The accuracy and repeatability of computer aided cervical vertebra landmarking (CACVL) were investigated in cephalogram. 120 adolescents (60 boys, 60 girls) aged from 9.1 to 17.2 years old were randomly selected. Twenty-seven landmarks from the second to fifth cervical vertebrae on the lateral cephalogram were identified. In this study, the system of CACVL was developed and used to identify and calculate the landmarks by fast marching method and parabolic curve fitting. The accuracy and repeatability in CACVL group were compared with those in two manual landmarking groups [orthodontic experts (OE) group and orthodontic novices (ON) group]. The results showed that, as for the accuracy, there was no significant difference between CACVL group and OE group no matter in x-axis or y-axis (P>0.05), but there was significant difference between CACVL group and ON group, as well as OE group and ON group in both axes (P<0.05). As for the repeatability, CACVL group was more reliable than OE group and ON group in both axes. It is concluded that CACVL has the same or higher accuracy, better repeatability and less workload than manual landmarking methods. It's reliable for cervical parameters identification on the lateral cephalogram and cervical vertebral maturation prediction in orthodontic practice and research.

Objective To evaluate the methods and efficacy of microsurgical treatment for the premalignant and malignant lesions of the conjunctiva. Methods Forty-seven patients witn premalignant and malignant lesions of the conjuncitva were managed by microsurgical, these patients include 12 melanoma, 26 squamous cell carcinoma, 6 Bowen’ diseases, 3 primary acquired melanosis. The surgical method differs with limbal tumors, extralimbal tumors, and primary acquired melanosis. Results In all 47 patients, the tumor was completely removed in in one procedure. After follow-up for 4~60 months(mean 17 months), these were no tumor recurrence. Conclusion It is effective methods that premalignant and malignant lesions of the conjunctiva are managed by microsurgical resection, alcohol application, and supplemental cryotherapy. Careful propeirativa clinical evaluation of patient with a conjunctiva neoplasm is important in making the correct diagnosis and planning the surgical approach.

Objective To sequence and analyze the envelope (E) gene of type Ⅰ dengue virus isolated from Guangzhou in 2009 for tracing the infection source. Methods The serum samples were collected from patients diagnosed with dengue fever in Guangzhou area during 2009. Dengue virus was isolated and cultured in C6/36 cells.The whole length of E gene was amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) and then sequenced. The phylogenetic tree was drawn by neighbor-joining method. The bioinformatics analysis was performed by combining the phylogenetic information and the epidemiology data. Results Four strains of type Ⅰ dengue virus were isolated from 19 samples. E gene of these strains was amplified and sequenced. The phylogenetic analysis showed that 09/GZ/9104 strain and 09/GZ/9236 strain had identical nucleotide sequence and fell within the American/African group, 09/GZ/11534 stain and 09/GZ/11562 strain had similar sequence homology and fell within the Asian group. Conclusion The typeⅠdengue viruses in Guangzhou area in 2009 are imported, which belong to two genotypes and may come from two independent origins respectively.

AIM:Toinvestigatetheeffectofnicotinicacidamide(NAA)ontheinfusiondamageofhuman umbilical cord mesenchymal stem cells ( hUC-MSCs) under the condition of instant blood-mediated inflammatory reaction ( IBMIR) .METHODS:Normal peripheral blood without anticoagulant at volume of 2.7 mL was mixed with 0.3 mL phys-iological saline (as blank group), CFSE labeled hUC-MSCs (1 ×106 cells in 0.3 mL as MSC group) and CFSE labeled hUC-MSCs (1 ×106 cells in 0.3 mL) preprocessed with NAA at concentration of 10 mmol/L for 24 h ( as MSC+NAA group) , respectively.The mixture was immediately injected into the improved Chandler Loop model, placed in 37℃water bath, and then started the peristaltic pump at the speed of 20 mL/min for 1 h.The number of CFSE labeled hUC-MSCs, platelets, white blood cells were counted and the concentration of complement C3a was measured before and after cycling, respectively.RESULTS: After 1 h circulation, the platelet dissipation rate were ( 29.96 ±10.88 )% in blank group, (77.76 ±19.29)% in MSC group all and (50.13 ±18.10)% in MSC +NAA group; and the leukocyte counts were (37.82 ±13.81)%in blank group, (64.57 ±17.08)% in MSC group and (41.52 ±17.26)% in MSC+NAA group. Compared with blank group, the differences of the dissipation rates in MSC group and MSC+NAA group all had statistical significance.The hUC-MSCs relative survival rate in MSC+NAA group was higher than that in MSC group.C3a concentra-tions in blank group, MSC group and MSC+NAA group were (206.27 ±58.10), (230.47 ±39.61) and (208.37 ± 40.66) μg/L, respectively.CONCLUSION:Co-circulating the mixture of hUC-MSCs with normal peripheral blood with-out anticoagulant in the improved Chandler Loop for 1 h depletes a large number of hUC-MSCs and blood components, and increases C3a, suggesting that this model can induce IBMIR.NAA has a protective effect on the hUC-MSCs in the infusion damage by inhibiting IBMIR, reducing the wastage of the blood components and enhancing the survival rate of the hUC-MSCs.

Objective To investigate the changes of the immunological factors in subcutaneous exudate and blood components of the rats receiving cutaneous scraping method,and to compare the changes of skin histopathological features before and after cutaneous scraping under microscope.Methods SD rats were randomly divided into two groups,cutaneous-scraping group and non-cutaneous-scraping group.And then each group was divided into three subgroups.The observation indexes included the levels of interleukin (IL)-1β,IL-6 and interferon gamma (IFN-γ) in the blood and the skin,routine blood examination,and skin histopathological features.Results In cutaneous-scraping group,the number of white blood cells in the blood and the levels of IL-1 β and IFN-γ in skin tissues were increased (P ＜ 0.05),the hemolysis rate was increased (P ＜ 0.05).However,the levels of IL-1β,IL-6 and IFN-γin the blood showed no obvious changes.Under the microscope,severe skin edema,vascular congestion and dilatation,and infiltration of inflammatory cells were found in the skin after cutaneous scraping.Conclusion The cutaneous scraping method can activate the immune response rapidly,and the immunological components of the subcutaneous exudate after cutaneous scraping are helpful to the disease treatment.

AIM:To investigate the influence of continuous subculturing of human umbilical cord mesenchymal stem cells (hUC-MSCs) on the mRNA expression of all 23 family members of NOD-like receptors (NLRs), and to search for the way of improving the subculture quality of hUC-MSCs and increasing the quantity and safety in the experimental and clinical application .METHODS:Neonatal umbilical cord was collected to isolate and purify the hUC-MSCs with the colla-genase II digestion and adherence screening methods .These cells were continuously subcultured .The hUC-MSCs at pas-sage 3 and passage 28 were identified by flow cytometry and induced differentiation .The mRNA expression of NLRs in the passage 3 and passage 28 hUC-MSCs was detected by RT-qPCR.RESULTS: The cell phenotypes of both passage 3 and passage 28 hUC-MSCs were CD29 +/CD44 +/CD105 +/CD31 -/CD34 -/CD40 -/CD45 -/CD106 -/HLA-DR-, and both of the cells were induced into osteoblasts and adipocytes , which were conformed to the criteria of International Society for Cellular Therapy to define MSCs .All the NLR family members were expressed in passage 3 hUC-MSCs.NOD1, NLRC4, NLRC5, NLRP1, NLRP3, NLRP10, NAIP, NLRX1 and APAF1 at mRNA levels were highly expressed , and the rest were lowly expressed.When hUC-MSCs were subcultured to passage 28, NLRP10 mRNA was increased, NLRC5 mRNA and NLRX1 mRNA were hardly changed , and all of the rest members were decreased .The difference of NLRP1 mRNA expres-sion between passage 3 and passage 28 hUC-MSCs was observed with statistical significance (P<0.05).CONCLU-SION:The effects of subculturing on the expression of NLR family in hUC-MSCs are pleiotropic .It requires further investi-gation to confirm whether these effects are related to the proliferation , differentiation and immunomodulation of MSCs .

The accuracy and repeatability of computer aided cervical vertebra landmarking (CACVL) were investigated in cephalogram.120 adolescents (60 boys,60 girls) aged from 9.1 to 17.2 years old were randomly selected.Twenty-seven landmarks from the second to fifth cervical vertebrae on the lateral cephalogram.were identified.In this study,the system of CACVL was developed and used to identify and calculate the landmarks by fast marching method and parabolic curve fitting.The accuracy and repeatability in CACVL group were compared with those in two manual landmarking groups [orthodontic experts (OE) group and orthodontic novices (ON) group].The results showed that,as for the accu racy,there was no significant difference between CACVL group and OE group no matter in x-axis or y-axis (P＞0.05),but there was significant difference between CACVL group and ON group,as well as OE group and ON group in both axes (P＜0.05).As for the repeatability,CACVL group was more reliable than OE group and ON group in both axes.It is concluded that CACVL has the same or higher accuracy,better repeatability and less workload than manual landmarking methods.It's reliable for cervical parameters identification on the lateral cephalogram and cervical vertebral maturation prediction in orthodontic practice and research.

Objective:To investigate the learning curve of laparoscopic transanal total mesorectal excision (taTME) for rectal cancer operated by one or two surgery teams.Methods:The retrospective cross-sectional study was conducted. Based on the concept of real-world research, the clinical data of 1 458 patients undergoing laparoscopic rectal cancer taTME from 44 medical centers who were registered in the Chinese taTME registry collaborative (CTRC) database from May 2010 to May 2020 were collected. The 1 458 patients were divided into cohorts with one surgery team or two surgery teams according to the operation method. Patients with one surgery team underwent taTME by transabdominal operation and then by transanal operation. Patients with two surgery teams underwent taTME by transabdominal and transanal operation simultaneously with duration of the simutaneous operation time ≥30 minutes. The entire surgical process of patients with two surgery teams is not required to be performed by two surgery teams simutaneously. The clinical data were collected from the medical centers with similar operation amount according to the operation time sequence to analyze the difference between different operation stages and explore the learning curve. The operation time was taken as the parameter to carry out cumulative sum analysis and draw the learning curve of laparoscopic rectal cancer taTME in each medical center. The clinicopathological characteristics of patients from two medical centers with the largest difference in learning curves were analyzed. Observation indicators: (1) screening results of clinical data; (2) clinical data collection of patients with one surgery team; (3) surgical situations of laparoscopic rectal cancer taTME from the one surgery team in different operation stages; (4) learning curve of the one surgery team; (5) clinical data collection of patients with two surgery teams; (6) surgical situations of laparoscopic rectal cancer taTME from the two surgery teams; (7) learning curve of the two surgery teams. The cumulative sum was calculated by the CUSUM=∑i=1nXi-U, where Xi represented the operation time of each taTME, U represented the average operation time of all cases, and n represented the operation number. Fitting process was conducted on scatter plot of learning curves. Taking the apex of learning curve as the boundary, the learning curve was divided into two stages. The abscissa corresponding to the apex of learning curve was the number of operations that needed to be performed to cross the learning curve. Measurement data with normal distribution were represented as Mean±SD. Comparison between two groups was conducted using the t test and comparison between multiple groups was conducted using the ANOVA. Measurement data with skewed distribution were represented as M( P25,P75), and comparison between groups was conducted using the Mann-Whitney U test. Comparison of ordinal data was analyzed using the rank sum test. Count data were analyzed using the chi-square test or Fisher exact probability. Results:(1) Screening results of clinical data:the clinical data of 661 patients from 7 medical centers with one surgery team and two surgery teams were collected. (2) Clinical data collection of patients with one surgery team: the clinical data of 312 patients undergoing laparoscopic rectal cancer taTME from 5 medical centers were collected including 42 cases in the number 2 medical center, 97 cases in the number 20 medical center, 82 cases in the number 33 medical center, 35 cases in the number 37 medical center and 56 cases in the number 39 medical center, respectively. (3) Surgical situations of laparoscopic rectal cancer taTME from the one surgery team in different operation stages: three medical centers including the number 2, number 37 and number 39 medical center with close operation volume provided the clinical data of cases distributed in five operation stages. Among the five operation stages, the proportion of high-quality operation of total mesorectal excision (TME) was ≥17/18, the incidence of postoperative complications was ≤13.3%(4/30) and the incidence of anastomotic leakage was ≤10.0%(3/30). There was no significant difference in the TME quality, postoperative complications or anastomotic leakage among the five operation stages ( P>0.05). There was no significant difference in the operation time among the five operation stages ( χ2=6.950, P>0.05). (4) Learning curve of the one surgery team: the number of operations corresponding to the turning point of learning curve in number 2 and number 20 medical center was 22 and 39, respectively. The number of operations corresponding to the turning points of learning curve in number 33 and number 37 medical center was 15, 66 and 10, 28, respectively. The number of operations corresponding to the turning point of learning curve in number 39 medical center was 20. The overall curve of number 20 medical center was in line with the trend of learning curve and 39 cases of operations was the minimum number needed to cross the learning curve. The biggest difference in learning curve was shown between the number 20 and number 33 medical center. Cases with the gender of male or female, age, body mass index, cases classified as stage 1, stage 2, stage 3 or stage 4 of the American Society of Anesthesiologists (ASA) Classification, cases with neoadjuvant therapy, duration of postoperative hospital stay of the number 20 medical center were 77, 20, (60±10)years, 24 kg/m 2(22 kg/m 2, 26 kg/m 2), 1, 88, 8, 0, 8, 8, 11 days (9 days, 13 days), respectively, versus 51, 31, (64±11)years, 23 kg/m 2(21 kg/m 2, 26 kg/m 2), 0, 35, 43, 1, 31, 16 days (13 day, 21 day) of number 33 medical center, showing significant differences in the above indicators between the two medical centers ( χ2 =6.442, t=-2.265, Z=-2.032, -6.870, χ2 =22.120, Z=-8.408, P<0.05). (5) Clinical data collection of the two surgery teams: the clinical data of 259 patients undergoing laparoscopic rectal cancer taTME from 5 medical centers were collected, including 46 cases in the number 2 medical center, 47 cases in the number 8 medical center, 78 cases in the number 18 medical center, 43 cases in the number 33 medical center and 45 cases in the number 44 medical center, respectively. (6) Surgical situations of laparoscopic rectal cancer taTME from the two surgery teams: four medical centers including the number 2, number 8, number 33 and number 44 medical center with close operation volume provided the clinical data of cases distributed in four operation stages. Among the four operation stages, the proportion of high-quality operation of TME was ≥50.0%(13/26), the incidence of postoperative complications was ≤35.0%(14/40) and the incidence of anastomotic leakage was ≤22.5%(9/40). There was no significant difference in the TME quality, postoperative complications or operation time among the four operation stages ( χ2 =3.252, 4.733, 8.848, P>0.05). There was a significant difference in the incidence of anastomotic leakage among the four operation stages ( P<0.05). (7) Learning curve of the two surgery teams: the number of operations corresponding to the turning point of learning curve in number 2 and number 8 medical center was 28 and 16, respectively. The number of operations corresponding to the turning points of learning curve in number 18, number 33 and number 44 medical center was 12 and 58, 10 and 36, 14 and 36, respectively. The overall curve of number 2 medical center was in line with the trend of learning curve and 28 cases of operations was the minimum number needed to cross the learning curve. The biggest difference in learning curve was shown between the number 2 and number 33 medical center. The age and cases with tumor in stage T0 and (or) Tis, stage T1, stage T2, stage T3 or stage T4 of the T staging of the number 2 and number 33 medical center were (60±12)years, 3, 1, 9, 11, 20 and (65±10)years, 2, 3, 22, 15, 0, respectively, showing significant differences in the above indicators between the two medical centers ( t=-2.280, Z=-4.033, P<0.05). Conclusion:Thirty-nine cases of operations was the minimum number for the one surgery team to cross the learning curve of laparoscopic rectal cancer taTME and 28 cases of operations was the minimum number for the two surgery teams to cross the learning curve of laparoscopic rectal cancer taTME.

Objective: To evaluate the measured value of gadoxetic disodium - enhanced T1-weighted magnetic resonance for the prediction of liver damage (LD) including liver fibrosis and inflammation. Methods: Retrospectively analyzed laboratory data of 115 patients with pathological results including prothrombin time (PT), albumin, serum total bilirubin level (TBil), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and magnetic resonance measurements (T1 measurement before and after enhancement and hepatobiliary specific phase T1pre, T1post, and changes in T1 relaxation time before and after enhancement were measured). The correlation between LD and magnetic resonance measurements was assessed by Spearman’s correlation. All cases were divided into two groups: LD < 1 and LD≥1 (n1 = 26, n2 = 89), and the mean value of both groups was compared by t-test or Mann-Whitney U test. The independent influence factors of LD were obtained by binary logistic regression model. The area under receiver operating characteristics (AUROC) curve was performed on T1pre, T1post, and variation values. Results: Spearman's correlation test showed that T1post and variation values ​​were significantly associated with LD, and the correlation coefficients were 0.435, -0.353 and P < 0.05, respectively. The mean values ​​of T1post, variation values, PT, albumin, ALT and AST were statistically significant (P < 0.05). Binary logistic regression model showed T1post (P = 0.006), PT (P = 0.003), and AST (P = 0.032) were independent influencing factors of LD. T1- post contrast was good predictor of liver damage (AUC = 0.800). Conclusion T1-post contrast predicts the existence of liver damage and provides useful information for clinical diagnosis and treatment.

Objective To examine the incidence ,clinical characteristics ,and risk factors for falls within two years after stroke in elderly patients. Methods A total of 365 elderly stroke patients from the Department of Neurology at the 8th Nanning People's Hospital were recruited from June 1 , 2013 to December 31 ,2014. They were divided into a fall group and a non-fall group and were followed up for two years. The incidence and clinic characteristics of falls were analyzed. The risk factors for falls were analyzed by multiple Logistic regression analysis. Results Of the 365 stroke patients included in this study ,falls were observed in 146(40.2％ )patients. The interval between the stroke and the first fall :72(49.3％ )patients had the first fall within 3 months;22(15.1％ )occurred between 4 and 6 months;20 (13.7％ )between 7 and 12 months ;17 (11.6％ )between 13 and 18 months ;and 15 (10.3％ )between 19 and 24 months.A hundred and five(71.9％ )patients fell during daytime and 41 (28.1％ )patients during night.Eighteen(12.3％ )patients had one fall ;65(44.5％ )patients fell 2 to 4 times ;60(41.1％ )patients fell 5 to 10 times ;and 3(2.1％ )patients fell over 10 times.A total of 709 falls were observed.Places of falls :102(69.9％ )falls happened indoors and 44(30.1％ )falls occurred outdoors.Circumstances of falls :27 (18.5％ )patients fell when turning over ;23 (15.8％ )fell when rising from a seating position ;4(2.7％ )patients fell when showering ;15(10.3％ )patients fell while standing ;9(6.8％ )fell when turning around ;56(38.3％ )fell while walking ;and 12(8.2％ )fell while climbing the stairs or running.The severity of falls :52(35.6％ )patients had no injury ;78(53.2％ ) suffered soft tissue injury ;16 (11.0％ )had fractures ;and 78 (53.2％ )had fear of falling.Multiple Logistic regression analysis showed that age(OR=2.41 ;95％ CI :1.69-3.05) ,history of falls(OR =2.85 ;95％ CI :1.46-3.81) ,history of stroke(OR=1.87 ;95％ CI :1.12-2.79) ,right hemiplegia(OR=2.37 ;95％ CI :1.62-4.59) ,left hemiplegia(OR= 2.47 ;95％ CI :1.46-4.78) ,paraplegia(OR= 2.55 ;95％ CI :1.57-4.98) ,visual impairment(OR=2.35 ;95％ CI :1.35-6.62) ,apraxia(OR=2.53 ;95％ CI :1.42-5.63) ,unilateral spatial neglect (OR=3.34 ;95％ CI :2.82-6.34) ,use of psychotropic medications (OR= 1.76 ;95％ CI :1.11-1.98) ,impaired physical mobility (OR = 1.58 ;95％ CI :1.82-2.91) ,low MMSE scale(OR = 3.42 ;95％ CI :1.38-7.41) ,low Barthel Index score(OR = 2.83 ;95％ CI :0.97-4.68) ,BBS scale<45(OR=2.48 ;95％ CI :1.27-4.18) ,TUG>15seconds(OR=3.56 ;95％ CI :1.91-5.23) ,and lack of rehabilitation therapy (OR=3.42 ;95％ CI :1.38-7.41)were independent predictors for falls(all P<0.05). Conclusions Falls are common among elderly patients within two years after stroke.Most falls happen indoors ,during daytime and while moving.Age ,history of falls ,history of stroke ,hemiplegia ,visual impairment ,apraxia ,unilateral spatial neglect ,use of psychotropic medications ,walk with a walker ,low MMSE scale ,low Barthel Index score ,BBS scale<45 ,TUG>15 seconds ,and lack of rehabilitation therapy are independent risk factors for falls after stroke.