Background/Aims: We investigated the clinical practice patterns of Korean endoscopists for the endoscopic resection of colorectal polyps. Methods: From September to November 2021, an online survey was conducted regarding the preferred resection methods for colorectal polyps, and responses were compared with the international guidelines. Results: Among 246 respondents, those with <4 years, 4–9 years, and ≥10 years of experiencein colonoscopy practices accounted for 25.6%, 34.1%, and 40.2% of endoscopists, respectively. The most preferred resection methods for non-pedunculated lesions were cold forceps polypectomy for ≤3 mm lesions (81.7%), cold snare polypectomy for 4–5 mm (61.0%) and 6–9 mm (43.5%) lesions, hot endoscopic mucosal resection (EMR) for 10–19 mm lesions (72.0%), precut EMR for 20–25 mm lesions (22.0%), and endoscopic submucosal dissection (ESD) for ≥26 mm lesions (29.3%). Hot EMR was favored for pedunculated lesions with a head size <20 mm and stalk size <10 mm (75.6%) and for those with a head size ≥20 mm or stalk size ≥10 mm (58.5%). For suspected superficial and deep submucosal lesions measuring 10–19 mm and ≥20 mm, ESD (26.0% and 38.6%) and surgery (36.6% and 46.3%) were preferred, respectively. The adherence rate to the guidelines ranged from 11.2% to 96.9%, depending on the size, shape, and histology of the lesions. Conclusions Adherence to the guidelines for endoscopic resection techniques varied depend-ing on the characteristics of colorectal polyps. Thus, an individualized approach is required to increase adherence to the guidelines.

Background/Aims: We investigated the clinical practice patterns of Korean endoscopists for the endoscopic resection of colorectal polyps. Methods: From September to November 2021, an online survey was conducted regarding the preferred resection methods for colorectal polyps, and responses were compared with the international guidelines. Results: Among 246 respondents, those with <4 years, 4–9 years, and ≥10 years of experiencein colonoscopy practices accounted for 25.6%, 34.1%, and 40.2% of endoscopists, respectively. The most preferred resection methods for non-pedunculated lesions were cold forceps polypectomy for ≤3 mm lesions (81.7%), cold snare polypectomy for 4–5 mm (61.0%) and 6–9 mm (43.5%) lesions, hot endoscopic mucosal resection (EMR) for 10–19 mm lesions (72.0%), precut EMR for 20–25 mm lesions (22.0%), and endoscopic submucosal dissection (ESD) for ≥26 mm lesions (29.3%). Hot EMR was favored for pedunculated lesions with a head size <20 mm and stalk size <10 mm (75.6%) and for those with a head size ≥20 mm or stalk size ≥10 mm (58.5%). For suspected superficial and deep submucosal lesions measuring 10–19 mm and ≥20 mm, ESD (26.0% and 38.6%) and surgery (36.6% and 46.3%) were preferred, respectively. The adherence rate to the guidelines ranged from 11.2% to 96.9%, depending on the size, shape, and histology of the lesions. Conclusions Adherence to the guidelines for endoscopic resection techniques varied depend-ing on the characteristics of colorectal polyps. Thus, an individualized approach is required to increase adherence to the guidelines.

Background/Aims: We investigated the clinical practice patterns of Korean endoscopists for the endoscopic resection of colorectal polyps. Methods: From September to November 2021, an online survey was conducted regarding the preferred resection methods for colorectal polyps, and responses were compared with the international guidelines. Results: Among 246 respondents, those with <4 years, 4–9 years, and ≥10 years of experiencein colonoscopy practices accounted for 25.6%, 34.1%, and 40.2% of endoscopists, respectively. The most preferred resection methods for non-pedunculated lesions were cold forceps polypectomy for ≤3 mm lesions (81.7%), cold snare polypectomy for 4–5 mm (61.0%) and 6–9 mm (43.5%) lesions, hot endoscopic mucosal resection (EMR) for 10–19 mm lesions (72.0%), precut EMR for 20–25 mm lesions (22.0%), and endoscopic submucosal dissection (ESD) for ≥26 mm lesions (29.3%). Hot EMR was favored for pedunculated lesions with a head size <20 mm and stalk size <10 mm (75.6%) and for those with a head size ≥20 mm or stalk size ≥10 mm (58.5%). For suspected superficial and deep submucosal lesions measuring 10–19 mm and ≥20 mm, ESD (26.0% and 38.6%) and surgery (36.6% and 46.3%) were preferred, respectively. The adherence rate to the guidelines ranged from 11.2% to 96.9%, depending on the size, shape, and histology of the lesions. Conclusions Adherence to the guidelines for endoscopic resection techniques varied depend-ing on the characteristics of colorectal polyps. Thus, an individualized approach is required to increase adherence to the guidelines.

Background/Aims: We investigated the clinical practice patterns of Korean endoscopists for the endoscopic resection of colorectal polyps. Methods: From September to November 2021, an online survey was conducted regarding the preferred resection methods for colorectal polyps, and responses were compared with the international guidelines. Results: Among 246 respondents, those with <4 years, 4–9 years, and ≥10 years of experiencein colonoscopy practices accounted for 25.6%, 34.1%, and 40.2% of endoscopists, respectively. The most preferred resection methods for non-pedunculated lesions were cold forceps polypectomy for ≤3 mm lesions (81.7%), cold snare polypectomy for 4–5 mm (61.0%) and 6–9 mm (43.5%) lesions, hot endoscopic mucosal resection (EMR) for 10–19 mm lesions (72.0%), precut EMR for 20–25 mm lesions (22.0%), and endoscopic submucosal dissection (ESD) for ≥26 mm lesions (29.3%). Hot EMR was favored for pedunculated lesions with a head size <20 mm and stalk size <10 mm (75.6%) and for those with a head size ≥20 mm or stalk size ≥10 mm (58.5%). For suspected superficial and deep submucosal lesions measuring 10–19 mm and ≥20 mm, ESD (26.0% and 38.6%) and surgery (36.6% and 46.3%) were preferred, respectively. The adherence rate to the guidelines ranged from 11.2% to 96.9%, depending on the size, shape, and histology of the lesions. Conclusions Adherence to the guidelines for endoscopic resection techniques varied depend-ing on the characteristics of colorectal polyps. Thus, an individualized approach is required to increase adherence to the guidelines.

Background/Aims: We investigated the clinical practice patterns of post-polypectomy colonoscopic surveillance among Korean endoscopists. Methods: In a web-based survey conducted between September and November 2021, participants were asked about their preferred surveillance intervals and the patient age at which surveillance was discontinued. Adherence to the recent guidelines of the U.S. Multi-Society Task Force on Colorectal Cancer (USMSTF) was also analyzed. Results: In total, 196 endoscopists completed the survey. The most preferred first surveillance intervals were: a 5-year interval after the removal of 1–2 tubular adenomas < 10 mm; a 3-year interval after the removal of 3–10 tubular adenomas < 10 mm, adenomas ≥ 10 mm, tubulovillous or villous adenomas, ≤ 20 hyperplastic polyps < 10 mm, 1–4 sessile serrated lesions (SSLs) < 10 mm, hyperplastic polyps or SSLs ≥ 10 mm, and traditional serrated adenomas; and a 1-year interval after the removal of adenomas with highgrade dysplasia, >10 adenomas, 5–10 SSLs, and SSLs with dysplasia. In piecemeal resections of large polyps ( > 20 mm), surveillance colonoscopy was mostly preferred after 1 year for adenomas and 6 months for SSLs. The mean USMSTF guideline adherence rate was 30.7%. The largest proportion of respondents (40.8%–55.1%) discontinued the surveillance at the patient age of 80–84 years. Conclusions A significant discrepancy was observed between the preferred post-polypectomy surveillance intervals and recent international guidelines. Individualized measures are required to increase adherence to the guidelines.

Drug resistance presents one of the major causes for the failure of cancer chemotherapy. Cancer stem-like cells (CSCs), a population of self-renewal cells with high tumorigenicity and innate chemoresistance, can survive conventional chemotherapy and generate increased resistance. Here, we develop a lipid-polymer hybrid nanoparticle for co-delivery and cell-distinct release of the differentiation-inducing agent, all-trans retinoic acid and the chemotherapeutic drug, doxorubicin to overcome the CSC-associated chemoresistance. The hybrid nanoparticles achieve differential release of the combined drugs in the CSCs and bulk tumor cells by responding to their specific intracellular signal variation. In the hypoxic CSCs, ATRA is released to induce differentiation of the CSCs, and in the differentiating CSCs with decreased chemoresistance, DOX is released upon elevation of reactive oxygen species to cause subsequent cell death. In the bulk tumor cells, the drugs are released synchronously upon the hypoxic and oxidative conditions to exert potent anticancer effect. This cell-distinct drug release enhances the synergistic therapeutic efficacy of ATRA and DOX with different anticancer mechanism. We show that treatment with the hybrid nanoparticle efficiently inhibit the tumor growth and metastasis of the CSC-enriched triple negative breast cancer in the mouse models.

Objective: To analyze the course of disease and epidemiological parameters of COVID-19 and provide evidence for making prevention and control strategies. Methods: To display the distribution of course of disease of the infectors who had close contacts with COVID-19 cases from January 1 to March 15, 2020 in Guangdong Provincial, the models of Lognormal, Weibull and gamma distribution were applied. A descriptive analysis was conducted on the basic characteristics and epidemiological parameters of course of disease. Results: In total, 515 of 11 580 close contacts were infected, with an attack rate about 4.4%, including 449 confirmed cases and 66 asymptomatic cases. Lognormal distribution was fitting best for latent period, incubation period, pre-symptomatic infection period of confirmed cases and infection period of asymptomatic cases; Gamma distribution was fitting best for infectious period and clinical symptom period of confirmed cases; Weibull distribution was fitting best for latent period of asymptomatic cases. The latent period, incubation period, pre-symptomatic infection period, infectious period and clinical symptoms period of confirmed cases were 4.50 (95%CI:3.86-5.13) days, 5.12 (95%CI:4.63-5.62) days, 0.87 (95%CI:0.67-1.07) days, 11.89 (95%CI:9.81-13.98) days and 22.00 (95%CI:21.24-22.77) days, respectively. The latent period and infectious period of asymptomatic cases were 8.88 (95%CI:6.89-10.86) days and 6.18 (95%CI:1.89-10.47) days, respectively. Conclusion: The estimated course of COVID-19 and related epidemiological parameters are similar to the existing data.
COVID-19 ; Cohort Studies ; Contact Tracing ; Humans ; Incidence ; Prospective Studies

【Objective】 To provide data reference for the implementation of the homogenization of pre-donation blood testing by investigating the relevant situation of pre-donation blood testing in various blood services in Chongqing and analyzing their differences. 【Methods】 A questionnaire covering the basic information of pre-donation blood testing items, quality control and the management of deferral donors was developed, and issued to 19 blood services in Chongqing through E-mails by Chongqing Society of Blood Transfusion. The data collected were sorted, revised and analyzed. 【Results】 A total of 19 questionnaires from 19 blood services(including 1 blood center, 1 sub-center, 6 central blood stations and 11 central blood banks) were collected. All of the pre-donation blood test items of 19 blood services met the Blood Donor Health Test Requirements. Hemoglobin, blood group, ALT and HBsAg testing were carried out by 19 blood services, anti-TP testing by 15, and lipid blood testing by 11, using different detection methods and reagents. Significant differences were found in the frequency and rules of internal quality control for quantitative testing items. In addition, the deferral time and re-recruitment strategy of deferral blood donors were also significantly different. 【Conclusion】 There were differences in the management of pre-donation blood testing and blood donor management after blood donation among blood services in Chongqing. Further standardization was needed to realize regional homogenization and guarantee blood safety and the safety of blood donors.

Objective:To explore the establishment and assessment of the depression model of adult SD rats induced by early maternal infant separation stress combined with adult chronic unpredictable mild stress(CUMS), and to observe the behavior and synaptic protein expression of SD rats.Methods:Twenty-four male rats were randomly divided into three groups: control group (CON group), chronic unpredictable stress group (CUMS group), maternal infant separation combined with chronic unpredictable stress group (MS + CUMS group). The depression model of rats in cums group was established by CUMS, and the depression model of rats in MS + CUMS group was established by maternal infant separation + CUMS. The depression model was evaluated by body mass and appearance observation, sugar water preference experiment, open field test and forced swimming test.Synapse-associated proteins (PSD-95 and synaptophysin (Syn)) of the hippocampus were assayed using Western blot. Syn protein expression was measured by immunohistochemistry.Results:After modeling, compared with CON group, the rats in CUMS group and MS + CUMS group had significantly lower body mass((126.43±3.88) g, (91.04±3.85) g, (69.89±6.67) g; t=5.03, 8.03, both P<0.01), significantly lower sugar water preference((94.21±0.56)%, (79.30±1.13)%, (72.73±1.82)%; t=8.24, 11.87, both P<0.01) and significantly increased immobility time((3.50±0.84)s, (13.59±2.40)s, (15.70±2.97)s; t=3.16, 3.82, both P<0.01). Among them, the body mass and sugar water preference of MS + CUMS group were lower than those of CUMS group ( t=3.00, 3.63; both P<0.01). (2)The center time of the rats in MS+ CUMS group markedly reduced compared with that of CON group((21.41±4.65) s, (8.96±2.37) s; t=2.66, P<0.05). (3)In the immunohistochemistry experiment, compared with the CON group, the percentage of Syn positive area in hippocampus of rats in CUMS group and MS+ CUMS group decreased significantly ((24.42±0.76)%, (14.00±0.95)%, (10.38±1.38)%; t=6.93, 9.33, P<0.01). (4)The results of Western blot showed that compared with CON group, both the expression of PSD-95 ((1.18±0.02), (0.74±0.06), (0.52±0.05), t=6.29, 9.31; both P<0.05) and Syn ((1.12±0.08), (0.95±0.06), (0.90±0.07); t=3.10, 4.04; both P<0.05) in hippocampus of rats in CUMS group and MS+ CUMS group were significantly decreased.And compared with the CUMS group, the expression of PSD-95 in MS+ CUMS group was lower( t=0.93, P<0.05). Conclusion:The method of MS combined with CUMS can effectively induce depression like behavior and decrease the expression of synaptic plasticity related protein of hippocampus in rats.

OBJECTIVE: Pyrotinib, a novel irreversible pan-ErbB receptor tyrosine kinase inhibitor, showed promising antitumor activity and acceptable tolerability in phase II and phase III randomized clinical trials. We assessed the activity and safety of oral pyrotinib for human epidermal growth factor receptor 2 (HER2) positive metastatic breast cancer patients in the real world. METHODS: We retrospectively analyzed 72 HER2 positive metastatic breast cancer (MBC) patients who received oral pyrotinib based regimens at Beijing Cancer Hospital and other four hospitals (Peking University First Hospital, China-Japan Friendship Hospital, General Hospital of PLA, Peking University Third Hospital) from August 2018 to September 2019. Progression free survival (PFS), objective response rate (ORR), adverse events (AE) of pyrotinib were investigated. RESULTS: Seventy-two patients with HER2 positive MBC were enrolled. The median age of the patients was 55 years (range: 32-79 years). Sixty-nine (95.8%) patients had received anti-HER2 treatment in the metastatic and/or (neo) adjuvant settings; 61 (84.7%) patients had received anti-HER2 treatments in the metastatic setting in terms of trastuzumab 56 (77.8%) patients, lapatinib 36 (50.0%) patients, and T-DM1 4 (5.6%) patients. Among these 72 patients who received oral pyrotinib based regimens, 62 (86.1%) patients received pyrotinib (±trastuzumab) in combination with chemotherapy, 6 (8.3%) patients received pyrotinib (± trastuzumab) in combination with endocrine therapy and 4 (5.6%) patients received pyrotinib (±trastuzumab). Sixty-five (90.3%) patients received 400 mg pyrotinib once daily as initial dose, and 7 (9.7%) patients received 320 mg. OBJECTIVE response and safety to pyrotinib based therapy were evaluable in all the 72 patients. One (1.4%) patient achieved complete response (CR), 18 (25.0%) patients achieved partial response (PR), 41 (56.9%) patients had stable disease (SD), and 12 (16.7%) patients had progressive disease (PD). The ORR (CR+PR) was 26.4% and the median PFS was 7.6 months (95%CI: 5.5-9.7 months). Among the 36 patients with prior lapatinib therapy, the median PFS was 7.9 months (95%CI: 4.1-11.7 months). Among the 15 patients with brain metastasis, the median PFS was 6.0 months (95%CI: 2.2-9.8 months). The main toxicities related to pyrotinib were diarrhea in 57 (79.2%) cases, and 48 (66.7%) cases with grade 1-2 as well as 9 (12.5%) cases with grade 3. CONCLUSION Pyrotinib based therapy is an effective treatment for patients with HER2 positive MBC, including patients with lapatinib treatment failure and brain metastasis, and the toxicities can be tolerated.
Acrylamides/therapeutic use* ; Adult ; Aged ; Aminoquinolines/therapeutic use* ; Antineoplastic Combined Chemotherapy Protocols ; Breast Neoplasms/drug therapy* ; China ; Humans ; Middle Aged ; Neoplasm Metastasis ; Receptor, ErbB-2 ; Retrospective Studies ; Trastuzumab ; Treatment Outcome