[Bowel preparation before colorectal surgery]

High quality bowel preparation is a necessary part of preoperative preparation for colorectal surgery and one of the keys to the success of surgery, which directly affects the quality of intraoperative procedures and postoperative recovery of patients. Conventional intestinal preparation mainly includes three aspects: preoperative dietary control, intestinal cleansing and prophylactic use of antibiotics. With the development of evidence-based medicine, the concepts and methods of bowel preparation have also changed. Long fasting is no longer advocated before surgery, and the traditional mechanical bowel preparation are also challenged. This article summarizes the application and research progress of different intestinal preparation methods before colorectal surgery, aiming to provide reference for clinical work of colorectal surgeons.

[Long-term outcome of patients with rectal cancer who achieve complete or near complete clinical responses after neoadjuvant therapy: a multicenter registry study of data from the Chinese Watch and Wait Database]

Objective: To report the long-term outcomes of Chinese rectal cancer patients after adopting a Watch and Wait (W&W) strategy following neoadjuvant therapy (NAT). Methods: This multicenter, cross-sectional study was based on real-world data. The study cohort comprised rectal cancer patients who had achieved complete or near complete clinical responses (cCRs, near-cCRs) after NAT and were thereafter managed by a W&W approach, as well as a few patients who had achieved good responses after NAT and had then undergone local excision for confirmation of pathological complete response. All participants had been followed up for ≥2 years. Patients with distant metastases at baseline or who opted for observation while living with the tumor were excluded. Data of eligible patients were retrospectively collected from the Chinese Wait-and-Watch Data Collaboration Group database. These included baseline characteristics, type of NAT, pre-treatment imaging results, evaluation of post-NAT efficacy, salvage measures, and treatment outcomes. We herein report the long-term outcomes of Chinese rectal cancer patients after NAT and W&W and the differences between the cCR and near-cCR groups. Results: Clinical data of 318 rectal cancer patients who had undergone W&W for over 2 years and been followed up were collected from eight medical centers (Peking University Cancer Hospital, Fudan University Shanghai Cancer Center, Sun Yat-sen University Cancer Center, Shanghai Changhai Hospital, Peking Union Medical College Hospital, Liaoning Cancer Hospital, the First Hospital of Jilin University, and Yunnan Cancer Hospital.) The participants comprised 221 men (69.4%) and 107 women (30.6%) of median age 60 (26-86) years. The median distance between tumor and anal verge was 3.4 (0-10.4) cm. Of these patients, 291 and 27 had achieved cCR or near-cCR, respectively, after NAT. The median duration of follow-up was 48.4 (10.2-110.3) months. The 5-year cumulative overall survival rate was 92.4% (95%CI: 86.8%-95.7%), 5-year cumulative disease-specific survival (CSS) rate 96.6% (95%CI: 92.2%-98.5%), 5-year cumulative organ-preserving disease-free survival rate 86.6% (95%CI: 81.0%-90.7%), and 5-year organ preservation rate 85.3% (95%CI: 80.3%-89.1%). The overall 5-year local recurrence and distant metastasis rates were 18.5% (95%CI: 14.9%-20.8%) and 8.2% (95%CI: 5.4%-12.5%), respectively. Most local recurrences (82.1%, 46/56) occurred within 2 years, and 91.0% (51/56) occurred within 3 years, the median time to recurrence being 11.7 (2.5-66.6) months. Most (91.1%, 51/56) local recurrences occurred within the intestinal lumen. Distant metastases developed in 23 patients; 60.9% (14/23) occurred within 2 years and 73.9% (17/23) within 3 years, the median time to distant metastasis being 21.9 (2.6-90.3) months. Common sites included lung (15/23, 65.2%), liver (6/23, 26.1%), and bone (7/23, 30.4%) The metastases involved single organs in 17 patients and multiple organs in six. There were no significant differences in overall, cumulative disease-specific, or organ-preserving disease-free survival or rate of metastases between the two groups (all P>0.05). The 5-year local recurrence rate was higher in the near-cCR than in the cCR group (41.6% vs. 16.4%, P<0.01), with a lower organ preservation rate (69.2% vs. 88.0%, P<0.001). The success rates of salvage after local recurrence and distant metastasis were 82.1% (46/56) and 13.0% (3/23), respectively. Conclusion: Rectal cancer patients who achieve cCR or near-cCR after NAT and undergo W&W have favorable oncological outcomes and a high rate of organ preservation. Local recurrence and distant metastasis during W&W follow certain patterns, with a relatively high salvage rate for local recurrence. Our findings highlight the importance of close follow-up and timely intervention during the W&W process.

Claudin-10 Decrease in the Submandibular Gland Contributes to Xerostomia

Tight junction proteins play a crucial role in paracellular transport in salivary gland epithelia. It is clear that severe xerostomia in patients with HELIX syndrome is caused by mutations in the claudin-10 gene. However, little is known about the expression pattern and role of claudin-10 in saliva secretion in physical and disease conditions. In the present study, we found that only claudin-10b transcript was expressed in human and mouse submandibular gland (SMG) tissues, and claudin-10 protein was dominantly distributed at the apicolateral membranes of acini in human, rat, and mouse SMGs. Overexpression of claudin-10 significantly reduced transepithelial electrical resistance and increased paracellular transport of dextran and Na+ in SMG-C6 cells. In C57BL/6 mice, pilocarpine stimulation promoted secretion and cation concentration in saliva in a dose-dependent increase. Assembly of claudin-10 to the most apicolateral portions in acini of SMGs was observed in the lower pilocarpine (1 mg/kg)-treated group, and this phenomenon was much obvious in the higher pilocarpine (10 mg/kg)-treated group. Furthermore, 7-, 14-, and 21-wk-old nonobese diabetic (NOD) and BALB/c mice were used to mimic the progression of hyposalivation in Sjögren syndrome. Intensity of claudin-10 protein was obviously lower in SMGs of 14- and 21-wk-old NOD mice compared with that of age-matched BALB/c mice. In the cultured mouse SMG tissues, interferon-γ (IFN-γ) downregulated claudin-10 expression. In claudin-10-overexpressed SMG-C6 cells, paracellular permeability was decreased. Furthermore, IFN-γ stimulation increased p-STAT1 level, whereas pretreatment with JAK/STAT1 antagonist significantly alleviated the IFN-γ-induced claudin-10 downregulation. These results indicate that claudin-10 functions as a pore-forming component in acinar epithelia of SMGs, assembly of claudin-10 is required for saliva secretion, and downregulation of claudin-10 induces hyposecretion. These findings may provide new clues to novel therapeutic targets on hyposalivation.

Ru-Based Organometallic Agents Bearing Phenyl Hydroxide: Synthesis and Antibacterial Mechanism Study against Staphylococcus aureus

The development of antimicrobial agents with novel model of actions is a promising strategy to combat multiple resistant bacteria. Here, three ruthenium-based complexes, which acted as potential antimicrobial agents, were synthesized and characterized. Importantly, three complexes all showed strong bactericidal potency against Staphylococcus aureus. In particular, the most active one has a MIC of 6.25 μg/mL. Mechanistic studies indicated that ruthenium complex killed S. aureus by releasing ROS and damaging the integrity of bacterial cell membrane. In addition, the most active complex not only could inhibit the biofilm formation and hemolytic toxin secretion of S. aureus, but also serve as a potential antimicrobial adjuvant as well, which showed synergistic effects with eight traditional antibiotics. Finally, both G. mellonella larva infection model and mouse skin infection model all demonstrated that ruthenium complex also showed significant efficacy against S. aureus in vivo. In summary, our study suggested that ruthenium-based complexes bearing a phenyl hydroxide are promising antimicrobial agents for combating S. aureus.

[The impact of extended waiting time on tumor regression after neoadjuvant chemoradiotherapy for locally advanced rectal cancer]

Objective: To investigate the influence of extending the waiting time on tumor regression after neoadjuvant chemoradiology (nCRT) in patients with locally advanced rectal cancer (LARC). Methods: Clinicopathological data from 728 LARC patients who completed nCRT treatment at the First Affiliated Hospital, Naval Medical University from January 2012 to December 2021 were collected for retrospective analysis. The primary research endpoint was the sustained complete response (SCR). There were 498 males and 230 females, with an age (M(IQR)) of 58 (15) years (range: 22 to 89 years). Logistic regression models were used to explore whether waiting time was an independent factor affecting SCR. Curve fitting was used to represent the relationship between the cumulative occurrence rate of SCR and the waiting time. The patients were divided into a conventional waiting time group (4 to <12 weeks, n=581) and an extended waiting time group (12 to<20 weeks, n=147). Comparisons regarding tumor regression, organ preservation, and surgical conditions between the two groups were made using the t test, Wilcoxon rank sum test, or χ2 test as appropriate. The Log-rank test was used to elucidate the survival discrepancies between the two groups. Results: The SCR rate of all patients was 21.6% (157/728). The waiting time was an independent influencing factor for SCR, with each additional day corresponding to an OR value of 1.010 (95%CI: 1.001 to 1.020, P=0.031). The cumulative rate of SCR occurrence gradually increased with the extension of waiting time, with the fastest increase between the 10th week. The SCR rate in the extended waiting time group was higher (27.9%(41/147) vs. 20.0%(116/581), χ2=3.901, P=0.048), and the organ preservation rate during the follow-up period was higher (21.1%(31/147) vs. 10.7%(62/581), χ2=10.510, P=0.001). The 3-year local recurrence/regrowth-free survival rates were 94.0% and 91.1%, the 3-year disease-free survival rates were 76.6% and 75.4%, and the 3-year overall survival rates were 95.6% and 92.2% for the conventional and extended waiting time groups, respectively, with no statistical differences in local recurrence/regrowth-free survival, disease-free survival and overall survival between the two groups (χ2=1.878, P=0.171; χ2=0.078, P=0.780; χ2=1.265, P=0.261). Conclusions: An extended waiting time is conducive to tumor regression, and extending the waiting time to 12 to <20 weeks after nCRT can improve the SCR rate and organ preservation rate, without increasing the difficulty of surgery or altering the oncological outcomes of patients.

The Role of Endothelial Barrier Function in the Fibrosis of Salivary Gland

In the salivary glands, fibrosis occurs in many pathological conditions. Endothelial tight junction (TJ)-based barrier function plays a vital role in maintaining the homeostasis of the salivary glands. However, whether endothelial barrier function is changed and involved in the pathogenesis of glandular fibrosis is unknown. Here, by using a mouse model in which the main excretory duct of the submandibular gland (SMG) was ligated to induce inflammation and fibrosis, endothelial barrier function and TJ protein expression and distribution were examined. Both 4-kDa and 70-kDa fluorescence-labeled dextrans permeated more in the 1-, 3-, and 7-d ligated SMGs. Meanwhile, the mRNA level of claudin-5 was increased with an obvious redistribution from apicolateral membranes to lateral membranes and cytoplasm in the fibrotic glands. Notably, the TJ sealer AT1001 significantly attenuated the disrupted endothelial barrier function and thereby ameliorated the glandular fibrosis. Cytokine array detection showed that monocyte chemoattractant protein-1 (MCP-1) was highly enriched in the 3-d ligated SMGs, and MCP-1 directly impaired barrier function, increased claudin-5 expression, induced the relocalization of claudin-5, and activated p-ERK1/2 in cultured human endothelial cells. Furthermore, the upregulation and disorganization of claudin-5 as well as the elevation of MCP-1 and p-ERK1/2 signaling were also confirmed in fibrotic SMGs from patients with chronic sialadenitis and immunoglobulin G4-related sialadenitis. Altogether, our findings revealed that disrupted endothelial barrier function contributed to the progression of glandular fibrosis, and targeting endothelial TJs might be a promising approach to alleviate salivary gland fibrosis-related diseases.

Analysis of synthetic electron cyclotron emission from the high field side of HL-2M tokamak plasmas

A synthetic electron cyclotron emission (ECE) diagnostic is used to interpret ECE signals from preset plasma equilibrium profiles, including magnetic field, electron density, and electron temperature. According to the simulation results, the electron temperature (T_e) profile covering the harmonic overlap region can be obtained by receiving ECE signals at the high field side (HFS) of the HL-2M plasma. The third harmonic ECE at the low field side (LFS) cannot pass through the second harmonic resonance layer at the HFS unless the optical thickness (τ) of the second harmonic becomes gray (τ ≤ 2). In addition, the impact of the relativistic frequency down-shift has been evaluated and corrected. The measurable range of the HFS ECE has been calculated by scanning different parameters (electron density, temperature, and magnetic field). Higher plasma parameters allow a wider radial range of electron temperature measurements. The minimum inner measurable position can reach R = 120 cm (r/a = -0.89) when the product of core temperature (T_e0) and density (n_e0) is greater than 35 × 10¹⁹ keV m^-3, which is extended by more than 30 cm inward compared with that of the LFS measurement. The HFS ECE will greatly improve the diagnostic ability of ECE systems on the HL-2M tokamak.

[A prospective cohort study on the clinical value of pelvic peritoneal reconstruction in laparoscopic anterior resection for middle and low rectal cancer]

Objective: To investigate the safety and efficacy of pelvic peritoneal reconstruction and its effect on anal function in laparoscopy-assisted anterior resection of low and middle rectal cancer. Methods: A prospective cohort study was conducted. Consecutive patients with low and middle rectal cancer who underwent laparoscopy-assisted transabdominal anterior resection at Naval Military Medical University Changhai Hospital from February 2020 to February 2021 were enrolled. Inclusion criteria: (1) the distance from tumor to the anal verge ≤10 cm; (2) laparoscopy-assisted transabdominal anterior resection of rectal cancer; (3) complete clinical data; (4) rectal adenocarcinoma diagnosed by postoperative pathology. Exclusion criteria: (1) emergency surgery; (2) patients with a history of anal dysfunction or anal surgery; (3) preoperative diagnosis of distant (liver, lung) metastasis; (4) intestinal obstruction; (5) conversion to open surgery for various reasons. The pelvic floor was reconstructed using SXMD1B405 (Stratafix helical PGA-PCL, Ethicon). The first needle was sutured from the left anterior wall of the neorectum to the right. Insertion of the needle was continued to suture the root of the sigmoid mesentery while the Hemo-lok was used to fix the suture. The second needle was started from the beginning of the first needle, after 3-4 needles, a drainage tube was inserted through the left lower abdominal trocar to the presacral space. Then, the left peritoneal incision of the descending colon was sutured, after which Hemo-lok fixation was performed. The operative time, perioperative complications, postoperative Wexner anal function score and low anterior resection syndrome (LARS) score were compared between the study group and the control group. Three to six months after the operation, pelvic MRI was performed to observe and compare the pelvic floor anatomical structure of the two groups. Results: A total of 230 patients were enrolled, including 58 who underwent pelvic floor peritoneum reconstruction as the study group and 172 who did not undergo pelvic floor peritoneum reconstruction as the control group. There were no significant differences in general data between the two groups (all P>0.05). The operation time of the study group was longer than that of control group [(177.5±33.0) minutes vs. (148.7±45.5) minutes, P<0.001]. There was no significant difference in the incidence of perioperative complications (including anastomotic leakage, anastomotic bleeding, postoperative pneumonia, urinary tract infection, deep vein thrombosis, and intestinal obstruction) between the two groups (all P>0.05). Eight cases had anastomotic leakage, of whom 2 cases (3.4%) in the study group were discharged after conservative treatment, 5 cases (2.9%) of other 6 cases (3.5%) in the control group were discharged after the secondary surgical treatment. The Wexner score and LARS score were 3.1±2.8 and 23.0 (16.0-28.0) in the study group, which were lower than those in the control group [4.7±3.4 and 27.0 (18.0-32.0)], and the differences were statistically significant (t=-3.018, P=0.003 and Z=-2.257, P=0.024). Severe LARS was 16.5% (7/45) in study group and 35.5% (50/141) in control group, and the difference was no significant differences (Z=4.373, P=0.373). Pelvic MRI examination 3 to 6 months after surgery showed that the incidence of intestinal accumulation in the pelvic floor was 9.1% (3/33) in study group and 46.4% (64/138) in control group (χ(2)=15.537, P<0.001). Conclusion: Pelvic peritoneal reconstruction using stratafix in laparoscopic anterior resection of middle and low rectal cancer is safe and feasible, which may reduce the probability of the secondary operation in patients with anastomotic leakage and significantly improve postoperative anal function.

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

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

[Twelve-week of sofosbuvir/velpatasvir therapeutic regimen for chronic hepatitis C patients in northwest region of China: a real-world multicenter clinical study]

Objective: To study the real-world outcome of China FDA-approved Sofosbuvir (SOF)/Velpatasvir (VEL) in Northwest China. Methods: In this multicenter, prospective, real-world cohort study, we recruited patients from 10 sites from Northwest China, who were chronically infected with HCV GTs 1-6 from 06/2018 to 09/2019. Patients received SOF (400mg)/VEL (100mg) for 12 weeks, and with ribavirin 900-1200 mg for GT3 cirrhosis and for any genotype decompensated cirrhosis. The primary endpoint was sustained virological response at 12-weeks post-treatment (SVR12) and safety. The secondary endpoint was the change of liver function after the achievement of SVR12. Results: Totally, 143 patients were enrolled in the study, four patients were lost to follow-up and one died during the follow-up, 138 patients were included in per-protocol analysis. Of the 138 patients, the mean age 53 years, 53.6% male, 94.2% Han nationality, 53.6% liver cirrhosis, 10.1% HBsAg(+), 6.5% renal dysfunction, 5.1% treatment-experienced, and 16.7% patients received ribavirin treatment. The genotype distribution was as follows: 35.5% GT1, 42.8% GT2, 15.9% GT3, and 5.8% un-typed. The SVR12 rate was 96.5% (138/143, 95%CI: 93.5%-99.6%) for intention-to-treat analysis, and in per-protocol analysis, all 138 patients obtained SVR12 (100%). Compared with baseline, the serum total bilirubin, ALT and AFP levels decreased (all P < 0.05), as well as increased ALB and platelet count (all P < 0.001) at post-treatment 12-weeks. Overall adverse events (AEs) rate is 29.0%, and the most common AEs were anemia (14.5%) and fatigue (8.0%). Severe side effects (edema and fatigue) occurred in 2 patients, one of whom needed a short-term interruption of treatment due to fatigue. Conclusion: In this real-world cohort study, 12-week SOF/VEL regimen with or without ribavirin achieved high SVR12 rates (96.5%-100% overall) with excellent safety profile among patients with HCV GT1/2/3 infection including patients with GT3 and cirrhosis, and led to improvement of liver function.

[The effect of visualized saphenous nerve block through minimally invasive far medial-subvastus approach on the analgesia after total knee arthroplasty]

Objective: To report a method of visualized saphenous nerve block (VSNB) through minimally invasive far medial-subvastus approach distal to the adductor canal in total knee arthroplasty (TKA), and investigate the effect of VSNB in this way on postoperative pain relief. Methods: A total of 100 patients with knee osteoarthritis were prospectively included from June 2018 to October 2019, 29 males and 71 females, aged 50-87(70±8) years. All patients undergoing TKA through minimally invasive far medial-subvastus approach were randomized to visualized saphenous nerve block combined with periarticular infiltration analgesia group (Group VSNB+PIA) or only periarticular infiltration analgesia group (Group PIA),50 cases in each group. The visual analogue scale (VAS) was used to evaluate the pain degree of patients. Furthermore, the scores of VAS in resting and active state at 4, 8, 12, 24, 48, 72 hours after operation and the proportion of patients receiving parecoxib within 72 hours after operation were compared between the two groups. Results: There was statistically significant difference between the two groups in terms of VAS scores in resting state after surgery(F=15.295,P<0.05).The postoperative VAS scores of Group VSNB+PIA at 4, 8, 12, 24 hours at resting state were 1.3±0.8, 1.4±0.7, 1.7±0.8, 3.1±0.8 respectively, which were all significantly lower than those of Group PIA (1.6±0.9, 1.8±0.8, 2.3±0.9, 3.6±0.8) (P<0.05). The overall difference in terms of VAS scores at active state after surgery was statistically significant between the two groups(F=18.532, P<0.05). The postoperative VAS scores of Group VSNB+PIA at 4, 8, 12, 24 hours at active state were 2.0±0.8, 2.2±0.7, 2.7±0.6, 3.7±0.7 respectively, which were all significantly lower than those of Group PIA (2.3±0.8, 2.7±0.7, 3.3±0.8, 4.4±0.7)(P<0.05). Fourteen percent of patients (7/50) in VSNB+PIA group accepted parecoxib within 72 hours after surgery, which was significantly lower than that in PIA group (34%, 17/50) (P<0.05). Conclusions: It is easy to expose the saphenous nerve beyond the adductor canal through minimally invasive far medial-subvastus approach. The Combination therapy of VSNB+PIA is more effective than the simple per-articular infiltration analgesia in providing pain relief after total knee arthroplasty.

Retrospective study of the functional and oncological outcomes of conformal sphincter preservation operation in the treatment of very low rectal cancer

BACKGROUND

Conformal sphincter preservation operation (CSPO) is a new surgical procedure for very low rectal cancers (within 4-5 cm from the anal verge). CSPO preserves more of the dentate line and distal rectal wall and also avoids injuring nerves in the intersphincteric space, resulting in satisfactory anal function after resection. The aim of this study was to analyze the short-term surgical results and long-term oncological and functional outcomes of CSPO.

METHODS

Consecutive patients with very low rectal cancer, who had CSPO between January 2011 and October 2018 at Changhai Hospital, Shanghai were included. Patient demographics, clinicopathological features, oncological outcomes and anal function were analyzed.

RESULTS

A total of 102 patients (67 men) with a mean age of 56.9 ± 10.8 years were included. The median distance of the tumor from the anal verge was 3 (IQR, 3-4) cm. Thirty-five patients received neoadjuvant chemoradiation (nCRT). The median distal resection margin (DRM) was 0.5 (IQR, 0.3-0.8) cm. One patient had a positive DRM. All circumferential margins were negative. There was no perioperative mortality. The postoperative complication rate was 19.6%. The median duration of follow-up was 28 (IQR, 12-45.5) months. The local recurrence rate was 2% and distant metastasis rate was 10.8%. The 3-year overall survival and disease-free survival rates were 100% and 83.9%, respectively. The mean Wexner incontinence and low anterior resection syndrome scores 12 months after ileostomy reversal were 5.9 ± 4.3, and 29.2 ± 6.9, respectively.

CONCLUSIONS

For patients with very low rectal cancers, fecal continence can be preserved with CSPO without compromising oncological results.

[Inflammation grading and sialoendoscopic treatment of 131I radioiodine-induced sialadenitis]

OBJECTIVE

To investigate the inflammation grading of ¹³¹I radioiodine-induced sialadenitis based upon sialoendoscopic and sialographic appearances, and to evaluate the results of sialoendoscopic intervention.

METHODS

The patients diagnosed with ¹³¹I radioiodine-induced sialadenitis and underwent sialoendoscopic exploration and intervention procedures in Peking University Hospital of Stomatology from Nov. 2012 to Oct. 2018 were included in this study. The appearances of sialogaphy and sialoendoscopy were analyzed and classified. The treatment options included irrigation with saline and dexamethasone and mechanical dilatation by sialoendoscope. The patients were followed up after treatment.

RESULTS

Forty-two patients with ¹³¹I radioiodine-induced sialadenitis were included. There were 5 males and 37 females, with a male-to-female ratio of 1 ∶7.4. Symptoms included recurrent swelling and pain in the parotid glands, and dry mouth. Sialography showed stenosis in the main duct,and in some cases nonvisua-lization of the branches. Sialoendoscopy showed narrowing of the main duct, and the branch duct atresia was seen. The appearances of sialogaphy and sialoendoscopy were analyzed and classified into 3 groups: (1) Mild inflammation: stenosis and ectasia occurred in the main duct, whereas the 0.9 mm sialoendoscope could pass through easily. (2) Moderate inflammation: one point of severe stricture could be seen in the main duct where 0.9 mm sialoendoscope could not be passed through. (3) Severe inflammation: two points or more of severe strictures or diffused strictures occurred in the main duct. Thirty-three patients with 65 affected glands were examined by both sialography and sialoendoscopy. Eight glands were classified as mild inflammation, 23 glands moderate inflammation, and 34 glands severe inflammation. The duration of follow-up ranged from 3-72 months. The clinical results were evaluated as good in 22 glands, fair in 22 glands, and poor in 19 glands, with an overall effective rate of 69.8% (44/63).

CONCLUSION

The clinical, sialographic and sialoendoscopic appearances of ¹³¹I radioiodine-induced sialadenitis showed their characteristics. We proposed an inflammation grading standard for the ¹³¹I radioiodine-induced sialadenitis based on the appearances of sialography and sialoendoscopy. Sialoendoscopy can significantly alleviate the clinical symptoms, which is an effective therapy, and better for early lesions.

[Several suggestion of operation for colorectal cancer under the outbreak of Corona Virus Disease 19 in China]

Pneumonia caused by SARS-Cov-2 infection has been reported in Wuhan since December 2019, and spread rapidly across the country. The radical operation of colorectal cancer is confine operation. Patients with colorectal cancer should receive operation as soon as possible after elective operation is resumed in each hospital. SARS-Cov-2 virus can be transmitted by asymptomatic infectors, and it has been confirmed to be transmitted by droplets and contact. However, fecal-oral transmission and aerosol transmission have not been excluded. Based onLaparoscopic colorectal operation experiences, the author suggests that the surgery strategy for colorectal cancer patients under the COVID-19 situation. Recommending laparoscopy-assisted radical surgery for colorectal cancer patients. The aerosols need to be strictly managed during operation. NOSES and TaTME should be carried out with cautious during the epidemic period. Protective stoma should be carried out scientifically and reasonably, and the protection of operating room personnel should be strengthened.

Difference in the frequency of pouchitis between ulcerative colitis and familial adenomatous polyposis: is the explanation in peripouch fat?

AIM

Patients with ulcerative colitis (UC) have an unexplained higher incidence of pouchitis and a greater amount of peripouch fat compared with patients with familial adenomatous polyposis (FAP). The aims of this study were to compare the peripouch fat areas between patients with UC and patients with FAP, and to explore relationship between peripouch fat and pouchitis or chronic antibiotic-refractory pouchitis (CARP).

METHOD

Patients with an abdominal CT image from our prospectively maintained Pouch Database were included. Abdominal fat and peripouch fat were measured on CT images at different levels or planes. Comparisons of peripouch fat and CARP were performed before and after propensity score matching.

RESULTS

A total of 277 patients with UC and 40 patients with FAP were included. Compared with patients with FAP, patients with UC were found to have a higher incidence of pouchitis (58.5% vs 15.0%, P < 0.001) and CARP (24.5% vs 2.5%, P = 0.002) and a higher total peripouch fat area (P = 0.030) and mesenteric peripouch fat area (P = 0.022) at Level-3. Univariate and multivariate analyses showed that diagnosis (UC vs FAP) and peripouch fat areas at Level-3 and Level-5 were independent risk factors for CARP. With propensity score matching, 38 pairs of patients with UC and FAP were matched successfully. After matching, patients with UC were found to have higher total peripouch fat area and higher mesenteric peripouch fat area at Level-3, and a higher incidence of pouchitis (57.9% vs 13.2%, P < 0.001) and CARP (23.7% vs 2.6%, P = 0.007).

CONCLUSION

Our study demonstrates that patients with UC have more peripouch fat than those with FAP, which may explain the difference in the frequency of pouchitis and CARP between these groups of patients.

TNF-α Suppresses Autophagic Flux in Acinar Cells in IgG4-Related Sialadenitis

IgG4-related sialadenitis (IgG4-RS) is a newly recognized immune-mediated systemic fibroinflammatory disease that affects salivary glands and leads to hyposalivation. Tumor necrosis factor-α (TNF-α) is a critical proinflammatory cytokine involved in several salivary gland disorders, but its role and mechanism regarding acinar cell injury in IgG4-RS are unknown. Here, we found that TNF-α level was significantly increased in serum and submandibular gland (SMG) of patients and that serum TNF-α level was negatively correlated with saliva flow rate. Ultrastructural observations of IgG4-RS SMGs revealed accumulation of large autophagic vacuoles, as well as dense fibrous bundles, decreased secretory granules, widened intercellular spaces, swollen mitochondria, and expanded endoplasmic reticulum. Expression levels of LC3 and p62 were both increased in patients' SMGs. TNF-α treatment led to elevated levels of LC3II and p62 in both SMG-C6 cells and cultured human SMG tissues but did not further increase their levels when combined with bafilomycin A1 treatment. Moreover, transfection of Ad-mCherry-GFP-LC3B in SMG-C6 cells confirmed the suppression of autophagic flux after TNF-α treatment. Immunofluorescence imaging revealed that costaining of LC3 and the lysosomal marker LAMP2 was significantly decreased in patients, TNF-α-treated SMG-C6 cells, and cultured human SMGs, indicating a reduction in autophagosome-lysosome fusion. Furthermore, the ratio of pro/mature cathepsin D was elevated in vivo, ex vivo, and in vitro. TNF-α also appeared to induce abnormal acidification of lysosomes in acinar cells, as assessed by lysosomal pH and LysoTracker DND-26 fluorescence intensity. In addition, TNF-α treatment induced transcription factor EB (TFEB) redistribution in SMG-C6 cells, which was consistent with the changes observed in IgG4-RS patients. TNF-α increased the phosphorylation of extracellular signal-regulated kinase (ERK) 1/2, and inhibition of ERK1/2 by U0126 reversed TNF-α-induced TFEB redistribution, lysosomal dysfunction, and autophagic flux suppression. These findings suggest that TNF-α is a key cytokine related to acinar cell injury in IgG4-RS through ERK1/2-mediated autophagic flux suppression.

[Comparison of the secretory related molecules expression in stem cells from the pulp of human exfoliated deciduous teeth and dental pulp stem cells]

Objective: To compare the general biological characteristics and the expressions of proteins involved in secretion in stem cells from the pulp of human exfoliated deciduous teeth (SHED) and dental pulp stem cells (DPSC). Methods: SHED and DPSC were cultured and collected at passage 4 (P4) and P7. The submandibular gland epithelial and interstitial cells were cultured with tissue culture method. The cell morphology was observed using a phase contrast microscope. Flow cytometry was used to detect stem cell surface markers. Cell counting kit-8 (CCK-8) and IncuCyte ZOOM were used to evaluate cell proliferation. Quantitative real-time PCR (qPCR) was performed to examine the mRNA expressions of proteins involved in fluid and protein secretion. Results: P4 and P7 SHED and DPSC were spindle-shaped. There was no difference in cell morphology among the 4 group cells. P4 and P7 SHED and DPSC expressed CD29, CD44, CD73, and CD90, the mesenchymal stem cell markers, while, CD49f and CD117, the epithelium markers were undetected. There was no difference in cell proliferation among the 4 group cells. Compared with P4 SHED, the expressions of muscarinic cholinergic receptor 1 (MR1), MR3, aquaporin 5 (AQP5), β1-adrenoceptor (β1-AR), α-amylase, and mucin 5B in SHED were not different, while β2-AR expression was decreased (P<0.05). Compared with P4 DPSC, the expressions of MR3, β2-AR, and α-amylase in P7 DPSC were not different, while, the expressions of MR1, AQP5, β1-AR, and mucin 5B were decreased (P<0.05). Compared with primary cultured submandibular gland epithelial cells and gland tissues from a child, the expressions of proteins involved in secretion were all decreased. Compared with submandibular epithelial cells from adults, the expression of AQP5 in P4 DPSC was decreased (P<0.05), while other proteins were not different. The expressions of AQP5, β1-AR, α-amylase and mucin 5B in P7 DPSC were increased (P<0.05), while other proteins were not different. In P4 and P7 DPSC, all the protein expression levels were decreased, compared with those in submandibular gland tissues (P<0.01). Conclusions: Compared with DPSC, SHED have stable growth and the expressions of protein involved fluid and protein secretion are low. Based on its extensive sources and easy separation, SHED can be used as the ideal seed cell for salivary gland tissue engineering and the treatment of salivary gland hypofunction, and the P4 to P7 SHED can be used for experimental study.

[Research progress of salivary glands mucosa-associated lymphoid tissue lymphoma]

Salivary glands mucosa-associated lymphoid tissue lymphoma (SGML) is a distinct subtype of marginal zone B-cell type non-Hodgkin's lymphoma (NHL), which is commonly seen in middle aged females. SGML is usually associated with autoimmune diseases such as Sjögren's syndrome or with chronic infection such as hepatitis C virus (HCV) infection. Chromosomal abnormalities are frequently seen in SGML, which usually activate nuclear factor-κB molecular pathway to modulate cell survival and proliferation, resulting in lymphoma occurrence. SGML tends to arise from parotid gland, presenting frequently as a localized and indolent lesion, a long-term follow-up and biopsy are needed for accurate diagnosis. Surgery, radiotherapy and chemotherapy are usually effective disseminated diseases at multiple sites need combined treatment. SGML has a relatively better prognosis with a higher relapse rate than other types of NHLs, dissemination or higher degree of malignant transformation may occur. Thus, a long-term and close follow-up is essential for patients with SGML.

[Comorbidity in oral squamous cell carcinoma patients: an initial research in Beijing area]

Objective: To make a preliminery research of comobidity in oral squamous cell carcinoma (OSCC) patients who resides in Beijing area and investigate whether comorbidity affect the surviving rate independently. Compare the similarities and differences between Chinese and foreign OSCC patients. Methods: The medical records of 313 patients who undertaken operation in Peking University Stomatology School from January 2007 to Delember 2009 were retrospectively reviewed. Adult comorbidity evaluation-27 Chinese edition index was used to estimate the comorbidity severity. COX proportional hazards model was used to analyze whether the TNM stage, comobidity, age and gender affected 5-year survival rate. Results: TNM stage and comorbidity have a significant impact on survival rate, the postoperative survival rate decreased significantly with the increasing level of TNM staging and the complexity of comorbidity disease. In this study, the proportion of patients with none, mild, moderate and severe comorbidity diseases was 24%, 48%, 18% and 10%. The five-year survival rates of patients with moderate and severe comorbidity disease were 50% (29/58) and 13% (4/30) respectively. Conclusions: The comorbidity disease information can help assess the overall health of OSCC patients, and it is recommended to improve the clinical staging and overall evaluation of oral cancer patients with comorbidity disease information.

Pre-Injection of Small Interfering RNA (siRNA) Promotes c-Jun Gene Silencing and Decreases the Survival Rate of Axotomy-Injured Spinal Motoneurons in Adult Mice

Brachial plexus injury is a common clinical peripheral nerve trauma. A series of genes in motoneurons were activated in the corresponding segments of the spinal cord after brachial plexus roots axotomy. The spatial and temporal expression of these genes directly affects the speed of motoneuron axon regeneration and precise target organ reinnervation. In a previous study, we observed the overexpression of c-Jun in motoneurons of the spinal cord ventral horn after brachial plexus injury in rats. However, the relevance of c-Jun expression with respect to the fate of axotomy-induced branchial plexus injury in adult mice remains unknown. In the present study, we explored the function of c-Jun in motoneuron recovery after axotomy. We pre-injected small interfering RNA (siRNA) to knockdown c-Jun expression in mice and examined the effects of the overexpression of c-Jun in motoneurons after the axotomy of the brachial plexus in vivo. Axotomy induced c-Jun overexpression in the ventral horn motoneurons of adult mice from 3 to 14 days after injury. In addition, the pre-injection of siRNA transiently inhibited c-Jun expression and decreased the survival rate of axotomy-injured motoneurons. These findings indicate that the axotomy-induced overexpression of c-Jun plays an important role in the survival of ventral horn motoneurons in adult mice. In addition, the pre-injection of c-Jun siRNA through the brachial plexus stem effectively adjusts c-Jun gene expression at the ipsilateral side.

LAP+CD4+ T cells are elevated among the peripheral blood mononuclear cells and tumor tissue of patients with hepatocellular carcinoma

The purpose of the present study was to investigate the role of latency-associated peptide (LAP)⁺CD4⁺T cells in hepatocellular carcinoma (HCC) immunity. Flow cytometric analysis was performed to detect the proportion of LAP⁺CD4⁺ T cells among the peripheral blood mononuclear cells (PBMCs) of 30 HBV-infected HCC patients at the pre-operative and post-operative stages, as well as 30 hepatitis B virus (HBV)-infected volunteers as a control group. Furthermore, tumor tissues and peri-tumor tissues from 28 patients with HCC, as well as hepatic tissues from 28 HBV-infected patients with benign lesions were subjected to immunohistochemical analysis with double staining for LAP and CD4, and the average number of the LAP⁺CD4⁺T cells in each visual field was quantified. The results indicated that the proportion of LAP+CD4+ T cells in the PBMCs of patients with HCC was significantly higher than that in the control group (1.84±0.85 vs. 0.73±0.39%, P=0.019), while it was significantly reduced after the operation (1.07±0.35, P=0.021), but still slightly, if not significantly, higher compared with that in the control group (P=0.342). Furthermore, the number of LAP⁺CD4⁺ T cells per high-magnification microscopic field (magnification, ×400) in the HCC tissues was 11.25±3.00, which was significantly higher than that in the peri-cancer tissues (5.75±1.00) and that in the HBV-infected hepatic tissues around benign lesions (2.61±0.83). In peri-cancer tissues, LAP⁺CD4⁺ T cells were also significantly more abundant than in control tissues. Furthermore, in the HCC tissues, LAP⁺CD4⁺ T cells were present as clusters in the tumor stroma and closely associated with CD4⁺ T lymphocytes. By contrast, in the peri-cancer liver tissues and HBV-infected hepatic tissues around benign lesions, LAP⁺CD4⁺ T cells were sparsely distributed. LAP⁺CD4⁺ T cells have marked inhibitory effects, and in the peripheral blood and tumor tissues of patients with HCC, they have an important role in the suppression of anti-tumor immunity and in the immune evasion of tumor cells.

[Endoscopy-assisted sialodochoplasty for the treatment of severe sialoduct stenosis]

OBJECTIVE

To evaluate the effects of endoscopy-assisted sialodochoplasty for the treatment of severe sialoduct stenosis with concurrent megaducts.

METHODS

From Jul.2010 to Dec. 2016, 8 patients presenting with severe parotid duct stenosis and 3 patients with occlusion of the Wharton's duct underwent endoscopy-assisted sialodochoplasty.All these patients had concurrent severe ductal ectasiaand manifested a painful swelling of the involved salivary glands.The diameter of ectasia and length of stenosis of the sialoducts were measured preoperatively by sialography, computed tomography, or ultrasonography. The megaducts were opened transorally and sutured to the buccal or oral floor mucosa, therefore creating a neo-ostium. All the patients were followed up periodically after operation. The treatment effects were evaluated by clinical signs, sialogram and sialometry.

RESULTS

The length of the Stensen's duct stenosis was 5-12 mm, and the diameter of the concurrent ectasia was 8-16 mm. The length of the Wharton's duct stenosis was 10-20 mm, and the diameter of the concurrent ectasia was 6-8 mm.The neo-ostiums healed uneventfully 2 weeks after operation. The duration of the follow-up varied from 6 to 78 months (median: 24 months). Among the 8 patients with Stensen's duct stenosis, two experienced re-obliteration of the neo-ostium, but the buccal bulge and clinical symptoms disappeared; one reported recurrent clinical symptoms after initial alleviation, which could be controlled with self-massaging; the remaining 5 patients had satisfactory clinical results, i.e., disappearance of the obstruction symptoms and buccal bulge, patent ostium,clean saliva and improvement of the ductal ectasia on sialogram. Three patients with Wharton's duct occlusion were asymptomatic with clear saliva and patent ostium;two exhibited approximately normal appearance and one showed improvement of the sialogram.Sialometry was performed in 9 patients with patent neo-ostium of the involved glands,the resting saliva flow rate of the affected glands showed no differences compared with the normal side, and stimulated flow rate showed a significant increase, though less than the control side.The clinical results included good in 5 patients, fair in 4 patients, and poor in 2 patients, with a total effective rate of 82% (9/11).

CONCLUSION

Endoscopy-assisted sialodochoplasty appears to be effective and can be a viable option for patients presenting with severe sialoducts tenosis and concurrent ectasia.

[A 20-year study on microvascular autologous transplantation of submandibular gland for treatment of severe dry eye]

Severe dry eye is a refractory ophthalmologic disease. Our multidisciplinary research group treated severe dry eye by microvascular autologous transplantation of submandibular gland (SMG) during the past 20 years. The SMG, with its blood vessels and Wharton's duct, was harvested from the submandibular triangle and transferred to the temporal area. The blood vessels in the SMG were anastomosed with the temporal blood vessels using a microsurgical technique. Then, the distal end of Wharton's duct was sutured to form an opening in the upper lateral conjunctival fold. The tear was replaced by the secretion of the transplanted SMG to lubricate the ocular surface. In our study, the surgical techniques of blood vessel management were continuously modified to increase the survival rate of the transplanted SMG. A novel surgical modality of partial transplantation of SMG was established to prevent postoperative epiphora. A clinical study with the largest case number in the world was conducted and the effectiveness of transplantation of SMG for severe dry eye was fully confirmed. In order to resolve two main clinical problems including ductal obstruction resulted from low secretion rate during the latent period, and epiphora due to over secretion of the transplanted SMG in the later term of transplantation, the regulation of the secretion mechanism of the normal and transplanted SMG were investigated. New opinions on mechanisms of saliva secretion were provided. Based on the priniciple of translational medicine, the results of related basic research were applied in the clinic. The clinical guidelines for secretion regulation of transplanted SMG were established. A concept of chronic obstructive sialadenitis of transplanted SMG was provided and its diagnostic criteria, diagnostic technique of sialography, and therapeutic regimen were established. As a result, the surgical success rate was obviously elevated, the surgical complications were decreased, and life quality of the patients was greatly improved.

[Clinical analysis of cervical lymph node metastasis of cN0 maxillary malignant tumor]

OBJECTIVE

To investigate the cervical lymphatic metastasis rates of clinically negative neck lymph node (cN0) maxillary malignant tumors, to compare the cervical lymphatic metastasis rates of the various pathological types, and to provide the reference for the treatment of the neck of the patients with cN0 maxillary malignant tumor.

METHODS

The clinical data of 277 cases with cN0 maxillary malignant tumor, treated in the department of oral and maxillofacial surgery of Peking University School and Hospital of Stomatology from 1990 to 2010, were reviewed. The cervical lymph node metastasis and the related clinical information were recorded. The clinical information including histopathology type of the tumors, tumor grade, primary site and TNM staging, as well as other demographic and clinical data, were retrieved from the electronic medical record system (EMRS) of the hospital. The pathogenesis of cervical lymph node metastasis in maxillary malignant tumors of different histopathological types, and the factors related to lymph node metastasis of upper cervical malignancy were analyzed by SPSS 19.0 statistical software.

RESULTS

The overall cervical lymph node metastasis rate of the 277 patients with cN0 maxillary malignant tumor was 15.5% (43/277). Maxillary squamous cell carcinoma (SCC) had a strong cervical lymph node metastasis tendency and the rate was 33.0%. The overall metastatic rate of adenocarcinoma was 7.6% lower than that of SCC, and the occurrence of cervical lymph node metastasis time was relatively late, but the metastasis rate of highly malignant grade salivary gland carcinoma was significantly higher than that of intermediate and low grade carcinoma (P=0.037). The metastatic rates of some highly malignant cN0 salivary gland carcinomas including adenocarcinoma, not other specified, high-grade mucoepidermoid carcinoma (MEC), and salivary duct carcinoma were exceeded 15%, while the metastasis rates of adenoid cystic carcinoma and myoepithelial carcinoma were lower. The metastasis rate of the sarcomas was very low with the rate of 4.9%.

CONCLUSION

Selective neck dissection (SND) is recommended for cN0 maxillary SCC and feasible for some highly malignant cN0 salivary gland carcinomas including adenocarcinoma, not other specified, high-grade MEC, salivary duct carcinoma. The neck can be closely observed for the patients with maxillary sarcoma.