Objective To observe the pharmacokinetic effect of amoxicillin and clavulanate potassium tablets on amoxicillin in Chinese healthy subjects under fasting and high fat and high calorie diet.Methods 71 healthy subjects were given a single dose of amoxicillin potassium clavulanate tablets(0.375 g)on fasting or high fat diet,and venous blood samples were collected at different time points.The concentrations of amoxicillin in human plasma were determined by HPLC-MS/MS method,and the pharmacokinetic parameters were calculated by non-atrioventricular model using PhoenixWinNonlin 8.0 software.Results The main pharmacokinetic parameters of amoxicillin potassium clavulanate tablets after fasting and high fat diet were(5 105.00±1 444.00),(4 593.00±1 327.00)ng·mL-1,and postprandial-fasting ratio 89.40％,90％confidence interval(79.55％-100.19％);t1/2 were(1.52±0.16),(1.39±0.22)h;AUC0-t were(12 969.00±1 841.00),(11 577.00±1 663.00)ng·mL-1·h,and postdietary/fasting ratio 89.20％,90％confidence interval(83.92％-94.28％);AUC0-∞ were(13 024.00±1 846.00),(11 532.00±1 545.00)ng·mL-1·h,and postprandial-fasting ratio 88.60％,90％confidence interval(83.48％-93.50％).The median Tmax(range)were 1.63(0.75,3.00)and 2.50(0.75,6.00)h,respectively,and the Tmax of postprandial medication was delayed(P＜0.01).Conclusion Compared with fasting condition,amoxicillin Tmax was significantly delayed after high fat diet,while Cmax,AUC0-t and AUC0-∞ were not significantly changed,indicating that food could delay the absorption of amoxicillin,but did not affect the degree of absorption.

BACKGROUND:There are many treatment methods for knee osteoarthritis,among which electroacupuncture,as an important non-drug treatment,is effective in the treatment of knee osteoarthritis,but its exact mechanism is not clear. OBJECTIVE:Effect of electroacupuncture on the expression of p53 and P21 in articular cartilage and subchondral bone of aged rats with knee osteoarthritis. METHODS:Eight 6-month-old male Sprague-Dawley rats were included in the young group and sixteen 24-month-old male Sprague-Dawley rats were randomly divided into old group(n=8)and electroacupuncture group(n=8).The rats in the electroacupuncture group received electroacupuncture stimulation once a day,5 days a week,for 8 continuous weeks,and the other two groups did not do any treatment.Eight weeks later,the level of type Ⅱ collagen C-terminal peptide in peripheral blood was detected by ELISA,the morphology of left knee cartilage and subchondral bone was observed by safranin O-fast green staining,the degree of knee cartilage degeneration was evaluated by modified Mankin's score,the microstructure of left knee cartilage and subchondral bone was detected by micro-CT,and the expression levels of matrix metalloproteinase 13,P53,P21 Mrna and protein were detected by RT-PCR and western blot respectively. RESULTS AND CONCLUSION:Compared with the young group,the level of C-terminal peptide of type Ⅱ collagen in the peripheral blood was increased in the old group(P<0.05).The micro-CT results showed that the bone volume fraction,bone mineral density and the number of bone trabeculae were decreased in the old group compared with the young group(P<0.05),while the trabecular separation increased(P<0.05).Safranin O-fast green staining showed that in the old group,the surface layer of cartilage was uneven with fissures,the morphology of chondrocytes was irregular and stained unevenly,the boundary between the cartilage and subchondral bone was blurred,and the matrix loss was serious.The Mankin's score was higher in the old group than the young group(P<0.05).The expression of matrix metalloproteinase 13,P53,P21 at Mrna and protein levels increased in the old group compared with the young group(P<0.05).Compared with the old group,electroacupuncture decreased the level of C-terminal peptide of type Ⅱ collagen(P<0.05),increased the bone volume fraction,bone mineral density and the number of bone trabeculae(P<0.05),and decreased the trabecular separation(P<0.05).Safranin O-fast green staining showed that in the electroacupuncture group,the surface of cartilage was smooth and red staining was uniform,and the cell morphology and structure were between the young group and the old group.Following electroacupuncture treatment,the Mankin's score(P<0.05),matrix metalloproteinase 13 and P21 Mrna expression(P<0.05),and matrix metalloproteinase 13 and P53 protein expression decreased(P<0.05),while there was a decreasing trend of P53 Mrna and P21 protein expression,but with no statistical significance(P>0.05).To conclude,electroacupuncture may delay articular cartilage degeneration and subchondral osteoporosis in aged rats by inhibiting the expression of P53 and P21,so as to protect joints and delay joint aging.

OBJECTIVE To investigate the effects of Tongxie yaofang （TXYF） on the symptoms of rats with irritable bowel syndrome with diarrhea （IBS-D） by regulating colonic tryptophan hydroxylase 1 （TPH1）， serotonin transporter （SERT） and intestinal flora. METHODS Forty-two SD rats were randomly divided into control group （7 rats） and modeling group （35 rats）. In modeling group， rat model of IBS-D was established by intragastrical administration of 0.45 g/L senna leaf solution [10 mL/（kg·d）] combined with chronic unpredictable stimulation. Thirty-five successfully modeled rats were randomly divided into model group， pinaverium bromide group [15 mg/（kg·d）] and TXYF low-dose， medium-dose and high-dose groups [3.75、7.5、15 g/（kg·d）， calculated by crude drug]， with 7 rats in each group. Each administration group was orally administered the corresponding drug， once a day， for 10 consecutive days. The general condition and weight changes of each group of rats were compared before modeling， after modeling and before administration， after the last drug intervention； the diarrhea index and visceral sensitivity were detected， and pathological changes of colon tissue were observed after modeling and before administration， after the last drug intervention. The level and expression of 5-hydroxytryptamine （5-HT）， protein and mRNA expressions of TPH1 and SERT were determined in colon tissue. The diversity and structural changes of fecal intestinal flora of rats were analyzed. RESULTS There was no significant change in colon histopathology in each group. Compared with model group， the general condition of rats in each medication group improved. The daily body weight gain of rats was significantly increased， while diarrhea index， visceral sensitivity， the expressions of 5-HT and TPH1 in colon tissue were significantly decreased； SERT expression of colon tissue was significantly increased in TXYF medium-dose and high-dose groups （P＜0.05 or P＜0.01）. The diarrhea index， colon TPH1 protein expression and colon 5-HT protein positive rate in the TXYF low-dose group decreased while the mRNA expression of SERT increased significantly （P＜0.05）. There was a dose- dependent trend in the effect of TXYF. Compared with model group， Chao1 index and Shannon index of the rats in TXYF high- dose group were significantly decreased （P＜0.05 or P＜0.01）， the beneficial bacteria such as Firmicutes and Lactobacillus increased significantly， while the pathogenic bacteria such as Proteobacteria， Escherichia-Shigella and Rikenellaceae_RC9_gut_ group decreased significantly （P＜0.05 or P＜0.01）. CONCLUSIONS TXYF can decrease the level of 5-HT and improve intestinal flora disorder by inhibiting the expression of TPH1 and up-regulating the expression of SERT in colon tissue， thus promoting the symptoms of IBS-D rats.

Natural products are important sources of drug discovery. However, the traditional methods of extraction and isolation, as well as chemical synthesis for obtaining natural products are associated with issues such as operational complexity, high costs, low efficiency, and environmental pollution. Constructing microbial cell factories through synthetic biology methods to produce medicinal natural products has the advantages of high efficiency, low cost, and environmental protection. Nevertheless, the scope and yield improvement of the products are limited by the limitations of enzymes in microbial cell factories. Protein engineering is considered one of the most effective approaches to overcome these limitations. This article introduces commonly used methods of protein engineering technology and summarizes its specific applications in improving enzyme performance, modifying the enzymatic environment, and promoting the development of synthetic biology tools in the field of pharmaceutical natural product synthesis. Furthermore, it analyzes the current bottlenecks and challenges in protein engineering and looks forward to its future application prospects, offering insights for the development and practical use of protein engineering technology.

The breakage pattern of unit particles during the production of oral solid dosage forms (OSD) is closely related to the quality of intermediate or final products. To accurately characterize the particles and study the evolution law of particle breakage, the Bonding model of the discrete element method (DEM) was used to investigate the breakage patterns of model parameters, particle shape and process conditions (loading mode and loading rate) on the dynamic breakage, force-time curve, breakage rate, maximum breakage size ratio and fracture strength of particles. The results showed that the particle breakage force was positively correlated with normal strength and bonded disk scale, negatively correlated with normal stiffness per unit area and tangential stiffness per unit area, and weakly correlated with tangential strength. The particle breakage rate was negatively correlated with the aspect ratio of the particles, and the maximum breakage size ratio was positively correlated with the aspect ratio of the particles; among the three loading modes, the breakage rate of compression breakage model was the largest, the breakage rate of shear breakage model was the second largest, and the breakage rate of wear breakage model was the smallest; the maximum breakage size ratio was positively correlated with the loading rate, the loading mode and the loading rate had no mutual influence on particle breakage rate, but had mutual influence on the maximum breakage size ratio. The research results will provide a theoretical basis for the shift of OSD from batch manufacturing to advanced manufacturing.

Objective: To investigate the association between early life adversity(ELA) and the triglycerideglucose (TyG) index for an indicator of insulin resistance among girls with precocious puberty, so as to provide scientific basis for effective prevention and intervention measures. Methods: From July 2020 to September 2021, girls with precocious puberty were recruited from the childrens health clinic of Anhui Provincial Childrens Hospital. Among them, 150 girls with complete blood indicators and questionnaire information were included. Both parental reports and child selfreports were combined to assess ELA exposure. Fasting blood samples were collected to evaluate thetyg index. According to the ELA score classification, girls were classified into 3 groups for 0, 1 and >2, multiple linear regression analysis were conducted to examine the association between ELA exposure and TyG index in girls with precocious puberty. Results: Precocious pubertal girls subjectively reported high rates of ELA exposure, with an average ELA score of (1.07±1.17) and an average TyG level of (7.99±0.49). A single adverse association was found that the exposure of girls with precocious puberty to a lack of warm nurturing was significantly positively correlated with the TyG index (β=0.26, 95%CI=0.03-0.50, P<0.05). Multiple linear regression analysis showed that girls in the ELA≥2 group had a 0.24 increase in TyG levels compared to girls who did not experience ELA (β=0.24, 95%CI=0.04-0.43). After controlling for covariates such as child age, mothers age, fathers age, physical activity, screen time, birth weight, birth method (including natural and cesarean sections), perceived stress, BMI standardized Zscore, and parental assessment SDQ score, The association remained significant after controlling for covariates and was independent of BMI (β=0.25, 95%CI=0.04-0.46)(P<0.05). Conclusions Cumulative early life adversity in girls with precocious puberty is significantly positively correlated with the TyG index. It should early identify the girls exposed to high ELA for precocious puberty and timely intervent to improve their glucose metabolism function.

Objective To exploring the effect of human amniotic mesenchymal stem cells(hAMSCs)on the re-pair of rat uterine scars.Methods The hAMSCs were isolated and cultured,Female SPF grade SD rats were selected for full-thickness incision of uterine wall and then implanted with hAMSCs.On the 30th day after op-eration,the uterine incision was examined histologically.ImageJ image analysis software was used to analyze and to compare the thickness of uterine myometrium and the percentage of fibrotic area in each group.Immuno-histochemical method was used for detecting the percentage of positive areas of α-SMA,TGF-β1,and Ki-67.Results Compared with the PBS group,the hAMSCs group showed significant thickening of the uterine mus-cle layer and fibrotic area was decreased,The positive expression of α-SMA,and Ki-67 significantly increased(P＜0.05),while the expression of TGF-β1 was significantly reduced(P＜0.05).Conclusions The hAMSCs may promote the repair of uterine incision scars by reducing the formation of scar fibrosis and promoting the proliferation of smooth muscle cells in uterine scars.

Objective To analyze the incidence and mortality of malignant tumors among the middle-aged and elderly population in Chengguan district of Lanzhou from 2011 to 2021,and to discuss the related risk factors.Methods Using the research data of REACTION in Lanzhou,an epidemiological survey was conducted through cluster sampling in three communities in Chengguan district of Lanzhou since April 2011.The target population was middle-aged and elderly residents over 40 years old.Two follow-up surveys were carried out in 2014-2016 and 2021 successively,and 6543 people with complete follow-up data were finally included.The incidence and mortality rates of malignant tumors were calculated,as well as their age standardized rates with reference to the age composition of Segi's world standard population.Multivariate Cox regression analysis was used to screen the risk factors affecting the incidence and mortality of malignant tumors.Results After an average follow-up of 10.6 years,314 new cases of malignant tumors were found in middle-aged and elderly residents in Chengguan district of Lanzhou,with an incidence rate and age standardized incidence rate of 454.30/100 000 and 128.93/100 000,respectively.A total of 158 deaths were attributed to malignant tumors,with a mortality rate and age standardized rate of 228.41/100 000 and 607.9/100 000,respectively;The age standardized incidence rate and mortality rate of malignant tumors males were both higher than those females(P＜0.05).During the follow-up period,the age standardized incidence rate of malignant tumors in the general population showed an significant upward trend(P＜0.05),whereas the age standardized mortality rate gradually decreased after a brief increase(P＜0.05).Lung cancer,colorectal cancer,gastric cancer,and liver cancer were the main types of malignant tumors ranking in the top five in terms of incidence and mortality by gender.Multivariate Cox regression results indicate that male,age≥60 years old,college education level or above,smoking history,drinking history,having been hit by major stressful events,central obesity,hypertension,and coronary heart disease are risk factors for the onset or death of malignant tumors(HR＞1).Married,with family size≥4,frequent consumption of fresh fruit,frequent consumption of fresh vegetables,frequent consumption of grains and tubers are protective factors for the onset or death of malignant tumors(HR＜1).Conclusion The incidence of malignant tumors among middle-aged and elderly people in Chengguan district of Lanzhou from 2011 to 2021 showed an increasing trend,while the overall mortality was decreasing.Our study indicates early cancer screening in elderly populations,maintaining a healthy lifestyle and strengthening the management of chronic diseases are crucial for the prevention and treatment of malignant tumors.

Objective:To investigate the correlation between thyroid hormone resistance and hyperuricemia in euthyroid population.Methods:It was a cross-sectional study. A total of 548 euthyroid subjects who were hospitalized or underwent physical examination in the Heart Center and Health Management Center of the First Affiliated Hospital of Tsinghua University from January 2021 to December 2022 were selected. Thyroid function, uric acid, blood lipid and other indicators were collected in the subjects, and thyroid function parameters were calculated: thyroid-stimulating hormone index (TSHI), thyrotropin T4 resistance index (TT4RI), parametric thyroid feedback quantile-based index (PTFQI), free triiodothyronine/free thyroxine (FT3/FT4), the sum activity of peripheral deiodinases (SPINA-GD) and the secretory capacity of the thyroid gland (SPINA-GT). According to uric acid level, the subjects were divided into high uric acid group and normal group, the clinical characteristics and thyroid function parameters of the two groups were compared, the correlation between thyroid hormone resistance and hyperuricemia was further explored.Results:Compared with the normal group, male proportion (94.4% and 52.5%), smoking rate (5.2% and 21.3%), body mass index [(27.10±3.96) and (24.26±3.42) kg/m 2], waist-to-hip ratio [0.90(0.86, 0.94) and 0.86(0.80, 0.91)], serum creatinine [(85.50±12.27) and (73.77±28.79) μmol/L], total cholesterol [(5.08±0.99) and (4.72±0.86) mmol/L], triglyceride [2.10(4.40, 5.59) and 1.14(0.79, 1.67)mmol/L], low-density lipoprotein [(3.19±0.97) and (2.85±0.84) mmol/L] and homocystine [(15.07±9.13) and (12.50±10.85) μmol/L] were all higher in the high uric acid group, and the level of high-density lipoprotein [1.15(1.43, 2.88) and 1.39(1.16, 1.64) mmol/L] was lower (all P<0.05). In the aspect of thyroid hormone and thyroid function parameters, the FT4[16.90(5.40,17.95) and 16.00(14.30,17.80) pmol/L], FT3[5.56(5.25, 5.94) and 5.22(4.81, 5.63) pmol/L], FT3/FT4 [0.34(0.31, 0.37) and 0.32(0.29, 0.36)], TSHI (2.70±0.50 and 2.58±0.60), PTFQI (0.406±0.332 and 0.335±0.353) and SPINA-GD [3.72(3.41, 4.05) and 3.52(3.18, 4.00) ]were all higher in high uric acid group than those in normal group(all P<0.05). Spearman correlation analysis showed that blood uric acid level was positively correlated with FT4 ( r=0.185), FT3 ( r=0.422), FT3/FT4 ( r=0.16), TSHI ( r=0.134), TT4RI ( r=0.09), PTFQI ( r=0.121) and SPINA-GD ( r=0.157) (all P<0.05). Conclusion:In people with euthyroid function, central resistance to thyroid hormone is correlated with hyperuricemia.

AIM: To evaluate the efficacy and safety of different Conbercept treatment on diabetic macular edema(DME)with 3+PRN and 5+PRN.METHODS: Retrospective case-control study. A total of 51 patients(92 eyes)with DME who were treated in our hospital during December 2019 and June 2020 were included, and they were divided into 3+PRN group with 26 cases(48 eyes)and 5+PRN group with 25 cases(44 eyes). All patients received monthly follow-up for 12mo and the changes of best-corrected visual acuity(BCVA)and central macular thickness(CMT), the number of intravitreal injections and the occurrence of complications were compared and observed in the two groups.RESULTS:After follow-up for 12mo, there was no difference in the average injection times between the 3+PRN group and the 5+PRN group(7.24±0.91 times vs. 7.56±1.04 times, P=0.117). The BCVA and CMT of the two groups improved at 3, 6, 9, and 12mo after treatment compared with those before treatment(all P<0.05), and the BCVA and CMT of the 5+PRN group were better than those of the 3+PRN group at 6, 9, and 12mo after treatment(all P<0.05). During the follow-up period, no serious adverse events occurred in the two groups of patients, and the total incidence of ocular adverse events in the two groups was 27%. All adverse events were improved after symptomatic treatment.CONCLUSION: Both the 3+PRN and 5+PRN treatment strategy of Conbercept can treat DME safely and effectively, the total times of injection were comparable. However, the BCVA and CMT improved more in the 5+PRN group than that in 3+PRN group.