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关键词： hydroxyl radicals   myofibrillar protein   protein oxidation   Pseudosciaena crocea  

摘要： The oxidative modification effect of hydroxyl radicals generated by an H2O2 oxidative solution on the biochemical and functional characteristics of myofibrillar protein (MP) from large yellow croaker (Pseudosciaena crocea) was investigated. The results showed that MP of large yellow croakers was vulnerable to hydroxyl radicals. Incubation of MP with increased concentration of H2O2 led to the gradual formation of carbonyl derivatives, disulphide bonds and dityrosine, and loss of available lysine, sulphydryl, and free ammonia. Surface hydrophobicity increased, while tryptophan residues decreased, indicating a conformational transition of MP. SDS-PAGE demonstrated that both disulphide and nondisulphide bonds were involved in MP aggregation. The MP functionalities were also affected by hydroxyl radicals, including reduced solubility, gelling, and emulsifying properties. Mild oxidation (0.1 mM H2O2) slightly improved MP gel strength and water-holding capacity, while excessive oxidation caused a reduction in gel properties. The results suggested that the MP oxidation should be controlled. Practical applicationsProtein oxidation mediated by hydroxyl radicals is one of the most crucial reasons affecting the quality of large yellow croaker during processing and storage. Additionally, it is well known that the quality of protein in fish systems directly determines the quality stability and nutritional value of the fish products. Hence, the study explored how the hydroxyl radicals influenced the physicochemical and functional properties of fish MP. The changes in amino acid residues (carbonyl, available lysine, sulphydryl, free ammonia, tryptophan residues, etc.) of MP and its gelling and emulsifying properties after oxidation not only benefit the awareness of quality deterioration and quality control of large yellow croaker, but also provide a basis for the understanding of protein oxidation on the nutritional value of aquatic products and human health.

摘要： Corrigendum to 'Biochemical and Biophysical characterization of curcumin binding to human mitotic kinesin Eg5: Insights into the inhibitory mechanism of curcumin on Eg5' [Int. J. Biol. Macromol. 9 Curcumin potentiated the mitotic arrest and monopolar spindle formation in HeLa cells in synergism with monastrol. Cells exhibiting monopolar spindles upon treatment with mentioned concentrations of the drugs were counted by visualizing the centrosomes, DNA and microtubules. [Extracted from the article]

关键词： quality assurance   quality control   quality goal index   root cause analysis   Six Sigma  

摘要： Background Six Sigma methodology with a zero-defect goal has long been applied in commercial settings and was utilized in this study to assure/improve the quality of various analytes. Methods Daily internal quality control (QC) and external quality assessment data were collected and analyzed by calculating the sigma (sigma) values for 19 analytes based on the coefficient of variation, bias, and total error allowable. Standardized QC sigma charts were established with these parameters. Quality goal index (QGI) analysis and root cause analysis (RCA) were used to discover potential problems for the analytes. Results Five analytes with sigma >= 6 achieved world-class performance, and only the Westgard rule (1(3s)) with one control measurement at two QC material levels (N2) per QC event and a run size of 1000 patient samples between QC events (R1000) was needed for QC. In contrast, more control rules (2(2s)/R-4s/4(1s)) along with high N values and low R values were needed for quality assurance for five analytes with 4 <= sigma < 6. However, the sigma levels of nine analytes were sigma < 4 at one or more QC levels, and a more rigorous QC procedure (1(3s)/2(2s)/R-4s/4(1s)/8(x) with N4 and R45) was implemented. The combination of QGI analysis and RCA further revealed inaccuracy or imprecision problems for these analytes with sigma < 4 and discovered five aspects of potential causes considered for quality improvement. Conclusions Six Sigma methodology is an effective tool for evaluating the performance of biochemical analytes and is conducive to quality assurance and improvement.

关键词： Post-translational modifications   Stem cells  

摘要： Research of the past view years expanded our understanding of the various physiological functions the cell-fate determining transcription factor SOX2 exerts in ontogenesis, reprogramming, and cancer. However, while scientific reports featuring novel and exciting aspects of SOX2-driven biology are published in near weekly routine, investigations in the underlying protein-biochemical processes that transiently tailor SOX2 activity to situational demand are underrepresented and have not yet been comprehensively summarized. Largely unrecognizable to modern array or sequencing-based technology, various protein secondary modifications and concomitant function modulations have been reported for SOX2. The chemical modifications imposed onto SOX2 are inherently heterogeneous, comprising singular or clustered events of phosphorylation, methylation, acetylation, ubiquitination, SUMOylation, PARPylation, and O-glycosylation that reciprocally affect each other and critically impact SOX2 functionality, often in a tissue and species-specific manner. One recurring regulatory principle though is the canonical PI3K/AKT signaling axis to which SOX2 relates in various entangled, albeit not exclusive ways. Here we provide a comprehensive review of the current knowledge on SOX2 protein modifications, their proposed relationship to the PI3K/AKT pathway, and regulatory influence on SOX2 with regards to stemness, reprogramming, and cancer.

关键词： body composition   dietary protein requirement   digestive enzyme activity   growth performance   Monopterus albus   serum biochemistry  

摘要： A 12-week feeding trial was conducted to determine the influence of dietary protein levels on growth performance, body composition, haematological parameters and digestive enzyme activity of Chinese rice field eel (Monopterus albus) fingerlings. Six isolipidic experimental diets (27.89%, 32.23%, 35.95%, 40.06%, 43.31% and 46.53%) were formulated to randomly assign to triplicate groups of 50 rice field eel fingerlings (5.0 +/- 0.5 g) cultured in plastic cages. Results indicated that the best growth performance of fish with the highest WG (158.68 +/- 31.59%) and SGR (2.28 +/- 0.21%) was obtained at 40.06% group. Significant alterations were demonstrated on whole-body crude protein, crude lipid and amino acid profile by different dietary protein levels. Besides, haematological parameters including triacylglycerol, aspartate aminotransferase and alkaline phosphatase decreased with various levels by the increasing of dietary protein levels. The lowest pepsin activity was observed in 27.89% protein group, which suggested lower availability of protein as substrate for protease activity. Meanwhile, the highest amylase activity in fish of 27.89% group indicated higher carbohydrate level in this group. Based on the polynomial regression analysis of WG and SGR, the dietary protein requirement for fingerlings of Monopterus albus was estimated to be 386.4-390.8 g/kg, respectively, with the lipid level of 10.08%.

ISBN: (纸本)9787030633521

关键词： functional traits   literature survey   sugi   hinoki   Japanese cypress   Japanese cedar   allocation   photosynthesis   respiration   water relation  

摘要： Cryptomeria japonica (sugi) and Chamaecyparis obtusa (hinoki) are major Japanese timber species whose plantation area accounts for 44 and 25%, respectively, of the plantation forests in Japan. Physiology, anatomy and ecology of the species have been intensively studied for this half century, which now forms a huge stock of information. These data, however, were scattered in diverse sources, including papers, bulletins of research institutes, reports of other kinds and books, and were presented in nonstandardized, diverse styles in each source. This paper provides a database (SugiHinoki DB) that compiles 177 plant traits of sugi and hinoki from 364 primary sources published since 1950. The compiled traits include physiological, morphological, anatomical and biochemical features that are recognized as relevant to life history strategies, vegetation modeling and global change responses. Collected data have been obtained under different environmental conditions, for plants with different ages and for organs with a different age or different position, which provide information of within-species variation for a given trait. Each data entry is accompanied by detailed ancillary information describing the site of measurement, stand of measurement and detailed measurement conditions, which help users account for data variations as a consequence of phenotypic plasticity and genetic variations and to filter data. To provide data in a consistent format, the data and the ancillary information were standardized, and units were converted. After data compilation, outliers were detected by calculating interquartile range for each trait per each species. As of August 2019, SugiHinokiDB contains 24,683 data entries (16,410 for sugi, 8,273 for hinoki). As sugi and hinoki are major plantation species in Japan, the data mostly came from study sites in Japan (from Hokkaido in the north to Yakushima island in Kyushu to the south) but were also obtained from arboretums or plantation forests

关键词： Electromagnetic field   Immunohistochemistry   Superoxide dismutase   Thymoquinone   Rat   Testis  

摘要： Long-term use of cell phones emitting electromagnetic fields (EMFs) have raised concerns regarding public health in recent year. We aimed to investigate the possible effects of 900 MHz EMF exposure (60 min/day for 28 days) on the rat testis. Another objective was to determine whether the deleterious effect of EMF radiation would be reduced by the administration of thymoquinone (TQ) (10 mg/kg/day). Twenty-four male adult Wistar albino rats were randomly selected, then assigned into four groups as followControl, EMF, TQ and EMF + TQ. Testicular samples were analyzed using histological, stereological, biochemical and immunohistochemical techniques. Total numbers of primary spermatocytes and spermatids as well as Leydig cells were significantly decreased in the EMF group compared to the Control group (p < 0.05). In the EMF + TQ group, the total number of primary spermatocytes was significantly increased compared to the EMF group (p < 0.05). Superoxide dismutase (SOD) activity was significantly increased in the EMF group compared to the Control group (p< 0.05). Also, serum testosterone levels and wet weight of testes were significantly decreased in the EMF group compared to the Control group (p < 0.05). Our findings suggested that exposure to a 900 MHz EMF had adverse effects on rat testicular tissue and that the administration of TQ partially mitigated testicular oxidative damages caused by EMF radiation.

关键词： Azospirillum brasilense Cd   Arsenic   Biofilm   Exopolymers   ars operon   Arsenic transformation  

摘要： Azospirillum brasilense Cd is a bacterial strain widely used as an inoculant of several crops due to its plant growth promoting properties. However, its beneficial effects depend on its viability and functionality under adverse environmental conditions, including the presence of arsenic (As) in agricultural soils. Therefore, the aim of this work was to evaluate the response of A. brasilense Cd to arsenate (AsV) and arsenite (AsIII). This bacterium was tolerant to As concentrations frequently found in soils. Moreover, properties related to roots colonization (motility, biofilm, and exopolymers) and plant growth promotion (auxin, siderophore production, and N-2 fixation) were not significantly affected by the metalloid. In order to deepen the understanding on As responses of A. brasilense Cd, As resistance genes were sequenced and characterized for the first time in this work. These genes could mediate the redox As transformation and its extrusion outside the cell, so they could have direct association with the As tolerance observed. In addition, its As oxidation/reduction capacity could contribute to change the AsV/AsIII ratio in the environment. In conclusion, the results allowed to elucidate the As response of A. brasilense Cd and generate interest for its potential use in polluted environments.

关键词： Health   Stress   Starvation   Plasma   Blood biochemistry   Body weight  

摘要： In this study, we analyzed biochemical parameters and the body masses of 14 incubating Common Eiders (Somateria mollissima) breeding on Christianso in the Baltic Sea from April to May 2015. The eiders were examined and sampled on days 4 and 24, corresponding to early and late incubation. In comparison to reference values, concentrations of alkaline phosphatase (161%), phosphorus (33%), and calcium (44%) were all significantly increased on day 4 by 33-161% due to egg production (p < 0.05). On day 24, we observed a significant loss of body mass (28%) compared to day 4 (p < 0.05). The average plasma concentrations of fructosamine (1-amino-1-deoxy-d-fructose, 21%), amylase (54%), albumin (30%), and total protein declined significantly (all p < 0.05). These declines resemble those seen for other avian species in which the female is the sole incubator, suggesting reduced food intake during the incubation period. A decline in total protein and albumin from day 4 to day 24 (18-30%) is indicative of stage III protein metabolism. Nonetheless, stable concentrations of urea, sodium, and potassium suggest that the incubating females were significantly hydrated. The change in the plasma albumin:globulin ratio from day 4 (0.82) to day 24 (0.57) may imply slight immune suppression, which is supported by the observation of a mass mortality incident shortly after the studied incubation period. These biochemical observations may add to our understanding of the recurrent mortality events that strike without warning in the declining Baltic eider population.