Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection is a new respiratory infectious disease.Patients with chronic kidney disease are at high risk of SARS-CoV-2 infection.Once they develop SARS-CoV-2 infection,the rate of progression to severe illness or even death is much higher than that of the general population.Nirmatrelvir/ritonavir significantly reduce the risk of severe illness and death in patients infected with SARS-CoV-2.In this paper,the dosing regimen and drug interaction of nirmatrelvir/ritonavir in patients with different stages of chronic kidney disease complicated with SARS-CoV-2 infection were reviewed to provide a reference for clinical rational medication for patients with chronic kidney disease.

Objective·To explore the efficacy and safety of compound amino acid capsules in the treatment of malnutrition and calcium and phosphorus metabolism disorders in maintenance hemodialysis patients.Methods·In this prospective,randomized,controlled,single-center study,forty maintenance hemodialysis patients from Renji Hospital,Shanghai Jiao Tong University School of Medicine were randomly divided into two groups,the treatment group(n=21)and the control group(n=19).The treatment group was given oral compound amino acid capsules on the basis of regular hemodialysis treatment,while the control group received no special nutritional intervention.Serum albumin,prealbumin,hemoglobin,ferritin,calcium,phosphorus,1,25-(OH)2-D3 and intact parathyroid hormone levels were analyzed every 3 months,and the incidence of adverse events including death,cardio-cerebrovascular accidents and vascular access failure was recorded.The total follow-up period was 9 months.Results·Serum albumin and prealbumin in the treatment group at 6-month and 9-month were significantly higher than the baseline parameters(albumin,t=3.574,5.599,both P<0.05;prealbumin,t/Z=-2.485,2.921,both P<0.05).Albumin in the control group increased at 9-month with a lower amplification compared to the treatment group(t=3.877,P=0.001),while the difference of prealbumin showed no statistical significance during follow-up.Hemoglobin and serum ferritin in the treatment group started to increase at 3-month(hemoglobin,t=2.192;ferritin,t=2.994;both P<0.05).Phosphorus in treatment group decreased at 3-month and 9-month(t/Z=-2.743,-2.103,both P<0.05),while phosphorus in the control group remained relatively stable during the first 6 months and increased at 9-month(Z=-2.178,P=0.029).Calcium and 1,25-(OH)2-D3 in the treatment group at 3-month and 6-month were significantly higher than the baseline parameters(calcium,t=4.581,4.922,both P=0.000;1,25-(OH)2-D3 t/Z=4.504,-2.374,both P<0.05),while the increase in blood calcium in the control group was significantly smaller than that in the treatment group during the same period.1,25-(OH)2-D3 in the control group showed no significant improvement.There was no significant difference in intact parathyroid hormone level,incidence of adverse events and other laboratory examination results between the two groups.Conclusion·Compound amino acid capsules can ameliorate the nutrition status and regulate calcium and phosphorus metabolism effectively and safely in maintenance hemodialysis patients.

Objective:To explore the isolation and culture methods of mouse parietal epithelial cells (PECs) of Bowman′s capsule, so as to provide a cell tool for further study.Methods:Mouse renal corpuscles were isolated by cell sieving combined with magnetic separation. After primary culture, identified parietal epithelial cells were induced to differentiate into podocytes. Immunofluorescence staining, real-time quantitative PCR and Western blotting were used to detect specific markers of parietal epithelial cells and podocytes.Results:Primary cultured PECs grew like paving stone and expressed Claudin-1 (PECs specific marker), CD133 (stem cell marker) and CD24 (stem cell marker), without the expression of tubular epithelial cell proteins, mesangial cell and podocyte specific proteins. Cultured to 6 generations in vitro, the PECs still expressed Claudin-1, CD133 and CD24. After incubated with differentiation medium, PECs were able to express podocyte markers WT-1 and Synaptopodin. Conclusion:The renal corpuscles are extracted by cell sieving combined with magnetic separation, and the mouse PECs successfully cultured in vitro can be induced to express podocytes′ markers.

Objective:To observe the clinical characteristics of esophageal reflux after total gastrectomy (ERATG), and to explore the mechanism of occurrence.Methods:Fourteen gastric cancer patients who underwent total gastrectomy were prospectively enrolled in this study. The postoperative symptoms were observed and recorded and 24 h MII-pH with pH monitoring was performed to investigate the characteristics of postoperative reflux.Results:After total gastrectomy patients were with different degrees of ERATG as heartburn, appetite loss, chest tightness and belching. The overall nature of ERATG is mainly weak acid, with a pH between 4 and 7. ERATG involved esophageal-jejunal anastomosis and a length of esophagus 7 cm above the anastomosis. Patients with typical reflux symptoms had a lower pH minimum in the upright position than those without typical symptoms[(4.76±0.71) vs.(5.68±0.37), t=2.866, P<0.05]. Patients with typical reflux symptoms had a higher frequency of reflux of mixed liquid and liquid-air reflux than those without typical symptoms[liquid(31.25±29.76) vs.(4.50±9.14), t=0.011, P<0.05; liquid-air(19.50±12.99) vs.(2.00±2.61), t=0.004, P<0.05]. Conclusion:ERATG is mainly a upward reflux of weakly acidic gas, with typical symptoms of heartburn, appetite loss, chest tightness and belching. Patients with typical symptoms usually have lower pH in the upright position.

Objective:To investigate the experience and results of the modified lateral prostate capsule sparing robot-assisted radical cystectomy-orthotopic ileal neobladder (LPCS-RARC-OIN).Methods:From December 2018 to November 2020, 19 patients received LPCS-RARC-OIN by a single surgeon in Sun Yat-sen Memorial Hospital, Sun Yat-sen University. LPCS-RARC-OIN was performed on male patients with high-risk non-muscle-invasive bladder cancer or muscle-invasive bladder cancer cT 2N 0M 0 without tumour in the bladder neck or urethra, and prostate cancer was ruled out by MRI and serum PSA<2.5ng/ml. The average age was 57.6 years, the average IIEF-5 score was 20.4. Separating the prostatic adenoma and the lateral prostate capsule from the base to the apex of the prostate, and retaining the lateral prostate surgical capsule or lateral prostate capsule about 1-2mm thickness. Patients were followed up and urinary function, sexual function and oncological outcomes were recorded. Results:All 19 operations were finished successfully. The average operation time was 279.9 (225-345) min and average estimated blood loss was 88.9 (30-200) ml. The average postoperative hospital stays was 15.8 (9 -23) days. The average lymph node yields was 23.3 (11-42). All surgical margins were negative and no incidental prostate cancer was found. 2 weeks, 1 month, 3 months and 6 months after catheter removal, the daytime and nighttime continence were 42.1% (8/19)and 36.8% (7/19), 63.2% (12/19)and 63.2% (12/19), 78.9% (15/19) and 73.7% (14/19), 94.7% (18/19) and 89.5% (17/19), respectively. 3 months and 6 months after operation, the average IIEF-5 score was 7.2 and 10.1 points respectively. The average follow-up was 10.6 months (5.4-26.1 months)and no recurrence or distant metastasis was found in this study.Conclusions:LPCS-RARC-OIN could improve the urinary and sexual function in selected patients. However, the long-term follow up is needed for functional and oncological outcomes.

Objective:To determine the diagnostic value of tumor markers in peritoneal lavage fluid from colorectal cancer patients for tumor peritoneal metastasis.Methods:A total of 227 colorectal cancer patients who undergoing surgical treatment were included. 300 ml of peritoneal lavage fluid was irrigated immediately upon laparotomy for traditional cytology (PLC) testing, 134 patients were tested for tumor marker of peritoneal lavage fluid (pTM). Univariate analysis was performed to determine the risk factors for peritoneal metastasis; pTM ROC curve was used to determine the best cutoff value; paired chi-square test was used to compare the difference between PLC and pTM detection.Results:The positive rate of PLC was 12.3% (28/227). Age>65, stage T3 + , lymph node metastasis, mucinous adenocarcinoma and increased serum CA125, CA19-9 are related to peritoneal metastasis; The best cutoff value of pTM for peritoneal metastasis : pCEA 17.095 ng/dl, sensitivity 58.3%, specificity 93.9%; pCA19-9 4.515 U/ml, sensitivity 83.3%, specificity 80.0%; pCA125 303.2 U/ml, sensitivity 58.3%, specificity 95.7%; pCA-724 3.01 U/ml, sensitivity 66.7%, specificity 95.7%; The best cutoff value of pTM for peritoneal micrometastasis: pCA19-9 3.43 U/ml, sensitivity 100%, specificity 72.2%. The positive rate of pCA19-9 was 29.85%, which was higher than that of PLC (χ 2=2.00, P<0.05). Conclusion:Peritoneal metastasis of colorectal cancer is related to tumor T stage, lymph node metastasis, tumor pathological type, and increased serum CA125 and CA19-9; pTM has diagnostic value for peritoneal metastasis of colorectal cancer.

Objective:To investigate the role of indocyanine green(ICG) fluorescence imaging in laparoscopic anterior resection for rectal cancer.Methods:A retrospective analysis was performed on 7 patients who had undergone laparoscopic anterior resection with the use of ICG fluorescence imaging at Peking University People′s Hospital between Oct 2018 and Mar 2019. The clinicopathological variables, surgical factors, short-term outcome and complications were analyzed.Results:The median operation time was 185 min. The median estimated blood loss was 50 ml. The median time from ICG injection to anastomotic perfusion was 45 s. One patient received extended proximal resection of bowel due to poor perfusion as suggested by ICG imaging. The median time to soft diet was 4 days, and the median hospital stay was 8 days. The median number of lymph nodes harvested was 16. There were no major complications in all these patients. No adverse events related to ICG were recorded.Conclusions:ICG fluorescence imaging was safe and effective in detecting insufficient blood supply around newly established bowel anastomsis, hence potentially reducing the anastomotic leakage rate.

Objective:To investigate the efficacy and prognosis of three surgical methods for presacral recurrent rectal cancer (PRRC).Methods:A retrospective cohort study was carried out. Case inclusion criteria: (1) primary rectal cancer without distant metastasis and undergoing radical surgery; (2) patients undergoing radical surgery after the diagnosis of PRRC; (3) complete inpatient, outpatient and follow-up data. Clinical data of 47 patients meeting the above criteria who underwent operation at the Department of Gastrointestinal Surgery, The Peking University People's Hospital from January 2008 to December 2017 were reviewed and analyzed retrospectively. Of the 47 patients, 31 were male and 16 were female; the mean age was 57 years old; 9 (19.1%) were low differentiation or signet ring cell carcinoma, 38 (80.9%) were medium differentiation; 19 (40.4%) received neoadjuvant therapy. According to operative procedure, 22 patients were in the abdominal/abdominoperineal resection group, 15 in the sacrectomy group and 10 in the abdominosacral resection group. The operative data, postoperative data and prognosis were compared among the three groups. Survival curve was conducted using the Kaplan-Meier method, and log-rank test was used to compare survival difference among three groups.Results:There were no significant differences in baseline data among three groups (all P>0.05). All the 47 patients completed the radical resection successfully. The mean operation time was (4.7±2.1) hours, the median intraoperative blood loss was 600 ml, and the median postoperative hospitalization time was 17 days. Fifteen cases (31.9%) had perioperative complications, of which 3 cases were grade III-IV. There was no perioperative death. The mean operative time was (7.4±1.6) hours in the abdominosacral resection group, (4.9±1.6) hours in the abdominal/abdominoperineal resection group, and (3.0±1.1) hours in the sacroectomy group, with a significant difference ( F=25.071, P<0.001). There were no significant differences in intraoperative blood loss, postoperative hospitalization days and perioperative complications among the three groups (all P>0.05). The median follow-up period of all the patients was 24 months, 12 cases (25.5%) developed postoperative dysfunction. The incidence of postoperative dysfunction in the abdominosacral resection group was 5/10, which was higher than 4/15 in the sacrectomy group and 3/22 (13.6%) in the abdominoperineal resection group with statistically significant difference (χ 2=9.307, P=0.010). The 1-year and 3-year overall survival rates were 86.1% and 40.2% respectively. The 1-year overall survival rates were 86.0%, 86.7% and 83.3%, and the 3-year overall survival rates were 33.2%, 40.0% and 62.5% in the abdominal/abdominoperineal resection group, sacrectomy group and abdominosacral resection group, respectively, whose difference was not statistically significant (χ 2=0.222, P=0.895). Conclusions:Abdominal/abdominoperineal resection, sacrectomy and abdominosacral resection are all effective for PRRC. Intraoperative function protection should be concerned for patients undergoing abdominosacral resection.

Objective:To investigate the clinicopathological features and prognostic factors in patients with presacral recurrent rectal cancer (PRRC).Methods:PRRC was defined as recurrence of rectal cancer after radical surgery involving posteriorly the presacral soft tissue, the sacrum/coccyx, and/or sacral nerve root. The diagnosis is confirmed with clinical symptoms (pain of pelvis/back/lower limb, bloody stools, increased frequency of defecation, and abnormal secretions), physical examination of perineal or pelvic masses, radiological findings, colonoscopy with histopathological biopsy, and the evaluation by multi-disciplinary team (MDT). Inclusion criteria: (1) primary rectal cancer undergoing radical surgery without distant metastasis; (2) PRRC was diagnosed; (3) complete inpatient, outpatient and follow-up data. According to the above criteria, clinical data of 72 patients with PRRC in Peking University People′s Hospital from January 2008 to December 2017 were retrospectively analyzed. The clinicopathological features and follow-up data were summarized. Cox proportional hazard models was used to analyze the prognostic factors of PRRC.Results:Among 72 patients, 45 were male and 27 were female with a male-to-female ratio of 1.7:1.0. The median age at recurrence was 58 (34 to 83) years and the median interval from surgery to recurrence was 2.0 (0.2 to 17.0) years. The main symptom was pain in 48.6% (35/72) of patients. In addition, gastrointestinal symptoms were found in 25.0% (18/72) of patients. The presacral recurrent sites were presacral fascia in 36 (50.0%) patients, lower sacrum (S3~S5 or coccyx) in 25 (34.7%) patients, and higher sacrum (S1~S2) in 11 (15.3%) patients. Forty-seven (65.3%) patients underwent radical surgery (abdominal resection, abdominoperineal resection, sacrectomy, abdominosacral resection), 12 (16.7%) underwent non-radical surgery (colostomy, cytoreductive surgery), and 13 (18.1%) did not undergo any surgery but only receive palliative chemoradiotherapy and nutritional support treatment. Thirty-three (45.8%) patients received radiotherapy and/or chemotherapy (oxaliplatin, 5-fluorouracil, capecitabine, irinotecan, etc.). All the patients received follow-up, and the median follow-up time was 19 (2 to 72) months. The median overall survival time was 14 (1 to 65) months. The 1- and 3-year overall survival rates were 67.1% and 32.0%, respectively. Univariate analysis showed that age at recurrence ( P=0.031) and radical resection ( P<0.001) were associated with prognosis. Multivariate analysis demonstrated that radical resection was independent factor of good prognosis (RR=0.140, 95%CI: 0.061-0.322, P<0.001). Conclusions:Patients tend to develop presacral recurrent rectal cancer within 2 years after primary surgery. The main symptom is pain. Patients undergoing radical resection have a relatively good prognosis.

Objective:To compare the postoperative functional prognosis of transanal mesorectal excision (taTME) and conventional total mesorectal excision (TME) in rectal cancer.Methods:Totally 49 patients underwent taTME and 478 patients underwent conventional TME at Department of Gastroenterological Surgery, Peking University People′s Hospital from January 2015 to December 2019 were retrospectively collected. Propensity score matching method was used to perform 1 versus 1 matching between the taTME and conventional TME groups, and 36 pairs of patients were successfully matched. After matching, the median age of patients in taTME group and conventional TME group was 60.5 (16.0) years and 60.5 (13.0) years ( M( Q R)), respectively, and the proportion of male patients was 66.7% (24/36) and 55.6% (20/36) , respectively. EORTC QLQ-C30 scale was used to assess quality of life, low anterior resection syndrome (LARS) scale and Wexner constipation score were used to evaluate anal function, international prostate symptom score (IPSS) was used to evaluate urinary function,international index of erectile function (IIEF) -5 and female sexual function index (FSFI) score were used to evaluate male and female sexual function, respectively, and generalized anxiety disorder (GAD-7) and patient health questionnaire (PHQ-9) scale were used to evaluate psych function. The t test, Mann-Whitney U test, χ 2 test, and Fisher exact test were used for comparison between groups, and Wilcoxon rank sum test or McNemar test was used for comparison between paired data. Results:There were no significant differences in surgery time, postoperative hospital stays, conversion rate, morbidity rate, surgery cost, and numbers of lymph node yield between the two groups (all P>0.05). Compared with the conventional TME group, the intraoperative blood loss in the taTME group was significantly higher (100 (100) ml vs. 80 (50) ml, U=424.5, P=0.010), the prophylactic stoma rate was significantly higher (96.9%(31/36) vs. 63.6%(21/36), χ 2=11.218, P<0.01), the total hospitalization cost was significantly lower (74 297.7 (16 746.4) CNY vs. 91 781.3 (26 228.4) CNY, U=413.0, P=0.008). There were no significant differences in anal and urinary function between the two groups (LARS scalescore: Z=-0.513, P=0.608, Wexner constipation score: Z=-0.992, P=0.321, IPSS: Z=-1.807, P=0.071). In terms of psych function, significant difference in GAD-7 scale was seen between the two groups ( Z=-2.311, P=0.021), patients with generalized anxiety disorder accounting for 26.7% (8/30) and 46.9% (15/32), respectively. Conclusions:Compared with conventional TME surgery, taTME has a significantly increased blood loss and prophylactic stoma rate. There are no significant difference in the incidence of postoperative anal, urinary, and sexual dysfunction between taTME and conventinal TME. taTME can alleviate the financial burden and general anxiety disorder to a certain extent.