OBJECTIVE To observe the isolation rates and drug resistance rates of Acinetobacter baumannii strains isolated from intensive care unit(ICU)patients in 8 consecutive years so as to provide bases for reasonable clinical application of antibiotics and control of infections.METHODS The isolation rates and specimens from which the A.baumannii and carbapenem-resistant A.baumannii(CRAB)strains were isolated from ICU patients of the First People's Hospital of Changzhou between 2017 and 2024 were retrospectively analyzed.The trends of the drug resistance rates were observed.RESULTS Totally 2078(18.03％)strains of A.baumannii were isolated from the ICU patients from 2017 to 2024,and there was no significant difference in the changing trend among the years(x2=-1.573,P=0.116).Among the A.baumannii strains that were isolated from 2017 to 2024,58.08％were isolated from sputum,and 24.25％from lavage fluid specimens;the percentage of sputum specimens showed a downward trend in the 8 years(x2=-8.257,P＜0.001),while the percentage of lavage fluid speci-mens showed an upward trend(x2=12.964,P＜0.001).The isolation rate of the CRAB strains was 91.48％in 2017,92.61％in 2018,92.56％in 2019,82.53％in 2020,52.44％in 2021,showing a down-ward trend,and it began to rise in 2022-2024,there was significant difference(x2=-2.277,P=0.012).The isolation rates of the CRAB strains from both sputum and lavage fluid specimens showed downward trends and then upward trends(all P＜0.05).The drug resistance rates of the A.baumannii strains to piperacillin and minocycline showed slow upward trends,while the drug resistance rates to gentamicin and tigecycline showed downward trends,and there were significant differences(P＜0.05).The drug resistance rates of the A.bau-mannii strains to imipenem and meropenem remained more than 90％.CONCLUSIONS Acinetobacter spp is the major pathogen causing the hospital-acquired infection.The isolation rate of CRAB strains shows a downward trend then a upward trend in recent two years.It is necessary for the hospital to standardize the submission of spu-tum specimens and increase the aseptic submission.The A.baumannii strains show high drug resistance rates to the commonly used antibiotics.Polymyxin B,tigecycline and minocycline are the major antibiotics for treatment of CRAB infection.

Objective To investigate the effect and mechanism of melatonin in alleviating hypoxia-induced apoptosis in ovarian gra-nulosa cells.Methods Rat ovarian granulosa cells were isolated and divided into normoxic,hypoxic,and melatonin groups.Hypoxia-induced injury models were established in the hypoxic and melatonin groups,and granulosa cells in the melatonin group were treated with melatonin.A total of 24 rats were randomized into the control,model,and intervention groups(n=8 per group).Rat models of declining ovarian function induced by long-term hypoxia were established in the model and intervention groups.The rats in the intervention group were intraperitoneally injected with melatonin.Cell proliferation was measured using a CCK-8 assay,and lactate secretion and HIF-1αprotein with a specific kit,respectively.The levels of estradiol and progesterone in the cell supernatant and rat serum were detected using ELISA.Granulosa cell apoptosis was detected by flow cytometry,ovarian morphology by HE staining,and Bax and caspase-3 expression by Western blotting.Results Compared with the normoxic group,the hypoxic group exhibited decreased granulosa cell proliferation,increased apoptosis,elevated lactate and HIF-1α levels,and reduced estradiol and progesterone levels(P＜0.05).Compared with hypoxic group,these changes were significantly reversed in the molatonin group(P＜0.05).Compared with the control group,the model group showed increased lactate,HIF-1α,Bax,and caspase-3 levels,decreased estradiol and progesterone levels,and reduced follicles.Compared with the model group,all the indicators were ameliorated in the intervention group(P＜0.05).Conclusion Melatonin alleviated hypoxia-induced granulosa cell apoptosis and promoted the recovery of ovarian function.

Objective To explore the differences and similarities in the changes of pulp repair response after direct pulp capping with iRoot BP Plus and MTA.Methods A total of 36 male SD rats were randomly divided into 3 groups,namely iRoot BP Plus group,MTA group and blank control group.Dental pulp exposure and direct pulp capping was performed on both sides of maxillary first molars of each rat.Four rats were randomly selected and sacrificed from each group at 7,14,and 28 days postoperatively,and the specimens were taken for hematoxylin-eosin(HE)staining,and then each index was observed.Results ①From the perspective of dentin tubular formation quality,at 14 d and 28 d,there were statistical differences between iRoot BP Plus group and MTA group(P＜0.05),and iRoot BP Plus was significantly better than MTA in terms of quality of restorative dentin formation.②At 14 days after operation,iRoot BP Plus had a greater area of neodontinin than that in MTA group(P＜0.05).Conclusion Both iRoot BP Plus and MTA can promote the formation of restorative dentin bridges after direct pulp capping,and the formation quality is high.The long-term effects need to be further studied.

OBJECTIVE To observe the isolation rates and drug resistance rates of Acinetobacter baumannii strains isolated from intensive care unit(ICU)patients in 8 consecutive years so as to provide bases for reasonable clinical application of antibiotics and control of infections.METHODS The isolation rates and specimens from which the A.baumannii and carbapenem-resistant A.baumannii(CRAB)strains were isolated from ICU patients of the First People's Hospital of Changzhou between 2017 and 2024 were retrospectively analyzed.The trends of the drug resistance rates were observed.RESULTS Totally 2078(18.03％)strains of A.baumannii were isolated from the ICU patients from 2017 to 2024,and there was no significant difference in the changing trend among the years(x2=-1.573,P=0.116).Among the A.baumannii strains that were isolated from 2017 to 2024,58.08％were isolated from sputum,and 24.25％from lavage fluid specimens;the percentage of sputum specimens showed a downward trend in the 8 years(x2=-8.257,P＜0.001),while the percentage of lavage fluid speci-mens showed an upward trend(x2=12.964,P＜0.001).The isolation rate of the CRAB strains was 91.48％in 2017,92.61％in 2018,92.56％in 2019,82.53％in 2020,52.44％in 2021,showing a down-ward trend,and it began to rise in 2022-2024,there was significant difference(x2=-2.277,P=0.012).The isolation rates of the CRAB strains from both sputum and lavage fluid specimens showed downward trends and then upward trends(all P＜0.05).The drug resistance rates of the A.baumannii strains to piperacillin and minocycline showed slow upward trends,while the drug resistance rates to gentamicin and tigecycline showed downward trends,and there were significant differences(P＜0.05).The drug resistance rates of the A.bau-mannii strains to imipenem and meropenem remained more than 90％.CONCLUSIONS Acinetobacter spp is the major pathogen causing the hospital-acquired infection.The isolation rate of CRAB strains shows a downward trend then a upward trend in recent two years.It is necessary for the hospital to standardize the submission of spu-tum specimens and increase the aseptic submission.The A.baumannii strains show high drug resistance rates to the commonly used antibiotics.Polymyxin B,tigecycline and minocycline are the major antibiotics for treatment of CRAB infection.

Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.

Objective To explore the differences and similarities in the changes of pulp repair response after direct pulp capping with iRoot BP Plus and MTA.Methods A total of 36 male SD rats were randomly divided into 3 groups,namely iRoot BP Plus group,MTA group and blank control group.Dental pulp exposure and direct pulp capping was performed on both sides of maxillary first molars of each rat.Four rats were randomly selected and sacrificed from each group at 7,14,and 28 days postoperatively,and the specimens were taken for hematoxylin-eosin(HE)staining,and then each index was observed.Results ①From the perspective of dentin tubular formation quality,at 14 d and 28 d,there were statistical differences between iRoot BP Plus group and MTA group(P＜0.05),and iRoot BP Plus was significantly better than MTA in terms of quality of restorative dentin formation.②At 14 days after operation,iRoot BP Plus had a greater area of neodontinin than that in MTA group(P＜0.05).Conclusion Both iRoot BP Plus and MTA can promote the formation of restorative dentin bridges after direct pulp capping,and the formation quality is high.The long-term effects need to be further studied.

Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.

Objective To investigate the effect and mechanism of melatonin in alleviating hypoxia-induced apoptosis in ovarian gra-nulosa cells.Methods Rat ovarian granulosa cells were isolated and divided into normoxic,hypoxic,and melatonin groups.Hypoxia-induced injury models were established in the hypoxic and melatonin groups,and granulosa cells in the melatonin group were treated with melatonin.A total of 24 rats were randomized into the control,model,and intervention groups(n=8 per group).Rat models of declining ovarian function induced by long-term hypoxia were established in the model and intervention groups.The rats in the intervention group were intraperitoneally injected with melatonin.Cell proliferation was measured using a CCK-8 assay,and lactate secretion and HIF-1αprotein with a specific kit,respectively.The levels of estradiol and progesterone in the cell supernatant and rat serum were detected using ELISA.Granulosa cell apoptosis was detected by flow cytometry,ovarian morphology by HE staining,and Bax and caspase-3 expression by Western blotting.Results Compared with the normoxic group,the hypoxic group exhibited decreased granulosa cell proliferation,increased apoptosis,elevated lactate and HIF-1α levels,and reduced estradiol and progesterone levels(P＜0.05).Compared with hypoxic group,these changes were significantly reversed in the molatonin group(P＜0.05).Compared with the control group,the model group showed increased lactate,HIF-1α,Bax,and caspase-3 levels,decreased estradiol and progesterone levels,and reduced follicles.Compared with the model group,all the indicators were ameliorated in the intervention group(P＜0.05).Conclusion Melatonin alleviated hypoxia-induced granulosa cell apoptosis and promoted the recovery of ovarian function.

Objective To understand the economic losses due to healthcare-associated infection(HAI)in patients after Da Vinci robotic thoracic surgery,and provide basis for preventing and controlling HAI after robotic surgery.Methods Patients who underwent Da Vinci robotic surgery from April 2019 to April 2023 were retrospective stu-died.Patients were divided into HAI group and non-HAI group based on the occurrence of postoperative infection.Through 1∶1 propensity score matching(PSM),31 cases were included in each group,economic losses of two groups of patients were compared.Results A total of 921 patients who underwent Da Vinci robotic thoracic surgery were included in the study,51 cases with HAI(HAI group)and 870 without HAI(non-HAI group).After 1∶1 PSM,31 cases were included in each group.Four covariates were compared between two groups of patients before PSM,namely gender,age,comorbidities,and the American Society of Anesthesiologists(ASA)grading,all with statistically significant differences(all P＜0.05).After PSM,distribution of the above covariates reached equilib-rium between the two groups(both P＞0.05).The median total expense for HAI group before PSM during hospi-talization was 88 711.72 Yuan,while 78 509.46 Yuan for the non-HAI group.The direct economic losses caused by HAI after Da Vinci robot surgery was 10 202.26 Yuan,mainly increased by expense of medicine,nursing,laborato-ry diagnosis,etc.Difference in western medicine expense was the highest(8 839.12 Yuan),out of which expense of antimicrobial agents accounted for the highest proportion(73.55％).Difference in daily hospitalization expense between HAI-group and non-HAI group was 502.38 Yuan.Length of hospital stay of patients in HAI group and non-HAI group were(21.59±10.62)and(13.92±9.21)days,respectively,with statistical differences(all P＜0.05).Conclusion The occurrence of HAI in patients undergoing Da Vinci robotic thoracic surgery leads to direct economic losses,with obvious increases in expenses of nursing,laboratory diagnosis,western medicine(mainly an-timicrobial agents).Length of hospital stay of patients also prolongs.

Objective:To investigate the clinical experience and efficacy of unrelated umbilical cord blood hematopoietic stem cell transplantation (HSCT) for the treatment of congenital amegakaryocytic thrombocytopenia (CAMT).Methods:A case summary was conducted.The clinical data of 2 children with CAMT who were finally cured by unrelated umbilical cord blood HSCT in the Department of Pediatric Medicine, the First Affiliated Hospital of Zhengzhou University from March 2020 to August 2023 were retrospectively analyzed.Related studies were retrieved from databases CNKI, Wanfang and PubMed using search terms including " congenital amegakaryocytic thrombocytopenia" and " hematopoietic stem cell transplantation" from the inception to July 2024.The clinical characteristics, diagnosis and treatment processes, and prognosis of CAMT patients treated by HSCT were then summarized.Results:Both cases exhibited scattered skin haemorrhages throughout the body and carried 2 compound heterozygous mutations with pathogenicity in the MPL gene.Both patients were finally diagnosed with CAMT.Case 1 was a girl aged 3 at the time of transplantation, and case 2 was also a girl, who aged 5 at the time of transplantation.Both of them received unrelated umbilical cord blood HSCT and hematopoietic reconstruction was achieved.The time of neutrophil and platelet implantation was 21 and 40 days after transplantation in case 1, and 20 and 31 days in case 2, respectively.The chimerism rate of neutrophil implantation in both children was complete chimerism of donor cells.Implantation syndrome was detected in case 1 following transplantation.Case 2 suffered implantation syndrome, hypertensive encephalopathy, and cytomegalovirus infection following transplantation.Both children showed no graft-versus-host disease (GVHD).Both children had hematopoietic and immune reconstruction after transplantation and their primary diseases were cured.Cases 1 and 2 were followed up for more than 14 and 17 months, respectively.Both of them achieved disease-free survival during the follow up.Literature review of 26 cases with CAMT treated by HSCT, including the above-mentioned 2 cases was conducted, with an overall disease-free survival rate of 92.3%(24/26).Of 12 cases with CAMT typing, 10 were type Ⅰ and 2 were type Ⅱ.Of the 26 cases treated by HSCT, 17 had bone marrow HSCT, with an overall survival rate of 88.2%(15/17), and 2 had peripheral blood HSCT.Seven cases had umbilical cord blood HSCT (6 cases receiving unrelated umbilical cord blood HSCT and 1 case receiving related umbilical cord blood HSCT), with an overall survival rate of 100%.Unlike bone marrow and peripheral blood HSCT, unrelated umbilical cord blood HSCT did not result in 3-4 grade GVHD. Conclusions:Unrelated umbilical cord blood HSCT can achieve good therapeutic effects in CAMT patients when there is no suitable donor.Myeloablative pretreatment is conducive to CAMT patients.