Apigenin protects against ischemic stroke by increasing DNA repair.

Background and Objective: Oxidative stress is an important pathological process in ischemic stroke (IS). Apigenin (APG) is a natural product with favorable antioxidative effects, and some studies have already demonstrated the antioxidative mechanism of APG in the treatment of IS. However, the mechanism of APG on DNA damage and repair after IS is not clear. The aim of this study was to investigate the mechanism of APG on DNA repair after IS. Methods: Male Sprague-Dawley rats were used to establish a model of permanent middle cerebral artery occlusion (pMCAO) on one side, and were pre-treated with gavage of APG (30, 60, or 120 mg/kg) for 7 days. One day after pMCAO, the brain tissues were collected. Cerebral infarct volume, brain water content, HE staining and antioxidant index were analyzed to evaluated the brain damage. Molecular Docking, molecular dynamics (MD) simulation, immunohistochemistry, and Western blot were used to explore the potential proteins related to DNA damage repair. Results: APG has a low binding score with DNA repair-related proteins. APG treatment has improved the volume of cerebral infarction and neurological deficits, reduced brain edema, and decreased parthanatos and apoptosis by inhibiting PARP1/AIF pathway. In addition, APG improved the antioxidative capacity through reducing reactive oxygen species and malondialdehyde, and increasing glutathione and superoxide dismutase. Also, APG has reduced DNA damage- and cell death-related proteins such as PARP1, γH2A.X, 53BP1, AIF, cleaved caspase3, Cytochrome c, and increased DNA repair by BRCA1 and RAD51 through homologous recombination repair, and reduced non-homologous end link repair by KU70. Conclusion: APG can improve nerve damage after IS, and these protective effects were realized by reducing oxidative stress and DNA damage, and improving DNA repair.

Antioxidant Dipeptides Enhance Osmotic Stress Tolerance by Regulating the Yeast Cell Wall and Membrane.

This study aimed to investigate the role of the yeast cell wall and membrane in enhancing osmotic tolerance by antioxidant dipeptides (ADs) including Ala-His (AH), Thr-Tyr (TY), and Phe-Cys (FC). Results revealed that ADs could improve the integrity of the cell wall by restructuring polysaccharide structures. Specifically, FC significantly (p < 0.05) reduced the leakage of nucleic acid and protein by 2.86% and 5.36%, respectively, compared to the control. In addition, membrane lipid composition played a crucial role in enhancing yeast tolerance by ADs, including the increase of cell membrane integrity and the decrease of permeability by regulating the ratio of unsaturated fatty acids. The up-regulation of gene expression associated with the cell wall integrity pathway (RLM1, SLT2, MNN9, FKS1, and CHS3) and fatty acid biosynthesis (ACC1, HFA1, OLE1, ERG1, and FAA1) further confirmed the positive impact of ADs on yeast tolerance against osmotic stress.

Surgical prediction of neonatal necrotizing enterocolitis based on radiomics and clinical information.

PURPOSE: To assess the predictive value of radiomics for surgical decision-making in neonatal necrotizing enterocolitis (NEC) when abdominal radiographs (ARs) do not suggest an absolute surgical indication for free pneumoperitoneum. METHODS: In this retrospective study, we finally included 171 newborns with NEC and obtained their ARs and clinical data. The dataset was randomly divided into a training set (70%) and a test set (30%). We developed machine learning models for predicting surgical treatment using clinical features and radiomic features, respectively, and combined these features to build joint models. We assessed predictive performance of the different models by receiver operating characteristic curve (ROC) analysis and compared area under curve (AUC) using the Delong test. Decision curve analysis (DCA) was used to assess the potential clinical benefit of the models to patients. RESULTS: There was no significant difference in AUC between the clinical model and the four radiomic models (P > 0.05). The XGBoost joint model had better predictive efficacy and stability (AUC, training set: 0.988, test set: 0.959). Its AUC in the test set was significantly higher than that of the clinical model (P < 0.05). DCA showed that the XGBoost joint model achieved higher net clinical benefit compared to the clinical model in the threshold probability range (0.2-0.6). CONCLUSION: Radiomic features based on AR are objective and reproducible. The joint model combining radiomic features and clinical signs has good surgical predictive efficacy and may be an important method to help primary neonatal surgeons assess the surgical risk of NEC neonates.

Mechanism of selenite tolerance during barley germination: A combination of tissue selenium metabolism alterations and ascorbate-glutathione cycle modulation.

Selenite is widely used to increase Selenium (Se) content in cereals, however excessive selenite may be toxic to plant growth. In this study, barley was malted to elucidate the action mechanism of selenite in the generation and detoxification of oxidative toxicity. The results showed that high doses (600 µM) of selenite radically increased oxidative stress by the elevated accumulation of superoxide and malondialdehyde, leading to phenotypic symptoms of selenite-induced toxicity like stunted growth. Barley tolerates selenite through a combination of mechanisms, including altering Se distribution in barley, accelerating Se efflux, and increasing the activity of some essential antioxidant enzymes. Low doses (150 µM) of selenite improved barley biomass, respiratory rate, root vigor, and maintained the steady-state equilibrium between reactive oxygen species (ROS) and antioxidant enzyme. Selenite-induced proline may act as a biosignal to mediate the response of barley to Se stress. Furthermore, low doses of selenite increased the glutathione (GSH) and ascorbate (AsA) concentrations by mediating the ascorbate-glutathione cycle (AsA-GSH cycle). GSH intervention and dimethyl selenide volatilization appear to be the primary mechanisms of selenite tolerance in barley. Thus, results from this study will provide a better understanding of the mechanisms of selenite tolerance in crops.

Pneumonia, lymphocytes and C-reactive protein are valuable tests for predicting surgical intervention in necrotizing enterocolitis.

Background: Necrotizing enterocolitis (NEC) is one of the important causes of neonatal death, and proper timing of operation is of critical significance. This study aimed to explore the high-risk factors for NEC requiring surgical intervention and to provide a reference for its clinical diagnosis and treatment. Methods: Clinical and radiological evidence of NEC neonates admitted to Zhujiang Hospital of Southern Medical University and Zhongshan Boai Hospital from January 2010 to October 2022 were retrospectively analyzed. Patients were divided into surgical group and conservative group according to whether they underwent surgery or not. Univariate analysis of the clinical data of the two groups was conducted, and multivariate logistic regression analysis was then performed for statistically significant results in the univariate analysis. Results: 267 infants were included in this study, of which 90 patients underwent surgical intervention for NEC and 177 conservation treatment. The univariate analysis showed that the gestational age, pneumonia, leukocytes, lymphocytes, erythrocytes, platelets, C-reactive protein, and blood glucose were statistically significant in the surgical group compared to the conservative group (All P < 0.05). Furthermore, the results of multivariate logistic regression analysis showed that compared to the conservative group, patients in the surgical group had a higher proportion of pneumonia (OR = 2.098; 95% CI: 1.030-4.272; P = 0.041), lower lymphocyte values (OR = 0.749; 95% CI: 0.588-0.954; P = 0.019), and higher C-reactive protein values (OR = 1.009; 95% CI: 1.003-1.016; P = 0.004). Conclusions: Pneumonia, decreased lymphocytes, and elevated C-reactive protein are potential high-risk factors for neonates with NEC requiring surgical intervention and may have potential clinical implications for predicting surgical risk.

Mechanisms of Antioxidant Dipeptides Enhancing Ethanol-Oxidation Cross-Stress Tolerance in Lager Yeast: Roles of the Cell Wall and Membrane.

High concentrations of ethanol could cause intracellular oxidative stress in yeast, which can lead to ethanol-oxidation cross-stress. Antioxidant dipeptides are effective in maintaining cell viability and stress tolerance under ethanol-oxidation cross-stress. In this study, we sought to elucidate how antioxidant dipeptides affect the yeast cell wall and membrane defense systems to enhance stress tolerance. Results showed that antioxidant dipeptide supplementation reduced cell leakage of nucleic acids and proteins by changing cell wall components under ethanol-oxidation cross-stress. Antioxidant dipeptides positively modulated the cell wall integrity pathway and up-regulated the expression of key genes. Antioxidant dipeptides also improved the cell membrane integrity by increasing the proportion of unsaturated fatty acids and regulating the expression of key fatty acid synthesis genes. Moreover, the addition of antioxidant dipeptides significantly (p < 0.05) increased the content of ergosterol. Ala-His (AH) supplementation caused the highest content of ergosterol, with an increase of 23.68 ± 0.01% compared to the control, followed by Phe-Cys (FC) and Thr-Tyr (TY). These results revealed that the improvement of the cell wall and membrane functions of antioxidant dipeptides was responsible for enhancing the ethanol-oxidation cross-stress tolerance of yeast.

Proteomic analysis reveals the adaptation of Vibrio splendidus to an iron deprivation condition.

Vibrio splendidus is a ubiquitous Gram-negative marine bacterium that causes diseases within a wide range of marine cultured animals. Since iron deprivation is the frequent situation that the bacteria usually encounter, we aimed to explore the effect of iron deprivation on the proteomic profile of V. splendidus in the present study. There were 425 differentially expressed proteins (DEPs) responded to the iron deprivation condition. When the cells were grown under iron deprivation condition, the oxidation‒reduction processes, single-organism metabolic processes, the catalytic activity, and binding activity were downregulated, while the transport process, membrane cell component, and ion binding activity were upregulated, apart from the iron uptake processes. Kyoto Encyclopedia of Genes and Genomes analysis showed that various metabolism pathways, biosynthesis pathways, energy generation pathways of tricarboxylic acid cycle, and oxidative phosphorylation were downregulated, while various degradation pathways and several special metabolism pathways were upregulated. The proteomic profiles of cells at a OD600 ≈ 0.4 grown under iron deprivation condition showed high similarity to that of the cells at a OD600 ≈ 0.8 grown without iron chelator 2,2'-bipyridine. Correspondingly, the protease activity, the activity of autoinducer 2 (AI-2), and indole content separately catalyzed by LuxS and TnaA, were measured to verify the proteomic data. Our present study gives basic information on the global protein profiles of V. splendidus grown under iron deprivation condition and suggests that the iron deprivation condition cause the cell growth enter a state of higher cell density earlier. KEY POINTS: • Adaptation of V. splendidus to iron deprivation was explored by proteomic analysis. • GO and KEGG of DEPs under different iron levels or cell densities were determined. • Iron deprivation caused the cell enter a state of higher cell density earlier.

Structure, chemical stability and antioxidant activity of melanoidins extracted from dark beer by acetone precipitation and macroporous resin adsorption.

Melanoidins contribute to the sensory and functional properties of dark beers. The structure, stability, and antioxidant activity of acetone precipitation extracted melanoidins (APE-M) and macroporous resin adsorption extracted melanoidins (MAE-M) from dark beer were investigated. The structural properties of melanoidins were characterized using Fourier transform infrared spectroscopy (FTIR), circular dichroism (CD), scanning electron microscopy (SEM), and the solution storage stability, thermal behavior and antioxidant activity of melanoidins in dark beers were evaluated. MAE-M revealed more sophisticated structures than APE-M, including more concrete characteristics of Maillard reaction (MR) products in FTIR (1550-1500 cm-1), more ordered secondary structure in CD spectra, and thinner slices as well as more microspheres in SEM. The solution storage stability assay showed that certain factors, including 55 °C, 5 % v/v ethanol, UV light, and H2O2 solution, accelerated the degradation of melanoidins. The moderate extraction process of MAE-M performed a minor enthalpy change (-92.28 Jg-1) in the DSC-TG test than that of APE-M (-319.41 Jg-1). Furthermore, the ABTS and DPPH radical scavenging activities and the FRAP assay demonstrated that the antioxidant activity of MAE-M was almost twice that of APE-M. In general, MAE was more effective in extracting beer melanoidins while maintaining its accurate structure and profitable antioxidant activity than APE.

[Analysis of variant of GLI3 gene in a child featuring autosomal dominant Pallister-Hall syndrome].

OBJECTIVE: To explore the clinical and genetic characteristics of a child with Pallister-Hall syndrome (PHS). METHODS: DNA was extracted from peripheral blood sample from the child and subjected to whole exome sequencing. Suspected variants were verified by Sanger sequencing of his family members. RESULTS: Genetic testing revealed that the child has harbored a heterozygous c.3320_3330delGGTACGAGCAG (p.G1107Afs×18) variant of the GLI3 gene. Neither parent was found to carry the same variant. CONCLUSION: The c.3320_3330delGGTACGAGCAG (p.G1107Afs×18) frameshift variant of the GLI3 gene probably underlay the pathogenesis of PHS in this child. Genetic testing should be considered for patients featuring hypothalamic hamartoma and central polydactyly.

Protective effects of peptides on the cell wall structure of yeast under osmotic stress.

Three peptides (LL, LML, and LLL) were used to examine their influences on the osmotic stress tolerance and cell wall properties of brewer's yeast. Results suggested that peptide supplementation improved the osmotic stress tolerance of yeast through enhancing the integrity and stability of the cell wall. Transmission electron micrographs showed that the thickness of yeast cell wall was increased by peptide addition under osmotic stress. Additionally, quantitative analysis of cell wall polysaccharide components in the LL and LLL groups revealed that they had 27.34% and 24.41% higher chitin levels, 25.73% and 22.59% higher mannan levels, and 17.86% and 21.35% higher ß-1,3-glucan levels, respectively, than the control. Furthermore, peptide supplementation could positively modulate the cell wall integrity pathway and up-regulate the expressions of cell wall remodeling-related genes, including FKS1, FKS2, KRE6, MNN9, and CRH1. Thus, these results demonstrated that peptides improved the osmotic stress tolerance of yeast via remodeling the yeast cell wall and reinforcing the structure of the cell wall. KEY POINTS: • Peptide supplementation improved yeast osmotic stress tolerance via cell wall remodeling. • Peptide supplementation enhanced cell wall thickness and stability under osmotic stress. • Peptide supplementation positively modulated the CWI pathway under osmotic stress.

Improved osmotic stress tolerance in brewer's yeast induced by wheat gluten peptides.

The influences of three wheat gluten peptides (WGP-LL, WGP-LML, and WGP-LLL) on the osmotic stress tolerance and membrane lipid component in brewer's yeast were investigated. The results demonstrated that the growth and survival of yeast under osmotic stress were enhanced by WGP supplementation. The addition of WGP upregulated the expressions of OLE1 (encoded the delta-9 fatty acid desaturase) and ERG1 (encoded squalene epoxidase) genes under osmotic stress. At the same time, WGP addition enhanced palmitoleic acid (C16:1) content, unsaturated fatty acids/saturated fatty acids ratio, and the amount of ergosterol in yeast cells under osmotic stress. Furthermore, yeast cells in WGP-LL and WGP-LLL groups were more resistant to osmotic stress. WGP-LL and WGP-LLL addition caused 25.08% and 27.02% increase in membrane fluidity, 22.36% and 29.54% reduction in membrane permeability, 18.38% and 14.26% rise in membrane integrity in yeast cells, respectively. In addition, scanning electron microscopy analysis revealed that the addition of WGP was capable of maintaining yeast cell morphology and reducing cell membrane damage under osmotic stress. Thus, alteration of membrane lipid component by WGP was an effective approach for increasing the growth and survival of yeast cells under osmotic stress. KEY POINTS: •WGP addition enhanced cell growth and survival of yeast under osmotic stress. •WGP addition increased unsaturated fatty acids and ergosterol contents in yeast. •WGP supplementation improved membrane homeostasis in yeast at osmotic stress.

Wheat Gluten Peptides Enhance Ethanol Stress Tolerance by Regulating the Membrane Lipid Composition in Yeast.

Wheat gluten peptides (WGPs), identified as Leu-Leu (LL), Leu-Leu-Leu (LLL), and Leu-Met-Leu (LML), were tested for their impacts on cell growth, membrane lipid composition, and membrane homeostasis of yeast under ethanol stress. The results showed that WGP supplementation could strengthen cell growth and viability and enhance the ethanol stress tolerance of yeast. WGP supplementation increased the expressions of OLE1 and ERG1 and enhanced the levels of oleic acid (C18:1) and ergosterol in yeast cell membranes. Moreover, LLL and LML exhibited a better protective effect for yeast under ethanol stress compared to LL. LLL and LML supplementation led to 20.3 ± 1.5% and 18.9 ± 1.7% enhancement in cell membrane fluidity, 21.8 ± 1.6% and 30.5 ± 1.1% increase in membrane integrity, and 26.3 ± 4.8% and 27.6 ± 4.6% decrease in membrane permeability in yeast under ethanol stress, respectively. The results from scanning electron microscopy (SEM) elucidated that WGP supplementation is favorable for the maintenance of yeast cell morphology under ethanol stress. All of these results revealed that WGP is an efficient enhancer for improving the ethanol stress tolerance of yeast by regulating the membrane lipid composition.

Structure of the human RNA polymerase I elongation complex.

Eukaryotic RNA polymerase I (Pol I) transcribes ribosomal DNA and generates RNA for ribosome synthesis. Pol I accounts for the majority of cellular transcription activity and dysregulation of Pol I transcription leads to cancers and ribosomopathies. Despite extensive structural studies of yeast Pol I, structure of human Pol I remains unsolved. Here we determined the structures of the human Pol I in the pre-translocation, post-translocation, and backtracked states at near-atomic resolution. The single-subunit peripheral stalk lacks contacts with the DNA-binding clamp and is more flexible than the two-subunit stalk in yeast Pol I. Compared to yeast Pol I, human Pol I possesses a more closed clamp, which makes more contacts with DNA. The Pol I structure in the post-cleavage backtracked state shows that the C-terminal zinc ribbon of RPA12 inserts into an open funnel and facilitates "dinucleotide cleavage" on mismatched DNA-RNA hybrid. Critical disease-associated mutations are mapped on Pol I regions that are involved in catalysis and complex organization. In summary, the structures provide new sights into human Pol I complex organization and efficient proofreading.

Structure, Antioxidant Activity and In Vitro Hypoglycemic Activity of a Polysaccharide Purified from Tricholoma matsutake.

The structure, antioxidant activity and hypoglycemic activity in vitro of a novel homogeneous polysaccharide from Tricholoma matsutake (Tmp) were investigated. Structural features suggested that Tmp was consisted of arabinose (Ara), mannose (Man), glucose (Glc) and galactose (Gal) with a molar ratio of 1.9:13.6:42.7:28.3, respectively, with a molecular weight of 72.14 kDa. The structural chain of Tmp was confirmed to contain →2,5)-α-l-Arabinofuranose (Araf)-(1→, →3,5)-α-l-Araf-(1→, ß-d-Glucopyranose (Glcp)-(1→, α-d-Mannopyranose (Manp)-(1→, α-d-Galacopyranose (Galp)-(1→, →4)-ß-d-Galp-(1→, →3)-ß-d-Glcp-(1→, →3)-α-d-Manp-(1→, →6)-3-O-Methyl (Me)-α-d-Manp-(1→, →6)-α-d-Galp-(1→, →3,6)-ß-d-Glcp-(1→, →6)-α-d-Manp-(1→ residues. Furthermore, Tmp possessed strong antioxidant activity and showed the strong inhibitory effect on α-glucosidase and α-amylase activities. Then, a further evaluation found that there was a dramatic improvement in the glucose consumption, glycogen synthesis and the activities of pyruvate kinase and hexokinase when the insulin-resistant-human hepatoma cell line (IR-HepG2) was treated with Tmp. The above results indicated that Tmp had good hypoglycemic activity and also exhibited great potentials in in terms of dealing with type 2 diabetes mellitus.

Single-cell RNA-seq landscape midbrain cell responses to red spotted grouper nervous necrosis virus infection.

Viral nervous necrosis (VNN) is an acute and serious fish disease caused by nervous necrosis virus (NNV) which has been reported massive mortality in more than fifty teleost species worldwide. VNN causes damage of necrosis and vacuolation to central nervous system (CNS) cells in fish. It is difficult to identify the specific type of cell targeted by NNV, and to decipher the host immune response because of the functional diversity and highly complex anatomical and cellular composition of the CNS. In this study, we found that the red spotted grouper NNV (RGNNV) mainly attacked the midbrain of orange-spotted grouper (Epinephelus coioides). We conducted single-cell RNA-seq analysis of the midbrain of healthy and RGNNV-infected fish and identified 35 transcriptionally distinct cell subtypes, including 28 neuronal and 7 non-neuronal cell types. An evaluation of the subpopulations of immune cells revealed that macrophages were enriched in RGNNV-infected fish, and the transcriptional profiles of macrophages indicated an acute cytokine and inflammatory response. Unsupervised pseudotime analysis of immune cells showed that microglia transformed into M1-type activated macrophages to produce cytokines to reduce the damage to nerve tissue caused by the virus. We also found that RGNNV targeted neuronal cell types was GLU1 and GLU3, and we found that the key genes and pathways by which causes cell cytoplasmic vacuoles and autophagy significant enrichment, this may be the major route viruses cause cell death. These data provided a comprehensive transcriptional perspective of the grouper midbrain and the basis for further research on how viruses infect the teleost CNS.

The ERß-CXCL19/CXCR4-NFκB pathway is critical in mediating the E2-induced inflammation response in the orange-spotted grouper (Epinephelus coioides).

The main physiological function of 17ß-estradiol (E2) in vertebrates is to regulate sexual development and reproduction. In fish, especially hermaphroditic fish, estrogen is often used to aid reproduction, but it also can trigger an inflammatory response. However, the molecular mechanism for this E2-induced inflammatory reaction is not clear. In this study, we found that the ERß-CXCL19/CXCR4-NFκB cascade regulated the E2-induced inflammatory response in the orange-spotted grouper (Epinephelus coioides). Strikingly, E2 treatment resulted in significantly high expression of inflammatory cytokines and induced phosphorylation and degradation of IκBα and translocation of NFκB subunit p65 to the nucleus in grouper spleen cells. However, the E2-induced inflammatory response could be prevented by the broad estrogen receptor (ER) ligand ICI 182,780. Moreover, the luciferase assay showed that E2 induced the inflammatory response by activating the promotor of chemokine CXCL19 through ERß1 and ERß2. Knockdown of CXCL19 blocked the E2-induced inflammatory response and NFκB nucleus translocation. Additionally, knockdown of chemokines CXCR4a and CXCR4b together, but not alone, blocked the E2-induced inflammatory response. The immunofluorescence assay and co-immunoprecipitation analysis showed that CXCL19 mediated the E2-induced inflammatory response by activating CXCR4a or CXCR4b. Taken together, these results showed that the ERß-CXCL19/CXCR4-NFκB pathway mediated the E2-induced inflammatory response in grouper. These findings are valuable for future comparative immunological studies and provide a theoretical basis for mitigating the adverse reactions that occur when using E2 to help fish reproduce.

Structural insights into preinitiation complex assembly on core promoters.

Transcription factor IID (TFIID) recognizes core promoters and supports preinitiation complex (PIC) assembly for RNA polymerase II (Pol II)-mediated eukaryotic transcription. We determined the structures of human TFIID-based PIC in three stepwise assembly states and revealed two-track PIC assembly: stepwise promoter deposition to Pol II and extensive modular reorganization on track I (on TATA-TFIID-binding element promoters) versus direct promoter deposition on track II (on TATA-only and TATA-less promoters). The two tracks converge at an ~50-subunit holo PIC in identical conformation, whereby TFIID stabilizes PIC organization and supports loading of cyclin-dependent kinase (CDK)-activating kinase (CAK) onto Pol II and CAK-mediated phosphorylation of the Pol II carboxyl-terminal domain. Unexpectedly, TBP of TFIID similarly bends TATA box and TATA-less promoters in PIC. Our study provides structural visualization of stepwise PIC assembly on highly diversified promoters.

Peptide (Lys-Leu) and amino acids (Lys and Leu) supplementations improve physiological activity and fermentation performance of brewer's yeast during very high-gravity (VHG) wort fermentation.

Lys and Leu were generally considered as the key amino acids for brewer's yeast during beer brewing. In the present study, peptide Lys-Leu and a free amino acid (FAA) mixture of Lys and Leu (Lys + Leu) were supplemented in 24 °P wort to examine their effects on physiological activity and fermentation performance of brewer's yeast during very high-gravity (VHG) wort fermentation. Results showed that although both peptide Lys-Leu and their FAA mixture supplementations could increase the growth and viability, intracellular trehalose and glycerol content, wort fermentability, and ethanol content for brewer's yeast during VHG wort fermentation, and peptide was better than their FAA mixture at promoting growth and fermentation for brewer's yeast when the same dose was kept. Moreover, peptide Lys-Leu supplementation significantly increased the assimilation of Asp, but decreased the assimilation of Gly, Ala, Val, (Cys)2, Ile, Leu, Tyr, Phe, Lys, Arg, and Pro. However, the FAA mixture supplementation only promoted the assimilation of Lys and Leu, while reduced the absorption of total amino acids to a greater extent. Thus, the peptide Lys-Leu was more effective than their FAA mixture on the improvement of physiological activity, fermentation performance, and nitrogen metabolism of brewer's yeast during VHG wort fermentation.

The Reference Intervals for Serum C-Terminal Agrin Fragment in Healthy Individuals and as a Biomarker for Renal Function in Kidney Transplant Recipients.

BACKGROUND: C-terminal agrin fragment (CAF) has been shown to be a promising new biomarker for kidney function. The aim of this study was to verify the reference intervals for CAF in Chinese healthy adults and to assess the efficiency of CAF for monitoring renal function after transplantation. METHODS: Serum samples were collected from 200 healthy adult subjects and 60 living donor kidney recipients before and on day 1, day 2 and at 6 months after transplantation. We measured serum CAF, creatinine, cystatin C and NGAL concentrations at each time. Estimated glomerular filtration rate (eGFR) was evaluated by Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Reference intervals for CAF were determined at 2.5th and 97.5th percentiles. RESULTS: Serum CAF concentrations were observed to be higher in females of old age groups while no significant differences were discovered in males between age groups. There were significant gender-related differences in CAF in old age groups (50-64 and ≥65 years). Serum CAF correlated positively with serum creatinine, cystatin C and negatively with eGFR on day 1, day 2 and at 6 months after kidney transplantation. CAF and NGAL fell rapidly into the normal range on the second postoperative day, prior to creatinine and cystatin C. CONCLUSIONS: This study verified the reference intervals for serum CAF. CAF could be a potential new biomarker for kidney function monitoring.

Formation of diploid and triploid hybrid groupers (hybridization of Epinephelus coioides ♀ × Epinephelus lanceolatus ♂) and their 5S gene analysis.

BACKGROUND: Interspecies hybridization is widely used to achieve heterosis or hybrid vigor, which has been observed and harnessed by breeders for centuries. Natural allopolyploid hybrids generally exhibit more superior heterosis than both the diploid progenies and their parental species. However, polyploid formation processes have been long ignored, the genetic basis of heterosis in polyploids remains elusive. RESULTS: In the present study, triploid hybrids had been demonstrated to contain two sets of chromosomes from mother species and one set from father species. Cellular polyploidization process in the embryos had been traced. The triploid hybrids might be formed by failure formation of the second polarized genome during the second meiosis stage. Four spindle centers were observed in anaphase stage of the first cell division. Three spindle centers were observed in side of cell plate after the first cell division. The 5S rDNA genes of four types of groupers were cloned and analyzed. The diploid and triploid hybrids had been proved to contain the tandem chimera structures which were recombined by maternal and paternal monomer units. The results indicated that genome re-fusion had occurred in the hybrid progenies. To further elucidate the genetic patterns of diploid and triploid hybrids, fluorescence chromosome location had been carried out, maternal 5S gene (M-386) were used as the probe. The triploid hybrids contained fewer fluorescence loci numbers than the maternal species. The results indicated that participation of paternal 5S gene in the triploid hybrid genome had degraded the match rates of M-386 probe. CONCLUSIONS: Our study is the first to investigate the cellular formation processes of natural allopolyploids in hybrid fish, the cellular polyploidization process may be caused by failure formation of the second polarized genome during the meiosis, and our results will provide the molecular basis of hybrid vigor in interspecies hybridization.