ObjectiveTo explore the effect of timosaponin BⅡ （TBⅡ） combined with icariin （ICA） on osteoclast （OC）-osteoblast （OB） coupling and decipher the mechanism from the cellular level. MethodsThe cell counting kit-8 （CCK-8） was used to assess the effects of different concentrations of TBⅡ and different concentrations of TBⅡ+ICA on the growth of RAW264.7 cells. Soluble receptor activator of nuclear factor-κB ligand （sRANKL） was used to induce the differentiation of RAW264.7 pre-osteoclasts into osteoclasts. The cells were allocated into sRANKL， TBⅡ （1， 5， 10 μmol·L^-1）， and TBⅡ+ICA groups. Tartrate-resistant acid phosphatase staining was performed to assess the effects of TBⅡ and TBⅡ+ICA on osteoclast differentiation. Real-time quantitative polymerase chain reaction （Real-time PCR） was conducted to examine the effects of TBⅡ+ICA on the expression of key genes involved in osteoclast differentiation and osteoclast-derived coupling factors. The osteogenic differentiation conditioned medium mixed with osteoclast supernatant was used to induce osteogenic differentiation of MC3T3-E1 cells. Alkaline phosphatase staining and alizarin red S staining were employed to determine the effect of TBⅡ+ICA on osteogenic differentiation. Real-time PCR was employed to evaluate the effects of conditioned medium on key genes involved in osteogenic differentiation. ResultsTBⅡ at 1， 5， 10 μmol·L^-1 had no significant effect on the cell survival rate. Compared with the sRANKL group， TBⅡ inhibited osteoclast differentiation in a dose-dependent manner and achieved the best effect at 10 μmol·L^-1 （P<0.01）. Compared with the sRANKL group， different concentrations of TBⅡ down-regulated the mRNA levels of osteoclast differentiation-related genes c-Fos， RANK， and RANKL （P<0.05）. None of 10 μmol·L^-1 TBⅡ， 10 μmol·L^-1 TBⅡ+10^-4 μmol·L^-1 ICA， or 10 μmol·L^-1 TBⅡ+10^-3 μmol·L^-1 ICA affected the viability of RAW264.7 cells. TBⅡ and/or ICA inhibited osteoclast differentiation （P<0.01）， and TBⅡ + ICA had the best effect （P<0.01）. Compared with the sRANKL group， TBⅡ and/or ICA down-regulated the mRNA levels of c-Fos， RANK， and RANKL （P<0.05）. The single application of TBⅡ and ICA had no significant effect on the mRNA levels of Wnt10b， Cthrc1， and C3a， while TBⅡ+ICA exerted up-regulating effects （P<0.05）. Compared with those in the blank group， the bone differentiation and mineralization abilities of the normal osteogenic induction group and each osteogenic induction + osteoclast supernatant group were improved （P<0.01）. Compared with the blank group， the normal osteogenic induction group and the osteogenic induction + osteoclast supernatant group showed up-regulated mRNA levels of Runx2 and OCN （P<0.01）. ConclusionTBⅡ+ICA can inhibit osteoclast differentiation， maintain the normal osteoclast-osteoblast coupling， and promote osteogenic differentiation.

Currently, the drug delivery system (DDS) based on nanomaterials has become a hot interdisciplinary research topic. One of the core issues is drug loading and controlled release, in which the key lever is carriers. Vaterite, as an inorganic porous nano-material, is one metastable structure of calcium carbonate, full of micro or nano porous. Recently, vaterite has attracted more and more attention, due to its significant advantages, such as rich resources, easy preparations, low cost, simple loading procedures, good biocompatibility and many other good points. Vaterite, gained from suitable preparation strategies, can not only possess the good drug carrying performance, like high loading capacity and stable loading efficiency, but also improve the drug release ability, showing the better drug delivery effects, such as targeting release, pH sensitive release, photothermal controlled release, magnetic assistant release, optothermal controlled release. At the same time, the vaterite carriers, with good safety itself, can protect proteins, enzymes, or other drugs from degradation or inactivation, help imaging or visualization with loading fluorescent drugs in vitro and in vivo, and play synergistic effects with other therapy approaches, like photodynamic therapy, sonodynamic therapy, and thermochemotherapy. Latterly, some renewed reports in drug loading and controlled release have led to their widespread applications in diverse fields, from cell level to clinical studies. This review introduces the basic characteristics of vaterite and briefly summarizes its research history, followed by synthesis strategies. We subsequently highlight recent developments in drug loading and controlled release, with an emphasis on the advantages, quantity capacity, and comparations. Furthermore, new opportunities for using vaterite in cell level and animal level are detailed. Finally, the possible problems and development trends are discussed.

Objective To develop a time-resolved fluorescent immunoassay kit for the rapid,accurate and quantitative detection of S100B protein in serum and to evaluate its performance.Methods The test strip was prepared using time-resolved fluorescent microsphere-labeled anti-S100B polyclonal antibody and rabbit IgG antibody,labeling pads,sample pads,S100B nitrocellulose films and absorbent paper,and an S100B time-resolved fluorescence immunoassay kit was obtained by assembling the cartridge.The performance of the kit developed was evaluated by standard curve,accuracy,minimum detection limit,linear interval,specificity,reproducibility and stability.The reference intervals of 199 pieces of healthy human serum and plasma samples from a certain region were detected with the kit,and the clinical performance of the kit and Roche Elecsys S100 kit was tested by synchronous blind method to assess the consistency of the results of the two kits for 142 samples.Results The S100B time-resolved fluorescence immunoassay kit had the standard curve beingy=(1.133 02+1.752 24)/[1+(x/1.082 20)×(-0.603 52)]-1.752 24,R2=0.999 08 and the linear range being[0.05,30]ng/mL,which met the requirements of the relative deviation of the accuracy within±15％,the minimum detection limit not hgier than 0.05 ng/mL,the relative deviation of specificity within±15％and the coefficient of variation of intra-and inter-batch difference less than 15％.The stability test results indicated that the kit was valid for 12 months at 2-30 ℃ conditions.The reference intervals of serum and plasma samples measured by the kit were both lower than 0.3 ng/mL.Clinical trials showed that the results by the kit and Roche Elecsys S100 Assay Kit were in high agreement(Kappa=0.906 1＞0.80)and met the requirements.Conclusion The kit developed detects the concentration of S100B protein in serum quickly,accurately and quantitatively,and provides references for the diagnosis and treatment of neurological diseases,autoimmune diseases,cerebrovascular diseases and etc.[Chinese Medical Equipment Journal,2024,45(1):47-55]

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.

AIM To evaluate the quality of Beidougen Formula Granules.METHODS Fifteen batches of standard decoctions and three batches of formula granules were prepared,after which paste rate and contents,transfer rates of magnoflorine,daurisoline,dauricine were determined.HPLC specific chromatograms were established,and cluster analysis was adopted in chemical pattern recognition.RESULTS For three batches of formula granules,the paste rates were 15.1%-16.6%,the contents of magnoflorine,daurisoline,dauricine were 18.93-19.39,9.42-9.60,6.79-6.85 mg/g with the transfer rates of 34.42%-35.25%,43.81%-44.65%,27.27%-27.51%from decoction pieces to formula granules,respectively,and there were seven characteristic peaks in the specific chromatograms with the similarities of more than 0.95,which demonstrated good consistence with those of standard decoctions and accorded with related limit requirements.Fifteen batches of standard decoctions were clustered into two types,and the medicinal materials produced from Jilin,Hebei,Shangdong could be used for the preparation of formula granules.CONCLUSION This reasonable and reliable method can provide references for the quality control and clinical application of Beidougen Formula Granules.

BACKGROUND:Multiple sclerosis is a chronic inflammatory demyelinating disease of the central nervous system mediated by T cells.The Toll-like receptors(TLRs)/myeloid differentiation factor 88(MyD88)/nuclear factor kappa-B(NF-κB)signaling pathway plays an important role in the development of the disease.Exploring the specific mechanism of the signaling pathway is essential for further treatment of the disease and improving the prognosis of patients. OBJECTIVE:To review the TLRs/MyD88/NF-κB signaling pathway and its role in multiple sclerosis/experimental autoimmune encephalomyelitis models,which provides new ideas and strategies for the treatment of multiple sclerosis by inhibiting the TLRs/MyD88/NF-κB signaling pathway. METHODS:The literature related to the topic from January 2002 to December 2022 was searched in CNKI,WanFang and PubMed databases.A total of 61 articles were finally included for analysis. RESULTS AND CONCLUSION:The TLRs/MyD88/NF-κB signaling pathway is an important pathway that triggers a pro-inflammatory immune response.The TLRs/MyD88/NF-κB signaling pathway plays an important role in the development of multiple sclerosis by regulating the antigen presentation of dendritic cells,destroying the integrity of the blood-brain barrier,and promoting the activation of T cells,B cells and microglia.By targeting TLRs,MyD88 and NF-κB molecules,inhibiting the activation or signal transduction of TLRs,MyD88 and NF-κB,and reducing the secretion of pro-inflammatory factors,multiple sclerosis can be treated.Animal studies have shown that active ingredients of traditional Chinese medicines,such as flavonoids and glycosides,and traditional Chinese medicine compound formulas,such as Buyang Huanwu Tang,can also treat experimental autoimmune encephalomyelitis by regulating the TLRs/MyD88/NF-κB signaling pathway,which points to the direction of searching for medicines targeting the TLRs/MyD88/NF-κB signaling pathway for the treatment of multiple sclerosis.

Objective To observe the incidence of pericardial tamponade(PT)after left atrial appendage closure(LAAC)in patients with non-valvular atrial fibrillation(NVAF),and to explore its related factors and outcomes.Methods NVAF patients who were hospitalized and treated with LAAC in Department of Cardiology of our hospital from August 2014 to March 2023 were selected for the study.The general clinical data,preoperative transthoracic echocardiography and transesophageal echocardiography data,results of routine preoperative laboratory tests,intraoperative data and follow-up data of the patients were collected through the hospital medical record management system.The enrolled patients were classified into the non-PT group(n=8)and the PT group(n =1184)according to whether PT occurred after LAAC or not.The incidence of PT,related risk factors and outcomes were statistically analyzed.Results This study included 639 males(53.6%)and 553 females(46.4%),with an average age of 68.1±9.65 years.The CHA2 DS2-VASc score was 4.51±1.72,and the HAS-BLED score was 3.36±1.09.PT occurred in 8 cases(0.67%),among them,6 cases occurred 1 to 33 h after LAAC,and 2 cases occurred on day 19 and day 27 after LAAC.As for the results of transesophageal echocardiography(TEE)and LAA angiography,compared with the non-PT group,the PT group had the significantly larger maximum caliber of the LAA(P=0.025,P=0.015),smaller maximum depth of the LAA(P=0.028,P=0.031),and lower success rate of one-time placement of the occluder(P=0.031);The occluder compression rate of the PT group was significantly greater than that of the non-PT group(P=0.046).Multivariate analysis showed that larger maximum diameter of LAA,smaller average effective depth of LAA and larger compression rate of occluder were the main risk factors for PT.All the 8 PT patients were cured by stopping antithrombotic drugs,pericardiocentesis or surgical drainage.During a mean follow-up of 39±27 months,there were no device-related thrombosis(DRT),ischemic stroke,systemic embolism and other complications in the PT group.Conclusion The incidence of PT after LAAC is low,which is related to the large diameter of LAA,the relatively insufficient depth of the LAA and the large compression rate of the occlude.PT can be cured by stopping antithrombotic drugs and pericardiocentesis/surgical drainage.

Objective This study aimed to compare the current Essen rabies post-exposure immunization schedule(0-3-7-14-28)in China and the simple 4-dose schedule(0-3-7-14)newly recommended by the World Health Organization in terms of their safety,efficacy,and protection. Methods Mice were vaccinated according to different immunization schedules,and blood was collected for detection of rabies virus neutralizing antibodies(RVNAs)on days 14,21,28,35,and 120 after the first immunization.Additionally,different groups of mice were injected with lethal doses of the CVS-11 virus on day 0,subjected to different rabies immunization schedules,and assessed for morbidity and death status.In a clinical trial,185 rabies-exposed individuals were selected for post-exposure vaccination according to the Essen schedule,and blood was collected for RVNAs detection on days 28 and 42 after the first immunization. Results A statistically significant difference in RVNAs between mice in the Essen and 0-3-7-14 schedule groups was observed on the 35th day(P<0.05).The groups 0-3-7-14,0-3-7-21,and 0-3-7-28 showed no statistically significant difference(P>0.05)in RVNAs levels at any time point.The post-exposure immune protective test showed that the survival rate of mice in the control group was 20%,whereas that in the immunization groups was 40%.In the clinical trial,the RVNAs positive conversion rates on days 28(14 days after 4 doses)and 42(14 days after 5 doses)were both 100%,and no significant difference in RVNAs levels was observed(P>0.05). Conclusion The simple 4-dose schedule can produce sufficient RVNAs levels,with no significant effect of a delayed fourth vaccine dose(14-28 d)on the immunization potential.

Objective:To investigate the application effect of 3D printed fetal heart model based on ultrasound data combined with case-based learning (CBL) in prenatal ultrasound teaching of complex heart malformations in standardized residency training of ultrasound medicine.Methods:A total of 60 students majoring in ultrasound imaging who received standardized residency training in Ultrasonography Center of Obstetrics and Gynecology, Renmin Hospital of Wuhan University, from September 2020 to August 2022 were enrolled as subjects and divided into experimental group and control group, with 30 students in each group. The students in the experimental group received teaching with 3D printed fetal heart model and CBL teaching, and those in the control group received teaching with hand-painted heart diagram and CBL teaching. The two groups were compared in terms of the score of theoretical examination, the degree of satisfaction with teaching, and the self-rated score of the understanding of each disease before and after teaching, and the correlation of the increase in score with case complexity was also analyzed. MedCalc software was used to perform the t-test and the linear regression analysis. Results:The experimental group had a significantly higher score of theoretical examination than the control group [(85.70±8.70) vs. (71.40±9.50)]. The questionnaire survey showed that the experimental group had better feedbacks than the control group in the aspects such as the degree of satisfaction with teaching ( P<0.05). After the implementation of this teaching model, compared with the control group, the experimental group had significantly higher self-rated scores of the understanding of case 2, case 3, case 4, and case 5 ( P<0.05). The increase in score after teaching was positively correlated with the complexity score of abnormal cases ( R2=0.90, P=0.010; R2=0.94, P=0.010), and the experimental group tended to have a greater regression coefficient. Conclusions:The reasonable application of 3D printed fetal heart model combined with CBL teaching in fetal heart teaching in standardized residency training of ultrasound medicine can help the students to understand and enhance the knowledge of cardiac anatomy, improve the learning experience of fetal echocardiography, and deepen the understanding and awareness of complex congenital heart disease.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]