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 develop a bacterial endotoxin detection method suitable for mRNA vaccines based on lipid nanoparticle（LNP）delivery system.Methods:The gel clot limit test outlined in the third section of the Chinese Pharmacopoeia（2020 edition）was utilized. Taking the human herpesvirus type 2 mRNA vaccine as the detection object，the optimal conditions for bacterial endotoxin detection were established by evaluating sample dilution factors，diluents，and other interfering elements. The results were validated using the recombinant C factor method. Finally，the applicability of the established method was validated through testing the respiratory syncytial virus mRNA vaccine and the shingles mRNA vaccine.Results:Increasing the sample dilution factor to 480 times with a magnesium-containing buffer and using 0.06 EU/ml tachypleus amebocyte lysate effectively mitigated the interference caused by LNP on the test results of the human herpesvirus type 2 mRNA vaccine，the respiratory syncytial virus mRNA vaccine，and the shingles mRNA vaccine. The results from recombinant C factor method and the gel clot limit method were consistent.Conclusion:A bacterial endotoxin gel clot limit detection method tailored for human herpesvirus type 2 mRNA vaccine，respiratory syncytial virus mRNA vaccine，and shingles mRNA vaccine is successfully developed based on existing protocols in the Chinese Pharmacopoeia（2020 edition）. This study offers insights for the detection of bacterial endotoxin in LNP-based biological products.

Obstructive sleep apnea(OSA)is a dis-order characterized by chronic intermittent hypoxia and sleep fragmentation,usually manifested by ob-struction of the upper respiratory tract,resulting in sleep fragmentation,intermittent hypoxia,and hy-percapnia.OSA and significant comorbidities are as-sociated with perioperative complications.Opioids,as the most commonly used pain relievers,may fur-ther affect perioperative pain management in OSA and comorbidities.Studies have shown that OSA patients are more susceptible to the respiratory de-pressant effects of opioids.OSA also increases the risk of opioid-induced respiratory depression.There-fore,understanding the effects and mechanisms of opioids on OSA has important clinical significance for optimizing drug use,improving prognosis,and reducing respiratory adverse events.This article aims to review the effects of opioids on OSA and their relationship.

Obstructive sleep apnea(OSA)is a dis-order characterized by chronic intermittent hypoxia and sleep fragmentation,usually manifested by ob-struction of the upper respiratory tract,resulting in sleep fragmentation,intermittent hypoxia,and hy-percapnia.OSA and significant comorbidities are as-sociated with perioperative complications.Opioids,as the most commonly used pain relievers,may fur-ther affect perioperative pain management in OSA and comorbidities.Studies have shown that OSA patients are more susceptible to the respiratory de-pressant effects of opioids.OSA also increases the risk of opioid-induced respiratory depression.There-fore,understanding the effects and mechanisms of opioids on OSA has important clinical significance for optimizing drug use,improving prognosis,and reducing respiratory adverse events.This article aims to review the effects of opioids on OSA and their relationship.

Objective:To develop a bacterial endotoxin detection method suitable for mRNA vaccines based on lipid nanoparticle（LNP）delivery system.Methods:The gel clot limit test outlined in the third section of the Chinese Pharmacopoeia（2020 edition）was utilized. Taking the human herpesvirus type 2 mRNA vaccine as the detection object，the optimal conditions for bacterial endotoxin detection were established by evaluating sample dilution factors，diluents，and other interfering elements. The results were validated using the recombinant C factor method. Finally，the applicability of the established method was validated through testing the respiratory syncytial virus mRNA vaccine and the shingles mRNA vaccine.Results:Increasing the sample dilution factor to 480 times with a magnesium-containing buffer and using 0.06 EU/ml tachypleus amebocyte lysate effectively mitigated the interference caused by LNP on the test results of the human herpesvirus type 2 mRNA vaccine，the respiratory syncytial virus mRNA vaccine，and the shingles mRNA vaccine. The results from recombinant C factor method and the gel clot limit method were consistent.Conclusion:A bacterial endotoxin gel clot limit detection method tailored for human herpesvirus type 2 mRNA vaccine，respiratory syncytial virus mRNA vaccine，and shingles mRNA vaccine is successfully developed based on existing protocols in the Chinese Pharmacopoeia（2020 edition）. This study offers insights for the detection of bacterial endotoxin in LNP-based biological products.

Objective:To compare the clinical features of severe Mycoplasma pneumoniae pneumonia (SMPP) in pediatric intensive care units (PICU) before and after the COVID-19 pandemic.Methods:A retrospective study was conducted in the PICU of Shanghai Children's Hospital. Clinical and laboratory data were collected from medical records of SMPP patients admitted to the PICU before (January to December 2019) and after (March 2023 to February 2024) the COVID-19 pandemic. Patients admitted in 2019 were categorized as the pre-COVID-19 group, while those admitted in 2023-2024 were classified as the post-COVID-19 group.Results:A total of 287 children with SMPP were included, comprising 155 males and 132 females. The pre-pandemic group consisted of 180 cases, while the post-pandemic group had 107 cases. Macrolide-resistant Mycoplasma pneumoniae (MRMP) was detected in 270 cases (94.1%), with no significant difference in MRMP prevalence between the two groups [101 cases (94.4%) vs. 169 cases (93.9%), Z= 0.031, P = 0.861]. The median age of the post-pandemic group was higher than that of the pre-pandemic group [72 (42, 108) months vs. 42 (24, 68) months, Z= 6.438, P < 0.001].Comparisons of complications between the post-pandemic and pre-pandemic groups were as follows: pleural effusion [20 cases (18.7%) vs. 81 cases (45.0%), χ2=20.365, P< 0.001], shock [4 cases (3.7%) vs. 79 cases (43.9%), χ2=52.628, P< 0.001], gastrointestinal dysfunction [2 cases (1.9%) vs. 24 cases (13.3%), χ 2=9.359, P=0.002], liver dysfunction [9 cases (8.4%) vs. 46 cases (25.6%), χ2=12.733, P< 0.001], and renal injury [0 cases vs. 10 cases (5.6%), P=0.015].There was no significant difference in the incidence of respiratory failure [102 cases (95.3%) vs. 172 cases (95.6%), χ2=0.008, P=0.928]. However, the number of cases requiring high-flow oxygen therapy and mechanical ventilation was significantly lower in the post-pandemic group compared to the pre-pandemic group [14 cases (13.3%) vs. 48 cases (26.7%), 21 cases (20.3%) vs. 122 cases (67.8%), all P<0.05].The time from symptom onset to the initiation of tetracycline/quinolone therapy was shorter in the post-pandemic group compared to the pre-pandemic group [7 (3, 10) days vs. 9 (6.3, 11) days, χ2=-3.565, P< 0.001]. The proportion of patients who had already received tetracycline/quinolone therapy before admission to the PICU was significantly higher in the post-pandemic group compared to the pre-pandemic group [25 cases (23.4%) vs. 2 cases (1.1%), χ 2=10.009, P=0.002].Both the total hospital stay and PICU stay were shorter in the post-pandemic group compared to the pre-pandemic group [10.0 (8.0, 14.0) days vs. 15.5 (12.0, 22.0) days, 5 (3.0, 8.0) days vs. 7.0 (5.0, 10.0) days, all P=0.000]. All 7 deaths occurred in the pre-pandemic group, including 5 cases with co-infections and 2 cases with underlying diseases. Conclusions:In the post-COVID-19 era, SMPP cases in the PICU were predominantly observed in children over 5 years old, with a lower incidence of shock, gastrointestinal disorders, liver injury, and kidney injury compared to the pre-pandemic period. Patients with macrolide-resistant Mycoplasma pneumoniae who received timely treatment with tetracycline/quinolones exhibited favorable outcomes.

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.

Hypoxic pulmonary hypertension(HPH)is a kind of chronic high-altitude sickness disease,which is also the initiation link of high-altitude sickness such as pneumocardial disease and high-altitude pulmonary edema.Its main features are persistent vasoconstriction and irreversible remodeling of blood vessels.HPH has greatly impacted the health of people in the plat-eau section.As a typical representative of ethnic medicine,Zang medicine embodies the wisdom of the Zang people in their long-term struggle against diseases.Adapting to local conditions for a long time,Zang medicine has unique advantages in the treatment of HPH.By reviewing the pathogenesis of HPH and the research of single Zang medicine and the complex prescription of Zang medicine in the treatment of HPH,this article aims to provide a theoretical basis for the physiological and pathological research of HPH and to provide a reference for the clinical application of Zang medicine.

Neurofibromatosis type 1（NF1）is one of the most common autosomal dominant disorders. The disease is caused by mutations in the NF1 gene，which can involve multiple systems and have a variety of clinical manifestations，including café au lait macules，lisch nodules，neuroglioma，autism spectrum disorder，learning difficulties，neurofibromas，and skeletal dysplasia，et al.In previous studies on the pathogenesis of NF1，most of them have focused on the regulation of the RAS signaling pathway by neurofibromin. In recent years，researchers start exploring pathways other than RAS signaling to explore the potential functions of neurofibromin. This article reviews the research progress on the pathogenesis of NF1 in recent years，aiming to provide new ideas for treatment.

Objective:To investigate the etiological distribution of hydronephrosis caused by upper uri-nary tract obstruction in adult patients and to improve the diagnostic accuracy for this condition.Me-thods:The clinical information of adult patients with newly diagnosed hydronephrosis in Upper Urinary Tract Repair Outpatient Clinic of Peking University First Hospital from May 2020 to May 2021 were pro-spectively and continuously collected.Patients with ureteral calculi or upper urinary tract tumor were ex-cluded.A total of 767 patients were involved.The underlying causes of upper urinary tract obstruction were identified by senior urological surgeons according to symptoms,medical history,physical examina-tion,and a range of diagnostic imaging techniques including ultrasound,computed tomography(CT),magnetic resonance imaging(MRI),retrograde pyelography,antegrade pyelography,radionuclide reno-gram and ureteroscopy.Results:Among the 767 patients,359(46.8％)were male and 408(53.2％)were female.The median age of these patients was 37 years(range,14-84 years).Hydronephrosis was observed at left-sided in 357 cases(46.6％),right-sided in 251 cases(32.7％),and bilateral in 159 cases(20.7％).The causes of hydronephrosis were classified as follows:(1)Non-iatrogenic factors were found in 464 cases(60.5％).These included urinary malformations in 355 cases(76.5％),infec-tion in 29 cases(6.3％),pelvic lipomatosis and/or cystitis glandularis in 23 cases(5.0％),ureteral en-dometriosis in 18 cases(3.9％),retroperitoneal fibrosis in 15 cases(3.2％),trauma in 7 cases(1.5％)and other non-iatrogenic factors in 12 cases(2.6％).Some of these patients had multiple non-iatrogenic causes.Among the 355 cases with urinary system malformations,252 cases(71.0％)had ureteropelvic junction obstruction.(2)Iatrogenic ureteral injuries accounted for 210 cases(27.4％),including 112 cases(53.3％)of urological surgical injuries,51 cases(24.3％)of radiotherapy for malignant tumor re-lated injuries,34 cases(16.2％)of gynecological and obstetrical surgical injuries,and 13 cases(6.2％)of general surgical injuries.(3)The cause of hydronephrosis remained unknown in 93 cases(12.1％).Conclusion:Hydronephrosis in adults due to upper urinary tract obstruction has a diverse range of cau-ses,with urinary malformations and iatrogenic ureteral injuries being significant contributors.Urological surgeon involved in upper urinary tract reconstruction should be familiar with these potential causes to fa-cilitate accurate diagnosis and effective treatment.