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关键词： Sodium benzoate   Micronucleus   Comet assay   Chromosomal abnormalities   Molecular docking   Lipid peroxidation   Antioxidant enzymes  

摘要： In this study, the protective role of royal jelly (RJ) against the potential toxic effects of sodium benzoate was investigated in Allium cepa L. test material with physiological, genetic, and biochemical parameters. Physiological changes were evaluated by determining weight gain, rooting percentage, root length, and relative injury rate. The genetic evaluations were carried out with chromosomal abnormalities (CAs), micronucleus (MN), tail DNA formation, and mitotic index (MI) ratio parameters. The biochemical evaluations were carried out by determining lipid peroxidation and antioxidant enzyme activities by determining levels of malondialdehyde (MDA), glutathione reductase (GR), superoxide dismutase (SOD), and catalase (CAT). Further, the interaction of sodium benzoate with antioxidant enzymes was evaluated with molecular docking analysis. The antimutagenic effect of RJ was evaluated as the inhibition of chromosomal abnormalities (CAs) and tail DNA formations. A total of six groups were formed in the study. A. cepa L. bulbs in the control group were treated with tap water;the bulbs in the administration groups were treated with sodium benzoate (100 mg/L), RJ (25 mg/L and 50 mg/L doses), and sodium benzoate-RJ combinations with these doses for 72 h. As a result, it was determined that sodium benzoate application caused inhibition of physiological parameters and MI;induced MN, CAs, and DNA damage;and also caused oxidative stress. Depending on the concentration of RJ application, it reduced sodium benzoate toxicity by showing therapeutic effects in all these parameters. Also, the interaction of sodium benzoate with antioxidant enzyme residues was determined by molecular docking analysis. As a result, it has been understood that abandoning the use of sodium benzoate will be beneficial for the environment and human health and concluded that the use of RJ in the daily diet will be effective in reducing the impact of exposed toxic ingredients.

关键词： Crop residue   Residue quality   C-13 NMR   Aggregate stability   Soil structure  

摘要： Soil aggregation is deeply impacted by the quality of organic materials. However, the organic material features that control soil aggregation dynamics are still largely unknown. In this study, a total of 11 organic residues including vetch (alfalfa, hairy, and Chinese milk), straw (rice, maize, wheat, miscanthus, soybean, and sorghum) and manures (cattle and pig) were characterized by stoichiometric, biochemical and C functional features. The soil respiration, mean weight diameter (MWD) and glomalin-related soil protein (GRSP) levels were measured during 56 d of incubation. The results showed that stoichiometric features had no impact on soil respiration and aggregate stability except the N content. Residue decomposition was positively affected by soluble sugars but negatively affected by lignin and cellulose in the first 14 d (P < 0.05). Soluble sugars positively influenced the MWD up to 28 d, and cellulose continued this effect at 56 d (P < 0.05). Soil respiration and MWD were positively associated with alkyl and carbonyl C but negatively related to the alkyl and di-O-alkyl C fractions in the first two weeks, while adverse effects on the MWD were found at 56 d of incubation (P < 0.05). Organic residue input increased the GRSP level in the order of manure > straw > vetch. The GRSP content had a negative effect on the MWD up to 28 d (P < 0.05) but was not related at 56 d of incubation. Overall, high levels of soluble sugars of residues resulted in transient aggregate stability, but persistent aggregate stability was mainly contributed by the cellulose, O-alkyl C and di-O-alkyl C features.

关键词： Ruminants' gut   Xylanase   Mannanase   Partial purification   Characterization   Kinetic parameters  

摘要： Bacteria from the rumen of goats and cows were screened for endo-xylanase and beta-mannanase production. Among bacterial isolates initially screened, isolates represented by C12 and C14 identified by 16S rRNA Gene Sequence as Providencia vermicola and Psychrobacter pulmonis had the highest xylanase and mannanase activity, respectively. The crude enzymes were partially purified by ammonium sulphate and biochemical properties were determined. The partially purified xylanase and mannanase were optimal at pH 9.0 and 4.0, and at temperatures 40 and 60 degrees C respectively. The maximal pH stability of xylanase and mannanase residual activities were achieved at pH 6.0 and 5.0 respectively, while both enzymes were thermally stable with residual activity of 86% recorded for xylanase at 60 degrees C after 30 min and 67-83% for mannanase at 40-60 degrees C after 1 h. The activities of the enzymes were exceptionally and notably stimulated by Pb2+, SDS, and EDTA, while the K-m for xylanase and mannanase were 0.73 mg/ml and 4.60 mg/ml, respectively. Novel biochemical properties such as thermal stability, surfactant and metal tolerant, ability to tolerate alkali and acidic conditions including high affinity for substrates of xylanase and mannanase from bacteria in the rumen of ruminants made them candidates for many industrial processes especially pulp-bleaching.

关键词： RNA therapeutics   SARS-CoV-2   Mutation   COVID-19   Drug safety and drug efficacy  

摘要： Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic. Three viral proteins, the spike protein (S) for attachment of virus to host cells, 3-chymotrypsin-like cysteine protease (Mpro) for digestion of viral polyproteins to functional proteins, and RNA-dependent-RNA-polymerase (RdRp) for RNA synthesis are the most critical proteins for virus infection and replication, rendering them the most important drug targets for both antibody and chemical drugs. Due to its low-fidelity polymerase, the virus is subject to frequent mutations. To date, the sequence data from tens of thousands of virus isolates have revealed hundreds of mutations. Although most mutations have a minimum consequence, a small number of non-synonymous mutations may alter the virulence and antigenicity of the mutants. To evaluate the effects of viral mutations on drug safety and efficacy, we reviewed the biochemical features of the three main proteins and their potentials as drug targets, and analyzed the mutation profiles and their impacts on RNA therapeutics. We believe that monitoring and predicting mutation-introduced protein conformational changes in the three key viral proteins and evaluating their binding affinities and enzymatic activities with the U.S. Food and Drug Administration (FDA) regulated drugs by using computational modeling and machine learning processes can provide valuable information for the consideration of drug efficacy and drug safety for drug developers and drug reviewers. Finally, we propose an interactive database for drug developers and reviewers to use in evaluating the safety and efficacy of U.S. FDA regulated drugs with regard to viral mutations.

关键词： Fish   Migration   Feeding   Reproduction   Biochemistry   Bioenergetic reserves   Lipid   Fatty acid biomarkers   Physiological effect   Humboldt current system  

摘要： In the Southeast Pacific Ocean, Xiphias gladius migrates through the Chilean coastal zone for feeding. Here, it forages for different prey items from autumn to spring, acquiring a great variety of energy and nutritional reserves. We evaluated seasonal variations in the biochemical reserves (i.e., contents of lipids, proteins, and glucose), total energy content and fatty acid profile of specimens captured during the austral autumn, winter, and spring. Our results show that higher amounts of lipids were found in the winter and spring, while protein and glucose were higher in the autumn. Thus, the energy content showed significant differences, with higher levels in winter and spring. Furthermore, the fatty acid profile was more diverse in the spring than the autumn and winter and was characterized by higher amounts of polyunsaturated fatty acids. These findings suggest that temporal changes in the biochemical reserves, total energy content and fatty acid profile support the idea of a "trophic migration" (i.e., the feeding period) established by the dynamics of fishery fleets. The high amounts of lipids and diverse fatty acid profile found in the spring could indicate the end of the trophic migration during this season. Thus, X. gladius may reach an optimum nutritional condition in the spring and make energetic adjustments to carry out its reproductive migration during the austral summer. Therefore, this species seems to meet the high energy demands of the reproductive season by foraging for a wide range of prey items from autumn to spring and storing an increased amount of lipids at the end of the feeding period. Overall, our data provides crucial baseline knowledge for future research on the ecophysiology of X. gladius, as well as for the management and conservation of this fishery resource under an ecosystem approach.

关键词： Postharvest treatment   Fruits   Chilling injury   Biochemical mechanisms  

摘要： Background: Owing to the postharvest mass loss in most tropical and subtropical fruits and vegetables caused by chilling injury (CI), it is necessary to look for effective technologies to alleviate this issue. Studies thus far have found that some postharvest technologies could effectively alleviate CI in post-harvest fruits and vegetables. Scope and approach: This review summarizes the temperature and symptoms of CI in common postharvest fruits and vegetables. The postharvest technologies to control CI, which comprised physical (low-temperature conditioning, heat treatment, near-freezing temperature, controlled atmosphere, edible coating and ultraviolet irradiation) and chemical (ethylene and 1-methylcyclopropene, oxalic acid, calcium ions, nitric oxide, melatonin, salicylates and jasmonates, polyamines, and some other chemical substances) treatments, are also detailed. The potential biochemical mechanisms of different postharvest technologies are also proposed and attributed to the following strategies: maintaining membrane structure and sufficient energy supply, enhancing the antioxidant system, promoting the arginine pathway, regulating sugar metabolism, and activating the C-repeat/dehydration response element binding factor (CBF) genes. Key findings and conclusions: This review found that a variety of postharvest treatments have been developed to control CI in postharvest fruits and vegetables. The key findings were that the effects of some postharvest treatments & mdash;such as ethylene and 1-methylcyclopropene & mdash;on fruit and vegetable CI are contradictory. Some key factors, such as the time and temperature of heat treatment and the dose of ultraviolet radiation, need to be regarded when applying postharvest technologies. Some small-molecule signal substances that from natural plant and the combination of different treatments are potential future research directions for controlling CI in postharvest fruits and vegetables.

关键词： COVID-19   Diagnosis   Severity   Blood test   Urine test   Machine learning model  

摘要： Objective: This study aimed to implement and evaluate machine learning based-models to predict COVID-19' diagnosis and disease severity. Methods: COVID-19 test samples (positive or negative results) from patients who attended a single hospital were evaluated. Patients diagnosed with COVID-19 were categorised according to the severity of the disease. Data were submitted to exploratory analysis (principal component analysis, PCA) to detect outlier samples, recognise patterns, and identify important variables. Based on patients' laboratory tests results, machine learning models were implemented to predict disease positivity and severity. Artificial neural networks (ANN), decision trees (DT), partial least squares discriminant analysis (PLS-DA), and K nearest neighbour algorithm (KNN) models were used. The four models were validated based on the accuracy (area under the ROC curve). Results: The first subset of data had 5,643 patient samples (5,086 negatives and 557 positives for COVID-19). The second subset included 557 COVID-19 positive patients. The ANN, DT, PLS-DA, and KNN models allowed the classification of negative and positive samples with > 84% accuracy. It was also possible to classify patients with severe and non-severe disease with an accuracy > 86%. The following were associated with the prediction of COVID-19 diagnosis and severity: hyperferritinaemia, hypocalcaemia, pulmonary hypoxia, hypoxemia, metabolic and respiratory acidosis, low urinary pH, and high levels of lactate dehydrogenase. Conclusion: Our analysis shows that all the models could assist in the diagnosis and prediction of COVID-19 severity.

关键词： High fat diet   Obesity   Hippocampus   BDNF   C-Fos  

摘要： Objective: Obesity, which has become one of the main health problems, results from irregular and unhealthy nutrition. In particular, an increase in the intake of high-fat foods leads to obesity and associated disorders. It is noteworthy to specify that obese individuals have memory problems. This study aims to examine the effects of high-fat diet on hippocampus, with stereological, histopathological methods and STRING bioinformatic tool. Methods: Female Adult Sprague Dawley rats (n = 20) were equally divided into control (CONT) and high-fat diet (HFD) groups. The control group was given standard rat pellet feed, while the high-fat diet group was fed with a 40 % fat content for 2 months. Following the feeding program, rats were sacrificed. The collected blood samples were analyzed biochemically to determine the level of oxidative stress while performing a stereological and histopathological examination of the brain tissues. Functional protein-protein networks for BDNF, C-Fos, CAT, LPO, SOD and MPO by gene ontology (GO) enrichment analysis were evaluated. Findings: The number of neurons decreased in the HFD group compared to the CONT group. Damage to the histological structure of the hippocampus region;such as degenerate neurons, damaged mitochondria and extended cisterns of the endoplasmic reticulum was observed. Although C-Fos level and oxidative stress parameters increased in HFD group, BDNF level decreased. While BDNF and C-Fos were observed in pathways related to neuron death, oxidative stress and memory, BDNF was pronounced in the mitochondria, and C-Fos in the endoplasmic reticulum. Discussion: This study shows that changes in both BDNF and C-Fos levels in obesity due to high-fat diet increase oxidative stress and cause neuron damage in the hippocampus.

关键词： Forensic medicine   Hemolysis   Postmortem biochemistry   Postmortem serum   IgE   Electrochemiluminescent immunoassay  

摘要： Forensic diagnosis of anaphylactic shock is a challenging task in forensic practice due to the lack of characteristic morphological changes. Postmortem analysis of serum IgE can provide helpful information for determining anaphylaxis. However, postmortem serum always suffers from hemolysis. To investigate the interference of hemolysis on postmortem analysis of total IgE by electrochemiluminescent immunoassay (ECLIA) and verify the suitability of the commercially available ECLIA kit for postmortem hemolyzed blood with the dilution-correction method, different levels of hemolyzed serum were prepared to evaluate the interference of hemolysis. A linear regression analysis was then performed on the concentration of total IgE in the completely hemolyzed blood and the corresponding serum. Our results indicated that hemolysis negatively interfered with the total IgE analysis by ECLIA and the interference (|Bias%|) increased with increasing levels of hemolysis. After controlling for |Bias%| by dilution, the test concentration of total IgE in the completely hemolyzed blood was still significantly lower than that in the serum (P < 0.05) and resulted in eight false-negative cases. A strong correlation was observed between the test concentration of total IgE in the completely hemolyzed blood and that in the serum (r = 0.983). After correction by the regression formula, the corrected concentration revealed no significant differences and exhibited the same diagnostic ability, compared with the serum total IgE concentration. These results indicate that the completely hemolyzed blood is not recommended for postmortem analysis of total IgE directly. The dilution-correction method might have potential utility in forensic practice for evaluating serum total IgE concentrations.

关键词： Stable microtubule   Labile microtubule   Tubulin   Microtubule-associated proteins   Brain   Tau  

摘要： Microtubules form a major cytoskeleton and exhibit dynamic instability through the repetitive polymerization/depolymerization of tubulin dimers. Although microtubule stability should be precisely controlled to maintain various cellular functions, it has been difficult to assess its status in vivo. Here, we propose a tubulin fractionation method reflecting the stability of microtubules in mouse tissues. Analyses of tubulin fractionated by two-step of ultracentrifugation demonstrated three distinct pools of tubulin, that appeared to be stable microtubule, labile microtubule, and free tubulin. Using this method, we were able to show the specific binding of different microtubule-associated proteins onto each pool of microtubules. Also, there were clear differences in the population of stable microtubule among tissues depending on the proliferative capacity of the constituent cells. These findings indicate that this method is useful for broad analysis of microtubule stability in physiological and pathological conditions. (c) 2021 Elsevier Inc. All rights reserved.