Objective To explore the effects of amniotic lacrimal duct stenting on the prevention of dry eye in castrated rabbits.Methods Thirtysix healthy male rabbits were selected,the third eyelid were cut off and antiinfection treatment were given,which were randomly divided into 3 groups (12 cases in each group),the castrated male rabbits models were made.Among them,group A was negative control group,group B was dry eye model group,group C was group of lacrimal amniotic membrane group.At 2 weeks before implantation of amniotic lacrimal duct stent,2 weeks,4 weeks and 6 weeks after implantation,the fluorescent (FL) examination,Western blot,Schirmer I examination,immunofluorescence staining and corneal confocal microscopy were performed.Results The levels of tear secretion and FL in the three groups among different time points were significantly different (F=7.126,P =0.009;F =9.658,P =0.016),and there were significant differences among three groups (F =12.582,P =0.005;F =13.187,P =0.013).The tendency of tear secretion and FL in the three groups were also significantly changed (F =8.531,P =0.007;F =10.652,P =0.019).The epithelial basal cells at 6 weeks after implantation in three groups were 3811 ±414,3820 ± 314,2789 ± 353,and the density of inflammatory cells was 266 ±28,266 ± 29,67 ± 13,there were significant differences among three groups (F =13.442,P =0.012;F =9.231,P =0.021).The K1 6 staining in the duct epithelium were negative,and the expression of α-SMA in the lacrimal duct tissue of group A,B and C was not changed at all time points after implantation of amniotic lacrimal stent,and there was no significant difference (F =14.681,P =0.002).Conclusion The amniotic lacrimal stent implantation has certain effect on the prevention of dry eye in rabbit.

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 observe the antibacterial effect of Ag +-loaded TiO 2 (Ag -TiO 2) and Ag -TiO 2 coated endotracheal tube (ETT) on the bacterial biofilm (BF) of Staphylococcus aureus. Methods:2, 3-bis-(2-methoxy- 4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) colorimetric method was used to detect minimal inhibitory concertation (MIC) of Ag-TiO 2 for inhibition of BF of Staphylococcus aureus. The Ag -TiO 2 coated ETT were prepared, and divided into 11 mg/L, 8 mg/L, 5 mg/L, 2 mg/L and 0 mg/L ETT group, according to the concentration gradient, then impregnated in the liquid with Staphylococcus aureus at a concentration of 1.0×10 9cfu/L. The influence of antibacterial coated ETT on the formation of Staphylococcus aureus BF was determined by detecting the colonies of bacteria and BF on the ETT. Results:Ag-TiO 2 had a significant inhibitory effect on Staphylococcus aureus BF in a concentration -dependent manner, and its MIC was 10 mg/L. Ag -TiO 2 coated ETT has significant anti -Staphylococcus aureus BF effect, and the higher the concentration, the stronger the effect. The absorbance ( A) values of Ag -TiO 2 5 mg/L, 8 mg/L, 11 mg/L ETT groups were significantly lower than that in control group (0.176±0.004, 0.147±0.002, 0.094±0.002 vs. 0.267±0.045, all P < 0.05). The inhibitory rates of Ag -TiO 2 2 mg/L, 5 mg/L, 8 mg/L ETT groups were increased gradually, and 11 mg/L Ag -TiO 2 coated ETT group had the highest inhibitory rate for BF, the inhibitory rates were 6.4%, 34.1%, 44.9% and 64.8%, respectively. Conclusion:Both Ag-TiO 2 and Ag-TiO 2 coated ETT have significant inhibitory effects on Staphylococcus aureus BF.

Background::Although various therapies have been developed to treat malalignment in osteoarthritic knees, the pattern of malalignment progression is still unclear. This study aimed to identify homogeneous subgroups with distinct trajectories of malalignment progression in subjects with symptomatic knee osteoarthritis (KOA) and to determine corresponding risk factors.Methods::Eight-year follow-up (from 2004 to 2012) data on 1252 participants with symptomatic KOA from the Osteoarthritis Initiative were included. Varus/valgus angle progression was characterized by group-based trajectory models. Time-varying covariates were introduced into the model to investigate how they affected trajectories. Multinomial logistic regression for trajectory group membership was applied to ascertain risk factors.Results::Five subgroups were identified. Participants in the varus worsening trajectory ( n = 166) or valgus worsening trajectory ( n = 118) proceeded to worsen malalignment over time. The neutral trajectory ( n = 378), varus stable trajectory ( n = 328), and valgus stable trajectory ( n = 262) maintained close to the initial varus/valgus angle over 8 years. Higher baseline Kellgren and Lawrence grade (odds ratio [OR] = 4.35, P < 0.001 for varus; OR= 3.85, P < 0.001 for valgus) and "severe" baseline malalignment (OR = 13.57, P < 0.001 for varus; OR = 23.04, P < 0.001 for valgus) were risk factors for worsening trajectories. The cutoff point of the baseline varus/valgus angle to discriminate between stable or worsening trajectory was -4.5° for varus and 3.6° for valgus. Conclusions::This study identified the malalignment progression pattern — minor malalignment (-4.5° to +3.6°) tends to remain stable, while major baseline malalignment is likely to progress. This provides a reference for therapy to prevent malalignment from deteriorating and emphasizes the necessity of determining the trigger factors for malalignment onset.

Objective: To investigate the effect of different mechanisms of liver-protection drugs in clinic and compare which one is best for the proliferation of irradiated HL-7702, laying the basis of liver-protection drugs choose in clinic on theory and practice. Methods: Human liver parenchyma cells HL-7702 were given single 6 MV X ray irradiation at a dose of 10Gy, the cells’ morphology were detected under an inverted microscope at 24h, 48h and 72h. Then, MTT was used to assess the survival rate of the cells to evaluate the effect of the X ray. The representive medicines which mechanism may relate to RILD were chosen and diluted into various concentrations with culture medium according to clinical and relative reports. Different concentrations of medicines were used to protect the cells damaged by the X ray. Comparing the effect with MTT and measure SOD, MDA for the best one. Further research on its protection of oxidative damage. T-test, F test and non- paramiter test were used for statistical analysis. Results: 2.5 mg/ml and 1 mg/ml of magnesium isoglycyrrhizinate both have an effect on the proliferation of liver cells, especially the concentration of 1 mg/ml. The injection of polyene phosphatidyl choline show trivial effect at the concentrations of 250 μmol/L and reduced glutathione(GSH) did not demonstrate relative functions. Further research on the magnesium isoglycyrrhizinate, found its protection at 48h to oxidative damage (P < 0.05), but the effect is weak at 24h and 48h. Conclusions In three kinds of representing medicines, magnesium isoglycyrrhizinate has preferable effects on liver parenchyma cells and show a bright future in the treatment of RILD.

Background: Microsporum canis is a zoonotic disease that can cause dermatophytosis in animals and humans. Objectives: In clinical practice, ketoconazole (KTZ) and other imidazole drugs are commonly used to treat M. canis infection, but its molecular mechanism is not completely understood.The antifungal mechanism of KTZ needs to be studied in detail. Methods: In this study, one strain of fungi was isolated from a canine suffering with clinical dermatosis and confirmed as M. canis by morphological observation and sequencing analysis.The clinically isolated M. canis was treated with KTZ and transcriptome sequencing was performed to identify differentially expressed genes in M. canis exposed to KTZ compared with those unexposed thereto. Results: At half-inhibitory concentration (½MIC), compared with the control group, 453 genes were significantly up-regulated and 326 genes were significantly down-regulated (p < 0.05). Quantitative reverse transcription polymerase chain reaction analysis verified the transcriptome results of RNA sequencing. Gene ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that the 3 pathways of RNA polymerase, steroid biosynthesis, and ribosome biogenesis in eukaryotes are closely related to the antifungal mechanism of KTZ. Conclusions The results indicated that KTZ may change cell membrane permeability, destroy the cell wall, and inhibit mitosis and transcriptional regulation through CYP51, SQL, ERG6, ATM, ABCB1, SC, KER33, RPA1, and RNP genes in the 3 pathways. This study provides a new theoretical basis for the effective control of M. canis infection and the effect of KTZ on fungi.

BACKGROUND:Bone mineral density is the clinical gold standard for determining bone strength,but bone mineral density is less sensitive to changes in bone mass,with large changes in bone mineral density only occurring when bone mass is significantly reduced,so bone mineral density has limited ability to predict changes in bone strength and fracture risk. OBJECTIVE:A model of the normal and osteoporotic hip joint was developed to analyze the stresses and deformation in the hip of normal and osteoporotic patients under single-leg standing conditions. METHODS:A healthy adult female volunteer at the age of 36 years was selected as the study subject.The CT data of the hip joint of this volunteer were obtained and saved in DICOM format.The hip joint model was reconstructed in three dimensions,and the material properties were assigned by the gray value assignment method to obtain the normal and osteoporotic hip joint models according to the empirical formula.The same boundary conditions and loads were set to simulate the stresses and deformation in the normal and osteoporotic hip joints in the single-leg standing position. RESULTS AND CONCLUSION:(1)In the finite element model of the normal and osteoporotic hip,the stress distribution was more concentrated in the medial region of the femoral neck.(2)In the hip bone,the stress distribution was mainly concentrated in the upper part of the acetabulum.(3)The stress peaks in the medial femoral neck and upper acetabulum were larger in the normal hip model than in the osteoporotic hip model,probably due to the reduced bone strength of the osteoporotic bone.(4)The peak Von Mises of both normal and osteoporotic hip models were concentrated on the medial femoral neck,and the peak Von Mises of the hip bone was smaller,indicating that the overall effect of osteoporosis on hip bone stresses was relatively small.(5)In terms of deformation in the single-leg standing position,the maximum deformation in the normal hip model was located at the acetabulum and femoral head,and the maximum deformation was located at the upper part of the greater trochanter of the femur.(6)It is suggested that the finite element analysis method to model the values of parameters related to bone tissue in osteoporosis may improve clinical prediction of bone strength changes and fracture risk.It is explained from the biomechanical view that the intertrochanteric femur and femoral neck are good sites for osteoporotic hip fractures.

BACKGROUND: Patellofemoral joint (PFJ) degeneration has traditionally been regarded as a contraindication to unicompartmental knee arthroplasty (UKA). More recently, some researchers have proposed that PFJ degeneration can be ignored in medial UKA, and others have proposed that this change should be reviewed in PFJ degenerative facets and severity. This study aimed to systematically evaluate the effect of PFJ degeneration on patient-reported outcome measures (PROMs) and revision rates after medial UKA. METHODS: Electronic databases (PubMed, Embase, Web of Science, etc.) were searched for studies assessing the influence of PFJ degeneration on medial UKA. A random-effects meta-analysis was conducted for the Oxford knee score (OKS), Knee society score (KSS), and revision rates and stratified by PFJ degenerative facets (medial/lateral/trochlear/unspecified), severe PFJ degeneration (bone exposed), and bearing type (mobile/fixed). Heterogeneity was assessed by the Cochran Q test statistic and chi-squared tests with the I-squared statistic. RESULTS: A total of 34 articles with 7007 knees (2267 with PFJ degeneration) were included (5762 mobile-bearing and 1145 fixed-bearing and 100 unspecified). Slight to moderate degenerative changes in the medial and trochlear facets did not decrease the OKS and KSS, and only lateral facets significantly decreased the OKS (mean difference [MD] = -2.18, P   <  0.01) and KSS (MD = -2.61, P   <  0.01). The severity degree of PFJ degeneration had no additional adverse effect on the OKS, KSS, or revision rates. For mobile-bearing UKA, only lateral PFJ degeneration significantly decreased the OKS (MD = -2.21, P  < 0.01) and KSS (MD = -2.44, P  < 0.01). For fixed-bearing UKA, no correlation was found between PROMs/revision rates and PFJ degeneration. CONCLUSION For medial mobile-bearing UKA, slight to moderate degenerative changes in the PFJ, except lateral facet, did not compromise PROMs or revision rates. For medial fixed-bearing UKA, although it might not be conclusive enough, PROMs or revision rates were not adversely affected by PFJ degeneration (regardless of the facet).
Humans ; Arthroplasty, Replacement, Knee ; Patellofemoral Joint/surgery* ; Treatment Outcome ; Osteoarthritis, Knee/surgery* ; Knee Prosthesis ; Bone Diseases ; Knee Joint/surgery* ; Retrospective Studies

OBJECTIVE To provide reference for developing pharmacovigilance and constructing an active surveillance system with extensive participation of pharmaceutical enterprises in China. METHODS Retrieving the literature and data from databases such as CNKI ，PubMed，and the official website of observational medical outcomes partnership （OMOP），the mechanism of pharmaceutical enterprises ’participation and its operation mode were investigated ，while specific path and code of conduct for pharmaceutical enterprises to participate in active surveillance system were analyzed. Finally ，the corresponding suggestions were put forward according to the actual situation of China. RESULTS & CONCLUSIONS Pharmaceutical enterprises in OMOP participated in project construction and operation through public private partnership （PPP）mechanism，and played the role of project funding ，project governance and project research. Pharmaceutical enterprises participating in OMOP need to carry out activities in accordance with the code of conduct of extensive cooperation ，transparency and openness and the protection of patient privacy. In the future practice of active surveillance system in China ，it is necessary to promote the relevant legislation of active monitoring system ，emphasize the responsibility of active surveillance of pharmaceutical enterprises ，establish a PPP mechanism of industry-university-research integration ，form a good governance ecology and strengthen the protection of patients ’privacy.

Objective:To investigate the specimen quality of intersphincteric resection with transabdominal transanal mixed approach for rectal cancer in the Chinese Transanal Total Mesorectal Excision Registry Collaborative (CTRC) database.Methods:The retrospective case-control study was conducted. Based on the concept of real-world research, the clinicopathological data of 281 pati-ents with rectal cancer in the CTRC database who underwent intersphincteric resection with trans-abdominal transanal mixed approach in 19 medical centers, including the Beijing Friendship Hospital of Capital Medical University et al, from November 15,2017 to December 31,2023 were collected. There were 196 males and 85 females, aged 61(range, 27-87)years. Observation indicators: (1) preoperative examinations; (2) neoadjuvant therapy; (3) postoperative examinations; (4) analysis of influencing factors for positive circumferential margin in surgical specimen of intersphincteric resec-tion for rectal cancer. Measurement data with normal distribution were represented as Mean±SD. Measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers or percentages. The chi-square test was used for univariate analysis. Logistic regression model was used for multivariate analysis. Results:(1) Preoperative examinations. Of the 281 patients, 234 cases underwent preoperative pelvic magnetic resonance imaging (MRI) examina-tion. There were 2 cases in clinical stage T0, 3 cases in clinical stage T1, 58 cases in clinical stage T2, 137 cases in clinical stage T3, 24 cases in clinical stage T4, 3 cases in clinical stage Tx, 7 cases missing clinical T staging data. There were 87 cases in clinical stage N0, 68 cases in clinical stage N1, 60 cases in clinical stage N2, 9 cases in clinical stage Nx, 10 cases missing clinical N staging data. There were 30 cases with mesorectal fascia invasion, 53 cases with extramural venous invasion. The distance from lower margin of tumor to anal margin was 41.9(range, 1.0-80.0)mm. (2) Neoadjuvant therapy. Of the 281 patients, 125 cases underwent neoadjuvant therapy, including 39 cases receiving chemo-therapy alone, 6 cases receiving short-course simultaneous chemoradiotherapy, 5 cases receiving short-course simultaneous chemoradiotherapy and delayed surgery, 48 cases receiving long-course simultaneous chemoradiotherapy, 2 cases receiving other treatments, and 25 cases missing neoadju-vant therapy data. (3) Postoperative examinations. Of the 281 patients, 249 cases achieved R 0 resection, 9 cases achieved R 1 resection, and there were 23 cases missing surgical margin data. The maximum tumor diameter, the number of lymph nodes harvested and positive rate of vessel carcinoma embolus were 30.0(range, 0.5-200.0)mm, 13(range, 0-70) and 27.55%(73/265) in 281 patients. There were 252 patients with circumferential margin records, showing positive in 15 cases, with a positive rate as 5.95%(15/252). The minimum distance from deep part of tumor to circumferential margin was 7.0(range, 0-150.0)mm in 252 patients. There were 85 cases with distal margin records, showing positive in 1 case, and the distance from lower margin of tumor to distal margin was 10.0(range, 0-202.0)mm. There were 273 patients with specimen integrity records, which showed intact specimen in 208 cases, fair specimen in 58 cases, poor specimen in 4 cases, unevaluated specimen in 3 cases. There were 7 cases with rectal perforation. Of the 281 patients, cases in pathological stage T0, Tis, T1, T2, T3, T4 were 14, 5, 22, 107, 113, 12, respectively, and there were 8 cases missing pathological T staging data. Of the 281 patients, cases in pathological stage N0, N1a, N1b, N1c, N2a, N2b were 176, 27, 27, 11,20, 12, respectively, and there were 8 cases missing pathological N staging data. Of the 281 patients, there were 4 cases with distant metastasis, 262 cases without distant metastasis, 5 cases not evaluated, and 10 cases missing tumor metastasis data. Of the 125 patients undergoing neoadjuvant therapy, there were 85 cases with tumor regression grade records, including 16 cases as grade 1, 27 cases as grade 2, 19 cases as grade 3, 15 cases as grade 4, 8 cases as grade 5. (4) Analysis of influencing factors for positive circumferential margin in surgical specimen of intersphincteric resection for rectal cancer. Results of univariate analysis showed that preoperative T staging on preoperative pelvic MRI, mesorectal fascia invasion, extramural venous invasion, pathological T staging, and pathological N staging were related factors for positive circumferential margin in surgical specimen of intersphincteric resection for rectal cancer ( P<0.05). Conclusions:Intersph-incteric resection with transabdominal transanal mixed approach has good specimen quality and low positive rate of surgical margin. T staging on preoperative pelvic MRI may be related to positive circumferential margin after intersphincteric resection for rectal cancer.