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关键词： biochemistry and molecular biology   conference report   discipline‐   based education research   education   publishing  

摘要： Ensuring currency with trends, knowledge, and understanding of teaching and learning is essential for all educators. Researching learning and teaching is an enormous field which can range from examining the practical impact of new classes to research into the processes of learning. The "Publishing in Education" conference session discussed some of the approaches and outcomes of researching and publishing in education.

关键词： Conyza dioscoridis   protease inhibitor   characterization antimicrobial effect   protein therapeutics  

摘要： The main objective of the current study was the extraction, purification, and biochemical characterization of a protein protease inhibitor from Conyza dioscoridis. Antimicrobial potential and cytotoxic effects were also examined. The protease inhibitor was extracted in 0.1 M phosphate buffer (pH 6-7). Then, the protease inhibitor, named PDInhibitor, was purified using ammonium sulfate precipitation followed by filtration through a Sephadex G-50 column and had an apparent molecular weight of 25 kDa. The N-terminal sequence of PDInhibitor showed a high level of identity with those of the Kunitz family. PDInhibitor was found to be active at pH values ranging from 5.0 to 11.0, with maximal activity at pH 9.0. It was also fully active at 50 degrees C and maintained 90% of its stability at over 55 degrees C. The thermostability of the PDInhibitor was clearly enhanced by CaCl2 and sorbitol, whereas the presence of Ca2+ and Zn2+ ions, Sodium taurodeoxycholate (NaTDC), Sodium dodecyl sulfate (SDS), Dithiothreitol (DTT), and beta-ME dramatically improved the inhibitory activity. A remarkable affinity of the protease inhibitor with available important therapeutic proteases (elastase and trypsin) was observed. PDInhibitor also acted as a potent inhibitor of commercial proteases from Aspergillus oryzae and of Proteinase K. The inhibitor displayed potent antimicrobial activity against gram+ and gram- bacteria and against fungal strains. Interestingly, PDInhibitor affected several human cancer cell lines, namely HCT-116, MDA-MB-231, and Lovo. Thus, it can be considered a potentially powerful therapeutic agent.

关键词： Acid coagulation   Afuega'l Pitu cheese   Biochemistry   Proteolysis   Ripening   Thermal profiles   Viscoelastic properties  

摘要： Thermoviscoelastic and biochemical properties of Afuega'l Pitu cheese blancu (B) and roxu (R), a Spanish acid-curd cheese made from cow's milk, were determined at 3, 15, 30 and 60 days of ripening. The contents of fat (>45 g/100 g total solids, TS) and NaCl (<3 g/100 g TS) were similar between varieties and did not change with ripening. Total solids, pH, nitrogen fractions and fat acidity increased with ripening time in B and R samples. Lactose content was higher in B than in R cheeses at 3 d, was degraded gradually throughout ripening but did not disappear totally in both cheeses at 60 d. Viscoelastic parameters were determined in the linear viscoelastic region (LVER) by stress sweeps (6.3 rad/s, 20 degrees C): the stress amplitude (sigma(max)) and complex modulus (G*) increased, while strain amplitude (gamma(max)) decreased up to 60 d. Mechanical spectra were also determined, in the LVER, at 20 degrees C, 50 degrees C and 75 degrees C, showing that all samples behaved as "true gels" (elastic modulus, G' > viscous modulus, G''), irrespective of temperature. The best gel properties (low values of loss factor, tan delta = G''/G', and minor frequency dependence, i.e., low n', n'' exponents), were observed at 20 degrees C for B30 and R30. The viscoelastic parameters (G(0)' and G(0)'') increased with ripening time, irrespective of the temperature, and for a fixed ripening time they were lower at higher temperature. At 75 degrees C, all samples exhibited notable frequency dependence (n'' >> n'), resulting in shear-induced gelation at low frequencies (high oscillation times) which was consistent with data in thermal profiles from 70 degrees C to 90 degrees C.

关键词： Beta-thalassemia   Saudi   Inherited   Hemoglobin   Anemia  

摘要： Introduction: Beta-thalassemias are a group of inherited blood disorders caused by reduced or absent synthesis of beta chain of hemoglobin resulting in variable phenotypes ranging from clinically asymptomatic individuals to severe anemia symptoms. The objective of this study is to screen for the whole beta gene globulin and the LCR region and its clinical relevance in beta-Thalassemia patients. Methods: In this study, we collected 140 blood patients' samples with beta-thalassemia from different areas of Saudi Arabia. DNA was then extracted then the molecular scanning for the whole beta-globin gene and the Locus control region (beta-LCR) for patients' samples, was run using PCR. Results: Sixty one mutations found in this study, including 22 new mutations not recorded in the database before. These deletions including: (*C-1960-1961 ca/- del in hbb5) and (*c-519C A het in hbb9). Interestingly, the highest percentage in gene deletion occurred in exon 03A by similar to 33% of the samples, while the highest percentage in gene addition of the gene occurred in exon 03B by similar to 25%. Conclusion: This study was unique to show several new mutations that would help in diagnosis and treatment. These results should be taken further to set up better management strategies to improve outcomes. (C) 2020 Published by Elsevier B.V. on behalf of King Saud University.

关键词： Biomonitoring   PERMANOVA   RDA   Pesticides   Metals  

摘要： Reservoirs are lentic man-made waterbodies resulting from river damming processes. Pollutants coming from adjacent areas can accumulate in the water and sediment of these modified freshwater environments. Fish are often found in reservoirs occupying several trophic niches. Biochemical biomarkers are early warning signals of environmental disturbance to an organism. It is essential to understand how pollutants, abiotic variables and biochemical biomarker responses behave throughout the seasons to implement biomonitoring programs. Loricariichthys anus and Geophagus brasiliensis were collected, and abiotic variables were seasonally measured for one year, at six sampling sites in Passo Real reservoir, in a subtropical region of Southern Brazil. Biochemical biomarkers were analyzed in four tissues of both fish species, as well as metal and pesticide concentrations in the reservoir's water and sediment. Redundancy analysis (RDA) was carried out to find the temporal relationship between biomarkers and environmental variables. RDA has clearly shown the separation of seasons for both species. Azoxystrobin, simazine and propoxur were the pesticides mostly contributing to the variation, whereas metals had lesser contribution to it. Seasonality appears to be the main factor explaining biomarkers' variability. PERMANOVA has confirmed the effect of temperature and dissolved oxygen on biomarkers of both fish species. Thus, it is hard to differentiate if the fluctuation in biomarkers' responses only reflects the normal state of organisms or it is a biological consequence from negative effects of fish exposure to several types of pollution (sewage, pesticides, and fertilizers) entering this aquatic system. In this study, to circumvent the seasonality issue on biomonitoring, the analysis of biomarkers on these fish should not be carried out in organs directly affected by temperature (such as liver and gills), or during reproduction periods (mainly in Spring). (C) 2020 Elsevier Ltd. A

关键词： Subtilisin   Keratin   Soil biostimulation   DNA metabarcoding   Biodiversity  

摘要： Proteinaceous material constitute the main source of nitrogen in soil organic matter. Use of this nitrogen is limited by the breakdown of proteins into peptides and free amino acids. Proteases, therefore, are important in the use of protein N. The aim of this study is to assess the effect of subtilisin, which is a soil extracellular endopeptidase from Bacillus sp., both on soil microbial biostimulation and biodiversity. In addition to the protease, keratins, an insoluble-protein and low-bioavailable substrate, was added to enhance the effect of protease in soil. Protease, both on its own and in combination with keratins, has a biostimulant effect on soil microbial activity that was reflected in the protease, dehydrogenase and phosphatase activities. DNA metabarcoding analysis further revealed specific changes in soil biodiversity, mainly defined by the enrichment of plant-growth promoting microorganisms, specifically those producing hydrolase enzymes such as phosphatase and ammonifiers. Surprisingly, the addition of keratins specifically showed a rapid stimulation of soil proteolytic bacteria. Thus, the present work supports the use of subtilisin as biofertiliser and values the recycling of keratinous industrial waste in the field of biofertilisation.

关键词： Aurantiochytrium sp. (Schizochytrium sp.)   Renewable resource   Cost   Stimulator   Genetic engineering   Docosahexaenoic acid (DHA)  

摘要： The marine oleaginous protist Aurantiochytrium sp. (Schizochytrium sp.) is a well-known docosahexaenoic acid (DHA) producer and its different DHA products are the ideal substitute for the traditional fish oil resource. However, the cost of the DHA products derived from Aurantiochytrium sp. (Schizochytrium sp.) is still high, limiting their wide applications. In order to reduce the cost or improve the productivity of DHA from the microbial resource, many researches are focusing on exploring the renewable and low-cost materials as feedbacks, and/or the stimulators for biomass and DHA production. In addition, the genetic engineering is also being used in the Aurantiochytrium sp. (Schizochytrium sp.) system for further improvement. These break the bottleneck of the DHA production by Aurantiochytrium sp. (Schizochytrium sp.) in some degree. In this review, the strategies used currently to reduce cost and improve DHA productivity, mainly from the utilizations of low-cost materials and effective stimulators to the genetic engineering perspectives, are summarized, and the availabilities from the cost perspective are also evaluated. This review provides an overview about the strategies to revolve the production cost and yield of the DHA by Aurantiochytrium sp. (Schizochytrium sp.), a theoretical basis for genetic modification of Aurantiochytrium sp. (Schizochytrium sp.), and a practical basis for the development of DHA industry.

关键词： continuing   education   biochemistry and molecular biology   conference report   education   industry  

摘要： Science requires that we are always current with research, techniques, and tools but what are the best approaches for continuing education? The presenters in this session described a range of approaches used in universities, government bodies, and industry.

关键词： Allium fistulosum   usnic acid   phytotoxicity   genotoxicity   oxidative stress  

摘要： The effect of (+) and (-)-usnic acid (UA) on the physiological, biochemical, and cytological characteristics ofAllium fistulosumL. seedlings was studied. It was shown that germination of seeds in the medium supplemented with both enantiomers of UA at concentrations of 62.5-1000 mu M led to a decrease in laboratory germination, an inhibition of growth processes, a slowing of the mitotic activity of root meristems, and tissue depigmentation. A dose-dependent increase in the frequency of chromosomal aberrations and the degree of damage to nuclear DNA in cells was shown, which indicates the potentially genotoxic and mutagenic effect of the studied UA enantiomers. However, (-)-UA induced a greater number of atypical DNA comets than the (+)-enantiomer, which may indicate its stronger effect on DNA fragmentation in cells. An increase in the activity of antioxidant enzymes and a decrease in the content of flavonoids were observed under the action of both UA enantiomers against the background of the accumulation of lipid peroxidation products in seedlings' cells, which indicates the development of oxidative stress. At the same time, no significant differences between the activity of (+) and (-)-UAs at the level of physiological and biochemical parameters of seedlings were revealed.

关键词： Exercise   Aging   Sarcopenia   Lean mass   Fat mass   Physical performance   Glucose homeostasis  

摘要： Background: The aim of the following study was to identify the effects of a 12-week high-intensity interval training (HIIT) program on the modification of parameters of body composition, functional capacity as well as lipid and glucose homeostasis markers in healthy young people versus older adults. Design: Experimental trial. Methods: Healthy young (YNG, 21 +/- 1 years, BMI 26.01 +/- 2.64 kg.m(-2), n = 10) and older (OLD, 66 +/- 5 years, BMI 27.43 +/- 3.11 kg.m(-2), n = 10) males were subjected to 12 weeks of HIIT. Prior to and immediately after the HIIT program, dual-energy X-ray absorptiometry, dominant leg strength one-repetition maximum (1-RM), maximal oxygen uptake (VO2max) and physical performance tests were performed. Blood samples were also taken. Results: Flexibility (P = 0.000), static balance (P = 0.004), timed up and go test (TUG) (P = 0.015), short physical performance battery (SPPB) (P = 0.005), dominant leg strength 1-RM (P = 0.012), and VO2max (P = 0.000) were better in YNG versus OLD. HIIT improved the % whole-body fat mass (P = 0.031), leg lean mass (P = 0.047), dominant leg strength 1-RM (P = 0.025), VO2max (P = 0.000), fasting cholesterol (P = 0.017) and fasting glucose (P = 0.006). TUG was improved by the training only in the OLD group (P = 0.016), but insulin (P = 0.002) and the homeostasis model assessment - insulin sensitivity (HOMA-IS) (P = 0.000) decreased only in the YNG group. HOMA-IS was correlated positive with BMI (R = 0.474, P = 0.035) and with whole-body fat mass (R = 0.517, P = 0.019). Conclusions: HIIT for 12 weeks improves parameters of body composition, functional capacity and fasting serum lipid and glucose homeostasis markers in healthy young and older participants. Young people are shown as benefiting more.