ObjectiveTo explore the mechanism by which Yizhi Qingxin prescription improves mitochondrial dysfunction in Alzheimer's disease （AD） through regulating mitochondrial Ca²⁺ homeostasis and kinetic balance based on the protein kinase A （PKA）/calcineurin （CaN） signaling pathway. MethodsSixty three-month-old amyloid precursor protein （APP）/presenilin 1 （PS1） double transgenic mice were randomly divided into a model group， a donepezil group（0.65 mg·kg^-1）， a low-dose Yizhi Qingxin prescription group （YQF-L，2.6 g·kg^-1）， a medium-dose Yizhi Qingxin prescription group （YQF-M，5.2 g·kg^-1）， and a high-dose Yizhi Qingxin prescription group （YQF-H，10.4 g·kg^-1）， with 12 mice in each group. Twelve C57BL/6J mice with the same genetic background served as a normal group. Each treatment group received gavage administration daily， with the model and normal groups receiving equal volume of physiological saline. Intervention continued for 12 consecutive weeks. The learning and memory abilities of the mice were assessed using the novel object recognition （NOR） and Morris water maze （MWM） tests. Hematoxylin-eosin （HE）/Nissl staining was used to observe histopathological changes in the hippocampus. Transmission electron microscopy （TEM） was used to observe mitochondrial ultrastructure. Fluo-4 acetoxymethyl ester （Fluo-4 AM） Ca²⁺ probe was used to measure intracellular Ca²⁺ concentration in brain tissue. Western blot was used to determine the protein expression of PKA， CaN， sodium/calcium/lithium exchanger （NCLX）， mitochondrial calcium uniporter （MCU）， calmodulin （CaM）， dynamin-related protein 1 （Drp1）， and phosphorylated dynamin-related protein 1 （serine 637 site） ［p-Drp1（S637）］ in the hippocampus. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to measure the expression of PKA， CaN， CaM， NCLX， MCU， and Drp1 mRNAs. ResultsCompared with those in the normal group， the recognition index （RI） of the model group decreased （P0.01）， and the number of crossings through the original platform area， the duration of stay in the target quadrant， and the distance were reduced （P0.01）. The protein expression of PKA， NCLX， and p-DRP1 （ser637） significantly decreased （P0.05）， and the mRNA expression of PKA and NCLX significantly decreased （P0.05）. The escape latency （EL） was prolonged （P0.05）， and the intracellular Ca²⁺ level significantly increased （P0.01）. The protein expression of CaN， CaM， MCU， and Drp1， as well as the mRNA expression of CaN， MCU， and Drp1， significantly increased （P0.05）. After intervention with Donepezil and Yizhi Qingxin prescription， compared with that in the model group， the RI of the treatment group significantly increased （P0.05）， and the number of crossings through the platform and the duration of stay in the target quadrant significantly increased （P0.05）. The protein expression of PKA， NCLX， and p-Drp1 （ser637） and the mRNA expression of PKA and NCLX significantly increased （P0.05）. On the 4th and 5th days， the EL was shortened （P0.05）， and the intracellular Ca²⁺ level decreased （P0.05）. The protein expression of CaN， CaM， MCU， and Drp1 and the mRNA expression of CaN， MCU， and Drp1 significantly decreased （P0.05）. ConclusionYizhi Qingxin prescription regulates the PKA/CaN pathway， upregulates the expression of PKA， NCLX， and p-Drp1 （ser637） proteins， reduces the expression of CaN， CaM， MCU， and Drp1 proteins， and regulates Ca²⁺ homeostasis and mitochondrial dynamic balance， thereby enhancing the spatial learning and memory abilities of AD mice.

ObjectiveTo explore the mechanism by which Yizhi Qingxin prescription improves mitochondrial dysfunction in Alzheimer's disease （AD） through regulating mitochondrial Ca²⁺ homeostasis and kinetic balance based on the protein kinase A （PKA）/calcineurin （CaN） signaling pathway. MethodsSixty three-month-old amyloid precursor protein （APP）/presenilin 1 （PS1） double transgenic mice were randomly divided into a model group， a donepezil group（0.65 mg·kg^-1）， a low-dose Yizhi Qingxin prescription group （YQF-L，2.6 g·kg^-1）， a medium-dose Yizhi Qingxin prescription group （YQF-M，5.2 g·kg^-1）， and a high-dose Yizhi Qingxin prescription group （YQF-H，10.4 g·kg^-1）， with 12 mice in each group. Twelve C57BL/6J mice with the same genetic background served as a normal group. Each treatment group received gavage administration daily， with the model and normal groups receiving equal volume of physiological saline. Intervention continued for 12 consecutive weeks. The learning and memory abilities of the mice were assessed using the novel object recognition （NOR） and Morris water maze （MWM） tests. Hematoxylin-eosin （HE）/Nissl staining was used to observe histopathological changes in the hippocampus. Transmission electron microscopy （TEM） was used to observe mitochondrial ultrastructure. Fluo-4 acetoxymethyl ester （Fluo-4 AM） Ca²⁺ probe was used to measure intracellular Ca²⁺ concentration in brain tissue. Western blot was used to determine the protein expression of PKA， CaN， sodium/calcium/lithium exchanger （NCLX）， mitochondrial calcium uniporter （MCU）， calmodulin （CaM）， dynamin-related protein 1 （Drp1）， and phosphorylated dynamin-related protein 1 （serine 637 site） ［p-Drp1（S637）］ in the hippocampus. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to measure the expression of PKA， CaN， CaM， NCLX， MCU， and Drp1 mRNAs. ResultsCompared with those in the normal group， the recognition index （RI） of the model group decreased （P0.01）， and the number of crossings through the original platform area， the duration of stay in the target quadrant， and the distance were reduced （P0.01）. The protein expression of PKA， NCLX， and p-DRP1 （ser637） significantly decreased （P0.05）， and the mRNA expression of PKA and NCLX significantly decreased （P0.05）. The escape latency （EL） was prolonged （P0.05）， and the intracellular Ca²⁺ level significantly increased （P0.01）. The protein expression of CaN， CaM， MCU， and Drp1， as well as the mRNA expression of CaN， MCU， and Drp1， significantly increased （P0.05）. After intervention with Donepezil and Yizhi Qingxin prescription， compared with that in the model group， the RI of the treatment group significantly increased （P0.05）， and the number of crossings through the platform and the duration of stay in the target quadrant significantly increased （P0.05）. The protein expression of PKA， NCLX， and p-Drp1 （ser637） and the mRNA expression of PKA and NCLX significantly increased （P0.05）. On the 4th and 5th days， the EL was shortened （P0.05）， and the intracellular Ca²⁺ level decreased （P0.05）. The protein expression of CaN， CaM， MCU， and Drp1 and the mRNA expression of CaN， MCU， and Drp1 significantly decreased （P0.05）. ConclusionYizhi Qingxin prescription regulates the PKA/CaN pathway， upregulates the expression of PKA， NCLX， and p-Drp1 （ser637） proteins， reduces the expression of CaN， CaM， MCU， and Drp1 proteins， and regulates Ca²⁺ homeostasis and mitochondrial dynamic balance， thereby enhancing the spatial learning and memory abilities of AD mice.

One of the technical bottlenecks limiting the high yield of 1,4-butanediamine is the insufficient tolerance of strains to 1,4-butanediamine. Enhancing the tolerance of strains to 1,4-butanediamine is therefore a primary challenge that needs to be addressed for the construction of strains with high yields of 1,4-butanediamine. Staphylococcus pasteuri 326180 exhibits exceptional tolerance to high-concentration 1,4-butanediamine, serving as both an ideal model for studying the mechanism underlying the 1,4-butanediamine tolerance and a novel host for constructing strains capable of efficiently producing 1,4-butanediamine. However, for both the research on the tolerance mechanism and the modification of chassis strains, gene editing of S. pasteuri needs to be carried out at the molecular level. The research objective of this paper is to establish a genetic manipulation system for S. pasteuri, laying foundation for subsequent studies on tolerance mechanism and the modification of chassis strains. This study systematically optimized the electroporation conditions, including key parameters such as the growth phase of cells, electric field strength, electroporation buffer, and recovery medium, successfully establishing an electroporation method for S. pasteuri. Additionally, we constructed the gene editing plasmid pCpfOA by replacing the resistance expression cassette, optimized the selection markers for gene editing, and finally established a CRISPR/Cpf1-based gene editing technology for S. pasteuri, achieving an editing efficiency of 90%. The genetic manipulation system of S. pasteuri established in this study provides technical support for research into the tolerance mechanism of this bacterium and the genetic modification of chassis strains.
Staphylococcus/drug effects* ; Gene Editing/methods* ; Electroporation/methods* ; Plasmids/genetics* ; CRISPR-Cas Systems ; Genetic Engineering/methods*

Objective To observe the alterations of protein expression of nicotinamide adenine di-nucleotide phosphatase oxidase 4-silent mating type information regulation 2 homolog 1(NOX4-SIRT1)signaling pathway in ApoE-/-mice and C57BL/6J mice induced by high-fat diet.Methods Twenty ApoE-/-mice and 40 C57BL/6J mice,aged of 10 weeks and half male and half female,were randomly divided into a NC group and a HFD group,with 10 mice in each group(ApoE-/-+NC and ApoE-/-+HFD groups,and C57+NC and C57+HFD groups).After 1 week of adaptive feed-ing period,each group was fed with their corresponding diet for subsequent 12 weeks,and then blood samples were collected from the anesthetized orbits and aortic arch tissues were harvested.HE staining and Masson staining were performed to examine the pathological morphology of the aortic arch tissues.The serum levels of TG,TC,HDL-C and LDL-C were measured using an auto-matic biochemical analyzer.The content of ox-LDLC was detected with ELISA,and the contents of ROS,GSH,GPX and NAD+were measured by colorimetry.The expression of SIRT1,p53,p21 and NOX4 was detected by Western blotting.Results Compared with the C57+NC group,the ApoE-/-+NC group showed significant lipid deposition,increased collagen fibers,elevated levels of TC,TG,HDLC,LDL-C,ox-LDL-C and ROS and increased p21 expression level,and obviously decreased contents of GSH,GPX and NAD+(P＜0.05,P＜0.01).Compared with the ApoE-/-+NC group,the ApoE-/-+HFD group showed larger plaque areas,lessened elastic fibers,more col-lagen fibers,increased levels of TC,HDL-C,LDL-C,ox-LDL-C and ROS,and p21 expression level(P＜0.01),and declined expression of GSH,GPX,NAD+and NOX4[6.4±0.8 μmol/L vs 9.6±0.8 μmol/L,242.0±39.0 U/ml vs 362.7±11.1 U/ml,0.61±0.15 nmol/L vs 1.07±0.20 nmol/L,0.26±0.01 vs 0.32±0.03;P＜0.05,P＜0.01[.Conclusion High-fat diet may accelerate vascular aging by elevating lipid and oxidative stress levels,decreasing NAD+and NOX4 expression,ele-vating p21 expression,and thereby activating the NOX4-SIRT1 pathway.

Objective To explore the efficacy and safety of 0.02％atropine eye drops for the treatment of nearwork-induced transient myopia(NITM)in adolescents.Methods A total of 131 adolescents with NITM were randomly divided into experimental(receiving 0.02％atropine eye drops)and control(receiving placebo)groups.Changes in the initial NITM values before medication and at 14 and 30 days after medication were observed.Alterations in intraocular pressure and accommodation amplitude were monitored,and the occurrence of complications,such as photophobia and near vision impairment,were recorded.Results The baseline NITM did not differ significantly between the two groups.On day 14 and day 30,the NITM values in the experimental group were significantly reduced compared to the baseline,with differences of 0.31 D±0.20 D and 0.30 D±0.16 D,which were significantly greater than those in the control group(0.21 D±0.98 D and 0.20 D±0.18 D,P＜0.001).The efficacy rate of NITM treatment in the experimental group was 84.4％,which was sig-nificantly higher than that in the control group(29.9％).After 30 days of treatment,no severe systemic or ocular adverse reactions were observed in the experimental group.Mild photophobia was the main adverse reaction.Conclusion 0.02％atropine eye drops can effec-tively reduce the initial NITM value in adolescents within a month of its use,with no severe complications and good tolerance.A clinical trial of atropine eye drops at different concentrations to reduce NITM over a longer period is warranted.

Objective To explore the efficacy and safety of 0.02％atropine eye drops for the treatment of nearwork-induced transient myopia(NITM)in adolescents.Methods A total of 131 adolescents with NITM were randomly divided into experimental(receiving 0.02％atropine eye drops)and control(receiving placebo)groups.Changes in the initial NITM values before medication and at 14 and 30 days after medication were observed.Alterations in intraocular pressure and accommodation amplitude were monitored,and the occurrence of complications,such as photophobia and near vision impairment,were recorded.Results The baseline NITM did not differ significantly between the two groups.On day 14 and day 30,the NITM values in the experimental group were significantly reduced compared to the baseline,with differences of 0.31 D±0.20 D and 0.30 D±0.16 D,which were significantly greater than those in the control group(0.21 D±0.98 D and 0.20 D±0.18 D,P＜0.001).The efficacy rate of NITM treatment in the experimental group was 84.4％,which was sig-nificantly higher than that in the control group(29.9％).After 30 days of treatment,no severe systemic or ocular adverse reactions were observed in the experimental group.Mild photophobia was the main adverse reaction.Conclusion 0.02％atropine eye drops can effec-tively reduce the initial NITM value in adolescents within a month of its use,with no severe complications and good tolerance.A clinical trial of atropine eye drops at different concentrations to reduce NITM over a longer period is warranted.

Objective To observe the alterations of protein expression of nicotinamide adenine di-nucleotide phosphatase oxidase 4-silent mating type information regulation 2 homolog 1(NOX4-SIRT1)signaling pathway in ApoE-/-mice and C57BL/6J mice induced by high-fat diet.Methods Twenty ApoE-/-mice and 40 C57BL/6J mice,aged of 10 weeks and half male and half female,were randomly divided into a NC group and a HFD group,with 10 mice in each group(ApoE-/-+NC and ApoE-/-+HFD groups,and C57+NC and C57+HFD groups).After 1 week of adaptive feed-ing period,each group was fed with their corresponding diet for subsequent 12 weeks,and then blood samples were collected from the anesthetized orbits and aortic arch tissues were harvested.HE staining and Masson staining were performed to examine the pathological morphology of the aortic arch tissues.The serum levels of TG,TC,HDL-C and LDL-C were measured using an auto-matic biochemical analyzer.The content of ox-LDLC was detected with ELISA,and the contents of ROS,GSH,GPX and NAD+were measured by colorimetry.The expression of SIRT1,p53,p21 and NOX4 was detected by Western blotting.Results Compared with the C57+NC group,the ApoE-/-+NC group showed significant lipid deposition,increased collagen fibers,elevated levels of TC,TG,HDLC,LDL-C,ox-LDL-C and ROS and increased p21 expression level,and obviously decreased contents of GSH,GPX and NAD+(P＜0.05,P＜0.01).Compared with the ApoE-/-+NC group,the ApoE-/-+HFD group showed larger plaque areas,lessened elastic fibers,more col-lagen fibers,increased levels of TC,HDL-C,LDL-C,ox-LDL-C and ROS,and p21 expression level(P＜0.01),and declined expression of GSH,GPX,NAD+and NOX4[6.4±0.8 μmol/L vs 9.6±0.8 μmol/L,242.0±39.0 U/ml vs 362.7±11.1 U/ml,0.61±0.15 nmol/L vs 1.07±0.20 nmol/L,0.26±0.01 vs 0.32±0.03;P＜0.05,P＜0.01[.Conclusion High-fat diet may accelerate vascular aging by elevating lipid and oxidative stress levels,decreasing NAD+and NOX4 expression,ele-vating p21 expression,and thereby activating the NOX4-SIRT1 pathway.

Objective To explore the mechanism of piper longum extract on liver fibrosis induced by carbon tetrachloride(CCl4)in rats.Methods Sixty SD rats were randomly divided into blank group,model group,low dose group(16.6mg/kg),middle dose group(33.3mg/kg)and high dose group(66.7mg/kg)of piper longum extract,with 12 rats in each group.Except the blank group,the other groups were subcutaneously injected with 50％CCl4 rapeseed oil solution for 8 weeks to establish liver fibrosis models.At the same time of modeling,the model group was given normal saline by gavage,and the low,middle and high dose groups of piper longum extract were given gavage for 8 weeks.After the experiment,serum alanine transaminase(ALT),aspartate aminotransferase(AST)and γ-glutamyl-transferase(γ-GT),tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6)were measured;the pathological changes of liver tissue in rats was observed by hematoxylin eosin staining and Masson's trichrome staining.The tissue total RNA was extracted and qPCR method was used to detect the mRNA expression levels of Collagen Ⅰ,α-smooth muscle actin(α-SMA)and TNF-α.Tissue protein was extracted and Western blot method was used to detect the protein expression levels of Collagen Ⅰ,α-SMA and TNF-α.Results The results of HE staining and Masson staining showed that the liver fibrosis of rats in the model group was obvious,ALT,AST and γ-GT were increased,serum inflammatory mediator TNF-α and IL-6 secretion was increased.The mRNA and protein expression levels of Collagen Ⅰ,α-SMA and TNF-α in the model group were significantly increased.Piper longum extract can significantly improve the degree of liver fibrosis.ALT,AST,y-GT were decreased,and serum inflammatory mediator TNF-α and IL-6 were decreased,the mRNA and protein expression levels of Collagen Ⅰ,α-SMA,TNF-α in liver tissue were significantly decreased.Conclusion Piper longum extract has obvious therapeutic effect on CCl4 induced liver fibrosis in rats,which can be achieved by inhibiting the inflammatory factor TNF-α and IL-6 expression,and possibly by inhibiting the activation of hepatic stellate cell,thereby reducing Collagen Ⅰ andα-SMA synthesis exerts anti fibrosis effect.

Objective Exploring the protective effect and mechanism of piperlongumine(PL),an active ingredient in the extract of Piper longum,on hepatic stellate cell damage in vitro.Methods The liver stellate cells(HSC-T6)were activated by adding lipopo-lysaccharide(LPS),and the liver stellate cells were treated with different concentrations of piperlongumine,and the protein and mRNA expression levels of IL-18,GSDMD,NLRP3 and caspase-1 in the cells were detected by Western blot and qPCR.Immunofluorescence staining showed the localization and expression of IL-18,GSDMD,NLRP3 and caspase-1 in cells.Molecular docking technology was used to analyze the target molecules of the action of piperlongumine.Results In vitro experiments showed that piperlongumine could in-hibit the protein and mRNA expression of IL-18,GSDMD,NLRP3 and caspase-1 in a concentration-dependent manner.The results of molecular docking verified the correlation,and piperlongumine could bind to IL-18,GSDMD and caspase-1,but had a poor binding effect with NLRP3.Conclusion Piperlongumine can prevent pyroptosis by inhibiting the caspase-1 signaling pathway of HSC-T6 cells,thereby exerting a protective effect on liver injury.

Objective To observe the effects of Renshen Yimai Prescription on oxidative stress and vascular aging in ApoE-/-mice;To explore its mechanism of intervention in vascular aging.Methods Forty ApoE-/-mice were divided into model group,Western medicine group(rosuvastatin,2.6 mg/kg),TCM low-and high-dosage group(Renshen Yimai Prescription,4.29,8.58 g/kg),with 10 mice in each group.Another 10 C57BL/6J mice were set as normal group.A vascular aging model was established by ApoE-/-mice fed with a Western diet.Each medication group was given corresponding drugs by gavage for 12 consecutive weeks,the normal group and model group were given equivalent volume of pure water.HE staining and Masson staining were used to observe the morphological changes of aortic tissue,and ox-LDL content in serum was detected by ELISA,the contents of ROS,GSH,GPX and NAD+in serum were detected by colorimetric method,the expressions of SIRT1,p53,p21 and NOX4 protein in aortic tissue were detected by Western blot.Results Compared with the normal group,the model group mice showed significant fat deposition in the aorta,thickening of the intima and media,a significant decrease in elastic fibers,and an increase in collagen fibers;the serum contents of ox-LDL and ROS significantly increased(P<0.01),while the contents of GSH,GPX and NAD+significantly decreased(P<0.01);the expression of SIRT1 protein in the aortic tissue significantly decreased(P<0.05),the expressions of p21 and p53 protein significantly increased(P<0.01,P<0.05).Compared with the model group,a small amount of lipid deposition was observed in the intima of aorta in each medication group,with clearer membrane structures in each layer and reduced collagen fiber;the serum contents of ox-LDL and ROS in each medication group were significantly decreased(P<0.01),while the GSH content significantly increased(P<0.05,P<0.01),the NAD+content in TCM low-dosage group significantly increased(P<0.05);the expressions of p21 and NOX4 protein in aortic tissue of the TCM high-dosage group significantly increased(P<0.05,P<0.01).Compared with the Western medicine group,the TCM high-dosage group showed a significant decrease in ROS content(P<0.01)and a significant decrease in p53 protein expression(P<0.05).Compared with the TCM low-dosage group,the TCM high-dosage group showed a significant decrease in p21 protein expression(P<0.01)and a significant increase in NOX4 protein expression(P<0.01).Conclusion Renshen Yimai Prescription may reduce vascular endothelial damage by regulating oxidative stress levels and related protein expression,thereby playing a role in improving vascular aging.