[Effects of gelatin methacrylate anhydride hydrogel loaded with small extracellular vesicles derived from human umbilical cord mesenchymal stem cells in the treatment of full-thickness skin defect wounds in mice]

Objective: To investigate the effects of gelatin methacrylate anhydride (GelMA) hydrogel loaded with small extracellular vesicles derived from human umbilical cord mesenchymal stem cells (hUCMSCs-sEVs) in the treatment of full-thickness skin defect wounds in mice. Methods: This study was an experimental study. hUCMSCs-sEVs were extracted by ultracentrifugation, their morphology was observed through transmission electron microscope, and the expression of CD9, CD63, tumor susceptibility gene 101 (TSG101), and calnexin was detected by Western blotting. The human umbilical vein endothelial cells (HUVECs), the 3rd and 4th passages of human epidermal keratinocytes (HEKs) and human dermal fibroblasts (HDFs) were all divided into blank control group (routinely cultured) and hUCMSC-sEV group (cultured with the cell supernatant containing hUCMSCs-sEVs). The cell scratch test was performed and the cell migration rates at 6, 12, and 24 h after scratching were calculated, the cell Transwell assay was performed and the number of migration cells at 12 h after culture was calculated, and the proportion of proliferating cells was detected by 5-acetylidene-2'-deoxyuridine and Hoechst staining at 24 h after culture, with sample numbers being all 3. The simple GelMA hydrogel and the GelMA hydrogel loaded with hUCMSCs-sEVs (hereinafter referred to as hUCMSC-sEV/GelMA hydrogel) were prepared. Then the micromorphology of 2 kinds of hydrogels was observed under scanning electron microscope, the distribution of hUCMSCs-sEVs was observed by laser scanning confocal microscope, and the cumulative release rates of hUCMSCs-sEVs at 0 (immediately), 2, 4, 6, 8, 10, and 12 d after soaking hUCMSC-sEV/GelMA hydrogel in phosphate buffer solution (PBS) were measured and calculated by protein colorimetric quantification (n=3). Twenty-four 6-week-old male C57BL/6J mice were divided into PBS group, hUCMSC-sEV alone group, GelMA hydrogel alone group, and hUCMSC-sEV/GelMA hydrogel group according to the random number table, with 6 mice in each group, and after the full-thickness skin defect wounds on the back of mice in each group were produced, the wounds were performed with PBS injection, hUCMSC-sEV suspenson injection, simple GelMA coverage, and hUCMSC-sEV/GelMA hydrogel coverage, respectively. Wound healing was observed on post injury day (PID) 0 (immediately), 4, 8, and 12, and the wound healing rates on PID 4, 8, and 12 were calculated, and the wound tissue was collected on PID 12 for hematoxylin-eosin staining to observe the structure of new tissue, with sample numbers being both 6. Results: The extracted hUCMSCs-sEVs showed a cup-shaped structure and expressed CD9, CD63, and TSG101, but barely expressed calnexin. At 6, 12, and 24 h after scratching, the migration rates of HEKs (with t values of 25.94, 20.98, and 20.04, respectively), HDFs (with t values of 3.18, 5.68, and 4.28, respectively), and HUVECs (with t values of 4.32, 19.33, and 4.00, respectively) in hUCMSC-sEV group were significantly higher than those in blank control group (P<0.05). At 12 h after culture, the numbers of migrated HEKs, HDFs, and HUVECs in hUCMSC-sEV group were 550±23, 235±9, and 856±35, respectively, which were significantly higher than 188±14, 97±6, and 370±32 in blank control group (with t values of 22.95, 23.13, and 17.84, respectively, P<0.05). At 24 h after culture, the proportions of proliferating cells of HEKs, HDFs, and HUVECs in hUCMSC-sEV group were significantly higher than those in blank control group (with t values of 22.00, 13.82, and 32.32, respectively, P<0.05). The inside of simple GelMA hydrogel showed a loose and porous sponge-like structure, and hUCMSCs-sEVs was not observed in it. The hUCMSC-sEV/GelMA hydrogel had the same sponge-like structure, and hUCMSCs-sEVs were uniformly distributed in clumps. The cumulative release rate curve of hUCMSCs-sEVs from hUCMSC-sEV/GelMA hydrogel tended to plateau at 2 d after soaking, and the cumulative release rate of hUCMSCs-sEVs was (59.2±1.8)% at 12 d after soaking. From PID 0 to 12, the wound areas of mice in the 4 groups gradually decreased. On PID 4, 8, and 12, the wound healing rates of mice in hUCMSC-sEV/GelMA hydrogel group were significantly higher than those in the other 3 groups (P<0.05); the wound healing rates of mice in GelMA hydrogel alone group and hUCMSC-sEV alone group were significantly higher than those in PBS group (P<0.05). On PID 8 and 12, the wound healing rates of mice in hUCMSC-sEV alone group were significantly higher than those in GelMA hydrogel alone group (P<0.05). On PID 12, the wounds of mice in hUCMSC-sEV/GelMA hydrogel group showed the best wound epithelization, loose and orderly arrangement of dermal collagen, and the least number of inflammatory cells, while the dense arrangement of dermal collagen and varying degrees of inflammatory cell infiltration were observed in the wounds of mice in the other 3 groups. Conclusions: hUCMSCs-sEVs can promote the migration and proliferation of HEKs, HDFs, and HUVECs which are related to skin wound healing, and slowly release in GelMA hydrogel. The hUCMSC-sEV/GelMA hydrogel as a wound dressing can significantly improve the healing speed of full-thickness skin defect wounds in mice.

[Effects of early debridement and conservative eschar removal followed by wound coverage with acellular dermal matrix in the treatment of children with deep burns]

Objective: To explore the effects of early debridement and conservative eschar removal followed by wound coverage with acellular dermal matrix (ADM), i.e., early surgery, in the treatment of children with deep burns. Methods: This study was a retrospective cohort study. From January 2017 to December 2022, 278 deep burned hospitalized children aged 1-7 years who met the inclusion criteria were admitted to Central Hospital Affiliated to Shandong First Medical University. According to the differences in treatment processes, 134 children who underwent early surgery+routine dressing change were enrolled in eschar removal+dressing change group (77 males and 57 females, aged 1 (1, 2) years), and 144 children who underwent only routine dressing change were enrolled in dressing change alone group (90 males and 54 females, aged 1 (1, 2) years). Fifty-one children without full-thickness burns in eschar removal+dressing change group were enrolled in eschar removal+dressing change group 1 (26 males and 25 females, aged 1 (1, 2) years), and 57 cases of the 83 children with full-thickness burns who did not undergo autologous skin grafting at the same time of early surgery (namely early skin grafting) in eschar removal+dressing change group were included in eschar removal+dressing change group 2 (37 males and 20 females, aged 1 (1, 2) years). Seventy-six children without full-thickness burns in dressing change alone group were included in dressing change alone group 1 (51 males and 25 females, aged 1 (1, 3) years), and 68 children with full-thickness burns in dressing change alone group were included in dressing change alone group 2 (39 males and 29 females, aged 1 (1, 2) years). For deep partial-thickness burn wounds and small full-thickness burn wounds in eschar removal+dressing change group, the eschar removal was performed on the basis of retaining a thin layer of denatured dermis so as to preserve the healthy tissue of the wound base, and ADM was applied to all wounds externally after eschar removal. For larger full-thickness burn wounds in this group, especially those located in the functional part of joints, eschar removal to the plane layer of viable tissue and early autologous skin grafting was needed. When the superficial wounds of children healed or tended to heal, the residual wounds were evaluated, and elective autologous skin grafting was performed if it was difficult to heal within 14 days. The healing time, intervention healing time, times of operation/dressing change, and times of intervention operation/dressing change in children with deep partial-thickness burn wounds of children in eschar removal+dressing change group, dressing change alone group, eschar removal+dressing change group 1, and dressing change alone group 1 were recorded. At the last follow-up (follow-up period was set to 7-12 months), the modified Vancouver scar scale (mVSS) scores of the most severe area of scar hyperplasia of healed deep partial-thickness burn wounds of 54 children in eschar removal+dressing change group and 48 children in dressing change alone group were recorded. The healing time and times of operation/dressing change of all burn wounds of children in eschar removal+dressing change group and dressing change alone group, and the healing time and times of operation/dressing change of full-thickness burn wounds of children in eschar removal+dressing change group 2 and dressing change alone group 2 were recorded. The incidences of wound infection, sepsis, fever, and fever after 5 days of burns in children of eschar removal+dressing change group and dressing change alone group during wound healing. Results: Compared with those in dressing change alone group, the healing time and intervention healing time were significantly shortened, and the times of operation/dressing change and times of intervention operation/dressing change were significantly reduced in children with deep partial-thickness burn wounds in eschar removal+dressing change group (with Z values of -11.00, -11.33, -12.64, and -11.65, respectively, P<0.05). Compared with those in dressing change alone group 1, the healing time and intervention healing time were significantly shortened, and the times of operation/dressing change and times of intervention operation/dressing change were significantly reduced in children with deep partial-thickness burn wounds in eschar removal+dressing change group 1 (with Z values of 6.57, 6.46, 8.04, and 6.57, respectively, P<0.05). At the last follow-up, the mVSS score of the most severe scar hyperplasia area of healed deep partial-thickness burn wounds of 54 children in eschar removal+dressing change group was 4.00 (3.00,5.00), which was significantly lower than 6.50 (5.00,7.00) of 48 children in dressing change alone group (Z =-4.67, P<0.05).Compared with those in dressing change alone group, the healing time was significantly shortened, and times of operation/dressing change was significantly reduced in all burn wounds in eschar removal+dressing change group (with Z values of -5.20 and -6.34, respectively, P<0.05). Compared with those in dressing change alone group 2, the healing time was significantly shortened, and times of operation/dressing change was significantly reduced in full-thickness burn wounds in eschar removal+dressing change group 2 (with Z values of -5.22 and -5.73, respectively, P<0.05). During wound healing, the probabilities of fever and fever after 5 days of burns in children of eschar removal+dressing change group were significantly lower than those in dressing change alone group (with χ2 values of 4.13 and 3.91, respectively, P<0.05); only 1 child in dressing change alone group developed sepsis, and there was no statistically significant difference in the wound infection rate of children in the two groups (P>0.05). Conclusions: For children with deep burns, early surgery, and early skin grafting or elective autologous skin grafting as needed, have better short-term and long-term effects than those without early surgery.

[Risk factors of cytomegalovirus infection in patients with failed corneal grafts]

Objective: To investigate the levels of cytomegalovirus (CMV) infection and associated risk factors in corneal transplant recipients who experienced transplant failure. Methods: This was a case-control study. Clinical data from 576 cases (576 eyes) of patients who underwent repeat corneal transplant surgery at the Department of Ophthalmology, Peking University Third Hospital, due to corneal transplant failure from January 2016 to May 2022 were collected. Of these, 305 were male and 271 were female, with a median age of 44.0 (0.7, 91.0) years. The CMV infection rate was analyzed based on the detection of CMV DNA in aqueous humor or corneal tissue during corneal transplant surgery. Patients were divided into the CMV group (CMV DNA positive) and the control group (herpes virus DNA negative). The main research indicators included the CMV infection rate, clinical characteristics, and risk factors in corneal transplant recipients. Chi-square tests and binary logistic analysis were used to compare differences between the two groups in general information, systemic diseases, ocular lesions, ocular surgical history, and local and systemic medications. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for each CMV infection risk factor. Results: The overall CMV infection rate was 21.9%(126/576), with annual rates ranging from 10.9% to 37.7% from 2016 to 2021. After applying inclusion and exclusion criteria, 378 patients were included in the control trial, with 126 in the CMV group and 252 in the control group. Statistically significant differences between the two groups were observed in systemic immune-related corneal lesions [CMV group: 38 (30.2%), control group: 26 (10.3%)], local immune and inflammatory corneal lesions [CMV group: 46 (36.5%), control group: 40 (15.9%)], congenital corneal opacity [CMV group: 46 (36.5%), control group: 48 (19.0%)] total number of corneal transplants (CMV group: 178 times, control group: 276 times), corneal deep neovascularization crossing the graft [CMV group: 104 (82.5%), control group: 68 (27.0%)] and severe opacity [CMV group: 44 (34.9%), control group: 30 (11.0%)]. Binary logistic regression analysis showed that systemic immune-related corneal lesions (OR=4.044, 95%CI 1.810-9.033, P<0.001), local immune and inflammatory corneal lesions (OR=3.554, 95%CI 1.569-8.052, P=0.002), congenital corneal opacity (OR=2.606, 95%CI 1.216-5.589, P=0.014), total number of corneal transplants (OR=3.206, 95%CI 1.753-5.864, P<0.001), corneal deep neovascularization crossing the graft (OR=8.347, 95%CI 3.967-17.559, P<0.001), and severe opacity (OR=3.063, 95%CI 1.221-7.682, P=0.017) were independent risk factors for CMV infection after corneal transplant. Conclusions: CMV infection was present in more than 1/5 of corneal transplant recipients who experienced transplant failure. CMV infection after corneal transplant may be related to immune rejection reactions and ocular inflammatory responses. Inflammatory corneal lesions associated with systemic or local immune abnormalities, congenital corneal opacity, and multiple corneal transplants may exacerbate the levels of inflammatory factors during the perioperative period of corneal transplant, increasing the risk of post-transplant CMV infection, leading to the infiltration of deep neovascularization and severe opacity in the cornea.

[Analysis of prognosis and influencing factors of No. 253 lymph node metastasis in descending colon, sigmoid colon, and rectal cancer: a multicenter study]

Objectives: To analyze the influencing factors of No. 253 lymph node metastasis in descending colon cancer, sigmoid colon cancer, and rectal cancer, and to investigate the prognosis of No. 253 lymph node-positive patients by propensity score matching analysis. Methods: A retrospective analysis was performed on clinical data from patients with descending colon cancer, sigmoid colon cancer, rectosigmoid junction cancer, and rectal cancer who underwent surgery between January 2015 and December 2019 from the Cancer Hospital of the Chinese Academy of Medical Sciences, China-Japan Friendship Hospital, Peking Union Medical College Hospital, General Hospital of the Chinese People's Liberation Army, and Peking University Cancer Hospital. A total of 3 016 patients were included according to inclusion and exclusion criteria, comprising 1 848 males and 1 168 females, with 1 675 patients aged≥60 years and 1 341 patients aged<60 years. Clinical and pathological factors from single center data were subjected to univariate analysis to determine influencing factors of No. 253 lymph node metastasis, using a binary Logistic regression model. Based on the results of the multivariate analysis, a nomogram was constructed. External validation was performed using data from other multicenter sources, evaluating the effectiveness through the area under the receiver operating characteristic curve and the calibration curve. Using data from a single center, the No. 253 lymph node-positive group was matched with the negative group in a 1∶2 ratio (caliper value=0.05). Survival analysis was performed using the Kaplan-Meier method and Log-rank test. The Cox proportional hazards model was used to determine independent prognostic factors. Results: (1) The tumor diameter≥5 cm (OR=4.496,95%CI:1.344 to 15.035, P=0.015) T stage (T4 vs. T1: OR=11.284, 95%CI:7.122 to 15.646, P<0.01), N stage (N2 vs. N0: OR=60.554, 95%CI:7.813 to 469.055, P=0.043), tumor differentiation (moderate vs. well differentiated: OR=1.044, 95%CI:1.009 to 1.203, P=0.044; poor vs. well differentiated: OR=1.013, 95%CI:1.002 to 1.081, P=0.013), tumor location (sigmoid colon vs. descending colon: OR=9.307, 95%CI:2.236 to 38.740, P=0.002), pathological type (mucinous adenocarcinoma vs. adenocarcinoma: OR=79.923, 95%CI:15.113 to 422.654, P<0.01; signet ring cell carcinoma vs. adenocarcinoma: OR=27.309, 95%CI:4.191 to 177.944, P<0.01), and positive vascular invasion (OR=3.490, 95%CI:1.033 to 11.793, P=0.044) were independent influencing factors of No. 253 lymph node metastasis. (2) The area under the curve of the nomogram prediction model was 0.912 (95%CI: 0.869 to 0.955) for the training set and 0.921 (95%CI: 0.903 to 0.937) for the external validation set. The calibration curve demonstrated good consistency between the predicted outcomes and the actual observations. (3) After propensity score matching, the No. 253 lymph node-negative group did not reach the median overall survival time, while the positive group had a median overall survival of 20 months. The 1-, 3- and 5-year overall survival rates were 83.9%, 61.3% and 51.6% in the negative group, and 63.2%, 36.8% and 15.8% in the positive group, respectively. Multivariate Cox analysis revealed that the T4 stage (HR=3.067, 95%CI: 2.357 to 3.990, P<0.01), the N2 stage (HR=1.221, 95%CI: 0.979 to 1.523, P=0.043), and No. 253 lymph node positivity (HR=2.902, 95%CI:1.987 to 4.237, P<0.01) were independent adverse prognostic factors. Conclusions: Tumor diameter ≥5 cm, T4 stage, N2 stage, tumor location in the sigmoid colon, adverse pathological type, poor differentiation, and vascular invasion are influencing factors of No. 253 lymph node metastasis. No. 253 lymph node positivity indicates a poorer prognosis. Therefore, strict dissection for No. 253 lymph node should be performed for colorectal cancer patients with these high-risk factors.

[Study on the mechanism of early pancreatic exocrine function changes in severely scalded rats]

Objective: To explore the mechanism of early pancreatic exocrine function changes in severely scalded rats. Methods: The experimental research methods was used. Eighty male Sprague-Dawley rats aged 7-8 weeks were divided into simple sham injury group (n=8), sham injury+cholecystokinin octapeptide (CCK8) group (n=8), severe scald+CCK8 group (n=32), and extremely severe scald+CCK8 group (n=32) by the random number table, which were treated accordingly. Immediately after injury of rats in the 2 sham injury groups and 1, 2, 3, and 7 days after injury of rats in the 2 scald groups, the improved methods including pancreatic duct puncture and catheterization were used to dynamically collect the pancreatic-bile juice (PBJ) of rats. The PBJ secretory volume within 1 h was recorded, and the content of pancreatic lipase, α-amylase, and trypsin in PBJ was detected by enzyme-linked immunosorbent assay (ELISA), and the number of samples was 8. The femoral venous blood was collected, and the concentrations of pancreatic lipase and α-amylase in serum were detected by standard colorimetry to reflect their activity (n=8). The pancreatic tissue was extracted, and the levels of interleukin-1β (IL-1β) and IL-6 in pancreatic tissue were detected by ELISA (n=8), the expression of hypoxia-inducible factor 1α (HIF-1α) in pancreatic tissue was detected by immunofluorescence method, and the histopathological changes in pancreatic tissue were observed by hematoxylin-eosin staining, the severity of pancreatic tissue injury in the 2 scald groups was evaluated by modified Schmidt method (n=6), and the ultrastructure of acinar cells in pancreatic tissue was observed by transmission electron microscopy. Data were statistically analyzed with analysis of variance for factorial design, Tukey test, independent sample t test, and least significant difference test. Results: Compared with the PBJ secretory volume (0.740±0.030) mL in the pancreatic tissue of rats in simple sham injury group within 1 h immediately after injury, the (0.823±0.033) mL in sham injury+CCK8 group was significantly increased (t=4.92, P<0.05). Compared with that of rats in sham injury+CCK8 group immediately after injury, the PBJ secretory volume of rats within 1 h in severe scald+CCK8 group ((0.681±0.024), (0.608±0.056), (0.525±0.025), and (0.720±0.044) mL) and extremely severe scald+CCK8 group ((0.540±0.025), (0.406±0.021), (0.475±0.036), and (0.690±0.018) mL) was significantly decreased on 1, 2, 3, and 7 days after injury (P<0.05). Compared with that in severe scald+CCK8 group, the PBJ secretory volume of rats within 1 h in extremely severe scald+CCK8 group was significantly decreased on 1 and 2 days after injury (P<0.05). Compared with that of rats in simple sham injury group immediately after injury, the content of pancreatic lipase, α-amylase, and trypsin in PBJ of rats in sham injury+CCK8 group immediately after injury was significantly increased (with t values of 4.56, 3.30, and 4.99, respectively, P<0.05). Compared with that of rats in sham injury+CCK8 group immediately after injury, the content of pancreatic lipase and α-amylase in PBJ of rats in severe scald+CCK8 group and extremely severe scald+CCK8 group was significantly decreased on 1, 2, 3, and 7 days after injury (P<0.05), the trypsin content in PBJ of rats in extremely severe scald+CCK8 group was significantly decreased on 2 days after injury (P<0.05). Compared with that in severe scald+CCK8 group, the content of pancreatic lipase in PBJ of rats in extremely severe scald+CCK8 group was significantly decreased on 1, 2, and 3 days after injury (P<0.05), and the content of α-amylase and trypsin in PBJ was significantly decreased on 1 and 2 days after injury (P<0.05). There were no statistically significant differences in the activities of pancreatic lipase and α-amylase in serum of rats among the 4 groups at various time points after injury (P>0.05). Compared with that of rats in sham injury+CCK8 group immediately after injury, the levels of IL-1β in pancreatic tissue of rats in severe scald+CCK8 group on 1, 2, and 3 days after injury and in extremely severe scald+CCK8 group on 1, 2, 3, and 7 days after injury were significantly increased (P<0.05), and the levels of IL-6 in pancreatic tissue of rats in severe scald+CCK8 group and extremely severe scald+CCK8 group were significantly increased on 1, 2, 3, and 7 days after injury (P<0.05). Compared with that in severe scald+CCK8 group, the IL-1β level in pancreatic tissue of rats in extremely severe scald+CCK8 group was significantly increased on 2 and 3 days after injury (P<0.05), and IL-6 level in pancreatic tissue was significantly increased on 2 days after injury (P<0.05). The expression levels of HIF-1α in pancreatic tissue of rats in simple sham injury group and sham injury+CCK8 group immediately after injury were lower; and compared with that in sham injury+CCK8 group immediately after injury, the expression levels of HIF-1α in pancreatic tissue of rats in the 2 scald groups increased to a certain extent at different time points after injury, and the expression position was transited from the edge of the pancreatic tissue to the whole pancreas, the expression levels of HIF-1α in pancreatic tissue of rats in the 2 scald groups tended to be normal on 7 days after injury. Compared with that in simple sham injury group immediately after injury, the proportion of acinar cell cytoplasm in pancreatic tissue of rats in sham injury+CCK8 group was increased; and with the increase of time after injury, edema, hemorrhage, necrosis, and inflammatory infiltration appeared in pancreatic tissue of rats in the 2 scald groups. Compared with that in severe scald+CCK8 group, the scores of edema, inflammatory cell infiltration, bleeding, and necrosis in pancreatic tissue of rats in extremely severe scald+CCK8 group were increased to varying degrees at various time points after injury, and the scores of pancreatic tissue of rats in the 2 scald groups basically recovered to normal on 7 days after injury. Compared with that in simple sham injury group immediately after injury, the number of enzyme granules in acinar cells of pancreatic tissue of rats in sham injury+CCK8 group was increased, and with the increase of time after injury, the enzyme granules in acinar cells of rats in the 2 scald groups were gradually reduced basically. Conclusions: The exocrine functions of pancreas, such as synthesis and secretion of pancreatic enzymes, are decreased in the early stage in severely scalded rats. And the greater the scalded area, the more significant the decline of pancreatic exocrine function. This change may be related to hypoxic injury and inflammation in pancreatic tissue after severe scald.

A case report of extremely severe 93% total body surface area burns in a 5-year-old boy

BACKGROUND

Large surface area burns with concurrent severe burn sepsis are a rare phenomenon, particularly when the wounds are closed in a short timeframe.

CASE REPORT

This study describes a 5-year-old patient with 93% total body surface area (TBSA) burns and severe burn sepsis, who was managed through the use of a 54-day brickwork-mixed graft of self-allogeneic skin operation. The mechanisms of skin healing, in this case, are also discussed.

CONCLUSIONS

The brickwork-mixed graft of self-allogeneic skin may be an effective treatment option for patients with large surface area burns and severe burn sepsis. Further research is required to establish the generalizability of these findings. Early wound management and anti-infection measures are crucial in treating severe burns, and the clinical outcomes of the patient and the impact of the chosen treatment method on the patient's recovery and prognosis should be assessed.

[A cross-sectional survey on the allocation of nursing human resources in burn centers in China]

Objective: To investigate the allocation of nursing human resources in burn centers in China. Methods: A cross-sectional survey was conducted. Using a self-designed questionnaire, a survey was carried out from January to March 2022 to investigate the January to December 2021 status of 39 burn centers in China that met the inclusion criteria based on six strategic regions and other regions, including the hospital grade and the region, the number of nurses and opening beds in the burn centers and burn intensive care units (BICUs), the age, working seniority in burn specialty, educational background, professional title, personnel employment, and turnover of nurses and training of newly recruited nurses in the burn centers. Results: This survey covered 30 provinces, municipalities, and autonomous regions in China (excluding Hong Kong Special Administrative Region, Macao Special Administrative Region, and Taiwan region of China). A total of 39 questionnaires were collected, all of which were valid. The 39 burn centers were located in 38 tertiary A hospitals and 1 tertiary B hospital, with 26 burn centers in strategic areas. The nurse/bed ratio of burn centers in the Greater Bay Area of Guangdong, Hong Kong, and Macao was the highest, while the nurse/bed ratio of burn centers in border ethnic minority area was the lowest. Except for the Chengdu-Chongqing Economic Circle, BICUs had been set up in burn centers in other regions. Among the 39 burn centers, the percentage of nurses aged 25 to 34 years was 51.21% (738/1 441), the percentage of nurses worked in burn specialty for less than 5 years was 31.16% (449/1 441), the percentage of nurses with bachelor's degree was 69.74% (1 005/1 441), and the percentage of nurses with nursing professional title was 44.14% (636/1 441), which were the highest. There were significant differences in the employment of nurses, the percentage of permanent nurses in burn centers in the collaborative development zone of Beijing-Tianjin-Hebei was 82.48% (113/137), while the percentage of permanent nurses in burn centers in important military strategic area was only 9.42% (34/361); the turnover rate of nurses was 9.03% (143/1 584), among which the turnover rate of nurses was 18.14% (80/441) in burn centers in important military strategic area. The training for newly recruited nurses in 39 burn centers was mainly based on the guidance of senior nurses and the pre-job education+specialist training. Conclusions: The burn nursing human resources in strategic areas in China are seriously insufficient and unevenly distributed, with unstable nurse team and lack of standardized specialist training. In particular, the nursing human resources in BICUs need to be equipped and supplemented urgently.

[A prospective study of the perforator evaluation and eccentric design of anterolateral thigh flap based on superficial fascial perforators assisted by modified computed tomography angiography]

Objective: To explore the preoperative whole perforator evaluation and intraoperative eccentric design of anterolateral thigh flap (ALTF) based on superficial fascial perforators by modified computed tomography angiography (CTA), and the clinical effects were observed. Methods: A prospective observational study was adopted. Twelve patients with oral and maxillofacial tumors and 10 patients with open injury of the upper limb with large soft tissue defects were hospitalized in the Department of Hand & Microsurgery and Department of Oral & Maxillofacial Surgery of Affiliated Hospital of Binzhou Medical University from January 2021 to July 2022, with 12 males and 10 females, aged from 33 to 75 years, an average age of 56.6 years. The wounds of the patients with oral and maxillofacial tumors were reconstructed by ALTF after the extensive tumor resection and radical cervical lymph node dissection in the same stage; the wounds of the patients with skin and soft tissue defect on the upper limb were covered by ALTF in stage Ⅱ after debridement in stage Ⅰ. After debridement, the area of wound was 3.5 cm×3.5 cm-25.0 cm×10.0 cm and the area of the required flap area was 4.0 cm×4.0 cm-23.0 cm×13.0 cm. Modified CTA scan was performed on the donor site of ALTF before the operation, with the parameters of modified CTA being set to mainly reduce the tube voltage and tube current, and increase the contrast dose and the dual phase scan. The acquired image data were sent to GE AW 4.7 workstation and adopted the volume reconstruction function for visual reconstruction and evaluation of the whole perforator. The information of perforator and source artery was marked on the body surface before operation according to the above evaluation. During the operation, an eccentric flap centered on the visible superficial fascia whole perforator was designed and cut according to the desired flap area and shape. The donor sites of the flap were repaired by direct sutures or full-thickness skin grafts. The total radiation dose was compared between the modified CTA scan and the traditional CTA scan. The distribution of outlet point of perforator of double thighs, the length and direction of superficial fascia perforators based modified CTA were recorded. The type, number, and origin of the target perforator, distribution of of outlet point of perforator, and the diameter, course, and branch of the source artery observed before the operation were compared with those observed during the operation. The healing of donor site wound and the survival of flaps in recipient site were observed after operation. The texture and appearance of flap, oral and upper limb functions, and the functions of femoral donor sites were followed up. Results: The total radiation dose of modified CTA scan was lower than that of the traditional CTA scan. A total of 48 perforators of double thighs were observed, among which, 31 (64.6%) perforators went outward and downward, 9 (18.8%) perforators went inward and downward, 6 (12.5%) perforators went outward and upward, and 2 (4.2%) perforators went inward and upward, and the average length of superficial fascia perforators was 19.94 mm. The preoperative observed type, number, and source of the perforator, the distribution of the outlet point of the perforator, diameter, course, and branches of the source artery were basically consistent with the intraoperative exploration. The types of 15 septocutaneous (including musculoseptocutaneous) perforators and 10 musculocutaneous perforators observed before the operation was consistent with intraoperative exploration. The distance between the mark of the surface perforator point and the actual exit point of the perforator during operation was (0.38±0.11) mm. All flaps survived without vascular crisis. The donor site wounds of 5 cases of skin grafting and 17 cases of direct suturing wounds healed well. The postoperative follow-up was 2 months to 1 year, with an average of 8.2 months, the flaps were soft and slightly bloated; the function of diet and mouth closing was accessible in patients with oral and maxillofacial tumors, the speech function was mildly impaired in patients with tongue cancer, but they could complete basic oral communication; the wrist and elbow joints and forearm rotation function were not significantly limited in patients with upper limb soft tissue injuries; there was no obvious tightness in the donor sites, and the function of the hip and knee joints was not limited. Conclusions: The whole perforator and even the subcutaneous perforator of the donor site of ALTF can be evaluated by modified CTA, and the flap can be used in oral or maxillofacial reconstruction and repair of skin and soft tissue defects of upper limbs to achieve good results. By clarifying the type, number, and source of the perforator, the distribution of the outlet point of the perforator, diameter, course, and branches of the source artery before the operation, the eccentric design of the ALTF based on the superficial fascia perforator was realized. This study has strong guiding value.

[Establishment and application of the ten-fold rehydration formula for emergency resuscitation of pediatric patients after extensive burns]

Objective: To investigate the scientificity and feasibility of the ten-fold rehydration formula for emergency resuscitation of pediatric patients after extensive burns. Methods: A retrospective observational study was conducted. The total burn area of 30%-100% total body surface area (TBSA) and body weight of 6-50 kg in 433 pediatric patients (250 males and 183 females, aged 3 months to 14 years) with extensive burns who met the inclusion criteria and admitted to the burn departments of 72 Class A tertiary hospitals were collected. The 6 319 pairs of simulated data were constructed after pairing each body weight of 6-50 kg (programmed in steps of 0.5 kg) and each total burn area of 30%-100% TBSA (programmed in steps of 1%TBSA). They were put into three accepted pediatric rehydration formulae, namely the commonly used domestic pediatric rehydration formula for burn patients (hereinafter referred to as the domestic rehydration formula), the Galveston formula, and the Cincinnati formula, and the two rehydration formulae for pediatric emergency, namely the simplified resuscitation formula for emergency care of patients with extensive burns proposed by the World Health Organization's Technical Working Group on Burns (TWGB, hereinafter referred to as the TWGB formula) and the pediatric ten-fold rehydration formula proposed by the author of this article--rehydration rate (mL/h)=body weight (kg) × 10 (mL·kg-1·h-1) to calculate the rehydration rate within 8 h post injury (hereinafter referred to as the rehydration rate). The range of the results of the 3 accepted pediatric rehydration formulae ±20% were regarded as the reasonable rehydration rate, and the accuracy rates of rehydration rate calculated using the two pediatric emergency rehydration formulae were compared. Using the maximum burn areas (55% and 85% TBSA) corresponding to the reasonable rehydration rate calculated by the pediatric ten-fold rehydration formula at the body weight of 6 and 50 kg respectively, the total burn area of 30% to 100% TBSA was divided into 3 segments and the accuracy rates of the rehydration rate calculated using the 2 pediatric emergency rehydration formulae in each segment were compared. When neither of the rehydration rates calculated by the 2 pediatric emergency rehydration formulae was reasonable, the differences between the two rehydration rates were compared. The distribution of 433 pediatric patients in the 3 previous total burn area segments was counted and the accuracy rates of the rehydration rate calculated using the 2 pediatric emergency rehydration formulae were calculated and compared. Data were statistically analyzed with McNemar test. Results: Substitution of 6 319 pairs of simulated data showed that the accuracy rates of the rehydration rates calculated by the pediatric ten-fold rehydration formula was 73.92% (4 671/6 319), which was significantly higher than 4.02% (254/6 319) of the TWGB formula (χ2=6 490.88,P<0.05). When the total burn area was 30%-55% and 56%-85% TBSA, the accuracy rates of the rehydration rates calculated by the pediatric ten-fold rehydration formula were 100% (2 314/2 314) and 88.28% (2 357/2 670), respectively, which were significantly higher than 10.98% (254/2 314) and 0 (0/2 670) of the TWGB formula (with χ2 values of 3 712.49 and 4 227.97, respectively, P<0.05); when the total burn area was 86%-100% TBSA, the accuracy rates of the rehydration rates calculated by the pediatric ten-fold rehydration formula and the TWGB formula were 0 (0/1 335). When the rehydration rates calculated by the 2 pediatric emergency rehydration formulae were unreasonable, the rehydration rates calculated by the pediatric ten-fold rehydration formula were all higher than those of the TWGB formula. There were 93.07% (403/433), 5.77% (25/433), and 1.15% (5/433) patients in the 433 pediatric patients had total burn area of 30%-55%, 56%-85%, and 86%-100% TBSA, respectively, and the accuracy rate of the rehydration rate calculated using the pediatric ten-fold rehydration formula was 97.69% (423/433), which was significantly higher than 0 (0/433) of the TWGB formula (χ2=826.90, P<0.05). Conclusions: The application of the pediatric ten-fold rehydration formula to estimate the rehydration rate of pediatric patients after extensive burns is more accurate and convenient, superior to the TWGB formula, suitable for application by front-line healthcare workers that are not specialized in burns in pre-admission rescue of pediatric patients with extensive burns, and is worthy of promotion.

[SENP1 induced protein deSUMO modification increased the chemotherapy sensitivity of endometrial cancer side population cells]

Objective: To inhibit the stemness maintenance potential of endometrial cancer and increase the sensitivity of endometrial cancer side population cells to chemotherapy drugs by inducing extensive deSUMOylation modification of proteins. Methods: Flow cytometry was used to sort and culture CD133(+) CD44(+) KLE endometrial cancer cell clone spheres. Protein expression level of small ubiquitin-related modifier 1 (SUMO1) and two stemness maintenance genes of tumor side population cells, octamer binding transcription factor-4 (Oct4) and sex determining region Y-box2 (Sox2), were detected by western blotting method. Lentivirus-mediated Sentrin/SUMO-specific proteases 1 (SENP1) gene was stably transfected into KLE side population cells. Western blotting was used to detect the protein expressions of SENP1, SUMO1, Oct4 and Sox2. The clone formation rate was compared between KLE side population cells with or without SENP1 overexpression. Flow cytometry was applied to detect cell cycle changes. 3-(4, 5-Dimethylthiazole-2)-2, 5-diphenyl-tetrazolium bromide (MTT) experiment and flow cytometry apoptosis method were used to detect the chemosensitivity of the side population of endometrial cancer cells to cisplatin. Tumor-bearing mouse models of endometrial cancer were established to detect the effect of SENP1 overexpression on the chemotherapy sensitivity of cisplatin. Results: Compared with CD133(-)CD44(-) KLE cells, CD133(+) CD44(+) KLE side population cells could form clonal spheres and express higher levels of SUMO1, Oct4 and Sox2 proteins (P<0.05). Compared with KLE side population cells that were not transfected with SENP1 gene, the expression level of SENP1 protein in KLE side population cells overexpressing SUMO1、Oct4 and Sox2 were lower. The clonal sphere formation rate was reduced from (25.67±5.44)% to (7.46±1.42)%, and cell cycle shifted from G(0)/G(1) phase to G(2) phase. IC(50) of cisplatin decreased from (55.46±6.14) μg/ml to (11.55±3.12) μg/ml, and cell apoptosis rate increased from (9.76±2.09)% to (16.79±3.44)%. Overexpression of SENP1 could reduce the tumorigenesis rate of KLE side population cells in vivo and increase their chemotherapy sensitivity to cisplatin (P<0.05). Conclusion: Overexpression of SENP1 can induce protein deSUMOylation modification, inhibit the stemness maintenance potential of endometrial cancer side population cells, and enhance their chemotherapy sensitivity, which provides a new reference for gene therapy of endometrial cancer.

[Application of pretrained model based on electronic medical record in recognition of acute respiratory infection]

Objective: To evaluate the recognition of acute respiratory infection (ARI) by a pretrained model based on electronic medical records (EMRs). Methods: 38 581 EMRs were obtained from Chongqing University Three Gorges Hospital in December 2021. Bidirectional encoder representation from transformers (BERT) pretrained model was used to identify ARI in EMRs. The results of medical professionals were considered as the gold standard to calculate the sensitivity, specificity, Kappa value, and area under the curve of the receiver operating characteristic (AUC). Results: There were 3 817 EMRs in the test set, with 1 200 ARIs. A total of 1 205 cases were determined as ARI by the model, with a sensitivity of 92.67% (1 112/1 200) and a specificity of 96.45% (2 524/2 617). The model identified ARI with similar accuracy in males and females (AUCs 0.95 and 0.94, respectively), and was more accurate in identifying ARI cases in those aged less than 18 than in adults 18-59 and adults 60 and older (AUCs 0.94, 0.89 and 0.94, respectively). The current model had a better identification of ARIs in outpatient patients than that in hospitalized patients, with AUCs of 0.74 and 0.95, respectively. Conclusion: The use of the BERT pretrained model based on EMRs has a good performance in the recognition of ARI cases, especially for the outpatients and juveniles. It shows a great potential to be applied to the monitoring of ARI cases in medical institutions.

[Research advances on the role and mechanism of epidermal stem cells in skin wound repair]

Epidermal stem cells play an pivotal role in skin self-renewal, wound repair, and re-epithelialization process. The emergence of new technologies and concepts such as single-cell sequencing and gene knockout further revealed a new mechanism of epidermal stem cells in epidermal self-renewal and wound repair, providing new ideas for wound repair. In this review, the mechanisms of proliferation, differentiation, and migration of epidermal stem cells are discussed. Combined with the analysis of researches on stem cell heterogeneity and cell plasticity, the physiological function of epidermal stem cells can be further understood. The application advances of epidermal stem cells in wound repair is also summarized, which would provide some advice for workers engaged in clinical and basic research on wound repair.

[Effects of collagen type ⅩⅦ α1 on epidermal stem cells in aging skin and the microRNA intervention mechanism]

Objective: To investigate the expression and function of collagen type ⅩⅦ α1 (COL17α1) in aging mouse skin and its effect on the stemness and proliferation of human epidermal stem cells (ESCs), and to explore the mechanism of related microRNA (miR) in intervening the expression of COL17α1 of human ESC. Methods: The method of experimental research was used. Twelve 2-month-old (young) and twelve 24-month-old (aged) male C57BL/6J mice were selected, and full-thickness skin samples from their upper back were taken for follow-up detection. After hematoxylin-eosin staining of the full-thickness skin samples of young mice and aged mice, the structure of the epidermis was observed and the thickness of the epidermis was measured; the morphology of epidermal basement membrane and hemidesmosomes were observed by transmission electron microscopy, and the hemidesmosomes were counted; the mRNA and protein expressions of COL17α1 were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blotting respectively, and the protein expression and distribution of COL17α1 was observed and detected by immunofluorescence method. The fresh foreskin tissue discarded after surgery was obtained from 3 healthy men aged 20-30 years who underwent circumcision at the Fourth Medical Center of PLA General Hospital, ESCs were extracted and well-grown cells were wsed for follow-up experiments. According to the random number table (the same grouping method below), ESCs were divided into blank control group, transfection reagent control group, empty vector plasmid group, and COL17α1 knockdown plasmid group with corresponding treatment. After 48 hours of culture, the mRNA expression of COL17α1 was detected by real-time fluorescent quantitative RT-PCR, the protein expressions of COL17α1 and cytokeratin 14 (CK14) were detected by Western blotting, and the cell proliferation level was detected by cell counting kit 8. miRs that might act on the 3' non-coding region of COL17α1 mRNA were screened through DIANA, miRTarBase, miRNAMap, TargetScan, and microRNA databases. The ESCs were divided into negative control group transfected with miR mimic negative control and each miR mimic group transfected with each of the previously screened miR mimics. Forty-eight hours after transfection, the protein expression of COL17α1 was detected by Western blotting. Based on the sequencing data set GSE114006 in Gene Expression Omnibus (GEO), the GEO2R tool was used to statistically analyze the expression of the previously screened miRs that could cause the reduction of COL17α1 protein expression in the skin of 30 young (18-25 years old) and 30 elderly (>70 years old) human skins. The full-thickness skin samples of young mice and aged mice were taken, and the expressions of increased miRs in the aforementioned aged human skin were detected by real-time fluorescent quantitative RT-PCR. Two batches of human ESCs were taken, the first batch was divided into COL17α1 wild type+miR-203b-3p negative control group and COL17α1 wild type+miR-203b-3p mimic group, and the second batch was divided into COL17α1 mutant+miR-203b-3p negative control group and COL17α1 mutant+miR-203b-3p mimic group. Each group of ESC was transfected with corresponding sequences respectively. Forty-eight hours later, the luciferase reporter gene detection kit was used to detect the gene expression level of COL17α1. The number of samples in the tissue experiment was 6, and the number of samples in the cell experiment was 3. Data were statistically analyzed with independent sample t test, one-way analysis of variance, least significant difference test or Dunnett's test, Mann-Whitney U test or Kruskal-Wallis H test. Results: Compared with those of young mice, the boundary between the epidermis and the dermis of the aged mice skin was blurred and the cell layers were less, and the thickness of epidermis was significantly thinner (Z=-2.88, P<0.01); the morphology of basement membrane was discontinuous, with less unevenly distributed hemidesmosomes at the epidermis-dermis junction, and the number of hemidesmosomes was significantly reduced (Z=-2.91, P<0.01); the mRNA and protein expression levels of COL17α1 in the skin of aged mice were significantly decreased (with t values of 10.61 and 6.85, respectively, P<0.01). Compared with those of young mice, the protein expression of COL17α1 in the basal layer of epidermis and the bulb of hair follicle in the skin of aged mice was significantly decreased (Z=-2.24, P<0.05). After 48 hours of culture, the protein expression levels of COL17α1 in ESCs of blank control group, transfection reagent control group, empty vector plasmid group, and COL17α1 knockdown plasmid group were 1.00±0.27, 1.12±0.21, 1.13±0.23, and 0.42±0.18, respectively. Compared with those of blank control group, the mRNA and protein expression levels of COL17α1, the protein expression level of CK14, and the proliferation level of ESCs in transfection reagent control group and empty vector plasmid group did not change significantly (P>0.05), while these indexes in COL17α1 knockdown plasmid group were significantly decreased (P<0.05 or P<0.01). miR-203a-3p, miR-203b-3p, miR-512-5p, miR-124-3p, miR-28-5p, miR-590-3p, and miR-329-5p might bind to the 3' non-coding region of COL17α1 mRNA. Forty-eight hours after transfection, compared with 1.000±0.224 in negative control group, the protein expression level of COL17α1 in ESCs of miR-329-5p mimic group, miR-203b-3p mimic group, and miR-203a-3p mimic group decreased significantly (0.516±0.188, 0.170±0.025, and 0.235±0.025, with t values of 3.17, 5.43, and 5.07, respectively, P<0.05 or P<0.01). Only the expression level of miR-203b-3p in the skin of the elderly was significantly higher than that of the young (t=3.27, P<0.01). The expression level of miR-203b-3p in the skin of aged mice was significantly higher than that of young mice (Z=-2.88, P<0.01). Forty-eight hours after transfection, the gene expression level of COL17α1 in ESCs of COL17α1 wild type+miR-203b-3p mimic group was significantly lower than that of COL17α1 wild type+miR-203b-3p negative control group (t=7.66, P<0.01). The gene expression level of COL17α1 in ESCs of COL17α1 mutant+miR-203b-3p mimic group was similar to that of COL17α1 mutant+miR-203b-3p negative control group (P>0.05). Conclusions: The mRNA and protein expression levels of COL17α1 decrease with age increasing in mice, which may lead to the detachment of mouse ESC from the epidermal basement membrane. Decreased expression of COL17α1 can inhibit the expression of CK14 and ESC proliferation, which may be responsible for the thinning of the epidermis and slower wound healing in aged human skin. The increased expression of miR-203b-3p in aged mouse skin can target and bind to the 3' non-coding region of COL17α1 mRNA, hindering the post-transcriptional translation process, thus resulting in decreased COL17α1 protein expression.

[Clinical characteristics and diagnosis and treatment strategies of patients with severe traumatic aortic injury]

Objective: To investigate the clinical characteristics and diagnosis and treatment strategies of patients with severe traumatic aortic injury (TAI). Methods: A total of 25 patients with TAI, who hospitalized in our hospital between August 2005 to March 2021 and underwent thoracic aortic endovascular repair (TEVAR), were included in this retrospective study. According to the time from admission to TEVAR, the patients were divided into emergency TEVAR group (14 cases, TEVAR within 24 h of admission) and elective TEVAR group (11 cases, patients underwent surgery or fracture reduction and fixation first for serious injuries and then underwent TEVAR more than 24 h after admission). The general clinical data of patients, injury severity score (ISS), time from admission to intervention, total hospital stay, the proportion of closed chest drainage and the proportion of abdominal organ repair were obtained and compared. Clinical follow-up and 1-year postoperative aortic computed tomography angiography (CTA) were performed on the patients. Death, the occurrence of aortic adverse events and injury recovery were followed up and recorded. Results: The mean age of these 25 TAI patients was (41.4±14.4) years, 20 patients were males (80.0%). 21 patients (84.0%) had persistent chest and back pain, 17 (68.0%) had pleural effusion and 5 (20.0%) had mediastinal hematoma. The injury severity score (ISS) was significantly higher in the elective TEVAR group than in the emergency TEVAR group (24.9±14.4 vs. 35.5±9.3, P=0.044). The time from admission to intervention ((1.0±0.0) d vs. (3.4±0.9) d, P<0.001], the time from admission to TEVAR ((1.0±0.0) d vs. (11.5±13.8) d, P=0.030) and total hospital stay ((6.1±2.3) d vs. (26.8±7.7) d, P<0.001) were significantly longer in elective TEVAR group than in emergency TEVAR group. The proportion of thoracic closed drainage was significantly lower in the elective TEVAR group than in the emergency TEVAR group (9 (64.3%) vs. 2 (18.2%), P=0.042). The proportion of abdominal organ repair was significantly higher than in the emergency TEVAR group (0 vs. 4 (36.4%), P=0.026). All of 25 patients were discharged alive and followed up for (84.0±30.5) months. All patients survived and completed 1-year postoperation CTA. There were no aortic adverse events occurred, and no complications after surgery, and the fractures and organ injuries healed well. Conclusions: The clinical characteristics of severe TAI are acute multi-injuries combined with persistent chest and/or back pain, pleural effusion, and mediastinal hematoma. Timely diagnosis and treatment are important factors for the outcome. The treatment strategy for multi-injuries should give priority to dealing with life-threatening injuries. TEVAR is the primary treatment strategy for severe TAI and is related to satisfactory outcomes.

[Characteristics and risk factors of functional constipation in children aged 0-4 years in Xi 'an]

Objective: To investigate the epidemiology, characteristics and risk factors of functional constipation (FC) in children aged 0-4 years in Xi'an. Methods: From October, 2020 to June, 2021, a prevalence survey was conducted among 2 615 children aged 0-4 years in Xi'an by group sampling. The related factors of FC were investigated by questionnaire designed based on Rome Ⅳ diagnostic criteria.The children were divided into FC group and non-FC group. The prevalence, symptoms and signs of FC were analyzed, and its risk factors were analyzed by multivariate Logistic regression. Results: A total of 2 985 valid questionnaires were handed out, and 2 711 (90.8%) were received back. A total of 2 615 questionnaires were valid, with an effective rate of 96.5%. There were 1 338 males (51.2%) and 1 277 females (48.8%). There were 260 cases in FC group and 2 355 cases in non-FC group. The prevalence of FC in children aged 0-4 years in Xi 'an was 10.6%.There were significant differences in FC prevalence among children of different ages and sex (χ²=14.58,4.39, both P<0.05), but not in urban or rural residence (χ²=3.29, P=0.070). The main symptoms of FC group in the last month were large-diameter feces (73.5%, 191/260), painful defecation or dry and hard defecation (65.8%, 171/260). In the last month, FC group had higher incidences of the Bristol type 1, 2 and 3 stool, fecal retention, prolonged defecation, abdominal pain and incomplete defecation compared with non-FC group, with statistical significance (all P<0.05). Parental history of childhood constipation (OR=2.13, 95%CI 1.55-2.92), fever in the last month (OR=1.86, 95%CI 1.32-2.63), history of constipation (OR=3.24, 95%CI 2.46-4.26) and taking probiotics in the last month (OR=1.45, 95%CI 1.11-1.91) were risk factors of FC in children aged 0-4 years. Stratified with age, the results showed that complementary feeding earlier than 5 months of age or later than 6 months of age (OR=2.42, 95%CI 1.13-5.20), dry stools during the complementary feeding (OR=11.27, 95%CI 5.15-24.66), history of constipation (OR=2.29, 95%CI 1.23-4.29) and taking probiotics in the last month (OR=1.88, 95%CI 1.10-3.23) were risk factors of FC in children aged 0-<1 year, and breastfeeding (OR=0.53, 95%CI 0.29-0.94) was a protective factor of FC in children aged 0-<1 year. Family members' recent constipation history (OR=2.02, 95%CI 1.06-3.85) and past history of constipation (OR=3.06, 95%CI 1.74-5.38) were FC risk factors for children aged 1-<2 years. Parental history of childhood constipation (OR=3.12, 95%CI 2.00-4.85), frequency of eating vegetables less than 3 times per week (OR=3.28, 95%CI 2.00-5.38), history of constipation (OR=3.66, 95%CI 2.42-5.53) and taking antibiotics in the last month (OR=1.65, 95%CI 1.06-2.55) were risk factors for FC in children aged 2-4 years. Conclusions: FC in children aged 0-4 years in Xi'an is mainly manifested with large-diameter feces and painful defecation or dry and hard defecation in the last month. It is associated with a variety of risk factors, which are different in different age groups.

[Quality of life and influencing factors of postoperative accelerated rehabilitation of esophageal cancer patients]

Objective: To explore the quality of life and its influencing factors of enhanced recovery after surgery (ERAS) of esophageal cancer patients. Methods: The quality of life of 134 esophageal cancer patients was assessed using the quality of life assessment scale (EORTC QLQ-C30) developed by the European Cancer Research and Treatment Organization. Student's t test, One-way ANOVA and multiple linear regression statistical methods were used to analyze the effects of sociodemographic and clinical characteristics on patients' quality of life. Results: The overall score of quality of life (74.00) was lower than that of the general population (75.30). However, the scores of emotion and cognition in function dimension (93.97 and 95.77) were better than those of the general population (82.80 and 86.50). The results of fatigue, pain, insomnia and constipation in symptom dimension (14.18, 10.94, 11.69 and 5.72) were better than those of the general population (28.80, 20.50, 20.40 and 10.70). The pathological stage, body mass index and dietary were independent influencing factors for the quality of life of patients with esophageal cancer (P<0.05). Conclusions: ERAS can partially improve the quality of life of esophageal cancer patients. More attention should be paid to the esophageal cancer patients after surgery and take targeted measures to improve their quality of life.

[Mechanism of cleft palate in C57BL/6N mice induced by 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin]

Objective: To explore the molecular mechanism of cleft palate in mice induced by 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD). Methods: The pregnant mice were randomly divided into TCDD-treated group (n=42) and control group (n=42). TCDD-treated group was given by gavage a single dose of TCDD (64 μg/kg) at 8: 00 AM on gestation day 10 (GD10) and the control group was given by gavage the isopyknic corn oil. At GD13-GD15, the fetal mice palate development was observed by HE staining. The mouse embryonic palatal mesenchymal cell proliferation was detected by 5-bromo-2-deoxyuridine (BrdU) immunofluorescence. The localization and expression of maternally expressed gene3 (MEG3) in mouse embryonic palatal mesenchymal cells was detected by situ hybridization and real-time PCR (RT-PCR). The key protein expressions of transforming growth factor-β (TGF-β)/Smad signaling pathway in mouse embryonic palatal mesenchyme were analyzed by Western blotting. The interaction of MEG3 and TGF-β receptor Ⅰ (TGF-βRⅠ) was examined by RNA binding protein immunoprecipitation (RIP). Results: At GD13 and GD14, compared with the control group, the ratio of BrdU-positive cells in the palatal mesenchyme of TCDD-treated fetuses decreased significantly (GD13, t=6.66, P=0.003; GD14, t=6.56, P=0.003). However, at GD15, the ratio of BrdU-positive cells was significantly increased (t=-5.98, P=0.004). MEG3 was mainly expressed in the nuclei of fetal mouse palatal mesenchymal cells, and the expression of MEG3 in TCDD group was significantly increased at GD13, GD14 and GD15(GD13, t=39.28, P=0.012; GD14, t=18.75, P=0.042; GD15, t=28.36, P=0.045). At GD14, TCDD decreased the levels of p-Smad2 and Smad4 in embryonic palate mesenchymal cells (p-Smad2, t=9.48, P=0.001;Smad4, t=63.10, P=0.001), whereas the expression of Smad7 was significantly increased at GD14 (t=30.77, P<0.001). The results of the RIP experiment showed that the amount of TGF-βRⅠ-bound MEG3 in mouse embryonic palatal mesenchymal cells in the TCDD group (23.940±1.301) was higher than that in the control group (8.537±1.523)(t=24.55, P<0.001). Conclusions: MEG3 is involved in the suppression of mouse embryonic palatal mesenchymal cell proliferation, functioning at least in part via interacting with the TGF-βRⅠ protein and thereby suppressing Smad signaling in the context of TCDD induced cleft palate.

[Multicenter real-world study on safety and efficacy of neoadjuvant therapy in combination with immunotherapy for colorectal cancer]

Objective: To provide reference and evidence for clinical application of neoadjuvant immunotherapy in patients with colorectal cancer through multicenter large-scale analysis based on real-world data in China. Methods: This was a retrospective multicenter case series study. From January 2017 to October 2021, data of 94 patients with colorectal cancer who received neoadjuvant immunotherapy in Peking University Cancer Hospital (55 cases), Union Hospital of Tongji Medical College of Huazhong University of Science and Technology (19 cases), Sun Yat-sen University Cancer Center (13 cases) and Changhai Hospital of Navy Medical University (7 cases) were retrospectively collected, including 48 males and 46 females. The median age was 58 years. Eighty-one cases were rectal cancer and 13 cases were colon cancer (2 cases of double primary colon cancer). Twelve cases were TNM staging II and 82 cases were stage III. Forty-six cases were well differentiated, 37 cases were moderately differentiated and 11 cases were poorly differentiated. Twenty-six patients (27.7%) with mismatch repair defects (dMMR) and microsatellite instability (MSI-H) were treated with immunotherapy alone, mainly programmed cell death protein-1 (PD-1); sixty-eight cases (72.3%) with mismatch repair proficient (pMMR) and microsatellite stability (MSS) were treated with immune combined with neoadjuvant therapy, mainly CapeOx (capecitabine+oxaliplatin) combined with PD-1 antibody plus long- or short-course radiotherapy, or PD-1 antibody combined with cytotoxic T lymphocyte associated antigen 4 (CTLA-4) antibody. Analysis and evaluation of adverse events during neoadjuvant immunotherapy were performed according to the National Cancer Institute Common Toxicity Standard version 3.0; the surgical complications were evaluated according to the Clavien-Dindo grading standard; the efficacy evaluation of neoadjuvant immunotherapy included the following indicators: major pathological remission (MPR) was defined as tumor regression induced by neoadjuvant therapy in pathology residual tumor ≤10%; pathological complete response (pCR) was defined as tumor regression induced by neoadjuvant therapy without residual tumor in pathology; the tumor response rate was disease control rate (DCR), namely the proportion of complete response (CR), partial response (PR) and stable disease (SD) in the whole group; the objective response rate (ORR) was CR+PR. Results: The median cycle of neoadjuvant immunotherapy was 4 (1-10) in whole group, and the incidence of immune-related adverse reactions was 37.2% (35/94), including 35 cases (37.2%) of skin-related adverse reactions, 21 cases (22.3%) of thyroid dysfunction and 8 cases (8.5%) of immune enteritis, of which grade III or above accounted for 1.1%. The median interval between completion of neoadjuvant therapy and surgery was 30 (21-55) days. There were 81 cases of radical resection of rectal cancer, 11 cases of radical resection of colon cancer, and 2 cases of colon cancer combined with other organ resection. The primary tumor resection of all the patients reached R0. The incidence of surgical-related complications was 22.3% (21/94), mainly anastomotic leakage (4 cases), pelvic infection (4 cases), abdominal effusion (3 cases), anastomotic stenosis (3 cases ) and abdominal and pelvic hemorrhage (2 cases). Grade I-II complications developed in 13 cases (13.8%), grade III and above complications developed in 8 cases (8.5%), no grade IV or above complications were found. During a median follow-up of 32 (1-46 ) months, DCR was 98.9% (93/94), ORR was 88.3 % (83/94), pCR was 41.5% (39/94), MPR was 60.6% (57/94). The pCR rate of 26 patients with dMMR and MSI-H undergoing simple immunotherapy was 57.7% (15/26), and MPR rate was 65.4% (17/26). The pCR rate of 68 pMMR and MSS patients undergoing combined immunotherapy was 35.3%(24/68), and MPR rate was 58.8% (40/68). Conclusions: Neoadjuvant immunotherapy has favorable tumor control rate and pathological remission rate for patients with initial resectable colorectal cancer. The incidences of perioperative adverse reactions and surgical complications are acceptable.

[Establishment and application of the tenfold rehydration formula for emergency resuscitation of adult patients after extensive burns]

Objective: To explore the scientificity and feasibility of the tenfold rehydration formula for emergency resuscitation of adult patients after extensive burns. Methods: A retrospective observational study was conducted. The total burn area (30%-100% total body surface area (TBSA)) and body weight (45-135 kg) of 170 adult patients (135 males and 35 females, aged (42±14) years) with extensive burns admitted to the Fourth Medical Center of PLA General Hospital from December 2016 to December 2019 were collected. The 6 461 pairs of simulated data obtained after pairing each body weight in 45 to 135 kg (programmed in steps of 1 kg) with each area in 30% to 100% TBSA (programmed in steps of 1%TBSA) were plugged into four recognized rehydration formulas--Parkland's formula, Brooke's formula, the 304th PLA Hospital formula, and the Third Military Medical University formula and two emergency rehydration formulas--the simplified first aid resuscitation plan for extensive burn patients proposed by the World Health Organization's Technical Working Group on Burns (TWGB, hereinafter referred to as the TWGB formula) and the tenfold rehydration formula proposed by the author of this article to calculate the rehydration rate within 8 hours after injury (hereinafter referred to as the rehydration rate), with results being displayed by a programming step of 10%TBSA for the total burn area. Taking the calculation results of four recognized rehydration formulas as the reasonable rehydration rate, the accuracy of rehydration rates calculated by two emergency rehydration formulas were calculated and compared. The body weight of 45-135 kg was divided into three segments by the results of maximum body weight at a reasonable rehydration rate calculated by the tenfold rehydration formula when the total burn area was 30% and 100% TBSA, respectively. The accuracy of rehydration rate calculated by two emergency rehydration formulas in each body weight segment was compared. When the rehydration rates calculated by two emergency rehydration formulas were unreasonable, the differences in rehydration rates between the two were compared. Statistical distribution of the aforementioned three body weight segments in the aforementioned 170 patients was counted. Using the total burn area and body weight data of the aforementioned 170 patients, the accuracy of rehydration rate calculated by two emergency rehydration formulas was calculated and compared as before. Data were statistically analyzed with McNemar test. Results: When the total burn area was 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100% TBSA, respectively, and the body weight was 45-135 kg, the rehydration rates calculated by two emergency rehydration formulas did not exceed the maximum of the calculated results of four recognized rehydration formulas; the rehydration rate calculated by the TWGB formula did not change accordingly with total burn area, while the rehydration rate calculated by the tenfold rehydration formula did not change accordingly with body weight. Substituting 6 461 pairs of simulated data showed that the accuracy of rehydration rate calculated by the tenfold rehydration formula was 43.09% (2 784/6 461), which was significantly higher than 2.07% (134/6 461) of the TWGB formula, χ2=2 404.80, P<0.01. When the body weights were 45-62 kg and 63-93 kg, the accuracy rates of rehydration rate calculated by the tenfold rehydration formula were 100% (1 278/1 278) and 68.42% (1 506/2 201), respectively, which were significantly higher than 0 (0/1 278) and 0.05% (1/2 201) of the TWGB formula, χ2=1 276.00, 1 501.01, P<0.01; when the body weight was 94-135 kg, the accuracy rate of rehydration rate calculated by the tenfold rehydration formula was 0 (0/2 982), which was significantly lower than 4.46% (133/2 982) of the TWGB formula, χ2=131.01, P<0.01. When the rehydration rates calculated by two emergency rehydration formulas were both unreasonable, the rehydration rate calculated by the tenfold rehydration formula was greater than that calculated by the TWGB formula in most cases, accounting for 79.3% (2 808/3 543). Among the 170 patients, the proportions of those weighing 45-62, 63-93, and 94-135 kg were 25.29% (43/170), 65.88% (112/170), and 8.82% (15/170), respectively. Among the 170 patients, the accuracy rate of rehydration rate calculated by the tenfold rehydration formula was 69.41% (118/170), which was significantly higher than 3.53% (6/170) of the TWGB formula, χ2=99.36, P<0.01. Conclusions: Applying the tenfold rehydration formula to calculate the emergency rehydration rate in adults after extensive burns is simpler than four recognized rehydration formulas, and is superior to the TWGB formula. The tenfold rehydration formula is suitable for the front-line medical staffs that are not specialized in burns in pre-admission rescue of adult patients with extensive burns, which is worth popularizing.

[Drug-resistant gene polymorphisms in Plasmodium falciparum isolated from Bioko Island, Equatorial Guinea in 2018 and 2019]

OBJECTIVE

To investigate the genetic polymorphisms of Plasmodium falciparum multidrug resistance protein 1 (PfMDR1), chloroquine resistance transporter (PfCRT) and Kelch 13 (PfK13) genes in Bioko Island, Equatorial Guinea, so as to provide insights into the development of the malaria control strategy in local areas.

METHODS

A total of 85 peripheral blood samples were collected from patients with Plasmodium falciparum infections in Bioko Island, Equatorial Guinea in 2018 and 2019, and genomic DNA was extracted. The PfMDR1, PfCRT and PfK13 genes were amplified using a nested PCR assay. The amplification products were sequenced, and the gene sequences were aligned.

RESULTS

There were no mutations associated with artemisinin resistance in PfK13 gene in Bioko Island, Equatorial Guinea, while drug-resistant mutations were detected in PfMDR1 and PfCRT genes, and the proportions of PfMDR1_N86Y, PfMDR1_Y184F and PfCRT_K76T mutations were 35.29% (30/85), 72.94% (62/85) and 24.71% (21/85), respectively.

CONCLUSIONS

There are mutations in PfMDR1, PfCRT and PfK13 genes in P. falciparum isolates from Bioko Island, Equatorial Guinea.

[Research advances on application of single-cell RNA sequencing in islet cell biology]

After the first single-cell RNA sequencing of human islet in 2016, a large number of analysis of RNA sequencing at single-cell level on mouse and human islets emerged, which has brought new progress to the research of islet cell biology. It has been proved that single-cell RNA sequencing can characterize rare types of endocrine cells, find the cellular heterogeneity of typical endocrine cells and new cell subtypes, analyze the differences of endocrine cells among species, and describe different states of various types of islet cells in developmental processes and metabolic diseases more accurately. Although the detection efficiency of single-cell RNA sequencing for low abundance transcripts is relatively low at present, with the improvement of technology and the progress of analytical methods, this technology will undoubtedly become a powerful tool to explore the cellular heterogeneity, development, and biological characteristics of metabolic diseases.

The dual role of anti-viral therapy in the treatment of Coronavirus disease 2019

OBJECTIVE

Coronavirus disease 2019 (COVID-19) has become a worldwide public health emergency; unfortunately, there is currently no treatment for improving outcomes or reducing viral-clearance times in infected patients. The aim of the present study was to evaluate the efficacy of interferon (IFN) with or without lopinavir and ritonavir as antiviral therapeutic option for treating COVID-19 infection.

PATIENTS AND METHODS

The present study enrolled 148 patients that received either standard care, treatment with IFN alfa-2b, or IFN alfa-2b combined with lopinavir plus ritonavir. Viral testing was performed using Reverse-Transcription Polymerase Chain Reaction (RT-PCR).

RESULTS

There was no significant difference in the viral-clearance time at 28 days after treatment between patients receiving standard care and those receiving anti-viral treatments. However, the average viral-clearance time of patients receiving standard care (14 days) was shorter than that for patients receiving IFN alfa-2b or IFN alfa-2b combined with lopinavir plus ritonavir (15.5 or 17.5 days) (p<0.05). Patients treated with IFN alfa-2b within five days or IFN alfa-2b combined with lopinavir plus ritonavir after three days of symptoms exhibited shorter viral-clearance times than the other groups (p<0.05). Moreover, viral-clearance times were significantly longer in patients receiving standard care or anti-viral treatment 5 days after symptoms appeared than those of patients who received these treatments within five days of symptom onset (p<0.05).

CONCLUSIONS

Early symptomatic treatment is most critical for maximizing amelioration of COVID-19 infection. Anti-viral treatment might have complicated effect on viral-clearance.

[A pathological report of three COVID-19 cases by minimal invasive autopsies]

Objective: To investigate the pathological characteristics and the clinical significance of novel coronavirus (2019-nCoV)-infected pneumonia (termed by WHO as coronavirus disease 2019, COVID-19). Methods: Minimally invasive autopsies from lung, heart, kidney, spleen, bone marrow, liver, pancreas, stomach, intestine, thyroid and skin were performed on three patients died of novel coronavirus pneumonia in Chongqing, China. Hematoxylin and eosin staining (HE), transmission electron microcopy, and histochemical staining were performed to investigate the pathological changes of indicated organs or tissues. Immunohistochemical staining was conducted to evaluate the infiltration of immune cells as well as the expression of 2019-nCoV proteins. Real time PCR was carried out to detect the RNA of 2019-nCoV. Results: Various damages were observed in the alveolar structure, with minor serous exudation and fibrin exudation. Hyaline membrane formation was observed in some alveoli. The infiltrated immune cells in alveoli were majorly macrophages and monocytes. Moderate multinucleated giant cells, minimal lymphocytes, eosinophils and neutrophils were also observed. Most of infiltrated lymphocytes were CD4-positive T cells. Significant proliferation of type Ⅱ alveolar epithelia and focal desquamation of alveolar epithelia were also indicated. The blood vessels of alveolar septum were congested, edematous and widened, with modest infiltration of monocytes and lymphocytes. Hyaline thrombi were found in a minority of microvessels. Focal hemorrhage in lung tissue, organization of exudates in some alveolar cavities, and pulmonary interstitial fibrosis were observed. Part of the bronchial epithelia were exfoliated. Coronavirus particles in bronchial mucosal epithelia and type Ⅱ alveolar epithelia were observed under electron microscope. Immunohistochemical staining showed that part of the alveolar epithelia and macrophages were positive for 2019-nCoV antigen. Real time PCR analyses identified positive signals for 2019-nCoV nucleic acid. Decreased numbers of lymphocyte, cell degeneration and necrosis were observed in spleen. Furthermore, degeneration and necrosis of parenchymal cells, formation of hyaline thrombus in small vessels, and pathological changes of chronic diseases were observed in other organs and tissues, while no evidence of coronavirus infection was observed in these organs. Conclusions: The lungs from novel coronavirus pneumonia patients manifest significant pathological lesions, including the alveolar exudative inflammation and interstitial inflammation, alveolar epithelium proliferation and hyaline membrane formation. While the 2019-nCoV is mainly distributed in lung, the infection also involves in the damages of heart, vessels, liver, kidney and other organs. Further studies are warranted to investigate the mechanism underlying pathological changes of this disease.

[Analysis of clinical, pathological features and therapeutic treatments in predicting prognosis of elderly glioblastomas]

Objective: This study was designed to investigate prognostic factors and the potential relationship between the expression of Ki67 and IDH of glioblastoma in the elderly (≥ 65 years old) and the clinical factors such as gender, the KPS score and treatments including surgical resection, radiotherapy and chemotherapy and the prognosis of such patients. Methods: Fifty-four elderly patients (≥ 65 years old) with glioblastoma admitted to the First Affiliated Hospital of Zhengzhou University from 2013 to 2018 were enrolled in this study. The expression of Ki67 was detected by immunohistochemical SP method and the mutation of IDH was detected by Sanger sequencing. Finally, statistical analysis was performed to determine whether Ki67, the mutation of IDH, gender, the KPS score and the extent of resection, radiotherapy and chemotherapy were associated with the clinical prognosis of the patients. Results: Of the 54 elderly patients with glioblastoma, none was detected with IDH mutation. Univariate analysis showed that Ki67(P=0.033), the KPS score (P=0.008), the extent of resection (P<0.001) were factors influencing the prognosis of elderly patients with glioblastoma. Patients receiving postoperative adjuvant radiotherapy (P=0.002) and chemotherapy (P=0.034) had longer survival time. There was no significant correlation between gender (P=0.467) and prognosis. Multivariate analysis demonstrated that radiotherapy (OR 2.446, P=0.009) and the extent of resection (OR 6.976, P<0.001) were independent prognostic factors. Conclusions: No IDH mutation was detected in all the patients in this study, indicating that IDH mutation is indeed rare in elderly glioblastoma, which suggests that geriatric population often harbor a molecular phenotype with poor prognosis. Ki67, KPS score, the extent of resection, radiotherapy and chemotherapy were the factors influencing the prognosis of patients.

[Spectomycin B1 induces VEGFR2 de-SUMO modification to inhibit angiogenesis in nasopharyngeal carcinoma]

Objective:To explore the new mechanism of spectomycin B1 in inhibiting angiogenesis of nasopharyngeal carcinoma and to provide a theoretical basis for targeted gene therapy of nasopharyngeal carcinoma. Method:Human nasopharyngeal carcinoma CNE1 cells were divided into two groups, the control group and spectomycin B1 group. Western blot was used to detect the expression levels of small ubiquitin-related modified protein（SUMO） 1 and vascular endothelial growth factor receptor 2（VEGFR2）. The angiogenesis assay was used to detect the angiogenic ability of CNE1 cells, and the apoptosis was detected by flow cytometry. The model of nasopharyngeal carcinoma-bearing mice was established, spectomycin B1 was administered, tumor volume and weight were measured, and protein expression of CD31 was detected by immunohistochemistry and microvessel density was compared. Result:Spectomycin B1 could reduce deSUMOylation of VEGFR2 protein by 4.05 times, significantly reduce the angiogenic ability of CNE1 cells, and increase the apoptosis rate by 20.68%. In the tumor-bearing mouse model, spectomycin B1 treatment could inhibit subcutaneous tumor growth rate and weight, and the blood vessel density decreased by 40.04%. Conclusion:Spectomycin B1 can inhibit neovascularization of nasopharyngeal carcinoma by inducing deSUMOylation of VEGFR2 protein.

[Resection of lumbar nerve sheath tumors via muscle-pedicle open-door laminoplasty approach]

Objective: To evaluate the efficacy and safety of resection of lumbar nerve sheath tumors via muscle-pedicle open-door laminoplasty approach. Methods: From March 2016 to June 2018, 6 patients (4 males and 2 females, average age (45±14) years) with lumbar spinal nerve sheath tumors received surgical treatment via muscle-pedicleopen-door laminoplasty approach in the Department of Spinal Surgery, the Affiliated Hospital of Qingdao University. The operation time, blood loss, cerebral spinal fluid (CSF) leakage, and pre- and post-operative Oswestry Disability Index (ODI) and low back and leg pain visual analogue scale (VAS) were recorded for all patients. Cobb angle of lumbar lordosis was measured on the standing lateral X-ray before and 6 months after surgery. Bone fusion was observed in computed tomography at six months after surgery. Results: Total tumor resection was achieved in all the 6 patients. The operation time was from 76 to 117 minutes (average, (102±15) minutes). The blood loss was from 160 to 280 ml (average, (256±24) ml). No CSF leakage was observed in this cohort.All patients were followed up for more than 6 months. ODI and VAS for low back and leg pain were much better at one month after operation than those before the operation(t=7.70, 8.63,11.31, all P<0.05). The Cobb angle of lumbar lordosis before operation and at six months after the operation were comparable in all six patients(t=0.70, P>0.05). Bone fusion was observed in computed tomography at six months after surgery. No bone necrosis or absorption, no lamina dislodgement or spinal stenosis was occurred. Conclusions: The muscle-pedicle open-door laminoplasty approach is proved effective and safe to incise nerve sheath tumors in the lumbar spine. Some blood supply of lamina can be kept intact to accelerate bone fusion.

[Hypoxia increases chemotherapy resistance in nasopharyngeal carcinoma via inducing CDK6 deSUMOylation]

Objective: To understand the mechanism of chemotherapy resistance in nasopharyngeal carcinoma under hypoxic conditions through the perspective of protein SUMOylation modification. Methods: Cobalt chloride (CoCl(2)) was used to establish the hypoxic model of human nasopharyngeal carcinoma CNE1 cells. Then, the cell cycle was detected by flow cytometry, and the expression level of small ubiquitin-related modifier(SUMO) and cyclin-dependent kinase 6 (CDK6) proteins were detected by western blotting. MTT assay was used to determine the median lethal dose (IC(50)) of cancer cells against cisplatin, and enzyme-linked immunosorbent assay (ELISA) was used to determine lactate dehydrogenase (LDH) level. Results: The cell cycle of CNE1 induced by hypoxia was arrested in G0/G1 phase.The results of Western blot showed that the protein expression level of CDK6 in CNE1 cells was lower than that in the control group (0.83±0.25 vs. 0.43±0.21, t=14.67, P=0.003). The protein level of conjugated SUMO1 was significantly lower than that in the control group (2.69±0.48 vs. 1.38±0.31, t=17.22, P=0.001), while the level of free SUMO1 protein was significantly higher than that in the control group (2.01±0.43 vs. 2.60±0.59, t=15.45, P=0.002).The LC50 of CNE1 cells in the control group was significantly lower than that in the hypoxic group (29.44 μg/ml vs. 97.72 μg/ml, t=12.79, P=0.001). After CNE1 cells received 50 μg/ml cisplatin for 48 h, the LDH content in the supernatant of the control group was significantly higher than that in the hypoxic group ((541.49±64.59) ng/ml vs. (234.67±41.03) ng/ml, t=11.94, P=0.007)). The apoptosis rate of CNE1 cells in the control group was significantly higher than that in the hypoxic group ((76.64±5.37)% vs. (32.84±4.77) ng/ml, t=8.49, P=0.003)). Conclusion: Hypoxia can dissociate the covalent modification of CDK6 and SUMO1, inhibit cell cycle and increase the chemotherapy resistance of nasopharyngeal carcinoma.

[IDH、TERT and 1p/19q predicting clinical outcomes in patients with anaplastic oligodendroglioma]

Objective: To investigate the prognostic values of IDH, TERT and 1p/19q in patients with anaplastic oligodendroglioma. Methods: In the study, 66 patients with pathological diagnosis of anaplastic oligodendroglioma were enrolled (The First Affiliated Hospital of Zhengzhou University 2011 to 2016 years). Kaplan-Meier method was used to calculate the survival rates. Log-rank was used to calculate the differences in group. Chi-square testwas used tocalculate the differences in common factor group. Cox regression model was used to conduct multivariate analysis. Results: The median survival time of IDH-wt and IDH-mt subgroups were 16.10 and 42.00 months with statistical significance (P=0.001). The median survival time of 1p/19q codeleted and 1p/19q noncodeleted subgroups were 42.00 and 22.40 months with statistical significance (P=0.012). IDH-mt and 1p/19q codeleted predicted better survivals compared with IDH-wt and 1p/19q noncodeleted (P=0.001). And IDH-mt and 1p/19q noncodeleted predicted better survivals compared with IDH-wt and 1p/19q noncodeleted (P=0.041), too. Multivariate survival analysis demonstrated that Molecular groups was an independent factor to evaluate the prognosis of anaplastic oligodendroglioma (P=0.008). Conclusion: IDH-mtand (or) 1p/19q codeletedpredicted better survivals in patients with anaplastic oligodendroglioma. IDH and 1p/19q deleted might be a biomarker for predicting prognosis of patients with anaplastic oligodendroglioma.

["Watch and wait" strategy after neoadjuvant therapy for rectal cancer: status survey of perceptions, attitudes and treatment selection in Chinese surgeons]

Objective: To understand the perceptions, attitudes and treatment selection of Chinese surgeons on the "watch and wait" strategy for rectal cancer patients after achieving a clinical complete response (cCR) following neoadjuvant chemoradiotherapy (nCRT). Methods: A cross-sectional survey was used in this study. Selection of subjects: (1) Domestic public grade III A (provincial and prefecture-level) oncology hospitals or general hospitals possessing the radiotherapy department and the diagnosis and treatment qualifications for colorectal cancer. (2) Surgeons of deputy chief physician or above. Using the "Questionnaire Star" online survey platform to create a questionnaire about cognition, attitude and treatment choice of the "watch and wait" strategy after cCR following nCRT for rectal cancer. The questionnaire contained 32 questions, such as the basic information of doctor, the current status of rectal cancer surgery, the management of pathological complete remission (ypCR) after nCRT for rectal cancer, the selection of examination items for diagnosis of cCR, the selection of suitable people undergoing "watch and wait" approach, the nCRT mode for promotion of cCR, the choice of evaluation time point, the willingness to perform "watch and wait" approach and the treatment choice, and the risk and monitoring of "watch and wait" approach. A total of 116 questionnaires were sent to the respondents via WeChat between January 31 and February 19, 2019. Statistical analysis was performed using Fisher's exact test for categorical variables. Results: Forty-eight hospitals including 116 surgeons meeting criteria were enrolled, of whom 77 surgeons filled the questionnaire with a response rate of 66.4%. "Watch and wait" strategy was carried out in 76.6% (59/77) of surgeons. Seventy surgeons (90.9%) were aware of the ypCR rate of rectal cancer after preoperative nCRT and 49 surgeons (63.6%) knew the 3-year disease-free survival of patients with ypCR in their own hospitals. Fifty-five surgeons (71.4%) believed that patients with ypCR undergoing radical surgery met the treatment criteria and were not over-treated. Three most necessary examinations in diagnosing cCR were colonoscopy (96.1%, 74/77), digital rectal examination (DRE) (90.9%,70/77) and DWI-MRI (83.1%, 64/77). Responders preferred to consider a "watch and wait" strategy for patients with baseline characteristics as mrN0 (77.9%, 60/77), mrT2 (68.8%, 53/77) and well-differentiated adenocarcinoma (68.8%, 53/77). Sixty-six surgeons (85.7%) believed that long-term chemoradiotherapy (LCRT) with combination or without combination of induction and/or consolidation of the CapeOX regimen (capecitabine + oxaliplatin) should be the first choice as a neoadjuvant therapy to achieve cCR. Forty-one surgeons (53.2%) believed that a reasonable interval of judging cCR after nCRT should be ≥ 8 weeks. Forty-four surgeons (57.1%) routinely, or in most cases, informed patient the possibility of cCR and proposed to "watch and wait" strategy in the initial diagnosis of patients with non-metastatic rectal cancer. Thirteen surgeons (16.9%) would take the "watch and wait" strategy as the first choice after the patient having cCR. Fifty-two surgeons (67.5%) would be affected by the surgical method, that was to say, "watch and wait" approach would only be recommended to those patients who would achieve cCR and could not preserve the anus or underwent difficult anus-preservation surgery. Sixteen surgeons (20.8%) demonstrated that "watch and wait" strategy would not be recommended to patients with cCR regardless of whether the surgical procedure involved anal sphincter. Eleven surgeons (14.3%) believed that the main risk of "watch and wait" approach came from distant metastasis rather than local recurrence or regrowth. Twenty-nine of surgeons (37.7%) did not understand the difference between "local recurrence" and "local regrowth" during the period of "watch and wait". Twenty-six surgeons (33.8%) thought that the monitoring interval for the first 3 years of "watch and wait" strategy was 3 months, and the follow-up monitoring interval could be 6 months to 5 years. Surgeons from cancer specialist hospitals had higher approval rate, notification rate, and referral rate of "watch and wait" strategy than those from general hospitals. Thirty-one surgeons (42.5%) considered that the difficulty and concern of carrying out "watch and wait" approach in the future was the disease progress leading to medical disputes. Twenty-six surgeons (35.6%) demonstrated that their concern was lack of uniform evaluation standard for cCR. Conclusions: Chinese surgeons seem to have inadequate knowledge of non-operative management for rectal cancer patients achieving cCR after nCRT and show relatively conservative attitudes toward the strategy. Chinese consensus needs to be formed to guide the non-operative management in selected patients. Chinese Watch & Wait Database (CWWD) is also needed to establish and provide more evidence for the use of alternative procedure after a cCR following nCRT.

[Preoperative prognostic nutritional index predicts clinical outcomes in patients with lower-grade gliomas]

Objective: To investigate the prognostic values of preoperative prognostic nutritional index (PNI) in patients with lower-grade gliomas. Methods: In the study, 379 patients with pathological diagnosis of lower-grade gliomas were enrolledwhich were confirmed in The First Affiliated Hospital of Zhengzhou University (2011-02 to 2016-05). Kaplan-Meier method was used to calculate the survival rates. log-rank was used to calculate the differences in group. Cox regression model was used to conduct multivariate analysis. Results: The cutoff value of PNI was 46.70. The median survival time of PNI≤47.80 and PNI>47.80 subgroups were 46.76 and 67.37 months with statistical significance (P<0.001). High PNI predicted a better survival rate. Multivariate survival analysis demonstrated that low PNI was an independent risk factor to evaluate the prognosis of glioma patients. In lower-grade gliomas, high PNI predicted better survivals in TERT mutation only (P=0.003) and triple-negative group (P=0.007). Conclusion: In lower-grade gliomas, low PNI predicts worse survivals and PNI have differential prognostic significances in molecular groups of lower-grade gliomas.

[Clinical characteristics and microsurgical strategy of intracranial posterior circulation aneurysms]

Objective: To explore the clinical characteristics and microsurgical strategies of intracranial posterior circulation aneurysms. Methods: The clinical manifestations, imaging data, surgical approaches and follow-up results of 35 patients with circulating aneurysms (37 aneurysms) treated by microsurgery in the First Affiliated Hospital of Zhengzhou University from January 2013 to January 2018 were analyzed retrospectively. Results: A total of 22 aneurysms were clipped, 13 were clipped and resected, 1 case was clipped and together with AVM resection and 1 case was isolated. Of 37 aneurysms in 35 patients, 11 aneurysms were at the basilar artery apexes, 10 at the posterior cerebral arteries, 6 at the posterior inferior cerebellar arteries, 3 at the basilar arteries, 3 at the vertebral arteries (including 1 case of vertebral arterial dissecting aneurysm), 2 at the anterior inferior cerebellar arteries and 2 at the superior cerebellar arteries. The surgical approaches included pterional approach, extensive pterional approach, infratemporal fossa approach, retrosigmoid approach and far-lateral approach. The Glasgow Outcome Scale (GOS) scores showed good recovery in 24 cases, moderate neurological dysfunction in 6 cases, severe neurological dysfunction in 2 cases, persistent vegetative state in 1 case and 2 cases of death 6 months after their discharge from hospital. Conclusions: Posterior circulation aneurysms are adjacent to important structures. They are deep in position, with small operation space and difficult to operate. Full preoperative evaluation of the condition, selection of appropriate surgical methods are the key factors to benefit the patients.

[Effects of vitamin D3 on intestinal mucosal barrier of mice with severe burns]

Objective: To explore the effects of vitamin D₃ on intestinal mucosal barrier of mice with severe burns. Methods: Forty-two C57BL/6C male mice aged eight to twelve weeks were divided into vitamin D₃ vehicle+ sham injury group of seven mice, vitamin D₃ vehicle+ burn injury group of fourteen mice, vitamin D₃+ sham injury group of seven mice, and vitamin D₃+ burn injury group of fourteen mice according to random number table. Mice in vitamin D₃ vehicle+ sham injury group and vitamin D₃ vehicle+ burn injury group were injected with vehicle of vitamin D₃ at a dose of 0.1 mL intraperitoneally at 1, 24, and 48 h before burn experiment. Mice in vitamin D₃+ sham injury group and vitamin D₃+ burn injury group were injected with vitamin D₃ at a dose of 100 ng/kg dissolved in 0.1 mL vehicle intraperitoneally at the same time points. Mice in vitamin D₃ vehicle+ burn injury group and vitamin D₃+ burn injury group were inflicted with 30% total body surface area full-thickness dermal scald (hereinafter referred to as burn) on the back by 98 ℃ hot water for 3 to 4 seconds. And mice in vitamin D₃ vehicle+ sham injury group and vitamin D₃+ sham injury were treated with 37 ℃ water on the back for 3 to 4 seconds to simulate injury. Seven mice in vitamin D₃ vehicle+ sham injury group and seven mice in vitamin D₃+ sham injury group at post injury hour (PIH) 24, and seven mice in vitamin D₃ vehicle+ burn injury group and seven mice in vitamin D₃+ burn injury group at PIH 6 and 24 were sacrificed respectively to collect mesentery lymph nodes, spleens, livers, and intestinal tissue. The mesentery lymph nodes, spleens, and livers of mice in each group were collected to observe growth of bacteria, and number of bacteria was counted. Intestinal tissue of mice in each group was collected to detect protein expressions of zonal occludin 1 (ZO-1) and occludin by immunohistochemistry staining method, distribution of ZO-1 by immunofluorescence staining method, and expression of occludin by Western blotting. Data were processed with Kruskal-Wallis H test, Nemenyi test, one-way analysis of variance, t test, and Bonferroni correction. Results: (1) At PIH 6 and 24, bacterial counts of mesentery lymph nodes, livers, and spleens of mice in vitamin D₃ vehicle+ burn injury group were significantly higher than those of mice in vitamin D₃ vehicle+ sham injury group (P<0.05). At PIH 6, bacterial counts of livers and spleens of mice in vitamin D₃+ burn injury group were significantly lower than those of mice in vitamin D₃ vehicle+ burn injury group (P<0.05). At PIH 24, bacterial counts of mesentery lymph nodes and livers of mice in vitamin D₃+ burn injury group were significantly lower than those of mice in vitamin D₃ vehicle+ burn injury group (P<0.05). (2) At PIH 6 and 24, expressions of ZO-1 and occludin of intestinal tissue of mice in vitamin D₃ vehicle+ burn injury group were significantly lower than those of mice in vitamin D₃ vehicle+ sham injury group, and expressions of ZO-1 and occludin of intestinal tissue of mice in vitamin D₃+ burn injury group were close to those of mice in vitamin D₃+ sham injury group. At PIH 6 and 24, expressions of ZO-1 and occludin of intestinal tissue of mice in vitamin D₃+ burn injury group were significantly higher than those of mice in vitamin D₃ vehicle+ burn injury group. (3) At PIH 6 and 24, compared with that of mice in vitamin D₃ vehicle+ sham injury group, distribution of ZO-1 of intestinal mucosal epithelium of mice in vitamin D₃ vehicle+ burn injury group was discontinuous. Distribution of ZO-1 of intestinal mucosal epithelium of mice in vitamin D₃+ sham injury group was normal, and the distribution of ZO-1 of intestinal mucosal epithelium of mice in vitamin D₃+ burn injury group was with good continuity. (4) At PIH 6 and 24, expressions of occludin of intestinal tissue of mice in vitamin D₃ vehicle+ burn injury group were 0.720±0.003, 0.638±0.052 respectively, significantly lower than 0.918±0.003 of mice in vitamin D₃ vehicle+ sham injury group (t=57.33, 5.36, P<0.05). At PIH 6 and 24, expressions of occludin of intestinal tissue of mice in vitamin D₃+ burn injury group were 0.994±0.058, 1.064±0.060, close to 0.938±0.023 of mice in vitamin D₃+ sham injury group (t=0.91, 1.96, P>0.05). At PIH 6 and 24, expressions of occludin of intestinal tissue of mice in vitamin D₃ vehicle+ burn injury group were significantly lower than those of mice in vitamin D₃+ burn injury group (t=4.75, 5.35, P<0.05). Conclusions: Intestinal bacterial translocation can occur in the early stage of severe burn. And vitamin D₃ plays a protective role in the intestinal mucosal barrier post severe burn to reduce the bacterial translocation by protecting tight junction proteins of intestinal epithelium.

Synergistic O2-/Li+ Dual Ion Transportation at Atomic Scale

The ion migration during electrochemical process is a fundamental scientific issue for phase transition behavior and of technical importance for various functional devices, where cations or anions are active under electrical bias. Usually only one type of functional ion, O^2- or Li⁺, is activated due to their different migration energy barriers, cooperated by the valence change of other immobile ions in the host lattice matrix, e.g., Co²⁺/Co³⁺ and Mn³⁺/Mn⁴⁺ redox couples, owing to the charge neutralization. Here we select spinel Li₄Ti₅O₁₂ as anode and construct an all-solid-state battery under a transmission electron microscope; a synergistic transportation of O^2- and Li⁺ driven by an electrical bias was directly observed at the atomic scale. A small amount of oxygen anions was extracted firstly as a result of its lowest vacancy formation energy under 2.2 V, leading to the vertical displacement of oxygen. Up to 2.7 V, an ordered phase with both Li- and O- deficiency formed. The Li⁺ and O^2- ions are simultaneously extracted out from the [LiO₄] tetrahedra due to the electroneutrality principle. The migration paths of O and Li have been proposed and verified by first-principles calculations. These results reveal a brand new synergistic ion migration manner and may provide up-to-date insights on the transportation process of lithium ion conductors.

[Expression of dishevelled-2 in cartilage of rheumatoid arthritis and its effect on cartilage destruction]

Objective: To study the expression of dishevelled-2 (DVL2) in rheumatoid arthritis cartilage and its effect on cartilage destruction. Methods: Cartilage DVL2 expression in rat models of rheumatoid arthritis (RA), osteoarthritis(OA) and collagen-induced arthritis(CIA) were tested by Western blotting. DVL2 overexpressed lentivirus was transfected into the knee of CIA rats. Primary chondrocytes were extracted from RA patients by knee arthroplasty and transfected with DVL2 overexpressed lentivirus. Gene expression of related inflammation related cytokines was detected by real-time polymerase chain reaction (PCR) . Results: Compared with knee articular cartilage in OA patients and normal rats, DVL2 protein was highly expressed in knee cartilage of RA patients and CIA rats (P values 0.041 and 0.032, respectively). DVL2 did not significantly affect the destruction of knee cartilage in CIA rats (P=0.885). DVL2 overexpression in chondrocytes enhanced gene expression of cyclo-oxygenase-2 (COX-2), inducible nitric oxide synthase (NOS), matrix metalloproteinase (MMP) 2, MMP-3, and MMP-9, which could be more pronounced when tumor necrosis factor alpha was added. Conclusions: DVL2 is highly expressed in RA articular cartilage and promotes the expression of inflammatory cytokines and MMP gene in chondrocytes by activating Wnt/β-catenin pathway, which involves in the destruction of articular cartilage in RA.

[Mechanism of cleft palate in C57BL/6N mice induced by retinoic acid]

Objective: To investigate the mechanism of cleft palate in mice induced by excessive all-trans retinoic acid (atRA). Methods: The pregnant mice were randomly divided into atRA-treated group (n=27) and control group (n=27). atRA-treated group was given by gavage a single dose of atRA (100 mg/kg) at 8: 00 AM on gestation day 10 (GD10) and the control group was given by gavage the isopyknic corn oil. At GD13-GD15, the fetal mice palate development was observed by HE staining. The mouse embryonic palatal mesenchymal cell proliferation was detected by 5-bromo-2-deoxyuridine (BrdU) immunohistochemistry. The expressions of Smad2, phospho-Smad2 (p-Smad2), Smad4 and Smad7 in mouse embryonic palatal mesenchyme were analyzed by Western blotting. Results: At GD13-GD15, compared with the control, the ratio of BrdU-positive cells in the palatal mesenchyme of atRA-treated fetuses decreased significantly (P<0.05), especially at GD14, atRA inhibition rate was (65.4±1.7)%. Moreover, atRA decreased the levels of p-Smad2 and Smad4 in embryonic palate mesenchymal cells, whereas the expression of Smad7 was significantly increased at GD14 and GD15. Conclusions: atRA may lead to cleft palate by inhibiting the activation of Smad signaling pathway and affecting the proliferation of palatal mesenchymal cells.

[Hypoxia inducible factor-1α deSUMOylation reduces the stemness maintenance ability of endometrial cancer stem cell and increases its chemosensitivity]

Objective: To reduce the stemness maintenance ability of endometrial cancer stem cell and increase its sensitivity to chemotherapy by inducing hypoxia inducible factor 1α (HIF-1α) protein deSUMOylation. Methods: Lentiviral plasmid mediated ubiquitin carrier protein 9 (Ubc9) gene silencing was transgened into KLE endometrial carcinoma cells. The expression of Ubc9, small ubiquitin-related modifier 1(SUMO1) and HIF-1α protein was detected by Western blotting. Then tumor stem cells clones were cultured in 96 well plates, and these clone balls diameter were calculated. Cell cycles were determined by flow cytometry. MTT cytotoxicity assay and flow cytometry method were used to test sensitivity of cisplatin to endometrial cancer stem cell. Results: The results of Western blotting showed that Ubc9 gene was silenced well, and the covalent binding state of SUMO-1 and HIF-1α protein levels were significantly decreased (P<0.05). Ubc9 gene silencing in endometrial cancer cells reduced clone formation rate by (31.61±5.29)% down to (11.42±3.07)%, while the cell cycle shift from G1 to G2. IC50 of cisplatin decreased from 44.37 mg/L to 7.39 mg/L, and the rate of cell apoptosis by (41.59±5.37)% down to (26.22±4.03)%. Conclusion: The stemness maintenance ability of endometrial cancer stem cell can be reduced through deSUMOylation of HIF-1α protein by silencing Ubc9 gene expression, and their sensitivity to chemotherapy be enhanced, which provides a new reference for future gene therapy of endometrial carcinoma.

[Efficacy and safety of transbronchial cryobiopsy in the etiologic diagnosis of diffuse lung disease]

Objective: To assess the efficacy and safety of transbronchial cryobiopsy (TBCB) for the etiologic evaluation of diffuse lung disease (DLD). Methods: Between December 2015 to April 2017, a total of 38 patients with DLD met the inclusion criteria for TBCB in the First Affiliated Hospital of Chongqing Medical University, and 35 of them consented to undergo the procedure under rigid or flexible bronchoscopy. On the tissues obtained from the 35 patients, histopathologic and microbiological evaluations were performed, and together with clinical and radiological manifestations, diagnoses were made and the efficacy of TBCB in the diagnosis of DLD was confirmed, and then therapies were planned accordingly. Complications of the biopsy procedures were recorded. Results: Of the 35 patients who were enrolled, 24 underwent TBCB under rigid bronchoscopy and 11 under flexible bronchoscopy. Another 3 patients refused the procedure due to disinclination to invasive examinations. One single procedure of TBCB took (51.8±19.2) min on average, the median number of tissues obtained was 6 (5, 8), and the median area of tissues was 15 (9, 20) mm(2).Definite diagnoses were reached in 33 patients, including idiopathic nonspecific interstitial pneumonia (n=8), connective tissue disease-interstitial lung disease (n=8), occupational lung disease (n=4), idiopathic pulmonary fibrosis (n=3), interstitial pneumonia with autoimmune features (n=3), tuberculosis (n=2), cryptogenic organization pneumonia (n=1), acute interstitial pneumonia (n=1), pulmonary infection (n=1), hypersensitivity pneumonia (n=1) and sarcoidosis (n=1). Diagnostic yield was 94.3% (33 out of 35 cases diagnosed). Pneumothorax occurred in 3 patients (1 patients with mild pneumothorax , 1 moderate and 1 severe), and were resolved with thoracic puncture or pleural drainage. Bleeding occurred in all 24 patients who received TBCB under rigid bronchoscopy (11 patients with mild bleeding, 12 moderate and 1 severe) and was controlled after coagulation measures. After one month of treatment according to the diagnoses acquired with cryobiopsy, the condition was cured in 1 patient (3.0%), alleviated in 17 (51.5%), stable in 11 (33.3%), and deteriorated in 4 (12.1%). Conclusion: TBCB yields reliable diagnoses with a good safety profile.

[Interaction between polycyclic aromatic hydrocarbons and high risk human papillomavirus infection on cervical intraepithelial neoplasia]

Objective: To evaluate the effects of polycyclic aromatic hydrocarbons (PAHs) and high risk human papillomavirus (HR-HPV) infection and their interaction on the progression of cervical intraepithelial neoplasia. Methods: A total of 486 patients, including 208 women with normal cervix (NC), 154 patients with low-grade cervical intraepithelial neoplasm (CINⅠ), 124 patients with high-grade cervical intraepithelial neoplasm (CINⅡ/Ⅲ), were selected from the cervical lesions cohort from June to December, 2014. HR-HPV was detected by using flow-through hybridization technology and the urine concentration of 1-hydroxypyrene (1-OHP) was detected with high performance liquid chromatography. By using software SPSS 22.0, the χ(2) test, trend χ(2) test, Kruskal-Wallis H test, Nemenyi rank test and Spearman rank correlation analysis were performed. And the interaction effects were evaluated by additive model. Results: The HR-HPV infection rates in NC, CINⅠ and CINⅡ/Ⅲ groups were 27.9%, 37.0% and 58.9%, respectively. The urine concentrations of 1-OHP (μmol/molCr) were 0.07±0.09, 0.11±0.10 and 0.17±0.15, respectively. With increasing severity of the cervical lesions, the HR-HPV infection rate gradually increased (trend χ(2)=29.89, P<0.001) and the high exposure rate of PAHs gradually increased (trend χ(2)=27.94, P<0.001). HR-HPV infection was positively correlated with 1-OHP exposure (r=0.680, P<0.001). There was a positive additive interaction between HPV infection and PAHs exposure in CIN Ⅱ/Ⅲ group, but it was not found in CIN Ⅰ group. Conclusion: Both HR-HPV infection and high exposure of PAHs might increase the risk of cervical intraepithelial neoplasm, and might have a synergistic effect on the progression of high-grade cervical intraepithelial neoplasia.

[Effect of Dishevelled 2 on apoptosis in rheumatoid arthritis fibroblast-like synoviocytes through inhibiting JAK-STAT pathway]

Objective: To investigate if Dishevelled 2 (DVL2) regulates the apoptosis of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS) via the JAK-STAT pathway. Methods: DVL2 overexpressed lentivirus was transfected into RA-FLS and the apoptosis rate was detected by flow cytometry. The effect of DVL2 on RA-FLS signaling pathway was detected by RNA-seq, and then the key genes were verified by RT-PCR. Results: Compared with the control group, DVL2 significantly increased the apoptosis rate of MH7A (3.2%±2.2% vs 25.7%±4.5%). RNA-seq results showed that DVL2 down-regulated the JAK-STAT pathway.The results of RT-PCR showed that DVL2 inhibited the gene expression of JAK2, Stat1, and Stat2; DVL2 still inhibited the gene expression of JAK2 and Stat2 but not Stat1 after TNF-α stimulation.DVL2 inhibited the gene expression of Bcl-xL, and the gene expression of Bcl-2 and Bcl-xL after TNF-α stimulation. Conclusion: DVL2 can increase the apoptosis rate of RA-FLS through inhibiting the JAK-STAT pathway and its downstream anti-apoptotic gene.

[DeSUMOylation of protein kinase B1 inhibits cell proliferation and metastasis of hepatocellular carcinoma]

Objective: To investigate the effect of AKT1 deSUMOylation induced by Ubc9 silencing on the proliferation and metastasis of hepatocellular carcinoma (HCC) cells. Methods: The Ubc9 gene was silenced using RNA interference, and the expression levels of Ubc9, SUMO1 and AKT1 protein were detected by Western blot. Cell proliferation and cell cycle was analyzed by MTT and flow cytometry. Wound healing and transwell assays were used to detect the cell migration ability. Furthermore, the xenograft model was established, and tumor growth curves were drawn. The in situ apoptotic rates was measured using TUNEL Apoptosis Assay. The expression of proliferating cell nuclear antigen (PCNA), matrix metalloproteinase (MMP)-2 and MMP-9 were evaluated by immunohistochemical staining. Results: Knockdown of Ubc9 gene significantly decreased the protein expression levels of Ubc9, conjugated SUMO1, free SUMO1 and AKT1 in HCC cells (P<0.05 for all). In control, siR-neg and siR-Ubc9 groups, the cell proliferation indexes were 53.19%, 54.25% and 39.17%, respectively. Moreover, cell migration distance and migrating cells per low power field for all these three groups were (59.47±4.66) μm and 89.44±8.36, (56.56±5.37) μm and 93.84±8.79, as well as (34.57±6.61) μm and 41.67±5.39, respectively. In the xenograft model, the weights of subcutaneous tumors for these three groups were (3.78±0.69) g, (3.72±0.72) g and (2.09±0.61) g, respectively. The corresponding apoptotic cell rates were (7.79±2.21)%, (6.45±2.48)% and (33.59±5.44)%, respectively. The expression levels of PCNA, MMP-2 and MMP-9 protein were significantly decreased in siR-Ubc9 group (P<0.05). Conclusions: Ubc9 silencing in HCC cells induces AKT1 deSUMOylation, and then inhibits the proliferation and metastasis. These results provide a new therapeutic strategy for liver cancer in the future.

[Analysis of prevalence and related factors of osteoporosis in retired population based on Dongfeng-Tongji Cohort]

Objective: To investigate the prevalence and related factors of osteoporosis among retired population in Dongfeng-Tongji cohort. Methods: 27 009 retired participants were recruited from Dongfeng Motor Corporation in Hubei Province in 2008 and followed up from April to October in 2013. newly retired participants also were recruited. Data were collected by using questionnaire, physical examination, serum hepatase detection and bone densitometry. Totally, 30 916 participants were included for data analysis after excluding participants with severe bone metabolic diseases, taking hormone drugs, incomplete follow-up data and who were under 45 years old. Age-standardized prevalence of osteoporosis was calculated according to data of the 2010 Sixth National Population Census. Multivariate logistic regression analysis was applied to explore the associated factors of osteoporosis. Results: Prevalence of osteoporosis was 42.3% (13 083/30 916) and age standardized prevalence was 40.7%: 35.0% (4 854/13 878) and 34.8% for males; 48.3% (8 229/17 038) and 47.1% for females. Significantly associated factors with osteoporosis for both males and females included: older age (male: OR=1.67, 95%CI: 1.40-1.99; female:OR=3.34, 95%CI: 2.70-4.13), lower BMI (male: OR=1.70, 95%CI: 1.40-2.06; female: OR=1.27, 95%CI: 1.04-1.53), exercise (male: OR=0.69, 95%CI: 0.61-0.78; female: OR=0.87, 95%CI: 0.80-0.96), abnormal elevated serum alkaline phosphatase (ALP) (male: OR=1.12, 95%CI: 1.01-1.24; female: OR=1.15, 95%CI: 1.06-1.25), γ-glutamyltransferase (γ-GT) (male: OR=1.16, 95%CI: 1.02-1.30; female: OR=1.13, 95%CI: 1.03-1.24) and aspartate transaminase/alanine aminotransferase (AST/ALT) (male: OR=1.15, 95%CI: 1.05-1.25; female: OR=1.28, 95%CI: 1.19-1.38). Smoking (OR=1.27, 95%CI: 1.07-1.39) and drinking (OR=1.11, 95%CI: 1.08-1.16) were associated factors for males while menopausal (OR=1.67, 95%CI: 1.47-1.89) for females. There were positive dose-response correlation relationships of serum levels of ALP, γ-GT and AST/ALT with osteoporosis (all P values<0.05). Conclusion: Osteoporosis was relatively common among retired population in Dongfeng-Tongji cohort. In addition to known factors such as older age, lower BMI and exercise, abnormal elevated serum ALP, γ-GT and AST/ALT were also associated with osteoporosis.

Facilitation of ultrasonic microvesicles on homing and molecular mechanism of bone marrow mesenchymal stem cells in cerebral infarction patients

OBJECTIVE

Cerebral infarction, or ischemia brain stroke, is a common cerebrovascular disease. Bone marrow mesenchymal stem cells (BMSCs) are widely used to treating ischemia disease such as cardiac infarction. Ultrasonic microvesicles may help the targeting of exogenous factors via localized energy blast. Therefore, this study aims to investigate the effect of ultrasonic microvesicles on the homing of BMSCs on artery thrombosis and the associated molecular mechanisms.

MATERIALS AND METHODS

Rat BMSCs were isolated and cultured. Rats were divided into sham, model, BMSCs, and microvesicles groups. Cerebral infarction model was prepared by ligation of cervical artery and middle cerebral artery. 3×106/kg BMSCs were transplanted via tail veins. Microvesicles were used for assisting BMSCs infusion. Sex-determining region Y (SRY) gene expression was measured by Real-time PCR, while 2,3,5-triphenyltetrazolium chloride (TTC) staining was employed for describing the area of cerebral infarction. The activity of caspase 3 was assayed by test kit. Vascular endothelial growth factor (VEGF), nuclear factor kappa B (NF-κB) mRNA/protein levels, were quantified by Real-time PCR, and Western blotting, respectively.

RESULTS

Microvesicle group had significantly elevated SRY expression (p<0.05 compared to BMSCs group). Transplantation of BMSCs remarkably decreased cerebral infarction area, caspase 3 activity or NF-κB expression, and increased VEGF expression (p<0.05 compared to model group). Microvesicle induced BMSCs had more potent effects (p<0.01).

CONCLUSIONS

Ultrasound microvesicle facilitated homing of BMSCs in cerebral infarction, and improved infarction disease via up-regulating VEGF expression, inhibiting NF-κB expression, and modulating apoptosis.

[The bisphenol A-enhanced activity of thyroid carcinoma cell line B-CPAP is inhibited by Icarrin]

Objective: To investigate the effect of icariin (ICA) on the bisphenol A (BPA)-enhanced proliferation function of thyroid carcinoma cell B-CPAP and underlying mechanism. Methods: The proliferation of Gastric B-CPAP cell line was evaluated by cell counting kit-8 (CCK-8). Apoptosis and ROS expression in B-CPAP cells were detected by flow cytometry. The expression of superoxide dismutase (SOD) and malondialdehyde (MDA) in B-CPAP cells were measured by individual assay kits. The expressions of Bcl-2 and γ-HA2X were detected by Western blot. SPSS 18.0 software was used to analyze the data. Results: B-CPAP cell activity was promoted by treatment with 3×10(-7)mol/L BPA for 48 h, with significant difference in absorbance between BPA and control groups (1.089±0.053 vs 0.935±0.010, P<0.05). The cell activities of BPA+ ICA(25), BPA+ ICA(50), BPA+ ICA(100) and BPA+ ICA(200) groups was 0.780±0.036, 1.007±0.050, 0.958±0.033 and 0.625±0.064, respectively (all P<0.01). The proliferation of B-CPAP cells treated with BPA for 72 hours showed a similar trend to 48 hours. There was no significant difference between all treatment groups in 24 hours. The apoptosis rate was (19.272±0.186)% in BPA-treated cells, and was (22.412±0.238)% in control cells (P<0.05). The apoptosis rates of BPA+ ICA(50) and BPA+ ICA(200) groups were (23.688±0.412)% and (30.270±0.696)%, respectively (P<0.01). The intracellular accumulation of ROS in BPA, BPA+ ICA(50), and BPA+ ICA(200) groups were 806±21, 1 772±37, 2 041±16, respectively (P<0.01). The expressions of anti-apoptotic protein Bcl-2 in control, BPA, BPA+ ICA(50), BPA+ ICA(200) groups were 7 120±151, 9 801±286, 5 902±171 and 4 203±216, respectively (P<0.01). Conclusion: BPA can promote the proliferation of thyroid carcinoma B-CPAP cells and decrease the apoptosis of cells, and this effect can be inhibited by ICA. The possible mechanism is to induce high expression of intracellular ROS and inhibit the expression of antioxidase system, leading to cell oxidative damage, thereby inducing apoptosis.

[Interaction between polycyclic aromatic hydrocarbons and p16, FHIT gene CpG island methylation in patients with cervical intraepithelial neoplasias]

Objective: To explore the effect of polycyclic aromatic hydrocarbons (PAHs) and p16, FHIT gene CpG island methylation, as well as their interaction in cervical intraepithelial neoplasias. Methods: Objects of this study were from a cohort of cervical lesions study in Yangqu county of Shanxi province. All the patients were diagnosed pathologically, that including 83 patients with high-grade cervical intraepithelial neoplasia (CINⅡ/Ⅲ), 86 patients with low-grade cervical intraepithelial neoplasia (CINⅠ) and another 91 women under normal cervical (NC) condition. 1-hydroxy pyrene in the urine was detected by high performance liquid chromatography (HPLC) while CpG island methylation status of tumor suppressor gene p16 and FHIT were measured by methylation-specifc polymerase chain reaction (MSP). Data were analyzed with Kruskal-Wallis H test, chi-square test and trend of chi-square test. Logistic regression models were used to estimate the odds ratio (OR) and corresponding 95% confidence intervals (95%CI) between influencing factors and the cervical disease by using the SPSS statistical software (version 20.0). The interaction under study was evaluated by using the generalized multifactor dimensionality reduction (GMDR) model. Results: Level of 1-hydroxy pyrene (H=50.743, P<0.001) and the high exposure rate of 1-hydroxy pyrene (trend χ(2)=20.146, P<0.001) were gradually increasing along with the severity of cervical intraepithelial neoplasia. The CpG island methylation rates of p16, FHIT in CINⅠand CINⅡ/Ⅲ group were higher than that in NC group, and gradually increasing along with the severity of cervical intraepithelial neoplasia (trend χ(2)=9.75, P=0.002; trend χ(2)=10.39, P=0.001). Results from the GMDR model showed that interaction existed among the high exposure of 1-hydroxy pyrene and the CpG island methylation of p16, FHIT in CINⅠ and CINⅡ/Ⅲ group. Conclusion: Under the high exposure of 1-hydroxy pyrene and the CpG island methylation of p16, FHIT appeared to have increased the risk of cervical intraepithelial neoplasia and causing synergistic effect in cervical intraepithelial neoplasia.

Enhancing expression of SSU1 genes in Saccharomyces uvarum leads to an increase in sulfite tolerance and a transcriptome profile change

Saccharomyces uvarum is a good wine yeast species that may have great potential for the future. However, sulfur tolerance of most S. uvarum strains is very poor. In addition there is still little information about the SSU1 gene of S. uvarum, which encodes a putative transporter conferring sulfite tolerance. In order to analyze the function of the SSU1 gene, two expression vectors that contained different SSU1 genes were constructed and transferred into a sulfite-tolerant S. uvarum strain, A9. Then sulfite tolerance, SO2 production, and PCR, sequencing, RT-qPCR and transcriptome analyses were used to access the function of the S. uvarum SSU1 gene. Our results illustrated that enhancing expression of the SSU1 gene can promote sulfite resistance in S. uvarum, and an insertion fragment ahead of the additional SSU1 gene, as seen in some alleles, could affect the expression of other genes and the sulfite tolerance level of S. uvarum. This is the first report on enhancing the expression of the SSU1 gene of S. uvarum.

Efficacy of a combination of taurine and stenosis removing on cognitive impairment induced by carotid artery stenosis in rats

OBJECTIVE

We assessed the protective effect on a carotid artery stenosis rat model with using a combination of taurine and stenosis treatment. Rats were randomly divided into five groups: Group 1 (sham), Group 2 (model), Group 3 (stenosis removing), Group 4 (taurine), and Group 5 (combination).

MATERIALS AND METHODS

The carotid artery stenosis model was created by ligating the common carotid artery along with various gauges of needle and then removing the needle. The cognitive performance was analyzed using P300 latency and escape latency in the Morris water maze (MWM) task. The levels of oxidative products malondialdehyde (MDA), inflammatory factors interleukin (IL-1β) and tumor necrosis factor (TNF-α), the activities of anti-oxidative enzymes superoxide dismutase (SOD) and catalase (CAT) were determined using enzyme-linked immunosorbent assay (ELISA) kits, respectively.

RESULTS

The results revealed that the cognitive impairment can be reduced by stenosis removing and taurine, combining the administration of stenosis removing and taurine had a significant effect on the recovery of cognitive function.

CONCLUSIONS

A further study showed that, the protection of cognitive function is related to inhibition of oxidative stress and suppression of inflammatory response.

Liguisticum wallichii inhibits renal carcinoma progression by downregulating UBE3A and through suppression of NF-κB signaling

Renal carcinoma accounts for a fifth of the morbidity among malignant tumors in China. Ubiquitin-protein ligase E3A (UBE3A) plays an important role in the occurrence and development of gene mutation-induced diseases. This study was designed to investigate the mechanism of Liguistium wallichii in treating renal carcinoma. Hematoxylin and eosin staining was applied to detect the pathological changes in a rat renal carcinoma model. The experimental group received L. wallichii treatment at 100 mg/kg every 48 h for 4 weeks, while the control group only received normal saline. The proliferation index Ki67 was measured by immunohistochemistry. Primary renal carcinoma cells were isolated and UBE3A expression was measured by quantitative polymerase chain reaction. The related signaling pathway was screened by the Pathway Finder Array. pP65 nuclear import was detected by immunofluorescence. A total of 60 rats were used for the renal carcinoma model, of which 58 rats were successfully established and equally divided into two groups: L. wallichii and normal saline. Ki67 expression decreased in the L. wallichii group and was upregulated in the normal saline group. Histological analysis showed significant renal cell nucleus division in the normal saline group. The UBE3A level decreased after L. wallichii treatment compared to the level in the normal saline group. The Pathway Finder Array revealed that the NF-κB signaling pathway was activated, and pP65 presented obvious nuclear import in the normal saline group. In conclusion, L. wallichii inhibits renal carcinoma progression by downregulating UBE3A and suppressing the NF-κB signaling pathway.

Note: Application of a novel 2(3HUS+S) parallel manipulator for simulation of hip joint motion

In the paper, a novel 2(3HUS+S) parallel manipulator, which has two moving platforms, is proposed. The parallel manipulator is adopted to simulate hip joint motion and can conduct an experiment for two hip joints simultaneously. Motion experiments are conducted in the paper, and the recommended hip joint motion curves from ISO14242 and actual hip joint motions during jogging and walking are selected as the simulated motions. The experimental results indicate that the 2(3HUS+S) parallel manipulator can realize the simulation of many kinds of hip joint motions without changing the structure size.