BACKGROUND:Osteoporosis is a high-risk factor for dental implant treatment.The preparation of tissue engineering scaffolds with sustained-release Alendronate and its application in oral implant surgery for osteoporosis patients is a current hot topic in oral bone tissue engineering research.OBJECTIVE:To prepare alendronate/chitosan/polyvinyl alcohol composite hydrogel film and characterize its sustained release properties.METHODS:(1)Chitosan/polyvinyl alcohol composite hydrogel films with varying mass ratios(mass ratios of chitosan and polyvinyl alcohol were 3:7,5:5,and 7:3,respectively),chitosan and polyvinyl alcohol hydrogel films were prepared using a physical crosslinking method.By characterizing the morphology,water contact angle,mechanical properties,swelling rate,and cell compatibility of the hydrogel film,a suitable hydrogel film was screened as a carrier of alendronate.(2)Chitosan/polyvinyl alcohol composite hydrogel films containing 0,0.4,1.2,and 2.0 mg/L alendronate were prepared,and rat bone marrow mesenchymal stem cells were co-cultured with the four groups of hydrogel films.The cytocompatibility of the hydrogel films was detected by CCK-8 assay and CD44 immunofluorescence staining.The drug-loaded chitosan/polyvinyl alcohol composite hydrogel films were immersed in PBS.The drug release performance of the composite hydrogel films was detected by ultraviolet-visible spectroscopy.RESULTS AND CONCLUSION:(1)The characterization results showed that with the increase of the mass of polyvinyl alcohol in the hydrogel film,the structural density of the hydrogel film increased,the porosity decreased,the water contact angle(all within 90°),the elongation at break and the compressive strength increased,and the equilibrium swelling rate decreased.It had no effect on the proliferation of rat bone marrow mesenchymal stem cells.Chitosan hydrogel film could promote the adhesion of rat bone marrow mesenchymal stem cells.The 3:7 and 5:5 ratio composite hydrogel films did not affect the adhesion of rat bone marrow mesenchymal stem cells.Polyvinyl alcohol hydrogel film and 7:3 ratio composite hydrogel film inhibited the adhesion of rat bone marrow mesenchymal stem cells.Based on the above results,the 5:5 composite hydrogel film was selected as the carrier of alendronate.(2)CCK-8 assay results showed that the composite hydrogel film containing 0.4 and 1.2 mg/L alendronate had no cytotoxicity.CD44 immunofluorescence staining results showed that the composite hydrogel film containing 0.4 mg/L alendronate did not affect the adhesion of rat bone marrow mesenchymal stem cells,while the composite hydrogel film containing 1.2 and 2.0 mg/L alendronate inhibited the adhesion of rat bone marrow mesenchymal stem cells.Chitosan/polyvinyl alcohol composite hydrogel film containing 0.4,1.2,and 2.0 mg/L alendronate released alendronate in the first 6 hours,and then released alendronate evenly and stably,with a release time of more than 96 hours.(3)The results showed that the chitosan/polyvinyl alcohol composite hydrogel film with a ratio of 5:5 had good physical and chemical properties and cytocompatibility,and could be used as a sustained-release carrier of alendronate.

Aim To clarify the mechanism by which Qishen Yixin Granules improved microcirculation vas-cular endothelial dysfunction(VED)in mice,through activating the Nrf2/HO-1 signaling pathway to regulate oxidative stress.Methods C57 mice were randomly divided into six groups:blank group,model group,pos-itive drug group,and low-,medium-,and high-dose groups of Qishen Yixin Granules.The VED model was established by long-term infusion of Ang Ⅱ combined with a high-fat diet.Each treatment group received the corresponding drug intervention.After four weeks of drug intervention,cardiac function was assessed by echocardiography.Carstairs staining was used to ob-serve the formation of microthrombi in myocardial tis-sue.The micro vascular ischemia was evaluated by Hei-denhain staining.The ultrastructure of endothelial cells was observed by electron microscopy.The levels of EMPs,ROS,NO,ET-1,TF,TM,VWF,and TXA2 in serum were measured by ELISA.The expression levels of MDA,SOD,and GSH-Px in mouse heart tissue were determined by chemical methods.Cardiac microvascu-lar density and the expression of Nrf2,Keap1,and HO-1 proteins were detected by Immunohistochemical stai-ning.The protein expressions of Keap1,cytoplasmic Nrf2,nuclear Nrf2,and HO-1 in myocardial tissue were detected by Western blot.Results Qishen Yixin Granules could effectively improve the cardiac function of mice,alleviate the damage of endothelial cells and endothelial function.They could up-regulate serum NO levels and the activities of antioxidant enzymes SOD and GSH-Px,while down-regulating the expression of ROS and vascular inflammatory injury factors such as ET-1,VWF,TXA2,TF,TM,and EMPs.Qishen Yixin Granules also increased the positive counts of CD34,Nrf2,and HO-1,as well as microvessel density.Fur-thermore,they inhibited the expression of MDA,Keap1,and cytoplasmic Nrf2 protein in myocardial tis-sue,while increasing the expression of nuclear proteins HO-1 and Nrf2.Conclusions Qishen Yixin Granules may inhibit oxidative stress and inflammatory response by regulating the Nrf2/HO-1 signaling pathway,thereby improving vascular endothelial damage and cardiac function in VED mice.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

BACKGROUND:Osteoporosis is a high-risk factor for dental implant treatment.The preparation of tissue engineering scaffolds with sustained-release Alendronate and its application in oral implant surgery for osteoporosis patients is a current hot topic in oral bone tissue engineering research.OBJECTIVE:To prepare alendronate/chitosan/polyvinyl alcohol composite hydrogel film and characterize its sustained release properties.METHODS:(1)Chitosan/polyvinyl alcohol composite hydrogel films with varying mass ratios(mass ratios of chitosan and polyvinyl alcohol were 3:7,5:5,and 7:3,respectively),chitosan and polyvinyl alcohol hydrogel films were prepared using a physical crosslinking method.By characterizing the morphology,water contact angle,mechanical properties,swelling rate,and cell compatibility of the hydrogel film,a suitable hydrogel film was screened as a carrier of alendronate.(2)Chitosan/polyvinyl alcohol composite hydrogel films containing 0,0.4,1.2,and 2.0 mg/L alendronate were prepared,and rat bone marrow mesenchymal stem cells were co-cultured with the four groups of hydrogel films.The cytocompatibility of the hydrogel films was detected by CCK-8 assay and CD44 immunofluorescence staining.The drug-loaded chitosan/polyvinyl alcohol composite hydrogel films were immersed in PBS.The drug release performance of the composite hydrogel films was detected by ultraviolet-visible spectroscopy.RESULTS AND CONCLUSION:(1)The characterization results showed that with the increase of the mass of polyvinyl alcohol in the hydrogel film,the structural density of the hydrogel film increased,the porosity decreased,the water contact angle(all within 90°),the elongation at break and the compressive strength increased,and the equilibrium swelling rate decreased.It had no effect on the proliferation of rat bone marrow mesenchymal stem cells.Chitosan hydrogel film could promote the adhesion of rat bone marrow mesenchymal stem cells.The 3:7 and 5:5 ratio composite hydrogel films did not affect the adhesion of rat bone marrow mesenchymal stem cells.Polyvinyl alcohol hydrogel film and 7:3 ratio composite hydrogel film inhibited the adhesion of rat bone marrow mesenchymal stem cells.Based on the above results,the 5:5 composite hydrogel film was selected as the carrier of alendronate.(2)CCK-8 assay results showed that the composite hydrogel film containing 0.4 and 1.2 mg/L alendronate had no cytotoxicity.CD44 immunofluorescence staining results showed that the composite hydrogel film containing 0.4 mg/L alendronate did not affect the adhesion of rat bone marrow mesenchymal stem cells,while the composite hydrogel film containing 1.2 and 2.0 mg/L alendronate inhibited the adhesion of rat bone marrow mesenchymal stem cells.Chitosan/polyvinyl alcohol composite hydrogel film containing 0.4,1.2,and 2.0 mg/L alendronate released alendronate in the first 6 hours,and then released alendronate evenly and stably,with a release time of more than 96 hours.(3)The results showed that the chitosan/polyvinyl alcohol composite hydrogel film with a ratio of 5:5 had good physical and chemical properties and cytocompatibility,and could be used as a sustained-release carrier of alendronate.

Dark plum can be used to treat symptoms such as consumptive thirst due to deficiency-heat and chronic cough due to lung deficiency.Its active ingredients have auxiliary effects on lowering blood glucose,antibacterial and anti-inflammatory activities.Insulin resistance is mainly characterized by the weakening of the physiological effects of insulin in the body,with a relatively complex mechanism that can lead to various metabolic-related diseases and seriously affect health.The active ingredients of dark plum can improve insulin resistance by regulating insulin signaling pathways,endoplasmic reticulum stress,antioxidant stress,inflammatory signaling pathways,levels of related inflammatory mediators,and free fatty acid levels.By reviewing the relevant literature on the improvement of insulin resistance by the active ingredients of dark plum,this article summarizes and analyzes its mechanism of action,aiming to provide new ideas and scientific evidence for in-depth research on insulin resistance and the development and application of drugs.

Objective To develop dynamic prediction models based on multiple postnatal time points to support early diagnosis and individualized intervention for bronchopulmonary dysplasia(BPD)in preterm infants with gestational age<32 weeks.Methods Clinical data of 472 preterm infants with gestational age<32 weeks admitted to the Second Xiangya Hospital of Central South University between January 2016 and November 2020 were retrospectively analyzed.Multivariable logistic regression was applied to develop five independent prediction models at postnatal days 1,7,14,21,and 28.The performance of the models was assessed using the area under the receiver operating characteristic curve(AUC)and the Hosmer-Lemeshow test.Results Baseline characteristics such as gestational age and birth weight differed significantly between the BPD group(n=147)and the non-BPD group(n=325)(P<0.05).Predictors of BPD evolved across time points:on day 1,key predictors included gestational age,birth weight,Score for Neonatal Acute Physiology II(SNAP-II),invasive mechanical ventilation,and fraction of inspired oxygen>30%;by day 7,additional variables emerged,including fasting duration>2 days,mean feeding advancement rate<8.5 mL/(kg·d),neonatal respiratory distress syndrome,apnea of prematurity,and positive sputum culture;from day 14 onward,nutrition-and treatment-related indicators were incorporated additionally.The models demonstrated good discrimination at postnatal days 1,7,14,21,and 28,with AUCs of 0.917,0.927,0.939,0.944,and 0.968,respectively,and good calibration(Hosmer-Lemeshow P>0.05).Internal validation showed AUCs ranging from 0.899 to 0.958,indicating robust performance.Conclusions Dynamic postnatal prediction models incorporating indicators spanning perinatal factors,respiratory support,nutritional management,and therapeutic interventions demonstrate high predictive performance and facilitate dynamic risk assessment for BPD in preterm infants with gestational age<32 weeks.

Depression is a prevalent mental and emotional disor-der that often results in significant emotional disturbances,cog-nitive dysfunction,and memory impairments.It is characterized by a high incidence rate,a substantial disability burden,and limited therapeutic efficacy.Currently,the long-term use of medications for the treatment of depression can result in a range of adverse reactions,highlighting the urgent need to explore no-vel approaches that can effectively alleviate depressive symptoms while minimizing side effects.Curcumin,a natural polyphenolic compound derived from the rhizome of turmeric,demonstrates considerable potential in the prevention and treatment of depres-sion,owing to its diverse array of biological activities.In recent years,numerous studies have investigated the use of curcumin for the treatment of depression.This article aims to provide a comprehensive review of the mechanisms of action underlying curcumin's efficacy in treating depression.Specifically,it focu-ses on its ability to improve neurotransmitter imbalances,restore neural plasticity,alleviate neural damage,mitigate dysfunction of the hypothalamic-pituitary-adrenal(HPA)axis,regulate in-flammatory factors and neuroinflammatory signaling pathways,and inhibit oxidative stress.This review is intended to offer in-sights and methodological references for basic research on curcu-min,as well as for the development of novel therapeutic agents for the treatment of depression.