Human embryonic stem(ES)cell research has been current hotspot of life science since 1990s.The stem cell is a kind of special and essential cell type found in human body,which can not only be amplified and self renewed,but can be derived into many kinds of cell lines.Scientists forecast that deeper research of ES cells will offer hope of new cures for leukemia,neurodegenerative diseases,and so on.While at the same time,stem cell research leads an important bioethical debate in the all world.

Databases, Protein ; Protein Structure, Secondary ; Proteins ; chemistry

Department of General practice of West China Hospital of Sichuan University has been commissioned to train general practitioner for Tibet Autonomous Region since 2015. Based on the "demand-oriented and clinical ability training", the established training framework includes four aspects: a rotation plan of general practice theory-clinical practice-community application, the closed-loop mechanism of teaching management system improvement,innovation of training assessment and teaching activities. This article summarizes the practical experience of the commissioned general practice residency training for Tibet to provide reference for the program design.

Objective:To automatically synthesize Al 18F-fibroblast activation protein inhibitor (FAPI)-74, and explore its value of clinical application. Methods:Al 18F-FAPI-74 was synthesized automatically by the commercial synthesis module CFN-MPS-100, and its yield, radiochemical purity and stability were determined. Sixteen normal Kunming (KM) mice were randomly divided into 4 groups and euthanized at 10, 30, 60 and 90 min after Al 18F-FAPI-74 injection, and the biodistribution was measured. MicroPET/CT dynamic scanning (60 min) was performed in 5 rat pancreatic tumor-bearing BALB/c nude mice to observe the tumor uptake. Al 18F-FAPI-74 PET/CT imaging was performed on 3 volunteers (1 male, 2 females; age: 37, 41, 43 years) to evaluate the clinical application value of Al 18F-FAPI-74. Results:The automated synthesis time of Al 18F-FAPI-74 was about 35 min, with the synthesis yield of (21.34±3.86)% (without attenuation correction, n=5) and the radiochemical purity more than 99%. The radiochemical purity was still more than 96% after placement at 37 ℃ for 6 h. Biodistribution in normal mice and microPET/CT dynamic scanning in tumor-bearing nude mice showed that consistently high uptake in the kidneys and bladder, and the tumor uptake was the highest at 20 min, and the maximum tumor-to-muscle ratio was 3.16±0.01 at 60 min. PET/CT imaging on volunteers showed that there was a small amount of uptake in myocardium, most organs such as the liver and lung had background uptake, and the maximum SUV max of persistent high uptake of tumor was 17.08. Conclusions:Al 18F-FAPI-74 has the advantages of simple synthesis, high yield, stable quality and good imaging performance in mice and volunteers. It is a kind of imaging agent that meets the requirements of clinical diagnosis.

Objective:To investigate the preoperative nutritional status of cardiac surgery patients in southwest China, analyze the incidence and characteristics of nutritional risk, and provide basis for establishing a standardized individualized nutritional intervention program for cardiac surgery patients.Methods:A cross-sectional survey was conducted on the nutritional status and intervention status of preoperative patients in cardiac surgery department of 23 general hospitals in Yunnan, Guizhou, Sichuan and Chongqing districts. At 00: 00 on July 7, 2022, the patients aged > 18 years old in cardiac surgery departments of the above hospitals who planned to undergo surgical treatment were enrolled as the survey objects to investigate the nutritional status on July 6, 2022 (the survey date), including basic information (general information, nutrition indicators, etc.), nutrition screening and evaluation (nutrition risk screening and organ support, etc.), nutrition treatment (nutrition supplement methods and prescriptions, etc.) and nutrition awareness of medical staff.Results:The 126 questionnaires were collected, of which 125 were valid (99.2%). ① Basic information: of the 125 patients, 67 patients were male (53.6%) and 58 patients were female (46.4%). The age ranged from 19 years old to 86 years old, with an average of (53.13±14.74) years old. Body mass index (BMI) was (22.21±3.78) kg/m 2. The age and BMI of men were significantly higher than those of women [age (years old): 56.63±13.34 vs. 49.09±15.35, BMI (kg/m 2): 22.74±3.86 vs. 21.59±3.61, both P < 0.05]. Of the 125 patients, 75 had valvular disease and 50 were with non-valvular diseases, which mainly included congenital heart disease [19 cases (15.2%)], aortic dissection [13 cases (10.4%)], coronary heart disease [12 cases (9.6%)], etc. The course of disease was 0.5 hour to 36 years, of which 93 patients (74.4%) were more than 6 months and 32 patients (25.6%) were equal to or less than 6 months. The proportion of female patients with disease duration > 6 months was significantly higher than that of male patients [87.9% (51/58) vs. 62.7% (42/67), P < 0.01]. The basic diseases mainly included hypertension [38 cases (30.4%)], coronary heart disease [12 cases (9.6%)], diabetes [7 cases (5.6%)], chronic obstructive pulmonary disease [COPD, 6 cases (4.8%)], etc. Among 125 patients, total protein (TP) < 60 g/L in 24 cases (19.2%), albumin (Alb) < 40 g/L in 64 cases (51.2%), anemia [male hemoglobin (Hb) < 120 g/L, female Hb < 110 g/L] in 33 cases (26.4%). A total of 60 cases of prealbumin data were collected, of which 23 cases (38.3%) were less than 200 mg/L.② Nutrition screening and assessment: 33.6% of the 125 patients did not undergo routine nutrition screening after admission, including the provincial and municipal tertiary hospitals. Among the 83 patients undergoing nutritional screening, 41 (32.8%) were at nutritional risk. Further analysis of patients with nutritional risk showed that of the 41 patients, 20 were male (48.8%) and 21 were female (51.2%); 27 cases (65.9%) was with valvular diseases and 14 cases (34.1%) was with non-valvular diseases; the course of disease was more than 6 months in 30 cases (73.2%), and ≤ 6 months in 11 cases (26.7%). Statistical comparison of the above 83 patients showed that women, basic disease, long term-valvular disease, anemia, low TP, and low Alb before operation were more prone to innutrition. ③ Nutritional therapy: of the 125 patients, 5 were receiving mechanical ventilation (4.0%) and 2 were using vasoactive drugs (1.6%); there were 5 cases with gastrointestinal dysfunction (4.0%), mainly manifested as abdominal distension, abdominal pain, constipation and diarrhea. One patient was treated with enteral nutrition through gastric tube combined with parenteral nutrition support, 124 patients were fed orally, and an irregular phenomenon of injecting amino acid fat emulsion through peripheral vein in 2 patients. ④ Nutrition awareness of medical staff: 124 (99.2%) of the 125 patients had a nutrition department in their hospital; 71 cases (56.8%) received nutrition education, of which 37 cases (52.1%) were consulted by the nutrition department. Of all the cases, only 38 (30.4%) were consulted by the nutrition department, of which 1 (2.6%) did not receive nutrition education after consultation. Conclusions:At present, the incidence of preoperative malnutrition in patients undergoing cardiac surgery is high in southwest China. The incidence of malnutrition in patients with basic diseases, long term-valvular disease, low TP, low Alb and anemia before operation is higher, and the incidence of malnutrition is hidden in women. The course of disease of women is longer than that of men at the time of treatment, and malnutrition is more likely to occur. The attending physicians should pay attention to the above groups. It is necessary to establish a standardized individualized nutritional intervention program and apply it to actual clinical diagnosis and treatment, so as to ultimately improve the prognosis of patients undergoing cardiac surgery and increase the benefits of patients in treatment.