Objective:To investigate the effects of 10° head up tilt bed rest (HUT) on human cardiac function via 3D speckle tracking echocardiography (3D-STE), and to study the difference in cardiac function under the submaximal exercise load between the horizontal position and 10° HUBR.Methods:Thirty young healthy volunteers were recruited as the subjects, who were randomly divided into an 10° HUT exercise group and horizontal exercise group with 15 subjects in each. Subjects in both groups were asked to ride the bicycle ergometer in the 10° HUBR position and supine position respectively. The load started with 50 W and was increased by 25 W every 3 min until it reached the maximum of 125 W. Before the exercise (resting state), 1 min after the load was increased each time, and 3 min after exercise (recovery period), the following indices were collected: ①basic cardiac function indices: heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP), ②conventional cardiac ultrasound indices: left ventricular ejection fraction (LVEF), stroke volume (SV) and cardiac output (CO), ③left ventricular strain indices: global longitudinal strain (GLS), global circumferential strain (GCS), and global area strain (GAS) measured by 3D-SET. The changes of these indices in the 2 groups of subjects under different exercise loads were observed.Results:The differences in the major effect of the basic heart indices (HR, SBP and DBP), conventional cardiac ultrasound indices (LVEF, SV and CO) and left ventricular strain indices (GLS, GCS and GAS) in response to the exercise load were statistically significant ( F=194.90, 113.66, 17.19, P=0.017, 0.018, 0.001). With the increase of the exercise load, the basic heart indices and conventional cardiac ultrasound indices kept rising, the left ventricular strain indices reached the minimum under a moderate exercise load (75 W), HR, SBP and CO were higher than those of the resting state ( P<0.05 or 0.01). Both LVEF under exercise loads of 75, 100, 125 W and during recovery, and SV under exercise loads of 100, 125 W and during recovery were significantly higher than those of the resting state ( P<0.05 or 0.01), while GLS and GCS under exercise loads of 50, 75, 125 W ( P<0.05 or 0.01), and GAS under exercise loads of 50, 75 W ( P<0.01) were significantly lower. There were statistically significant differences not only in GCS across the groups ( F=4.60, P=0.026) but also in DBP due to the interactions between the grouping and exercise loads ( F=3.13, P=0.031). DBP was higher than that of the resting state when the exercise load was 125 W in both groups. Conclusions:During submaximal exercise, myocardial contractility shows sustained enhancement with the increase of the exercise load. The results of GLS, GCS and GAS indicate that myocardial strain reaches its lowest value under a moderate exercise load, suggesting that moderate exercise can be used to evaluate cardiac function via 3D-SET. Under a simulated lunar gravity of 10° HUT, there is less deformation in the short axis direction of the myocardium, indicating that GCS can be used as a sensitive indicator to detect changes in cardiac function under different gravities.

Objective To investigate the application effect of cold snare endoscopic mucosal resection(CS-EMR)in the treatment of 6 to 9 mm colorectal small polyps.Methods A total of 82 patients with small colonic polyps in our hospital from March 2022 to August 2023 were collected and divided into the observation group(45 cases received CS-EMR)and the control group[37 cases received hot snare endoscopic mucosal resection(HS-EMR)]according to different surgical methods.The clinical efficacy,polyp resection status,complete polyp resection rate,perioperative indicators and occurrence of complications were compared between the two groups.Results Follow-up for 1 month after operation,the effective rate of treatment in the observation group was higher than that in the control group(P<0.05).There was no statistically significant difference in the polyp resection status or perioperative indicators between the two groups(P>0.05).There was no statistically significant difference in the complete polyp resection rates of patients with different pathological types or total complete resection rate between the two groups(P>0.05).The incidence of delayed bleeding and endoscopic hemostasis rate in the observation group were lower than those in the control group(P<0.05).Conclusion The complete resection rate of 6～9 mm colorectal polyps through CS-EMR was comparable to that of HS-EMR,and CS-EMR has a better efficacy and lower risk of perioperative bleeding,along with higher safety.

Objective To investigate the application effect of cold snare endoscopic mucosal resection(CS-EMR)in the treatment of 6 to 9 mm colorectal small polyps.Methods A total of 82 patients with small colonic polyps in our hospital from March 2022 to August 2023 were collected and divided into the observation group(45 cases received CS-EMR)and the control group[37 cases received hot snare endoscopic mucosal resection(HS-EMR)]according to different surgical methods.The clinical efficacy,polyp resection status,complete polyp resection rate,perioperative indicators and occurrence of complications were compared between the two groups.Results Follow-up for 1 month after operation,the effective rate of treatment in the observation group was higher than that in the control group(P<0.05).There was no statistically significant difference in the polyp resection status or perioperative indicators between the two groups(P>0.05).There was no statistically significant difference in the complete polyp resection rates of patients with different pathological types or total complete resection rate between the two groups(P>0.05).The incidence of delayed bleeding and endoscopic hemostasis rate in the observation group were lower than those in the control group(P<0.05).Conclusion The complete resection rate of 6～9 mm colorectal polyps through CS-EMR was comparable to that of HS-EMR,and CS-EMR has a better efficacy and lower risk of perioperative bleeding,along with higher safety.

Objective:To investigate the effects of 10° head up tilt bed rest (HUT) on human cardiac function via 3D speckle tracking echocardiography (3D-STE), and to study the difference in cardiac function under the submaximal exercise load between the horizontal position and 10° HUBR.Methods:Thirty young healthy volunteers were recruited as the subjects, who were randomly divided into an 10° HUT exercise group and horizontal exercise group with 15 subjects in each. Subjects in both groups were asked to ride the bicycle ergometer in the 10° HUBR position and supine position respectively. The load started with 50 W and was increased by 25 W every 3 min until it reached the maximum of 125 W. Before the exercise (resting state), 1 min after the load was increased each time, and 3 min after exercise (recovery period), the following indices were collected: ①basic cardiac function indices: heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP), ②conventional cardiac ultrasound indices: left ventricular ejection fraction (LVEF), stroke volume (SV) and cardiac output (CO), ③left ventricular strain indices: global longitudinal strain (GLS), global circumferential strain (GCS), and global area strain (GAS) measured by 3D-SET. The changes of these indices in the 2 groups of subjects under different exercise loads were observed.Results:The differences in the major effect of the basic heart indices (HR, SBP and DBP), conventional cardiac ultrasound indices (LVEF, SV and CO) and left ventricular strain indices (GLS, GCS and GAS) in response to the exercise load were statistically significant ( F=194.90, 113.66, 17.19, P=0.017, 0.018, 0.001). With the increase of the exercise load, the basic heart indices and conventional cardiac ultrasound indices kept rising, the left ventricular strain indices reached the minimum under a moderate exercise load (75 W), HR, SBP and CO were higher than those of the resting state ( P<0.05 or 0.01). Both LVEF under exercise loads of 75, 100, 125 W and during recovery, and SV under exercise loads of 100, 125 W and during recovery were significantly higher than those of the resting state ( P<0.05 or 0.01), while GLS and GCS under exercise loads of 50, 75, 125 W ( P<0.05 or 0.01), and GAS under exercise loads of 50, 75 W ( P<0.01) were significantly lower. There were statistically significant differences not only in GCS across the groups ( F=4.60, P=0.026) but also in DBP due to the interactions between the grouping and exercise loads ( F=3.13, P=0.031). DBP was higher than that of the resting state when the exercise load was 125 W in both groups. Conclusions:During submaximal exercise, myocardial contractility shows sustained enhancement with the increase of the exercise load. The results of GLS, GCS and GAS indicate that myocardial strain reaches its lowest value under a moderate exercise load, suggesting that moderate exercise can be used to evaluate cardiac function via 3D-SET. Under a simulated lunar gravity of 10° HUT, there is less deformation in the short axis direction of the myocardium, indicating that GCS can be used as a sensitive indicator to detect changes in cardiac function under different gravities.

Objective Viral encephalitis is an infectious disease severely affecting human health.It is caused by a wide variety of viral pathogens,including herpes viruses,flaviviruses,enteroviruses,and other viruses.The laboratory diagnosis of viral encephalitis is a worldwide challenge.Recently,high-throughput sequencing technology has provided new tools for diagnosing central nervous system infections.Thus,In this study,we established a multipathogen detection platform for viral encephalitis based on amplicon sequencing. Methods We designed nine pairs of specific polymerase chain reaction(PCR)primers for the 12 viruses by reviewing the relevant literature.The detection ability of the primers was verified by software simulation and the detection of known positive samples.Amplicon sequencing was used to validate the samples,and consistency was compared with Sanger sequencing. Results The results showed that the target sequences of various pathogens were obtained at a coverage depth level greater than 20×,and the sequence lengths were consistent with the sizes of the predicted amplicons.The sequences were verified using the National Center for Biotechnology Information BLAST,and all results were consistent with the results of Sanger sequencing. Conclusion Amplicon-based high-throughput sequencing technology is feasible as a supplementary method for the pathogenic detection of viral encephalitis.It is also a useful tool for the high-volume screening of clinical samples.

Objective To investigate the infection status and changing trend of hepatitis C virus(HCV)infection in hospitalized patients in medical institutions,and provide reference for formulating HCV infection prevention and control strategies.Methods HCV infection surveillance results from cross-sectional survey data reported to China Healthcare-associated Infection(HAI)Surveillance System in 2020 were summarized and analyzed,HCV positive was serum anti-HCV positive or HCV RNA positive,survey result was compared with the survey results from 2003.Results In 2020,1 071 368 inpatients in 1 573 hospitals were surveyed,738 535 of whom underwent HCV test,4 014 patients were infected with HCV,with a detection rate of 68.93％and a HCV positive rate of 0.54％.The positive rate of HCV in male and female patients were 0.60％and 0.48％,respectively,with a statistically sig-nificant difference(x2=47.18,P＜0.001).The HCV positive rate in the 50-＜60 age group was the highest(0.76％),followed by the 40-＜50 age group(0.71％).Difference among all age groups was statistically signifi-cant(x2=696.74,P＜0.001).In 2003,91 113 inpatients were surveyed.35 145 of whom underwent HCV test,resulting in a detection rate of 38.57％;775 patients were infected with HCV,with a positive rate of 2.21％.In 2020,HCV positive rates in hospitals of different scales were 0.46％-0.63％,with the highest in hospital with bed numbers ranging 600-899.Patients'HCV positive rates in hospitals of different scales was statistically signifi-cant(X2=35.34,P＜0.001).In 2020,12 provinces/municipalities had over 10 000 patients underwent HCV-rela-ted test,and HCV positive rates ranged 0.19％-0.81％,with the highest rate from Hainan Province.HCV posi-tive rates in different departments were 0.06％-0.82％,with the lowest positive rate in the department of pedia-trics and the highest in the department of internal medicine.In 2003 and 2020,HCV positive rates in the depart-ment of infectious diseases were the highest,being 7.95％and 3.48％,respectively.Followed by departments of orthopedics(7.72％),gastroenterology(3.77％),nephrology(3.57％)and general intensive care unit(ICU,3.10％)in 2003,as well as departments of gastroenterology(1.35％),nephrology(1.18％),endocrinology(0.91％),and general intensive care unit(ICU,0.79％)in 2020.Conclusion Compared with 2003,HCV positive rate decreased significantly in 2020.HCV infected patients were mainly from the department of infectious diseases,followed by departments of gastroenterology,nephrology and general ICU.HCV infection positive rate varies with gender,age,and region.

AIM:To observe the changes of photopic negative response(PhNR)of multifocal electroretinogram(mf-ERG)in patients with diabetic macular edema(DME)before and after treatment with Aflibercept.METHODS: A total of 37 patients(37 eyes)with DME who visited the Aier Eye Hospital of Wuhan University(Wuhan Aier Eye Hospital)from May 2019 to June 2022, and 0.05 mL of aflibercept was injected per month for consecutive 3mo were included in this retrospective cohort study. Another 20 cases(20 eyes)with normal physical examination to exclude related eye diseases were selected as the control group. The PhNR amplitude of mf-ERG, best-corrected visual acuity(BCVA; LogMAR), central retinal thickness(CRT), capillary plexus in macular area and vessel density(CPVD)of the participants between the two groups were compared before and after treatment.RESULTS: The PhNR amplitude of mf-ERG in DME patients before treatment(201.69±80.92nV)was significantly lower than that in the normal control group(398.87±77.92nV; P<0.01), and the average PhNR amplitude of mf-ERG in DME patients at 6mo after treatment was significantly higher than that before treatment(P=0.036), but it was still significantly lower than the normal control group at 6mo after treatment(P=0.031). In addition, the BCVA(LogMAR)of DME patients increased from 0.64±1.33 to 0.37±1.39(P=0.021)at 6mo after treatment, and CPVD significantly increased compared to that before treatment(P=0.029). Meanwhile, the PhNR amplitude of mf-ERG in DME patients at 6mo after treatment was positively correlated with CPVD at 6mo after treatment(r=0.448, P=0.043), and negatively correlated with BCVA(LogMAR)and CRT(r=-0.647, P=0.011; r=-0.337, P=0.032).CONCLUSION: The PhNR amplitude of mf-ERG in DME patients increased significantly after receiving aflibercept, and it can be used to observe and evaluate the functional changes of retinal ganglion cells in DME patients.

Objective:To provide references for achieving long time continuous monitoring of cardiac functional changes of astronauts in spaceflight activities through continuously noninvasive assessment of left ventricular systolic function under exercise load by wearable cardiac sounds and ECG signals synchronization monitoring technology.Methods:Eleven healthy male youths were recruited for the study, and they did incremental load exercise on the recumbent power bicycle, starting at 50 W, increasing by 25 W every 3 minutes, until the maximum of 125 W reached. The subjects′ cardiac sounds and ECG signals at rest, 1 min after each level of load during exercise and 3 min after the end of exercise were selected; the transthoracic cardiac ultrasound examination of subjects was performed before and 5 min after exercise. The correlation between the cardiac sounds and ECG signals and left ventricular ejection fraction (LVEF) was analyzed, and a regression model was established to predict LVEF during exercise.Results:There were significant differences in heart rate, LVEF, electro-mechanical activation time (EMAT) and left ventricular ejection time (LVET) of subjects under different exercise loads ( F=53.22, 45.33, 3.65, 23.19, P<0.001, <0.001, =0.011, <0.001). Compared with the resting state, subjects showed increased heart rate and LVEF and a decreased EMAT and LVET during exercise loading, all of which were statistically significant ( P<0.01 or 0.05). In the correlation analysis, LVEF was negatively correlated with EMAT and LVEF ( r=-0.415, -0.758, P=0.002,<0.001), and positively correlated with the amplitude of the first heart sound ( r=0.606, P<0.001). The model for predicting LVEF was established by EMAT and LVET, and the multiple regression model was LVEF=108.698-0.092×LVET-0.134×EMAT ( r=0.87, P<0.001). Conclusions:The synchronous monitoring technology of cardiac sounds and ECG signals can continuously and non-invasively monitor LVEF changes during exercise. LVET is the most closely related to LVEF. LVEF is hopeful to predict the changes of cardiac function of astronauts in spaceflight activities.

Objective:To provide references for achieving long time continuous monitoring of cardiac functional changes of astronauts in spaceflight activities through continuously noninvasive assessment of left ventricular systolic function under exercise load by wearable cardiac sounds and ECG signals synchronization monitoring technology.Methods:Eleven healthy male youths were recruited for the study, and they did incremental load exercise on the recumbent power bicycle, starting at 50 W, increasing by 25 W every 3 minutes, until the maximum of 125 W reached. The subjects′ cardiac sounds and ECG signals at rest, 1 min after each level of load during exercise and 3 min after the end of exercise were selected; the transthoracic cardiac ultrasound examination of subjects was performed before and 5 min after exercise. The correlation between the cardiac sounds and ECG signals and left ventricular ejection fraction (LVEF) was analyzed, and a regression model was established to predict LVEF during exercise.Results:There were significant differences in heart rate, LVEF, electro-mechanical activation time (EMAT) and left ventricular ejection time (LVET) of subjects under different exercise loads ( F=53.22, 45.33, 3.65, 23.19, P<0.001, <0.001, =0.011, <0.001). Compared with the resting state, subjects showed increased heart rate and LVEF and a decreased EMAT and LVET during exercise loading, all of which were statistically significant ( P<0.01 or 0.05). In the correlation analysis, LVEF was negatively correlated with EMAT and LVEF ( r=-0.415, -0.758, P=0.002,<0.001), and positively correlated with the amplitude of the first heart sound ( r=0.606, P<0.001). The model for predicting LVEF was established by EMAT and LVET, and the multiple regression model was LVEF=108.698-0.092×LVET-0.134×EMAT ( r=0.87, P<0.001). Conclusions:The synchronous monitoring technology of cardiac sounds and ECG signals can continuously and non-invasively monitor LVEF changes during exercise. LVET is the most closely related to LVEF. LVEF is hopeful to predict the changes of cardiac function of astronauts in spaceflight activities.

Purpose: This study aimed to identify prognostic factors for patients with distant lymph node-involved gastric cancer (GC) using a machine learning algorithm, a method that offers considerable advantages and new prospects for high-dimensional biomedical data exploration. Materials and Methods: This study employed 79 features of clinical pathology, laboratory tests, and therapeutic details from 289 GC patients whose distant lymphadenopathy was presented as the first episode of recurrence or metastasis. Outcomes were measured as anycause death events and survival months after distant lymph node metastasis. A prediction model was built based on possible outcome predictors using a random survival forest algorithm and confirmed by 5×5 nested cross-validation. The effects of single variables were interpreted using partial dependence plots. A contour plot was used to visually represent survival prediction based on 2 predictive features. Results: The median survival time of patients with GC with distant nodal metastasis was 9.2 months. The optimal model incorporated the prealbumin level and the prothrombin time (PT), and yielded a prediction error of 0.353. The inclusion of other variables resulted in poorer model performance. Patients with higher serum prealbumin levels or shorter PTs had a significantly better prognosis. The predicted one-year survival rate was stratified and illustrated as a contour plot based on the combined effect the prealbumin level and the PT. Conclusions Machine learning is useful for identifying the important determinants of cancer survival using high-dimensional datasets. The prealbumin level and the PT on distant lymph node metastasis are the 2 most crucial factors in predicting the subsequent survival time of advanced GC.Trial Registration: ChiCTR Identifier: ChiCTR1800019978