Objective To investigate the epidemiological characteristics of cross-county imported dengue fever cases within Yunnan province in 2023, so as to provide insights into formulation of preventive and control measures for intra-provincial spread of dengue fever. Methods All data pertaining cross-county imported dengue fever cases within Yunnan Province in 2023 were collected, and the temporal, regional and population distributions of the cases were descriptively analyzed. Results A total of 1 664 intra-provincial cross-county imported dengue fever cases were reported in 95 counties (cities, districts) cross 16 profectures (cities) in Yunnan Province in 2023, accounting for 12.34% of total cases in the province. Cross-county imported dengue fever cases were predominantly reported during the period between August and October (1 516 cases, 91.11% of total cases), and peaked in September (659 cases), with a single-day peak on October 8 (36 cases). During the period from September 4 to 10, five counties (cities) with local dengue fever epidemics, including Jinghong City of Xishuangbanna Dai Autonomous Prefecture, Gengma Dai and Wa Autonomous County of Lincang City, Ruili City of Dehong Dai and Jingpo Autonomous Prefecture, Mengla Coun ty of Xishuangbanna Dai Autonomous Prefecture, and Zhenkang County of Lincang City, exported 165 cross-county imported dengue fever cases to the rest of the province. Among the 1 644 intra-provincial cross-county imported dengue fever cases, the male to female ratio was 1.40∶1.00, and 1 329 cases were at ages of 15 to 55 years (79.87%), with farmers as the predominant occupation (886 cases, 53.25%). The top 5 counties (cities/districts) reporting the highest number of intra-provincial cross-county imported dengue fever cases included Simao District (266 cases) and Lancang Lahu Autonomous County (118 cases) of Pu’er City, Mengla County (91 cases) and Menghai County (91 cases) of Xishuangbanna Dai Autonomous Prefecture, and Mangshi City (73 cases) of Dehong Dai and Jingpo Autonomous Prefecture, which accounting for 38.40% of total imported cases. These intra-provincial cross-county imported dengue fever cases originated from 7 counties (cities/districts) in 4 prefectures (cities), including 1 261 cases (76.70%) from Jinghong City of Xishuangbanna Dai Autonomous Prefecture, 224 cases (13.63%) from Ruili City of Dehong Dai and Jingpo Autonomous Prefecture, 103 cases (6.27%) from Gengma Dai and Wa Autonomous County of Lincang City, 31 cases (1.89%) from Mengla County of Xishuangbanna Dai Autonomous Prefecture, 30 cases (1.82%) from Zhenkang County of Lincang City, 10 cases (0.61%) from Cangyuan Wa Autonomous County of Lincang City, and 5 cases (0.30%) from Mohan-Boten Economic Cooperation Zone of Kunming City. In addition, local dengue fever epidemics following intra-provincial cross-county importation of dengue fevers cases in Simao District, Jinggu Dai and Yi Autonomous County, Mangshi City, Longchuan County, and Cangyuan Wa Autonomous County. Conclusions Farmers and students are high-risk populations for intra-provincial cross-county imported dengue fever cases in Yunnan Province, and health education pertaining personal protection against dengue fever should be strengthened among these high-risk populations by governments at all levels. There is a high risk of local out-break of dengue fever following continuous introduction of intra-provincial cross-county imported cases. Standardized management of intra-provincial cross-county imported dengue fever cases should be reinforced to reduce the risk of local epidemics.

Objective:To develop a recombinant protein vaccine based on KPC-2, a drug resistance target in Klebsiella pneumoniae, and evaluate its immunogenicity, protective efficacy and mechanism in a mouse model of pneumonia. Methods:KPC-2 was expressed in Escherichia coli and purified using GST affinity chromatography. A recombinant protein vaccine was prepared with KPC-2 and used to immunize New Zealand rabbits through subcutaneous injection. Serum samples were isolated from cardiac blood and Protein G chromatography was used to purify polyclonal antibodies against KPC-2. Opsonophagocytic killing assay was used to assess the bactericidal activity of the polyclonal antibodies in vitro. Female BALB/c mice were immunized three times with the recombinant protein vaccine, and the titers of specific IgG antibodies in serum were measured by indirect ELISA. One week after the last vaccination, the mice were infected with Klebsiella pneumoniae strain SRT through tracheal intubation, and received a single intravenous dose of meropenem (0.1 mg) 1 h later. The protective efficacy of the KPC-2 recombinant protein vaccine was evaluated by comparing the survival rates, bacterial colonization and histopathological changes between vaccine group and adjuvant group as well as the survival rates between meropenem group and normal saline group. Moreover, the protective efficacy of polyclonal antibodies against KPC-2 was evaluated through passive immunization. Results:The level of specific IgG antibodies in serum was significantly higher in the vaccine group than in the adjuvant group ( t=4.325, P<0.05). The survival rate in the vaccine group was also higher than that of the adjuvant group [70% (7/10) vs 10% (1/10), P<0.05]. Furthermore, lung inflammation was less severe and bacterial burden was reduced in the vaccine group as compared with those of the control group ( t=3.127, P<0.05). Both active and passive vaccination strategies demonstrated strong protective efficacy against Klebsiella pneumoniae infection, and had a synergistic effect when used in combination with antibiotic therapy. The polyclonal antibodies against KPC-2 had bactericidal activity in vitro ( t=5.427, P<0.05). Conclusions:The prepared KPC-2 vaccine has better immunogenicity and protective efficacy. It can induce strong humoral immune responses. This study suggest that drug resistance target may be used as a candidate antigen for future vaccine development.

Objective:To evaluate the impact of three small compounds, namely sodium diethyldithiocarbamate (DTC), levamisole (LMS) and imiquimod (Imi), on the immunogenicity and protective efficacy of the candidate antigen PA0833 from Pseudomonas aeruginosa ( Pa) and analyze the underlying mechanisms. Methods:PA0833 was formulated with aluminum adjuvant and the above small compounds, respectively. BALB/c mice were immunized with these vaccines intramuscularly on days 0, 14 and 21. Serum samples were collected and the levels of PA0833-specific IgG were measured by ELISA. The protective efficacy of these vaccines was evaluated by assessment of survival rates, body weights, clinical scores, inflammatory factors, and histopathological changes after infecting the immunized mice with Pa PAO1 strains. Besides, the mice were injected with DTC intramuscularly for seven consecutive days to analyze the mechanism of DTC in enhancing immune response using transcriptome sequencing and flow cytometry. Results:All these small compounds were capable of effectively enhancing the immunogenicity of PA0833 formulated with aluminum adjuvant, reducing bacterial loads in lung tissues, inhibiting the secretion of TNF-α, IL-6 and IL-1β, and improving mouse survival rates upon Pa infection. DTC was more effective than the other two compounds. Transcriptome sequencing identified 121 up-regulated genes and 18 down-regulated genes in DTC-treated group as compared with PBS control group. These differentially expressed genes were significantly enriched in immune pathways, with a strong activation of the IL-17 pathway. Flow cytometry analysis demonstrated significant activation of dendritic cells and proliferation of Th17 cells in splenocytes in DTC-treated group as compared with PBS control group. Conclusions:All three small compounds are able of effectively enhance antigen immunogenicity with DTC being the most effective, indicating that DTC can be used as a novel adjuvant in vaccine development.

BACKGROUND:Toll-like receptors are an important class of pattern recognition receptors that have important functions in pathogen immunity and cytokine synthesis by recognizing specific molecular patterns.Previous studies have found that different types of bone tissue cells also express Toll-like receptors.Activation or inhibition of Toll-like receptors can have significant effects on osteoblast and osteoclast function through multiple pathways. OBJECTIVE:To summarize the expression and action pathways of Toll-like receptors in osteoblasts and osteoclasts,in order to further elucidate the biological mechanisms involved in the regulation of Toll-like receptors under physiological and pathological conditions. METHODS:Relevant literature was retrieved from databases such as PubMed and CNKI as of December 2022.The Chinese and English search terms included"Toll-like receptor,osteoblast,osteoclast,mesenchymal stem cells,macrophage,cytokine,signaling pathway".According to the research needs,the corresponding criteria were established to screen the final literature. RESULTS AND CONCLUSION:(1)Toll-like receptors could directly regulate osteoblast and osteoclast differentiation through the activation of related signaling pathways.(2)Toll-like receptor activation induces cytokine production and exerts regulatory effects.(3)Toll-like receptor activation can affect the survival and migration ability of osteoblasts and osteoclasts.(4)Toll-like receptors in osteoblasts and osteoclasts are activated in certain diseases and pathological settings and are involved in intercellular interactions.

BACKGROUND:Tumor necrosis factor-α is a broadly acting inflammatory cytokine that plays an important role in the immune inflammatory response of the body.The current study concluded that tumor necrosis factor-α has significant biological effects on a variety of bone tissue cells. OBJECTIVE:To summarize the expression and action pathways of tumor necrosis factor-α in osteoblastic and osteoclastic cells to further elucidate the regulatory role of tumor necrosis factor-α on bone tissue cells. METHODS:PubMed and CNKI were searched until March 2023,and the Chinese search terms included"tumor necrosis factor α,osteoblast,osteoclast,osteoclast,osteoprogenitor";the English search terms included"TNF-α,osteoblast,osteoclast,osteocyte,osteoprogenitor cell".The corresponding criteria were established according to the research needs,and the final literature was screened.Finally,77 articles were included for review. RESULTS AND CONCLUSION:(1)Tumor necrosis factor-α is participating in regulating the recruitment,appreciation,and differentiation of osteoprogenitor cells,but leads to osteoprogenitor cell stripping and death under specific environments.It also participates in bone resorption directly or indirectly through secreted enzymes.(2)Tumor necrosis factor-α can increase the level of inflammatory factors in the environment by activating relevant signaling pathways in osteoclast lineage cells or directly induce the generation of osteoclasts in specific environments.(3)Tumor necrosis factor-α can inhibit osteogenic differentiation by activating nuclear factor-κB signaling pathway,inhibiting the expression of transcription factors such as RUNX2 and Osterix,and inducing apoptosis and necrotizing apoptosis in osteoblasts.(4)Tumor necrosis factor-α inhibits osteogenesis and promotes osteoclastogenesis by activating the nuclear factor-κB signaling pathway in osteocytes and inducing cytokines such as RANKL,SOST,and DKK1,while enhancing apoptosis of the osteocytes,as well as bone resorption around the apoptotic bone tissue.(5)Taken together,the effect of tumor necrosis factor-α in bone tissue is mainly to inhibit osteogenesis and promote osteoclastosis.The biological effect of tumor necrosis factor-α in bone tissue cells is usually dependent on the activation of tumor necrosis factor receptor and nuclear factor-κB signaling pathways.(6)The interaction of tumor necrosis factor-α with other tissue cell types surrounding bone tissue and its role in bone immune regulation still deserve attention in future studies.

BACKGROUND:Filamin B(FLNB)can crosslink the actin cytoskeleton into a dynamic structure that is essential for the directional movement of cells.It can regulate the proliferation,differentiation and apoptosis of chondrocytes.However,the effect of FLNB on osteoblast proliferation,migration and apoptosis has not been reported. OBJECTIVE:To investigate the effect of FLNB on the proliferation,migration and apoptosis of MC3T3-E1 cells. METHODS:The adenoviral vectors for knockdown of FLNB expression(sh-FLNB1,sh-FLNB2,sh-FLNB3)were constructed and infected with MC3T3-E1 cells.After screened by puromycin drug,the efficiency of FLNB knockdown was detected by western blot and RT-PCR.The MC3T3-E1 cell line with the best efficiency of FLNB knockdown was selected as the stable transient cell line of MC3T3-E1 for subsequent experiments.The cells were divided into blank group,mc3t3 group,sh-NC group(empty vector),and sh-FLNB group(sh-FLNB lentivirus).The blank group was cultured in cell-free α-MEM complete medium;the mc3t3 group was cultured in α-MEM complete medium alone;and the sh-NC and sh-FLNB groups were cultured with α-MEM medium containing 2.5 μg/mL puromycin.After 3 days of culture,cell counting kit-8 assay and cell scratch assay were used to detect the proliferation and migration ability of MC3T3-E1;flow cytometry was used to detect cell apoptosis;and RT-PCR was used to detect the expression of apoptosis-related genes. RESULTS AND CONCLUSION:Western blot and RT-PCR results showed that the efficiency of FLNB knockdown was the best in the sh-FLNB3(P<0.000 1),which was used as a stable cell line for subsequent experiments.Cell counting kit-8 data showed that the proliferative ability of MC3T3 cells was significantly weakened after knockdown of FLNB(P<0.05).Cell scratch assay results showed that the migration ability of MC3T3 cells was significantly decreased after knockdown of FLNB.Flow cytometry and RT-PCR results showed that the apoptotic rate of MC3T3-E1 cells increased after knockdown of FLNB,the expression of pro-apoptotic factor Bax increased significantly,and the expression of anti-apoptotic factor Bcl-2 decreased significantly(P<0.05).To conclude,knockdown of FLNB can reduce the proliferation ability of MC3T3-E1 cells,decrease the migration ability of the cells,and increase cell apoptosis.

Objective:To explore the repair methods and effects of refractory wounds in patients after spinal internal fixation operation .Methods:The study was a retrospective observational study. From November 2020 to October 2023, 10 patients with refractory wounds after spinal internal fixation operation were admitted to the Department of Burns and Plastic Surgery of Changde Hospital of Xiangya School of Medicine of Central South University. They were 3 males and 7 females, aged 35 to 68 years. There were 6 cases of thoracolumbar tuberculosis, 3 cases of thoracolumbar fracture, and 1 case of recurrent sacrococcygeal chordoma with skin, soft tissue, and bone defects after radical resection. The wound areas after debridement were 6.0 cm×1.5 cm to 27.0 cm×6.5 cm. The wound repair operation was decided to perform in the primary stage or in the secondary stage according to the wound situation. Two patients with type Ⅰ wounds were treated with debridement, direct suture, and continuous irrigation and drainage with catheter after operation. Eight patients with type Ⅱ wounds were repaired with local flaps (including rotation flap with dermis-fat flap at the end), muscle flaps, or muscle flaps combined with local flaps. The flap sizes were 10.0 cm×5.0 cm to 27.0 cm×14.0 cm, and the sizes of muscle flap were 8.0 cm×5.0 cm×4.0 cm to 17.0 cm×9.5 cm×2.0 cm. The wounds in flap donor areas were sutured directly. The wound treatment methods of patients with type Ⅱ wounds were recorded. The wound healing was observed after operation. The infection and recurrence of wounds, the retention of internal fixation materials, and spinal motor function were observed during follow-up.Results:Among patients with type Ⅱ wounds, there were 3 cases applied with local flaps (including 1 case with rotation flap with dermis-fat flap at the end), 3 cases with muscle flaps (including 1 case with latissimus dorsi muscle flap and 2 cases with erector spinal muscle flaps), and 2 cases with muscle flaps (1 case with latissimus dorsi muscle flap and 1 case with erector spinal muscle flap) combined with local flaps. Only 1 case with secondary defects after radical surgery of sacrococcygeal chordoma had poor wound healing which healed after dressing change, and the wounds of the remaining 9 cases all healed well. During the follow-up of 4 to 18 months, no infection or recurrence of local wounds developed in 10 patients, the internal fixation materials were not loosening, and there was no significant limitation in spinal motor function.Conclusions:For refractory wounds after spinal internal fixation operation, according to the wound type of patients, debridement, suture, irrigation, and drainage in the primary stage, or transplantation of local flaps, muscle flaps, muscle flaps combined with local flaps are performed in the primary stage or in the secondary stage. These methods are proved to have reliable therapeutic effects, not only repairing the wounds, but also retaining the internal fixation materials.

The cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes signaling pathway plays a central role in cells'ability to sense the presence of abnormal double-stranded DNA within the cytoplasm.Modulation of the function of the cytoplasmic DNA recognition receptor cGAS allows regulation of this signaling pathway.In recent years,research has identified protein post-translational modifications(PTMs),including phosphorylation,acetylation,ubiquitination,methylation,and SUMOylation,as having significant roles in regulating innate immune signaling pathways.This paper reviews how PTMs influence the function of cGAS and its downstream signaling pathways through various mechanisms.

Inflammatory bowel disease(IBD)is a serious disorder,and exploration of active compounds to treat it is necessary.An acidic polysaccharide named SUSP-4 was purified from Selaginella uncinata(Desv.)Spring,which contained galacturonic acid,galactose,xylose,arabinose,and rhamnose with the main chain structure of →4)-α-D-GalAp-(1 → and →6)-β-D-Galp-(1 → and the branched structure of →5)-α-L-Araf-(1 →.Animal experiments showed that compared with Model group,SUSP-4 significantly improved body weight status,disease activity index(DAI),colonic shortening,and histopathological damage,and elevated occludin and zonula occludens protein 1(ZO-1)expression in mice induced by dextran sulfate sodium salt(DSS).16S ribosomal RNA(rRNA)sequencing indicated that SUSP-4 markedly downregulated the level of Akkermansia and Alistipes.Metabolomics results confirmed that SUSP-4 obviously elevated thiamine levels compared with Model mice by adjusting thiamine metabolism,which was further confirmed by a targeted metabolism study.Fecal transplantation experiments showed that SUSP-4 exerted an anti-IBD effect by altering the intestinal flora in mice.A mechanistic study showed that SUSP-4 markedly inhibited macrophage activation by decreasing the levels of phospho-nuclear factor kappa-B(p-NF-κB)and cyclooxygenase-2(COX-2)and elevating NF-E2-related factor 2(Nrf2)levels compared with Model group.In conclusion,SUSP-4 affected thiamine metabolism by regulating Akker-mania and inhibited macrophage activation to adjust NF-κB/Nrf2/COX-2-mediated inflammation and oxidative stress against IBD.This is the first time that plant polysaccharides have been shown to affect thiamine metabolism against IBD,showing great potential for in-depth research and development applications.

The stimulator of interferon genes(STING),an integral adaptor protein in the DNA-sensing pathway,plays a pivotal role in the innate immune response against infections.Additionally,it presents a valuable therapeutic target for infectious diseases and cancer.We observed that fangchinoline(Fan),a bis-benzylisoquinoline alkaloid(BBA),effectively impedes the replication of vesicular stomatitis virus(VSV),encephalomyocarditis virus(EMCV),influenza A virus(H1 N1),and herpes simplex virus-1(HSV-1)in vitro.Fan treatment significantly reduced the viral load,attenuated tissue inflammation,and improved survival in a viral sepsis mouse model.Mechanistically,Fan activates the antiviral response in a STING-dependent manner,leading to increased expression of interferon(1FN)and interferon-stimulated genes(ISGs)for potent antiviral effects in vivo and in vitro.Notably,Fan interacts with STING,preventing its degradation and thereby extending the activation of IFN-based antiviral responses.Collectively,our findings highlight the potential of Fan,which elicits antiviral immunity by suppressing STING degra-dation,as a promising candidate for antiviral therapy.