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关键词： PP2A   intellectual disability   neurodevelopmental disorder   epilepsy   PROTEIN PHOSPHATASE 2A   PP2A   SUBUNIT   SPECIFICITY   PPP2R5D   DEPHOSPHORYLATION   INSIGHTS   FAMILY   CORE   TAU  

摘要： Purpose Neurodevelopmental disorders (NDD) caused by protein phosphatase 2A (PP2A) dysfunction have mainly been associated with de novo variants in PPP2R5D and PPP2CA, and more rarely in PPP2R1A. Here, we aimed to better understand the latter by characterizing 30 individuals with de novo and often recurrent variants in this PP2A scaffolding A alpha subunit. Methods Most cases were identified through routine clinical diagnostics. Variants were biochemically characterized for phosphatase activity and interaction with other PP2A subunits. Results We describe 30 individuals with 16 different variants in PPP2R1A, 21 of whom had variants not previously reported. The severity of developmental delay ranged from mild learning problems to severe intellectual disability (ID) with or without epilepsy. Common features were language delay, hypotonia, and hypermobile joints. Macrocephaly was only seen in individuals without B55 alpha subunit-binding deficit, and these patients had less severe ID and no seizures. Biochemically more disruptive variants with impaired B55 alpha but increased striatin binding were associated with profound ID, epilepsy, corpus callosum hypoplasia, and sometimes microcephaly. Conclusion We significantly expand the phenotypic spectrum of PPP2R1A-related NDD, revealing a broader clinical presentation of the patients and that the functional consequences of the variants are more diverse than previously reported.

关键词： Egg production   Heat stress   Nutritional metabolism   Organic chromium   Poultry   CARCASS TRAITS   BENEFICIAL APPLICATIONS   GROWTH-PERFORMANCE   POULTRY NUTRITION   OXIDATIVE STRESS   SUPPLEMENTATION   HENS   METABOLITES   HEALTH   FORM  

摘要： Recent studies have shown that chromium (Cr) could alleviate the negative effects of heat stress on livestock and poultry, but there is little information available to laying ducks. This study aimed to investigate the effects of dietary addition of chromium propionate on laying performance, egg quality, serum biochemical parameters and antioxidant status of laying ducks under hot (average 32 degrees C) and humid (average 75% relative humidity) summer conditions. A total of 900 66-week-old weight- and laying-matched Shanma laying ducks were randomly divided into five treatments, each with 6 replicates of 30 individually caged birds. The birds were fed either a basal diet or the basal diet supplemented with either 200, 400, 600, or 800 mu g/kg Cr as chromium propionate. All laying ducks were given feed and water ad libitum for 5 weeks. The results showed that dietary supplementation with chromium propionate significantly increased the laying rate and yolk colour score (P < 0.05). Treatment with 400 mu g/kg Cr as chromium propionate significantly decreased the feed /egg ratio by 5.4% (P < 0.05). Increased supplemental Cr from 0 to 800 mu g/kg resulted in an increase in albumen height and the Haugh unit linearly (P < 0.05). Increased supplemental Cr decreased serum cortisol (P < 0.001, linear; P 0.008, quadratic), heat shock protein-70 (P < 0.001, linear; P = 0.007, quadratic) and glucose (P = 0.007, linear), whereas it increased serum insulin (P= 0.011, Linear), total protein (P = 0.006, linear; P = 0.048, quadratic) and albumin ( P 0.035, linear; P = 0.088, quadratic). Dietary Cr levels increased the activities of superoxide dismutase and glutathione peroxidase, the total antioxidant capacity linearly and quadratically (P < 0.05). A linear and quadratic (P < 0.05) decrease of the malondialdehyde concentrations in response to dietary Cr level was observed. These results indicated that dietary supplementation of Cr as chromium propionate, particularly at 800 mu g/kg cou

关键词： Biochemical oxygen demand   Biosensor   Microbial fuel cell   Wastewater characterization  

摘要： Objectives Single-chamber air cathode microbial fuel cells (MFCs) were applied as biosensors for biochemical oxygen demand (BOD) measurement of real wastewaters with considerable suspended and/or slowly biodegradable organic content. Results The measurement method consists of batch sample injection, continuous measurement of cell voltage and calculation of total charge (Q) gained during the biodegradation of organic content. Diverse samples were analyzed: acetate and peptone samples containing only soluble readily biodegradable substrates; corn starch and milk samples with suspended and colloidal organics; real domestic and brewery wastewaters. Linear regression fitted to the Q vs. BOD5 measurement points of the real wastewaters provided high (> 0.985) R-2 values. Time requirement of the measurement varied from 1 to 4 days, depending on the composition of the sample. Conclusions Relative error of BOD measured in the MFCs comparing with BOD5 was less than 10%, thus the method might be a good basis for the development of on-site automatic BOD sensors for real wastewater samples.

关键词： EXTERNAL HYDROCEPHALUS   PROGNOSTIC-FACTORS   TURKISH CHILDREN   CNS INVOLVEMENT   SPECTRUM   FREQUENCY   SYMPTOMS   ATROPHY  

摘要： AIM: To investigate the brain magnetic resonance imaging (MRI) features of children with haemophagocytic lymphohistiocytosis (HLH) with central nervous system (CNS) involvement, and to investigate the correlation with clinical biochemical tests. MATERIAL AND METHODS: Clinical and MRI data were collected from 118 children with HLH-CNS between January 2012 and June 2019. Patients were grouped according to their MRI findings, and statistical methods were used to test for correlations between the MRI findings and biochemical variables. RESULTS: Patients were divided into three groups, including normal appearance (Group 1, 17/118), diffuse parenchymal volume loss (Group 2, 44/118), and brain parenchyma lesions (Group 3, 57/118) containing three subtypes of brain lesions and HLH-CNS complications. Comparing biochemical values among the three groups revealed a significant difference for all values (p<0.05), except for cell counts in the cerebrospinal fluid (CSF). A pairwise comparison further showed significant inter-group differences for most of the variables. Spearman's rank correlation coefficient also demonstrated that CSF cell counts (r=0.193, p=0.036), CSF microprotein content (r=0.379, p<0.001), serum aspartate aminotransferase (AST; r=0.521, p<0.001), serum lactate dehydrogenase (LDH; r=0.514, p<0.001) and activated partial thromboplastin time (APTT; r=0.326, p<0.001) correlated positively with the MRI groups, while platelet count (PLT; r=e0.633, p<0.001) and plasma fibrinogen (FIB; r=e0.258, p=0.005) correlated negatively. CONCLUSION: Classification of brain MRI findings of HLH-CNS correlates well with the results of several key biochemical tests. Brain MRI is a promising method to elucidate illness severity and clinical outcomes. (C) 2020 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

关键词： Leukemic cells   Fluorescence quenching   Apoptosis   Galactose/glucose-binding lectin   HUMAN SERUM-ALBUMIN   BAUHINIA-FORFICATA LECTIN   MOLTEN GLOBULE STATE   APOPTOSIS INDUCTION   STRUCTURAL-ANALYSIS   PURIFICATION   BINDING   SEEDS   CLASSIFICATION   LEUKEMIAS  

摘要： Egletes viscosa is a plant with therapeutic value due to its antibacterial, antinociceptive and gastroprotective properties. This study aimed to purify, characterize, and evaluate the cytotoxicity of a lectin (EgviL) from the floral capitula of E. viscosa. The lectin was isolated from saline extract through precipitation with ammonium sulfate followed by Sephadex G-75 chromatography. The molecular mass and isoelectric point (pI) of EgviL were determined as well as its temperature and pH stability. Physical-chemical parameters of interaction between EgviL and carbohydrates were investigated by fluorescence quenching and H-1 nuclear magnetic resonance (NMR). Cytotoxicity was investigated against human peripheral blood mononuclear cells (PBMCs) and neoplastic cells. EgviL (28.8 kDa, pI 5.4) showed hemagglutinating activity stable towards heating until 60 degrees C and at the pH range 5.0-7.0. This lectin is able to interact through hydrophobic and electrostatic bonds with galactose and glucose, respectively. EgviL reduced the viability of PBMCs only at the highest concentration tested (100 mu g/mL) while was toxic to Jurkat E6-1 cells with IC50 of 24.1 mu g/mL,inducing apoptosis. In summary, EgviL is a galactose/glucose-binding protein with acidic character, stable to heating and with cytotoxic effect on leukemic cells. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Sphingobium chungbukense   DJ77   Esterase   Biochemical characterization   Molecular docking analysis   ENZYMATIC-HYDROLYSIS   RATIONAL DESIGN   LIPASE   CLASSIFICATION   FAMILY   CATALYSIS   SEQUENCE   BINDING   SINGLE  

摘要： We identified three novel microbial esterase (Est1, Est2, and Est3) from Sphingobium chungbukense DJ77. Multiple sequence alignment showed the Est1 and Est3 have distinct motifs, such as tetrapeptide motif HGGG, a pentapeptide sequencemotif GXSXG, and catalytic triad residues Ser-Asp-His, indicating that the identified enzymes belong to family IV esterases. Interestingly, Est1 exhibited strong activity toward classical esterase substrates, pnitrophenyl ester of short-chain fatty acids and long-chain. However, Est3 did not exhibit any activity despite having high sequence similarity and sharing the identical catalytic active residues with Est1. Est3 only showed hydrolytic degradation activity to polycaprolactone (PCL). MOE-docking prediction also provided the parameters consisting of binding energy, molecular docking score, and molecular distance between substrate and catalytic nucleophilic residue, serine. The engineered mutEst3 has hydrolytic activity for a variety of esters ranging from p-nitrophenyl esters to PCL. In the present study, we demonstrated that MOE-docking simulation provides a valuable insight for facilitating biocatalytic performance. (c) 2020 Elsevier B.V. All rights reserved.

关键词： Cloning   Sequencing   Genetic characterization   AutoDock Vina   CELLULASE-FREE XYLANASE   THERMOSTABLE XYLANASE   PURIFICATION   CLONING   LICHENIFORMIS  

摘要： This study employed mesophilic Bacillus subtilis RTS strain isolated from soil with high xylanolytic activity. A 642 bp (xyn) xylanase gene (GenBank accession number MT677937) was extracted from Bacillus subtilis RTS and cloned in Escherichia coli BL21 cells using pET21c expression system. The cloned gene belongs to glycoside hydrolase family 11 with protein size of approximately 23 KDa. The recombinant xylanase showed optimal enzymeactivity at 60 degrees C and at pH6.5. Thermostability of recombinant xylanase was observed between the temperature range of 30-60 degrees C. Xylanase also remained stable in different concentration of various organic solvents (ethanol, butanol). This might be due to the formation of protein/organic solvent interface which prevents stripping of essential water molecules from enzyme, thus enzyme conformation and activity remained stable. Finally, the molecular docking analysis through AutoDock Vina showed the involvement of Tyr 108, Arg140 and Pro144 in protein-ligand interaction, which stabilizes this complex. The observed stability of recombinant xylanase at higher temperature and in the presence of organic solvent (ethanol, butanol) suggested possible application of this enzyme in biofuel and other industrial applications. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Lipid classes   Fatty acids   Histology   Large nuclei   Plasma biochemistry   Nutrition   SALMON SALMO-SALAR   FATTY-ACID-COMPOSITION   DIGESTIVE ENZYME-ACTIVITIES   BASS DICENTRARCHUS-LABRAX   FISH-OIL   GROWTH-PERFORMANCE   ALKALINE-PHOSPHATASE   PHOSPHOLIPID CLASSES   NUTRITIONAL-STATUS   HEPATIC TOXICITY  

摘要： The study examined the interactive effects of choline content (supplied as choline chloride salt (CC); no added CC, 3.0, or 6.0 g CC kg(-1) diet) and water temperature (16 degrees C vs 24 degrees C) on liver lipid composition, liver histology and plasma biochemistry. Liver and plasma samples were collected from juvenile yellowtail kingfish (Seriola lalandi; YTK; 156 g body weight), fed fishmeal-based practical diets, at the conclusion of an eight-week feeding experiment. The results showed that higher liver lipid content at 24 degrees C was due to greater triacylglycerol (TAG) accumulation. Liver phospholipids content remained similar regardless of CC supplementation and temperature (P > 0.05). As expected, liver phospholipids were mainly composed of phosphatidylcholine (PC); however, in most cases liver phospholipids were almost completely made up of PC. Phospholipid classes were also not significantly affected by CC supplementation and temperature. The results indicate that these lipid classes were tightly regulated in the liver of juvenile YTK. Fatty acids composition among TAG, FFA, and phospholipids fractions were different; however, within the phospholipids fraction, the long chain polyunsaturated fatty acids (LC-PUFA) proportion in the liver of YTK remained unchanged regardless of treatments. In general, histological examination did not show severe lesions in fish livers across all treatments. Fish also had significantly more hepatocytes with large nuclei at 16 degrees C than at 24 degrees C which is a response that requires further research. Plasma analytes were profoundly affected by temperature rather than by CC supplementation; however, there is no strong evidence indicating compromised health in fish reared at either temperature. This study demonstrates that fish fed fishmeal-based practical diets generally had normal looking livers; nevertheless, some liver and plasma health indicators can be affected in juvenile YTK reared at sub-optimal temperatures a

关键词： Quorum quenching probiotic   Bacillus   Performance   Survival   Asian seabass   Vibrio harveyi   DISEASE RESISTANCE   BACILLUS-CEREUS   DIETARY SUPPLEMENTATION   IMMUNE-RESPONSE   INNATE IMMUNITY   LACTOBACILLUS-ACIDOPHILUS   IMMUNOLOGICAL PARAMETERS   PARALICHTHYS-OLIVACEUS   DICENTRARCHUS-LABRAX   PATHOGENIC BACTERIA  

摘要： The use of probiotics is a promising and increasingly common strategy to maintain a healthy farming environment in an eco-friendly and sustainable manner. The goal of this study was to investigate the possible effects of dietary supplementation with autochthonous quorum quenching (QQ) probiotics on growth, digestive enzymes activity, haemato-biochemical responses, gut microbial communities and resistance against Vibrio harveyi in Asian seabass. Asian seabass (75 +/- 0.6 g and 15.5 +/- 0.3 cm) were fed with basal diet (control groups) and basal diet containing 1 x 10(9) CFU per g Bacillus thuringiensis QQ1 or Bacillus cereus QQ2 for 6 weeks. Feeding with diets supplemented with QQ probiotics for 35 days (pre-infection period) resulted in a significant (p < 0.05) alteration of the growth parameters (RGR, FCR, SGR, PER, FER and FI) and digestive enzymes activity (alpha-amylase, total protease, lipase, trypsin, alkaline phosphatase, T/C and A/T). Hematocrit (Hct) and total leucocyte count (TLC) were significantly (p < 0.05) elevated in fish fed with QQ1. Respiratory burst activity (RBA) likewise significantly (p < 0.05) increased in the probiotic groups relative to the control groups. Moreover, a significant decrease (p < 0.05) in the level of serum total cholesterol was observed in fish fed with probiotic. QQ1 and QQ2 were able to colonize the host's intestine at high number after 5 weeks. Hct and RBA in QQ1 and QQ2, globulin in QQ2 and TLC in QQ1 were significantly (p < 0.05) promoted compared to the positive control (PC) after infection with Vibrio harveyi (day 42). Serum triglycerides, cholesterol, alkaline phosphatase (ALP), alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT) and lactate dehydrogenase (LDH) were significantly (p < 0.05) lower in the probiotic treatments than the PC group after infection. QQ probionts significantly (p < 0.05) improved the cumulative survival of Asian seabass against V. harveyi. According to these findings, we suggest

关键词： Grass carp   Microbial spoilage   Biochemical changes   Amino acid deamination   Amino acid decarboxylation   Chilled storage   BIOGENIC-AMINES   SILVER CARP   FISH   TRYPTOPHANASE   PSEUDOMONAS   QUALITY   PURIFICATION   EXTRACT   ENZYME  

摘要： This study aimed to reveal amino acid deamination and decarboxylation activities of spoilage microbiota in chill stored grass carp fillets. Results showed that microbial deamination activities of umami/sweet-taste amino acids were higher than that of bitter-taste amino acids. The total deamination activity of tested amino acids decreased during the late period of storage, which inhibited the increase of ammonia in fish flesh. Microbial decarboxylation activity of ornithine was much higher than lysine and histidine, which was consistent with the rapid increase of putrescine in fish fillets. Meanwhile, putrescine could be produced in large quantities through arginine deiminase pathway of spoilage bacteria. Glucose utilization by spoilage microbiota was active during the late period of storage, which was consistent with the rapid consumption of lactate and total sugar in fish flesh. Overall, results of this study could be beneficial for revealing fish spoilage mechanisms and providing theoretical guidance for developing fish preservation technologies.