Objective:To establish a method for the determination of Mg and Al in 5-layer co-extrusion bags and their migration from the bags into infusion by ICP-MS. Methods:The samples were digested by microwave digestion, and the contents of Mg and Al were determined by ICP-MS under certain working conditions. Results:Both Mg and Al had a linear range between 2. 5 and 20. 0 μg ·L-1, and r was 0. 999 6 and 0. 999 7, respectively. The average recovery of Mg was 92. 90% (RSD=3. 01%,n=9),and that of Al was 94. 15% (RSD=4. 11%,n=9). Conclusion:The method is accurate, sensitive and simple, and can be used for the determi-nation of Mg and Al in 5-layer co-extrusion bags and their migration from the bags into infusion.

ObjectiveTo investigate the effect of sevoflurane preconditioning on heme oxygenase-1 (HO-1) expression in lung tissues during one lung ventilation (OLV) in rats.MethodsTwenty-four male SD rats weighing 220-250 g were randomly divided into 4 groups ( n =6 each):control group (group C) ; two lung ventilation group (group T); OLV group (group O) and sevoflurane preconditioning+ OLV group (group SO).The animals were anesthetized with intraperitoneal pentobarbital sodium 40 mg/kg.In group T,the animals were tracheal intubated and bilateral lungs were ventilated for 1 h (VT 10 ml/kg,RR 60 bpt/min,I∶E 1∶2) and PETCO2 was maintained at 35-50 mm Hg.In groups O and SO,the animals were tracheal intubated and OLV was performed for 1 h (VT 5 ml/kg,RR 80 bpt/min,I:E 1:2) and PETCO2 was maintained at 35-50 mm Hg.In group SO,2.4％sevoflurane was inhaled for 30 min before OLV and then washed out by inhalation of oxygen for 15 min.The left lung tissues were removed in groups C and T,and the bilateral lung tissues were removed in groups.O and SO for microscopic examination and determination of wet/dry lung weight ratio (W/D ratio) and expression of HO-1 (by Western blot).Results Compared with group C,W/D ratio was significantly increased and the expression of HO-1 was up-regulated in left lung tissues in group T and in bilateral lung tissues in groups O and SO ( P ＜0.05).Compared with group T,W/D ratio was significantly increased and the expression of HO-1 was up-regulated in bilateral lung tissues in group O and in right lung tissues in group SO ( P ＜ 0.05).Compared with group O,W/D ratio was significantly decreased,the expression of HO-1 was up-regulated (P ＜ 0.05) and the pathological changes were reduced in bilateral lung tissues in group SO.ConclusionThe mechanism by which sevoflurane preconditioning reduces OLV-induced lung injury is related to up-regulation of HO-1 expression.

Objective To investigate the effect of sevoflurane anesthesia on the cognitive function and phosphorylation of tau in hippocampal neurons in amyloid precursor protein (APP) transgenic mice.Methods Male APP gene mutation mice,weighing 18-22 g,aged 8-12 weeks,were used in the study.Forty-four APP positive mice were randomly divided into 2 groups (n =10 each):sevoflurane group (group AS,n =28) and control group (group AC,n =16).Forty-four APP negative mice were randomly divided into 2 groups:sevoflurane group (group S,n =28) and control group (group C,n =16).Animals in groups S and AS inhaled 3％ sevoflurane for 4 h.While in groups C and AC,animals inhaled pure oxygen for 4 h.Morris water maze was performed 24 h after sevoflurane or pure oxygen inhalation.The phosphorylation of tau at Ser262 and Ser396 was detected by Western blot on 1 day after pure oxygen inhalation (T1) in groups AC and C,and on 1,3 and 7 days after sevoflurane inhalation in groups AS and S.Results Compared with group C,the escape latency was significantly prolonged and the duration of staying at the original platform quadrant was shortened in groups S and AC,and the phosphorylation of tau at Ser262 in group S and phosphorylation of tau at Ser262 and Ser396 in group AS were increased (P ＜0.05).Compared with group S,the escape latency was significantly prolonged,the duration of staying at the original platform quadrant was shortened and the phosphorylation of tau at Ser262 and Ser396 was increased in group AS (P ＜ 0.05).Compared with group AC,the escape latency was significantly prolonged,the duration of staying at the original platform quadrant was shortened and the phosphorylation of tau at Ser262 and Ser396 was increased in group AS (P ＜ 0.05).Conclusion Sevoflurane anesthesia can aggravate the impairment of cognitive function in APP positive mice and the increase in the phosphorylation of tau at Ser262 and Ser396 is involved in the mechanism.

[Objective]To evaluate the role of mature cumulus cells from oocyte-cumulus complex(OCC)in in-vitro maturation(IVM)and establish a new culture technique which is convenient to carry out.[Methods]The cumulus cells of OCC were cut off and dispersed by 1 mL syringe.The cumulus cells were co-cultured with the immature oocytes retrieved from the COH cycles after they adherent to the bottom of the dish.The immature oocytes were experienced IVM procedures in different culture media.They were divided into 3 groups(the oocytes at germinal vesicle stage from one woman were allotted to the same group randomly).Group 1(solution A):basic culture medium+human follicular fluid(hFF);Group 2(solution B):solution A+ cumulus cells(OCC);Group 3(solution C):solution A+ OCC+ follicle stimulating hormone(FSH)+ epidermal growth factor (EGF).Then,the maturation rate,fertilization rate and formation rate of available embryo were observed.[Results]In 113 treatment cycles,298 immature oocytes were performed IVM with solution A,B,and C.The difference for 24 hour maturation rates among 3 groups wag statistically significant(A:45.2%,B:61.7%,C:78.2%,P＜0.05).There was no statistical difference for 25～48 hour maturation rates and normal fertilization rates of mature oocytes.The differences of cleavage rates and rescued embryo rates between group 1 and 2,group 1 and 3 were statistically significant(P＜0.05).The formation rates of available embryo showed an increasing trend from group 1,2,to 3.[Conclusion]After being dispersed by simply beat upon with syringe and adherent culture,the mature cumulus eells from mature OCCs in COH cycles,together with growth factors in the follicular fluid or extraneously supplemented,could promote the IVM of immature oocyte.

BACKGROUND:Twin block appliance has been shown to effectively promote mandibular bone growth of Class Ⅱ malocclusion patients and improve lateral appearance of mandibular retrusion.The other improvement of Twin block appliance on hard-soft tissues remains unclear.OBJECTIVE:To assess the hard-soft tissue changes following Twinblock appliance treatment.METHODS:Atotal of 48 adolescent patients,30 males and 18 females,aged 11.6 years (range 9.58-12.37) with Class Ⅱ malocclusion were selected from Department of Orthodontics,Affiliated Stomatology Hospital of Hebei Medical University.Of them,27 were treated with Twinblock appliance as the treatment group,and 21 adolescent patients without treatments were selected as the control group.Cephalonetric analysis was used to compare the changes before and after treatment.RESULTS AND CONCLUSLON:Comparative analysis showed that Twinblock could effectively adjust or improve the effect of the natural growth,reduced upper lip convexity and mentolabial furrow angle.Moreover,Twinblock inhibited facial vertical distance reduction and facial convexity increase to decrease the potential differences between maxillary and mandibular bones in sagittal plance.Results show that Twinblock could effectively improve the profile of soft-tissues of Class Ⅱ malocclusion cases,

Objective To investigate the effect of fructose-1,6-diphosphate (FDP) pretreatment on myocardial connexin43 (Cx43) in a rat model of acute myocardial ischemia.Methods Thirty-six male 8-12 week old SD rata weighing 220-280 g were randomly divided into 3 groups (n=12 each):group Ⅰ sham operation (group S);group Ⅱ ischemia(group Ⅰ)and group Ⅲ FDP+ischemia(group F).The animals were anesthetized with intraperitoneal 10%chloral hydrate 40 mg/100 g,tracheostomized and mechanically ventilated.Acute myocardial ischemia was induced by occlusion of left anterior descending coronary artery for 30 min.Myocardial ischemia was;verified by elevation of S-T segment on ECG.In group F FDP 100 mg/kg was injected iv at 10 min before ischemia.Arrhythmia was recorded within 30 min after occlusion and the severity of arrbythmia was aggesged.The hearts were removed after 30 min myocardial ischemia.The Left ventricle area (LVA),myocardial infarct area (IA) and area at risk (AAR) were measured and AAR/LVA and IA/AAR ratios were calculated.The expression of myocardial Cx43 protein was determined by immuno-histochemestry and analysis of mean optical density.Results The severity of arrhythmia was significantly higher in group F and I than in gropu S.while lower in group F than in group I(P<0.05).The IA,IA/AAR ratio was significantly lower in group F than in group I.The myocardial Cx43 protein expression was down-regulated in group I and F as compared with group S.and was significantly lower in group I than in group F.Conclusion FDP pretreatment can protect myocardium against acute ischemia by up-regulation of myocardial Cx43 expression.

Objective:To observe the effects of acupuncture at Houxi(SI3)and Huantiao(GB30)on the expression levels of nuclear factor kappa B(NF-κB),inducible nitric oxide synthase(iNOS),and nitric oxide(NO)of NF-κB inflammatory signaling pathway in L5 spinal nerve root of lumbar disc herniation(LDH)model rats and explore the mechanism of acupuncture in LDH treatment.Methods:Forty specific-pathogen-free healthy male Sprague-Dawley rats were randomly divided into a sham operation group,a model group,acupuncture group 1,and acupuncture group 2,with 10 rats in each group.The non-compression nucleus protrusion model was made by puncturing L4-L5 spinous process space and injecting autologous nucleus suspension.Acupuncture at bilateral Shenshu(BL23),Dachangshu(BL25),and Weizhong(BL40)was carried out in acupuncture group 1,and acupuncture at bilateral Houxi(SI3)and Huantiao(GB30)in acupuncture group 2.All rats were treated with balanced reinforcing and reducing needling manipulations,and the needles were retained for 30 min/time with one episode of needling manipulation every 10 min,once a day,14 times in total.The threshold value of paw withdrawal pain was measured by a thermal stimulation pain instrument;the serum NF-κB,iNOS,and NO levels were measured by enzyme-linked immunosorbent assay.The pathomorphological changes of spinal nerve roots were observed by hematoxylin-eosin(HE)staining;quantitative reverse transcription polymerase chain reaction was used to detect iNOS mRNA expression in spinal nerve roots;the NF-κB and iNOS protein expression in spinal nerve roots was detected by the immunofluorescence method.Results:Compared with the sham operation group,the threshold of paw withdrawal pain in the model group was decreased,and the expression levels of serum NF-κB,iNOS,and NO were increased;HE staining showed many degenerated and dissolved Schwann cells in spinal nerve roots with vacuolar changes;meanwhile,the expression levels of NF-κB and iNOS proteins,and the iNOS mRNA in spinal nerve roots were increased.Compared with the model group,the paw withdrawal pain thresholds in acupuncture group 1 and acupuncture group 2 were increased,and the increase in acupuncture group 2 was greater(P<0.05);the expression levels of serum NF-κB,iNOS,and NO in acupuncture group 1 and acupuncture group 2 were decreased,especially in acupuncture group 2(P<0.01);the vacuolar changes of spinal nerve roots,and the degeneration and lysis of Schwann cells in acupuncture group 1 and acupuncture group 2 were decreased,which were more obvious in acupuncture group 2;the NF-κB and iNOS protein expression and the iNOS mRNA expression levels in spinal nerve roots of acupuncture group 1 and acupuncture group 2 were decreased,especially in acupuncture group 2(P<0.01).Conclusion:Acupuncture at Houxi(SI3)and Huantiao(GB30)can improve the morphology of spinal nerve roots,inhibit the NF-κB and iNOS protein expression levels in spinal nerve roots and the serum NO level,and relieve the pain caused by inflammation of spinal nerve roots,which may be one of the mechanisms of acupuncture in LDH treatment.

Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

Objective To understand the distribution and changing resistance profiles of clinical isolates of Enterococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Enterococcus according to the unified protocol of CHINET program by automated systems,Kirby-Bauer method,or E-test strip.The results were interpreted according to the Clinical & Laboratory Standards Institute(CLSI)breakpoints in 2021.WHONET 5.6 software was used for statistical analysis.Results A total of 124 565 strains of Enterococcus were isolated during the 7-year period,mainly including Enterococcus faecalis(50.7％)and Enterococcus faecalis(41.5％).The strains were mainly isolated from urinary tract specimens(46.9％±2.6％),and primarily from the patients in the department of internal medicine,surgery and ICU.E.faecium and E.faecalis strains showed low level resistance rate to vancomycin,teicoplanin and linezolid(≤3.6％).The prevalence of vancomycin-resistant E.faecalis and E.faecium was 0.1％and 1.3％,respectively.The prevalence of linezolid-resistant E.faecalis increased from 0.7％in 2015 to 3.4％in 2021,while the prevalence of linezolid-resistant E.faecium was 0.3％.Conclusions The clinical isolates of Enterococcus were still highly susceptible to vancomycin,teicoplanin,and linezolid,evidenced by a low resistance rate.However,the prevalence of linezolid-resistant E.faecalis was increasing during the 7-year period.It is necessary to strengthen antimicrobial resistance surveillance to effectively identify the emergence of antibiotic-resistant bacteria and curb the spread of resistant pathogens.

Objective To examine the changing antimicrobial resistance profile of Enterobacter spp.isolates in 53 hospitals across China from 2015 t0 2021.Methods The clinical isolates of Enterobacter spp.were collected from 53 hospitals across China during 2015-2021 and tested for antimicrobial susceptibility using Kirby-Bauer method or automated testing systems according to the CHINET unified protocol.The results were interpreted according to the breakpoints issued by the Clinical & Laboratory Standards Institute(CLSI)in 2021(M100 31st edition)and analyzed with WHONET 5.6 software.Results A total of 37 966 Enterobacter strains were isolated from 2015 to 2021.The proportion of Enterobacter isolates among all clinical isolates showed a fluctuating trend over the 7-year period,overall 2.5％in all clinical isolates amd 5.7％in Enterobacterale strains.The most frequently isolated Enterobacter species was Enterobacter cloacae,accounting for 93.7％(35 571/37 966).The strains were mainly isolated from respiratory specimens(44.4±4.6)％,followed by secretions/pus(16.4±2.3)％and urine(16.0±0.9)％.The strains from respiratory samples decreased slightly,while those from sterile body fluids increased over the 7-year period.The Enterobacter strains were mainly isolated from inpatients(92.9％),and only(7.1±0.8)％of the strains were isolated from outpatients and emergency patients.The patients in surgical wards contributed the highest number of isolates(24.4±2.9)％compared to the inpatients in any other departement.Overall,≤ 7.9％of the E.cloacae strains were resistant to amikacin,tigecycline,polymyxin B,imipenem or meropenem,while ≤5.6％of the Enterobacter asburiae strains were resistant to these antimicrobial agents.E.asburiae showed higher resistance rate to polymyxin B than E.cloacae(19.7％vs 3.9％).Overall,≤8.1％of the Enterobacter gergoviae strains were resistant to tigecycline,amikacin,meropenem,or imipenem,while 10.5％of these strains were resistant to polycolistin B.The overall prevalence of carbapenem-resistant Enterobacter was 10.0％over the 7-year period,but showing an upward trend.The resistance profiles of Enterobacter isolates varied with the department from which they were isolated and whether the patient is an adult or a child.The prevalence of carbapenem-resistant E.cloacae was the highest in the E.cloacae isolates from ICU patients.Conclusions The results of the CHINET Antimicrobial Resistance Surveillance Program indicate that the proportion of Enterobacter strains in all clinical isolates fluctuates slightly over the 7-year period from 2015 to 2021.The Enterobacter strains showed increasing resistance to multiple antimicrobial drugs,especially carbapenems over the 7-year period.