BACKGROUND:Acellular vascular scaffolds can mimic the microstructure and function of native blood vessels,but some extracellular matrix loss occurs during their preparation,which affects their hemocompatibility.Therefore,it is necessary to modify them to improve their hemocompatibility. OBJECTIVE:To assess the hemocompatibility of acellular vascular scaffold prepared by Triton-x100/heparin sodium treatment. METHODS:The abdominal aorta was taken from SD rats and randomly divided into control and experimental groups.The control group was treated with Triton-x100 for 48 hours.The experimental group was treated with Triton-x100 for 48 hours and then treated with heparin sodium.The morphology and hydrophilicity of the two groups of acellular vascular scaffolds were detected.The hemocompatibility of the two groups of acellular vascular scaffold was evaluated by recalcification coagulation time test,platelet adhesion test,dynamic coagulation time test,hemolysis test,and complement activation test. RESULTS AND CONCLUSION:(1)Scanning electron microscopy showed that the surface of the two groups of vascular scaffolds was relatively intact,and a large number of fiber filaments appeared on the surface of the scaffolds after decellularity treatment,and the surface microstructure changed significantly.The water contact angle of the two groups of vascular scaffolds was smaller than that of natural vessels(P<0.000 1).There was no significant difference in water contact angle between the two groups(P>0.05).(2)The coagulation time of vascular scaffold was longer in the experimental group than in the control group(P<0.05).The number of platelets attached to the scaffold membrane was less in the experimental group than that in the control group(P<0.000 1).The coagulation index was greater in the experimental group than that in the control group(P<0.01),and the complement level was lower in the experimental group than that in the control group(P<0.001).The hemolysis rate of the two groups was lower than 5%of the national standard.(3)To conclude,acellular scaffold treated with Triton-x100/heparin sodium has excellent hemocompatibility.

Objective:To investigate the clinicopathological characteristics and prognostic factors of gastrointestinal stromal tumor (GIST) with initial surgical resection.Methods:The retro-spective cohort study was conducted. The clinicopathological data of 847 GIST patients who under-went initial surgical resection in Tianjin Medical University Cancer Institute & Hospital from January 2011 to December 2020 were collected. There were 405 males and 442 females, aged (60±10)years. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the t test. Measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers or percentages, and comparison between groups was conducted using the chi-square test. Comparison of ordinal data was conducted using the nonparameter rank sum test. The Kaplan-Meier method was used to calculate survival rates. Univariate analysis was conducted using the Log-rank test. Multivariate analysis was conducted using the COX regression model. Results:(1) Clinicopatholo-gical characteristics. Of 847 patients, the tumor primary location was stomach in 585 cases, jejunum and ileum in 142 cases, duodenum in 76 cases, colorectum in 10 cases, esophagus in 3 cases, and extra-gastrointestinal in 31 cases. There were 13 cases with liver metastasis and 22 cases with abdominal metastasis. The tumor maximum diameter was (7±5)cm, and the number of nuclear divisions was 4(range, 0-60) cells/50 high-power field or 5 mm 2. According to risk classification of National Institutes of Health (NIH), 31 cases were of extremely low risk, 238 cases were of low risk, 213 cases were of moderate risk, 365 cases were of high risk. There were 839 of 847 patients positive for CD117, 788 cases positive for Dog-1, 710 cases positive for CD34, respectively. There were 272 cases with Ki-67 <5%, 214 cases with Ki-67 of 5%- 9%, 198 cases with Ki-67 ≥10%, 163 cases with missing data. R 0 resection was in 814 cases and non-R 0 resection was in 33 cases. (2) Gene testing and postoperative adjuvant therapy of GIST patients. ① Gene testing. Of 847 patients, 424 underwent genetic testing. The proportion of genetic testing was 1.89%(1/53) in 2011, 9.76%(8/82) in 2012, 8.45%(6/71) in 2013, 15.66%(13/83) in 2014, 50.00%(40/80) in 2015, 55.26%(42/76) in 2016, 73.86%(65/88) in 2017, 68.27%(71/104) in 2018, 80.65%(75/93) in 2019, 88.03%(103/117) in 2020, respectively. Of 424 with genetic testing, 338 cases had KIT mutation, 31 cases had PDGFRA mutation, 55 cases were wild type. ② Adjuvant therapy. Of 847 patients, 253 patients underwent postoperative adjuvant therapy. The proportions of postoperative adjuvant therapy were 8.82%(21/238), 41.78%(89/213), 39.18%(143/365) in patients of low risk, moderate risk, high risk. Of 578 patients with moderate to high risk, the proportion of postoperative adjuvant therapy was 15.15%(5/33) in 2011, 14.71%(10/68)in 2012, 22.45%(11/49) in 2013, 29.09%(16/55) in 2014, 41.38%(24/58) in 2015, 46.15%(24/52) in 2016, 32.81%(21/64)in 2017, 60.00%(45/75) in 2018, 60.42%(29/48) in 2019, 61.84%(47/76) in 2020, respectively. Of 253 patients underwent postoperative adjuvant therapy, 247 cases received imatinib had 6 cases received sunitinib. (3) Comparison of clinicopathological characteristics of GIST with non-gastric origin and gastric origin. Of 847 patients, 262 cases had non-gastric origin and 585 cases had gastric origin. There were significant differences in gender, the number of tumor, tumor maximum diameter, Ki-67 index, risk classification of NIH, and R 0 resection between the two groups ( χ2=8.62, 8.40, 12.97, 6.57, Z=-6.15, χ2=17.19, P<0.05). (4) Analysis of influencing factors for recurrence-free survival rate in GIST patients. Results of multivariate analysis showed that the year of initial diagnosis, primary site, tumor maximum diameter, mitotic image, risk classification of NIH, R 0 resection, genetic testing and postoperative adjuvant therapy were independent factors influencing recurrence-free survival rate in GIST patients with initial surgical resection ( hazard ratio=0.58, 0.61, 2.00, 1.71, 5.81, 2.56, 0.65, 0.38, 95% confidence interval as 0.39-0.85, 0.45-0.83, 1.46-2.74, 1.24-2.35, 3.16-10.69, 1.63-4.02, 0.46-0.94, 0.25-0.56, P<0.05). Conclusions:GIST with initial surgical resection is common located in stomach, with high positive rate in CD117 and Dog-1. The number of people undergoing genetic testing and targeted therapy for GIST is increasing year by year. There are significant differ-ences in clinicopathological characteristics between GIST with non-gastric origin and gastric origin. The year of initial diagnosis, primary site, tumor maximum diameter, mitotic image, risk classifica-tion of NIH, R 0 resection, genetic testing and postoperative adjuvant therapy are independent factors influencing recurrence-free survival rate in GIST patients with initial surgical resection.

Inducing durable and effective immunity against severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) via vaccination is essential to combat the current pandemic of coronavirus disease 2019 (COVID-19). It has been noticed that the strength of anti-COVID-19 vaccination-induced immunity fades over time, which calls for an additional vaccination regime, as known as booster immunization, to restore immunity among previously vaccinated populations. Here we report a pilot open-label trial of a third dose of BBIBP-CorV, an inactivated SARS-CoV-2 vaccine (Vero cell), on 136 participants aged between 18 to 63 years. Safety and immunogenicity in terms of neutralizing antibody titers and cytokine/chemokine responses were analyzed as the main endpoint until day 28. While systemic reactogenicity was either absent or mild, SARS-CoV-2-specific neutralizing antibody titers rapidly arose in all participants within 4 weeks, surpassing the peak antibody titers elicited by the initial two-dose immunization regime. Broad increases of cellular immunity-associated cytokines and chemokines were also detected in the majority of participants after the third vaccination. Furthermore, in an exploratory study, a newly developed recombinant protein vaccine, NVSI-06-08 (CHO Cells), was found to be safe and even more effective than BBIBP-CorV in eliciting humoral immune responses in BBIBP-CorV-primed individuals. Together, these results indicate that a third immunization schedule with either homologous or heterologous vaccine showed favorable safety profiles and restored potent SARS-CoV-2-specific immunity, providing support for further trials of booster vaccination in larger populations.
Adolescent ; Adult ; Antibodies, Neutralizing ; Antibodies, Viral ; COVID-19/prevention & control* ; COVID-19 Vaccines/adverse effects* ; China ; Humans ; Immunogenicity, Vaccine ; Middle Aged ; SARS-CoV-2 ; Vaccination ; Young Adult

Objective: The antibacterial properties and bonding strength of 3M orthodontic adhesive resin modified by chlorhexidine acetate (CHA) composite mesoporous silica were investigated. Methods: CHA with different mass fractions was encapsulated in mesoporous silica nanoparticles (MSNs) (denoted CHA@MSNs). Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterize the samples. The 3M Z350XT flow resin was divided into 4 groups: group A: 3M+CHA@MSNs (0%); group B: 3M+CHA@MSNs (3%); group C: 3M+CHA@MSNs (5%); and group D: 3M+CHA@MSNs (6.4%), with mass scores of 0%, 3%, 5%, and 6.4%, respectively. The shear strength of the modified adhesive was tested by a universal electronic material testing machine, the adhesive residue was observed by a 10 × magnifying glass, and the adhesive Remnant index (ARI) was calculated. The four groups of modified adhesives were cultured with Streptococcus mutans. The OD540 value of the bacterial solution was measured by a spectrophotometer, and the amount of plaque attachment was observed by scanning electron microscopy to evaluate the antibacterial performance of the adhesives. Results: Infrared spectroscopic analysis of CHA@MSNs showed that CHA was successfully loaded onto MSNs. Under scanning electron microscopy, it could be seen that, after Cha was combined with MSNs, the structure of MSNs changed, as the boundary was fuzzy and aggregated into a layered structure. A comparison of shear strength revealed a statistically significant difference between the groups containing CHA@MSNs and the groups without CHA@MSNs (P<0.05). The value of the shear strength in group D decreased the most, while there was no statistically significant difference between group B and group C (P > 0.05). There was no statistical significance across all groups (P > 0.05), suggesting that the addition of CHA@MSNs had little effect on the bracket shedding. The OD540 value of bacterial fluid indicated that the difference among groups A, B and C was statistically significant (P < 0.05), and the antibacterial effect of group C was the best; there was no statistically significant difference between group C and group D (P > 0.05). Conclusions Therefore, adding 5% CHA@MSN antibacterial agent significantly improved the antibacterial effect and did not affect the bond strength.

Objective:To investigate the clinical efficacy of radical proximal gastrectomy with esophagogastrostomy and double-tract anastomosis for upper gastric cancer.Methods:The retrospective cohort study was conducted. The clinicopathological data of 172 patients who underwent radical proximal gastrectomy for upper gastric cancer in Tianjin Medical University Cancer Institute and Hospital from January 2018 to December 2020 were collected. There were 147 males and 25 females, aged from 25 to 81 years, with a median age of 62 years. All the 172 patients underwent digestive reconstruction. Of the 172 patients, 83 cases undergoing esophagogastrostomy were allocated into esophagogastrostomy group, 89 cases undergoing double-tract anastomosis were allocated into double-tract anastomosis group. Patients were performed radical proximal gastrectomy combined with D 1+ lymph node dissection by attending surgeons from department of gastric cancer. The operator decided to adopt esophagogastrostomy or double-tract anastomosis for digestive reconstruction. Observation indicators: (1) surgical situations; (2) follow-up. Follow-up using outpatient examination, telephone interview, and online APP was conducted at postoperative 1 month, once three months within postoperative 2 years, and once six months within postoperative 2-5 years. The questionnaires of reflux esophagitis, gastroscopy and upper gastrointestinal angio-graphy were conducted to evaluate gastroesophageal reflux and anastomotic stenosis up to February 1, 2021. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the t test. Measurement data with skewed distribution were represented as M (range), and comparison between groups was analyzed using the Mann-Whitney U test. Comparison of ordinal data was analyzed using the non-parameter rank sum test. Count data were represented as absolute numbers, and comparison between groups was analyzed using the chi-square test. Results:(1) Surgical situations: cases with open, laparoscopic or Da Vinci robotic surgery (surgical method), the number of metastatic lymph node, duration of postoperative hospital stay were 74, 9, 0, 2(range, 0-15), (12±4)days for the esophagogastrostomy group, versus 65, 15, 9, 3(range, 0-28), (11±3)days for the double-tract anastomosis group, respectively, showing significant differences in the above indicators between the two groups ( χ2=10.887, Z=-1.058, t=3.284, P<0.05). (2) Follow-up: 172 patients were followed up for 2-38 months, with a median follow-up time of 13 months. Cases with gastroesophageal reflux and anastomotic stenosis were 58 and 10 for the esophagogastrostomy group, versus 14 and 1 for the double-tract anastomosis group, respectively, showing significant differences in the above indicators between the two groups ( χ2=51.743, 7.219, P<0.05). Conclusions:For upper gastric cancer patients undergoing proximal radical gastrectomy, double-tract anastomosis is more suitable for Siewert type Ⅱ adenocarcinoma of esophagogastric junction in large curvature or lower located tumor. Compared with esophago-gastrostomy, double-tract anastomosis has lower incidence of postoperative gastroesophageal reflux and anastomotic stenosis, without increasing complications.

Gastrectomy with D2 lymph node dissection has become the global standard procedure for locally advanced gastric cancer. Based on the evidence of the clinic trials, postadjuvant chemotherapy after D2 gastrectomy is the current standard strategy. Neoadjuvant chemotherapy can increase the R0 resection rate, but the consensus has not been reached. These trials could lead to new evidence for improved treatment of gastric cancer in the near future. This review will summarize recent evidence on the benefits of for locally advanced gastric cancer.

Objective:To identify the epidemic clones of MRSA isolates at a hospital in shanghai.Methods:A total of 72 MRSA isolates have been isolated from a second grade hospital between 2017 and 2018, including 32 CA-MRSA isolates, 13 HA-MRSA isolates and 26 MRSA isolates from environment. In this study, MLST and PFGE typing methods were used to analyze the molecular epidemiology of the MRSA isolates.Results:A total of 72 MRSA isolates have been obtained including 46 isolates from clinical specimens, 26 isolates from environments. The 46 MRSA isolates from clinical specimens consisted of 33 CA-MRSA (community-acquired MRSA) and 13 HA-MRSA (hospital-acquired MRSA). Furthermore, these patients infected with MRSA isolates were mostly distributed in the department of geriatrics (34.8%, 16/46), internal medicine (26.1%, 12/46) and surgery (26.1%, 12/46). MLST typing results showed that ST764 was predominant in isolates from both clinical specimens and hospital environments. Furthermore, PFGE typing results showed that most ST764 MRSA had high homolog (>90%).Conclusion:ST764 MRSA isolates might spread in community, hospital and environments. Therefore, continuous monitoring of MRSA and its variation may be useful in understanding the involvement of epidemic clone, and in searching new strategies to control MRSA infection.

Objective:To identify the epidemic clones of MRSA isolates at a hospital in shanghai.Methods:A total of 72 MRSA isolates have been isolated from a second grade hospital between 2017 and 2018, including 32 CA-MRSA isolates, 13 HA-MRSA isolates and 26 MRSA isolates from environment. In this study, MLST and PFGE typing methods were used to analyze the molecular epidemiology of the MRSA isolates.Results:A total of 72 MRSA isolates have been obtained including 46 isolates from clinical specimens, 26 isolates from environments. The 46 MRSA isolates from clinical specimens consisted of 33 CA-MRSA (community-acquired MRSA) and 13 HA-MRSA (hospital-acquired MRSA). Furthermore, these patients infected with MRSA isolates were mostly distributed in the department of geriatrics (34.8%, 16/46), internal medicine (26.1%, 12/46) and surgery (26.1%, 12/46). MLST typing results showed that ST764 was predominant in isolates from both clinical specimens and hospital environments. Furthermore, PFGE typing results showed that most ST764 MRSA had high homolog (>90%).Conclusion:ST764 MRSA isolates might spread in community, hospital and environments. Therefore, continuous monitoring of MRSA and its variation may be useful in understanding the involvement of epidemic clone, and in searching new strategies to control MRSA infection.

Objective: To evaluate the impact of perineural invasion (PNI) on the overall survival (OS) of patients with gastric cancer. Methods: A total of 1,007 patients with gastric cancer who underwent curative resection between January 2011 and December 2012 at the Cancer Institute and Hospital of Tianjin Medical University were enrolled. All the patients were categorized into the following two groups according to the status of PNI: positive group, presence of PNI; and negative group, absence of PNI. Potential prognostic factors and clinical pathological variables correlated with the presence of PNI were analyzed. Results: One hundred and twenty (11.9%) patients had PNI. Multivariate analysis revealed that histology, depth of invasion, and lymphovascular invasion were indepen-dently associated with the presence of PNI. Univariate survival analysis revealed that age, tumor location, Borrmann type, tumor size, curability, TNM stage, type of gastrectomy, tumor deposit, lymphovascular invasion, PNI, preoperative CA19-9 levels, and CEA levels were significant prognostic factors. Gastric cancer patients with PNI had a significantly lower 5-year OS rate than those without PNI (5-year OS: 38.3% versus 66.6%, P<0.001). In the multivariate analysis, age, Borrmann typeⅣ, TNM stage, curability, tumor deposit, and PNI were independent prognostic factors for this population cohort. The strata analysis revealed that PNI merely had a significant im-pact on OS in patients at stagesⅠ,Ⅱ, andⅢa. Conclusions: PNI is an independent prognostic factor in patients with gastric cancer and can be used as a prognostic indicator for gastric cancer patients at stagesⅠ,Ⅱ, andⅢa.

Objective: To explore the clinical safety and feasibility of enterostomy using running suture of dermis and seromuscular layer in laparoscopic-assisted radical resection for rectal carcinoma. Methods: From May 1, 2017 to May 1, 2018, 46 patients who underwent laparoscopic-assisted radical resection for rectal carcinoma with enterostomy using running suture of dermis and seromuscular layer in Cancer Hospital, Chinese Academy of Medical Sciences were retrospectively enrolled in this study. Data regarding clinicopathologic characteristics, operation and postoperative outcomes, stoma-related complications and functions of stoma were collected and analyzed. Results: All of the 46 patients successfully underwent this operation. Among them, 30 patients underwent laparoscopic-assisted abdominoperineal resection for rectal cancer with sigmoidostomy and 16 patients underwent laparoscopic-assisted low anterior resection for rectal cancer with loop ileostomy. The mean operation time was 115.3 minutes and intraoperative blood loss was 86.1 ml. The mean time for enterostomy was 14.1 minutes. The average time to flatus, time to fluid diet intake and length of hospital stay were 1.8 days, 2.9 days and 6.5 days, respectively. During the follow-up period, three patients suffered from stomal edema, two patients suffered from parastomal hernia, and two patients suffered from skin inflammation surrounding stoma. None of re-operation related stoma and severe mobility such as stomal stenosis, stomal necrosis, stomal prolapse, stomal retraction and stomal mucocutaneous separation occurred. Thirty-five patients recovered with satisfactory stomal function, two with middle function and one with poor function. Conclusion Enterostomy using running suture of dermis and seromuscular layer in laparoscopic-assisted radical resection for rectal carcinoma is a safe and feasible procedure with a satisfactory short-term effect.