Neutralizing antibodies have been designed to specifically target and bind to the receptor binding domain (RBD) of spike (S) protein to block severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus from attaching to angiotensin converting enzyme 2 (ACE2). This study reports a distinctive nanobody, designated as VHH21, that directly catalyzes the S-trimer into an irreversible transition state through postfusion conformational changes. Derived from camels immunized with multiple antigens, a set of nanobodies with high affinity for the S1 protein displays abilities to neutralize pseudovirion infections with a broad resistance to variants of concern of SARS-CoV-2, including SARS-CoV and BatRaTG13. Importantly, a super-resolution screening and analysis platform based on visual fluorescence probes was designed and applied to monitor single proteins and protein subunits. A spontaneously occurring dimeric form of VHH21 was obtained to rapidly destroy the S-trimer. Structural analysis via cryogenic electron microscopy revealed that VHH21 targets specific conserved epitopes on the S protein, distinct from the ACE2 binding site on the RBD, which destabilizes the fusion process. This research highlights the potential of VHH21 as an abzyme-like nanobody (nanoabzyme) possessing broad-spectrum binding capabilities and highly effective anti-viral properties and offers a promising strategy for combating coronavirus outbreaks.
Single-Domain Antibodies/immunology* ; Spike Glycoprotein, Coronavirus/metabolism* ; SARS-CoV-2/immunology* ; Animals ; Humans ; Antibodies, Neutralizing/immunology* ; Camelus ; COVID-19/immunology* ; Antibodies, Viral/immunology* ; Angiotensin-Converting Enzyme 2

Objective:To evaluate whether additional radical surgery is necessary following non-curative endoscopic resection of early colorectal cancer.Method:Clinicopathological data in 104 patients following non-curative endoscopic resection of early colorectal coucer at the Department of General Surgery, Peking University First Hospital between Jan 2011 and Dec 2021.Results:Lymph node metastasis and/or residual cancer was found in 23 patients (22%), including 12 cases of lymph node metastasis, 7 cases of residual cancer and 4 patients with both residual cancer and lymph node metastasis. Univariate analysis indicated that vascular infiltration, positive vertical margin, and female gender were risk factors for lymph node metastasis. Risk factors for residual cancer were tumors ≥2 cm in size, negative lift sign, infiltration depth of ≥1 000 μm, and positive horizontal and vertical margins. Multivariate Logistic regression analysis revealed that vascular invasion, positive vertical margins, and being female were independent risk factors for lymph node metastasis, while positive vertical margins was independent risk factor for residual cancer. Salvage surgery lasted for a median of 184 (156-233) minutes, with an estimated blood loss of 50 (20-100) ml and an average postoperative hospital stay of 9 (8-11) days. Seven cases of Clavein-Dindo Ⅱ or higher complications were observed, including pulmonary embolism in 1 case , anastomotic leakage in one, lymphatic fistula in one, bowel obstruction in 2 cases and urinary tract infection in 2 cases.Conclusion:Salvage surgery is mandatory for early endoscopic non-curative resection of colorectal cancer.

Radiotherapy (RT) is one of the most common treatments for cancer. However, intracellular glutathione (GSH) plays a key role in protecting cancer from radiation damage. Herein, we have developed a platelet membrane biomimetic nanomedicine (PMD) that induces double GSH consumption to enhance tumor radioimmunotherapy. This biomimetic nanomedicine consists of an external platelet membrane and internal organic mesoporous silica nanoparticles (MON) loaded with 2-deoxy-D-glucose (2-DG). Thanks to the tumor-targeting ability of the platelet membranes, PMD can target and aggregate to the tumor site, which is internalized by tumor cells. Within tumor cells overexpressing GSH, MON reacts with GSH to degrade and release 2-DG. This step initially depletes the intracellular GSH content. The subsequent release of 2-DG inhibits glycolysis and adenosine triphosphate (ATP) production, ultimately leading to secondary GSH consumption. This nanodrug combines dual GSH depletion, starvation therapy, and RT to promote immunogenic cell death and stimulate the systemic immune response. In the bilateral tumor model in vivo, distal tumor growth was also well suppressed. The proportion of mature dendritic cells (DC) and CD8⁺ T cells in the mice was increased. This indicates that PMD can promote anti-tumor radioimmunotherapy and has good prospects for clinical application.

【Objective】 To investigate the effects of preoperative ureteroscopy (URS) on the intravesical recurrence (IVR) in patients with upper tract urothelial carcinoma (UTUC) after radical nephroureterectomy (RNU). 【Methods】 The clinical data of 241 UTUC patients treated during May 2012 and Jan.2020 in the Second Hospital of Laozhou University were retrospectively analyzed. The patients were divided into URS before RNU group (URS group) and non-URS before RNU group (non-URS group). The cumulative IVR rate, progression-free survival (PFS) and overall survival (OS) after RNU were compared, and the survival curve was drawn. Cox proportional hazards models were used to assess risk factors affecting IVR. 【Results】 Of the 241 patients, 64 (26.6%) were included in the URS group and 177 (73.4%) in the non-URS group. In the URS group, 49 underwent biopsy and 15 did not. All patients were followed up for a median of 44 (3 to 122) months, with a median time to recurrence of 12 (3 to 56) months. IVR occurred in 18 patients (28.1%) in the URS group and 25 (14.1%) in the non-URS group. Kaplan-Meier survival analysis showed that the cumulative IVR rate was higher in the URS group than in the non-URS group (all P<0.05), regardless of whether patients had a history of bladder cancer (BC) or not, while PFS was lower in the URS group than in the non-URS group (P=0.007). Cox multivariate regression analysis showed that URS (P=0.031) and complicated renal pelvis tumor and ureteral tumor (P=0.004) were independent risk factors for IVR. 【Conclusion】 Preoperative URS increases the incidence of IVR in patients with UTUC, and routine preoperative use of URS is not recommended.

Familial pheochromocytoma belongs to autosomal dominant inheritance, and has complex and variable clinical manifestations. A child with bilateral PHEO was admitted to our hospital. His grandmother, father and brother were all diagnosed with PHEO, and his aunt was diagnosed with paraganglioma. The child underwent laparoscopic left partial adrenalectomy and open surgery for the contralateral tumor, and was in good postoperative condition. The blood pressure returned to normal and there was no local recurrence and metastasis during the follow-up of 8 months after the second operation.

Objective:By analyzing the clinical data of patients with primary duodenal adenocarcinoma (PDA), the risk factors affecting the postoperative prognosis of PDA patients were discussed.Methods:The clinical data of 191 patients diagnosed with PDA in Peking University First Hospital from Jan 2009 to Dec 2022 were collected. The survival rate was calculated and the survival curve was plotted by Kaplan-Meier method. Univariate analysis was performed by Log-Rank test, and multivariate analysis was performed by COX proportional hazards regression model to obtain independent risk factors.Results:The median age of onset in patients with PDA is 65 years old, and the most common symptoms are abdominal pain and abdominal distension. Prognostic analysis showed that the survival rates at 1, 3 and 5 years were 73.8%, 44.6%, and 23.0%. The analysis of Cox risk proportional regression model showed that preoperative CA19-9 level, depth of tumor invasion, degree of differentiation, TNM stage, and surgical mode were independent risk factors for the prognosis of PDA (all P<0.01). Conclusion:The overall incidence of PDA is low, but the prognosis is rather poor. Multvariable factors are associated with its prognosis and surgery is still the mainstay for hope of cure.

Objective:To evaluate the safety of double and a half layered esophagojejunal anastomosis in radical gastrectomy.Methods:This prospective, multi-center, single-arm study was initiated by the Affiliated Cancer Hospital of Zhengzhou University in June 2021 (CRAFT Study, NCT05282563). Participating institutions included Nanyang Central Hospital, Zhumadian Central Hospital, Luoyang Central Hospital, First Affiliated Hospital of Henan Polytechnic University, First Affiliated Hospital of Henan University, Luohe Central Hospital, the People's Hospital of Hebi, First People's Hospital of Shangqiu, Anyang Tumor Hospital, First People's Hospital of Pingdingshan, and Zhengzhou Central Hospital Affiliated to Zhengzhou University. Inclusion criteria were as follows: (1) gastric adenocarcinoma confirmed by preoperative gastroscopy;(2) preoperative imaging assessment indicated that R0 resection was feasible; (3) preoperative assessment showed no contraindications to surgery;(4) esophagojejunostomy planned during the procedure; (5) patients volunteered to participate in this study and gave their written informed consent; (6) ECOG score 0–1; and (7) ASA score I–III. Exclusion criteria were as follows: (1) history of upper abdominal surgery (except laparoscopic cholecystectomy);(2) history of gastric surgery (except endoscopic submucosal dissection and endoscopic mucosal resection); (3) pregnancy or lactation;(4) emergency surgery for gastric cancer-related complications (perforation, hemorrhage, obstruction); (5) other malignant tumors within 5 years or coexisting malignant tumors;(6) arterial embolism within 6 months, such as angina pectoris, myocardial infarction, and cerebrovascular accident; and (7) comorbidities or mental health abnormalities that could affect patients' participation in the study. Patients were eliminated from the study if: (1) radical gastrectomy could not be completed; (2) end-to-side esophagojejunal anastomosis was not performed during the procedure; or (3) esophagojejunal anastomosis reinforcement was not possible. Double and a half layered esophagojejunal anastomosis was performed as follows: (1) Open surgery: the full thickness of the anastomosis is continuously sutured, followed by embedding the seromuscular layer with barbed or 3-0 absorbable sutures. The anastomosis is sutured with an average of six to eight stitches. (2) Laparoscopic surgery: the anastomosis is strengthened by counterclockwise full-layer sutures. Once the anastomosis has been sutured to the right posterior aspect of the anastomosis, the jejunum stump is pulled to the right and the anastomosis turned over to continue to complete reinforcement of the posterior wall. The suture interval is approximately 5 mm. After completing the full-thickness suture, the anastomosis is embedded in the seromuscular layer. Relevant data of patients who had undergone radical gastrectomy in the above 12 centers from June 2021 were collected and analyzed. The primary outcome was safety (e.g., postoperative complications, and treatment). Other studied variables included details of surgery (e.g., surgery time, intraoperative bleeding), postoperative recovery (postoperative time to passing flatus and oral intake, length of hospital stay), and follow-up conditions (quality of life as assessed by Visick scores).Result:[1] From June 2021 to September 2022,457 patients were enrolled, including 355 men and 102 women of median age 60.8±10.1 years and BMI 23.7±3.2 kg/m2. The tumors were located in the upper stomach in 294 patients, mid stomach in 139; and lower stomach in 24. The surgical procedures comprised 48 proximal gastrectomies and 409 total gastrectomies. Neoadjuvant chemotherapy was administered to 85 patients. Other organs were resected in 85 patients. The maximum tumor diameter was 4.3±2.2 cm, number of excised lymph nodes 28.3±15.2, and number of positive lymph nodes five (range one to four. As to pathological stage,83 patients had Stage I disease, 128 Stage II, 237 Stage III, and nine Stage IV. [2] The studied surgery-related variables were as follows: The operation was successfully completed in all patients, 352 via a transabdominal approach, 25 via a transhiatus approach, and 80 via a transthoracoabdominal approach. The whole procedure was performed laparoscopically in 53 patients (11.6%), 189 (41.4%) underwent laparoscopic-assisted surgery, and 215 (47.0%) underwent open surgery. The median intraoperative blood loss was 200 (range, 10–1 350) mL, and the operating time 215.6±66.7 minutes. The anastomotic reinforcement time was 2 (7.3±3.9) minutes for laparoscopic-assisted surgery, 17.6±1.7 minutes for total laparoscopy, and 6.0±1.2 minutes for open surgery. [3] The studied postoperative variables were as follows: The median time to postoperative passage of flatus was 3.1±1.1 days and the postoperative gastrointestinal angiography time 6 (range, 4–13) days. The median time to postoperative oral intake was 7 (range, 2–14) days, and the postoperative hospitalization time 15.8±6.7 days. [4] The safety-related variables were as follows: In total, there were 184 (40.3%) postoperative complications. These comprised esophagojejunal anastomosis complications in 10 patients (2.2%), four (0.9%) being anastomotic leakage (including two cases of subclinical leakage and two of clinical leakage; all resolved with conservative treatment); and six patients (1.3%) with anastomotic stenosis (two who underwent endoscopic balloon dilation 21 and 46 days after surgery, the others improved after a change in diet). There was no anastomotic bleeding. Non-anastomotic complications occurred in 174 patients (38.1%). All patients attended for follow-up at least once, the median follow-up time being 10 (3–18) months. Visick grades were as follows: Class I, 89.1% (407/457); Class II, 7.9% (36/457); Class III, 2.6% (12/457); and Class IV 0.4% (2/457).Conclusion:Double and a half layered esophagojejunal anastomosis in radical gastrectomy is safe and feasible.

Objective:To evaluate the safety of double and a half layered esophagojejunal anastomosis in radical gastrectomy.Methods:This prospective, multi-center, single-arm study was initiated by the Affiliated Cancer Hospital of Zhengzhou University in June 2021 (CRAFT Study, NCT05282563). Participating institutions included Nanyang Central Hospital, Zhumadian Central Hospital, Luoyang Central Hospital, First Affiliated Hospital of Henan Polytechnic University, First Affiliated Hospital of Henan University, Luohe Central Hospital, the People's Hospital of Hebi, First People's Hospital of Shangqiu, Anyang Tumor Hospital, First People's Hospital of Pingdingshan, and Zhengzhou Central Hospital Affiliated to Zhengzhou University. Inclusion criteria were as follows: (1) gastric adenocarcinoma confirmed by preoperative gastroscopy;(2) preoperative imaging assessment indicated that R0 resection was feasible; (3) preoperative assessment showed no contraindications to surgery;(4) esophagojejunostomy planned during the procedure; (5) patients volunteered to participate in this study and gave their written informed consent; (6) ECOG score 0–1; and (7) ASA score I–III. Exclusion criteria were as follows: (1) history of upper abdominal surgery (except laparoscopic cholecystectomy);(2) history of gastric surgery (except endoscopic submucosal dissection and endoscopic mucosal resection); (3) pregnancy or lactation;(4) emergency surgery for gastric cancer-related complications (perforation, hemorrhage, obstruction); (5) other malignant tumors within 5 years or coexisting malignant tumors;(6) arterial embolism within 6 months, such as angina pectoris, myocardial infarction, and cerebrovascular accident; and (7) comorbidities or mental health abnormalities that could affect patients' participation in the study. Patients were eliminated from the study if: (1) radical gastrectomy could not be completed; (2) end-to-side esophagojejunal anastomosis was not performed during the procedure; or (3) esophagojejunal anastomosis reinforcement was not possible. Double and a half layered esophagojejunal anastomosis was performed as follows: (1) Open surgery: the full thickness of the anastomosis is continuously sutured, followed by embedding the seromuscular layer with barbed or 3-0 absorbable sutures. The anastomosis is sutured with an average of six to eight stitches. (2) Laparoscopic surgery: the anastomosis is strengthened by counterclockwise full-layer sutures. Once the anastomosis has been sutured to the right posterior aspect of the anastomosis, the jejunum stump is pulled to the right and the anastomosis turned over to continue to complete reinforcement of the posterior wall. The suture interval is approximately 5 mm. After completing the full-thickness suture, the anastomosis is embedded in the seromuscular layer. Relevant data of patients who had undergone radical gastrectomy in the above 12 centers from June 2021 were collected and analyzed. The primary outcome was safety (e.g., postoperative complications, and treatment). Other studied variables included details of surgery (e.g., surgery time, intraoperative bleeding), postoperative recovery (postoperative time to passing flatus and oral intake, length of hospital stay), and follow-up conditions (quality of life as assessed by Visick scores).Result:[1] From June 2021 to September 2022,457 patients were enrolled, including 355 men and 102 women of median age 60.8±10.1 years and BMI 23.7±3.2 kg/m2. The tumors were located in the upper stomach in 294 patients, mid stomach in 139; and lower stomach in 24. The surgical procedures comprised 48 proximal gastrectomies and 409 total gastrectomies. Neoadjuvant chemotherapy was administered to 85 patients. Other organs were resected in 85 patients. The maximum tumor diameter was 4.3±2.2 cm, number of excised lymph nodes 28.3±15.2, and number of positive lymph nodes five (range one to four. As to pathological stage,83 patients had Stage I disease, 128 Stage II, 237 Stage III, and nine Stage IV. [2] The studied surgery-related variables were as follows: The operation was successfully completed in all patients, 352 via a transabdominal approach, 25 via a transhiatus approach, and 80 via a transthoracoabdominal approach. The whole procedure was performed laparoscopically in 53 patients (11.6%), 189 (41.4%) underwent laparoscopic-assisted surgery, and 215 (47.0%) underwent open surgery. The median intraoperative blood loss was 200 (range, 10–1 350) mL, and the operating time 215.6±66.7 minutes. The anastomotic reinforcement time was 2 (7.3±3.9) minutes for laparoscopic-assisted surgery, 17.6±1.7 minutes for total laparoscopy, and 6.0±1.2 minutes for open surgery. [3] The studied postoperative variables were as follows: The median time to postoperative passage of flatus was 3.1±1.1 days and the postoperative gastrointestinal angiography time 6 (range, 4–13) days. The median time to postoperative oral intake was 7 (range, 2–14) days, and the postoperative hospitalization time 15.8±6.7 days. [4] The safety-related variables were as follows: In total, there were 184 (40.3%) postoperative complications. These comprised esophagojejunal anastomosis complications in 10 patients (2.2%), four (0.9%) being anastomotic leakage (including two cases of subclinical leakage and two of clinical leakage; all resolved with conservative treatment); and six patients (1.3%) with anastomotic stenosis (two who underwent endoscopic balloon dilation 21 and 46 days after surgery, the others improved after a change in diet). There was no anastomotic bleeding. Non-anastomotic complications occurred in 174 patients (38.1%). All patients attended for follow-up at least once, the median follow-up time being 10 (3–18) months. Visick grades were as follows: Class I, 89.1% (407/457); Class II, 7.9% (36/457); Class III, 2.6% (12/457); and Class IV 0.4% (2/457).Conclusion:Double and a half layered esophagojejunal anastomosis in radical gastrectomy is safe and feasible.

Objective:To investigate the effects of compound fermented milk on intestinal microbiota, short chain fatty acid (SCFA), intestinal motility and mucosal barrier in mice with constipation.Methods:Twenty-seven C57BL/6JNifdc mice were randomly divided into three groups: control group, model group and intervention group. The model group and the intervention group were given loperamide intragastrically for two weeks. Starting from the second week, the intervention group was treated with compound fermented milk for 7 d. The control group was given normal saline. Food intake, water intake, weight change, fecal moisture content, time of first-time black stool and small intestine propulsion rate were detected. Expression of serotonin C receptor (5-HTR2C), zona occludins-1 (ZO-1) and mucin-2 (MUC-2) at mRNA level in colon was analyzed. Western blot was used to measure the expression of Raf/ERK/MAPK-related proteins. SCFA level in intestinal tract was detected by gas chromatography. Intestinal microbiota diversity was analyzed by high-throughput sequencing.Results:Compared with the control group, the first black stool excretion time was significantly prolonged in the model group ( P<0.01). Moreover, fecal moisture content, small intestine propulsion rate and the expression of 5-HTR2C and ZO-1 at mRNA level in colon were significantly decreased ( P<0.01). Compared with the model group, the first black stool excretion time was significantly shortened ( P<0.05); fecal moisture content, small intestine propelling rate ( P<0.05), the expression of colon 5-HTR2C and ZO-1 at mRNA level ( P<0.05), phosphorylation of Raf/ERK/MAPK pathway in the colon, intestinal SCFA-producing bacteria and intestinal SCFA content were increased in the intervention group. Conclusions:Compound fermented milk had a therapeutic effect on constipation in a mouse model by increasing the abundance of SCFA-producing bacteria and SCFA content, enhancing the phosphorylation of the Raf/ERK/MAPK pathway to up-regulate the expression of 5-HTR2C at mRNA level in the colon, and increasing the expression of ZO-1 at mRNA level in the colon. Intestinal peristalsis and intestinal mucosal barrier function were enhanced, thus improving the symptom of constipation.

Objective:To observe the changes of retinal blood flow density and thickness in the macular region of eyes with high myopia (HM) combined with peripapillary intrachoroidal cavitation (PICC).Methods:A cross-sectional study. From March 2019 to May 2021, 65 patients (65 eyes) diagnosed as PICC (HM+PICC group) in Eye Hospital, China Academy of Chinese Medical Sciences, sex-and age-matched 69 HM patients of 69 eyes (HM group) and 65 healthy people of 65 eyes (control group) were enrolled in this study. The optical coherence tomography angiography was used to scan macular areas in 3 mm×3 mm, and measure the macular fovea and optic disc on superior, inferior, nasal, temporal superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density in the foveal and parafoveal region, and macular retinal ganglion cell complex (mGCC) thickness, full retinal thickness. One-way analysis of variance were used to test the difference of the index values among three groups, and then two groups were compared with Bonferroni test. A paired t-test was used to test the difference of the macular vessel density and thickness between the superior and inferior hemifield in three groups. Pearson partial regression analysis was used to calculate the correlations between them at same sites. Results:PICC was located most frequently at the inferior temporal disc border, followed by the inferior nasal region, superior temporal region, and superior nasal region in the HM+PICC group on 57(87.7%, 57/65), 25(38.5%, 25/65), 3(4.6%, 3/65) and 1(1.5%, 1/65 ) eye. There were significant differences in the global and regional full retinal thickness, mGCC thickness, SCP and DCP vessel density among 3 groups ( F=29.097, 51.929, 16.253, 6.135; P<0.001). The macular SCP and DCP vessel density except in the fovea, all regional macular full retinal thickness and mGCC thickness in the HM+PICC group were significantly lower than those in the normal group ( P<0.05). Compared to the HM group, the HM+PICC group had lower all regional mGCC thickness and SCP vessel density, as well as full retinal thickness in the inferior hemifield and DCP vessel density in the foveal region ( P<0.05). Macular vessel density and thickness in the inferior hemifield were significantly lower than those in the superior hemifield ( t=6.356, 11.693, 6.212, 2.936; P<0.01). Pearson partial regression analysis showed the SCP vessel density was positively correlated with corresponding mGCC thickness and full retinal thickness ( r=0.584, 0.534, 0.592, 0.496, 0.485, 0.517; P<0.001). However, there was no significant correlation between the DCP vascular density and mGCC thickness ( P>0.05), and only a weak positive correlation between the DCP vascular density and the full retinal thickness in the inferior hemifield ( r=0.319, P=0.014). However, no association with average and superior full retinal thickness ( r=0.066, 0.002, 0.125, 0.184, 0.016, 0.319; P>0.05). Conclusion:The macular SCP vessel density, mGCC thickness and the full retinal thickness in the inferior hemifield in PICC eyes are lower than those in the HM eyes, especially the mGCC thickness and SCP vessel density in the inferior hemifield, and there is a strong positive correlation between them.