The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a serious impact on global public health and the economy. SARS-CoV-2 infiltrates host cells via its surface spike protein, which binds to angiotensin-converting enzyme 2 on the host cell membrane. As a result, small molecules targeting spike protein have emerged as a hotspot in anti-SARS-CoV-2 drug research. Activity screening is an important step in seeking small molecule drugs. Therefore, this article aims to review the biological activity evaluation methods of small molecule inhibitors targeting SARS-CoV-2 spike protein, with the goal of laying the foundation for the discovery of new anti-SARS-CoV-2 drugs.

BACKGROUND:Our previous studies found that the polypeptide of Cornus cervi Colla can promote bone growth,which has a good application prospect in the treatment of bone diseases.However,how Cornus cervi Colla works in the body and the principle are not clear. OBJECTIVE:To study the in vivo distribution and tracing of Cornus cervi Colla using fluorescence labeling and tracer technique. METHODS:Cornus cervi Colla was fluorescently labeled using fluorescein isothiocyanate,and the labeling results were detected by fluorescence imaging and UV spectral scanning.Successfully labeled Cornus cervi Colla was injected into mice by gavage,and the absorption of Cornus cervi Colla into blood was detected by laser confocal microscopy,and the distribution of Cornus cervi Colla in mice was detected by small animal in vivo imager.The distribution of Cornus cervi Colla in the mice was detected by laser confocal microscopy.Samples were taken from serum and bone at the time of the strongest fluorescence,and gel electrophoresis was carried out on serum and bone tissue protein solutions,and the components of Cornus cervi Colla absorbed into target organs were determined by secondary mass spectrometry. RESULTS AND CONCLUSION:The fluorescent markers were successfully separated by dextran gel chromatography,and the fluorescence imaging and ultraviolet spectrum scanning proved that the labeling was successful,and the fluorescence substitution degree of FITC-labeled Cornus cervi Colla was 0.953%.The fluorescence intensity of the components of Cornus cervi Colla in the blood showed that Cornus cervi Colla was most distributed in serum after oral administration for 2 hours.The fluorescence images of mice at different times were the same as those of bilateral femur and tibia,indicating that Cornus cervi Colla could play a role by entering the bone.Compared with UniProt database,secondary mass spectrometry showed that the peptide was a characteristic fragment of decorin.It is proved that decorin in Cornus cervi Colla can enter the bone to play a therapeutic role.

Objective To discuss the application of the"rotating guidewire and correcting the filter recovery hook direction technique"("rotation-correction loop technique"for short),a technique invented by the authors in clinical practice,in the retrieval of complex inferior vena cava filter(IVCF),and to discuss its technical skills and advantages.Methods The clinical data of 417 patients carrying an IVCF,who were admitted to the Department of Vascular Surgery of Second Hospital of Shanxi Medical University of China to retrieve IVCF between January 2022 and December 2022,were retrospectively analyzed.Taking the time spent on the retrieval of IVCF and the intraoperative radiation dose as the evaluation indicators,the advantages and disadvantages of the standard filter retrieval technique,the"rotation-correction loop technique"and the other loop-assisted techniques were compared.Results Both the intraoperative radiation dose and the time spent on the retrieval of IVCF using"rotation-correction loop technique"were remarkably lower than those of other loop-assisted techniques(P＜0.000 1).Conclusion For the retrieval of complex IVCF,especially for the IVCF which is heavily tilted and/or its recovered hook is attached to the vascular wall,the use of"rotation-correction loop technique"can shorten the time spent on the the retrieval of IVCF and reduce the intraoperative radiation dose.This technique carries high safety and practicability,the device is simple and it can be manipulated by single physician,which is conducive to clinical application and promotion.(J Intervent Radiol,2024,33:289-294)

Objective To evaluate the pharmacokinetics(PK)of tenofovir alafenamide Fumarate tablets(25 mg)in healthy Chinese subjects after single oral administration to provide a basis for bioequivalence evaluation.Methods Using a single-dose,randomized,open-lable,two-period,two-way crossover design under fasting condition,while three-way crossover design under fed condition,42 healthy subjects respectively for fasting and fed study were enrolled,and randomized into two groups to receive a single dose of test product(T)or reference product(R)25 mg.Plasma concentration of tenofovir alafenamide and tenofovir were determined by liquid chromatography-tandem mass spectrometry(LC-MS/MS)method.The pharmacokinetic parameters were calculated by WinNonlin software(8.1 version)using non-compartmental model,and bioequivalence evaluation was performed for the two preparations.Relevant safety evaluations were performed during the trial.Results The test product and the reference product under fasting study,the main PK parameters of tenofovir alafenamide were as follows:Cmax were(215.17±94.24)and(199.30±71.11)ng·mL-1;AUC0-t were(135.44±71.60)and(123.91±53.82)h·ng·mL-1;the main PK parameters of tenofovir were as follows:Cmax were(7.30±2.27)and(7.12±1.74)ng·mL-1,AUC0-t of tenofovir were(237.16±47.09)and(230.06±43.41)h·ng·mL-1,respectively.The test product and the reference product under fed study,the main PK parameters of tenofovir were as follows:Cmax were(197.69±82.19)and(197.10±110.54)ng·mL-1;AUC0-t were(197.69±82.19)and(197.10±110.54)h·ng·mL-1;the main PK parameters of tenofovir were as follows:CMax were(2.57±1.37)and(2.58±1.31)ng·mL-1;AUC0-t were(227.08±74.33)and(238.51±128.30)h·ng·mL-1,respectively.The 90％confidence interval for geometric mean ratio of Cmax,AUC0-tof T and R under fed condition were between 80.00％-125.00％,respectively.The incidence of adverse events in fasting and fed tests was 21.43％and 30.95％,respectively,and no serious adverse event was reported.Conclusion The test formulation and reference formulation of tenofovir alafenamide fumarate tablets were equivalent and was safe.

Objective To observe the influence of thymosin α1 injection combined with capecitabine and oxaliplatin(XELOX)regimen on circulating tumor cell(CTC)and serum carcinoembryonic antigen(CEA),serum carbohydrate antigen 19-9(CA19-9)and CA125 levels in patients with colorectal cancer surgery.Methods Patients who received laparoscopic radical resection of colorectal cancer were divided into control group and treatment group by adopting cohort method.The control group was treated with XELOX regimen adjuvant chemotherapy;and on the 1st day,135 mg·m-2of oxaliplatin was intravenously dripped for 3 h;and capecitabine tablets were taken orally at 1 000 mg·m-2 twice a day for 2 weeks and discontinued for 1 week.On the basis of the treatment in the control group,the treatment group was added with subcutaneous injection of 1.6 mg of thymosin α1 once a day.Both groups were treated for 6 courses with 3 weeks as a course of treatment.CTC count,serum tumor markers,peripheral blood T lymphocyte subsets,serum inflammatory factors,quality of life,safety and progression-free survival rate and overall survival rate at 2 years after surgery were compared between groups.Results Finally,56 cases in treatment group and 50 cases in control group were included.The progression-free survival rates in treatment group and control group at 2 years after surgery were 87.50％(49 cases/56 cases)and 70.00％(35 cases/50 cases),respectively(P＜0.05).After treatment,the CTC counts in treatment group and control group were 1.21±0.39 and 1.52±0.46;serum CEA levels were(18.52±4.17)and(23.26±4.84)μg·L-1;the CA19-9 levels were(63.94±10.22)and(69.73±12.35)U·L-1;the CA125 level were(40.66±9.29)and(46.79±10.24)U·L-1;the peripheral blood CD4+/CD8+ratios were(1.38±0.18)and(1.24±0.16);serum interleukin-6(IL-6)levels were(32.04±5.57)and(37.26±6.18)ng·L-1;tumor necrosis factor-α(TNF-α)levels were(43.96±4.83)and(51.83±5.97)ng·L-1;the Karnofsky performance status(KPS)scores were(86.77±6.91)and(82.23±5.32)points;the cancer quality of life core 30(QLQ-C30)scores were(69.12±9.76)and(75.06±9.84)points(all P＜0.05).During treatment,the neutropenia rates in treatment group and control group were 48.21％and 76.00％,and abnormal rates of liver function were 10.71％and 40.00％,respectively(all P＜0.05).Conclusion Thymosin α1 injection combined with XELOX regimen adjuvant chemotherapy after colorectal cancer surgery can effectively reduce the levels of serum CEA,CA19-9 and CA125,and can improve the cellular immune function and enhance the quality of life.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

Traumatic fractures and stress fractures are common orthopedic diseases,and there is great potential in researching bone turnover,repair,and promotion of fracture healing.Basic medical experiments often use animal models of long bone fractures in limbs to study the mechanisms of various interventions on fracture healing.Fracture healing is a complex process influenced by multiple factors and involves multiple molecules and pathways.Therefore,to explore the mechanisms more deeply,accelerate the translation of results,and improve the clinical efficacy,it is particularly important to choose the appropriate animal fracture modeling methods in experimental research.Based on this,this paper conducts a literature review of animal species and modeling methods commonly used for long bone fracture models in experimental research.It summarizes five methods:bone defect method,physical impact method,mechanical bending method,open osteotomy method,and drilling method.A side-by-side comparison of their advantages,disadvantages,and scope of application is made,aiming to provide suitable fracture models for studyingthe mechanisms of fracture healing interventions.

Objective To understand the consumption of hand hygiene(HH)products and HH compliance in in-tensive care units(ICUs)of secondary and higher grade medical institutions(MIs)in Shanghai,and provide basis for further monitoring of HH among health care workers(HCWs).Methods Through healthcare-associated infec-tion surveillance system,the consumption of HH products and HH compliance in ICUs from secondary and higher grade MIs in Shanghai in 2017-2021 were analyzed.Results 105 ICUs from 74 MIs were included in analysis,the average consumption of HH products was 79.24(44.88-258.63)mL/(bed·day),with statistically significant difference among different types of ICUs(P＜0.001).The average consumption of HH products increased from 65.75 mL/(bed·day)in 2017 to 87.55 mL/(bed·day)in 2021,showing an increasing trend year by year(P＜0.001).HCWs'HH compliance rate was 82.13％,with the highest in nurses(86.59％)and the lowest(48.90％)in medical technicians,HH compliance rates of HCWs of different occupations were statistically significant different(P＜0.001).Among the implementation modes of HH,39.86％used running water for hand washing,42.27％used alcohol-based hand rub to wipe hands,13.22％didn't take HH measures,and 4.65％didn't take HH mea-sures when wearing gloves,with statistically significant differences among different HH implementation modes of HCWs(P＜0.001).There was a positive correlation between the average consumption of HH products per bed·day and HCWs'HH compliance rate(r=0.703,P＜0.05).Conclusion The average consumption of HH products per bed·day and HH compliance rate of HCWs in ICUs in Shanghai presents an increasing trend year by year.There are differences in the average consumption of HH products per bed·day and HH compliance rate among different types of ICUs.The implementation of HH can be evaluated by continuously surveillance on the average consumption of HH products per bed·day.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

Objective To investigate the current situation and health effects of indoor microbial pollution in Xi'an, to analyze the purification effect of air purifiers on indoor microbial pollution, and to provide reference for improving the indoor environment. Methods Through stratified random sampling, 20 families from rural areas and 20 families from upwind and downwind urban areas respectively were selected from Xi'an. Data was collected by questionnaire surveys and on-site environmental sampling. Non-parametric analysis and correlation analysis were used for statistical analysis. Results Overall, the standard-exceeding rate of total count of bacteria was 5.00%. The medians of the total count of bacteria and fungi were 312.50 cfu/m3 and 260.00 cfu/m³, respectively. In terms of health effects, the correlation between rhinitis and cold with total bacterial count was statistically significant (P<0.05), with the correlation coefficients of 0.182 and 0.223, respectively. Purification effect of air purifiers on microbial pollution was statistically significant (P<0.05). After opening for 2 hours, the total numbers of bacteria and fungi decreased significantly. Conclusion The occurrence risk of colds and rhinitis is increased by indoor microbial pollution. Air purifiers have a certain effect on decreasing the total number of bacteria and fungi. It is recommended to use air purifiers with high CADR of particulate matter, double-layer filter and sterilization and dehumidification function, and replace the filters regularly to reduce indoor microbiological contamination.