OBJECTIVE: To prepare clinical-grade human umbilical cord-derived mesenchymal stem cells (hUC-MSC) with high expression of hematopoietic supporting factors and evaluate their stem cell characteristics. METHODS: Fetal umbilical cord tissues were collected from healthy postpartum women during full-term cesarean section. Wharton's jelly was mechanically separated and hUC-MSCs were obtained by explant culture method and enzyme digestion method in an animal serum-free culture system with addition of human platelet lysate. The phenotypic characteristics of hUC-MSCs obtained by two methods were detected by flow cytometry. The differences in proliferation ability between the two groups of hUC-MSCs were identified through CCK-8 assay and colony forming unit-fibroblast (CFU-F) assay. The differences in multilineage differentiation potential between the two groups of hUC-MSCs were identified through induction of adipogenic, osteogenic, and chondrogenic differentiation. The mRNA expression levels of hematopoietic supporting factors such as SCF, IL-3, CXCL12, VCAM1 and ANGPT1 in the two groups of hUC-MSCs were identified by real-time fluorescence quantiative PCR(RT-qPCR). RESULTS: The results of flow cytometry showed that hUC-MSCs obtained by the two methods both expressed high levels of CD73, CD90 and CD105, while lowly expressed CD31, CD45 and HLA-DR. The results of CCK-8 and CFU-F assay showed that the proliferation ability of hUC-MSCs obtained by explant culture method was better than those obtained by enzyme digestion method. The results of the triple lineage differentiation experiment showed that there was no significant difference in multilineage differentiation potential between the two grous of hUC-MSCs. The results of RT-qPCR showed that the mRNA expression levels of hematopoietic supporting factors SCF, IL-3, CXCL12, VCAM1 and ANGPT1 in hUC-MSCs obtained by explant cultrue method were higher than those obtained by enzyme digestion method. CONCLUSION Clinical-grade hUC-MSCs with high expression levels of hematopoietic supporting factors were successfully cultured in an animal serum-free culture system.
Humans ; Mesenchymal Stem Cells/metabolism* ; Umbilical Cord/cytology* ; Cell Differentiation ; Female ; Cell Proliferation ; Cells, Cultured ; Chemokine CXCL12/metabolism* ; Angiopoietin-1/metabolism* ; Vascular Cell Adhesion Molecule-1/metabolism* ; Stem Cell Factor/metabolism* ; Flow Cytometry ; Pregnancy

With the rapid development of generative artificial intelligence(GAI)technologies,their widespread application in academic research and writing is continuously expanding the boundaries of sci-entific inquiry.However,this trend has also raised a series of ethical and regulatory challenges,inclu-ding issues related to authorship,content authenticity,citation accuracy,and accountability.In light of the growing involvement of AI in generating academic content,establishing an open,controllable,and trustworthy ethical governance framework has become a key task for safeguarding research integrity and maintaining trust within the academic community.This expert consensus outlines ethical requirements across key stages of AI-assisted academic writing-including topic selection,data management,citation practices,and authorship attribution.It aims to clarify the boundaries and ethical obligations surrounding AI use in academic writing,ensuring that technological tools enhance efficiency without compromising in-tegrity.The goal is to provide guidance and institutional support for building a responsible and sustainable research ecosystem.

With the rapid development of generative artificial intelligence(GAI)technologies,their widespread application in academic research and writing is continuously expanding the boundaries of sci-entific inquiry.However,this trend has also raised a series of ethical and regulatory challenges,inclu-ding issues related to authorship,content authenticity,citation accuracy,and accountability.In light of the growing involvement of AI in generating academic content,establishing an open,controllable,and trustworthy ethical governance framework has become a key task for safeguarding research integrity and maintaining trust within the academic community.This expert consensus outlines ethical requirements across key stages of AI-assisted academic writing-including topic selection,data management,citation practices,and authorship attribution.It aims to clarify the boundaries and ethical obligations surrounding AI use in academic writing,ensuring that technological tools enhance efficiency without compromising in-tegrity.The goal is to provide guidance and institutional support for building a responsible and sustainable research ecosystem.

Objective:To investigate the effects and underlying mechanism of ionizing radiation on the adipogenic of mesenchymal stem cells(MSCs).Methods:Mouse MSCs were cultured in vitro and treated with 2 Gy and 6 Gy radiation with 60Co,and the radiation dose rate was 0.98 Gy/min.Bulk RNA-seq was performed on control and irradiated MSCs.The changes of adipogenic differentiation and oxidative stress pathways of MSC were revealed by bioinformatics analysis.Oil Red O staining was used to detect the adipogenic differentiation ability of MSCs in vitro,and real-time fluorescence quantitative PCR(qPCR)was used to detect the expression differences of key regulatory factors Cebpa,Lpl and Pparg after radiation treatment.At the same time,qPCR and Western blot were used to detect the effect of inhibition of Nrf2,a key factor of antioxidant stress pathway,on the expression of key regulatory factors of adipogenesis.Moreover,the species conservation of the irradiation response of human bone marrow MSCs and mouse MSC was determined by qPCR.Results:Bulk RNA-seq suggested that ionizing radiation promotes adipogenic differentiation of MSCs and up-regulation of oxidative stress-related genes and pathways.The results of Oil Red O staining and qPCR showed that ionizing radiation promoted the adipogenesis of MSCs,with high expression of Cebpa,Lpl and Pparg,as well as oxidative stress-related gene Nrf2.Nrf2 pathway inhibitors could further enhance the adipogenesis of MSCs in bone marrow after radiation.Notably,the similar regulation of oxidative pathways and enhanced adipogenesis post irradiation were observed in human bone marrow MSCs.In addition,irradiation exposure led to up-regulated mRNA expression of interleukin-6 and down-regulated mRNA expression of colony stimulating factor 2 in human bone marrow MSCs.Conclusion:Ionizing radiation promotes adipogenesis of MSCs in mice,and oxidative stress pathway participates in this effect,blocking Nrf2 further promotes the adipogenesis of MSCs.Additionally,irradiation activates oxidative pathways and promotes adipogenic differentiation of human bone marrow MSCs.

Objective:To establish an in vitro cell model simulating acute graft-versus-host disease(aGVHD)bone marrow microenvironment injury with the advantage of mouse serum of aGVHD model and explore the effect of serum of aGVHD mouse on the adipogenic differentiation ability of mesenchymal stem cells(MSCs).Methods:The 6-8-week-old C57BL/6N female mice and BALB/c female mice were used as the donor and recipient mice of the aGVHD model,respectively.Bone marrow transplantation(BMT)mouse model(n=20)was established by being injected with bone marrow cells(1 × 10'per mouse)from donor mice within 4-6 hours after receiving a lethal dose(8.0 Gy,72.76 cGy/min)of y ray general irradiation.A mouse model of aGVHD(n=20)was established by infusing a total of 0.4 ml of a mixture of donor mouse-derived bone marrow cells(1 × 107 per mouse)and spleen lymphocytes(2 × 106 per mouse).The blood was removed from the eyeballs and the mouse serum was aspirated on the 7th day after modeling.Bone marrow-derived MSCs were isolated from 1-week-old C57BL/6N male mice and incubated with 2％,5％and 10％BMT mouse serum and aGVHD mouse serum in the medium,respectively.The effect of serum in the two groups on the in vitro adipogenic differentiation ability of mouse MSCs was detected by Oil Red O staining.The expression levels of related proteins PPARy and CEBPα were detected by Western blot.The expression differences of key adipogenic transcription factors including PPARy,CEBPα,FABP4 and LPL were determined by real-time quantitative PCR(RT-qPCR).Results:An in vitro cell model simulating the damage of bone marrow microenvironment in mice with aGVHD was successfully established.Oil Red O staining showed that the number of orange-red fatty droplets was significantly reduced and the adipogenic differentiation ability of MSC was impaired at aGVHD serum concentration of 10％compared with BMT serum.Western blot experiments showed that adipogenesis-related proteins PPARy and CEBPα expressed in MSCs were down-regulated.Further RT-qPCR assay showed that the production of PPARy,CEBPα,FABP4 and LPL,the key transcription factors for adipogenic differentiation of MSC,were significantly reduced.Conclusion:The adipogenic differentiation capacity of MSCs is inhibited by aGVHD mouse serum.

Humans ; Aged ; Hip Fractures/surgery* ; Treatment Outcome

Objective: To assess the efficacy and safety of polymyxin B in neutropenic patients with hematologic disorders who had refractory gram-negative bacterial bloodstream infection. Methods: From August 2021 to July 2022, we retrospectively analyzed neutropenic patients with refractory gram-negative bacterial bloodstream infection who were treated with polymyxin B in the Department of Hematology of the First Affiliated Hospital of the Soochow University between August 2021 to July 2022. The cumulative response rate was then computed. Results: The study included 27 neutropenic patients with refractory gram-negative bacterial bloodstream infections. Polymyxin B therapy was effective in 22 of 27 patients. The median time between the onset of fever and the delivery of polymyxin B was 3 days [interquartile range (IQR) : 2-5]. The median duration of polymyxin B treatment was 7 days (IQR: 5-11). Polymyxin B therapy had a median antipyretic time of 37 h (IQR: 32-70). The incidence of acute renal dysfunction was 14.8% (four out of 27 cases), all classified as "injury" according to RIFLE criteria. The incidence of hyperpigmentation was 59.3%. Conclusion: Polymyxin B is a viable treatment option for granulocytopenia patients with refractory gram-negative bacterial bloodstream infections.
Humans ; Polymyxin B/adverse effects* ; Retrospective Studies ; Gram-Negative Bacterial Infections/complications* ; Fever/drug therapy* ; Sepsis/drug therapy* ; Anti-Bacterial Agents/therapeutic use* ; Bacteremia/complications*

Objective: To analyze the short-term effect of individual atmospheric PM_2.5 exposure on the diversity, enterotype, and community structure of gut microbiome in healthy elderly people in Jinan, Shandong province. Methods: The present panel study recruited 76 healthy elderly people aged 60-69 years old in Dianliu Street, Lixia District, Jinan, Shandong Province, and followed them up five times from September 2018 to January 2019. The relevant information was collected by questionnaire, physical examination, precise monitoring of individual PM_2.5 exposure, fecal sample collection and gut microbiome 16S rDNA sequencing. The Dirichlet multinomial mixtures (DMM) model was used to analyze the enterotype. Linear mixed effect model and generalized linear mixed effect model were used to analyze the effect of PM_2.5 exposure on gut microbiome α diversity indices (Shannon, Simpson, Chao1, and ACE indices), enterotype and abundance of core species. Results: Each of the 76 subjects participated in at least two follow-up visits, resulting in a total of 352 person-visits. The age of 76 subjects was (65.0±2.8) years old with BMI (25.0±2.4) kg/m². There were 38 males accounting for 50% of the subjects. People with an educational level of primary school or below accounted for 10.5% of the 76 subjects, and those with secondary school and junior college or above accounting for 71.1% and 18.4%. The individual PM_2.5 exposure concentration of 76 subjects during the study period was (58.7±53.7) μg/m³. DMM model showed that the subjects could be divided into four enterotypes, which were mainly driven by Bacteroides, Faecalibacterium, Lachnospiraceae, Prevotellaceae, and Ruminococcaceae. Linear mixed effects model showed that different lag periods of PM_2.5 exposure were significantly associated with a lower gut α diversity index (FDR<0.05 after correction). Further analysis showed that PM_2.5 exposure was significantly associated with changes in the abundances of Firmicutes (Megamonas, Blautia, Streptococcus, etc.) and Bacteroidetes (Alistipes) (FDR<0.05 after correction). Conclusion: Short-term PM_2.5 exposure is significantly associated with a decrease in gut microbiome diversity and changes in the abundance of several species of Firmicutes and Bacteroidetes in the elderly. It is necessary to further explore the underlying mechanisms between PM_2.5 exposure and the gut microbiome, so as to provide a scientific basis for promoting the intestinal health of the elderly.
Aged ; Humans ; Male ; Middle Aged ; Feces/microbiology* ; Gastrointestinal Microbiome ; Particulate Matter ; RNA, Ribosomal, 16S/genetics* ; Female

Objective: To investigate the clinical efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with acute leukemia who are positive for the SET-NUP214 fusion gene (SET-NUP214⁺AL). Methods: This was a retrospective case series study. Clinical data of 18 patients with SET-NUP214⁺AL who received allo-HSCT in the First Affiliated Hospital of Soochow University and Soochow Hongci Hematology Hospital from December 2014 to October 2021 were retrospectively analyzed to investigate treatment efficacy and prognosis. The Kaplan-Meier method was used for survival analysis. Results: Of the 18 patients, 12 were male and 6 were female, and the median age was 29 years (range, 13-55 years). There were six cases of mixed phenotype acute leukemia (three cases of myeloid/T, two cases of B/T, one case of myeloid/B/T), nine cases of acute lymphoblastic leukemia (ALL) (one case of B-ALL and eight cases of T-ALL), and three cases of acute myeloid leukemia. All patients received induction chemotherapy after diagnosis, and 17 patients achieved complete remission (CR) after chemotherapy. All patients subsequently received allo-HSCT. Pre-transplantation status: 15 patients were in the first CR, 1 patient was in the second CR, 1 was in partial remission, and 1 patient did not reach CR. All patients were successfully implanted with stem cells. The median time of granulocyte and platelet reconstitution was +12 and +13 days, respectively. With a median follow-up of 23 (4-80) months, 15 patients survived, while 3 patients died. The cause of death was recurrence of SET-NUP214⁺AL after transplantation. After allo-HSCT, 5 patients relapsed. The estimated 3-year overall survival (OS) and relapse-free survival (RFS) rates were 83.3%±15.2% and 55.4%±20.7%, respectively. Among the 15 patients who achieved CR before transplantation, there was no significant difference in OS and RFS between haploidentical HSCT and matched sibling donor HSCT (all P>0.05). Conclusions: Allo-HSCT can improve the prognosis and long-term survival rate of patients with SET-NUP214⁺AL. Disease recurrence is the most important factor affecting long-term survival.
Male ; Female ; Humans ; Retrospective Studies ; Hematopoietic Stem Cell Transplantation/methods* ; Leukemia, Myeloid, Acute/therapy* ; Survival Analysis ; Remission Induction ; Acute Disease ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy* ; Recurrence ; Nuclear Pore Complex Proteins

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.
Adolescent ; Brain Abscess ; Child ; Child, Preschool ; Escherichia coli ; Female ; Humans ; Hydrocephalus ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial/epidemiology* ; Retrospective Studies ; Streptococcus agalactiae ; Streptococcus pneumoniae ; Subdural Effusion ; beta-Lactamases