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The primer coating technology applicable to a variety of aluminum alloys and steel materials has become a key requirement for the manufacturing of lightweight body for new energy vehicles. In this paper, a study on chemical conversion of metal surfaces based on the titanium/zirconium composite system was carried out on 6061 and 7075 aluminum alloys and galvanized steel. The effects of H2TiF6 concentration, H2ZrF6 concentration and process parameters on the corrosion resistance of the coatings formed on the surfaces of the three metals were investigated through copper sulfate spot experiments, and the corrosion resistance of the coatings was verified by electrochemical testing. Moreover, the scanning electron microscope and the energy spectrometer were employed to observe and analyze the surface morphology and element composition of the conversion coatings. Results showed that after a conversion treatment under the conditions that the H2TiF6 concentration was 1.60～2.00 mL/L, the H2ZrF6 concentration was 0.80～1.30 mL/L, the conversion time was 90 ～ 150 s, the pH value was 3.5 ～ 4.5, and the temperature was 30～40 ℃, these three kinds of metal materials possessed good corrosion resistance. The Jcorr of three metal materials decreased significantly in comparison with that of the blank sample, and the Ecorr of the blank sample was significantly lower than that of the other samples. In addition, the EIS spectrum showed that the film resistance Rct of the three metal materials treated with chemical conversion was significantly higher than that of the blank sample. The differences in the surface microstructure of the samples at different times was observed by SEM, and there were significantly fewer micropores and cracks on the surfaces of 6061 and 7075 aluminum alloys and galvanized steel after a treatment for 120 s.

BACKGROUND: Xanthomonas oryzae pv. oryzae (Xoo) is often considered one of the most destructive bacterial pathogens causing bacterial leaf blight (BLB), resulting in significant yield and cost losses in rice. In this study, a series of novel derivatives containing the isopropanolamine moiety linked to various substituted phenols and piperazines were designed, synthesized and screened. RESULTS: Antibacterial activity results showed that most compounds had good inhibitory effects on Xoo, among which compound W2 (EC50 = 2.74 μg mL−1) exhibited the most excellent inhibitory activity, and W2 also had a certain curative effect (35.89%) on rice compared to thiodiazole copper (TC) (21.57%). Scanning electron microscopy (SEM) results indicated that compound W2 could cause rupture of the Xoo cell membrane. Subsequently, proteomics and quantitative real‐time polymerase chain reaction revealed that compound W2 affected the physiological processes of Xoo and may exert antibacterial activity by targeting the two‐component system pathway. Interestingly, W2 upregulated Xoo's methyltransferase to impact on its pathogenicity. CONCLUSION: The present study offers a promising phenolic‐piperazine‐sopropanolamine compound as an innovative antibacterial strategy by specifically targeting the two‐component system pathway and inducing upregulation of methyltransferase to effectively impact Xoo's pathogenicity. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Plant bacterial infections and plant viruses seriously affect the yield and quality of crops. Based on the various activities of tryptanthrin, a series of tryptanthrin analogues bearing F and piperazine moieties were designed, synthesized, and evaluated for their biological activities against three plant bacteria and tobacco mosaic virus (TMV). RESULTS: Bioassay results indicated that compounds 6a–6l displayed excellent antibacterial activities in vitro and 6a–6c and 6g exhibited better antiviral activities against TMV than commercial ribavirin. In particular, 6b showed the most effect on Xanthomonas oryzae pv. oryzae (Xoo) with a half‐maximal effective concentration (EC50) of 1.26 μg mL−1, compared with the commercial pesticide bismerthiazol (BT; EC50 = 34.3 μg mL−1) and thiodiazole copper (TC; EC50 = 73.3 μg mL−1). Meanwhile, 6a also had the best antiviral activity at 500 μg mL−1 for curative, protection, and inactivation purposes, compared with ribavirin in vivo. CONCLUSION: Compound 6b could cause changes in bacterial morphology, induce the accumulation of reactive oxygen species, promote apoptosis of bacterial cells, inhibit the formation of biofilm, and block the growth of Xoo cells. Proteomic analysis revealed major differences in the bacterial secretory system pathways T2SS and T6SS, which inhibited membrane transport. Molecular docking revealed that 6a and 6g could interact with TMV coat protein preventing virus assembly. These results suggest that tryptanthrin analogues bearing F and piperazine moieties could be promising candidate agents for antibacterial and antiviral use in agricultural production. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The resistance of silkworms to Bombyx mori nuclear polyhedrosis virus (BmNPV) is controlled by a major dominant gene and multiple modifying genes. Given the presence of modified genes, it is difficult to determine the main gene by positional cloning. In this study, the main anti-BmNPV gene of BmNPV-resistant silkworm variety N was introduced into the susceptible variety Su to breed the near-isogenic line SuN with BmNPV resistance. The infection process of BmNPV in the hemolymph of Su and SuN was analyzed using the cell analysis system TissueFAXS PLUS. According to the law of infection and proliferation, hemolymph was extracted every 6 h for two-dimensional electrophoresis (2-DE) analysis and quantitative real-time polymerase chain reaction (qRT-PCR). Seven DEPs were found in comparisons between Su and SuN by 2-DE analysis. Among them, acid phosphatase, storage protein, and phenoloxidase can prevent pathogen invasion, which may play a role against BmNPV. Polyamine oxidase plays an important role in energy metabolism, which may be indirectly involved in the process of resisting BmNPV. Most of the transcriptional expression profiles of the seven DEPs were consistent with the 2-DE results. This study can provide a reference for the identification of anti-BmNPV genes and the breeding of BmNPV-resistant silkworm varieties. [ABSTRACT FROM AUTHOR]

Trehalose is a non-reducing disaccharide and participates in physiological activities such as organ formation, energy metabolism, and stress resistance in insects. The Bmtret1 gene family is mainly involved in in the sugar metabolism of silkworm. In the present study, phylogenetic analysis divided 21 Bmtret1 orthologs into three clades. These genes are equally distributed on the nine chromosomes. The cis-elements in the promoter regions of Bmtret1s indicated the possible function of Bmtret1s in response to hormones and environmental stimulus. The qPCR analysis showed the significantly different expression levels of Bmtret1s in different tissues and organs, indicating possible functional divergence. In addition, most Bmtret1s showed disturbed expression levels in response to silkworm nuclear polyhedrosis virus (BmNPV) stresses. Our results provide a clue for further functional dissection of the Tret1s in Bombyx mori and implicate them as potential regulators of antiviral responses. [ABSTRACT FROM AUTHOR]

Most randomized trials for acute promyelocytic leukemia (APL) have investigated highly selected patients under idealized conditions, and the findings need to be validated in the real world. We conducted a population-based study of all APL patients in Zhejiang Province, China, with a total population of 82 million people, to assess the generalization of all-trans retinoic acid (ATRA) and arsenic as front-line treatment. The outcomes of APL patients were also analyzed. Between January 2015 and December 2019, 1,233 eligible patients were included in the final analysis. The rate of ATRA and arsenic as front-line treatment increased steadily from 66.2% in 2015 to 83.3% in 2019, with no difference among the size of the center (≥5 or <5 patients per year, p = 0.12) or age (≥60 or <60 years, p = 0.35). The early death (ED) rate, defined as death within 30 days after diagnosis, was 8.2%, and the 3-year overall survival (OS) was 87.9% in the whole patient population. Age (≥60 years) and white blood cell count (>10 × 109/L) were independent risk factors for ED and OS in the multivariate analysis. This population-based study showed that ATRA and arsenic as front-line treatment are widely used under real-world conditions and yield a low ED rate and a high survival rate, which mimic the results from clinical trials, thereby supporting the wider application of APL guidelines in the future. [ABSTRACT FROM AUTHOR]