecornis NC-M9 enhanced at 4th and 7th day exposure to alpha-cypermethrin compared to 1st day exposure. Further, biochemical studies of all isolates show that Graesiella emersonii NC-M1 (the isolate from freshwater bodies near to rice field) possesses higher contents of Chlorophylla (Chla), carotenoid and lipid (5.59 +/- 0.36 mg.L-1, 2.5 +/- 0.024 mg.L-1 and 28 +/- 2.5% Dry Cell Weight (DCW), respectively) compared to other. This variation in biochemical parameters present in different field areas as collected and tested could be further used as potential substrates for production of bioactive compounds which have many health and environmental benefits.

关键词： Meniscus   Spectroscopy   Near-infrared   Regression analysis   Biomedical technology   REFLECTANCE SPECTROSCOPY   CARTILAGE LESIONS   KNEE   QUANTIFICATION   RELIABILITY   REGRESSION   REPAIR   TEARS   RATES   SKIN  

摘要： Degenerative changes in meniscus are diagnosed during surgery by means of mechanical testing and visual evaluation. This method is qualitative and highly subjective, providing very little information on the internal state of the meniscus. Thus, there is need for novel quantitative methods that can support decision-making during arthroscopic surgery. In this study, we investigate the potential of near-infrared spectroscopy (NIRS) for mapping the biochemical constituents of human meniscus, including water, uronic acid, and hydroxyproline contents. Partial least squares regression models were developed using data from 115 measurement locations of menisci samples extracted from 7 cadavers and 11 surgery patient donors. Model performance was evaluated using an independent test set consisting of 55 measurement locations within a meniscus sample obtained from a separate cadaver. The correlation coefficient of calibration (rho(training)), test set (rho(test)), and root-mean-squared error of test set (RMSEP) were as follows:water(rho(training)= 0.61,rho(test)= 0.39, and RMSEP = 2.27 percentage points),uronic acid(rho(training)= 0.68,rho(test)= 0.69, and RMSEP = 6.09 basis points), andhydroxyproline(rho(training)= 0.84,rho(test)= 0.58, and error = 0.54 percentage points). In conclusion, the results suggest that NIRS could enable rapid arthroscopic mapping of changes in meniscus biochemical constituents, thus providing means for quantitative assessment of meniscus degeneration.

关键词： Grain yield   Heat stress   Oxidative stress   Physiological activity   Vigna unguiculata   STRESS   GROWTH   PEROXIDASE   GENOTYPES   CATALASE  

摘要： High temperature stress can hinder the development of cowpea resulting in several damages including vegetative and reproductive phases of the crop. In this context, the objective of this study was to select cowpea cultivars tolerant to high temperature stress using various parameters related to physiological, biochemical, and yield aspects. For this, the cultivars Carijo, Itaim, Pujante, Rouxinol, and Tapahium were used, maintained in two temperature regimes: 20-26-33 degrees C and 24.8-30.8-37.8 degrees C. The experiment was carried out in growth chambers, in a 5 x 2 factorial arrangement (cultivars x temperature regimes). Responses differentiated among the cultivars Carijo, Itaim, Pujante, Rouxinol, and Tapahium with the increase of 4.8 degrees C in air temperature. The high temperature promoted a greater quantity of aborted flowers, leading to a reduction in the yield of the cultivars Carijo, Pujante, Rouxinol, and Tapahium. The photosynthesis, stomatal conductance, leaf transpiration and enzymatic activities were significantly influenced by high temperature. From the combination of the responses of biometric, physiological and productive variables, the cultivar Itaim can be considered as tolerant to an increase of 4.8 degrees C in air temperature.

关键词： Biochemical compounds   Cryopreservation   Genetic stability   Rooting   Shallot   Vegetative growth   POTATO SHOOT-TIPS   DROPLET-VITRIFICATION   STABILITY   GERMPLASM   CHRYSANTHEMUM   ANTIOXIDANT   IMPROVEMENT   ONION   L.  

摘要： Key message Rooting, vegetative growth, bulb production, genetic stability and biochemical compounds were maintained in cryopreserved plants of shallot. Our results support use of cryopreservation for long-term preservation of shallot germplasm. Shallot (Allium cepa var. aggregatum), a small bulb onion, is widely grown in the world. We previously reported a droplet-vitrification for cryopreservation of in vitro-grown shoot tips of shallot genotype '10603'. The present study further evaluated rooting, vegetative growth, bulb production and contents of biochemical compounds, as well as genetic stability in cryo-derived plants. The results showed no significant differences in rooting, vegetative growth, bulb production and contents of soluble sugars and flavonols between the cryo- and in vitro-derived plants. Analyses of ISSR and AFLP markers did not detect any polymorphic bands in the cryo-derived plants. These results indicate rooting and vegetative growth ability, biochemical compounds and genetic stability were maintained in cryo-derived plants. The present study provides experimental evidences that support the use of cryopreservation method for long-term preservation of genetic resources of shallots and other Allium species.

关键词： Lithodes santolla   Air-Exposure   Live market   Meat quality   LITHODES-SANTOLLA MOLINA   NEPHROPS-NORVEGICUS L.   SHORT-TERM EMERSION   LIPID OXIDATION   PARALITHODES-CAMTSCHATICUS   FUNCTIONAL-PROPERTIES   ABDOMINAL-MUSCLE   DECAPODA ANOMURA   NORWAY LOBSTER   BEAGLE CHANNEL  

摘要： The trade of live crustacean species is a unique practice that attracts costumers by ensuring crab freshness. This seafood is consumed worldwide because of its nutritional value and positive impact on human health. However, few studies address the impact of the complex live-trade chain on the animal and meat quality parameters. We aimed to study the air-exposure and re-immersion effect on Southern King Crab (SKC) Lithodes santolla biochemical and meat quality parameters. Live SKC were air-exposed for 24 h at 8 degrees C and then re-immersed in seawater for 24, 48 and 96 h, at the same temperature. We recorded crab vigor, as well as raw and cooked meat parameters, to assess the quality after dry-transport simulation and during re-immersion. Specifically, biochemical parameters such as proximate chemical composition and lactate accumulation, and quality parameters such as total volatile basic nitrogen (TVB-N) and textural properties were assessed. We found no mortality after the air-exposure interval, with vigor values recovering after 96 h of re-immersion. Besides, the airexposure interval increased the TVB-N, as it decreased pH and moisture of cooked meat, but did not affect the meat texture or cooking yield. We conclude that air-exposure has a subtle impact on Lithodes santolla meat quality and changes are reversed after the re-immersion of crabs in recirculating seawater aquaria. Ensuring live trade quality of crustacean meat after long dry-transport allows for market expansion, since crabs can be transported to more distant regions. This would also have a positive impact on high-seas fisheries, because crab could be maintained until ships arrive ashore.

关键词： Argentina   Colubridae   Enzymes   Hemorrhage   Rear-fanged snake   Toxins   PROTEINS   DIPSADIDAE  

摘要： With the aim to widen the current knowledge of toxinological implications of bites from rear-fanged snakes and biological roles of their venoms, this study focuses on the biochemical composition and toxic effects of the venom of Leptodeira annulata pulchriceps from Argentina. We analyzed the protein composition by electro-phoresis and mass spectrometry, and enzymatic properties by quantitative assays on different substrates. Additionally, we evaluated local and systemic toxicity in mice, and tested its cross-reactivity with elapid and viperid antivenoms used in Argentina. This venom showed features reminiscent of venoms from snakes of Bothrops genus, containing components ranging from similar to 17 to 75 kDa, which are mainly tissue-damaging toxins such as proteinases. Although showing low lethality to mice (LD50 = 20 mu g/g body weight), prominent hemorrhage developed locally in mice intramuscularly and intradermally injected with the venom, and the minimum hemorrhagic dose was found to be 12.7 mu g/mouse. This study is the first comprehensive investigation of the venom of L. a. pulchriceps, and sheds new light on differences between this and those of the other two subspecies of L. annulata. Additionally, the study provides new insights into the venom components of "colubrid" snakes, advocating for considering bites from this rich diversity of snakes as a public health problem that needs to be addressed worldwide.

关键词： Liver function   Kidney function   ALAD activity   Lead   Cadmium   Mining site   BLOOD LEAD LEVELS   DELTA-AMINOLEVULINIC-ACID   OXIDATIVE STRESS   WILD RATS   ZINC MINE   CADMIUM   CHILDREN   COEXPOSURE   ACCUMULATION   INCREASES  

摘要： Lead (Pb) interferes with various bodily functions. Although high blood Pb (Pb-B) levels in residents from Kabwe, Zambia have been reported, the accumulation pattern of other metals remains unknown. The study was designed to determine the Pb-B, blood cadmium (Cd-B), and zinc (Zn-B) values of 504 representative samples from Kabwe, as well as the potential associated adverse health effects. The Pb-B level ranged from 0.79 to 154.75 mu g/dL and generally increased in areas near the mine. A significant elevation of Cd-B was observed in two areas (0.37 +/- 0.26 and 0.32 +/- 0.30 mu g/L) where the two highest mean Pb-B levels were recorded. By contrast, the Zn-B values did not differ greatly with respect to area. Some blood biochemical parameters relating to hepatic and renal functions were out of the normal range in approximately 20-50% of studied adult participants. The delta-aminolevulinic acid dehydratase (delta -ALAD) activity was significantly inhibited in the two areas contaminated by Pb and Cd. A significant negative relationship was observed between metal levels and clinical parameters, e.g., between Pb-B and delta -ALAD for all the age categories and between Cd-B and the estimated glomerular filtration rate for all the age categories except 0-4 years. The elevated Cd-B in areas near the mine relative to the other areas suggested the potential adverse health effects of Cd and/or the interaction of Pb and Cd. A significant association of metal levels with clinical parameters also indicated the effects of metal exposure on hematopoietic, hepatic, and renal systems. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Amidases   Thauera   Cloning   Characterization   BREVIBACTERIUM-EPIDERMIDIS ZJB-07021   ENANTIO-SELECTIVE AMIDASE   ACYL TRANSFER ACTIVITY   RECOMBINANT AMIDASE   NITRILE HYDRATASE   PURIFICATION   IDENTIFICATION   VERSATILE   DEGRADATION  

摘要： A novel amidase (TAM) was identified and cloned from the genome of Thauera sinica K11. The recombinant protein was purified to homogeneity by one-step affinity chromatography for up to 26.4-fold with a yield of 38.1%. Gel filtration chromatography and SDS-PAGE revealed that the enzyme was a tetramer with a subunit of approximately 37.5 kDa. The amidase exhibited the maximum acyl transfer activity at 45 degrees C and pH 7.0, and it was highly stable over a wide pH range of 6.0-11.0. Inhibition of enzyme activity was observed in the presence of metal ions, thiol reagents and organic solvents. TAM showed a broad substrate spectrum toward aliphatic, aromatic and heterocyclic amides. For linear aliphatic monoamides, the acyl transfer activity of TAM was decreased with the extension of the carbon chain length, and thus the highest activity of 228.2 U/mg was obtained when formamide was used as substrate. This distinct selectivity of amidase to linear aliphatic monoamides expanded the findings of signature amidases to substrate specificity.

关键词： DCL2   Dicer   Dicing assay   Neurospora crassa   Small RNA   DISTINCT ROLES   RNA   GENE   INTERFERENCE   PHOSPHATE   PROTEINS   SIRNA   MIRNA   DNA  

摘要： Dicing of double-stranded RNA (dsRNA) into small RNA is an essential process to trigger transcriptional and post-transcriptional gene silencing. Using cell-free extracts of the model filamentous fungus Neurospora crassa, we successfully detected the dicing activity of one of two N. crassa Dicers NcDCL2. The predominant 23-nucleotide (nt) cleavage product was always detected from 30-nt to 130-nt dsRNA substrates, and additional products of approximately 18 to 28 nt were occasionally produced. The enzymatic properties of NcDCL2 are different from those of insect and plant small interfering RNA (siRNA)-producing Dicers, Drosophila melanogaster Dicer-2 and Arabidopsis thaliana DCL3 and DCL4 (AtDCL3 and AtDCL4). Whereas AtDCL3 and AtDCL4 preferentially cleave short and long dsRNAs, respectively, NcDCL2 cleaved both short and long dsRNAs. These results suggest that N. crassa has a single siRNA-producing Dicer NcDCL2, which is a prototype of plant siRNA-producing Dicers with distinct functions in diverse RNA silencing pathways. The dicing assay reported here is convenient to detect and biochemically characterize the dicing activities of both plant and fungal Dicers, and is likely applicable to other organisms.