Objective To use direct dilution method to pretreat human urine, and to determine 19 elements in human urine using inductively coupled plasma mass spectrometry, and to evaluate the uncertainty of the entire experimental process. Methods The relevant mathematical models were established according to JJF 10591-2012 ^“Evaluation and Expression of Measurement Uncertainty^” and CNAS-GL006 ^“Guidance for Evaluation of Uncertainty in Chemical Analysis^”. Taking molybdenum as an example, the uncertainty sources in the determination of 19 elements in human urine by inductively coupled plasma method were analyzed and evaluated, including sample pretreatment, sample repeated measurement, standard solution preparation and standard curve fitting. Results The extended uncertainty of molybdenum in human urine is 2.12μg/L, and the measurement result of molybdenum is (44.8±2.12)μg/L. The measurement result of 19 elements in human urine ranges from less than the detection limit to 601μg/L, and the extended uncertainty range is 0.38~33.6μg/L.Conclusion It was found from the calculation that the uncertainty of the determination result was mainly affected by the uncertainty of the sample repeated measurement and the standard curve fitting. By adjusting the range of standard curve and increasing the number of parallel sample measurement, the uncertainty was reduced and the quality of detection was improved.

Extracellular vesicles(EVs)are nano-sized bilayer vesicles that are shed or secreted by virtually every cell type.A variety of biomolecules,including proteins,lipids,coding and non-coding RNAs,and mitochondrial DNA,can be selectively encapsulated into EVs and delivered to nearby and distant recipient cells,leading to alterations in the recipient cells,suggesting that EVs play an important role in intercellular communication.EVs play effective roles in physiology and pathology and could be used as diagnostic and therapeutic tools.At present,although the mechanisms of exosome biogenesis and secretion in donor cells are well understood,the molecular mechanism of EV recognition and uptake by recipient cells is still unclear.This review summarizes the current understanding of the molecular mechanisms of EVs'biological journey in recipient cells,from recognition to uptake and cargo release.Furthermore,we highlight how EVs escape endolysosomal degradation after uptake and thus release cargo,which is crucial for studies applying EVs as drug-targeted delivery vehicles.Knowledge of the cellular processes that govern EV uptake is important to shed light on the functions of EVs as well as on related clinical applications.

Objective:To investigate the clinical efficacy of three-connections and four-screwings technique in the treatment of high double column acetabular fractures through a single ilioinguinal approach.Methods:A retrospective study was conducted to analyze the data of 42 patients who had been treated for high double column acetabular fractures from June 2017 to June 2020 at Trauma Ward 2, Department of Orthopedics and Traumatology, The First Hospital of Traditional Chinese Medicine of Changde. There were 19 males and 23 females with an age of (42.7±25.6) years. 29 injuries were due to a traffic accident, 12 ones to fall from a height, and one to fall. The time from injury to operation was (4.5±2.1) days. All the patients were treated by the three-connections and four-screwings technique through a single ilioinguinal approach. Briefly, the anterior column was connected and secured to the main bone using 3 routes, and the posterior column was attached and fixated to the anterior column reset using 2 or 3 of the 4 screwings. The operation time, intraoperative blood loss, fracture reduction quality, fracture healing time, hip function at the last follow-up and complications during the follow-up were recorded.Results:For this cohort, the operation time was (150.0±30.5) min, and intraoperative blood loss (300.0±50.0) mL. According to the Matta scale for postoperative acetabular fracture reduction, 34 cases were excellent, 6 cases good, and 2 cases acceptable, with an excellent and good rate of 95.2% (40/42). After operation one patient had fat liquefaction and wound exudation which responded to drainage and dressing change. The 42 patients were followed up for (15.0±3.4) months. All fractures healed after (11.0±2.0) months. By the modified Merle d'Aubigné & Postel scoring system, the hip function was evaluated at the last follow-up as excellent in 33 cases, as good in 6 cases, and as fair in 3 cases, yielding an excellent and good rate of 92.9% (39/42).Conclusions:In the treatment of high double column acetabular fractures, the three-connections and four-screwings technique through a single ilioinguinal approach can lead to fine reduction and rigid fixation by lag screw compression and neutralization plate protection. Consequently, early functional exercises can be performed to secure good therapeutic outcomes for the patients.

Objective To explore the important factors influencing organ donation willingness and coordination effect of organ donation coordinators. Methods A questionnaire survey was conducted among 349 national organ donation coordinators by convenience sampling, including 145 males and 204 females, aged 27 (23, 36) years. Multiple linear regression and disordered logistic regression were used to investigate the important factors influencing the willingness to donate organs and coordination effects. Results Among 349 organ donation coordinators, 146 (41.8%) were willing to donate organs, including 101 (28.9%) who had signed the consent card for organ donation. Adequate awareness of organ donation laws, high education level, marital experience, and good self-perceived health status all showed positive effects on organ donation willingness of organ donation coordinators (all P < 0.05). High income, long length of service as organ donation coordinators, full-time mode of employment, high willingness to donate organs, and adequate awareness of donation conditions and donation procedures all showed positive effects on the coordination effect of organ donation coordinators (all P < 0.05). Conclusions The willingness to donate organs is increased as the higher awareness of organ donation laws of organ donation coordinators, while enhancing the willingness to donate organs of organ donation coordinators exerts positive impact upon improving the coordination effect of organ donation coordination. Therefore, an all-round organ donation coordinator training system should be established to improve the success rate of organ donation advocacy and promote the development of organ donation.

Objective:To evaluate balloon compression-assisted endoscopic injection sclerotherapy (bc-EIS) for the treatment of esophageal varices.Methods:From June 2019 to November 2020, cirrhotic patients with esophageal varices who received endoscopic injection sclerotherapy (EIS) in the First Affiliated Hospital of Anhui Medical University were enrolled in the study. The patients were randomly divided into the bc-EIS group and the traditional EIS group. The number of treatments to eradicate varicose veins, the dose of sclerosing agent used in the first treatment, the number of injection points in the first treatment, the rebleeding rate within 10 months after the operation and the incidence of complications or adverse reactions were compared between the two groups.Results:Ninety-two cases were initially included in the study, and 7 cases were excluded based on exclusion criteria. Finally, 85 cases were included in the data analysis, 47 in the bc-EIS group and 38 in the traditional EIS group. The first eradication rate, the second cumulative eradication rate and the third cumulative eradication rate were 82.98% (39/47), 91.49% (43/47) and 100.00% (47/47) in the bc-EIS group, and they were 10.53% (4/38) ( χ 2=44.125, P<0.001), 31.58% (12/38) ( χ 2=33.023, P<0.001) and 63.16% (24/38) ( χ 2=20.730, P<0.001), respectively in the traditional EIS group, and the differences were statistically significant. The treatment times of eradicating varicose veins in the bc-EIS group and the traditional EIS group were 1.25±0.60 and 3.21±1.41, respectively, with significant difference. The dosage of sclerosing agent in first treatment in the bc-EIS group and the traditional EIS group was 17.66±7.14 mL and 22.92±6.84 mL, respectively ( t=3.441, P=0.001). The numbers of initial injection points in the bc-EIS group and the traditional EIS group were 2.70±0.86 and 2.78±1.04, respectively and the difference was not statistically significant ( t=1.847, P=0.065). The rebleeding rates of the two groups within 10 months after the operation were 2.13% (1/47) and 18.42% (7/38) respectively ( χ 2=4.771, P=0.029). There were no serious complications in the two groups. The incidences of retrosternal pain, nausea and vomiting, abdominal distension and ulcer were 2.13% (1/47), 2.13% (1/47), 4.26% (2/47) and 0.00% (0/47) in the bc-EIS group, and in the traditional EIS group, they were 5.26% (2/38) ( χ 2=0.035, P=0.851), 5.26% (2/38) ( χ 2=0.035, P=0.851), 7.89% (3/38) ( χ 2=0.060, P=0.806) and 7.89% (3/38) ( χ 2=1.877, P=0.171), respectively, without significant difference. Conclusion:Bc-EIS is more effective than traditional EIS for the treatment of esophageal varices with lower postoperative rebleeding rate, which shows better clinical application value.

OBJECTIVE To investigate the effect and mechanism of Poria cocos polysaccharides on the regulation of blood glucose in type 2 diabetes mellitus （T2DM）model rats by phosphatidylinositol 3-kinase（PI3K）/protein kinase B （Akt）/forked box transcription factor O 1（FoxO1）pathway. METHODS SD rats were randomly divided into blank control group （no modeling ，no administration），model group （modeling，no administration ），metformin group （modeling，200 mg/kg）and P. cocos polysaccharide low-dose，medium-dose and high-dose groups （modeling，100，200，400 mg/kg），8 in each group. Except for blank control group ， other groups were given high fat diet combined with streptozotocin to construct the model of T 2DM rats. At the same time ， administration groups were given relevant dose of medicine intragastrically ，and blank control group and model group were given constant volume of water intragastrically ，once a day ，for consecutive 42 days. During the experiment ，general condition and bodyweight of rats were observed every day ；fasting blood glucose （FBG）of rats were collected ，and oral glucose tolerance test were conducted and area under curve （AUC）was calculated the day before last administration. After last medication ，the heart ，liver， kidney organ index were calculated ；the levels of HbA 1c，TC，TG，MDA，SOD，GSH-Px and hepatic glycogen content were detected. HE staining was used to observe the pathological changes of liver and pancreatic tissue ，and the pathological grade score was calculated. Western blot assay was used to detect the protein expressions of p-PI 3K，p-Akt，p-FoxO1， PEPCK and G 6Pase in liver tissues. RESULTS Compared with blank control group ，the rats of model group suffered cc1965@163.com from polydipsia ，polyphagia and polyuria ；the body weight ， the levels of SOD and GSH-Px ，the protein expressions of p-PI 3K，p-Akt and p-FoxO 1 were significantly decreased （P＜0.05）；liver and kidney organ index ，blood glucose level at 0，0.5 and 2 hours after intragastric administration of glucose solution ，AUC， FBG，HbA1c，serum levels of MDA ，TC，TG and hepatic glycogen content ，liver and pancreatic pathological grade score ，the protein expressions of PEPCK and G 6Pase were all increased significantly （P＜0.05）. Compared with model group ，the general condition of rats in P. cocos polysaccharide groups were all improved ，and all of above indicators had been reversed to varying degrees. CONCLUSIONS P. cocos polysaccharide can downregulate protein expressions of PEPCK and G 6Pase which are key enzymes of gluconeogenesis ，inhibit hepatic gluconeogenesis ，effectively decrease blood glucose levels and regulate glucolipid metabolism in T 2DM model rats by weakening oxidative stress and upregulating PI 3K/Akt/FoxO1 pathway.

Objective To investigate the influence of perceptions and emotional attitudes on the public's willingness to organ donation and its path of promotion. Methods The mediation effect and structural equation models were established through the convenience sampling method and with ABC attitude model as the theoretical basis to analyze the influence of perceptions and emotional attitudes on the public's willingness to organ donation and the path of promotion. Results Among 4 565 investigated subjects, 621 subjects expressly stated that they were not willing to donate their organs after the death, 701 subjects were willing to donate their organs after the death, but only 259 investigated subjects signed the informed content card of organ donation. The differences in the subjects' willingness to donate their organs were statistically significant in terms of different genders, ages, religious beliefs, places of residence and educational degrees (all P < 0.05). The overall Cronbach's α coefficient of the questionnaire was 0.781, KMO=0.842, with good reliability and validity. In the structural equation model, the path coefficient of perceptions on the willingness to donation was 0.39, while that of attitudes on the willingness was 0.25. As such, perceptions and emotional attitudes had positive impacts on the willingness to donate the organs. The results of the mediation effect model indicated that attitudes played significant mediation effects in the causality relationship of perceptions on the willingness to donate organs, and the mediation effect value was 0.035(P < 0.01). The awareness degree of organ donation was the largest determinant to the perception factor, and the path coefficient on the willingness to donation was 0.20. The sense of social honor was the largest determinant to the attitude factor, and the path coefficient was 0.16. Conclusions Both perceptions and emotional attitudes positively impact the willingness to donate organs. The awareness degree of organ donation is the largest determinant to the perception factor, while the sense of social honor is the largest determinant to the attitude factor. To improve the public's perception level towards the organ donation and increase the public's sense of social honor towards organ donation contributes to the improvement of the public's willingness to donate organs.

Objective:To investigate the clinical efficacy and safety of balloon compression-assisted endoscopic injection sclerotherapy (bc-EIS) for esophageal varices in patients with cirrhosis.Methods:From December 2020 to April 2021, cirrhotic patients with esophageal varices who planned to receive endoscopic treatment in the Department of Gastroenterology of the First Affiliated Hospital of Anhui Medical University were selected and randomly divided into the trial group (treated with bc-EIS) and the control group [treated with endoscopic variceal ligation (EVL)] through computer randomization. The varices eradication rate, rebleeding rate and postoperative adverse reactions in the two groups were studied.Results:During the study, 93 cases were initially included according to inclusion criteria, among which 9 cases were excluded by exclusion criteria. Finally, 84 cases were included for data analysis, with 42 cases in each group. The esophageal varices eradication rate after the first treatment in the trial group was 88.10% (37/42), which was significantly higher than that in the control group [33.33% (14/42)] ( χ2=26.40, P<0.001). The esophageal varices eradication rate after 1 to 2 times and 1 to 3 times of treatment in the trial group were both significantly higher than those in the control group [97.62% (41/42) VS 40.48% (17/42), χ2=29.47, P<0.001; 100.00% (42/42) VS 45.24% (19/42), P<0.001]. The maximum follow-up period was 6 months, and none of the patients had rebleeding in the trial group, and the rebleeding rate in the control group was 4.76% (2/42) ( P=0.494). The incidence of thoracic and abdominal discomfort, nausea and vomiting, and abdominal distension in the trial group and control group were 26.19% (11/42) and 35.71% (15/42) ( χ2=0.51, P=0.474), 2.38% (1/42) and 7.14% (3/42) ( χ2=0.26, P=0.608), and 4.76% (2/42) and 11.90% (5/42) ( χ2=0.62, P=0.430), respectively. No other adverse events such as infection, dysphagia, perforation, esophageal tracheal fistula, esophageal stenosis, or ectopic embolism occurred in any group. Conclusion:Bc-EIS is effective and safe for the treatment of esophageal varices in patients with cirrhosis, with a one-time varices eradication rate of more than 85%, and can be completely eradicated after 1 to 3 times of treatment.

Objective To establish an evaluation method of uncertainty for the determination of lead in ambient air PM_2.5 by inductively coupled plasma mass spectrometry (ICP-MS). Methods According to HJ657-2013 ^“Determination of Lead and Other Metal Elements in Air and Exhaust Particulates by Inductively Coupled Plasma Mass Spectrometry^”, the concentration of lead in ambient air PM2.5 was determined. A mathematical model was established to analyze the source of uncertainty and to calculate each component of uncertainty. The components were combined into the standard uncertainty, and the relative expanded uncertainty was finally obtained. Results The expanded uncertainty of lead in ambient air PM2.5 was 0.16 ng/m³, and the measurement result of lead was (1.75±0.16)ng/m³. Conclusion The main source of uncertainty of this method comes from the relative standard uncertainty introduced by sample pretreatment.

New threats posed by the emerging circulating variants of SARS-CoV-2 highlight the need to find conserved neutralizing epitopes for therapeutic antibodies and efficient vaccine design. Here, we identified a receptor-binding domain (RBD)-binding antibody, XG014, which potently neutralizes β-coronavirus lineage B (β-CoV-B), including SARS-CoV-2, its circulating variants, SARS-CoV and bat SARSr-CoV WIV1. Interestingly, antibody family members competing with XG014 binding show reduced levels of cross-reactivity and induce antibody-dependent SARS-CoV-2 spike (S) protein-mediated cell-cell fusion, suggesting a unique mode of recognition by XG014. Structural analyses reveal that XG014 recognizes a conserved epitope outside the ACE2 binding site and completely locks RBD in the non-functional "down" conformation, while its family member XG005 directly competes with ACE2 binding and position the RBD "up". Single administration of XG014 is effective in protection against and therapy of SARS-CoV-2 infection in vivo. Our findings suggest the potential to develop XG014 as pan-β-CoV-B therapeutics and the importance of the XG014 conserved antigenic epitope for designing broadly protective vaccines against β-CoV-B and newly emerging SARS-CoV-2 variants of concern.
Angiotensin-Converting Enzyme 2 ; Antibodies, Neutralizing ; Antibodies, Viral ; COVID-19 ; Epitopes ; Humans ; SARS-CoV-2/genetics* ; Spike Glycoprotein, Coronavirus/genetics*