Objective To fabricate a large-diameter vascular graft with a pore size gradient structure mimicking that of natural blood vessels, using poly-L-lactic acid (PLLA) and polycaprolactone (PCL) as base materials through electrospinning and ultrasonic pore-forming techniques, and to evaluate its application potential. Methods A three-layered tubular graft was fabricated from a PCL/PLLA blend (mass ratio 6 : 4) via electrospinning, followed by an ultrasonic pore-forming process to create a gradient porosity. The resulting graft (diameter: 2 cm, length: 4 cm) was implanted into the descending thoracic aorta of an experimental pig using an end-to-end anastomosis. Graft patency and anastomotic sites were monitored by computed tomography angiography (CTA) at 1 and 6 weeks post-surgery. After 2 months, the graft was explanted for systematic evaluation of vascular regeneration and repair through gross examination, histopathology (H&E and elastic fiber staining), immunohistochemistry [for ETS-related gene (ERG), Actin, and Vimentin], and scanning electron microscopy (SEM). Results Postoperative CTA confirmed excellent graft patency at both 1 and 6 weeks, with no evidence of thrombosis or anastomotic stenosis. Gross examination of the 2-month explant revealed a smooth luminal surface covered by neotissue. Histopathological analysis demonstrated that the graft successfully induced the formation of a three-layered structure resembling a native vessel wall, comprising endothelial cells, smooth muscle cells, and fibroblasts. Immunohistochemistry further verified coverage of the luminal surface by endothelial cells (ERG-positive), along with the presence of neosmooth muscle (Actin-positive) and fibroblasts (Vimentin-positive). Endothelial cells were observed adhering to the inner surface of the artificial vessel under SEM. Conclusion The biomimetic, three-layered PLLA/PCL large-diameter vascular graft, constructed via electrospinning and ultrasonic pore-forming, exhibits excellent short-term patency and biocompatibility in a large animal model. More importantly, it demonstrates a significant potential to promote host cell infiltration and achieve in situ regeneration of a three-layered vascular wall structure, providing a promising experimental basis for the development of next-generation functional vascular substitutes.

An assay was established for detection of toxigenic Clostridioides difficile by combining microfluidic chip analysis with immunochromatography,and its performance was evaluated and compared with those of the Xpert C.difficile/Epi and VIDAS CD AB tests.Primer pairs were designed according to the tcdB and tpi genes in C.difficile.The specificity,limit of detection,reproducibility,and stability were evaluated.A total of 215 stool samples from patients with diarrhea were collected and tested in parallel with the Xpert C.difficile/Epi,VIDAS CDAB,and our assay.C.difficile was isolated from samples,and the tcdB gene was identified when discrepant results were obtained from the three above assays.Our assay showed no cross-reaction with other diarrhea-associated pathogens.Its reproducibility was 100％in testing of two standard plasmids containing tcdB and tpi genes at two concentrations(105 and 102 copies/μL).Two standard plasmids were detected after the PCR and immunochromatography reagents had been stored for 3,6,9,and 12 months,and all the results were posi-tive.The limit of detection was 10 copies/μL for toxigenic C.difficile.Testing of 33 samples positive for C.difficile with our assay(33/215,15.3％)yielded findings statistically coherent with those of the Xpert C.difficile/Epi test(kappa value=0.965).The sensitivity,specificity,positive predictive value,and negative predictive value of our assay,with respect to Xpert C.difficile/Epi as the standard,were 94.3％,100.0％,100.0％,and 98.9％;these values were significantly higher than those of VIDAS CDAB(60.0％,98.9％,91.3％,and 92.7％)(Kappa=0.714,OR=157.50,95％CI:62.03-847.28,P=0.013).In conclusion,our newly developed assay is specific,stable,and reproducible,and may be used for rapid and accu-rate detection of toxigenic C.difficile.The assay could be used for C.difficile infection screening in outpatient and emergen-cy,community medical service center,and epidemiological settings.

Aim To observe the interventional effects of Polygala fallax Hemsl.(PFH)on diabetic kidney disease(DKD)rats and the regulatory mechanism of ferroptosis.Methods Thirty-six SD rats were ran-domly divided into the control group,DKD group,fer-rostatin-1(Fer-1)group,PFH-L group,PFH-M group,and PFH-H group,with six rats in each group.Model-ing was induced by a one-time intraperitoneal injection of 35 mg·kg-1 streptozocin(STZ)in combination with high-sugar and high-fat feed.Ferrostatin-1(25μmol·kg-1)was injected intraperitoneally in Fer-1 group.The PFH-L,PFH-M,and PFH-H groups were gavaged with 50,100 and 200 mg·kg-1 of alcoholic extracts of PFH respectively,and the control and DKD groups were gavaged with an equal volume of distilled water once a day for eight weeks.At the end of drug administration,blood glucose,24h-UP,BUN and Scr levels were measured in each group of rats.HE stai-ning and Masson staining were used to observe renal histopathological changes.ELISA was employed to de-termine the levels of total iron,MDA and GSH activity.IHC was used to observe the expression of Nrf2,SLC7A11,and GPX4 in renal tissues.Western blot was used to detect the protein expression of COL1A1,α-SMA,TGF-,FTH-1,TFR-1,Nrf2,SLC7A1 1,GPX4,in renal tissues.RT-qPCR was used to detect the ex-pression levels of Nrf2,SLC7A11,GPX4 mRNA in re-nal tissues.Results Compared with the control group,blood glucose,24h-UP,BUN,Scr increased(P＜0.05);glomerular volume increased,tubular dilata-tion and collagen fiber deposition were obvious;total i-ron,MDA content increased and GSH activity de-creased(P＜0.05);there was increased protein ex-pression of COL1A1,α-SMA,TGF-β,TFR-1 and de-creased protein expression of FTH-1(P＜0.01);there was decreased mRNA and protein expression of Nrf2,SLC7A11,GPX4 in DKD group rats(P＜0.01).Compared with the DKD group,blood glucose,24h-UP,BUN and Scr decreased(P＜0.05);renal tissue le-sions were significantly reduced;total iron and MDA content decreased,and GSH activity increased(P＜0.05);COL1A1,α-SMA,TGF-β,and TFR-1 protein expression decreased and FTH-1 protein expression in-creased(P＜0.05,P＜0.01);Nrf2,SLC7A11,GPX4 mRNA and protein expression increased in Fer-1 and PFH dose groups(P＜0.05,P＜0.01).Conclusions PFH attenuates renal histopathological injury in DKD rats,and the mechanism may be related to the regula-tion of the Nrf2/SLC7A11/GPX4 signaling pathway.

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.

An assay was established for detection of toxigenic Clostridioides difficile by combining microfluidic chip analysis with immunochromatography,and its performance was evaluated and compared with those of the Xpert C.difficile/Epi and VIDAS CD AB tests.Primer pairs were designed according to the tcdB and tpi genes in C.difficile.The specificity,limit of detection,reproducibility,and stability were evaluated.A total of 215 stool samples from patients with diarrhea were collected and tested in parallel with the Xpert C.difficile/Epi,VIDAS CDAB,and our assay.C.difficile was isolated from samples,and the tcdB gene was identified when discrepant results were obtained from the three above assays.Our assay showed no cross-reaction with other diarrhea-associated pathogens.Its reproducibility was 100％in testing of two standard plasmids containing tcdB and tpi genes at two concentrations(105 and 102 copies/μL).Two standard plasmids were detected after the PCR and immunochromatography reagents had been stored for 3,6,9,and 12 months,and all the results were posi-tive.The limit of detection was 10 copies/μL for toxigenic C.difficile.Testing of 33 samples positive for C.difficile with our assay(33/215,15.3％)yielded findings statistically coherent with those of the Xpert C.difficile/Epi test(kappa value=0.965).The sensitivity,specificity,positive predictive value,and negative predictive value of our assay,with respect to Xpert C.difficile/Epi as the standard,were 94.3％,100.0％,100.0％,and 98.9％;these values were significantly higher than those of VIDAS CDAB(60.0％,98.9％,91.3％,and 92.7％)(Kappa=0.714,OR=157.50,95％CI:62.03-847.28,P=0.013).In conclusion,our newly developed assay is specific,stable,and reproducible,and may be used for rapid and accu-rate detection of toxigenic C.difficile.The assay could be used for C.difficile infection screening in outpatient and emergen-cy,community medical service center,and epidemiological settings.

Aim To observe the interventional effects of Polygala fallax Hemsl.(PFH)on diabetic kidney disease(DKD)rats and the regulatory mechanism of ferroptosis.Methods Thirty-six SD rats were ran-domly divided into the control group,DKD group,fer-rostatin-1(Fer-1)group,PFH-L group,PFH-M group,and PFH-H group,with six rats in each group.Model-ing was induced by a one-time intraperitoneal injection of 35 mg·kg-1 streptozocin(STZ)in combination with high-sugar and high-fat feed.Ferrostatin-1(25μmol·kg-1)was injected intraperitoneally in Fer-1 group.The PFH-L,PFH-M,and PFH-H groups were gavaged with 50,100 and 200 mg·kg-1 of alcoholic extracts of PFH respectively,and the control and DKD groups were gavaged with an equal volume of distilled water once a day for eight weeks.At the end of drug administration,blood glucose,24h-UP,BUN and Scr levels were measured in each group of rats.HE stai-ning and Masson staining were used to observe renal histopathological changes.ELISA was employed to de-termine the levels of total iron,MDA and GSH activity.IHC was used to observe the expression of Nrf2,SLC7A11,and GPX4 in renal tissues.Western blot was used to detect the protein expression of COL1A1,α-SMA,TGF-,FTH-1,TFR-1,Nrf2,SLC7A1 1,GPX4,in renal tissues.RT-qPCR was used to detect the ex-pression levels of Nrf2,SLC7A11,GPX4 mRNA in re-nal tissues.Results Compared with the control group,blood glucose,24h-UP,BUN,Scr increased(P＜0.05);glomerular volume increased,tubular dilata-tion and collagen fiber deposition were obvious;total i-ron,MDA content increased and GSH activity de-creased(P＜0.05);there was increased protein ex-pression of COL1A1,α-SMA,TGF-β,TFR-1 and de-creased protein expression of FTH-1(P＜0.01);there was decreased mRNA and protein expression of Nrf2,SLC7A11,GPX4 in DKD group rats(P＜0.01).Compared with the DKD group,blood glucose,24h-UP,BUN and Scr decreased(P＜0.05);renal tissue le-sions were significantly reduced;total iron and MDA content decreased,and GSH activity increased(P＜0.05);COL1A1,α-SMA,TGF-β,and TFR-1 protein expression decreased and FTH-1 protein expression in-creased(P＜0.05,P＜0.01);Nrf2,SLC7A11,GPX4 mRNA and protein expression increased in Fer-1 and PFH dose groups(P＜0.05,P＜0.01).Conclusions PFH attenuates renal histopathological injury in DKD rats,and the mechanism may be related to the regula-tion of the Nrf2/SLC7A11/GPX4 signaling pathway.

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 symptom improvement effect of a self-made eczema and dermatitis conditioning formula combined with Qingpeng ointment on damp heat type eczema.Methods:A prospective study was conducted on 70 patients with damp heat type eczema ffrom June 2023 to August 2024.Random number table method was used to divide them into two groups.Among them,35 cases were in the single group and treated with Qingpeng plaster alone,while the remaining 35 cases were in the combination group and treated with a self-made eczema and dermatitis conditioning formula orally combined with Qingpeng plaster.After one month of treatment,the clinical efficacy,TCM syndrome scores before and Post-treatment,disappearance time of main symptoms,and the long-term recurrence rate was also compared.Results:The total effective rate of the combined group was 91.43％,which was higher than that of the single group(71.43％,P＜0.05);Before treatment,there was no significant difference in the scores of TCM syndromes between the two groups(P＞0.05).Post-treatment,the scores of TCM syndromes related to the main symptoms(skin erythema,papules,blisters,obvious exudation,severe itching,and burning sensation in the skin lesions)and secondary symptoms(dry mouth,bitter mouth,yellow and red urine,sticky stool or constipation)in both groups decreased,and the combined group was lower than the single group(P＜0.05);The disappearance time of skin burning sensation,exudation,erythema,itching,and skin lesion related symptoms in the combined group was shorter than that in the single group(P＜0.05);Two groups of patients were followed up for six months Post-treatment,and there were no lost cases during the follow-up period.There was no difference between the combined group and the single group(x2=3.214,P=0.073).Conclusion:The combination of self-made eczema and dermatitis conditioning formula and Qingpeng ointment can improve the clinical efficacy of damp heat type eczema,reduce its TCM syndrome score,shorten the duration of main symptoms,and lower the long-term recurrence rate of patients.The mechanism may be related to the regulation of T lymphocyte subsets in eczema patients by the self-made eczema and dermatitis conditioning formula,and the reduction of the body's inflammatory response.

Objective To analyze the risk factors for increased drainage volume after open transforaminal lumbar interbody fusion(TLIF),and to establish a predictive model and then validate it.Methods The clinical data of 680 patients who underwent open TLIF at the General Hospital of Northern Theater Command from January 2016 to December 2019 were collected and the patients were randomly divided into the training group(n=476)and the validation group(n=204).Taking the predictive factors screened out by LASSO regression analysis as independent variables,a multivariate Logistic regression predictive model was constructed.The model was internally validated through the receiver operating characteristic(ROC)curve,Hosmer-Lemeshow goodness-of-fit test,and calibration curve,and its clinical utility was assessed via decision curve analysis(DCA).Results LASSO regression analysis screened out four predictive variables:age,number of surgical segments,operative duration,and intraoperative blood loss.The multivariate Logistic regression predictive model demonstrated that age≥60 years,number of surgical segments≥4,operative duration≥2 hours,and intraoperative blood loss≥200 mL were independent influencing factors for the increased postoperative drainage volume in patients undergoing TLIF(P<0.05).ROC curve analysis revealed an area under the curve(AUC)of 0.816(95%CI:0.798 to 0.867)in the training group and 0.783(95%CI:0.685 to 0.823)in the validation group,indicating that the predictive model had good discriminatory ability.Additionally,the Hosmer-Lemeshow goodness-of-fit test and calibration curve indicated that the predictive model had a good degree of fit,and the predicted probability was basically consistent with the actual probability,demonstrating a good calibration.The DCA results confirmed that this predictive model could be applied in clinical practice.Conclusion The risk factors for increased drainage volume after open TLIF include age,number of surgical segments,operative duration,and intraoperative blood loss.The predictive model established based on these factors demonstrates good performance,and it can be applied in clinical guidance for the selection of drainage tube removal time after TLIF.

Objective:To explore the symptom improvement effect of a self-made eczema and dermatitis conditioning formula combined with Qingpeng ointment on damp heat type eczema.Methods:A prospective study was conducted on 70 patients with damp heat type eczema ffrom June 2023 to August 2024.Random number table method was used to divide them into two groups.Among them,35 cases were in the single group and treated with Qingpeng plaster alone,while the remaining 35 cases were in the combination group and treated with a self-made eczema and dermatitis conditioning formula orally combined with Qingpeng plaster.After one month of treatment,the clinical efficacy,TCM syndrome scores before and Post-treatment,disappearance time of main symptoms,and the long-term recurrence rate was also compared.Results:The total effective rate of the combined group was 91.43％,which was higher than that of the single group(71.43％,P＜0.05);Before treatment,there was no significant difference in the scores of TCM syndromes between the two groups(P＞0.05).Post-treatment,the scores of TCM syndromes related to the main symptoms(skin erythema,papules,blisters,obvious exudation,severe itching,and burning sensation in the skin lesions)and secondary symptoms(dry mouth,bitter mouth,yellow and red urine,sticky stool or constipation)in both groups decreased,and the combined group was lower than the single group(P＜0.05);The disappearance time of skin burning sensation,exudation,erythema,itching,and skin lesion related symptoms in the combined group was shorter than that in the single group(P＜0.05);Two groups of patients were followed up for six months Post-treatment,and there were no lost cases during the follow-up period.There was no difference between the combined group and the single group(x2=3.214,P=0.073).Conclusion:The combination of self-made eczema and dermatitis conditioning formula and Qingpeng ointment can improve the clinical efficacy of damp heat type eczema,reduce its TCM syndrome score,shorten the duration of main symptoms,and lower the long-term recurrence rate of patients.The mechanism may be related to the regulation of T lymphocyte subsets in eczema patients by the self-made eczema and dermatitis conditioning formula,and the reduction of the body's inflammatory response.