Aim To investigate the effect of quercetin on the aging model of bone marrow mesenchymal stem cells established under microgravity. Methods Using 3D gyroscope, a aging model of bone marrow mesenchymal stem cells was constructed, and after receiving quercetin and microgravity treatment, the anti-aging effect of the quercetin was evaluated by detecting related proteins and oxidation indexes. Results Compared to the control group, the expressions of age-related proteins p21, pi6, p53 and RB in the microgravity group significantly increased, while the expressions of cyclin D1 and lamin B1 significantly decreased, with statistical significance (P<0.05). In the microgravity group, mitochondrial membrane potential significantly decreased (P<0.05), ROS accumulation significantly increased (P <0.05), SOD content significantly decreased and MDA content significantly increased (P<0.05). Compared to the microgravity group, the expressions of age-related proteins p21, pi6, p53 and RB in the quercetin group significantly decreased, while the expressions of cyclin D1 and lamin B1 significantly increased, with statistical significance (P<0.05). In the quercetin group, mitochondrial membrane potential significantly increased (P<0.05), ROS accumulation significantly decreased (P<0.05), SOD content significantly increased and MDA content significantly decreased (P<0.05). Conclusions Quercetin can resist oxidation, protect mitochondrial function and normal cell cycle, thus delaying the aging of bone marrow mesenchymal stem cells induced by microgravity.

The growth of three plague phages from Qinghai Plateau in two Yersinia pestis strains(plague vaccine strains EV76 and 614F)and four non-Yersinia pestis strains(Yersinia pseudotuberculosis PTB3,PTB5,Escherichia coli V517,and Yersinia enterocolitica 52302-2)were detected through a micromethod based on the OmniLogTM microbial identification system and by the drop method,to provide a scientific basis for future ecological studies and classification based on the host range.For plague vaccine strains EV76 and 614F,successful phage infection and subsequent phage growth were observed in the host bacte-rium.Diminished bacterial growth and respiration and a concomitant decrease in color were observed with the OmniLogTM mi-crobial identification system at 33 ℃ for 48 h.Yersinia pseudotuberculosis PTB5 was sensitive to Yersinia pestis phage 476,but Yersinia pseudotuberculosis PST5 was insensitive to phage 087 and 072204.Three strains of non-Yersinia pestis(Yersinia pseudotuberculosis PTB3,Escherichia coli V517,and Yersinia enterocolitica 52302-2)were insensitive to Yersinia pestis pha-ges 087,072204,and 476 showed similar growth curves.The growth of phages 476 and 087,as determined with the drop method,in two Yersinia pestis strains(plague vaccine strains EV76 and 614F)and four non-Yersinia pestis strains(Yersinia pseudotuberculosis PTB3,Escherichia coli V517,and Yersin-ia enterocolitica 52302-2)showed the same results at 37 ℃,on the basis of comparisons with the OmniLogTM microbial i-dentification system;in contrast,phages 072204 did not show plaques on solid medium at 37 ℃ with plague vaccine strains EV76 and 614F.Determination based on the OmniLogTM detection system can be used as an alternative to the traditional determination of the host range,thus providing favorable application val-ue for determining the interaction between the phage and host bacteria.

Objective To evaluate the anesthetic and postoperative analgesic effects of ultrasound-guided erector spinae plane block(ESPB)with dexmedetomidine combined with ropivacaine in percutaneous endoscopic lumbar discectomy(PELD).Method Patients underwent endoscopic discectomy were randomly divided into local infiltrative anesthesia group(group C),ropivacaine group(group R)and dexmedetomidine combined with ropivacaine group(group DR).Group C received local infiltration anesthesia with 0.375％ropivacaine 20 mL;in group R,the anesthesiologist used 0.375％ropivacaine 20 mL to perform bilateral ESPB.In DR group,0.375％ropivacaine+1 μg·kg-1 dexmedetomidine mixed solution 20 mL was used for bilateral ESPB.The changes of mean arterial pressure(MAP)and heart rate(HR)at 3 min before and after insertion of the channel were observed.The visual analogue scale(VAS)were recorded before operation(T0),at the time of needle positioning(T1),working channel placement(T2),annulus fibrosus operation(T3),at the end of operation(T4),at 4 h(T5),8 h(T6),12 h(T7)and 24 h(T8)after operation were observed.The dosage of intravenous analgesics,vasoactive drugs,and the occurrence of intraoperative adverse drug reactions were observed.Results There were 30 patients in group C,29 patients in group R and 30 patients in group DR.At 3 min after insertion into the channel,HR of group C,group R and group DR were(83.23±5.61),(78.18±4.71)and(77.31±5.13)beat·min-1;MAP were(85.97±3.89),(76.13±4.70)and(74.21±3.12)mmHg;with statistically significant difference(all P＜0.05).The VAS of group C,group R and group DR at T2were(5.80±0.85),(2.38±0.68)and(1.73±0.95)points;at T3 were(4.43±0.57),(2.55±0.57)and(1.63±0.56)points;at T7 were(4.66±0.66),(3.55±0.63)and(3.03±0.66)points;at T8 were(5.53±0.68),(4.07±0.46)and(3.23±0.57)points,all with significant difference(all P＜0.05).The number of additional cases of sufentanil in group C was 17 cases,and in group R was 5 cases,and in group DR was 3 cases,the number of additional cases of sufentanil in group R and DR was significantly less than that in group C(all P＜0.05).There was no significant difference in the incidence of adverse drug reactions among the three groups(all P＞0.05).Conclusion ESPB with dexmedetomidine combined with ropivacaine can significantly reduce intraoperative and postoperative pain,reduce intraoperative opioid use,and has no obvious adverse reactions in patients undergoing PELD.

ObjectiveTemporal heterogeneity in lung cancer presents as fluctuations in the biological characteristics, genomic mutations, proliferation rates, and chemotherapeutic responses of tumor cells over time, posing a significant barrier to effective treatment. The complexity of this temporal variance, coupled with the spatial diversity of lung cancer, presents formidable challenges for research. This article will pave the way for new avenues in lung cancer research, aiding in a deeper understanding of the temporal heterogeneity of lung cancer, thereby enhancing the cure rate for lung cancer. MethodsRaman spectroscopy emerges as a powerful tool for real-time surveillance of biomolecular composition changes in lung cancer at the cellular scale, thus shedding light on the disease’s temporal heterogeneity. In our investigation, we harnessed Raman spectroscopic microscopy alongside multivariate statistical analysis to scrutinize the biomolecular alterations in human lung epithelial cells across various timeframes after benzo(a)pyrene exposure. ResultsOur findings indicated a temporal reduction in nucleic acids, lipids, proteins, and carotenoids, coinciding with a rise in glucose concentration. These patterns suggest that benzo(a)pyrene induces structural damage to the genetic material, accelerates lipid peroxidation, disrupts protein metabolism, curtails carotenoid production, and alters glucose metabolic pathways. Employing Raman spectroscopy enabled us to monitor the biomolecular dynamics within lung cancer cells in a real-time, non-invasive, and non-destructive manner, facilitating the elucidation of pivotal molecular features. ConclusionThis research enhances the comprehension of lung cancer progression and supports the development of personalized therapeutic approaches, which may improve the clinical outcomes for patients.

Objective:To explore the osteogenic activity of in vitro cultured preosteoblasts treated by magnesium loaded hydrogel core-shell microspheres.Methods:A microfluidics chip device was designed and made to fabricate magnesium loaded hydrogel core-shell microspheres to precisely control the stable release of magnesium ions in vitro,the mechanism of controllable magnesium ion release in the promotion of osteogenic activity of MC3T3-E1 preosteoblasts was systematically investigated.Results:The magnesium loaded hydro-gel microspheres(PLGA/MgO-alginate microspheres)prepared by the microfluidics chip exhibited to be monodisperse with special core-shell structure and could control the stable release of magnesium ions at a concentration of 50 ppm in vitro.The in vitro study showed that it significantly enhanced the activity and proliferation ability of MC3T3-E1 preosteoblasts,promoted their osteogenic differ-entiation and mineralization ability,and increased ALP activity.Conclusion:Magnesium loaded hydrogel core-shell microspheres can promote the osteogenic activity of MC3T3-E1 osteoblasts in vitro.

Objective To investigate the distribution of the traditional Chinese medicine(TCM)constitution types in the patients with nonspecific low back pain(NLBP)and to explore the correlation of the thickness of ligamentum flavum with the age,body mass index(BMI),gender,the presence of diabetes mellitus,and the grading of hypertension.Methods Sixty patients with NLBP admitted to Guangdong Second Traditional Chinese Medicine Hospital from January 2023 to June 2023 were selected as the study subjects.The TCM constitution types of the patients were identified,the thickness of the ligamentum flavum at lumbar vertebrae 4/5 segment(L4/5)disc level was measured by computerized tomography(CT)scanning,and the patients'age,genders,TCM constitution types,BMI,the presence or absence of diabetes mellitus,and hypertension grading were recorded.Correlation analysis and linear regression analysis were used for the exploration of the relevant influencing factors for the thickness of the ligamentum flavum of patients with NLBP.Results(1)The average thickness of ligamentum flavum in the 60 patients with NLBP was(2.60±0.72)mm.(2)The TCM constitutions of NLBP patients were classified into four types,of which blood stasis constitution was the most common,accounting for 21 cases(35.0%),followed by 19 cases(31.7%)of damp-heat constitution,12 cases(20.0%)of phlegm-damp constitution,and 8 cases(13.3%)of qi deficiency constitution.(3)The results of correlation analysis showed that BMI,gender,TCM constitution type and the presence or absence of diabetes mellitus had no influence on the thickness of ligamentum flavum in NLBP patients(P＞0.05),while the age and hypertension grading had an influence on the thickness of ligamentum flavum(P＜0.01).(4)The results of linear regression analysis showed that the age had an influence on the thickness of the ligamentum flavum(b = 0.034,t = 6.282,P＜0.01),while the influence of the hypertension grading had no influence on the thickness of the ligamentum flavum(P＞0.05).Conclusion The TCM constitution type of NLBP patients is predominated by blood stasis constitution,the thickness of ligamentum flavum is significantly affected by the age,and hypertension may be a potential factor affecting the thickness of ligamentum flavum.

Objective To observe the clinical efficacy of"triple-posture positive bone-setting"chiropractic manipulation combined with Tongluo Huoxue Formula for the treatment of lumbar spinal stenosis(LSS)with qi deficiency and blood stasis syndrome.Methods Sixty patients with LSS of qi deficiency and blood stasis type were randomly divided into trial group and control group,with 30 cases in each group.The trial group was treated with"triple-posture positive bone-setting"chiropractic manipulation(a chiropractic manipulation performed under the positive cooperation of the patients at three postures)combined with Tongluo Huoxue Formula,while the control group was treated with"triple-posture positive bone-setting"chiropractic manipulation combined with conventional western medicine.The course of treatment for the two groups covered 4 weeks.Before and after treatment,the patients of the two groups were observed in the changes of pain visual analogue scale(VAS)score,Japanese Orthopedic Association(JOA)score of lumbar function,Oswestry Disability Index(ODI)score,straight-leg raising test results and serum interleukin 6(IL-6)and C-reactive protein(CRP)levels.After treatment,the clinical efficacy and safety of the two groups were evaluated.Results(1)After 4 weeks of treatment,the total effective rate of the trial group was 96.67％(29/30)and that of the control group was 63.33％(19/30).The intergroup comparison(tested by Fisher's exact test)showed that the clinical efficacy of the trial group was significantly superior to that of the control group(P＜0.05).(2)After treatment,the lumbar function indicators of pain VAS scores and ODI scores in the trial group were significantly lower(P＜0.05),and the JOA scores were significantly higher than those before treatment(P＜0.05),while in the control group,only the ODI scores were significantly lower than those before treatment(P＜0.05).The intergroup comparison showed that the decrease of VAS and ODI scores and the increase of JOA scores in the trial group were significantly superior to those in the control group(P＜0.05 or P＜0.01).(3)After treatment,the Laseque s sign of the trial group was significantly improved compared with that before treatment(P＜0.05),while no significant improvement was presented in the control group(P＞0.05).The intergroup comparison showed that the improvement of Laseque's sign in the trial group was significantly superior to that in the control group(P＜0.01).(4)After treatment,the levels of serum inflammatory factors of IL-6 and CRP in the two groups were lower than those before treatment(P＜0.05),and the decrease of serum IL-6 level in the trial group was significantly superior to that in the control group(P＜0.05),but CRP level in the two groups after treatment did not differ from that before treatment,no statistically significant difference was shown between the two groups after treatment,either(P＞0.05).(5)The incidence of adverse reactions in the trial group was 6.67％(2/30)and that in the control group was 13.33％(4/30),and the intergroup comparison(by Fisher's exact test)showed that there was no significant difference between the two groups(P＞0.05).Conclusion The therapeutic effect of"triple-posture positive bone-setting"chiropractic manipulation combined with Tongluo Huoxue Formula exert certain effect for the treatment of LSS patients with qi deficiency and blood stasis syndrome,and it has more obvious advantages in improving the lumbar function,promoting the rehabilitation of the patients,and lowering the level of serum inflammatory factors than"triple-posture positive bone-setting"chiropractic manipulation combined with conventional western medication.

The microsphere drug delivery systems have been extensively exploited for providing controllable drug release kinetics, enhancing drug stability and localized drug delivery. In past decade, dozens of microsphere drug delivery systems have been developed for clinical therapy of cancer, schizophrenia and neurodegenerative diseases (e.g., Alzheimer's disease and Parkinsonism). In this review article, we comprehensively summarized the fabrication methods of drug delivery systems and highlighted their advances for clinical application. Furthermore, we analyzed the potential and the challenges for clinical translation of the drug delivery systems.

An analytical method based on ultra high performance liquid chromatography-high resolution tandem mass spectrometry(UHPLC-HRMS/MS)and high performance liquid chromatography-triple quadrupole mass spectrometry(HPLC-TQ MS)was established to reveal the characteristics of various sulfur mustard analogs with different active thiol molecules in CWC Schedule 1.A.04.Firstly,the toxic agents were prepared by micro-directed synthesis,and then the differences of the reactivity and abundance of formed adducts between different sulfur mustards and glutathione(GSH),cysteine(Cys)and N-acetylcysteine(NAC)in incubation solution,plasma and cell were investigated,respectively.The results indicated that all target sulfur mustards could react with three kinds of thiol molecules.The content of Cys and sulfur mustard adducts in plasma was higher than that of GSH and sulfur mustard adducts,while NAC and sulfur mustard adducts might have fewer types of adducts due to low content or poor mass spectrometry response.Additionally,the content of GSH and sulfur mustard adducts in exposed cells was higher than that of Cys,which should be due to the significant difference in the content of thiol molecules in plasma and cells.

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]