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Aconitine hydrolysis is deemed to be the guarantee for the safe application of Aconitum phytomedicine. Studies have suggested that hydrolysates of aconitine not only include benzoylaconitine and aconine, but other hydrolysates. Moreover, these hydrolysates maybe have a mutual transformation relationship, which has not been confirmed. Herein, hydrolysates of aconitine and their mutual transformation relationship were studied by the theoretical quantum chemistry, UPLC-Q-TOF-MS, the separation and identification of target products, etc. Then the toxicity of its hydrolysates was evaluated. The results demonstrate that the probability is the same for aconitine hydrolysis to pyroaconitine and benzoylaconitine, but they are difficult to convert to each other. Aconitine hydrolysis has three independent hydrolysis pathways, 1) to indaconitine, 2) to benzoylaconitine, and aconine, 3) to pyroaconitine and to 16-epi-pyroaconine. The result of embryotoxicity evaluation on zebrafish was aconitine > indaconitine > benzoylaconitine > α-pyroaconitine > β- pyroaconitine > aconine > 16-epi-pyroaconine. In conclusion, aconitine have three independent hydrolysis pathways and the hydrolysates of different pathways cannot be transformed into each other. Pyroaconitine is a hydrolysate of aconitine except for benzoylaconitine, and its toxicity is lower than benzoylaconitine. More importantly, it clarifies the long-standing debate and provides scientific evidence for the processing and detoxification of Aconitum phytomedicine.

Semi-hydrogenation of acetylene is of great importance for both industry and academia. High prices and limited supplements of noble metals leave room for developing base metal catalysts. Experiments revealed the atomically dispersed Cu supported by Al2O3 with excellent long-term stability and high ethylene selectivity, but the physical nature has rarely been investigated theoretically. DFT calculations and microkinetic modeling revealed that the surface OH species could stabilize Cu1/Al2−δO3 and enhance its catalytic performance. The selectivity of ethylene formation decreases with increasing copper clusters (e.g., Cu1/Al2−δO3> Cu4/Al2−δO3> Cu8/Al2−δO3), meaning that the atomically dispersed copper may be a potential candidate for acetylene semi-hydrogenation. The structures of a series of single site catalysts M1/Al2−δO3 (M = Fe, Co, Ni, Ag, Au) are similar to that of Cu1/Al2−δO3, but their performances in catalyzing acetylene semi-hydrogenation are different. M1/Al2−δO3 (M = Ag, Au) shows higher selectivity than Cu1/Al2−δO3, while M1/Al2−δO3 (M = Fe, Co, Ni) demonstrates a higher turnover frequency (TOF) of ethylene than Cu1/Al2−δO3. Moreover, our results indicate that the Ni1–Cu1/Al2−δO3 alloy shows both high activity and ethylene selectivity. The present results show a compensation between the reactivity and the selectivity, suggesting that alloys of VIIIB metals with IB metals like Ni1–Cu1/Al2−δO3 may be efficient candidate catalysts in acetylene selective hydrogenation. [ABSTRACT FROM AUTHOR]

The experiment was to investigate the effect of dietary cysteine supplementation on reproductive performance of sows, antioxidant capacity and intestinal microflora of piglets. A total of 120 sows at the late gestation (100-114) d were randomly divided into three groups, with five replicates in each group and eight sows in each replicate. Sows in three groups were fed with diets supplemented with 0, 1.5 and 3 g/kg cysteine, respectively, from gestation low 100 d to weaning day. The results showed that litter number, litter birth weight and litter weaning weight of sows in 3 g/kg cysteine group were significantly lower than those in control group and 1.5 g/kg cysteine group (P<0.05), and live litter number in 1.5 g/kg cysteine group was significantly higher than that in 3 g/kg cysteine group (P<0.05). Compared with control group, the serum superoxide dismutase activity of piglets in 1.5 and 3 g/kg cysteine group was significantly increased by 30.97% and 27.1.3% (P<0.05), respectively, but the malondialdehyde concentration of piglets was significantly decreased by 61.90% and 71.43% (P<0.05). Compared with control group, the serum malondialdehyde concentration of piglets in 1.5 and 3 g/kg cysteine groups on weaning day was significantly decreased by 63.79% and 70.69% (P<0.05), respectively. The number of posterior wall bacteria in ileum of of piglets in control group was significantly higher than that of 3 g/kg cysteine group (P<0.05), while the number of Proteus and Clostridium were significantly lower than that of 3 g/kg cysteine group (P<0.05). The number of Bacteroides coli in 1.5 and 3 g/kg cysteine groups was significantly higher than that in control group (P<0.05). The experiment indicates that sows fed with 3 g/kg cysteine diet during late gestation and lactation can reduce litter size and litter weight at weaning, while supplementation with 1.5 to 3 g/kg cysteine can significantly improve antioxidant performance at birth and weaning. [ABSTRACT FROM AUTHOR]

A rapid, simple, inexpensive fluorescence analysis method for determination of famotidine based on polyethyleneimine (PEI)‐capped Ag nanoclusters (PEI‐Ag NCs) was developed. The study showed that addition of famotidine could cause efficient quenching of PEI‐Ag NC fluorescence, as the presence of famotidine could cause aggregation of Ag NCs and quench its fluorescence. The sensitivity and selectivity of the method were investigated and experimental conditions such as buffer type, pH, temperature, and reaction time were optimized. Under optimized conditions, the results showed a linear profile from 3.7 × 10−8 to 3.7 × 10−5 mol/L, and had a detection limit of 1.6 × 10−9 mol/L (S/N = 3). [ABSTRACT FROM AUTHOR]

Maspin is a serine protease inhibitor that is encoded by the human SERPINB5 gene. As a tumor inhibitor, it can inhibit the growth of tumor cells, increase adhesion between tumor cells and inhibit tumor angiogenesis. In the present study, a meta- and bioinformatics analysis was performed through the PubMed and China National Knowledge Infrastructure databases including entries added until up to March 20, 2023. It was found that compared with normal breast tissue, maspin expression was downregulated in breast cancer tissue. Maspin expression was negatively associated with lymph node metastasis. According to Kaplan-Meier plotter, it was found that lower maspin expression was negatively associated with the overall and distant metastasis-free survival rate of patients with estrogen receptor-positive, luminal A and grade 2 breast cancer. High expression of maspin was also positively associated with the relapse-free survival rate of patients of the luminal A subtype. Low maspin expression was positively associated with the post-progression and distant metastasis-free survival rate of the progesterone receptor-negative subtype. According to the GEPIA database, SERPINB5 mRNA expression was higher in normal than breast cancer tissues and negatively correlated with the TNM stage. High expression of maspin was also positively associated with the overall survival rate. In the UALCAN database, it was found that the mRNA and promoter methylation levels of SERPINB5 were higher in normal than in breast cancer tissues. These findings suggest that the expression of maspin may serve as a potential marker to indicate the occurrence, subsequent progression and even prognosis of breast cancer. [ABSTRACT FROM AUTHOR]