The small ubiquitin-like modified protein (SUMO) is a protein structurally similar to ubiquitin which is involved in post-translational modification of proteins. SUMOylation refers to the process that SUMO molecule covalently binding to the specific lysine site of target proteins through maturation, activation, binding and ligation by ubiquitin-like specific protease 1 (Ulp1), E1 activating enzyme, E2 binding enzyme, and E3 ligase. SUMOylation alters the activity of target proteins, which is involved in the regulation of various cellular functions such as transcriptional regulation, regulation of embryonic development, cellular stress, maintenance of chromatin structure and genomic stability. In recent years, it has been found that SUMOylation modification is also widely involved in DNA damage repair, especially DNA double-strand breaks (DSBs), which are the most serious types of DNA damage. SUMOylation is involved in almost all processes of DSBs repair, so its role in DNA damage repair has become a research hotspot. In this paper, the research progress of the regulation of SUMOylation in DSBs repair was reviewed.

Objective: To investigate the clinical value of gallbladder-preserving cholelithotomy by natural orifice transumbilical endoscopic surgery on patients with cholecystolithiasis. Methods: A retrospective study was performed on data of 15 patients with cholecystolithiasis, who underwent gallbladder-preserving cholelithotomy by natural orifice transumbilical endoscopic surgery from April 2018 to July 2018. The operative data, including situation of operation, operative time, intraoperative hemorrhage, and postoperative complications were recorded. Results: The procedure was performed successfully in all patients with a mean operative time of 108±12 min (ranged from 92-129 min). The intraoperative hemorrhage was 10-30 mL. Eight patients suffered from slight right upper abdominal pain, and 7 patients felt slight pain in umbilical a week after surgery. No fever, incision infection, umbilical hemia, peritonitis, and ascites were reported. The clear-liquid diet was recommended for one day after operation, and postoperative activity was allowed since the second day after operation. All patients were discharged on the fourth or fifth day, and all recovered to their normal life at one week after discharge. Follow-up showed that the scar was small and hidden in umbilical without visible incision after one month. Ultrasonic examination results showed that gallbladder contractile function worked perfectly in four patients and no gallbladder stone was found after three months. Conclusion Gallbladder-preserving cholelithotomy by natural orifice transumbilical endoscopic surgery is a safe and effective option for patients with cholecystolithiasis, provides excellent cosmetic outcomes, and can be appropriately carried out under the strict control of surgical indications.

Objective: To explore the correlations relating functional MRI (fMRI) and diffusion tensor imaging (DTI) parameters with pre-operative neurological status and post-operative outcomes for patients with cervical spondylotic myelopathy (CSM). Methods: Eighty-seven CSM patients treated with surgical decompression and 38 healthy counterparts were enrolled as the CSM and control groups respectively. DTI and fMRI of the cervical spine were performed while the subjects performed a finger-tapping task with their right hands before the operation and 6 months later. The control group was evaluated only when they were enrolled. All of the patients were given systematic rehabilitation treatment after the surgery. The Japanese Orthopaedic Association (JOA) scoring system for CSM was used to evaluate neurological status, and a JOA recovery rate <50% was defined as a poor recovery. Results: Compared with the healthy controls, the pre-operative patients showed significantly higher volume of activation (VOA) in the left precentral gyrus (PrCG), but that had decreased significantly 6 months after the surgery. Before the surgery, the patients′ fractional isotropy (FA) was significantly less than that of the controls, but it had increased significantly 6 months after the operation. There was no difference in VOA in the left postcentral gyrus (PoCG) between the CSM patients and the controls before the surgery. The VOA ratio (PrCG/PoCG), VOA-PrCG, VOA-PoCG and FA were significantly correlated with both the JOA scores and recovery rates. Receiver operating characteristic (ROC) curve analyses were performed for the predictive ability with respect to surgical outcomes. The largest area under the ROC curve was observed for the VOA ratio (0.805), followed by FA (0.740), and the VOA-PrCG (0.715). The fMRI and DTI showed better potential for predicting functional outcomes than with standard MRI parameters. Multivariate logistic regression revealed that the VOA ratio and FA were independently associated with poor outcomes. Conclusions fMRI and DTI parameters may be more valuable than conventional MRI results for neurological assessment and prognosis with CSM patients. They can also provide references for making up rehabilitation plans.

Objective: To study on the genomic stability of male workers engaged in e-waste dismantling area in Tianjin. Methods: In 2016, an e-waste dismantling area in Tianjin and an area 50 km away from the e-waste dismantling area (no e-waste or other chemical, industrial and agricultural pollution nearby) were selected as the study area and the reference area. Male residents of the study area and male farmers who planted vegetables, fruits, and crops in the reference area were selected as the exposed and reference group by using the convenient sampling method. The exposed group included 146 workers who engaged in e-waste recycling work more than 1 year. The reference group included 121 farmers who never engaged in e-waste recycling work. Questionnaires were used to collect information of all subjects. The semen and peripheral blood were also collected. Trace elements and polychlorinated biphenyl concentration in blood were detected. DNA damage in peripheral blood and sperm was detected, and gene expression was analyzed. DNA damage was assessed using tail DNA% (TDNA%), tail moment (TM) and olive tail moment (OTM) of comet assay. Results: The ages of the exposed group and the reference group were (33.6±12.1) and (33.9±11.9) years old, respectively. The proportions of subjects with exposure time of ≤3, 4-6, ≥7 years were 43% (63 cases), 26% (53 cases) and 21% (30 cases), respectively. The Pb and polychlorinated biphenyl(PCB) concentrations in the exposed group [(90.4±15.3) μg/ml and (101±30) ng/ml, respectively] were higher than those in the reference group [Pb and PCB concentrations were (60.2±8.9) μg/ml, and (2.5±1.4) ng/ml, respectively (both P values <0.05)]. The TDNA%, TM and OTM of peripheral blood and sperm in the exposed group were 5.9%±0.3% and 2.6%±0.90%, 0.93±0.16 and 0.51±0.20, 0.82±0.09 and 0.56±0.07, respectively, which were all higher than those in the reference group [TDNA%, TM and OTM of peripheral blood and sperm were 1.8%±0.2% and 1.9%±0.2%, 0.21±0.04 and 0.32±0.10, 0.19±0.03 and 0.20±0.08, respectively (all P values <0.001)]. The results of gene expression showed that 20 differentially expressed genes, including 13 up-regulated genes and 7 down-regulated genes, were detected in the exposed group compared with the reference group. Conclusion There are obvious DNA damage and DNA repair gene disorder in male workers of an e-waste dismantling area in Tianjin. The current operation mode brings potential health risks to workers.

Objective: To study on the exposure of polychlorinated biphenyl (PCB) contamination and DNA methylation in male employees in an e-waste dismantling area in Tianjin. Methods: In 2016, an e-waste dismantling area in Tianjin and an area 50 km away from the e-waste dismantling area (no e-waste or other chemical, industrial and agricultural pollution nearby) were selected as the study area and the reference area. Male residents of the study area and male farmers who planted vegetables, fruits, and crops in the reference area were selected as the exposed and reference group by using the convenient sampling method. A total of 60 subjects (30 in each of the exposed group and the reference group) were included. The peripheral blood (5 ml) of the study subject was collected, and the PCB concentration was detected. Eight independent subjects in the exposed group and the reference group were randomly selected by random number table method to detect the methylation level of the promoter region of all gene loci, and the mRNA transcript levels. Results: The PCB concentration in peripheral blood of the exposed group was higher than that of the reference group, and the difference was statistically significant (allP values <0.001). The methylation levels of the promoter region of the exposed group and the reference group showed obvious clustering, and 994 gene loci had different degrees of methylation. Compared with the reference group, there were 391 hypomethylation sites and 553 hypermethylation sites in the exposed group. The proportion of methylation sites in the high CpG-rich region was 59.2% and 48.1%, respectively. The mRNA level of the hypomethylated gene in the exposed group was higher (FAM131A, HBM), and the transcription level of the hypermethylated gene was lower (CAPN15, NFIC, SHISA5, FGF13, GRAMD1A, CLEC3B, LILRB2, DCAF7). The mRNA transcription levels of 10 genes above in the exposed group and the reference group were statistically significant (all P values <0.001). Conclusion The PCB concentration of peripheral blood in the exposed population of e-waste is high. PCB exposure changes the methylation level of specific genes and affects the mRNA transcription level of some genes.

Objective To study the effect of human umbilical cord mesenchymal stem cells (hMSCs) on the survival rate of mice with radiation-induced intestinal injury and its effect on the repair of intestinal damage.Methods Adult C57BL/6J mice were selected and divided into control group and abdomen irradiation + PBS(IR + PBS) group and abdominal irradiation+hMSCs transplantation treatment (IR+hMSCs)group.Intestinal injury model was induced by abdominal irradiation at 13 Gy of T ray and the 30-day survival rate was recorded.On the 3.5th and 5.0th day after irradiation,HE staining was used to observe changes in the villus structure and thc number of intestinal crypts in each segment of the small intestine (duodenum,jejunum,and ileum).Results The survival rate of IR+hMSCs group was significantly higher than that of IR+PBS group (P＜0.05).On the 3.5th day after 13 Gy of abdomen irradiation,the duodenum,cavities and ileum villus in IR+PBS group were all fractured,the length was shortened,and the numbers were sparse when compared with the control group,while the hMSCs reduced the intestinal damage.On the 5.0th day after irradiation,the structural integrity of the small intestine in IR+PBS group was repaired slightly,but it still more serious than that of IR+hMSCs group (P＜0.01).The amount of intestine crypts were significantly higher in IR+hMSCs group than that of IR+PBS group,but were significantly lower than that of control group (P＜0.01) at 3.5th day and 5.0th day after radiation.Conclusion Transplantation of hMSCs can improve the survival rate and promote the repairation of intestinal injury induced by radiation in mice.MSCs are hopeful to be used on the treatment of radiation-induced intestinal injury.

Objective To investigate the role and possible mechanisms of paracrine in radiation tolerance of non-small cell lung cancer (NSCLC) by observing the effects of radiation-resistant NSCLC H460R cell secretion on the radiosensitivity of parental H460 cells. Methods H460 cells were inoculated and cultured, and then divided into control group, conditional culturing group, irradiation group and irradiation combined conditional culturing group. One-time irradiation with 137Cs γ-rays was conducted with a dose rate of 1.02 Gy/min. Effect of H460R conditioned media on the radiation sensitivity of H460 cells was observed by clonogenic assay. The percentage of phospho-histone histone H2AX (γH2AX) positive cells was detected by immunofluorescence staining. The cyclical changes of the cells were detected by flow cytometry. The expression of DNA damage-associated proteinsγH2AX and Rad51 were detected by Western Blot. Results The results showed that compared with the singleγ-rays irradiation, the number of cell clones was significantly increased in the H460R cells after γ-rays irradiation combined with conditional culturing treatment at different doses of 2, 4, and 6 Gy, and the differences were statistically significant (2,4 Gy:all P<0.05;6 Gy:P<0.01). The results of immunofluorescence staining showed that the percentage ofγH2AX positive cells in the conditional culturing group was higher than that in the control group [(39.40±2.51)％vs. (25.21± 2.05)％], and the difference was statistically significant (P<0.01). This value in the irradiation combined conditional culturing group was lower than that in irradiated group [(60.48±2.79)％vs. (80.65±2.05)％], and the difference was statistically significant (P<0.001). The flow cytometry analysis showed that the percentage of cells in G2/M phase for the irradiation (4 Gy) combined conditional culturing group was higher than that of irradiated group [(26.83± 1.42)％ vs. (15.73±1.29)％], and the difference was statistically significant (P<0.001). The Western Blot results showed that γH2AX and Rad51 protein expression in the irradiation (4 Gy) combined conditional culturing group respectively was lower and higher than that in irradiated group. Conclusion In the tumor microenvironment, radiation-resistant H460R cells can enhance the radioresistance of H460 cells by paracrine, which may be related to the promotion of DNA repair ability after irradiation

In order to effectively improve the radiation sensitivity of tumors and reduce the side effects during radiotherapy,people have been working on the development of radiation sensitizers.In recent years,many researches focused on the nanoparticles with high atomic number elements as radiosensitizers.Researchers have recently developed a kind of new gadolinium-based radiation-sensitizing nanoparticles,i.e.AGUIX,which have low toxicity,low quality,and radiation-activated drug activity.These nanoparticles are consisted by a polysiloxane core and a network of covalently attached gadolinium chelates.They have a hydrodynamic diameter of less than 5 nm,and can be administered intravenously due to the preferential accumulation in tumor sites and elimination by kidney.Studies have proved that AGUIX can be used as a safe and effective radiation sensitizer under various irradiation conditions.In addition,due to the presence of strontium,AGUIX itself can also be used as a MRI contrast agent to monitor the biodistribution of drugs and tumor evolution,and then guide the development of radiotherapy.In this paper,the research progress of AGUIX in recent years was reviewed.

Objective To clarify the relationship between intracranial pressure monitoring and prognosis of patients with traumatic brain injury after decompressive craniectomy.Methods From December 2015 to December 2017,48 head-injured patients in Affiliated Suzhou Hospital of Nanjing Medical University were enrolled,who were underwent decompressive craniectomy in this retrospective study.The patients were subdivided into 2 groups based on whether postoperative was monitored (n =19) or not (n =29).The prognosis was evaluated by Glasgow Outcome Scale score,with 1 point of prognosis death,2 to 3 points of poor prognosis,and 4 to 5 points of good prognosis.Count data were expressed as a percentage (％).Count data were expressed as percentage (％).The chi-square test was used to compare the difference in the rate of good prognosis and mortality between the two groups.Results The mortality of monitoring group (10.5％) was significantly lower than that of control group (37.9％) (x2 =4.365 5,P =0.036 7) during hospitalization,The rate of good prognosis in the monitoring group (68.4％) and the control group (44.8％) was not statistically significant (x2 =2.573 8,P =0.108 6).Condusion The study showed that continuous monitoring in patients with severe craniocerebral injury could reduce the mortality of patients during hospitalization,but had no significant effect on the improvement of prognosis.

Objective To investigate the traits of anxiety characteristics and its influencing factors in children with tic disorders ( TD) . Methods 31 children with tic disorders and 32 normal children were assessed by the screen for child anxiety related emotional disorders(SCARED), eysenck personality ques-tionnaire(EPQ) for child,attachment security scale and egma minnen av bardndosnauppforstran(EMBU).In-dependent sample t-test was used to compare the differences in anxiety disorders between the children of the two groups,and Pearson correlation and multivariate linear step-by-step regression analysis were used to ana-lyze the effects of personality traits,parent-child attachment and parental education on anxiety. Results So-matization/panic and separation anxiety in TD((6.20±5.33),(4.87±3.18)) were higher than those in con-trol group((3.75±3.34),(3.06±2.61);both P<0.05).There was positive correlation between somatization/panic and children's personality of introversion-extroversion(E),psychoticism(P),excessive interference mother,the mother refusal and denial,mother severely punishment(r=0.580,0.427,0.399,0.674,0.575,P<0.05 or P<0.01),and negative correlation between somatization/panic and mother closeness(r=-0.365,P<0.05).Generalized anxiety was positively correlated with E,P,lie,excessive interference mother,the mother refusal and denial,mother severely punishment(r=0.604,0.543,0.526,0.365,0.613,0.395,P<0.05 or P<0.01) . Separation anxiety was positively correlated with E, lie, the mother refusal and denial ( r=0. 440, 0.401,0.365,P<0.05).Social phobia was positively correlated with excessive interference mother,the mother refusal and denial (r=0.367,0.482,P<0.05 or P<0.01).School phobia was not only positively associated with E, N, P, excessive interference mother, the mother refusal and denial, mother severely punished ( r=0.635,0.449,0.526,0.463,0.541,0.589,P<0.05 or P<0.01),but also negatively correlated with mother closeness(r=-0.394,P<0.05).The mother refusal and denial affected on somatization/panic and social pho-bia(accounted for 45.4％,23.2％) ,the mother refusal and denial and lie affected on generalized anxiety( ac-counted for 51.0％) ,E affected on separation anxiety( accounted for 19.3％) ,E and mother severely punish-ment affected on school phobia( accounted for 50.0％) ,the mother refusal and denial and E affected on total anxiety( accounted for 49.4％) . Conclusions Somatization/panic and separation anxiety in children with tic disorder is higher than that in normal children.Anxiety disorder is mainly affected by fewer mother's encour-agement and tolerance,and children's extroversion.