Human Respiratory Stem Cells (RSCs) play a crucial role in the maintenance, repair and regeneration of the respiratory system. As a novel therapeutic method, stem cell therapy is a popular research direction in the medical field. And with the in-depth research on the mechanism of pneumonia caused by respiratory infections in recent years, the use of RSCs to explore pneumonia caused by respiratory infections and its therapeutic strategies has become a hot topic. In this paper, we firstly outlined the types of RSCs, summarized the mechanism of pneumonia caused by respiratory tract infections, discussed the advantages of RSCs application and the progress of culture differentiation, and elaborated the therapeutic exploration of RSCs in pneumonia caused by respiratory tract infections.

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 study the effect of medial collateral ligament(MCL)release on the squatting motion followling total knee arthroplasty(TKA)and provide reference data for ligament release during knee replacement surgery.Methods Based on CT and MRI images of a volunteer,a three-dimensional(3D)geometric anatomical model of the natural knee joint including bone tissues and major soft tissues was established.A finite element model of the artificial knee joint was established by simulating TKA surgery.The squatting motion after 30％release of the upper end,lower end,and both ends of the MCL was simulated,and motion characteristic data of the knee joint at flexion/extension angles from 0° to 135° were obtained.Results The effects of ligament release at different locations on knee squatting motion varied.After releasing the lower end,the medial translation,posterior translation,superior translation,and adduction of the femur relative to the tibia increased by 13.74％,3.83％,9.74％,and 2.37％,respectively,while the external rotation decreased by 36.8％.After releasing the upper end,the medial translation and posterior translation increased by 10.65％and 10％,respectively,while the superior translation,adduction,and external rotation decreased by 4.52％,33.89％,and 67.1％,respectively.After releasing both ends,the medial translation,posterior translation,and superior translation increased by 14.77％,9.39％,and 22.56％,respectively,while the adduction and external rotation decreased by 15.62％and 47.3％,respectively.Conclusions After MCL released,the medial translation,anterior translation,superior translation,and abduction of the femur relative to the tibia increased,while the external rotation decreased.Releasing the lower end had the least effect on these femoral movements,showing an obvious advantage.

Objective To study the effect of medial collateral ligament(MCL)release on the squatting motion followling total knee arthroplasty(TKA)and provide reference data for ligament release during knee replacement surgery.Methods Based on CT and MRI images of a volunteer,a three-dimensional(3D)geometric anatomical model of the natural knee joint including bone tissues and major soft tissues was established.A finite element model of the artificial knee joint was established by simulating TKA surgery.The squatting motion after 30％release of the upper end,lower end,and both ends of the MCL was simulated,and motion characteristic data of the knee joint at flexion/extension angles from 0° to 135° were obtained.Results The effects of ligament release at different locations on knee squatting motion varied.After releasing the lower end,the medial translation,posterior translation,superior translation,and adduction of the femur relative to the tibia increased by 13.74％,3.83％,9.74％,and 2.37％,respectively,while the external rotation decreased by 36.8％.After releasing the upper end,the medial translation and posterior translation increased by 10.65％and 10％,respectively,while the superior translation,adduction,and external rotation decreased by 4.52％,33.89％,and 67.1％,respectively.After releasing both ends,the medial translation,posterior translation,and superior translation increased by 14.77％,9.39％,and 22.56％,respectively,while the adduction and external rotation decreased by 15.62％and 47.3％,respectively.Conclusions After MCL released,the medial translation,anterior translation,superior translation,and abduction of the femur relative to the tibia increased,while the external rotation decreased.Releasing the lower end had the least effect on these femoral movements,showing an obvious advantage.

Human Respiratory Stem Cells (RSCs) play a crucial role in the maintenance, repair and regeneration of the respiratory system. As a novel therapeutic method, stem cell therapy is a popular research direction in the medical field. And with the in-depth research on the mechanism of pneumonia caused by respiratory infections in recent years, the use of RSCs to explore pneumonia caused by respiratory infections and its therapeutic strategies has become a hot topic. In this paper, we firstly outlined the types of RSCs, summarized the mechanism of pneumonia caused by respiratory tract infections, discussed the advantages of RSCs application and the progress of culture differentiation, and elaborated the therapeutic exploration of RSCs in pneumonia caused by respiratory tract infections.

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.