Objective To investigate the role of bacterial flagellin and CD98 in ulcerative colitis (UC).Methods A total of 60 first episode patients with active UC were recruited,including 30 mild and 30 moderate to severe UC cases.The serum of 30 healthy volunteers and normal intestinal tissues surgically removed from 15 colon cancer patients (more than 5 cm away from surgical margins) were collected as control.The content of bacterial flagellin antibodies in peripheral blood were measured with enzyme-linked immunosorbent assay (ELISA).The expression of CD98 in peripheral blood T lymphocyte was measured by flow cytometry (FACS).The expression of bacterial flagellin protein in intestinal mucosa and CD98 in intestinal epithelial basement membrane was tested by immunohistochemistry (IHC).The comparison between two groups was performed with the SNK-q method,the R×C table x2 test was used to analyze the counted data,and the Spearman correlation was used to analyze the rank materials.Results The peripheral blood concentration of bacteria flagella protein antibody of control group,mild UC group and moderate to severe group showed an upward trend,which was (7.603±2.118) pg/ml,(13.702±3.131) pg/ml and (20.813±3.004) pg/ml respectively,and the differences among groups were statistically significant (F=13.57,P＜0.01).The expression percentage of bacteria flagella protein in intestinal mucosa of the three groups also showed an upward trend,which was 3/15,56.67％ and 73.33％ respectively,and the differences among groups were statistically significant (x2 =11.553,P=0.003).The positive rate of CD98 expression in peripheral blood T lymphocytes of the three groups showed an upward trend,which was (28.42±4.31)％,(32.45±6.71)％ and (43.40±5.09) ％ respectively,and the differences among groups were statistically significant (x2 =10.110,P=0.007).The positive rate of CD98 expression in intestinal epithelial cells of the three groups also showed an upward trend,which was 1/15,36.67 ％ and 66.67％ respectively,and the differences among groups were statistically significant (x2 =5.400,P＜0.05).There was positive correlation between the peripheral blood concentration of bacteria flagella protein antibody and the expression of CD98 in peripheral blood T lymphocytes (r=0.548,P＜0.05).Conclusion Bacterial flagellin and CD98 may be important factors causing inflammatory reaction activity in UC.

Objective To evaluate the influence of narrow-band ultraviolet B on lesional microvessel density (MVD),vascular endothelial growth factor (VEGF),matrix metalloproteinases 2 (MMP-2)as well as on serum VEGF in patients with psoriasis vulgaris(PV).Methods Fifteen patients with PV were recruited into this study with 10 normal human controls.All patients received NB-UVB phototherapy thrice a week for 4-5 weeks.Prior and after the treatment,psoriasis area and severity index (PASI)was calculated,tissue specimens were taken from non-photoexposed lesions,and sera samples were obtained from these patients.Then,MvD and the expression level of VEGF and MMP-2 were measured by immunohistochemical labeled dextran polymer(LDP)method in the tissue specimens.Also,the serum level of VEGF was tested by enzyme-linked immunosorbent assay(ELISA).Results PASI score remarkably decreased in patients after the photothempy(t=13.35,P＜0.01).The MVDs were 20.52±5.02,7.33±1.24 and 4.26±0.79 capillaries per high power field(400 × amplification),in psoriatic lesions before treatment,after treatment,and normal control tissues,respectively,with a significant difference among the three groups (F=97.57,P＜0.05),and a significant increase was observed in the lesions before treatment compared with those after treatment and normal controls.The serum level of VEGF was 307.55±121.65 ng/L in psoriatic lesions before treatment,significantly higher than that after treatment(163.92±95.57 ng/L),and in normal control skin (139.78±79.06 ng/L),whereas there was no significant difference between the latter two groups(P＞0.05).The positivity rate of MMP-2 was similar among the three groups without statistical difference(P＞0.05).In psoriatic patients,a positive correlation was observed among PASI score,MVD,lesional and serum VEGF levels(P＜0.05),also among the MVD,VEGF and MMP-2 levels in lesions(P＜0.05).but lesional MMP-2 was unrelated to PASI score or sgrum VEGF(both P＞0.05).Conclusions NB-UVB may regulate superficial dermal microvascular proliferation by acting on the expression of VEGF in sera and lesions of psoriatic patients.VEGF and MMP-2 may bOth participate in the proliferation process of microvessels,while MMP-2 is unlikely to be involved in the therapeutic mechanism of NB-UVB.

Objective To analyze the impact of Helicobacter pylori standard strain (Hp P12) and its virulence factor vacuolating cytotoxin A ( VacA) on DNA damage and homologous recombination ( HR) repair in a human gastric epithelial cell line (GES-1). Methods Strains of Hp P12 and vacA gene knock-out Hp P12 ( Hp P12 ΔvacA) were respectively used to infect GES-1 cells at a multiplicity of infection of 100. GES-1 cells treated with etoposide (50μmol/L) or mitomycin (0. 5μg/ml) for 2 h were used as posi-tive control. Western blot and immunofluorescence were performed to detect the expression of DNA damage marker protein γH2AX and key HR repair proteins (Rad51, pMRE11, CtIP and pCtIP) and the recruitment of them at DNA damage sites. Human embryonic kidney HEK-293 ( DR-GFP) cells were infected with Hp P12 and Hp P12 ΔvacA strains to verify the impact of VacA on HR repair efficiency. Results The expres-sion and recruitment of γH2AX and key HR repair proteins ( Rad51, pMRE11, CtIP and pCtIP) were in-creased in Hp P12-infected cells as compared with that in uninfected and Hp P12 ΔvacA-infected cells ( all P<0. 05). To evaluate the HR repair efficiency, I-SceⅠ plasmid-transfected HEK-293 (DR-GFP) cells were infected with Hp P12 and Hp P12 ΔvacA and the results showed that green fluorescent protein ( GFP)-positive cells were decreased after infection, especially in Hp P12 ΔvacA-infected cells (both P<0. 05). Conclusions Hp P12 infection could cause DNA damage and promote HR repair in GES-1 cells, in which the virulence factor VacA played an important role.

Objective:To investigate the effectiveness and safety of nasojejunal tube placement in children by gastroscopic drafting method.Methods:We retrospectively analyzed the clinical data of children with nasojejunal tube placement from January 2016 to December 2021 in our hospital, and compared the operation time, successful rate and complications of nasojejunal tube placement in the gastroscopic wire drawing method retraction group(observation group)and the gastroscopic foreign body clamp placement method placement group(control group).Results:All of the 167 cases, 65 cases were in observation group and 102 cases in control group.There were no significant differences in sex and age between two groups( P>0.05). The operation time was(6.7±0.8)min in observation group and(8.2±1.3)min in control group, and the difference was statistically significant( t=8.312, P<0.001). The successful rate was 100% in observation group and 96% in control group.One child in control group complicated with the mucosal erosion and bleeding in the duodenal bulb, while the observation group with no erosion, bleeding, perforation, and other complications. Conclusion:The gastroscopic wire drawing method of nasojejunal tube placement has a shorter operation time, higher successful rates, and lower complication rates, which is significantly superior to the gastroscopic foreign body clamp placement method.

Objective:To conduct a comparative analysis of the radiation damage to zebrafish embryos and the associated biological mechanism after ultra-high dose rate (FLASH) and conventional dose rate irradiation.Methods:Zebrafish embryos at 4 h post-fertilization were exposed to conventional and FLASH irradiation (9 MeV electron beam). The mortality and hatchability of zebrafish after radiation exposure were recorded. Larvae at 96 h post-irradiation underwent morphological scoring, testing of reactive oxygen species (ROS) levels, and analysis of changes in oxidative stress indicators.Results:Electron beam irradiation at doses of 2-12 Gy exerted subtle effects on the mortality and hatchability of zebrafish embryos. However, single high-dose irradiation (≥ 6 Gy) could lead to developmental malformation of larvae, with conventional irradiation showing the most significant effects ( t = 0.87-9.75, P < 0.05). In contrast, after FLASH irradiation (≥ 6 Gy), the ROS levels in zebrafish and its oxidative stress indicators including superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) were significantly reduced ( t = 0.42-15.19, P < 0.05). There was no statistically significant difference in ROS levels in incubating solutions after conventional and FLASH irradiation ( P > 0.05). Conclusions:Compared to conventional irradiation, FLASH irradiation can reduce radiation damage to zebrafish embryos, and this is in a dose-dependent manner. The two irradiation modes lead to different oxidative stress levels in zebrafish, which might be a significant factor in the reduction of radiation damage with FLASH irradiation.