Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

The continuous accumulation of plastic waste such as polyethylene in the environment has caused serious environmental pollution issues.Considering the high similarity in the molecular structure of petroleum and polyolefin,it is feasible to apply rare earth-zeolite catalysts in polyolefin plastic upcycling,which is commonly used in fluid catalytic cracking(FCC)in the field of petroleum refining.In this study,Ce-modified HY(Ce-HY)zeolites were synthesized and characterized by a series of analytical methods,such as high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM),Fourier infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),etc.When introducing 5% Ce species into HY zeolites,the 5Ce-HY showed excellent catalytic performance in the catalytic cracking of low-density polyethylene(LDPE),which achieved 98.4% LDPE conversion with 91.5% selectivity of gaseous alkanes at 300℃,and 75.4% of them were isoparaffins.In addition,the effect of the location of rare earth species in Y zeolites on the catalytic performance was explored by fine X-ray diffraction(XRD)in the range of 11°-13°and in situ-Raman analyses.The Ce species located in the supercage of Y zeolites were more important,which enhanced the adsorption capacity and accessibility of substrate molecules,thus facilitating the entire catalytic cracking process.This method could be used to detect the location of rare earth elements in Y zeolites to understand the mechanism of rare earth catalysis.

Objective:To analyze the risk factors for human cytomegalovirus (HCMV) infection in pediatric recipients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT).Methods:Clinical data of children who underwent first allo-HSCT were retrospectively analyzed from March 2017 to November 2024. A total of 259 pediatric allo-HSCT recipients were analyzed through comparing HCMV infection group (n=115) and Non-HCMV infection group (n=144). Clinical characteristics were compared, and risk factors for HCMV infection were analyzed using univariate and multivariate logistic regression.Results:The result of univariate analysis showed that adrenoleukodystrophy (ALD), length of hospitalization, duration of antiviral therapy, and bacterial infection were significantly associated with HCMV infection in pediatric allo-HSCT recipients ( P<0.05). The result of multivariate analysis showed that ALD was an independent protective factor against HCMV infection of allo-HSCT recipients ( P<0.05) [OR=0.22, 95% CI: 0.06-0.86], while umbilical cord blood transplantation (UCBT) was an independent risk factor for HCMV infection in allo-HSCT recipients ( P<0.05) [OR=6.13, 95% CI: 1.34-28.04]. When the area under the ROC curve (AUC) for predicting post-transplant relapse based on HCMV viral load was 0.75 (95% CI: 0.55-0.94, P=0.014) and at the cutoff value of 3×10 3 copies/ml, the sensitivity and specificity for predicting relapse were 81.13% and 66.67%, respectively. Conclusions:HCMV infection in pediatric allo-HSCT recipients may lead to longer hospitalization and increased risk of relapse.

Objective:To determine the epidemiological characteristics of human bocavirus (HBoV) in children with acute respiratory infections (ARI) in Bengbu City, Anhui Province, in 2024.Methods:Nasopharyngeal swab samples were collected from 269 children with ARI in Bengbu City, Anhui Province, in 2024. Seventeen respiratory pathogens were screened using quantitative fluorescence PCR. For HBoV-positive samples, the VP1/VP2 structural gene fragments of HBoV were amplified and sequenced for genetic evolutionary analysis.Results:Among the 269 nasopharyngeal swab samples from children with ARI, the overall detection rate of respiratory pathogens was 48.33% (103/269). The top three pathogens with the highest detection rates were: Influenza A virus (FluA): 10.04% (27/269), Respiratory syncytial virus (RSV): 8.18% (22/269), Human bocavirus (HBoV): 7.43% (20/269). The age distribution of HBoV-infected children showed that the detection rate was highest in the 0-2 years age group (50%, 10/20), followed by the 3-5 years age group (25%, 5/20) and the over 6 years age group (25%, 5/20). However, there was no statistically significant difference in viral detection rates among the age groups. Genetic evolutionary analysis based on VP1/VP2 revealed that all 13 HBoV strains were of the HBoV-1 genotype.Conclusions:HBoV is one of the major pathogens causing ARI in children in Bengbu City, Anhui Province, in 2024, with HBoV-1 being the predominant genotype. Additionally, infants aged 0-2 years are the most susceptible population to HBoV infection.

Objective:To analyze the clinical characteristics and cytokines expression characteristics in infants with mild and severe respiratory syncytial virus (RSV) infection.Methods:From May 2023 to December 2023, plasma samples and clinical information were collected from 16 infants with RSV infection and 14 control infants. Cytek Aurora flow cytometry (Cytek, America) and Enzyme linked immunosorbent assay (ELISA) were used to detect the expression levels of 25 cytokines after mild and severe RSV infection.Results:Cough and nasal obstruction were the main clinical manifestations in infants with mild RSV infection, accompanied by polypnea, wheezing and other symptoms. The main symptoms of severe RSV infection were cough and rales, accompanied by fever and polypnea. In comparison with the control group, the expression levels of IL-2, IL-4, IL-5, IL-6, IL-9, IL-13, IL-22, TNF-α, IFN-α, IFN-β, MIP-1β, I-TAC, ENA-78, GROα, Eotaxin, and MCP-1 in the RSV infection group all exhibited an upregulation trend. Both IP-10 and MIP-3α demonstrated a downward trend in the RSV infection group; however, there was no statistically significant difference ( P>0.05). The levels of IL-10, IFN-γ, MIP-1α, and IL-8 in the RSV infection group were significantly higher than those in the control group, whereas the levels of MIG, TARC, and RANTES in the RSV infection group were significantly lower than those in the control group ( P<0.05). The levels of IL-2, IL-4, IL-5, IL-6, IL-9, IL-10, IL-13, IL-22, IFN-β, IFN-γ, TNF-α, IL-8, I-TAC, MIP-1β, Eotaxin, and MCP-1 in the mild RSV infection group were significantly higher than those in the severe RSV infection group ( P>0.05). Among these, the levels of MIG, RANTES, TARC, MIP-3α, and ENA-78 in the mild infection group were all lower than those in the severe infection group. The expressions of ENA-78 and MIP-1α in the severe infection group were significantly higher than those in the mild infection group and also higher than those in the control group. There was no significant difference in IP-10 and GROα between the mild and severe RSV infection groups ( P>0.05). Conclusions:The differences in clinical features and cytokines between infants with mild and severe RSV infection provide important data support for the prevention and treatment of RSV infection in infants.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

Objective:To analyze the risk factors for human cytomegalovirus (HCMV) infection in pediatric recipients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT).Methods:Clinical data of children who underwent first allo-HSCT were retrospectively analyzed from March 2017 to November 2024. A total of 259 pediatric allo-HSCT recipients were analyzed through comparing HCMV infection group (n=115) and Non-HCMV infection group (n=144). Clinical characteristics were compared, and risk factors for HCMV infection were analyzed using univariate and multivariate logistic regression.Results:The result of univariate analysis showed that adrenoleukodystrophy (ALD), length of hospitalization, duration of antiviral therapy, and bacterial infection were significantly associated with HCMV infection in pediatric allo-HSCT recipients ( P<0.05). The result of multivariate analysis showed that ALD was an independent protective factor against HCMV infection of allo-HSCT recipients ( P<0.05) [OR=0.22, 95% CI: 0.06-0.86], while umbilical cord blood transplantation (UCBT) was an independent risk factor for HCMV infection in allo-HSCT recipients ( P<0.05) [OR=6.13, 95% CI: 1.34-28.04]. When the area under the ROC curve (AUC) for predicting post-transplant relapse based on HCMV viral load was 0.75 (95% CI: 0.55-0.94, P=0.014) and at the cutoff value of 3×10 3 copies/ml, the sensitivity and specificity for predicting relapse were 81.13% and 66.67%, respectively. Conclusions:HCMV infection in pediatric allo-HSCT recipients may lead to longer hospitalization and increased risk of relapse.

Objective:To determine the epidemiological characteristics of human bocavirus (HBoV) in children with acute respiratory infections (ARI) in Bengbu City, Anhui Province, in 2024.Methods:Nasopharyngeal swab samples were collected from 269 children with ARI in Bengbu City, Anhui Province, in 2024. Seventeen respiratory pathogens were screened using quantitative fluorescence PCR. For HBoV-positive samples, the VP1/VP2 structural gene fragments of HBoV were amplified and sequenced for genetic evolutionary analysis.Results:Among the 269 nasopharyngeal swab samples from children with ARI, the overall detection rate of respiratory pathogens was 48.33% (103/269). The top three pathogens with the highest detection rates were: Influenza A virus (FluA): 10.04% (27/269), Respiratory syncytial virus (RSV): 8.18% (22/269), Human bocavirus (HBoV): 7.43% (20/269). The age distribution of HBoV-infected children showed that the detection rate was highest in the 0-2 years age group (50%, 10/20), followed by the 3-5 years age group (25%, 5/20) and the over 6 years age group (25%, 5/20). However, there was no statistically significant difference in viral detection rates among the age groups. Genetic evolutionary analysis based on VP1/VP2 revealed that all 13 HBoV strains were of the HBoV-1 genotype.Conclusions:HBoV is one of the major pathogens causing ARI in children in Bengbu City, Anhui Province, in 2024, with HBoV-1 being the predominant genotype. Additionally, infants aged 0-2 years are the most susceptible population to HBoV infection.

Objective:To analyze the clinical characteristics and cytokines expression characteristics in infants with mild and severe respiratory syncytial virus (RSV) infection.Methods:From May 2023 to December 2023, plasma samples and clinical information were collected from 16 infants with RSV infection and 14 control infants. Cytek Aurora flow cytometry (Cytek, America) and Enzyme linked immunosorbent assay (ELISA) were used to detect the expression levels of 25 cytokines after mild and severe RSV infection.Results:Cough and nasal obstruction were the main clinical manifestations in infants with mild RSV infection, accompanied by polypnea, wheezing and other symptoms. The main symptoms of severe RSV infection were cough and rales, accompanied by fever and polypnea. In comparison with the control group, the expression levels of IL-2, IL-4, IL-5, IL-6, IL-9, IL-13, IL-22, TNF-α, IFN-α, IFN-β, MIP-1β, I-TAC, ENA-78, GROα, Eotaxin, and MCP-1 in the RSV infection group all exhibited an upregulation trend. Both IP-10 and MIP-3α demonstrated a downward trend in the RSV infection group; however, there was no statistically significant difference ( P>0.05). The levels of IL-10, IFN-γ, MIP-1α, and IL-8 in the RSV infection group were significantly higher than those in the control group, whereas the levels of MIG, TARC, and RANTES in the RSV infection group were significantly lower than those in the control group ( P<0.05). The levels of IL-2, IL-4, IL-5, IL-6, IL-9, IL-10, IL-13, IL-22, IFN-β, IFN-γ, TNF-α, IL-8, I-TAC, MIP-1β, Eotaxin, and MCP-1 in the mild RSV infection group were significantly higher than those in the severe RSV infection group ( P>0.05). Among these, the levels of MIG, RANTES, TARC, MIP-3α, and ENA-78 in the mild infection group were all lower than those in the severe infection group. The expressions of ENA-78 and MIP-1α in the severe infection group were significantly higher than those in the mild infection group and also higher than those in the control group. There was no significant difference in IP-10 and GROα between the mild and severe RSV infection groups ( P>0.05). Conclusions:The differences in clinical features and cytokines between infants with mild and severe RSV infection provide important data support for the prevention and treatment of RSV infection in infants.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]