Objective To investigate the role of ATP￣binding cassette ( ABC ) family on the resistance of nasopharyngeal carcinoma (NPC) stem cells (CSCs) to cisplatin. Methods We compared the differences between the drug extravasation capability of CNE￣2 and CNE￣2S by using Rhodamine￣123 efflux assay. We determined the mRNA and protein expression levels of ABC transport family members, including ABCA3,ABCB1,ABCB5,ABCC1,ABCC2 and ABCG2,after 48 h being treated with 1 μmol.L-1 cisplatin by RT￣PC and Western blotting.Rhoamine￣123 efflux and apoptosis by cisplatin in two kinds of cells was examined by ABCA3 gene silencing with specific small￣interfering RNA. Results The IC50 of cisplatin on CNE￣2S was 4.1 fold to that on CNE￣2(P<0.05).For the relative drug effluent activity and Na+K+ ATPase activity,CNE￣2S was 4.8 fold to CNE￣2(P<0.05),suggested that CNE￣2S expressed more ABCA3,ABCB1,ABCC1 and ABCG2 in comparison to CNE￣2(P<0.05).After 48 h treatment with 1 μmol.L-1 cisplatin,ABCA3 specifically highly expressed in CNE￣2S (P<0.05), and knocking down of ABCA3 resulted in reduction of rhodamine￣123 efflux and increase of apoptosis. Conclusion The cisplatin resistance of NPC CSCs is associated with enhanced expression of ABCA3,ABCC1 and ABCG2, suppression of ABCA3 could reverse the resistance of NPC CSCs to cisplatin.

Objective: To compare bioelectrical impedance analysis (BIA) and dual energy X ray absorptiometry (DXA) for measuring body mineral content (BMC) of children and adolescents, and to provide a basis for BIA to accurately measure BMC in children and adolescents. Methods: By using the convenience sampling method, among 1 469 children and adolescents aged 7-17 were recruited in Guangzhou from April to May 2019, the BMC was measured by DXA and BIA. The intraclass correlation coefficient ( ICC ) and Bland Altman analysis were used to evaluate the agreement between BIA and DXA. Bland Altman analysis was performed on log transformed data. The BMC was categorized into age and specific tertiles, and the agreement between methods was evaluated based on the kappa coefficients. Treating the BMC with DXA as the dependent variable, a prediction model was constructed for correcting the BIA measure. Results: The ICC s were 0.93 and 0.94 for boys and girls, respectively. In Bland Altman analysis, the limits of agreements for the BIA to DXA ratio were wide in boys and girls, ranging from 0.27-0.76 and 0.17-0.72, respectively. The kappa coefficients for categorized BMC levels were 0.57 and 0.45 for boys and girls, respectively, showing a fair to good degree of agreement. When sub grouped by BMI, the kappa coefficients for all BMI groups of boys and overweight girls were all >0.75 , with an excellent agreement. The prediction models for boys and girls were as follows: BMC DXA =-0.51+0.44× BMC BIA + 0.06× Age +0.02× BMI ; and BMC DXA =-0.55+0.43× BMC BIA +0.06× Age +0.02× BMI , respectively. The R 2 for models of boys and girls were 0.87 and 0.87, respectively. Conclusion The agreement between BIA and DXA was poor for measuring BMC, but acceptable when evaluating the categorized BMC levels, suggesting the BIA may be applied in assessment of the BMC levels when compared to the age and gender specific population. Additionally, the prediction model for correcting BMC by BIA fis well to the measurement by DXA.

Objective To evaluate the accuracy of bioelectrical impedance analysis(BIA)in measurement of appendicular skeletal muscle mass(ASM)of adults.Methods A total of 836 adults aged 18-42 years were recruited in Guangzhou using a convenient sampling method from April 2021 to September 2022.ASM was measured using BIA and Dual-energy X-ray absorptiometry(DXA).Using DXA as the standard method,the consistency between the BIA and DXA measurements was evaluated by intra-class correlation coefficients(ICCs)and Bland-Altman analysis in logarithmically transformed data,in order to evaluate the accuracy of BIA in ASM measurement.Receiver operating characteristic curve was plotted to evaluate the diagnostic value of BIA for screening low muscle mass.Results A total of 774 individuals were included for analysis finally.ICCs for ASM measured by BIA and DXA were 0.774 and 0.667 in males and females,respectively.Mean ratios(limits of Agreement)of ASM were 0.94(0.80-1.10)and 0.91(0.78-1.05)in males and females,respectively.Area under curve of BIA for screening low muscle mass were 0.91 and 0.94 in males and females,respectively.The optimal cut-off values of Z-score by BIA for males and females were-0.57 and-0.66,respectively.Sensitivity and specificity for males were 82.5%and 86.0%,while being 86.8%and 93.8%,for females.Conclusion BIA shows a moderate consistency with DXA for measuring ASM in adults.Furthermore,BIA yields a good diagnostic value in identifying low muscle mass in adults aged 18-42 years.

OBJECTIVE: To investigate the incidence and infection regularity of ventilator-associated pneumonia (VAP) in patients undergoing tracheal intubation and to provide reference for the prevention and treatment of VAP infection in the future. METHODS: A retrospective study was conducted to collect the microbial data of airway secretion cultures from 72 patients with endotracheal intubation admitted to the emergency ward of Shanghai Fifth People's Hospital from May 2020 to February 2021, and the species of microorganisms and intubation time were statistically analyzed. RESULTS: Among 72 patients with endotracheal intubation, males were more than females (58.33% vs. 41.67%); Patients over 60 years old accounted for 90.28%; pneumonia was the main primary disease, accounting for 58.33%. Pathogenic tests showed that: (1) 72 patients were infected with Acinetobacter baumannii (AB), Klebsiella pneumoniae (KP), and Pseudomonas aeruginosa (PA) 48 hours after intubation, 51.39% (37/72), 27.78% (20/72), and 26.39% (19/72), respectively. The infection rate of AB was significantly higher than that of KP and PA. Within 48 hours of intubation, the infection rates of AB, KP, and PA were 20.83% (15/72), 13.89% (10/72), and 4.17% (3/72), respectively. Of the 42 patients with primary pneumonia, 61.90% (26/42) were infected with one or more of the three pathogenic bacteria AB, KP, and PA 48 hours after intubation, indicating a change in the etiology of the pathogenic bacteria, with the main pathogenic bacteria transitioning from other pathogenic bacteria to AB, KP, and PA. (2) AB, KP, and PA were prone to cause late onset VAP (i.e., intubation ≥ 5 days). Respectively, among VAP patients infected with AB, late onset VAP accounted for 59.46% (22/37). Among patients infected with KP, 75.00% (15/20) had late onset VAP. Among patients infected with PA, late onset VAP accounted for 94.74% (18/19), indicating a higher proportion of late onset VAP caused by PA and KP. (3) Infection was closely related to intubation time, and the pipeline can be replaced according to the peak period of infection. AB and KP infections peaked within 4 days after intubation, reaching 57.69% (30/52) and 50.00% (15/30), respectively. It is recommended to replace the tubes or undergo sensitive antimicrobial therapy around 3-4 days after starting the machine. The proportion of PA infection after 7 days of intubation was 72.73% (16/22), and it was considered to replace the pipeline after 7 days. (4) Most of the three pathogenic bacteria, AB, KP, and PA were carbapenem resistant pathogens with multiple drug resistance. Except for PA, the infection rate of carbapenem resistant bacteria (CRAB, CRKP) was significantly higher than that of non-carbapenem resistant bacteria (AB, KP), accounting for 86.54% (45/52) and 66.67% (20/30) of the corresponding infection cases, respectively, while CRPA only accounts for 18.18% (4/22). CONCLUSIONS The main differences in VAP infection caused by AB, KP, and PA pathogens are infection time, infection probability, and carbapenem resistance. Targeted prevention and treatment measures can be implemented for patients with intubation.
Female ; Male ; Humans ; Middle Aged ; Pneumonia, Ventilator-Associated ; Retrospective Studies ; China ; Intubation, Intratracheal ; Acinetobacter baumannii ; Klebsiella pneumoniae