BACKGROUND:Chitosan has a place in the biomedical field due to its good biological properties and unique physicochemical properties,especially in tissue engineering and drug delivery with good application prospects.OBJECTIVE:To summarize the research progress of the role of chitosan in the repair and regeneration of oral soft and hard tissues.METHODS:A computerized search of CNKI and PubMed databases was performed with the search terms"chitosan,oral mucosal diseases,periodontal diseases,tissue regeneration,bacteriostatic,drug carrier,wound healing"in Chinese and English.The search time limit was from 2010 to 2024.After screening according to the inclusion and exclusion criteria,88 articles were finally included for summary analysis.RESULTS AND CONCLUSION:Chitosan is a promising biomaterial in bone and pulp regeneration as it has the ability to stimulate the recruitment and adhesion of osteogenic progenitor cells and dental pulp stem cells.Chitosan prevents caries,periodontal disease,and candidiasis by inhibiting Streptococcus pyogenes,Porphyromonas gingivalis,and Candida in the oral cavity.Chitosan nanocomposites have higher stability,better biocompatibility,and slow-release properties of drugs and can be enhanced by combining with other chemical reagents to enhance their anticancer properties.Chitosan possesses drug delivery,antibacterial activity,hemostasis and wound healing,which in turn can block the erosion of wounds by saliva and oral flora,relieve pain,repair and promote wound healing.Chitosan promotes the deposition of calcified material,which is conducive to the remineralisation of enamel and dentin.

Objective: To characterize perioperative dynamic changes in immune-cell phenotypes and inflammatory cytokines in patients undergoing CPB (cardiopulmonary bypass) cardiac surgery, and to explore their associations with postoperative outcomes. Methods: In this prospective cohort study, 120 adult patients who underwent elective cardiac surgery under CPB at West China Hospital from May 2022 to March 2023 were enrolled. Perioperative immune-cell phenotypes and concentrations of 40 inflammation-related cytokines were measured. The primary outcomes were the sequential organ failure assessment (SOFA) score at 24 h after surgery and ΔSOFA (the peak SOFA score within 48 h after surgery minus the preoperative SOFA score). Secondary outcomes included major adverse cardiovascular events (MACE), acute kidney injury (AKI), respiratory failure, severe liver injury, and infection. Results: The mean age of enrolled patients was 57±10 years. Of these, 52% (62/120) were male and 90% (108/120) underwent valve surgery. During the rewarming to the end of CPB, neutrophil counts rapidly increased (7.39×10 /L vs preoperative 3.07×10 /L, P<0.001), with significant upregulation of CD11b (7.30×10 /L vs preoperative 3.05×10 /L, P<0.001) and CD54 (7.15×10 /L vs preoperative 2.99×10 /L, P<0.001). Lymphocyte counts increased at the end of CPB (1.75×10 /L vs preoperative 1.12×10 /L, P<0.001) but decreased significantly at 24 h after surgery (0.59×10 /L vs preoperative 1.12×10 /L, P<0.001). Plasma analysis showed that multiple pro-inflammatory cytokines increased during CPB and remained elevated up to 24 h after surgery; five chemokines and the anti-inflammatory cytokine IL-10 peaked at the end of CPB. The SOFA score increased from 1 (1, 2) preoperatively to 7 (5, 10) at 24 h after surgery, with a ΔSOFA of 6 (4, 8). Within 30 days after surgery, 48 patients (40.0%) developed AKI, 17 (14.2%) developed infection, 4 (3.3%) developed severe liver injury, 3 (2.5%) developed respiratory failure, and 3 (2.5%) experienced MACE. During the 2-year follow-up, 8 patients (6.7%) experienced MACE and 5 (4.2%) died. Conclusion: Multi-organ dysfunction is common after cardiac surgery under CPB (median ΔSOFA, 6), accompanied by perioperative activation of multiple immune-cell subsets and upregulation of pro-inflammatory, anti-inflammatory, and chemotactic mediators. This study provides data-driven evidence and research clues for further investigation of the associations between CPB-related immune perturbations and postoperative organ dysfunction and clinical outcomes.

Objective: To analyze the epidemiological characteristics of category C intestinal infectious diseases among children and adolescents in Shenzhen from 2012 to 2024 and the association with meteorological factors, so as to provide a scientific basis for the targeted prevention and control of infectious diseases for children and adolescents. Methods: Using data from the "Infectious Disease Reporting Information Management System" of the "China Disease Prevention and Control Information System" covering the period from January 1, 2012 to December 31, 2024, the study analyzed clinical and confirmed cases of hand, foot, and mouth disease, other infectious diarrhea, and acute hemorrhagic conjunctivitis among individuals aged 6-19 years old to describe demographic and temporal characteristics. It used Joinpoint regression to calculate the average annual percent change (AAPC) and annual percent change (APC) to analyze incidence trends, and Spearman s correlation was combined to generalize linear models so as to assess the association between category C intestinal infectious diseases and meteorological factors. Results: From 2012 to 2024, a cumulative total of 61 019 cases of hand, foot, and mouth disease among children and adolescents, 58 498 cases of other infectious diarrhea, and 6 377 cases of acute hemorrhagic conjunctivitis were reported. The AAPC in the incidence rates of these three diseases was 19.19%, 31.03% and 31.48 %, respectively(all P <0.05). Notably, the incidence of hand, foot, and mouth disease increased significantly after 2022 (APC= 133.66 %, P <0.01). The temporal distribution showed that hand,foot,and mouth disease was most prevalent in May,June and July (seasonal index of 2.39,3.64,1.97), other infectious diarrhea was most prevalent in February,March and December (seasonal index of 1.22,1.25,1.47), and acute hemorrhagic conjunctivitis peaked in September and October (seasonal index of 4.22,2.16). Monthly average temperature could increase the risk of hand,foot,and mouth disease( β = 0.18 ,95% CI =0.11-0.25); as monthly average wind speed increased, the incidence of other infectious diarrhea ( β =-0.86, 95% CI = -1.50 to -0.22) and acute hemorrhagic conjunctivitis ( β =-1.32, 95% CI =-2.60 to -0.05) both decreased (all P < 0.05 ). Conclusions Among children and adolescents in Shenzhen, category C intestinal infectious diseases remain prevalent throughout the year；the number of reported hand, foot, and mouth disease cases has shown an upward trend in recent years.Temperature and wind speed significantly affect the number of reported cases of three types with category C intestinal infectious diseases.

ObjectiveTo investigate the effects of atorvastatin （ATV） on the proliferation and differentiation of rat bone marrow mesenchymal stem cells （BMSCs）， periodontal ligament stem cells （PDLSCs）， and dental pulp stem cells （DPSCs） in vitro， and to validate the regulatory effect of ATV on periodontal bone formation and tooth movement using a rat orthodontic tooth movement （OTM） model. MethodsThe effects of ATV on the proliferation and osteogenic/odontogenic differentiation of rat BMSCs， PDLSCs， and DPSCs were assessed in vitro. CCK-8 assay was used to detect the proliferation of the three types of cells. Alkaline phosphatase （ALP） staining and Alizarin Red staining were employed to evaluate osteogenic differentiation capacity. Western blot was used to detect the expression of osteogenesis-related proteins ［collagen type I （COL-I）， Runt-related transcription factor 2 （Runx2）， bone morphogenetic protein-2 （BMP-2）， osteocalcin （OCN）］ and the odontogenesis-related protein dentin sialophosphoprotein （DSPP） in BMSCs， PDLSCs and DPSCs. An OTM rat model was established， with rats randomly assigned to an ATV gavage group and a control group. The ATV gavage group received daily oral administration of ATV at a dose of 20 mg/kg， while the control group received an equal volume of solvent by gavage. Tooth movement distance was measured via Micro-CT on days 7， 14， and 21. Histomorphology of periodontal tissues was observed using Hematoxylin and Eosin （HE） staining and Masson staining. The gene and protein expression levels of osteogenic markers （BMP-2， Runx2， OCN） on the tension side of the first molar were detected by qRT-PCR and immunohistochemistry， respectively. ResultsATV at concentrations of 1×10⁻⁶ mol/L and 1×10⁻⁷ mol/L significantly promoted the proliferation and osteogenic/odontogenic differentiation of BMSCs， PDLSCs， and DPSCs， manifested as enhanced ALP activity， increased mineralized nodule formation， and up-regulated expression of osteogenic/odontogenic proteins COL-I， Runx2， BMP-2， OCN， and DSPP （P<0.001）. In the OTM model， compared with the control group， the ATV gavage group showed a significant reduction in tooth movement distance （P<0.05）， enhanced osteogenic activity in periodontal tissues， and significantly increased gene （P<0.001） and protein （P<0.05） expression of BMP-2， Runx2， and OCN on the tension side of the first molar. ConclusionATV enhances periodontal osteogenesis by promoting osteogenic/dentinogenic differentiation， thus inhibiting tooth movement.

BACKGROUND:Chitosan has a place in the biomedical field due to its good biological properties and unique physicochemical properties,especially in tissue engineering and drug delivery with good application prospects.OBJECTIVE:To summarize the research progress of the role of chitosan in the repair and regeneration of oral soft and hard tissues.METHODS:A computerized search of CNKI and PubMed databases was performed with the search terms"chitosan,oral mucosal diseases,periodontal diseases,tissue regeneration,bacteriostatic,drug carrier,wound healing"in Chinese and English.The search time limit was from 2010 to 2024.After screening according to the inclusion and exclusion criteria,88 articles were finally included for summary analysis.RESULTS AND CONCLUSION:Chitosan is a promising biomaterial in bone and pulp regeneration as it has the ability to stimulate the recruitment and adhesion of osteogenic progenitor cells and dental pulp stem cells.Chitosan prevents caries,periodontal disease,and candidiasis by inhibiting Streptococcus pyogenes,Porphyromonas gingivalis,and Candida in the oral cavity.Chitosan nanocomposites have higher stability,better biocompatibility,and slow-release properties of drugs and can be enhanced by combining with other chemical reagents to enhance their anticancer properties.Chitosan possesses drug delivery,antibacterial activity,hemostasis and wound healing,which in turn can block the erosion of wounds by saliva and oral flora,relieve pain,repair and promote wound healing.Chitosan promotes the deposition of calcified material,which is conducive to the remineralisation of enamel and dentin.

Objective: To analyze the epidemiological characteristics of varicella among nursery children in Shenzhen from 2015 to 2024, and to evaluate the impact of optimizing varicella vaccine (VarV) immunization strategies on varicella incidence. Methods: Varicella incidence data for nursery children in Shenzhen from 2015 to 2024 were obtained from the China Disease Prevention and Control Information System. The study period was divided into three phases:one dose self pay VarV (January 2015 to October 2017), two dose self pay VarV (November 2017 to October 2019), and two dose free VarV (November 2019 to December 2024). Interrupted time series (ITS) analysis was conducted to assess changes in the level and trend of varicella incidence associated with each phase of policy implementation. Results: A total of 27 517 varicella cases was reported among nursery children from 2015 to 2024, with an average annual incidence of 514.01/100 000. During the same period, 136 clustered outbreaks were reported in nursery institutions, involving a cumulative total of 1 091 cases. ITS analysis showed that during the self pay 1 dose stage, the varicella incidence among nursery children showed an upward trend, with an average monthly increase of 2.58/100 000 (95% CI =2.21/ 100 000 -2.95/100 000, P <0.01). After the implementation of the self pay 2 dose strategy, the incidence decreased, with a change in incidence of -26.12/100 000 (95% CI =-37.30/100 000 to -14.94/100 000) and a change in slope of -2.65/100 000 (95% CI = -3.38/100 000 to -1.93/100 000)(all P <0.01). After the implementation of the free 2 dose strategy, the incidence decreased further, with a change in incidence of -40.03/100 000 (95% CI =-50.39/100 000 to -29.66/100 000, P <0.01) and a change in slope of -0.56/100 000 (95% CI =-1.20/100 000-0.08/100 000, P =0.09). Conclusion The gradual optimization of the VarV vaccination strategy in Shenzhen from self pay 1 dose to free 2 dose has significantly reduced the varicella incidence among nursery children, demonstrating good short term control and long term intervention effectiveness.

This study aims to understand the biological characteristics of Streptococcus dysgalacti-ae of yak origin.Bacterial isolation and identification,drug susceptibility test,virulence gene test and pathogenicity test were carried out on milk samples of yaks from Naqu City to evaluate the bi-ological characteristics of the isolated strains.Meanwhile,molecular biological information such as virulence factors and drug resistance genes were analyzed by whole genome sequencing,and viru-lence genes were verified by PCR.The results showed that a strain of Streptococcus dysgalactiae was isolated from the milk of yak,and its colony morphology was pinpoint size,smooth edge and milky white.This strain is sensitive to many antibiotics(penicillin G,cephalosporin,ciprofloxacin,tetracycline,erythromycin,etc.).Virulence gene test results showed that the strain carries six key virulence genes(cyl,eno,scpB,bca,bac and napr),which may be closely related to its pathoge-nicity.In the pathogenicity test,the mice were listless and less active after infection,but no death occurred during the observation period.The pathological changes of spleen,kidney,liver and lung tissue were found,suggesting that the strain had certain pathogenic potential but not high lethali-ty.Whole genome sequencing data showed that the gene length of this strain was 4 079 280 bp,the GC content was 39.41％,3 964 coding genes were predicted,604 of which were annotated as viru-lence factors,and another 28 gene mutations may enhance its pathogenic ability.Through annota-tion of CARD database,two Pat A resistance genes and two lmrp resistance genes were found,re-vealing their potential resistance mechanism.Through whole genome sequencing technology and bioinformatics analysis method,this study revealed the genomic characteristics,drug resistance and pathogenicity mechanism of Streptococcus dysgalactiae of yak origin.The findings provide impor-tant scientific evidence for further exploration of the pathogenicity,drug resistance mechanisms,and molecular evolution of yak-derived Streptococcus agalactiae.

Objective:To evaluate the Caprini risk assessment model (Caprini RAM) for predicting lower extremity deep vein thrombosis (DVT) after a spinal cord injury (SCI).Methods:Five hundred and one SCI patients were divided into low- (0-1 points, n=130), medium- (2 points, n=43), and high-risk (≥3 points, n=328) groups according to their Caprini scores. The data covering all 501 included gender, age, cause of injury, injury site, American Spinal Injury Association classification, smoking history, surgical history, concurrent pulmonary or urinary tract infections, indwelling catheterization, comorbid type 2 diabetes or hypertension, D-dimer level, fibrinogen level, prothrombin time (PT), activated partial thromboplastin time, international normalized ratio), red blood cell (RBC) count, white blood cell count, platelet (PLT) count and neutrophil percentage. DVTs were detected using lower extremity ultrasound. The Caprini scores were treated as both categorical and continuous variables alongside the other risk factors in multivariate logistic regressions predicting DVT incidence. Generalized additive models were used for curve fitting and threshold saturation analysis, and log-likelihood ratio tests were applied to evaluate the linear relationships observed between Caprini scores and DVT incidence. Results:When the Caprini score was used as a categorical variable, a high risk score ( OR=7.264), age ( OR=1.050), D-dimer ( OR=1.11) , PT ( OR=1.494), PLT count ( OR=1.004) and lung infection ( OR=1.83) were found to be significant independent predictors of DVT. RBC was a protective factor ( OR=0.509). When the Caprini score was used as a continuous variable, lung infection lost its predictive utility. After adjusting for the risk and protective factors, the Caprini scores and the incidence of DVT showed a significant curvilinear increasing association, with a breakpoint of 3. When the Caprini score was less than 3, the incidence of DVT increased 1.83 times with a 1 point increase in the Caprini score. Beyond 3 the multiplier was 1.06. Conclusions:With the independent risk factors accounted for, Caprini scores demonstrate a curvilinear increasing relationship with DVT risk. Clinically, special attention should be given to SCI patients with Caprini scores ≥3.

Objective To investigate the effects of safflower polysaccharide on tumor growth and the Phos-phoinositide 3-kinase(PI3K)/Protein Kinase B(Akt)/Mammalian Target of Rapamycin(mTOR)signaling pathway in colorectal cancer mice.Methods The mouse model of colorectal cancer was established by inoculating SW480 colorectal cancer cells.The successfully modeled mice were divided into five groups:the control group,the low-dose safflower polysaccharide group 15 mg/(kg·day),the medium-dose safflower polysaccharide group 45 mg/(kg·day),and the high-dose safflower polysaccharide group 135 mg/(kg·day).After treatment,tumor volume,mass,and tumor inhibition rate were measured.Immunohistochemistry was used to detect the expression of Proliferating Cell Nuclear Antigen(PCNA)protein.Apoptosis was assessed using the Terminal deoxynucleotidyl Transferase-Mediated Nick End Labeling(TUNEL)method.Hematoxylin-Eosin(HE)staining was performed to observe the morphology of tumor tissues.Real-time polymerase chain reaction(RT-PCR)was employed to measure the expression levels of PI3K,Akt,and mTOR in tumor tissues from each group.Western blot analysis was conducted to evaluate the expres-sion levels of c-Myc,Bcl-2-associated X protein(Bax),and proteins related to the PI3K/Akt/mTOR pathway.Results Compared with the model group,the safflower polysaccharide(low,medium,and high)dose groups exhibited significantly decreased tumor mass and volume,as well as reduced mRNA levels of PI3K,Akt,and mTOR.Additionally,the expression ratios of p-PI3K/PI3K,p-Akt/Akt,p-mTOR/mTOR,and c-Myc protein were notably decreased,while the expression of Bax protein was significantly increased(P<0.05).As the concentration of safflower polysaccharide increased,the tumor inhibition rate also increased(P<0.05).In the model group,tumor tissue from mice showed a higher number of PCNA-positive cells;TUNEL staining revealed minimal green fluores-cence,indicating low apoptosis rates.The tumor cells were closely packed,large in size,and poorly differentiated.Conversely,in the different dosage safflower polysaccharide groups,the expression of PCNA in tumor tissues was markedly reduced,and TUNEL staining positive cells(green)were significantly increased,leading to higher apopto-sis rates(P<0.05).The tumor tissue cells were loosely arranged,with shrunken nuclei and numerous necrotic cells.Conclusion Safflower polysaccharide potentially inhibits the growth of colorectal cancer in mice through suppression of the PI3K/Akt/mTOR signaling pathway.

Objective:To evaluate the Caprini risk assessment model (Caprini RAM) for predicting lower extremity deep vein thrombosis (DVT) after a spinal cord injury (SCI).Methods:Five hundred and one SCI patients were divided into low- (0-1 points, n=130), medium- (2 points, n=43), and high-risk (≥3 points, n=328) groups according to their Caprini scores. The data covering all 501 included gender, age, cause of injury, injury site, American Spinal Injury Association classification, smoking history, surgical history, concurrent pulmonary or urinary tract infections, indwelling catheterization, comorbid type 2 diabetes or hypertension, D-dimer level, fibrinogen level, prothrombin time (PT), activated partial thromboplastin time, international normalized ratio), red blood cell (RBC) count, white blood cell count, platelet (PLT) count and neutrophil percentage. DVTs were detected using lower extremity ultrasound. The Caprini scores were treated as both categorical and continuous variables alongside the other risk factors in multivariate logistic regressions predicting DVT incidence. Generalized additive models were used for curve fitting and threshold saturation analysis, and log-likelihood ratio tests were applied to evaluate the linear relationships observed between Caprini scores and DVT incidence. Results:When the Caprini score was used as a categorical variable, a high risk score ( OR=7.264), age ( OR=1.050), D-dimer ( OR=1.11) , PT ( OR=1.494), PLT count ( OR=1.004) and lung infection ( OR=1.83) were found to be significant independent predictors of DVT. RBC was a protective factor ( OR=0.509). When the Caprini score was used as a continuous variable, lung infection lost its predictive utility. After adjusting for the risk and protective factors, the Caprini scores and the incidence of DVT showed a significant curvilinear increasing association, with a breakpoint of 3. When the Caprini score was less than 3, the incidence of DVT increased 1.83 times with a 1 point increase in the Caprini score. Beyond 3 the multiplier was 1.06. Conclusions:With the independent risk factors accounted for, Caprini scores demonstrate a curvilinear increasing relationship with DVT risk. Clinically, special attention should be given to SCI patients with Caprini scores ≥3.