BACKGROUND:Studies have shown that upregulation of heme oxygenase-1 expression enhances cellular antioxidant and anti-apoptotic abilities.However,the effects of upregulating heme oxygenase-1 expression on the proliferation and differentiation of neural stem cells under oxidative stress conditions remain unclear.OBJECTIVE:To investigate the influence of heme oxygenase-1 overexpression on the survival and differentiation capacity of neural stem cells under oxidative stress conditions.METHODS:(1)Mouse primary neural stem cells were isolated and cultured from newborn Balb/c mice.Immunofluorescence was used to detect the neural stem cell marker Nestin.(2)Lentivirus was used to infect neural stem cells to induce heme oxygenase-1 overexpression.Flow cytometry was used to assess green fluorescent protein fluorescence.Western blot assay was performed to detect the expression levels of heme oxygenase-1.(3)H2O2 was added to the lentivirus-infected neural stem cell culture medium to simulate the oxidative stress microenvironment after spinal cord injury.Effects of heme oxygenase-1 overexpression on neural stem cell proliferation and apoptosis levels were analyzed using cell proliferation assay kits,cell apoptosis assay kits,and TUNEL staining kits.(4)The levels of lipid oxidation markers malondialdehyde,catalase,superoxide dismutase,and glutathione peroxidase were detected using assay kits.(5)Flow cytometry was used to measure intracellular reactive oxygen species levels,and neural stem cell differentiation into astrocytes and neurons.(6)The effect of heme oxygenase-1 overexpression on neuronal axon growth during neural stem cell differentiation was observed under optical and fluorescence microscopes.RESULTS AND CONCLUSION:(1)Mouse neural stem cells exhibited stable morphology,good growth status,and high expression of Nestin as detected by immunofluorescence.(2)Western blot analysis showed that the overexpression of heme oxygenase-1 in the overexpression group was significantly higher than that in the empty carrier control group.Flow cytometry was used to detect the expression of green fluorescent protein in the neural stem cells of the heme oxygenase-1 overexpression group and empty vector control group.(3)Overexpression of heme oxygenase-1 maintained the proliferative activity of neural stem cells and significantly reduced the number of apoptotic cells under oxidative stress conditions.(4)Overexpression of heme oxygenase-1 inhibited lipid peroxidation of neural stem cells under oxidative stress microenvironment,enhanced the expression of enzymes related to maintaining the oxidative-reductive balance,and significantly reduced intracellular reactive oxygen species levels.(5)Overexpression of heme oxygenase-1 promoted the differentiation of neural stem cells into neurons and reduced differentiation into astrocytes.(6)The heme oxygenase-1 overexpression group exhibited longer axons,and more intercellular connections.The above results indicate that overexpression of heme oxygenase-1 can alleviate oxidative damage of H2O2-induced neural stem cells,reduce neural stem cell apoptosis,promote proliferation,and facilitate differentiation of neural stem cells into neurons.

BACKGROUND:Formononetin demonstrates potent anti-inflammatory and antioxidant abilities.However,its protective effect on nucleus pulposus mesenchymal stem cells is not yet clear.OBJECTIVE:To investigate the effect and mechanism of formononetin on nucleus pulposus mesenchymal stem cells under an inflammatory microenvironment.METHODS:(1)Primary nucleus pulposus mesenchymal stem cells were isolated from the intervertebral discs of SD rats,and flow cytometry was performed to identify the surface markers of mesenchymal stem cells.(2)The CCK-8 assay was employed to evaluate the impact of lipopolysaccharide and formononetin on the proliferation viability of nucleus pulposus mesenchymal stem cells,aiming to determine the appropriate concentration of formononetin for subsequent cell treatments.(3)An inflammatory microenvironment was simulated by adding 5 μg/mL lipopolysaccharide to the DMEM/F-12 culture medium,and nucleus pulposus mesenchymal stem cells were treated with different concentrations of formononetin for 24 hours.Levels of inflammation markers were detected using western blot assay,real-time quantitative PCR,and immunofluorescence.Western blot assay was conducted to measure the protein levels of the nuclear factor kappa B signaling pathway.RESULTS AND CONCLUSION:(1)The nucleus pulposus mesenchymal stem cells cultured in adherent wall were shuttle-shaped with good growth status.The results of flow cytometry showed that the surface markers of mesenchymal stem cells were positive for CD29,CD44,and CD90,and the surface markers of hematopoietic stem cells were negative for CD34 and CD45.(2)The treatment with formononetin at 12.5,25,50,100,and 200 μmol/L concentrations for 24 hours had no significant proliferation inhibitory effect on nucleus pulposus mesenchymal stem cells.Compared with the lipopolysaccharide group,the cell viability of nucleus pulposus mesenchymal stem cells treated with 12.5,25,and 50 μmol/L formononetin for 24 hours was significantly increased,so formononetin at 12.5,25,and 50 μmol/L concentrations was subsequently selected as the low,medium,and high concentrations for treating nucleus pulposus mesenchymal stem cells.(3)Compared with the lipopolysaccharide group,the protein and mRNA expressions of matrix metalloproteinase-3,matrix metalloproteinase-13,and tumor necrosis factor-α in nucleus pulposus mesenchymal stem cells in the low,medium,and high concentrations of formononetin groups were significantly decreased(P＜0.05)in a dose-dependent manner.(4)Compared with the lipopolysaccharide group,the expressions of phosphorylated nuclear factor kappa B and phosphorylated nuclear factor kappa B inhibitor protein in nucleus pulposus mesenchymal stem cells in the low,medium,and high concentrations of formononetin groups were significantly decreased(P＜0.05)in a dose-dependent manner.The above results suggest that formononetin may attenuate lipopolysaccharide-induced inflammation in rat nucleus pulposus mesenchymal stem cells by inhibiting the activation of the nuclear factor kappa B signaling pathway.

BACKGROUND:Formononetin demonstrates potent anti-inflammatory and antioxidant abilities.However,its protective effect on nucleus pulposus mesenchymal stem cells is not yet clear.OBJECTIVE:To investigate the effect and mechanism of formononetin on nucleus pulposus mesenchymal stem cells under an inflammatory microenvironment.METHODS:(1)Primary nucleus pulposus mesenchymal stem cells were isolated from the intervertebral discs of SD rats,and flow cytometry was performed to identify the surface markers of mesenchymal stem cells.(2)The CCK-8 assay was employed to evaluate the impact of lipopolysaccharide and formononetin on the proliferation viability of nucleus pulposus mesenchymal stem cells,aiming to determine the appropriate concentration of formononetin for subsequent cell treatments.(3)An inflammatory microenvironment was simulated by adding 5 μg/mL lipopolysaccharide to the DMEM/F-12 culture medium,and nucleus pulposus mesenchymal stem cells were treated with different concentrations of formononetin for 24 hours.Levels of inflammation markers were detected using western blot assay,real-time quantitative PCR,and immunofluorescence.Western blot assay was conducted to measure the protein levels of the nuclear factor kappa B signaling pathway.RESULTS AND CONCLUSION:(1)The nucleus pulposus mesenchymal stem cells cultured in adherent wall were shuttle-shaped with good growth status.The results of flow cytometry showed that the surface markers of mesenchymal stem cells were positive for CD29,CD44,and CD90,and the surface markers of hematopoietic stem cells were negative for CD34 and CD45.(2)The treatment with formononetin at 12.5,25,50,100,and 200 μmol/L concentrations for 24 hours had no significant proliferation inhibitory effect on nucleus pulposus mesenchymal stem cells.Compared with the lipopolysaccharide group,the cell viability of nucleus pulposus mesenchymal stem cells treated with 12.5,25,and 50 μmol/L formononetin for 24 hours was significantly increased,so formononetin at 12.5,25,and 50 μmol/L concentrations was subsequently selected as the low,medium,and high concentrations for treating nucleus pulposus mesenchymal stem cells.(3)Compared with the lipopolysaccharide group,the protein and mRNA expressions of matrix metalloproteinase-3,matrix metalloproteinase-13,and tumor necrosis factor-α in nucleus pulposus mesenchymal stem cells in the low,medium,and high concentrations of formononetin groups were significantly decreased(P＜0.05)in a dose-dependent manner.(4)Compared with the lipopolysaccharide group,the expressions of phosphorylated nuclear factor kappa B and phosphorylated nuclear factor kappa B inhibitor protein in nucleus pulposus mesenchymal stem cells in the low,medium,and high concentrations of formononetin groups were significantly decreased(P＜0.05)in a dose-dependent manner.The above results suggest that formononetin may attenuate lipopolysaccharide-induced inflammation in rat nucleus pulposus mesenchymal stem cells by inhibiting the activation of the nuclear factor kappa B signaling pathway.

BACKGROUND:Studies have shown that upregulation of heme oxygenase-1 expression enhances cellular antioxidant and anti-apoptotic abilities.However,the effects of upregulating heme oxygenase-1 expression on the proliferation and differentiation of neural stem cells under oxidative stress conditions remain unclear.OBJECTIVE:To investigate the influence of heme oxygenase-1 overexpression on the survival and differentiation capacity of neural stem cells under oxidative stress conditions.METHODS:(1)Mouse primary neural stem cells were isolated and cultured from newborn Balb/c mice.Immunofluorescence was used to detect the neural stem cell marker Nestin.(2)Lentivirus was used to infect neural stem cells to induce heme oxygenase-1 overexpression.Flow cytometry was used to assess green fluorescent protein fluorescence.Western blot assay was performed to detect the expression levels of heme oxygenase-1.(3)H2O2 was added to the lentivirus-infected neural stem cell culture medium to simulate the oxidative stress microenvironment after spinal cord injury.Effects of heme oxygenase-1 overexpression on neural stem cell proliferation and apoptosis levels were analyzed using cell proliferation assay kits,cell apoptosis assay kits,and TUNEL staining kits.(4)The levels of lipid oxidation markers malondialdehyde,catalase,superoxide dismutase,and glutathione peroxidase were detected using assay kits.(5)Flow cytometry was used to measure intracellular reactive oxygen species levels,and neural stem cell differentiation into astrocytes and neurons.(6)The effect of heme oxygenase-1 overexpression on neuronal axon growth during neural stem cell differentiation was observed under optical and fluorescence microscopes.RESULTS AND CONCLUSION:(1)Mouse neural stem cells exhibited stable morphology,good growth status,and high expression of Nestin as detected by immunofluorescence.(2)Western blot analysis showed that the overexpression of heme oxygenase-1 in the overexpression group was significantly higher than that in the empty carrier control group.Flow cytometry was used to detect the expression of green fluorescent protein in the neural stem cells of the heme oxygenase-1 overexpression group and empty vector control group.(3)Overexpression of heme oxygenase-1 maintained the proliferative activity of neural stem cells and significantly reduced the number of apoptotic cells under oxidative stress conditions.(4)Overexpression of heme oxygenase-1 inhibited lipid peroxidation of neural stem cells under oxidative stress microenvironment,enhanced the expression of enzymes related to maintaining the oxidative-reductive balance,and significantly reduced intracellular reactive oxygen species levels.(5)Overexpression of heme oxygenase-1 promoted the differentiation of neural stem cells into neurons and reduced differentiation into astrocytes.(6)The heme oxygenase-1 overexpression group exhibited longer axons,and more intercellular connections.The above results indicate that overexpression of heme oxygenase-1 can alleviate oxidative damage of H2O2-induced neural stem cells,reduce neural stem cell apoptosis,promote proliferation,and facilitate differentiation of neural stem cells into neurons.

Objective:To explore the distribution characteristics and antibiotic resistance of pathogen in children with hematological disorders and cancers complicated with sepsis in pediatric intensive care unit (PICU).Methods:The clinical data of children with hematological disorders and cancers complicated with sepsis hospitalized at Shenzhen Children′s Hospital affiliated to China Medical University from January 2016 to August 2023 were retrospectively analyzed. Patients were divided into survival group and death group based on the outcome of sepsis on 28 days after diagnosis.Results:A total of 202 sepsis episodes occurred in 176 children were enrolled in this study. Among all, 144 (71.3%) cases of bloodstream infection, 59 (29.2%) cases of pulmonary infection, 21 (10.4%) cases of abdominal infection, 9 (4.5%) cases of soft tissue infection, 9 (4.5%) cases of nervous system infection, and 3 (1.5%) cases of urinary tract infection. A total of 244 pathogenic strains were identified, in which 74 (30.3%) cases were gram-positive bacteria. The top 3 pathogens isolated were Coagulase negative Staphylococcus (21 strains), Staphylococcus aureus (19 strains) and Streptococcus pneumoniae (13 strains). Gram-negative bacteria accounted for 122 (50.0%) strains, in which top 3 were Klebsiella pneumonia (33 strains), Escherichia coli (25 strains), and Pseudomonas aeruginosa (23 strains). Fungi comprised 48 (19.7%) strains:the top 3 were Candida tropicalis (14 strains), Candida albicans (10 strains), Aspergillus and Pneumocystis jirovecii (7 strains each). The incidence of Acinetobacter baumannii, Stenotrophomonas maltophilia, and Pseudomonas aeruginosa were significantly higher in death group compared to survival group[9.0%（6/67）vs. 2.3%（4/177）, χ2＝3.971 ，P＝0.046; 9.0%（6/67）vs. 1.1%（2/177）, χ2＝7.080 ，P＝0.008;16.4%（11/67）vs. 6.8%（12/177）, χ2＝5.288 ，P＝0.021]. The samples of 57 cases were simultaneously detected by both culture and metagenomic next-generation sequencing (mNGS). Pathogens were detected in 25 cases by both culture and mNGS. In 30 cases, pathogen detection were mNGS positive but culture negative. Two cases showed positive results only with culture. A total of 79 (46.8%) strains were multi-drug resistant bacteria, including 27 (34.2%) strains of gram-positive bacteria and 52 (65.8%) strains of gram-negative bacteria. A total of 174 (86.1%) children with sepsis received empirical anti-infective drugs within 24 hours of fever onset. A total of 124 (61.4%) cases were appropriately covered by the initial empirical antibiotics, while 40 (19.8%) cases were not adequately covered and 10 (5.0%) cases had incomplete coverage. Despite the inclusion of pathogenic in the coverage, resistance to initial antibiotics was observed in 22 (10.9%) cases. Fifty-one patients died. Conclusion:The predominant pathogens responsible for sepsis in PICU with hematological disorders and cancers is gram-negative bacteria, followed by gram-positive bacteria and fungi. In comparison to healthy children with sepsis, there is a higher incidence of fungal infections among hematological disorders and cancers. The proportion of multi-drug resistant bacteria infection is high. Early identification and combination of local etiological distribution and drug resistance, along with the empirical selection of appropriate anti-infection treatment strategies, can greatly enhance survival rate.

OBJECTIVE: To observe the effects of electroacupuncture (EA) pretreatment on cardiac function, sympathetic nerve activity, indexes of myocardial injury and GABA_A receptor in fastigial nucleus in rats with myocardial ischemia reperfusion injury (MIRI), and to explore the neuroregulatory mechanism of EA pretreatment in improving MIRI. METHODS: A total of 60 male SD rats were randomly divided into a sham operation group, a model group, an EA group, an agonist group and an agonist+EA group, 12 rats in each group. The MIRI model was established by ligation of the left anterior descending coronary artery. EA was applied at bilateral "Shenmen" (HT 7) and "Tongli" (HT 5) in the EA group and the agonist+EA group, with continuous wave, in frequency of 2 Hz and intensity of 1 mA, 30 min each time, once a day for 7 consecutive days. After intervention, the MIRI model was established. In the agonist group, the muscone (agonist of GABA_A receptor, 1 g/L) was injected in fastigial nucleus for 7 consecutive days before modeling, 150 μL each time, once a day. In the agonist+EA group, the muscone was injected in fastigial nucleus 30 min before EA intervention. The data of electrocardiogram was collected by PowerLab standard Ⅱ lead, and ST segment displacement and heart rate variability (HRV) were analyzed; the serum levels of norepinephrine (NE), creatine kinase isoenzyme MB (CK-MB) and cardiac troponin I (cTnI) were detected by ELISA; the myocardial infarction area was measured by TTC staining; the morphology of myocardial tissue was observed by HE staining; the positive expression and mRNA expression of GABA_A receptor in fastigial nucleus were detected by immunohistochemistry and real-time PCR. RESULTS: Compared with the sham operation group, in the model group, ST segment displacement and ratio of low frequency to high frequency (LF/HF) of HRV were increased (P<0.01), HRV frequency domain analysis showed enhanced sympathetic nerve excitability, the serum levels of NE, CK-MB and cTnI were increased (P<0.01), the percentage of myocardial infarction area was increased (P<0.01), myocardial fiber was broken and interstitial edema was serious, the positive expression and mRNA expression of GABA_A receptor in fastigial nucleus were increased (P<0.01). Compared with the model group, in the EA group, ST segment displacement and LF/HF ratio were decreased (P<0.01), HRV frequency domain analysis showed reduced sympathetic nerve excitability, the serum levels of NE, CK-MB and cTnI were decreased (P<0.01), the percentage of myocardial infarction area was decreased (P<0.01), myocardial fiber breakage and interstitial edema were lightened, the positive expression and mRNA expression of GABA_A receptor in fastigial nucleus were decreased (P<0.01). Compared with the EA group, in the agonist group and the agonist+EA group, ST segment displacement and LF/HF ratio were increased (P<0.01), HRV frequency domain analysis showed enhanced sympathetic nerve excitability, the serum levels of NE, CK-MB and cTnI were increased (P<0.01), the percentage of myocardial infarction area was increased (P<0.01), myocardial fiber breakage and interstitial edema were aggravated, the positive expression and mRNA expression of GABA_A receptor in fastigial nucleus were increased (P<0.01). CONCLUSION EA pretreatment can improve the myocardial injury in MIRI rats, and its mechanism may be related to the inhibition of GABA_A receptor expression in fastigial nucleus, thereby down-regulating the excitability of sympathetic nerve.
Male ; Animals ; Rats ; Rats, Sprague-Dawley ; Cerebellar Nuclei ; Electroacupuncture ; Myocardial Reperfusion Injury/therapy* ; Receptors, GABA-A/genetics* ; RNA, Messenger

Humans ; Pyroptosis/physiology* ; Pore Forming Cytotoxic Proteins

Aim To investigate the curative effects of resveratrol on OVA induced allergic rhinitis in mice and the underlying immune mechanisms. Methods Balb/c mice (female, 6 weeks) were divided randomly into normal control ( NC) group, allergic rhinitis (AR) group, high dose resveratrol treatment group (RH), low dose resveratrol treatment group (RL), and dexamethasone treatment group ( Dex). RL, RH and Dex group were oral administered with resveratrol 30 mg • kg"1, resveratrol 100 mg • kg"1 and dexamethasone 10 mg • kg"1, respectively. After the treat-ment , the sneezing and nasal rubbing behaviors of mice in all the group were recorded and HE was performed to assess the inflammatory cell infiltration in nasal tissues. The sera levels of allergic cytokines were determined with ELISA assay. The percentage of CD4+ GA- TA3 + T cells in spleen of each group was further recorded by flow cytometry. Results Compared with AR group, treatment with resveratrol (100 mg - kg"1) reduced the sneezing and nasal rubbing behaviors signifi-cantly and improved inflammatory cell infiltration in nasal tissues. The up-regulated sera levels of IL-4, IL- 13 and OVA-sIgE in AR group were reversed by RH, and ratios CD4+ GATA3 + Th2 cells in spleen of RH were also down-regulated parallelly. Conclusions RH treatment could improve the allergic related symptoms of OVA-induced allergic rhinitis, which is associated with down-regulated sera levels of IL-4, IL-13 and OVA-sIgE and ratios of CD4+ GATA3 + Th2 cells in spleen of mouse model.

Acclimatization ; physiology ; Altitude ; Altitude Sickness ; prevention & control ; Humans ; Hypoxia ; physiopathology ; Male ; Military Personnel ; Mountaineering ; physiology ; Oxygen Consumption ; physiology ; Physical Fitness ; physiology ; Young Adult

Cytomegalovirus infection (CMV-I) and CMV related diseases (CMV-D) occurred after allogeneic hematopoietic stem cell transplantation (Allo-HSCT) seem to be with high morbidity and mortality. This study is a retrospective analysis of the incidence of CMV infection and diseases in Allo-HSCT patients known to be CMV seropositive before transplantation. To review the efficacy of CMV pp65 antigen-guided ganciclovir prophylaxis in preventing CMV infection and to search the optimal determination methods, 45 consecutive Allo-HSCT patients have been observed. Using the CMV pp65 antigenemia assay and serological analysis monitored blood samples from 23 patients with chronic myeloid leukemia (CML), 7 acute myeloblastic leukemia (AML), 6 acute lymphoblastic leukemia (ALL); other: 4 myelodysplastic syndrome (MDS), 3 non-Hodgkin's lymphoma (NHL) and 2 aplastic anemia. Forty-three patients received HLA-identical siblings transplantation and 2 from their HLA-haploidentical donors. Forty-five cases included Allo-PBPCT (38 cases), Allo-BMT (2 cases) and Allo-PBPCT + BMT 5 cases. Before transplantation, all donors/recipients have taken CMV serological detection. All donor/recipients were CMV IgG positive and one donor and one recipient with CMV IgM positive, respectively. After transplantation, all patients developed CMV antigenemia during monitoring period. Twenty-five patients developed CMV related interstitial pneumonia (CMV-IP). Patients have been followed from 6 to 28 months (median of 18 months) after transplantation. The patients who received preemptive therapy had a significantly better outcome than patients who did not received preemptive therapy. CMV related mortality was 1/29 cases in preemptive group vs. 12/16 cases in non-preemptive group. The results suggest that prompt and early institution of effective therapy with ganciclovir upon detection of CMV pp65 antigenemia, provides optimal protection against progress of CMV disease for patients undergoing Allo-HSCT.