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关键词： MS-222   Development   Oxidative stress   Apoptosis   Cell proliferation   Zebrafish  

摘要： MS-222, the most widely used anaesthetic in fish, has been shown to induce embryotoxic effects in zebrafish. However, the underlying molecular effects are still elusive. This study aimed to investigate the effects of MS-222 exposure during early developmental stages by evaluating biochemical and molecular changes. Embryos were exposed to 50, 100 or 150 mg L-1 MS-222 for 20 min at one of three developmental stages (256-cell, 50% epiboly, or 1-4 somite stage) and oxidative-stress, cell proliferation and apoptosis-related parameters were determined at two time-points (8 and 26 hpf). Following exposure during the 256-cell stage, the biochemical redox balance was not affected. The genes associated with glutathione homeostasis (gstpi and gclc) were affected at 8 hpf, while genes associated with apoptosis (casp3a and casp6) and cellular proliferation (pcna) were found affected at 26 hpf. An inverted U-shaped response was observed at 8 hpf for catalase activity. After exposure at the 50% epiboly stage, the gclc gene associated with oxidative stress was found upregulated at 8 hpf, while gstpi was downregulated and casp6 was upregulated later on, coinciding with a decrease in glutathione peroxidase (GPx) activity and a non-monotonic elevation of protein carbonyls and casp3a. Additionally, MS-222 treated embryos showed a decrease in DCF-staining at 26 hpf. When exposure was performed at the 1-4 somite stage, a similar DCF-staining pattern was observed. The activity of GPx was also affected whereas RT-qPCR showed that caspase transcripts were dose-dependently increased (casp3a, casp6 and casp9). The pcna mRNA levels were also found to be upregulated while gcic was changed by MS-222. These results highlight the impact of MS-222 on zebrafish embryo development and its interference with the antioxidant, cell proliferation and cellular death systems by mechanisms still to be explained;however, the outcomes point to the Erk/Nrf2 signalling pathway as a target candidate.

关键词： Omentin   Obesity   Adipose tissue   Insulin   Anthropometry  

摘要： Objective: Omentin is a secretory protein produced in visceral adipose tissue. The potential protective action of omentin in metabolic disorders is not yet fully understood. The aim of this study was to determine the association of omentin with anthropometric, physiologic, and biochemical parameters in obese individuals. Methods: Sixty obese individuals and 40 normal weight controls were enrolled in the study. Anthropometric measurements were taken, systolic (SBP) and diastolic blood pressures (DBP) were recorded. Serum fasting glucose, insulin, homeostatic model assessment of insulin resistance (HOMA-IR), lipid profile, and serum omentin concentrations were determined. Results: The concentration of omentin in obese individuals was significantly lower than in controls (145.5 +/- 33.3 versus 383.6 +/- 92.9;P < 0.001). Omentin correlated negatively with waist circumference (P < 0.01), hip circumference (P < 0.05), percent of adipose tissue (P < 0.001), fasting insulin (P < 0.001), HOMA-IR (P < 0.001), and SBP (P < 0.001) in the patients who were obese. A positive relationship was documented with high-density lipoprotein in both the obese patients (P < 0.01) and the overall population (P < 0.001). Multiple negative omentin correlations with body weight, body mass index, waist and hip circumference and its ratio, percent of adipose tissue, SBP, triacylglycerols, glucose, fasting insulin, and HOMA-IR were demonstrated in the entire population. In the multivariate linear regression model, insulin concentration (beta = -0.49;P < 0.001), percent of adipose tissue (beta = -0.31;P < 0.001), and waist circumference (beta = -0.21;P < 0.01) were independent predictors of omentin concentration in individuals who were obese. Conclusions: A concentration of omentin is associated with cardiometabolic risk-related factors in obesity. Fasting insulin, adipose tissue percentage, and waist circumference can be considered candidates for markers of omentin concentration in obese individua

摘要： Objective This study aimed to investigate the relationship between fluid and sodium excretion and blood pressure, echocardiographic parameters, and arterial stiffness in peritoneal dialysis (PD) patients and to evaluate the effect of sodium excretion on patients' survival. Method This study was conducted as a single-centered, prospective study in the Department of Nephrology in Erciyes University. The patients included in the study were followed up for 3 years. Seventy PD patients were included in the study. We recorded demographic characteristics, biochemical parameters, urine and peritoneal ultrafiltration volumes, peritoneal equalization tests, ambulatory blood pressure measurements, and echocardiographic measurements. We measured the amount of total sodium excretion of the patients and arterial stiffness using pulse wave velocity (PWV). Patients were divided into two groups based on the amount of total sodium excretion: low group and high group. We compared these groups in terms of cardiac and biochemical parameters. Results When demographic data and biochemical values were compared, there was no significant difference between the two groups. NT-proBNP level, systolic blood pressure, and mean arterial pressure were significantly higher in the low group (p: 0.02,p: 0.031,p: 0.05, respectively). Net ultrafiltration was significantly higher in the high group (p: 0.03), was also found to be high in patients with high sodium excretion (p: 0.001). Negative correlations were found between sodium excretion and net ultrafiltration, NT-Pro BNP, and PWV. At the end of the 3-year follow-up, the survival rate was shorter and the mortality rate was higher in the low group (p: 0.042). Discussion and conclusion Fluid status in PD patients can affect arterial stiffness both directly and through hypertension. Correction of hypervolemia has the potential to not only prevent hypertension and left ventricular hypertrophy, but also to improve arterial stiffness, a well-known cardiova

关键词： 2019   biochemistry and molecular biology   conference report   postgraduate programs  

摘要： The conference session on Postgraduate Education in Biochemistry and Molecular Biology consisted of wide-ranging presentations and discussions. Approaches, issues, and solutions for postgraduate education and training in countries ranging from the Philippines to Mongolia and the United States were covered.

关键词： biochemistry and molecular biology   conference report   education   laboratory classes   practicals  

摘要： Laboratory classes are a central element of all biochemistry and molecular biology programs. These play a role in developing students' hands-on and technical skills and also offer much more. The design of laboratory classes depends on many factors including the programs the students are enrolled in, the level they are at, employment destinations, and learning outcomes. This conference session considered the design and outcomes of laboratory experiences for undergraduate students.

关键词： biochemistry and molecular biology   conference report   education   K-12  

摘要： Biochemistry and molecular biology education starts before our students get to university. From a very early age, they start learning informally about science beginning with the basics of science and as they progress through their school years they should be exposed to more advanced topics such as biochemistry and molecular biology. This session at the conference focused on three very different examples of engaging school students with biochemistry and molecular biology.

关键词： Benzo[a]pyrene   Bile metabolites   EROD   GST   Oxidative stress  

摘要： The biotransformation ability of the organism is the result of organ-specific responses. This paper presents a molecular and biochemical approach to elucidate the biotransformation mechanisms in different organs of Prochilodus lineatus induced at 6, 24, and 96 h after a benzo [al pyrene (B [al P) injection. The induction in cypla transcription showed an organ-specific intensity at every tested time time. The EROD (ethoxyresorufin-O-deethylase) activity increased rapidly (6 h) in the liver and the kidney;the gills and the brain showed an increase at 24 h;and the gills demonstrated the highest activity among all the organs tested. There was no increase in glutathione S-transferase (GST) activity or lipoperoxidation. The decreased hepatic glutathione content (GSH) may be due to its role as an antioxidant. B[a]P was detected in the bile, confirming the xenobiotic efflux from the metabolizing organs. The gills, liver, brain, and kidney of P. lineatus presented an integrated mechanism to deal with the xenobiotic biotransformation.

关键词： biochemistry of nutrition   comparative biochemistry   teaching and learning techniques methods and approaches  

摘要： The interdisciplinary subject of agricultural biochemistry can provide an abundance of didactic opportunities for educators teaching biochemistry and molecular biology in secondary-level science courses. This is especially true in present times when virtual-learning strategies supersede in-person instruction and contemporary approaches are needed to engage students with relevant applications of science. In this communication, we discuss how pairing daily lessons in agricultural biochemistry with periodic e-notebook usage further refines this strategy by promoting content-retrieval and providing educators with formative feedback on student progress in a simple and inexpensive manner.

关键词： Channel catfish   Waterless preservation   Anesthetization   Chilling rate   Biological  

摘要： Cold-anesthetization waterless live fish preservation is considered a promising alternative strategy. This work investigates the effects of temperature chilling rates of 2, 4, and 6 degrees C/h on serum biological parameters and muscular chemical composition of channel catfish Ictalurus punctatus and the influence of waterless preservation time (6, 9, 12, 15, and 18 h) on survival after subjection to three chilling rates. Fish subjected to increasing chilling rates showed lower survival and shorter preservation time. The research results revealed that a temperature gradient drop of 2 degrees C/h was conducive to maintaining the activity of creatinine (CREA), lactic dehydrogenase (LDH), and pyruvate kinase (PK). The serum aspartic transaminase (AST) and alanine transaminase (ALT) activity dramatically increased after anesthetization. Blood urea nitrogen (BUN) and CREA, whose activity is sensitive to hydropenic conditions, increased significantly after waterless preservation and showed a slight reversal after recovery. Anesthetization caused a significant decrease in protein and fat in muscle, while no obvious trend was observed among different chilling groups. Muscle glycogen (MG) and water-holding capacity (WHC) decreased after anesthetization, then increased after preservation for 12 h, and decreased again after recovery for 24 h. The muscle pH showed the opposite trend. It can be concluded that the whole process resulted in marked changes in the muscle chemical composition. The development of a new green method for anesthetization of live channel catfish for long-term waterless preservation in the present work helps to determine the physiological changes that occur during preservation, providing an effective reference for investigation in other freshwater fish.

关键词： 生物学  

ISBN: (纸本)9787030649720

摘要： 本教材包括五篇共二十一章内容。第一篇为生物大分子的结构与功能，包括蛋白质的结构与功能、核酸的结构与功能以及酶与维生素，共三章。第二篇为物质代谢及其调节，包括生物氧化、糖代谢、脂质代谢、氨基酸代谢、核苷酸代谢及物质代谢的联系与调节，共六章。第三篇为遗传信息传递及其调控，包括DNA的生物合成、RNA的生物合成、蛋白质的生物合成和基因表达及其调控，共四章。除上述三篇基本内容外，本教材还根据医学学习要求，设置了两篇专题内容。第四篇为生物化学专题，主要涉及器官和组织细胞的生物化学，包括肝的生物化学、血液的生物化学和细胞信号转导，共三章。第五篇为分子生物学专题，主要涉及分子医学相关内容，包括癌基因与抑癌基因、常用分子生物学技术、DNA重组与基因工程、基因诊断和基因治疗、组学，共五章。除绪论对全书内容做系统介绍外，各篇的首页均有引言，各章的开头也有内容提要，旨在帮助学生理解和掌握全篇的主要内容和各章的要点，每章后附参考文献和微课视频。