Modified bone marrow mesenchymal stem cells derived exosomes loaded with MiRNA ameliorates non-small cell lung cancer.

The study aimed to reveal the function of LXY30 peptide-modified bone marrow mesenchymal stem cell-derived exosomes (LXY30-Exos) in NSCLC. LXY30 peptide is a peptide ligand targeting α3ß1 integrin, and LXY30 specifically binds to Exos derived from different cells. We use transmission electron microscopy to identify LXY30-Exos and tracking analysis for particles, and the LXY30-Exos internalized by NSCLC cells in vitro and targeted NSCLC tumours in vivo were verified by multiple molecular technologies. The functions of LXY30-Exos-encapsulated miR-30c, miR-181b or miR-613 were assessed using cell proliferation, migration and cell apoptosis assays. Meanwhile, the safety of the above engineered Exos was evaluated in vivo. After LXY30-Exos were isolated and identified, LXY30-Exos were confirmed to be internalized by NSCLC cells in vitro and specifically targeted NSCLC tumours in vivo. Functionally, LXY30-Exos-encapsulated miR-30c, miR-181b or miR-613 weakened the proliferation, migration and cell cycle of NSCLC cells induced cellular apoptosis in vitro and restrained the tumour progression in vivo. Meanwhile, the safety of LXY30-Exos-encapsulated miR-30c, miR-181b or miR-613 was confirmed in vivo. Overall, miR-30c, miR-181b and miR-613 encapsulated in LXY30 peptide-modified BMSC-Exos relieved NSCLC.

Nicotinamide improves the impaired extravillous trophoblast cell invasion induced by PM2.5 exposure-associated increase of TNFα secretion through the ROS/NF-κB/FLT1 pathway.

It has been well acknowledged that maternal exposure to fine particulate matters (PM2.5) might lead to poor pregnancy outcomes including the intrauterine growth restriction (IUGR) by interfering with the placental development. Our previous studies have demonstrated that maternal PM2.5 exposure induces IUGR, accompanied with increased maternal circulating TNFα level and impaired extravillous trophoblast cells (EVTs) invasion in mice. In this study, HTR8/SVneo cells, the immortalized human EVTs line, were used to assess effects and the underlying molecular mechanisms of nicotinamide on the impaired EVTs invasion. Our results showed that, the placental FLT1 protein level was significantly increased whereas maternal serum nicotinamide concentration was remarkably decreased in PM2.5-exposured pregnant mice at GD17.5 (vaginal plug day=GD0.5), compared to that in normal GD17.5 pregnant mice. FLT1 expression in HTR8/SVneo cells was significantly up-regulated by TNFα treatment, and the down-regulated FLT1 expression effectively abated the inhibitory effects of TNFα on HTR8/SVneo cells migration and invasion. Meanwhile, TNFα promoted reactive oxygen species (ROS) production and NF-κB signaling pathway activation in HTR8/SVneo cells in a dose-dependent manner. Nicotinamide treatment significantly reversed the effects of TNFα on cell migration and invasion, as well as the FLT1 expression, ROS production and NF-κB pathway activation. In summary, increased TNFα induced by PM2.5 exposure inhibits EVTs invasion by activating the ROS/NF-κB/FLT1 signaling pathway, and this adverse effect could be attenuated by nicotinamide treatment, suggesting a potential application in the clinical intervention of PM2.5-induced IUGR.

Unraveling the molecular landscape of breast muscle development in domestic Yuzhong pigeons and European meat pigeon: Insights from Iso-seq and RNA-seq analysis.

The mechanisms governing gene regulation in domestic Yuzhong pigeon breast muscle development remain largely elusive. Here, we conducted a comparative analysis using Iso-seq and RNA-seq data from domestic Yuzhong pigeons and European meat pigeons to uncover signaling pathways and genes involved in breast muscle development. The Iso-seq data from domestic Yuzhong pigeons yielded 131,377,075 subreads, resulting in 16,587 non-redundant high-quality full-length transcripts post-correction. Furthermore, utilizing pfam, CPC, PLEK, and CPAT, we predicted 5575, 4973, 2333, and 4336 lncRNAs, respectively. Notably, several genes potentially implicated in breast muscle development were identified, including tropomyosin beta chain, myosin regulatory light chain 2, and myosin binding protein C. KEGG enrichment analysis revealed critical signaling pathways in breast muscle development, spanning carbon metabolism, biosynthesis of amino acids, glycolysis/gluconeogenesis, estrogen signaling, PI3K-AKT signaling, protein processing in the endoplasmic reticulum, oxidative phosphorylation, pentose phosphate pathway, fructose and mannose metabolism, and tight junctions. These findings offer insights into the biological processes driving breast muscle development in domestic Yuzhong pigeon, contributing to our understanding of this complex phenomenon.

Heterologous expression of BACE1 and its interaction with Codonopsis pilosula polysaccharides and Lobetyolin.

BACE1, a crucial enzyme in the amyloid-ß deposition theory of Alzheimer's disease (AD), is targeted by Codonopsis pilosula, a traditional tonic believed to impede AD onset. However, the specific active compounds responsible for its effects remain elusive. Our prior network pharmacology research identified C. pilosula polysaccharides (CPPS) and Lobetyolin may serve as potential inhibitors of AD by suppressing amyloidogenesis. Here, we recombinantly expressed BACE1 under varied conditions and assessed its activity using Fluorescence Resonance Energy Transfer technology. Through spectroscopy, molecular docking, and dynamics, we elucidated the interactions of CPPS, Lobetyolin, and BACE1. Optimal BACE1 expression occurred at 22 °C with 0.4 mM IPTG for 6 h, yielding a 72 kDa protein. Enzyme kinetics displayed a maximum rate of 4096 µmol/min and a Michaelis constant of 16 mg/mL for BACE1. Spectroscopic analysis revealed differing binding affinities of the compounds at various temperatures, peaking at 293 K. Lobetyolin exhibited superior binding to BACE1 compared to CPPS, driven by hydrophobic and electrostatic forces. Molecular docking and dynamics highlighted hydrophobic amino acids' role in BACE1 interactions with Lobetyolin and CPPS, with binding energy < -1.2 kcal/mol signifying strong affinities. Notably, Lobetyolin and CPPS showed higher BACE1 affinity than APP, with the Lobetyolin-BACE1 complex being the most stable.

Intestinal health of squab pigeons responded to parental dietary protein levels during breeding period.

The objective of this study was to determine the effects of dietary crude protein (CP) levels on intestinal antioxidant status, tight junction proteins expression, and amino acids transporters levels in squabs. A total of 180 pairs of White King parent pigeons approximately 10 mo old were randomly assigned to 5 groups with 6 replications of 6 pairs of parental pigeons each, and were fed with 14, 15, 16, 17, and 18% CP diets for 46 d, respectively. Dietary increasing CP levels increased final body weight (linear and quadratic, P < 0.05), serum urea nitrogen (linear, P<0.05) and triglyceride levels (quadratic, P < 0.05), and reduced kidney relative weight (quadratic, P < 0.05) in squabs. Final body weight of squabs in the 18% CP diet group was higher than that of the 14, 15, and 16% CP diet groups (P < 0.05) but was similar to that of the 17% CP diet group (P > 0.05). Increasing dietary CP levels reduced intestinal malondialdehyde contents (linear and quadratic, P < 0.05) and jejunal total superoxide dismutase (T-SOD) activity (linear, P < 0.05), and enhanced (linear and quadratic, P<0.05) ileal catalase and T-SOD activities in squabs, and these effects were more prominent in the 17% CP diet group. Graded CP levels up-regulated the mRNA expression of intestinal zonula occludens 1 (linear, P < 0.05), solute carrier family 7 members 9 (linear, P < 0.05) and claudin 1 (CLDN1, linear and quadratic, P < 0.05), ileal CLDN3 and solute carrier family 6 members 14 (linear, P < 0.05) but lowered jejunal solute carrier family 6 member 14 (quadratic, P<0.05) mRNA expression in squabs. The effects of dietary CP levels on intestinal tight junction proteins expression were more apparent when its supplemental levels were 18%. These results suggested that increasing parental dietary CP levels ranged from 14 to 18% during breeding period improved growth and intestinal function of squabs, with its recommended level being 17%.

Diesel exhaust particulate matter induces GC-1 spg cells oxidative stress by KEAP1-NRF2 pathway and inhibition of ATP5α1 S-sulfhydration.

Diesel exhaust particle (DEP) exposure induces a variety of toxicological effects through oxidative stress and inflammation responses. This research investigated the mechanisms underlying DEP-induced GC-1spg cells oxidative stress by examining ROS accumulation, antioxidant defense systems activation, mitochondrial dysfunction, and the Nrf2/Keap1/HO-1 pathway response. Subsequently, we further evaluated the ATP levels, ATP5α synthase activity and ATP5α synthase S-sulfhydrated modification in DEP-exposed GC-1 spg cells. The results showed that DEP exposure significantly inhibited cell proliferation and viability, increased intracellular ROS production, decreased MMP, down-regulated antioxidant capacity, activated the Nrf2/Keap1/HO-1 pathway. However, DEP-induced oxidative stress was partially alleviated by GSH and exogenous H2S. In addition, DEP exposure induced ATP depletion and ATP5α synthase inactivity in GC-1 spg cells, accompanied by ATP5α synthase S-sulfhydrated modification. In conclusion, our research showed that DEP may incapacitate mitochondria through oxidative stress injury, leading to GC-1 spg cells oxidative stress. This process may be associated with the reduction of ATP5α1 S-sulfhydrated modification. It provides a new perspective for the research of the mechanism related to male reproductive toxicity due to air pollution.

A Whole-Process Visible Strategy for the Preparation of Rhizomucor miehei Lipase with Escherichia coli Secretion Expression System and the Immobilization.

BACKGROUND: Rhizomucor miehei (RM) lipase is a regioselective lipase widely used in food, pharmaceutical and biofuel industries. However, the high cost and low purity of the commercial RM lipase limit its industrial applications. Therefore, it is necessary to develop cost-effective strategies for large-scale preparation of this lipase. The present study explored the high-level expression of RM lipase using superfolder green fluorescent protein (sfGFP)-mediated Escherichia coli secretion system. RESULTS: The sfGFP(-15) mutant was fused to the C-terminus of RM lipase to mediate its secretion expression. The yield of the fusion protein reached approximately 5.1 g/L with high-density fermentation in 5-L fermentors. Unlike conventional secretion expression methods, only a small portion of the target protein was secreted into the cell culture while majority of the fusion protein was still remained in the cytoplasm. However, in contrast to intracellular expression, the target protein in the cytoplasm could be transported efficiently to the supernatant through a simple washing step with equal volume of phosphate saline (PBS), without causing cell disruption. Hence, the approach facilitated the downstream purification step of the recombinant RM lipase. Moreover, contamination or decline of the engineered strain and degradation or deactivation of the target enzyme can be detected efficiently because they exhibited bright green fluorescence. Next, the target protein was immobilized with anion-exchange and macropore resins. Diethylaminoethyl sepharose (DEAE), a weak-basic anion-exchange resin, exhibited the highest bind capacity but inhibited the activity of RM lipase dramatically. On the contrary, RM lipase fixed with macropore resin D101 demonstrated the highest specific activity. Although immobilization with D101 didn't improve the activity of the enzyme, the thermostability of the immobilized enzyme elevated significantly. The immobilized RM lipase retained approximately 90% of its activity after 3-h incubation at 80 °C. Therefore, D101 was chosen as the supporting material of the target protein. CONCLUSION: The present study established a highly efficient strategy for large-scale preparation of RM lipase. This innovative technique not only provides high-purity RM lipase at a low cost but also has great potential as a platform for the preparation of lipases in the future.

Degradation of petroleum hydrocarbon contaminants by Rhodococcus erythropolis KB1 synergistic with alfalfa (Medicago sativa L.).

Petroleum hydrocarbons are a stubborn pollutant that is difficult to degrade globally, and plant-microbial degradation is the main way to solve this type of pollutant. In this study, the physiological and ecological responses of alfalfa to petroleum hydrocarbons in different concentrations of petroleum hydrocarbon-contaminated soil with KB1 (Rhodococcus erythropolis) were analyzed and determined by laboratory potting techniques. The growth of alfalfa (CK) and alfalfa with KB1 (JZ) in different concentrations of petroleum hydrocarbons contaminated soil was compared and analyzed. The results of the CK group showed that petroleum hydrocarbons could significantly affect the activity of alfalfa antioxidant enzyme system, inhibit the development of alfalfa roots and the normal growth of plants, especially in the high-concentration group. KB1 strain had the ability to produce IAA, form biofilm, fix nitrogen, produce betaine and ACC deaminase, and the addition of KB1 could improve the growth traits of alfalfa in the soil contaminated with different concentrations of petroleum hydrocarbons, the content of soluble sugars in roots, and the stress resistance and antioxidant enzyme activities of alfalfa. In addition, the degradation kinetics of the strain showed that the degradation rate of petroleum could reach 75.2% after soaking with KB1. Furthermore, KB1 can efficiently degrade petroleum hydrocarbons in advance and significantly alleviate the damage of high concentration of petroleum hydrocarbons to plant roots. The results showed that KB1 strains and alfalfa plants could effectively enhance the degradation of petroleum hydrocarbons, which provided new ideas for improving bioremediation strategies.

Whole-Genome Sequencing for Identifying Candidate Genes Related to the Special Phenotypes of the Taihu Dianzi Pigeon.

The Taihu Dianzi pigeon is a breed native to China, and its special piebalding, crest, and polydactyly phenotypes are the result of artificial and natural selection. Here, we analyzed the genetic differences among three kinds of pigeons with different phenotypes at the genomic level. A selective sweep was conducted based on the fixation index (FST) and nucleotide diversity (π) ratio, and the results revealed that MC1R was related to the formation of the distinctive piebalding of the Taihu Dianzi pigeon. Combined with the results of genome-wide association studies, we identified candidate genes associated with the crest (SMYD and STOX2) and polydactyly (SLC52A3 and ANGPT4). The candidate genes identified in this study and their variants may be useful for understanding the genetic mechanism underlying the special phenotypes of the Taihu Dianzi pigeon. This study provides new insights into the genetic factors that may influence the formation of the special piebalding, crest, and polydactyly characteristics in pigeons.

Application scenario-oriented molecule generation platform developed for drug discovery.

Design of molecules for candidate compound selection is one of the central challenges in drug discovery due to the complexity of chemical space and requirement of multi-parameter optimization. Here we present an application scenario-oriented platform (ID4Idea) for molecule generation in different scenarios of drug discovery. This platform utilizes both library or rule based and generative based algorithms (VAE, RNN, GAN, etc.), in combination with various AI learning types (pre-training, transfer learning, reinforcement learning, active learning, etc.) and input representations (1D SMILES, 2D graph, 3D shape, binding site, pharmacophore, etc.), to enable customized solutions for a given molecular design scenario. Besides the usual generation followed screening protocol, goal-directed molecule generation can also be conducted towards predefined goals, enhancing the efficiency of hit identification, lead finding, and lead optimization. We demonstrate the effectiveness of ID4Idea platform through case studies, showcasing customized solutions for different design tasks using various input information, such as binding pockets, pharmacophores, and compound representations. In addition, remaining challenges are discussed to unlock the full potential of AI models in drug discovery and pave the way for the development of novel therapeutics.

Advances on the Role of Ferroptosis in Ionizing Radiation Response.

Ferroptosis is an iron-dependent programmed cell death mode that is distinct from other cell death modes, and radiation is able to stimulate cellular oxidative stress and induce the production of large amounts of reactive oxygen radicals, which in turn leads to the accumulation of lipid peroxide and the onset of ferroptosis. In this review, from the perspective of the role of ferroptosis in generating a radiation response following cellular irradiation, the relationship between ferroptosis induced by ionizing radiation stress and the response to ionizing radiation is reviewed, including the roles of MAPK and Nrf2 signaling pathways in ferroptosis, resulting from the oxidative stress response to ionizing radiation, the metabolic regulatory role of the p53 gene in ferroptosis, and regulatory modes of action of iron metabolism and iron metabolism-related regulatory proteins in promoting and inhibiting ferroptosis. It provides some ideas for the follow-up research to explore the specific mechanism and regulatory network of ferroptosis in response to ionizing radiation.

Development and Comprehensive Benchmark of a High-Quality AMBER-Consistent Small Molecule Force Field with Broad Chemical Space Coverage for Molecular Modeling and Free Energy Calculation.

Biomolecular simulations have become an essential tool in contemporary drug discovery, and molecular mechanics force fields (FFs) constitute its cornerstone. Developing a high quality and broad coverage general FF is a significant undertaking that requires substantial expert knowledge and computing resources, which is beyond the scope of general practitioners. Existing FFs originate from only a limited number of groups and organizations, and they either suffer from limited numbers of training sets, lower than desired quality because of oversimplified representations, or are costly for the molecular modeling community to access. To address these issues, in this work, we developed an AMBER-consistent small molecule FF with extensive chemical space coverage, and we provide Open Access parameters for the entire modeling community. To validate our FF, we carried out benchmarks of quantum mechanics (QM)/molecular mechanics conformer comparison and free energy perturbation calculations on several benchmark data sets. Our FF achieves a higher level of performance at reproducing QM energies and geometries than two popular open-source FFs, OpenFF2 and GAFF2. In relative binding free energy calculations for 31 protein-ligand data sets, comprising 1079 pairs of ligands, the new FF achieves an overall root-mean-square error of 1.19 kcal/mol for ΔΔG and 0.92 kcal/mol for ΔG on a subset of 463 ligands without bespoke fitting to the data sets. The results are on par with those of the leading commercial series of OPLS FFs.

Methane hydrate phase equilibrium considering dissolved methane concentrations and interfacial geometries from molecular simulations.

Natural gas hydrates, mainly existing in permafrost and on the seabed, are expected to be a new energy source with great potential. The exploitation technology of natural gas hydrates is one of the main focuses of hydrate-related studies. In this study, a large-size liquid aqueous solution wrapping a methane hydrate system was established and molecular dynamics simulations were used to investigate the phase equilibrium conditions of methane hydrate at different methane concentrations and interfacial geometries. It is found that the methane concentration of a solution significantly affects the phase equilibrium of methane hydrates. Different methane concentrations at the same temperature and pressure can lead to hydrate formation or decomposition. At the same temperature and pressure, in a system reaching equilibrium, the size of spherical hydrate clusters is coupled to the solution concentration, which is proportional to the Laplace pressure at the solid-liquid interface. Lower solution concentrations reduce the phase equilibrium temperature of methane hydrates at the same pressure; as the concentration increases, the phase equilibrium temperature gradually approaches the actual phase equilibrium temperature. In addition, the interfacial geometry of hydrates affects the thermodynamic stability of hydrates. The spherical hydrate particles have the highest stability for the same volume. Through this study, we provide a stronger foundation to understand the principles driving hydrate formation/dissociation relevant to the exploitation of methane hydrates.

Facilitation of Hydrate Dissociation and Structural Evolution by Major Marine Anions under Static Electric Fields.

Electric fields have been proven to be capable of significantly affecting the equilibrium state of hydrates. In this study, the thermodynamic properties and structural changes of methane hydrate (MH) in various anion solutions in an electric field at 0.7 V/nm were investigated by molecular dynamics simulations. The presence of anions significantly enhances the instability of methane hydrates under electric fields, leading to a staged dissociation process. First, the anions coexist with MH to form a temporary metastable structure under the action of an electric field. Then, the migration of anions causes the dissociation of nearby hydrates and the formation of flow channels in the hydrate layer, which leads to the complete dissociation of MH after a period. The promotive effects of F-, Br-, I-, and Cl- ions were close, while SO42- was relatively weak. The anions are still in hydration shells in the MH phase, but the structure of the hydration shells differs slightly from that in solution (the coordination numbers of I- and SO42- ions increased). The migration resistances of multiple anions to cross the surface of the hydrate layer are similar. However, inside the hydrate phase, the anions with a larger radius have a higher migration resistance. It is difficult for SO42- ions to migrate inside the hydrate phase, and they tend to form a metastable structure on the hydrate surface. Combining our previous studies, SrCl2 solution has the best hydrate promotion under an electric field environment.

DDX52 gene expression in LUAD tissues indicates potential as a prognostic biomarker and therapeutic target.

Lung adenocarcinoma (LUAD) remains a leading cause of cancer-related morbidity and mortality globally. While DDX52, an ATP-dependent RNA helicase, plays a role in several biological processes, its specific involvement in LUAD is yet to be elucidated. We utilized ROC curves to determine DDX52's predictive potential for LUAD. Kaplan-Meier survival curves, along with univariate and multivariate Cox analyses, assessed the prognostic implications of DDX52 in LUAD. We constructed nomogram models to further delineate DDX52's influence on prognosis, employed GSEA for functional analysis, and used qRT-PCR to examine DDX52 expression in LUAD tissues. DDX52 expression was notably higher in LUAD tissues, suggesting its potential as a negative prognostic marker. We observed a direct relationship between DDX52 expression and advanced T and N stages, as well as higher grading and staging in LUAD patients. Cox analyses further underscored DDX52's role as an independent prognostic determinant for LUAD. GSEA insights indicated DDX52's influence on LUAD progression via multiple signaling pathways. Our nomogram, founded on DDX52 expression, effectively projected LUAD patient survival, as validated by calibration curves. Elevated DDX52 expression in LUAD tissues signals its potential as a poor prognostic marker. Our findings emphasize DDX52's role not only as an independent prognostic factor for LUAD but also as a significant influencer in its progression through diverse signaling pathways. The constructed nomogram also underscores the feasibility of predicting LUAD patient survival based on DDX52 expression.

Genomic Characteristics and Comparative Genomics Analysis of the Endophytic Fungus Paraphoma chrysanthemicola DS-84 Isolated from Codonopsis pilosula Root.

Paraphoma chrysanthemicola is a newly identified endophytic fungus. The focus of most studies on P. chrysanthemicola has been on its isolation, identification and effects on plants. However, the limited genomic information is a barrier to further research. Therefore, in addition to studying the morphological and physiological characteristics of P. chrysanthemicola, we sequenced its genome and compared it with that of Paraphoma sp. The results showed that sucrose, peptone and calcium phosphate were suitable sources of carbon, nitrogen and phosphorus for this strain. The activities of amylase, cellulase, chitosanase, lipase and alkaline protease were also detected. Sequencing analysis revealed that the genome of P. chrysanthemicola was 44.1 Mb, with a scaffold N50 of 36.1 Mb and 37,077 protein-coding genes. Gene Ontology (GO) annotation showed that mannose-modified glycosylation was predominant in monosaccharide utilisation. The percentage of glycoside hydrolase (GH) modules was the highest in the carbohydrate-active enzymes database (CAZy) analysis. Secondary metabolite-associated gene cluster analysis identified melanin, dimethylcoprogen and phyllostictine A biosynthetic gene clusters (>60% similarity). The results indicated that P. chrysanthemicola had a mannose preference in monosaccharide utilisation and that melanin, dimethylcoprogen and phyllostictine A were important secondary metabolites for P. chrysanthemicola as an endophytic fungus.

Hsa-miR-223-3p participates in the process of anthracycline-induced cardiomyocyte damage by regulating NFIA gene.

Irreversible cardiomyopathy was caused by the therapeutic of anthracyclines in the chemotherapy of cancers. The cell apoptosis and autophagy were induced by anthracyclines in AC16 cells. MiR-223-3p ascends in anthracycline-treated AC16, but the expression of nuclear factor I-A (NFIA) was specifically down-regulated. However, the underlying molecular mechanism between NFIA and miR-223-3p is unclear now in AC16 cells. In our research, NFIA expression was dampened in AC16 cells by miR-223-3p mimics. Additionally, miR-223-3p knockdown hindered the apoptosis and autophagy in anthracycline-treated AC16. Furthermore, NFIA was predicted and verified as a miR-223-3p's downstream target and rescued the functions of miR-223-3p. These findings illustrated that miR-223-3p advances anthracycline-stimulated cardiomyocyte damage progression by targeting NFIA, implying the promising therapeutic function of miR-223-3p on cardiomyocyte damage in cancer patients.

Hit Identification Driven by Combining Artificial Intelligence and Computational Chemistry Methods: A PI5P4K-ß Case Study.

Computer-aided drug design (CADD), especially artificial intelligence-driven drug design (AIDD), is increasingly used in drug discovery. In this paper, a novel and efficient workflow for hit identification was developed within the ID4Inno drug discovery platform, featuring innovative artificial intelligence, high-accuracy computational chemistry, and high-performance cloud computing. The workflow was validated by discovering a few potent hit compounds (best IC50 is ∼0.80 µM) against PI5P4K-ß, a novel anti-cancer target. Furthermore, by applying the tools implemented in ID4Inno, we managed to optimize these hit compounds and finally obtained five hit series with different scaffolds, all of which showed high activity against PI5P4K-ß. These results demonstrate the effectiveness of ID4inno in driving hit identification based on artificial intelligence, computational chemistry, and cloud computing.

Antitumor activity of a whey peptide-based enteral diet in C26 colon tumor-bearing mice.

The antitumor effects of a whey peptide-based enteral diet, whose main components are whey peptides and yogurt fermented by Lactobacillus delbureckii subsp. bulgaricus 2038 and Streptococcus thermophilus 1131, were investigated in mice. Our results indicated that the tumor weight in C26 carcinoma-transplanted mice was significantly smaller at day 16 post-implantation in the whey peptide-based enteral diet group (1.36 ± 0.54 g) than in the control group (1.83 ± 0.89 g) (p < 0.05). The whey peptide-based enteral diet group exhibited higher tumor cell apoptosis, lower cell proliferation, and inactive angiogenesis indicating by higher degree of TUNEL, lower positive rates of Ki-67, VEGF, and CD34 than control group. It also attenuated inflammatory cell infiltration of spleen and liver as indicated by the decreased spleen index (10.89 ± 2.06 vs. 12.85 ± 2.92, p < 0.05) and increased liver index (58.09 ± 11.37 vs. 53.19 ± 6.67, p < 0.05) in the whey peptide-based enteral diet group than the control diet group. These results proved the inhibitory effect of the whey peptide-based enteral diet on tumor growth, which might be attributed to the whey peptides component. PRACTICAL APPLICATION: A whey peptide-based enteral diet (MEIN® ), containing cheese whey and multiple nutrients, was selected to verify the anti-tumor effect by animal experiments. The tumor weight growth, tumor cell proliferation, inflammatory cell infiltration of spleen and liver in tumor model mice was significantly attenuated by the whey peptide-based enteral diet, that might be attributed to its whey peptides component. These results provided an additive direction for cancer therapy and need a further study including clinical trials.

Effects of Rapid Quenching on Grain Boundary Microstructure and Mechanical Properties of an Al-Mg-Si-Cu Alloy.

Precipitate free zones (PFZs) near grain boundaries generally soften alloys. The quenching rate after solution treatment is an important factor influencing the width of PFZs in Al-Mg-Si-Cu alloy. This study explored the effects of high quenching rates on the grain boundary microstructures and mechanical properties of an Al-Mg-Si-Cu alloy. Samples of various thickness were quenched in water at room temperature and in ethylene glycol at -40 °C, respectively. The results showed that the rapidly quenched samples at -40 °C exhibited better comprehensive mechanical properties than the water-quenched samples. Transmission electron microscopy studies revealed the rapidly quenched samples had wider PFZs, shorter intragranular precipitates, and larger grain boundary precipitates (GBPs) than water-quenched samples. It is proposed that when the quenching rate exceeds the critical cooling rate, e.g., in water quenching or rapid quenching, the formation of PFZs is controlled by the solute depletion mechanism rather than the vacancy depletion mechanism. The nucleation and growth of GBPs thus lead to the depletion of solute atoms, resulting in wider PFZs rather than thinner PFZs according to previous knowledge. This research provides valuable insights into the application of rapid quenching technology for modifying alloys' microstructures and properties.