Objective:To investigate the effect and preliminary mechanism of hypervirulent Klebsiella pneumoniae (hvKP) on the immune response to sepsis induced by liver abscess in mice. Methods:C57BL/6 mice were intraperitoneally injected with hvKP strain NTUH-K2044 or classical Klebsiella pneumoniae (cKP) strain HS11286 suspension to prepare the model of sepsis. The survivals rates of mice within 24 h were recorded. HE staining was used to observed the inflammatory cell infiltration in mouse liver tissues. The levels of neutrophil marker lymphocyte antigen 6G (Ly6G) in mouse liver tissues were detected by immunohistochemistry. The activity of reactive oxygen species (ROS) in mouse liver macrophages and peripheral blood monocytes was measured by ROS assay kit. The activation of p105/p50 and p65 in NF-κB signaling pathway in mouse liver macrophages and peripheral blood monocytes was detected by Western blot. The expression of IL-1β, IL-6 and TNF-α at mRNA and protein levels in mouse liver macrophages and peripheral blood monocytes were detected by qRT-PCR and ELISA, respectively. One-way analysis of variance and t test were used for statistical analysis. Results:Compared with cKP, hvKP infection could induce C57BL/6 mice to develop obvious liver abscess with massive inflammatory cell infiltration. Moreover, the level of Ly6G in liver tissues was significantly higher in hvKP-infected mice than in cKP-infected mice ( P<0.000 1), but the survival rate of hvKP-infected mice was significantly lower than that of cKP-infected mice ( P<0.000 1). hvKP significantly promoted the ROS activity ( P<0.000 1) and enhanced the phosphorylation of p105/p50 and p65 in NF-κB signaling pathway in mouse liver macrophages and peripheral blood monocytes as compared with cKP ( P<0.001). The expression of IL-1β, IL-6 and TNF-α at mRNA and protein levels in mouse liver macrophages and peripheral blood monocytes were significantly higher in hvKP-infected mice than in cKP-infected mice ( P<0.001). Conclusion:hvKP can promote the development of liver abscess and induce sepsis in mice.

Objective:To investigate the role of TcpC, a virulence factor of uropathogenic Escherichia coli (UPEC), in inhibiting the formation of neutrophil extracellular traps (NETs) in mouse bone marrow neutrophils, and to analyze its pathogenic mechanism. Methods:C57BL/6 mice were injected with either wild-type (CFT073 wt) or tcpc gene-knockout UPEC CFT073(CFT073 Δ tcpc) to establish a mouse model of cystitis. Mice were sacrificed 3 d post-infection, and their bladders were collected to observe gross pathological changes. Hematoxylin-eosin (HE) staining was used to assess histopathological changes in bladder tissues, and immunohistochemistry was performed to localize TcpC in bladder tissues. Bacterial loads in urine samples were quantified using the ten-fold dilution method, and the presence of tcpc gene in genomic DNA from bladder or urine samples was confirmed by PCR. The expression of TcpC at mRNA and protein levels in mouse bone marrow nuetrophils infected with CFT073 wt was detected by qRT-PCR and Western blot. The effects of UPEC infection on expression of NETs-related proteins and the production of pro-inflammatory factors in mouse bone marrow neutrophils were analyzed by Western blot and ELISA, respectively. Reactive oxygen species(ROS) level and bacterial viability in mouse bone marrow nuetrophils were measured using ROS and bacterial viability detection kits. Results:Compared to the CFT073 Δ tcpc group, the bladder of CFT073 wt group mice exhibited significant enlargement, extensive inflammatory cell infiltration, and the presence of TcpC in bladder tissue. The bacterial load in the urine of CFT073 wt -infected mice was significantly higher than that in the CFT073 Δ tcpc group ( P<0.01). PCR confirmed the presence of the tcpc gene in bladder and urine samples from CFT073 wt-infected mice. Increased expression of TcpC at both mRNA and protein levels was observed in CFT073 wt-infected mouse bone marrow neutrophils. CFT073 wt infection inhibited the mRNA and protein expression of NETs-related proteins and reduced the production of pro-inflammatory factors in mouse bone marrow neutrophils. TcpC suppressed ROS level and promoted the survival of CFT073 wt in mouse bone marrow neutrophils. Conclusions:TcpC enhances the pathogenicity of UPEC CFT073 by inhibiting the formation and activation of NETs in mouse bone marrow neutrophils. This study provides new insights into the pathogenic mechanisms of UPEC and the immune evasion strategies of other pathogenic bacteria, as well as potential targets for clinical prevention and treatment of UPEC-induced urinary tract infections.

Objective To investigate if Shikonin(SKI)can induce ferroptosis via the ROS/JNK pathway to inhibit the malignant behavior of pancreatic cancer.Methods Human pancreatic cancer PANC-1 or BxPC-3 cells were selected.Drug efficacy experiments were established with a blank control group(Con group)and low,medium,and high dose SKI groups(2,4,8 μmol/L).JNK-related mechanism experiments were categorized into a blank control group(Con group),SKI group,and SKI+JNK inhibitor group(SKI+SP600125 group).ROS-related mechanism experiments were divided into a blank control group(Con group),SKI group,and SKI+ROS scavenger group(SKI+NAC group).Cell viability was assessed using the CCK-8 method to calculate IC50;Transwell experiments evaluated cell migration and invasion capabilities;the C11 BODIPY 581/591 probe was utilized for flow cytometry to detect lipid peroxidation levels,while the FerroOrange fluorescent probe measured ferrous ion levels;ROS levels were determined using a ROS detection kit;the Western blot method identified ferroptosis-related key proteins(SLC7A11,GPX4),apoptosis-related proteins(Caspase3,PARP),and JNK pathway proteins(JNK,p-JNK);an in vivo xenograft tumor model was employed to assess tumor proliferation.Results SKI treatment significantly and dose-dependently inhibited PANC-1 cell viability(IC50:6.04 μmol/L,P<0.0001)and BxPC-3 cell viability(IC50:12.27 μmol/L,P<0.0001),and significantly reduced migrating and invasive cell numbers(P<0.0001),with migration cell numbers dropping to about 30%of the control group at 8 μmol/L SKI treatment(P<0.0001).Mechanistically,SKI induced increased intracellular lipid peroxidation,Fe2+accumulation,and significant ROS production(P<0.0001),significantly downregulated SLC7A11 and GPX4 protein expression(GPX4 protein expression reduced to 40%of that in the control group,P<0.0001),and activated JNK phosphorylation(p-JNK/JNK ratio increased to 2.8-fold,P<0.0001).Pretreatment with the JNK-specific inhibitor SP600125 or ROS scavenger NAC effectively reversed SKI's inhibition of cell viability and downregulation of SLC7A11/GPX4 protein(all P<0.01).SKI also inhibited pancreatic cancer tumor cell proliferation in vivo(P<0.0001).Conclusion SKI induces ferroptosis by activating the ROS/JNK pathway,thereby inhibiting pancreatic cancer proliferation,migration,and invasion.

Objective:To investigate the effect and preliminary mechanism of hypervirulent Klebsiella pneumoniae (hvKP) on the immune response to sepsis induced by liver abscess in mice. Methods:C57BL/6 mice were intraperitoneally injected with hvKP strain NTUH-K2044 or classical Klebsiella pneumoniae (cKP) strain HS11286 suspension to prepare the model of sepsis. The survivals rates of mice within 24 h were recorded. HE staining was used to observed the inflammatory cell infiltration in mouse liver tissues. The levels of neutrophil marker lymphocyte antigen 6G (Ly6G) in mouse liver tissues were detected by immunohistochemistry. The activity of reactive oxygen species (ROS) in mouse liver macrophages and peripheral blood monocytes was measured by ROS assay kit. The activation of p105/p50 and p65 in NF-κB signaling pathway in mouse liver macrophages and peripheral blood monocytes was detected by Western blot. The expression of IL-1β, IL-6 and TNF-α at mRNA and protein levels in mouse liver macrophages and peripheral blood monocytes were detected by qRT-PCR and ELISA, respectively. One-way analysis of variance and t test were used for statistical analysis. Results:Compared with cKP, hvKP infection could induce C57BL/6 mice to develop obvious liver abscess with massive inflammatory cell infiltration. Moreover, the level of Ly6G in liver tissues was significantly higher in hvKP-infected mice than in cKP-infected mice ( P<0.000 1), but the survival rate of hvKP-infected mice was significantly lower than that of cKP-infected mice ( P<0.000 1). hvKP significantly promoted the ROS activity ( P<0.000 1) and enhanced the phosphorylation of p105/p50 and p65 in NF-κB signaling pathway in mouse liver macrophages and peripheral blood monocytes as compared with cKP ( P<0.001). The expression of IL-1β, IL-6 and TNF-α at mRNA and protein levels in mouse liver macrophages and peripheral blood monocytes were significantly higher in hvKP-infected mice than in cKP-infected mice ( P<0.001). Conclusion:hvKP can promote the development of liver abscess and induce sepsis in mice.

Objective:To investigate the role of TcpC, a virulence factor of uropathogenic Escherichia coli (UPEC), in inhibiting the formation of neutrophil extracellular traps (NETs) in mouse bone marrow neutrophils, and to analyze its pathogenic mechanism. Methods:C57BL/6 mice were injected with either wild-type (CFT073 wt) or tcpc gene-knockout UPEC CFT073(CFT073 Δ tcpc) to establish a mouse model of cystitis. Mice were sacrificed 3 d post-infection, and their bladders were collected to observe gross pathological changes. Hematoxylin-eosin (HE) staining was used to assess histopathological changes in bladder tissues, and immunohistochemistry was performed to localize TcpC in bladder tissues. Bacterial loads in urine samples were quantified using the ten-fold dilution method, and the presence of tcpc gene in genomic DNA from bladder or urine samples was confirmed by PCR. The expression of TcpC at mRNA and protein levels in mouse bone marrow nuetrophils infected with CFT073 wt was detected by qRT-PCR and Western blot. The effects of UPEC infection on expression of NETs-related proteins and the production of pro-inflammatory factors in mouse bone marrow neutrophils were analyzed by Western blot and ELISA, respectively. Reactive oxygen species(ROS) level and bacterial viability in mouse bone marrow nuetrophils were measured using ROS and bacterial viability detection kits. Results:Compared to the CFT073 Δ tcpc group, the bladder of CFT073 wt group mice exhibited significant enlargement, extensive inflammatory cell infiltration, and the presence of TcpC in bladder tissue. The bacterial load in the urine of CFT073 wt -infected mice was significantly higher than that in the CFT073 Δ tcpc group ( P<0.01). PCR confirmed the presence of the tcpc gene in bladder and urine samples from CFT073 wt-infected mice. Increased expression of TcpC at both mRNA and protein levels was observed in CFT073 wt-infected mouse bone marrow neutrophils. CFT073 wt infection inhibited the mRNA and protein expression of NETs-related proteins and reduced the production of pro-inflammatory factors in mouse bone marrow neutrophils. TcpC suppressed ROS level and promoted the survival of CFT073 wt in mouse bone marrow neutrophils. Conclusions:TcpC enhances the pathogenicity of UPEC CFT073 by inhibiting the formation and activation of NETs in mouse bone marrow neutrophils. This study provides new insights into the pathogenic mechanisms of UPEC and the immune evasion strategies of other pathogenic bacteria, as well as potential targets for clinical prevention and treatment of UPEC-induced urinary tract infections.

Objective:To investigate the role of TcpC, a virulence factor of uropathogenic Escherichia coli (UPEC), in immune evasion, and analyze its related pathogenic mechanism. Methods:C57BL/6 mice were injected with 10 9 colony-forming unit of wild-type (CFT073 wt) or tcpc gene-knockout (CFT073 Δ tcpc) UPEC CFT073 strains from urethra into bladder to construct a mouse model of pyelonephritis. These mice were sacrificed 5 d after infection and their kidneys were taken to observe the gross pathological changes. Hematoxylin-eosin staining was used to observe histopathological changes in kidney tissues and immunohistochemistry was performed to locate TcpC in kidney tissues. The bacterial loads in urine samples of UPEC infected-mice were counted by ten-fold dilution method, and the presence of tcpc gene in the genomic DNA of bacteria from CFT073-infected mouse kidney or urine samples was measured by PCR. The expression of TcpC at mRNA level was detected by qRT-PCR after infecting dendritic cells with CFT073 wt strains. The influences of UPEC infection on the activation of NF-κB signaling pathway and the secretion of proinflammatory factors by dendritic cells were analyzed by Western blot and ELISA, respectively. The viability of UPEC strains in dendritic cells were observed by laser confocal microscope. Results:Compared with the CFT073 Δ tcpc group, the mice in the CFT073 wt group had obvious abscess in the kidneys as well as massive neutrophil infiltration and abundant TcpC in kidney tissues. The bacterial loads in the urine of CFT073 wt-infected mice were significantly higher than those in the urine of CFT073 Δ tcpc mice. PCR results showed that tcpc gene was successfully amplified from mouse kidney and urine samples. Increased expression of TcpC at both mRNA and protein levels was detected in CFT073 wt-infected dendritic cells. CFT073 wt infection inhibited the phosphorylation of NF-κB p50 and the production of proinflammatory factors in dendritic cells. TcpC promoted the survival of CFT073 wt in dendritic cells. Conclusions:TcpC expression increases significantly during CFT073 wt infection or in mice with CFT073 wt-induced pyelonephritis. It promotes the survival of CFT073 wt in dendritic cells by inhibiting the activation of NF-κB signaling pathway and reducing the secretion of pro-inflammatory cytokines. TcpC is involved in the pathogenesis of UPEC and immune evasion.

Objective To investigate the effect and mechanism of shikonin on the proliferation,migration,invasion and apoptosis of human gastric cancer MGC803 cells.Methods The MGC803 cells in the logarithmic growth phase were randomly divided into the blank control group,shikonin group,shikonin+insulin-like growth factor-1(IGF-1)group,and shikonin+LY294002 group.Cells in the blank control group were cultured in drug-free medium,cells in the shikonin group were cultured in the medium containing shikonin with a final concentration of 10 μmol·L-1,cells in the shikonin+IGF-1 group were cultured in the medium containing shikonin with a final concentration of 10 μmol·L-1 and IGF-1 with a final concentration of 10 μmol·L-1,and cells in the shikonin+LY294002 group were cultured in the medium containing shikonin with a final concentration of 10 μmol·L-1 and LY294002 with a final concentration of 30 μmol·L-1.After 24 h of culture,the cell proliferation was detected by cell counting kit-8,the cell apoptosis was detected by flow cytometry,the cell migration was detected by scratch assay,and the cell invasion was detected by Transwell assay.The expression levels of B cell lymphoma-2(Bcl-2),Bcl-2 related X protein(Bax),cytochrome C(Cyt C),cleaved caspase-3,cleaved caspase-9,phosphoinositide 3 kinase(PI3K),phosphorylated PI3K(p-PI3K),protein kinase B(PKB),and phosphorylated PKB(p-PKB)proteins were measured by using Western blot.Results The MGC803 cell proliferation inhibition rate and apoptosis rate in the shikonin group were significantly higher than those in the blank control group(P＜0.05);the MGC803 cell proliferation inhibition rate and apoptosis rate in the shikonin+IGF-1 group were significantly lower than those in the shikonin group(P＜0.05);and the MGC803 cell proliferation inhibition rate and apoptosis rate in the shikonin+LY294002 group were significantly higher than those in the shikonin group(P＜0.05).The MGC803 cell scratch healing rate and the number of invasive cells in the shikonin group were significantly lower than those in the blank control group(P＜0.05);the MGC803 cell scratch healing rate and the number of invasive cells in the shikonin+IGF-1 group were significantly higher than those in the shikonin group(P＜0.05);and the MGC803 cell scratch healing rate and the number of invasive cells in the shikonin+LY294002 group were significantly lower than those in the shikonin group(P＜0.05).The relative expression level of Bcl-2 protein in MGC803 cells in the shikonin group was significantly lower than that in the blank control group(P＜0.05),while the relative expression levels of Bax,Cyt C,cleaved caspase-3 and cleaved caspase-9 proteins and the Bax/Bcl-2 ratio were significantly higher than those in the blank control group(P＜0.05);the relative expression level of Bcl-2 protein in MGC803 cells in the shikonin+IGF-1 group was significantly higher than that in the shikonin group(P＜0.05),while the relative expression levels of Bax,Cyt C,cleaved caspase-3 and cleaved caspase-9 proteins and the Bax/Bcl-2 ratio were significantly lower than those in the shikonin group(P＜0.05);and the relative expression level of Bcl-2 protein in MGC803 cells in the shikonin+LY294002 group was significantly lower than that in the shikonin group(P＜0.05),while the relative expression levels of Bax,Cyt C,cleaved caspase-3 and cleaved caspase-9 proteins and the Bax/Bcl-2 ratio were significantly higher than those in the shikonin group(P＜0.05).The relative expression levels of p-PI3K and p-PKB proteins and the ratios of p-PI3K/PI3K and p-PKB/PKB in MGC803 cells in the shikonin group were significantly lower than those in the blank control group(P＜0.05),and there was no statistically significant difference in the relative expression levels of PI3K and PKB proteins in MGC803 cells between the shikonin group and the blank control group(P＞0.05);the relative expression levels of p-PI3K and p-PKB proteins and the ratios of p-PI3K/PI3K and p-PKB/PKB in MGC803 cells in the shikonin+IGF-1 group were significantly higher than those in the shikonin group(P＜0.05),and there was no statistically significant difference in the relative expression levels of PI3K and PKB proteins in MGC803 cells between the shikonin+IGF-1 group and the shikonin group(P＞0.05);and the relative expression levels of p-PI3K and p-PKB proteins and the ratios of p-PI3K/PI3K and p-PKB/PKB in MGC803 cells in the shikonin+LY294002 group were significantly lower than those in the shikonin group(P＜0.05),and there was no statistically significant difference in the relative expression levels of PI3K and PKB proteins in MGC803 cells between the shikonin+LY294002 group and the shikonin group(P＞0.05).Conclusion Shikonin can inhibit the proliferation,migration and invasion and promote the apoptosis of human gastric cancer MGC803 cells,which may be related to its inhibition of the PI3K/PKB signaling pathway.

With an aging population, the incidence of osteoporotic vertebral fractures (OVFs) is on the rise, posing new challenges for developing personalized treatment strategies. For patients who do not respond to conservative treatment, percutaneous vertebroplasty or percutaneous kyphoplasty (PVP/PKP) remains the preferred surgical option due to its minimal invasiveness and rapid recovery time. However, progressive local kyphosis (PLK) is one of the most severe complications following PVP/PKP, with an incidence rate of 1.5%-25.8%. PLK often presents with recurring thoracic and lower back pain, and in severe cases, spinal stenosis, causing symptoms like numbness and pain in the lower limbs. The severity of PLK varies, and treatments can range from conservative management and bone cement reinforcement to internal fixation or osteotomy. Current studies suggest that re-fracture of the affected vertebra, intervertebral disc degeneration, and osteonecrosis may be underlying mechanisms. These conditions shift the axial load forward, promoting postoperative PLK, which tends to progress over time. Postoperative PLK is closely associated with patient characteristics, fracture details, surgical factors, and post-surgery osteoporosis management. 1) The severity of osteoporosis, as indicated by the T-score from bone mineral density testing, can help predict postoperative PLK. While factors like age and gender influence osteoporosis severity, no direct relationship has been established between these factors and PLK. 2) Thoracolumbar fractures, old nonunion fractures, endplate fractures, or severe preoperative compression changes with kyphosis can increase PLK risk. Surgical factors, including the use of balloons or implants and the distribution of bone cement, also play a role. Personalized treatment plans should be developed based on the patient's general condition and imaging results to ensure adequate bone cement diffusion, as enhanced integration can reduce PLK risk. 3) Postoperative anti-osteoporosis therapy is also crucial; long-term therapy, particularly with teriparatide, can prevent PLK. Recognizing the related risk factors and establishing predictive models can help clinicians tailor treatments. Machine learning models, utilizing big data, are particularly adept at handling complex interrelated risk factors and may provide a powerful tool for personalized treatment in the future.

Ex vivo culture-amplified mesenchymal stem cells (MSCs) have been studied because of their capacity for healing tissue injury. MSC transplantation is a valid approach for promoting the repair of damaged tissues and replacement of lost cells or to safeguard surviving cells, but currently the efficiency of MSC transplantation is constrained by the extensive loss of MSCs during the short post-transplantation period. Hence, strategies to increase the efficacy of MSC treatment are urgently needed. Iron overload, reactive oxygen species deposition, and decreased antioxidant capacity suppress the proliferation and regeneration of MSCs, thereby hastening cell death. Notably, oxidative stress (OS) and deficient antioxidant defense induced by iron overload can result in ferroptosis. Ferroptosis may inhibit cell survival after MSC transplantation, thereby reducing clinical efficacy. In this review, we explore the role of ferroptosis in MSC performance. Given that little research has focused on ferroptosis in transplanted MSCs, further study is urgently needed to enhance the in vivo implantation, function, and duration of MSCs.
Humans ; Antioxidants/metabolism* ; Ferroptosis ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stem Cells ; Iron Overload/metabolism*

OBJECTIVE: To review the clinical research progress of spinal epidural lipomatosis (SEL). METHODS: The clinical studies on SEL at home and abroad in recent years were extensively reviewed, and the pathogenesis, clinical and imaging manifestations, and treatment status of SEL were summarized and analyzed. RESULTS: SEL is a disease characterized by compression of the spinal cord and nerve roots due to abnormal accumulation of epidural adipose tissue in the spinal canal. Its prevalence and diagnosis rate are low and the pathogenesis is not fully understood. MRI is the most sensitive and specific diagnostic test for SEL. Surgical decompression and removal of excess adipose tissue are the only options for patients with acute SEL or those who have failed conservative management, and conservative management should be considered for other patients. CONCLUSION SEL is a rare disease and related research still needs to be improved. In the future, high-quality, multi-center and large-sample studies will be of great significance for evaluating the choice of treatment methods and effectiveness of SEL patients.
Humans ; Decompression, Surgical/methods* ; Epidural Space/surgery* ; Lipomatosis/surgery* ; Magnetic Resonance Imaging ; Spinal Cord Diseases/surgery*