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关键词： Cypermethrin   Common carp   Oxidative stress   DNA damage   Apoptosis   Origanum vulgare  

摘要： The study was designed to evaluate the possible protective roles of dietary Origanum vulgare essential oil (OVEO) against cypermethrin (CP)-induced serum biochemical changes and oxidative stress of common carp (Cyprinus carpio). Moreover, histopathological alterations, apoptosis, cell proliferation, and DNA damage in the gills and hepatic tissues were also assessed. Briefly, fish were allotted into six groups with three triplicates whereas a group fed on basal diet and did not exposed to CP and served as control (CTR), two groups were fed on diets supplemented with two levels of OVEO (0.5 % and 1.0 %), a group exposed to sub-lethal concentration of CP (1/10 of 96 h-LC50 = 0.4134 mu g/L), and two other groups exposed to the same concentration of CP and fed on diets supplemented with both levels of OVEO (CP + 0.5 % OVEO, and CP + 1.0 % OVEO), respectively, for 30 days. CP induced significant elevation of serum alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), urea, and creatinine levels indicating hepato-renal toxicity (P < 0.05). Besides, there was a significant decrease in serum catalase (CAT) and superoxide dismutase (SOD) activities (P < 0.05). Moreover, CP induced significant histopathologic alterations in gills, anterior kidneys, and hepatic tissues with activation of apoptosis (Caspase-3) and proliferating cell nuclear antigen (PCNA). Comet assay demonstrated significant DNA damage in gills and liver tissues of the CP-exposed group. Interestingly, a significant attenuation of serum ALT, AST, ALP, urea, creatinine, CAT, and SOD levels (P < 0.05) was noticed in CP-exposed fish and concurrently fed diets supplemented with either 0.5 % or 1.0 % OVEO. Moreover, histopathologic alterations and apoptosis were significantly reduced along with a concomitant significant decrease in DNA damage (P < 0.05) which indicated the mitigation of DNA damage. Conclusively, the study showed that OVEO is an effective counteractive treatment against

关键词： Drugs   Crustaceans   Biomarkers   Population effects   Antifouling compounds   Sublethal effects  

摘要： Chemical toxicity in the environment may be the consequence of exposure of living organisms to multiple substances, with distinct putative effects. Among this mulytiplicity of chemicals that occur in the wild, pharmaceutical drugs and antifoulers are prone to exert toxic effects on non-target organisms. To characterize the toxicity elicited by a compound of this specific class, the present study used standard and biochemical-based tools to quantify the toxic response of the antifouler and antidandruff zinc pyrithione in Daphnia magna and Daphnia longispina. The analised parameters were immobility, reproduction, behavioral alteration (swimming patterns), anti-oxidant defense (catalase activity), metabolism (GSTs activities), and neurotoxicity (ChE activity) after exposure to sublethal concentrations of this drug. Exposure to zinc pyrithione has been shown to have neurotoxic and oxidative effects, with changes in swimming behavior. There were no changes in reproductive traits of exposed individuals, from both species. The obtained data demonstrate that ecologically relevant levels of zinc pyrithione can deleteriously alter critical parameters in two distinct freshwater microcrustacean species, although with distinct toxicity patterns and outcomes.

关键词： Pesticide   Narrow-clawed crayfish   Oxidative stress   Biochemical indicators   Immunological parameters  

摘要： Glyphosate is an herbicide that inhibits the growth of weed plants, while chlorpyrifos is an insecticide commonly applied to control the pests' population. This study aimed to investigate the combined effects of chlorpyrifos and glyphosate on biochemical, immunological parameters, and oxidative stress biomarkers in freshwater crayfish Pontastacus leptodactylus for 21 days. The experimental design of this study was factorial (3 x 3), including 0.0, 0.4, and 0.8 mg L-1 glyphosate and 0.0, 2.5, and 5 mu g L-1 chlorpyrifos. The exposure to chlorpyrifos, glyphosate alone and a mixture of them significantly decreased acetylcholinesterase, alkaline phosphatase, phenoloxidase activities, and total protein levels. The lactate dehydrogenase, glutamic-pyruvic-transaminase, and catalase activities, the contents of glucose, and malondialdehyde levels were increased in the crayfish. No significant changes were detected in glutamic-oxaloacetic-transaminase (SGOT) activity, triglyceride, and total antioxidant (TAO) levels in the crayfish treated with 0.4 mg L-1 glyphosate and the control group. Co-exposure of crayfish to chlorpyrifos and glyphosate increased SGOT activity and TAO levels. Although chlorpyrifos combined with glyphosate decreased the gamma-Glutamyltransferase (GGT) activity, the GGT activity was significantly increased in the P. leptodactylus exposed during 21 days to 5 mu g L-1 chlorpyrifos alone and 0.8 mg L-1 glyphosate alone. In comparison with the reference group, no significant changes were evidenced in the cholesterol levels in the P. leptodactylus treated with 2.5 mu g L-1 chlorpyrifos, but its levels were significantly increased in the other treatment groups. In conclusion, the mix of glyphosate and chlorpyrifos exhibited synergic effects on the different toxicological biomarkers in the narrow-clawed crayfish. Co-exposure to pesticides may result in disruption of homeostasis in the crayfish by altering the biochemical and immunological parameters.

关键词： Corals   Light pollution   ALAN   Photo-physiology   ROS   Photosynthesis  

摘要： Artificial Light at Night (ALAN), which is the alteration of natural light levels as the result of anthropogenic light sources, has been acknowledged as an important factor that alters the functioning of marine ecosystems. Using LEDs light to mimic ALAN, we studied the effect on the physiology (symbiont and chlorophyll contents, photosynthesis, respiration, pigment profile, skeletal growth, and oxidative stress responses) of two scleractinian coral species originating from the Red Sea. ALAN induced the photo inhibition of symbiont photosynthesis, as well as an overproduction of reactive oxygen species (ROS) and an increase in oxidative damage to lipids in both coral species. The extent of the deleterious effects of ALAN on the symbiotic association and coral physiology was aligned with the severity of the oxidative stress condition experienced by the corals. The coral species Sylophora pistillata, which experienced a more severe oxidative stress condition than the other species tested, Turbinaria reniformis, also showed a more pronounced bleaching (loss of symbionts and chlorophyll content), enhanced photoinhibition and decreased photosynthetic rates. Findings of the present study further our knowledge on the biochemical mechanisms underpinning the deleterious impacts of ALAN on scleractinian corals, ultimately shedding light on the emerging threat of ALAN on coral reef ecology. Further, considering that global warming and light pollution will increase in the next few decades, future studies should be taken to elucidate the potential synergetic effects of ALAN and global climate change stressors. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Anabas testudineus   Naphthalene   Glutamic pyruvic transaminase   Erythrocytes   PAHs  

摘要： Anabas testudineus (Bloch) was exposed to 0.71 mg/L and 1.42 mg/L (25 and 50% of LC(50 )value respectively) naphthalene, a polycyclic aromatic hydrocarbon (PAH), for 21 days. Blood biochemical parameters and erythrocytic morphological alterations were assessed to describe the naphthalene toxicity. Biochemical analysis showed a significant increase in glutamic pyruvic transaminase, GPT (576.7 +/- 11.79 and 608.9 +/- 12.08 U/L, respectively) and alkaline phosphatase, ALP (12.9 +/- 0.69 and 13.4 +/- 0.64 U/L, respectively) activities under two doses compared with control. Protein and albumin (ALB) content in blood decreased significantly, in comparison with control value in the tune of 22.67 +/- 1.04 and 23.97 +/- 1.24 g/dl, respectively and 10.7 +/- 0.79 and 11.1 +/- 0.67 g/dl, respectively. Erythrocytes showed varied symptomatic morphological changes under naphthalene exposure, which included severe denaturation, swelling in cells, appearance of sickle and tear drop cells, and cellular vacuolation. In particularly, the changes were more prominent under higher naphthalene exposure. Following the results, it has been able to establish that GPT, ALP, protein and ALB, and the morphological manifestations of erythrocytes would be good tools of biomarker in monitoring toxicological paradigm, especially to naphthalene exposure in aquatic bodies.

摘要： The COVID-19 outbreak has shut down universities and prompted the teaching faculty to move to online resources. In view of upcoming of new Medical Council of India (MCI) curriculum and outbreak of COVID-19 pandemic, keeping pace with medical education became a challenge. To keep on par with learning activities of undergraduate students during this period, the teaching faculty adopted the use of online resources. E-learning tools were utilized to engage first-year undergraduate students and satisfy majority of aspects of Competency-Based Undergraduate Medical Curriculum/Education (CBMC/E) in Biochemistry.

关键词： Theobroma cacao   Heavy metal   Photosynthesis   Oxidative stress   Gene expression   Micromorphology  

摘要： Cadmium (Cd) is a trace metal without essential biological function due to its high toxicity to plants, animals and humans, even at low concentrations. On the other hand, Zn is an essential nutrient and plays important metabolic functions in plants. The study of the interaction between essential and a nonessential element may be important for understanding, analyzing and improving the defense strategies adapted by plants. The main objective of this work was to evaluate the mitigation of Cd toxicity by Zn in young plants of the CCN 51 cocoa genotype, grown in soil with different concentrations of Zn, Cd and Zn + Cd, through physiological, biochemical, molecular and micro-morphological responses. It was verified that high concentrations of Zn, Cd and Zn + Cd in the soil promoted alterations in the enzymatic and non-enzymatic antioxidative metabolism and expression of genes. This was demonstrated by increase in the activity of antioxidative enzymes, proline content and reduction in lipid peroxidation. Leaf gas exchange was affected at the highest soil Cd concentrations (0.4, 0.6 and 0.8 mmol Cd kg(-1) soil) combined with different soil Zn concentrations (0.4, 0.8, 1.2 and 1.6 mmol kg(-1) soil), resulting in a decrease in CO2 fixation. The higher concentration of soil Cd (0.8 mmol kg(-1) soil), together with the intermediate concentrations of soil Zn + Cd (0.8 + 0.4 and 0.4 + 0.6 mmol kg-1 soil), promoted reduction of the thickness of the leaf mesophyll and, consequently, led to decrease of the leaf gas exchange. It was observed a hormesis effect due to high photosynthetic activity in low Cd concentration. The increase in Cd concentration in the soil altered the uptake of Cd and Zn by the roots of the CCN 51 cocoa genotype. The increase of Zn concentration in the soil promoted the decrease of the Cd uptake by the root system of the plants and thereby reduced the transport of Cd to the leaves. Part of Cd uptake by the plant's root system was immobilized in roots tissues,

关键词： Noctiluca scintillans   Mesodinium   Red tides   Physical-biochemical coupling processes  

摘要： Red tide has always been an environmental issue with global concern. A Noctiluca scintillans red tide and a Mesodinium red tide occurred successively in Yantai nearshore, China, where is usually oligotrophic, in October 2019. Currents, phytoplankton community composition and nutrients were analyzed to access the driving factors of the red tides. The maximum N. scintillans and Mesodiniium abundance reached 124.92 +/- 236.84 x 10(3) cells/ L and 1157.52 +/- 1294.16 x 10(3) cells/L respectively. The fast growth of N. scintillans was due to increasing abundance of phytoplankton. The currents were crucial to the assembly and dispersal of red tides. The red tides significantly redistributed the nutrients in the red tide patches and regulated the dominant species in phyto-plankton community. Our study illuminates the influence of physical-biochemical coupling processes on red tides, and suggests that ocean dynamics such as currents and tidal factors deserve more attention when considering the ecosystem health problems of coastal zones.

关键词： Active learning   Teaching practices   Assessment practices   Pedagogical practices   Biochemistry and molecular biology  

摘要： As higher education transitions from an exclusivist to a more accessible endeavour, class sizes are continuously increasing, prompting academics to explore different strategies to facilitate quality learning. In this paper, we explore the current practices of Australian biochemistry and molecular biology academics to understand how academics cope with the mass education context, and whether there are specific blocks to the introduction of active learning into these classrooms. We utilised inductive thematic analysis to identify the themes underpinning the pedagogical practices of a selection of academics in biochemistry and molecular biology. These data indicated that these academics: (1) consider themselves to be, and are, traditional teachers;(2) believe that their students will learn better the way that they were taught at university;(3) are trying to shift their teaching from traditional to non-traditional;and (4) practice reflective teaching. These findings suggest that these pedagogical practices are primarily influenced by the academics' own presumptions and educational beliefs on how the specific discipline should be taught. Engagement in professional development appears to be influencing some academics to shift their teaching towards a more active and student-centred focus, but still, a lack of formal education qualification is holding many academics back from fully engaging with current pedagogical best practice. The findings in this study are broadly applicable to many higher education disciplines.