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The application of selenol-X chemistry in nucleophilic substitution and Se-Michael addition reactions for polymer chain end modification is presented. Selenol-labeled polystyrene can easily react with alkyl halides, methyl methacrylate, methyl acrylate, pentafluorostyrene, etc. The mild conditions make it attractive for the synthesis of macromonomers. The resulting polymers are analyzed and characterized by UV, size-exclusion chromatography (SEC), NMR, and matrix assisted laser desorption/ionization time of flight mass spectroscopy. [ABSTRACT FROM AUTHOR]

Diselenide-containing polymers have attracted more and more attention due to their redox sensitivity and bioapplication. In this work, a bifunctional diselenocarbonate is prepared and used to mediate the reversible addition-fragmentation chain transfer (RAFT) polymerization, producing α,ω-selenocarbonate-labeled telechelic polystyrene. Based on effective aminolysis of the terminal selenocarbonates and the followed spontaneous oxidation coupling reaction of diselenols, monoblock cyclic polystyrene linked by one diselenide bond and multiblock cyclic copolymer linked by several diselenide bonds are prepared by manipulating the concentration of α,ω-telechelic polystyrene in solution. The progress of aminolysis and the subsequent spontaneous oxidation of selenols to diselenides are monitored by UV-vis, gel permeation chromatography (GPC), and NMR characterizations, confirming the cyclic topologies of the resultant polymers (monocyclic or multiblock cyclic polymer). The monoblock cyclic or multiblock polymers show redox sensitivity, which can be converted to linear polymer by reducing or oxidizing agent. Moreover, the obtained monoblock cyclic polymer or multiblock cyclic copolymer can be transformed to each other under UV irradiation by adjusting the concentration of the cyclic polystyrene. For the first time, this work provides an alternative and promising approach to realize the topological transformation of polymers by installing multiresponsive diselenide moities into the backbone of cyclic polymer. [ABSTRACT FROM AUTHOR]

Introduction Several lines of evidence have indicated that serotonin 2 A receptor ( HTR2A) may be involved in the pathophysiology of schizophrenia. One functional polymorphism in HTR2A ( T102C) has been widely investigated; however, the results have been inconsistent. The purpose of this study was to evaluate the association between HTR2A T02C polymorphism and schizophrenia in a Chinese Han population. Methods We performed a case-control study, using an early onset sample, which may be an attractive subgroup for genetic studies. In addition, we performed a meta-analysis of the combined sample groups in Han Chinese. Results Our study, based on 385 schizophrenic patients and 399 controls, found a significant genotype-wise association of T102C and schizophrenia ( P = 0.02). After applying stratified analyses, the dominant model for T allele produced significant association ( OR = 1.60, 95% CI = 1.11-2.30, P = 0.01). In the meta-analysis including all of the published population-based association studies in Han Chinese and the present association study, the pooled genotype-wise result in a dominant model was statistically significant with a summary OR of 1.25 (95% CI = 1.04-1.50, P = 0.02). Discussion Our results suggest that the HTR2A T102C polymorphism may confer susceptibility to schizophrenia in Han Chinese. [ABSTRACT FROM AUTHOR]

Fabrication of versatile hydrogels in a facile and effective manner represents a pivotal challenge in the field of biomaterials. Herein, a novel strategy is presented for preparing on‐demand degradable hydrogels with multilevel responsiveness. By employing selenol‐dichlorotetrazine nucleophilic aromatic substitution (SNAr) to synthesize hydrogels under mild conditions in a buffer solution, the necessity of additives or posttreatments can be obviated. The nucleophilic and redox reactions between selenol and tetrazine culminate in the formation of three degradable chemical bonds—diselenide, aryl selenide, and dearomatized selenide—in a single, expeditious step. The resultant hydrogel manifests exceptional adaptability to intricate environments in conjunction with self‐healing and on‐demand degradation properties. Furthermore, the resulting material demonstrated light‐triggered antibacterial activity. Animal studies further underscore the potential of integrating metformin into Se‐Tz hydrogels under green light irradiation, as it effectively stimulates angiogenesis and collagen deposition, thereby fostering efficient wound healing. In comparison to previously documented hydrogels, Se‐Tz hydrogels exhibit controlled degradation and drug release, outstanding antibacterial activity, mechanical robustness, and bioactivity, all without the need for costly and intricate preparation procedures. These findings underscore Se‐Tz hydrogels as a safe and effective therapeutic option for diabetic wound dressings. [ABSTRACT FROM AUTHOR]

Background: Acanthopanax senticosus (AS) is a medicinal and food plant with many physiological functions, especially nerve protection. Its extract has many functional components, including polysaccharides, flavonoids, saponins, and amino acids. Our previous study indicated that AS extract protected against nerve damage caused by radiation. However, little is known about the gut‐brain axis mechanism of AS and its impact on radiation‐induced learning and memory impairment. Method: In 60Co‐γ ray‐irradiated mice, we investigated the changes in behavior, neurotransmitters and gut microbiota after different days of administration of AS extract as a dietary supplement. Results: The AS extract improved learning and memory ability in mice, and the neurotransmitter levels in the hippocampus and colon started to change from the 7th day, which accompanied changes of the gut microbiota, a decreased abundance of Helicobacter on the 7th day and an increased abundance of Lactobacillus on the 28th day. Among the marker bacteria, Ruminococcus and Clostridiales were associated with 5‐HT synthesis, and Streptococcus were associated with 5‐HT and ACH synthesis. In addition, the AS extract increased the tight junction protein, inhibited inflammation levels in colon, and even increased the relative protein expression of BDNF and NF‐κB and decreased the relative protein expression of IκBα in the hippocampus of irradiated mice. Conclusion: These results will lay the foundation for further study on the mechanism of the gut‐brain axis of AS in preventing radiation‐induced learning and memory impairment. [ABSTRACT FROM AUTHOR]

BACKGROUND: Acanthopanax senticosus, a small woody shrub of the family Araliaceae, can be used as a functional food with multiple biological activities. Eleutheroside E (EE), an important active component of A. senticosus, has significant effects on neurological diseases. However, whether EE can regulate lipid metabolism has not been reported. The brain can mediate communication between neurons and intestinal cells through long‐distance neuroendocrine signals. We speculated that EE might regulate the intestinal lipid metabolism of Caenorhabditis elegans through neuroendocrine signals. RESULTS: First, we found that EE reduced the intestinal fat content of C. elegans, without affecting development, reproduction, food intake or movement. In addition, EE significantly regulated genes and metabolites related to lipid metabolism. EE extensively affected fatty acid synthesis, β‐oxidation and lipolysis processes, and regulated the content of various fatty acid and lipid metabolism intermediates. We finally proved that EE reduced intestinal fat storage through serotonin and neuropeptide flp‐7–npr‐22 pathways in the nervous system. CONCLUSION: EE is expected to be a functional food that regulates lipid metabolism. © 2022 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Summary: In this study, a novel polysaccharide fraction (PGPIV‐1‐a) was isolated from Platycodon grandiflorum through the combination of DEAE‐52 and Sephadex G‐100 chromatography. PGPIV‐1‐a was a neutral heteropolysaccharide with an average molecular weight of about 6462 Da. PGPIV‐1‐a was composed of glucose, arabinose and mannose in the relative molar ratio of 64.79%, 31.16% and 4.05%. The main linkage types in PGPIV‐1‐a consisted of → 6)‐β‐Glcp‐(1 → and →5)‐α‐L‐Ara‐(1→. Bioactivity assay results showed that PGPIV‐1‐a significantly stimulated the proliferation of RAW264.7 cells and enhanced their phagocytic capacity in a dose‐dependent manner. In addition, treatment with higher dosage of PGPIV‐1‐a (800 μg mL−1) remarkably induced the secretion of NO, TNF‐α and IL‐6. This study provides a theoretical basis for further systematic investigation and utilisation of Platycodon grandiflorum polysaccharides. [ABSTRACT FROM AUTHOR]

The mechanism of the regulation on photosynthesis after spaceflight has not been fully understood. To learn more information about this, we conducted a series of experiments of photosystem, including photosynthetic physiological characteristics (fluorescence parameters, pigment contents), gene expression and proteomic change. We want to examine the response of rice (Oryza sativaDN416), whose seeds were placed in Bio‐Radiation Box on the ShiJian‐10(SJ‐10) recoverable satellite. Our results demonstrated that the photosynthesis capacity of plants after spaceflight declined, compared to ground control plants. Specifically, Fv/Fm is significantly reduced for 7.5%. Chlorophyll content decreased in the three growth stages of rice, trefoil, tillering and mature stages. To further analyze changes under spaceflight environment, quantitative real‐time PCR technology and isobaric tags for relative and absolute quantization (iTRAQ) labeling technology were deployed. We found that the gene expression of important subunits of key enzymes and important structures had been decreased after spaceflight. As for the results of changes in proteins, we discovered that the content of proteins related to electron transport and photosynthesis key enzyme declined. Our experiments can provide reference for further research to learn more about the effects of spaceflight on photosynthesis. [ABSTRACT FROM AUTHOR]

The article discusses study on association of cAMP response element binding protein (CREB1) and CBP genes with Alzheimer's disease in Han Chinese. It mentions no significant difference in allele and genotype frequencies between the case and control groups in either eastern China or southwestern China populations. It adds they may not play major roles in the pathophysiology of the disease.

In this study, the peptides of soy protein obtained by enzymatic digestion with proteases were analyzed for their antidiabetic, antihypertensive, and antioxidant activities. Peptides prepared with alkaline proteinase (AP) exhibited the highest α‐glucosidase inhibitory activity compared with those from papain and trypsin digestion. AP hydrolysates also exhibited dipeptidyl peptidase IV (DPP‐IV) inhibitory, angiotensin‐converting enzyme (ACE) inhibitory, and antioxidant activities. Gastrointestinal digestion of peptides enhanced α‐glucosidase, DPP‐IV, and ACE inhibitory activities compared with AP hydrolysates. AP peptides showing highest α‐glucosidase inhibitory activity were purified by anion‐exchange and size‐exclusion chromatography， and identified using tandem MS. We found three novel α‐glucosidase inhibitory peptides with sequences LLPLPVLK, SWLRL, and WLRL with IC50 of 237.43 ± 0.52, 182.05 ± 0.74, and 162.29 ± 0.74 μmol/L, respectively. Therefore, peptides hydrolyzed from soy protein are promising natural ingredients for nutraceutical applications assisting in the management of diabetes. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Bioactive casein peptides have attracted considerable attention for their applications in industry. However, there is little clarity regarding mass spectrometric profiles for peptides in enzymatic hydrolysates of casein produced under varying conditions. In this study, the compositions of the peptides from casein hydrolysates were compared for different enzyme/substrate ratio (E/S) and hydrolysis times. The toxicity, allergenicity and bioactivity of the identified peptides were assessed in silico. RESULTS: A total of 70 unique peptides were identified, and there were 28, 21, 13 and 8 peptides from αs1‐casein, αs2‐casein, β‐casein and κ‐casein respectively. The peptide number decreased with the increase in E/S and hydrolysis time. Moreover, peptides with relative molecular mass Mr ranging from 1000 to 1500 Da occupied the highest proportion of 31.43%, and almost all of the peptides showed Mr less than 5000 Da. In silico analysis showed that all of the peptides were non‐toxic and non‐allergenic, and several of them were assessed by PeptideRanker as having a relatively high likelihood of being bioactive peptides. CONCLUSIONS: Composition of the peptides in the casein hydrolysates varied with the enzymolysis conditions. This study's results may facilitate the production of target bioactive peptides by controlling E/S and hydrolysis time, which is beneficial for the application of casein peptides in the functional food industry. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: Milk protein concentrate (MPC) is a widely used material in the food industry. However, despite its widespread use, the mechanism underlying the decreased solubility of MPC that occurs during storage has not yet been clarified. In this study, the solubility changes, protein cross‐linking, and Maillard reaction and the relationships between them were investigated in modified MPC powders (MMPC) containing different concentrations of protein and/or lactose stored at 50°C for 15–45 days. The results demonstrated that both the protein and lactose contents affected solubility. The proteins interacted through hydrogen bonding, disulfide bonding, hydrophobic interactions, and nondisulphide covalent bonding, which led to cross‐linking. The Maillard reaction promoted protein cross‐linking and was in turn influenced by protein cross‐linking. The Maillard reaction was slower when the degree of protein cross‐linking was greater. These results improve our understanding of the mechanism leading to poor solubility of MPC powders during storage. [ABSTRACT FROM AUTHOR]

In this study, we examined whether common variants in the G protein-coupled receptor kinase 6 gene ( GRK6) confers susceptibility to schizophrenia in Chinese. We genotyped two common variants in 697 schizophrenia patients and 563 healthy control subjects. No significant difference in either allele or genotype comparisons between the case and control groups was found. Our results imply that GRK6 may not play a role in the pathophysiology of schizophrenia among Han Chinese. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]