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There is an urgent need to develop low-cost， high-strength， and toughness grades of steel for domestic wind power fasteners in order to enhance the competitiveness of the industrial chain and fully participate in market competition. Through the control of smelting process to assure residual w ［P］≤0.015% and w［S］≤ 0.010% and the total oxygen content w［T.O］ stably controlled to be less than 10 × 10-6 during low oxygen operation practice. Two stage low-temperature rolling is adopted and the single pass reduction rate is controlled between 8% to 12%. A 10.9-grade 32CrB4 bolt steel with good impact toughness at -40 ℃ low-temperature for 38.8 mm specification has been successfully developed. The results of mechanical property inspection and metallographic observation indicate that the developed steel has good tensile properties and excellent low-temperature impact properties. The optimal heat treatment process has been studied， which is 820 ℃ soaking water quenching and 510 ℃ soaking tempering. The room temperature tensile strength can reach 1 075 MPa， and the average low-temperature impact value of -40 ℃ KV2 can be 53 J. The microstructure is mainly tempered martensite， with excellent and comprehensive mechanical properties and good uniformity.

Aims This study evaluates the antibacterial characteristics and mechanisms of combined tea polyphenols (TPs), Nisin, and ε-polylysine (PL) against Streptococcus canis, Streptococcus minor, Streptococcus mutans , and Actinomyces oris , common zoonotic pathogens in companion animals. Methods and results Pathogenic strains were isolated from feline oral cavities and assessed using minimum inhibitory concentration (MIC) tests, inhibition zone assays, growth kinetics, and biofilm inhibition studies. Among single agents, PL exhibited the lowest MIC values against all four pathogens. TP showed significant resistance against S. minor , and Nisin against S. mutans. The combination treatment (Comb) of TP, Nisin, and PL in a ratio of 13:5:1 demonstrated broad-spectrum antibacterial activity, maintaining low MIC values, forming large inhibition zones, prolonging the bacterial lag phase, reducing growth rates, and inhibiting biofilm formation. RNA sequencing and metabolomic analysis indicated that TP, Nisin, and PL inhibited various membrane-bound carbohydrate-specific transferases through the phosphoenolpyruvate-dependent phosphotransferase system in S. canis , disrupting carbohydrate uptake. They also downregulated glycolysis and the citric acid cycle, inhibiting cellular energy metabolism. Additionally, they modulated the activities of peptidoglycan glycosyltransferases and d -alanyl- d -alanine carboxypeptidase, interfering with peptidoglycan cross-linking and bacterial cell wall stability. Conclusions The Comb therapy significantly enhances antibacterial efficacy by targeting multiple bacterial pathways, offering potential applications in food and pharmaceutical antimicrobials. [ABSTRACT FROM AUTHOR]

To construct the microemulsion delivery system (ME) loading ATSO and NA and study their physicochemical characteristics to enhance their stability and water solubility. By plotting ternary phase diagrams, the composition and proportions of the MEs were determined. The physicochemical characteristics and stability of MEs were evaluated by mean diameter, polydispersity index (PDI), pH, electrical conductivity, transmission electron microscopy (TEM), rheological behaviour measurement, and phase inversion temperature (PIT). The MEs was composed with EL-40 as a surfactant and specifically with the addition of ethanol as a cosurfactant in NA-loaded ME. The mean diameters of ATSO-loaded ME and NA-loaded ME were 39.65 ± 0.24 nm and 32.90 ± 2.65 nm, and PDI were 0.49 ± 0.01 and 0.28 ± 0.14, respectively. The TEM confirmed the spherical and smooth morphology of MEs. The rheological results indicated that MEs are dilatant fluids with the advantages of low viscosity, high fluidity, and tolerance to temperature fluctuations. The mean diameter and PDI of MEs showed no significant change after storage at 25 °C for 28 days and centrifugation. The prepared microemulsions could expand the application prospects of ATSO and NA products in cosmetics, medicine, foods and other fields. [ABSTRACT FROM AUTHOR]

BACKGROUND: Calcium is important in the formation of bones and teeth, cell metabolism, and other physiological activities. In this work, casein phosphopeptide‐calcium chelate (CPP‐Ca) was synthesized and the optimal process parameters for the chelation reaction were obtained. The bioavailability of calcium in CPP‐Ca was investigated by in vitro gastrointestinal simulated digestion. The existence of phytic acid and oxalic acid in the digestion system was evaluated to clarify the calcium holding ability of casein phosphopeptide (CPP). Liquid chromatography–tandem mass spectrometry (LC‐MS/MS) was used to identify oligopeptides from CPP‐Ca. RESULTS: The optimal process parameters for the chelation reaction were: peptide concentration 7.76 mgmL−1, pH 8.54, and reaction temperature 43.3 °C. The digestion in vitro results indicated that the calcium release rate of CPP‐Ca in the stomach for 2 h reached 85%, and about 50% of the ionized calcium was re‐chelated with CPP in the intestine. Phytic acid and oxalic acid could lead to a sharp decrease in soluble calcium but around 50% of the calcium was still retained in the form of chelates in the presence of CPP. The LC‐MS/MS identified 19 casein‐derived oligopeptides after digestion, and calcium modifications were found on eight peptides derived from β‐casein and αs2‐casein. CONCLUSIONS: This study clarified the excellent calcium holding capacity of CPP in the presence of phytic acid and oxalic acid. Liquid chromatography–tandem mass spectrometry also revealed peptide changes, and identified peptides that chelate with calcium. These findings provided significant insights that could be relevant to the further utilization and product development of peptide‐calcium chelate in the food industry. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Ethnopharmacological Relevance: Stone symptoms are one of the most common health problems in pets. Inflammation in the kidneys causes the pet's urine to form a hard substance that blocks the urinary tract. Plantago asiatica L. and Lonicera japonica Thunb., as traditional Chinese diuretics, have remarkable effects on anti-inflammatory and analgesia. However, their mechanism of action remains unclear., Purpose: The alleviating effect of Plantago asiatica and Lonicera japonica extracts upon lipopolysaccharide (LPS)-induced inflammation in canine and feline kidney cells was investigated in this work., Materials and Methods: Inflammatory factor concentrations and oxidative stress indicators were used to evaluate the inflammatory response. The mechanism by which two extracts reduced inflammation was explored using quantitative real-time polymerase chain reaction (RT-qPCR) and high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) metabolome assay., Results: The results demonstrated that Plantago asiatica or Lonicera japonica extract at safe concentration (25-200 μg/mL for canine kidney cell and 1-20 μg/mL for feline kidney cell, respectively) could significantly reduce the release of nitric oxide (p < 0.05) and oxidative damage (p < 0.05) after LPS stimulation, inhibit the production of inflammatory factors (p < 0.05), and improve cell migration ability (p < 0.05). The RT-qPCR results confirmed that Plantago asiatica and Lonicera japonica extracts significantly reduced the mRNA expressions of TLR4, MyD88, NF-kB, Caspase9 and Bax (p < 0.05), and enhanced the mRNA expression of Bcl-2 (p < 0.05). Non-targeted metabolomics results indicated that the cells treated with two extracts raised the contents of allopurinol, further inhibited uric acid and gout and lowered the contents of adenosine and adenine. Moreover, it was revealed that the Plantago asiatica and Lonicera japonica participated in purine metabolism, glycerophospholipid metabolism, protein digestion and absorption, nucleotide metabolism pathways to alleviate kidney cell inflammation., Conclusions: The interaction mechanism was revealed to reduce the content of inflammatory factors by inhibiting TLR4-MyD88-NF-kB signaling pathway, and participate in purine metabolism to reduce the inflammation of kidney cells. These findings could provide significant insight into alleviating nephritis in canine and feline, and strategies for preventing urinary tract and kidney stones using Plantago asiatica and Lonicera japonica extracts., Competing Interests: Declaration of competing interest I have nothing to declare., (Copyright © 2024 Elsevier B.V. All rights reserved.)