1.Antibacterial efficacy of HMME-PDT on Enterococcus faecalis within infected simulated lateral canals in vitro model with different energy
Zhaohui ZOU ; Panpan SUN ; Yadong TAO ; Huijuan YIN ; Yingxin LI
International Journal of Biomedical Engineering 2013;(1):22-25
Objective The purpose of this study was to assess the antibacterial effects of hematoporphyrin monomethylether-photodynamic therapy (HMME-PDT) on Enterococcus faecalis within infected simulated lateral canals in vitro with different energy.Methods Simulated lateral canals were prepared on extracted teeth.The specimens were infected with Enterococcus faecalis and then were randomly divided into eight groups.Group A was considered as negative control,its specimens were irrigated with physiological saline.Group B was the positive control,they were irrigated with 5.25% NaClO.Other groups were incubated with HMME at concentration of 40 μg/ml for 5 min,followed by exposure to light at 532 nm for 120 s with different powers in a spiral pattern.Groups were named C-H,in corresponding with the power 50,60,70,80,90,100 mW.Microbial samples (the dentin chips from simulated lateral canals) were taken before and after the treatments.The survival fractions in each simulated lateral canal was calculated by counting colony-forming units(CFUs).Results 1.The HMME-PDT-treated groups resulted in a significant reduction in the number of E.faecalis in simulated lateral canals compared with the negative controls(P<0.05).2.The antibacterial effects of group D、E、F、G、H were higher than the NaCl0-irrigated group(P<0.05).3.The difference of antibacterial effects between the F、G、H groups was in significant(P>0.05).Conclusion HMME-PDT had significant inhibitive efficacy on Enterococcus faecalis within infected simulated lateral canals and the efficacy was power-depended.It can play the best effect with the power of 80 mW.
2.Photodynamic therapy of oral pathogenic bacteria and its potential application
Zhaohui ZOU ; Yingxin LI ; Yanan ZHANG ; Xiaolan JIN
International Journal of Biomedical Engineering 2013;36(4):245-249
Photodynamic therapy (PDT) has been wildly used in the treatment of tumors and dermatologic diseases,especially,when the traditional therapies are ineffective or bring side effects.Moreover,with the deepening of the studies,its effects in anti-microbial has been found.PDT in the treatment of infectious diseases has attracted more and more attention of scholars.In this review,we discussed the mechanism of the PDT,studies in the sterilization of a variety of oral pathogenic bacteria by the PDT and its potential applications in clinic.
3.Effects of photodynamic therapy on the activity and structure of the dental plaque biofilms
Zhaohui ZOU ; Xiuming CHANG ; Huijuan YIN ; Yingxin LI
International Journal of Biomedical Engineering 2012;35(3):169-172,后插4
ObjectiveTo investigate the effects of photodynamic therapy(PDT) on the activity and structure of the dental plaque biofilm formed by the main cariogenic bacteria.MethodsS.mutans,S.sangius,L.acidophilus and A.viscosus were chosen as the experimental bacteria to establish dental plaque biofilm model.They were separated into three groups:group of PDT、group of chlorhexidine and group of normal saline.The influence of the dental plaque biofilms was observed according to plate counting of bacteria method.The changes in the structure of biofilms after PDT were analyzed by means of confocal laser scanning microscopy.Results Compared to normal saline group,chlorhexidine cariogenic bacteria (CFU/ml) in plaque biofilms significantly reduced (P<0.05),with the bactericidal rate 57.84%.After PDT treatment against artificial caries model,the number of cariogenic bacteria (CFU/ml) in plaque biofilms reduced more significantly (P<0.05),the bactericidal rate up to 94.92%,and the structure of dental plaque biofilns changed evidently.ConclusionPDT is an effective method in eliminate cariogenic bacteria of dental plaque biofilms and to destroy the integrity of dental plaque biofilms,and it is a promising method for elimination of dental plaque and prevention of caries.
4.Riboflavin inhibited ischemia brain damage in rats
Minghua RUAN ; Yingxin ZOU ; Jie LUAN ; Zhiyong CHU
Chinese Pharmacological Bulletin 2016;32(8):1115-1120,1121
Aim To investigate the protective effect of riboflavin on ischemia brain damage and the mecha-nism.Methods The in vivo experiments were pro-cessed in male SD rats .Rats were randomly arranged into control group , model group and riboflavin group . The rats in riboflavin group were intraperitoneally in-jected riboflavin at the dose of 1 mg? kg -1 for seven consecutive days .Then the rats in model and riboflavin groups were carried out middle cerebral artery occlu-sion( MCAO) operation.After 24 h, all rats were sacri-ficed and the brain tissue was dissected to observe the infarct area, the edema and the ultrastructure damage . The brain tissue was dyed by triphenyl tetrazolium chloride .The brain edema was observed by the weight of ischemia-side semi-brain.The ultrastructure was ob-served by electron microscope .The in vitro experiments were processed in primary culture neurons by exposed to oxygen and glycose deprivation ( OGD) .The viability of neurons was assayed by MTT method .The enzyme activity of superoxide dismutase ( SOD) , catalase ( CAT)and glutathione peroxidase ( GSH-Px ) was assayed to explore the mechanism .Results Riboflavin signifi-cantly decreased the infarct area ( P<0.01 ) , inhibited the brain edema ( P <0.01 ) and inhibited the ultra-structure damage in rats after MCAO;riboflavin protec-ted the viability ( P <0.01 ) and the ultrastructure of neurons exposed to OGD .The enzyme activity of an-tioxidant SOD1 ( P <0.01 ) , CAT ( P <0.01 ) and GSH-Px ( P <0.01 ) was protected by riboflavin in MCAO model .No difference was found in the activity of SOD2 . Conclusion Riboflavin inhibits ischemia brain damage , and the protection of the activity of an-tioxidants is involved in the mechanism .
5.Study of the effective of efflux pump inhibitors in photodynamic therapy inhibition the cariogenic bacteria in dental plaque biofilms
Zhaohui ZOU ; Yadong TAO ; Panpan SUN ; Huijuan YIN ; Yingxin LI
International Journal of Biomedical Engineering 2013;36(3):156-159,封3
Objective To Study the effect of efflux pump-inhibitors(EPI)-Verapamil in photodynamic therapy (PDT) using hematoporphyrin monomethylether (HMME) as photosensitizer on the cariogenic bacteria in dental plaque biofilms.Methods According to the administrator order of the verapamil and photosensitizer in PDT,streptococcus mutans,streptococcus sanguis,eosinophilic lactobacillus and actinomyces viscosus were used to establish the dental plaque biofilm model.The experiment was divided into five groups,group A was incubated with the photosensitizer and verapamil group,group B using verapamil before incubated the photosensitize,group C suing photosensitizer before incubated verapamil,group D with PDT only,group E was control group.After laser treatment,the influence of the dental plaque biofilms was observed by confocal laser scanning microscope.Results As saline-treated group is a group of normal the dental plaque biofilms.In PDT only group,compared with the saline group,red fluorescence increased significantly,the bacteria lose accumulation capacity,and were isolated and scattered in dispersed state.In PDT plus verapamil group,compared with only PDT group,green staining increased,bacterial activity increased.In group B,cells were incubated with verapamil before incubated the photosensitizer group,green staining increased significantly,red fluorescence reduced,indicating live bacteria increased,and bacteria activity was significantly increased.Conclusion PDT is an effective method in eliminating cariogenic bacteria of dental plaque biofilms.Bacterial efflux pump inhibitors can lower HMME-PDT inhibition cariogenic bacteria in dental plaque biofilm,and pre-verapamil administration could significantly inhibit the effect of PDT treatment of dental caries.
6.Predictive value of lymph node ratio for postoperative distant metastasis of stage III colorectal cancer.
Huchen XUE ; Xiaohui DU ; Chunhong XIAO ; Yang YAN ; Zhenyu ZOU ; Yingxin XU
Journal of Southern Medical University 2014;34(4):458-462
OBJECTIVETo investigate the predictive value of metastatic lymph node ratio for postoperative distant metastasis in patients with colorectal cancer.
METHODSThe clinicopathological data were collected from 180 patients with colorectal cancer who underwent surgical resection in General Hospital of PLA between from January, 2007 to January, 2012. The patients were divided into 2 groups according to the presence of distant organ metastasis and the clinicopathological factors were analyzed with Chi-square test and logistic regression.
RESULTSOf the 118 surgical patients enrolled, 118 were free of distant metastasis and 62 had distant metastasis involving the liver (39 cases), lungs (12 cases), and multiple organs (11 cases). The gross types, differentiation, ELN and LNR of the tumors differed significantly between the two groups. Logistic regression analysis showed that LNR was an independent factor correlating to distant metastasis of colorectal cancer.
CONCLUSIONLNR is independently correlated with distant organ metastasis of colorectal cancer and serves as an important predicative factor for estimating the prognosis of colorectal cancer.
Adult ; Aged ; Aged, 80 and over ; Colorectal Neoplasms ; diagnosis ; pathology ; Female ; Humans ; Lymph Nodes ; pathology ; Lymphatic Metastasis ; diagnosis ; Male ; Middle Aged ; Postoperative Period ; Prognosis ; Young Adult
7.Lipopolysaccharide induces aging phenotype of hematopoietic stem cells in bone marrow and spleen of young mice
Ke BAI ; Mi ZOU ; Qiang ZHAN ; Yingxin HUANG ; Zhenyu JU ; Zhiyang CHEN
Chinese Journal of Pathophysiology 2024;40(1):38-46
AIM:This study aim to investigate the effects of lipopolysaccharide(LPS)-induced inflammation on the aging phenotype of hematopoietic stem/progenitor cells(HSPCs)in the bone marrow(BM)and spleen of mice.METHODS:(1)Young(2-month old)wild-type(WT)mice were treated with LPS to establish an actue inflammation model.The percentage of HSPCs in the BM and spleen of mice after LPS stimulation,as well as the ratio of mature cells in peripheral blood(PB)and spleen,were analyzed using flow cytometry.The proliferation of HSPCs in the BM and spleen was evaluated by examining the expression of the proliferation marker Ki67.In addition,changes in CD45 expression on HSPCs in the spleen of mice following LPS exposure were investigated by flow cytometry.(2)The percentage of HSPCs in BM and mature cells in PB and spleen of both young(2-month old)and old(24-month old)WT mice were analyzed by flow cytometry.(3)The transcriptome changes of hematopoietic stem cells(HSCs)after LPS stimulation was performed by an in silico analysis.RESULTS:(1)Mice exposed to LPS exhibited a significant increase in the percentage of HSPCs in BM and a marked elevation in the percentages of myeloid cells in PB and spleen compared to the mice in control group(P<0.05).(2)LPS exposure resulted in increased spleen weight and cell counts(P<0.05),along with a higher per-centage of HSPCs in the spleen compared to controls(P<0.05).(3)LPS stimulation promoted the proliferation of HSPCs in the BM and spleen(P<0.05).(4)The expression of CD45 was reduced on HSPCs from spleen of mice after LPS stimu-lation(P<0.01).(5)In comparison to young mice,aged mice showed an increase in spleen weight and a higher percent-age of HSPCs in the spleen(P<0.05).(6)Aged mice,in comparison to young mice,demonstrated a significantly higher percentage of HSPCs in the BM and myeloid skewing in the PB and spleen(P<0.01).(7)The silico analysis revealed up-regualtion of reactive oxygen species(ROS)and apoptosis signaling in HSPCs following LPS stimulation.CONCLU-SION:Young HSPCs stimulated by LPS exhibited an increase in cell number,a bias towards myeloid differentiation,en-hanced extramedullary hematopoiesis,and elevated levels of ROS and apoptosis,all of which collectively manifested the aging phenotype of HSPCs.