Objective: To establish a method for determining the molecular weight and molecular weight distribution of Poly(Lactide-co-Glycolide Acid) (PLGA) using Size Exclusion Chromatography-Refractive Index-Multiangle Laser Light Scattering (SEC-RI-MALLS) and Size Exclusion Chromatography-Refractive Index (SEC-RID), and to compare the results obtained from these two methods.
Methods: For SEC-RI-MALLS, tetrahydrofuran was used as the mobile phase, Shodex GPC KF-803L was employed as the chromatographic column with a flow rate of 1 mL·min^-1, column temperature at 30 ℃, and an injection volume of 100 μL. For SEC-RID, tetrahydrofuran was also used as the mobile phase, Agilent PLgel 5 μm MIXD-D was used as the chromatographic column with a flow rate of 1 mL·min^-1, column temperature at 30 ℃, differential detector temperature at 35 ℃, and an injection volume of 20 μL. The molecular weight and molecular weight distribution were calculated using Agilent’s GPC software. The newly established methods were validated methodologically, and the molecular weight and molecular weight distribution of 13 batches of samples were determined.
Results: The precision, accuracy, stability, and repeatability tests for SEC-RI-MALLS showed RSD values of 1.35%, 1.58%, 1.53%, and 1.26%, respectively. The SEC-RID method exhibited good linearity (r=0.999 9), with RSD values for precision, accuracy, stability, and repeatability tests (n=6) of 2.05%, 1.62%, 1.30%, and 2.97%, respectively. The results obtained from SEC-RI-MALLS were lower than those from SEC-RID, and the molecular weight distribution coefficient was smaller, but the results from the paired T-test performed with the value measured by SEC-RID method and the value measured by SEC-RI-MALLS method multiplied a conversion coefficient of 1.5 showed no significant difference between the two methods.
Conclusion: Both methods are stable and reliable, and can be used for the determination of PLGA molecular weight and molecular weight distribution based on the specific situations.

Objective To analyze the differentially expressed long non-cording RNA (lncRNA) in human colon carcinoma tissue and paracancerous normal colon tissue. Methods Total RNA from the colon carcinoma tissues and paracancerous normal colon tissues of 6 patients from July to August 2015 in Beijing Chao-Yang Hospital, Capital Medical University were prepared respectively. The mRNA of total RNA was amplified, labeled and purified. Hybridization was performed with the profile chip, and the data were normalized and analyzed. Results Compared with normal tissues, 1 339 lncRNAs expressed differentially (P < 0.05), 53 lncRNAs were significantly differential (fold change > 2) in colon carcinoma tissues, in which 41 lncRNAs were up-regulation and 12 lncRNAs were down-regulation.Three lncRNAs had more than 3 times changes. Conclusion Obvious changes of lncRNA expression profile are observed in the pathogenesis of colon carcinoma,suggesting that lncRNA may be related to the progress of colon carcinoma.

Objective To explore the clinical characteristics and treatment of abdominal cocoon.Methods Clinical data of 5 cases with abdominal cocoon in our hospital from October 2015 to February 2017 were analyzed.Results 5 patients with abdominal cocoon were recruited,including 3 males and 2 females.Of the 5 patients,one with gastric cancer,1 with colon cancer,2 with rectal cancer and 1 with cryptorchidism.All the patients have no symptoms of intestinal obstruction.Laparotomy revealed that all or part of small intestine had been wrapped in a layer of tough fibrous membrane.Excision of primary lesion without lysis of adhesions were done.No symptoms of intestinal obstruction and intestinal fistula occurred after operation.Conclusions The preoperative diagnosis of abdominal cocoon is difficult.It is often inadvertently found in the operation,asymptomatic patients,do not need treatment.

Objective To investigate the application value of biological mesh in the pelvic floor reconstruction of extralevator abdominoperineal excision (ELAPE) for advanced low rectal cancer (RC).Methods The retrospective cohort study was conducted.The clinicopathological data of 228 patients with advanced low RC who underwent ELAPE in the Beijing Chaoyang Hospital of Capital Medical University between August 2008 and December 2016 were collected.Of 228 patients,174 using biological mesh closure and 54 using primary closure were respectively allocated into the biological mesh group and primary closure group.Observation indicators:(1)intra-and post-operative situations;(2) postoperative complications (including short-term and long-term complications);(3) follow-up and survival situations.Follow-up using outpatient examination and telephone interview was performed to detect postoperative long-term complications,tumor recurrence or metastasis and overall survival up to December,2017.Measurement data with normal distribution were represented as（ x） ±s,and comparison between groups was analyzed using the independent-sample t test.Measurement data with skewed distribution were described as M (range),and comparison between groups was analyzed using the nonparametric test.Comparisons of count data were evaluated by the chi-square test or Fisher exact probability.Results (1)Intra-and post-operative situations:all the patients underwent successful ELAPE.The perineal operation time,time of indwelling perineal drainage-tube and hospital expenses were respectively (60 ± 50)minutes,(11.6 ± 2.4) days,(57 781± 11 337) yuan in the biological mesh group and (50±21) minutes,(8.9± 1.7) days,(53 714± 13 395)yuan in the primary closure group,with statistically significant differences between groups (t =3.327,7.691,-2.203,P＜0.05).The total operation time and duration of postoperative hospital stay were respectively (242±53) minutes,(13.0±5.0) days in the biological mesh group and (228±51) minutes,(12.0±5.0) days in the primary closure group,with no statistically significant difference between groups (t =1.701,1.309,P＞0.05).(2) Postoperative complications:26 and 19 patients in the biological mesh group and primary closure group had respectively perineal wound complications (1 patient combined with multiple complications),showing a statistically significant difference between groups (x2 =10.660,P＜0.05).The perineal wound infection,perineal hernia and disruption of perineal wound were respectively detected in 20,6,1 patients in the biological mesh group and 12,7,3 patients in the primary closure group,showing statistically significant differences between groups (x2 =3.931,5.282,P＜0.05).(3) Follow-up and survival situations:174 patients in the biological mesh group were followed up for 64 months (range,13-112 months),and 54 patients in the primary closure group were followed up for 51 months (range,23-76 months).The local recurrence rate,distal metastasis rate and overall survival rate were respectively 5.17％ (9/174),20.11％ (35/174),77.59％ (135/174) in the biological mesh group and 7.41％(4/54),24.07％(13/54),79.63％(43/54) in the primary closure group,with no statistically significant difference between groups (x2 =0.080,0.389,0.101,P＞0.05).Conclusions The biological mesh in the pelvic floor reconstruction of ELAPE for advanced low RC is safe and feasible.Compared with primary closure,biological mesh closure will extend perineal operation time and time of indwelling perineal drainage-tube,and increase hospital expenses,but doesn't affect total operation time and duration of postoperative hospital stay,meanwhile,it can also reduce the overall perineal wound complications,especially in perineal wound infection,perineal hernia and disruption of perineal wound.

OBJECTIVE: To compare the safety and feasibility between modified circumferential purse-string closure and conventional primary linear closure of the wound following loop stoma reversal. METHODS: Clinical data of 88 consecutive patients who underwent loop colostomy or loop ileostomy closures at our hospital from July 2011 to June 2013 were retrospectively analyzed. Among them, 43 cases underwent modified purse-string technique (modified purse-string group), 45 cases underwent direct suture (direct suture group). The operation method of modified purse-string suture was as follows: (1) the circumferential subcutaneous adipose tissue was sutured with the absorbable suture, avoiding tightening at knotting and retaining a 1 cm pore;(2)absorbable suture was used to perform purse-string suture of the dermis, retaining a 0.5 cm central pore when knotting; (3) a rubber drain was placed through the pore. The clinical parameters, surgical results and postoperative complication of two groups were recorded and compared. RESULTS: There were 56 males and 32 females with age of (65.0±11.5) years old. Seventy-nine cases were malignant tumors, 6 were benign tumors and 3 were traumatic. There was no significant difference in the baseline data between two groups (all P>0.05). Compared with the direct suture group, the modified purse-string group had significantly lower wound infection rate [7.0%(3/43) vs. 24.4%(11/45), χ²=5.015, P=0.025]; significantly shorter postoperative hospital stay (mean 7.1 days vs. 8.6 days, t=-2.656, P=0.010); significantly lower total hospitalization costs (mean 25 668.4 yuan vs. 27 718.1 yuan, t=-2.488, P=0.015); however, the wound healing time of the modified purse-string group was significantly longer (mean 22.0 days vs. 13.0 days, t=5.701, P<0.001). The average healing time of the wounds in the direct suture group was 29.8 days, which was significantly longer than that of the first-stage healing cases (7.5 days, t=-15.446,P<0.001). The average wound healing time of the infected cases in the modified purse-string suture group was 22.0 days, compared with 22.1 days in the first-stage healing cases, the difference was not statistically significant(t=0.077,P=0.943). CONCLUSIONS Modified purse-string closure after loop stoma reversal is an appropriate technique with lower stoma site infection rate, shorter postoperative hospital stay and lower hospitalization cost than conventional primary closure, although wounds may take longer to heal in this approach.
Aged ; Bacterial Infections ; prevention & control ; Colostomy ; Female ; Humans ; Ileostomy ; Intestines ; surgery ; Male ; Middle Aged ; Retrospective Studies ; Surgical Stomas ; Suture Techniques ; standards ; Sutures ; Wound Healing

OBJECTIVE: To evaluate the safety and feasibility of neoadjuvant chemotherapy prior elective surgery following self-expanding metallic stents (SEMS) for complete obstructive left hemicolon cancer. METHODS: This prospective, multicenter, open-labelled trial was approved by the Ethics Committee of Beijing Chaoyang Hospital, Capital Medical University(2016-ke-161-1) and registered in Clinicaltrials.gov (NCT02972541). INCLUSION CRITERIA: (1)age between 18 and 75 years old;(2) adenocarcinoma confirmed by pathology;(3) left hemicolon cancer confirmed by clinical manifestations and imaging examinations with the distance to anal verge > 15 cm; (4) resectable cancer evaluated by imaging examination without distant metastasis; (5) Eastern Cooperative Oncology Group (ECOG) score ≤ 1 or Karnofsky Performance Scale (KPS) > 70, indicating tolerance of neoadjuvant chemotherapy and operation; (6) absence of chemotherapy or radiotherapy within past six months; (7) bone marrow system and hepatorenal function: hemoglobin ≥ 90 g/L, neutrophil ≥ 1.5×10/L, platelet ≥ 80×10/L, total bilirubin ≤ 1.5×ULN(upper limits of normal), serum transaminase ≤ 2.5×ULN, serum creatinine ≤ 1.0×ULN, endogenous creatinine clearance rate > 50 ml/min; (8) sign for informed consent. EXCLUSION CRITERIA: (1) multiple primary colorectal cancer; (2) rejection of operation;(3) presenting peritonitis or bowel perforation before SEMS; (4) unqualified conditions proved by inspector from registration data. According to inclusion criteria, 62 consecutive patients receiving neoadjuvant chemotherapy prior to elective surgery following SEMS for complete obstructive left hemicolon cancer from Beijing Chaoyang Hospital of Capital Medical University (n=31), Qilu Hospital of Shandong University (n=14), the Third Xiangya Hospital of Central South University (n=13), Zhongnan Hospital of Wuhan University (n=2), the Fourth Hospital of Hebei Medical University (n=2) between December 2015 and December 2017 were prospectively enrolled in this study. Patients were divided into neoadjuvant chemotherapy group and elective surgery group according to the investigator's clinical experience and patient's preference. Patients in the elective surgery group received surgery within one to two weeks after SEMS placement without neoadjuvant chemotherapy. Those in the neoadjuvant chemotherapy group received 2 cycles of CapeOX or 3 cycles of mFOLFOX6 neoadjuvant chemotherapy within one to two weeks after SEMS placement, and then underwent surgery within 3 weeks after finishing neoadjuvant chemotherapy. Data between groups were compared using Student t-test, chi-square analysis or Fisher exact test analysis, including basic clinical informations, operational conditions and postoperative complications. The adverse reactions during the neoadjuvant chemotherapy were recorded. Surgical difficulty was assessed using visual analog scales ranging from 1 to 10, where 1 represented the lowest and 10 the highest degree of surgical difficulty, as judged by the surgeon. RESULTS: The study included 38 males and 24 females with mean age of (64.8±8.8) years. The clinical baseline data between 2 groups were not significantly different (all P>0.05) except the average time interval between SEMS and surgery was significantly longer in neoadjuvant chemotherapy group [(61.6±13.5) days vs. (10.4±5.2) days, t=16.679, P<0.001]. There was no stent migration in either group. Three patients had perforation in the elective surgery group; one patient had perforation and one had obstruction in the neoadjuvant chemotherapy group; and all these patients received emergent surgery. Adverse reactions of neodajuvant chemotherapy were mainly degree 1 and 2 except one patient with degree 3 diarrhea. Patients in neoadjuvant chemotherapy group had significantly lower rate of stoma [4.8%(1/21) vs. 34.1%(14/41), χ²=6.538, P=0.011], higher rate of laparoscopic surgery [71.4%(15/21) vs. 36.6%(15/41), χ²=6.751, P=0.009], shorter mean operative time (147 minutes vs. 178 minutes, t=-3.255, P=0.002), less mean intraoperative blood loss (47 ml vs. 127 ml, t=-4.129, P<0.001), lower degree of surgical difficulty(3.3 vs. 5.6, t=-5.091, P<0.001), shorter mean postoperative exhausting time (56.2 hours vs. 69.0 hours, t=-2.891, P=0.006), and shorter mean postoperative hospital stay (8.5 days vs. 13.5 days, t=-2.246, P=0.028) as compared with patients in the elective surgery group. Surgical site infection rate and anastomotic leakage rate did not differ significantly between two groups(all P>0.05). CONCLUSION Neoadjuvant chemotherapy prior elective surgery following SEMS is a relatively safe and feasible approach in the treatment for obstructive left hemicolon cancer, and is associated with less stoma, more laparoscopic surgery, shorter operative time, less blood loss, lower surgical difficulty, and faster postoperative recovery as compared with conventional elective surgery.
Aged ; Colorectal Neoplasms ; surgery ; therapy ; Female ; Humans ; Intestinal Obstruction ; Male ; Middle Aged ; Neoadjuvant Therapy ; Prospective Studies ; Stents ; Treatment Outcome

OBJECTIVETo evaluate the laparoscopy combined with transperineal extralevator abdominoperineal excision (TP-ELAPE) for locally advanced low rectal caner.

METHODSClinical data of 12 patients with locally advanced low rectal cancer undergoing laparoscopy combined with TP-ELAPE in our department from May 2013 to March 2015 were retrospectively analyzed. There were 8 male and 4 female patients with median aged of 63 (46 to 72) years. The median distance from tumor lower margin to anal verge was 3.5(2.0 to 4.0) cm. A self-made transanal suit for minimally invasive operation was used to make a sealed lacuna outside the sphincter, thus laparoscope can be applied to perform transperineal operation.

RESULTSAll the patients underwent operations successfully without conversion to open abdominal operation. The median operating time was 206 (180 to 280) minutes with perineal operating time 95(80 to 120) minutes. The median intraoperative blood loss was 120(50 to 200) ml. The median postoperative hospital stay was 12(9 to 18 ) days. Postoperative pathology revealed that all circumferential margins (CRM) were negative. The area of sample horizontal section was (2 824±463) mm(2), and of outer muscularis propria was(2 190±476) mm(2). Postoperative complications included chronic sacrococcygeal region pain in 2 cases, urinary retention in 3 cases, perineal wound infection in 1 case. No perineal seroma, perineal hernia, wound dehiscence and sinus tract formation were observed. Among 8 patients with preoperative normal sexual function, sexual dysfunction occurred in 2 patients. There was no local recurrence and metastasis during a median follow-up of 21(12 to 34) months.

CONCLUSIONLaparoscopy combined with TP-ELAPE has the potential to simplify the operation procedure for low rectal cancer, can ensure the radical treatment and safety of operation, and may be carried out in experienced centers.

Abdomen ; Aged ; Anal Canal ; Blood Loss, Surgical ; Digestive System Surgical Procedures ; methods ; Female ; Humans ; Laparoscopy ; Length of Stay ; Male ; Middle Aged ; Neoplasm Recurrence, Local ; Operative Time ; Perineum ; Postoperative Complications ; Postoperative Period ; Rectal Neoplasms ; surgery ; Rectum ; Retrospective Studies

Objective To investigate the feasibility of a noval anterior cubital approach for the coronoid via flexor?prona?tor teres interval and assess the clinical result. Methods Five formalin?fixed adult cadaver elbows were used. Through a single universal anteromedial longitudinal skin incision, the coronoid tip was exposed via pronator and flexor carpiradialis interval, and coronoid anteromedial facet and base via palm longus and flexor carpi ulnaris interval. The distances from the entry point to the muscles or branching point of the nerves to the line passing through medial and lateral epicondyles, as well as the length were mea?sured with regard to the motor nerve branches arising from median nerve to pronator teres, flexor carpiradialis, palm longus and flexor digiti superficialis, as well as the most proximal two motor branches to flexor carpi ulnaris arising from ulnar nerve. From September 2013 to August 2014, 4 male patients with ulnar coronoid fracture were treated operatively through the above anterior cubital approach in our hospital. They were all left side involved, with an average age of 32 years (range, 16-42 years). According to O’Driscoll classification, there were two cases of type Ib and two cases IIb respectively. They were all treated by open reduction and internal fixation through flexor?pronator teres interval. Results At cubital fossa, there were 2-3 branches to the pronator teres mostly, 1 branch to flexor carpiradialis and palm longus arising from median nerve. The branch to the flexor digiti superficia?lis usually was long and thick, and divided into 2-5 short twigs near muscle. The branch to palm longus had the same trunk with that to flexor digiti superficialis. The branch to flexor digiti superficialis was the most proximal among those passed through the in?terval of pronator teres and flexor carpiradialis, and its entry point to the muscle had an averaged distance of 37.22 mm to the line passing through medial and lateral humeral epicondyles. It was optimal to expose coronoid tip through the interval of pronator teres and flexor carpiradialis. It was safe to expose coronoid proximal to the branch to flexor digiti superficialis. While, it was better to expose the anteromedial facet and base of corocoid through the interval of palm longus and flexor carpiulnaris via median and ul?nar nerve interface. All of the four patients were followed up for an average period of 9 months. They all achieved bone union from 6 weeks to 3months (mean, 9 weeks). All the patients obtained excellent result according to the modified An&Morrey elbow per?formance index with scores from 94 to 100. Conclusion The novel anteromedial cubital approach via flexor?pronator teres is opti?mal for exposure of coronoid.

OBJECTIVETo investigate the incidence of surgical site infection (SSI) and risk factors in colorectal cancer surgery patients.

METHODSBetween October 2003 and October 2013, 1 381 consecutive patients with colorectal cancer managed surgically with primary anastomosis were included in the study. There were 762 male and 619 female patients with mean body mass index (BMI) was (27.7 ± 3.7) kg/m², aged from 20 to 90 years with a median of 67 years. Patients undergoing emergency surgery and requiring stoma creation were excluded. The patients' characteristics, surgical conditions and prognosis were recorded. Univariate and multiple logistic regression analysis were used to identify any variable predictive factors of SSI.

RESULTSOne hundred twenty-six (9.12%) cases developed incisional SSI. The occurrence time for SSI was from 2 to 20 days, mean (6.7 ± 2.9) days. According to multivariable logistic regression analysis, BMI (OR = 1.058, P = 0.030), intraoperative contamination (OR = 10.549, P = 0.000) and open operation as compared with a laparoscopic procedure (OR = 2.111, P = 0.001) were significant independent predictors of incisional SSI. There was a significant decrease in incisional SSI in wound protectors group (OR = 1.646, P = 0.012).

CONCLUSIONBMI and intraoperative contamination are independent predictors of incisional SSI, and wound protectors and laparoscopic surgery are associated with a lower incidence of incisional SSI following colorectal cancer surgery.

Adult ; Aged ; Aged, 80 and over ; Anastomosis, Surgical ; Body Mass Index ; Colorectal Neoplasms ; surgery ; Colorectal Surgery ; Female ; Humans ; Logistic Models ; Male ; Middle Aged ; Prognosis ; Retrospective Studies ; Risk Factors ; Surgical Wound Infection ; etiology ; Young Adult

Objective To explore the feasibility of the extended inferior meatal maxillary antrostomy through inferior turbinate reversing approach.Methods Eight patients underwent extended inferior meatal maxillary antrostomy through inferior turbinate reversing approach for maxillary sinus lesions.The indications,surgical management and outcomes of the surgery were presented.Results There were 2 cases of maxillary dentigerous cyst with oroantral fistula,2 cases of antrochoanal polyp,2 cases of maxillary sinus inverted papillomas,1 case of odontogenic maxillary sinusitis with oroantral fistula,and 1 case of maxillary sinus mucocele.All patients underwent extended inferior meatal maxillary antrostomy through inferior turbinate reversing approach without intraoperative complication,with good access to the lesions.Complete resection could be achieved through this approach,no postoperative complications occurred except one patient had a delayed wound healing of inferior turbinate,all patients were free of recurrence with the average postoperative follow-up of 7.8 months (range 4-12 months).Conclusion The extended inferior meatal maxillary antrostomy through inferior turbinate reversing approach is recommended for some maxillary pathology owing to its good access to the lesions and complete resection.