Objective This study aimed to investigate the tumorigenic properties of MMTV-PyMT breast cancer transgenic mice at different ages(in weeks)and the changes in the composition of immune cells in the tumor microenvironment.Methods Eight groups of 4,6,8,10,12,14,16 and 18 weeks of age MMTV-PyMT female mice(FVB mice as the background)and one group of 8 weeks of FVB female mice were prepared for routine blood testing,the pathological changes of the mammary gland and lung metastases were observed by histopathological sections,and the immune cells in blood,spleen,and tumor were analyzed by flow cytometry.Results MMTV-PyMT mice showed adenular ductal lesions at 4～6 weeks of age;the ductal portion expanded to the growth boundary at 8～9 weeks of age,and then gradually broke through the glandular boundary to form early breast cancer at 8～12 weeks of age,and advanced breast cancer at 10～14 weeks of age.At 12 weeks of age,metastases were visible in the lungs of some mice,and at 14 weeks of age,the number of metastases in the lungs increased significantly.As the age of the mice increased,the number of white blood cells,neutrophils,and platelets in their blood increased gradually,while the lymphocytes and erythrocytes showed a gradual downward trend.Flow cytometry showed that with the increase in age,the proportion of T cells in the spleen and tumor gradually decreased,the MDSCs in the blood,spleen,and tumor gradually increased,and the NK cells in the tumor also gradually increased.Conclusions This study analyzed routine blood tests,pathology,and immune cells in the tissues of MMTV-PyMT mouse models of different weeks of age,providing a novel perspective on the dynamic alterations of the tumor immune microenvironment during the malignant progression of breast cancer.

Objective This study aimed to investigate the tumorigenic properties of MMTV-PyMT breast cancer transgenic mice at different ages(in weeks)and the changes in the composition of immune cells in the tumor microenvironment.Methods Eight groups of 4,6,8,10,12,14,16 and 18 weeks of age MMTV-PyMT female mice(FVB mice as the background)and one group of 8 weeks of FVB female mice were prepared for routine blood testing,the pathological changes of the mammary gland and lung metastases were observed by histopathological sections,and the immune cells in blood,spleen,and tumor were analyzed by flow cytometry.Results MMTV-PyMT mice showed adenular ductal lesions at 4～6 weeks of age;the ductal portion expanded to the growth boundary at 8～9 weeks of age,and then gradually broke through the glandular boundary to form early breast cancer at 8～12 weeks of age,and advanced breast cancer at 10～14 weeks of age.At 12 weeks of age,metastases were visible in the lungs of some mice,and at 14 weeks of age,the number of metastases in the lungs increased significantly.As the age of the mice increased,the number of white blood cells,neutrophils,and platelets in their blood increased gradually,while the lymphocytes and erythrocytes showed a gradual downward trend.Flow cytometry showed that with the increase in age,the proportion of T cells in the spleen and tumor gradually decreased,the MDSCs in the blood,spleen,and tumor gradually increased,and the NK cells in the tumor also gradually increased.Conclusions This study analyzed routine blood tests,pathology,and immune cells in the tissues of MMTV-PyMT mouse models of different weeks of age,providing a novel perspective on the dynamic alterations of the tumor immune microenvironment during the malignant progression of breast cancer.

Objective To evaluate the clinical utility of the f-wave to QRS complex amplitude ratio(f/R ratio)in intracardiac electrogram(IC-ECG)-guided positioning of peripherally inserted central catheter(PICC)tips in patients with atrial fibrillation(AF),providing evidence to enhance clinical practice.Methods This study employed a conve-nience sampling method to enroll eligible AF patients admitted to a tertiary hospital in Suzhou from July 2023 to July 2024.During PICC placement,IC-ECG was utilized to monitor f-wave and QRS complex amplitude variations.Following successful catheterization,the f/R ratio was measured,and chest X-ray was performed to confirm the catheter tip position.The accuracy of PICC tip positioning across different f/R ratio ranges was analyzed,and the incidence of arrhythmias was recorded.A receiver operating characteristic curve was constructed to assess the diag-nostic performance of the f/R ratio in PICC tip localization.Results A total of 68 AF patients were included,with f/R ratios ranging from 20.63％to 91.24％.PICC tip positioning accuracy varied significantly across different f/R ratio ranges(P=0.006).The area under the ROC curve(AUC)for f/R ratio in PICC tip positioning was 0.784(P=0.009),with a maximum Youden index of 0.567,an optimal diagnostic threshold of 40.00％,a sensitivity of 81.7％,a speci-ficity of 75.0％,a positive predictive value of 96.1％,and a negative predictive value of 35.3％.No arrhythmias other than AF occurred during the procedure.Conclusion The f/R ratio provides reliable and safe guidance for PICC tip positioning in AF patients.An f/R ratio ≥40％is associated with higher accuracy in identifying the optimal catheter tip position.

Objective To evaluate the clinical utility of the f-wave to QRS complex amplitude ratio(f/R ratio)in intracardiac electrogram(IC-ECG)-guided positioning of peripherally inserted central catheter(PICC)tips in patients with atrial fibrillation(AF),providing evidence to enhance clinical practice.Methods This study employed a conve-nience sampling method to enroll eligible AF patients admitted to a tertiary hospital in Suzhou from July 2023 to July 2024.During PICC placement,IC-ECG was utilized to monitor f-wave and QRS complex amplitude variations.Following successful catheterization,the f/R ratio was measured,and chest X-ray was performed to confirm the catheter tip position.The accuracy of PICC tip positioning across different f/R ratio ranges was analyzed,and the incidence of arrhythmias was recorded.A receiver operating characteristic curve was constructed to assess the diag-nostic performance of the f/R ratio in PICC tip localization.Results A total of 68 AF patients were included,with f/R ratios ranging from 20.63％to 91.24％.PICC tip positioning accuracy varied significantly across different f/R ratio ranges(P=0.006).The area under the ROC curve(AUC)for f/R ratio in PICC tip positioning was 0.784(P=0.009),with a maximum Youden index of 0.567,an optimal diagnostic threshold of 40.00％,a sensitivity of 81.7％,a speci-ficity of 75.0％,a positive predictive value of 96.1％,and a negative predictive value of 35.3％.No arrhythmias other than AF occurred during the procedure.Conclusion The f/R ratio provides reliable and safe guidance for PICC tip positioning in AF patients.An f/R ratio ≥40％is associated with higher accuracy in identifying the optimal catheter tip position.

Objective:To summarize the imaging presentations of the fallopian canal cerebrospinal fluid leaking (FCCFL).Methods:The high resolution CT (HRCT)and MRI materials of 4 patients (4 ears) with FCCFL confirmed by surgery between August 2016 to November 2023 were retrospectively analyzed. Among these, there were 2 males and 2 females, their ages ranged from 6 to 69 years.Results:All of the FCCFL were unilateral, including 2 on the left and 2 on the right.Clinically, the patients with FCCFL suffered from clear nasal fluid flow, ear tightness, and hearing loss. On CT, all of the affected ears were depicted markedly dilatation of the proximal portion of fallopian canal(FC), the labyrinthine segment and geniculate fossa were involved in 4 cases, and involvement of tympanic segment in 1 case at the same time. The geniculate fossa in the affected side were significantly enlarged, protruding upwards into the tympanic cavity, with one case simultaneously involving the cochlea. On MRI, the hyposignal on T 1WI and hypersignal on T 2WI or water sequence like cerebrospinal fluid (CSF) were shown in the enlargement FC, without diffusion restriction, and non-enhancing with administration Gadolinium contrast.CSF-like signal effusion was shown in all of the affected tympanum, of which, the CSF-like signal effusion was demonstrated in the area along the superficial petrosal nerve, the right pterygopalatine fossa and the parapharyngeal space. The adjacent intracranial meninges were presented thickening in 3 cases. Conclusion:The imaging appearances of FCCFL present some characteristics:on HRCT, the proximal portions of the affected FC depicts markedly enlargement,especially the geniculate fossa.While they present CSF-like signal, no diffusion restriction, and no enhancement administration, Gadolinium contrast on MRI, accompanying the CSF-like signal effusion in the affected tympanum.

Objective:To summarize the HRCT and MRI appearances of stapical footplate fistula related to inner ear malformation (SFF-Re-IEM).Methods:The HRCT and MRI materials of 48 cases (53 ears) SFF-Re-IEM were retrospectively analyzed. Among them, 25 SFF-Re-IEM ears were confirmed by surgery. Their CT and MRI findings including associated IEM type, internal auditory canal (IAC) malformation, tympanic fluid, its density and signal features, and accompanied labyrinthitis were recorded.Results:Among 48 cases (53 ears) with SFF-Re-IEM, 17 ears with incomplete partition type Ⅰ, accounting for 32.1%, 13 ears with common cavity for 24.5%, 13 ears with cochlear aplasia for 24.5%, 7 ears with cochlear dysplasia Ⅱ for 13.2%, and 3 ears with Mondini for 5.7%,were found respectively. 94.3% of them were associated with a defect or dysplasia in the found of the IAC. They were divided into 4 types according to the intact of the stapical footplate and accompanied CSF otorrhea: 22 ears were diagnosed as the stapical footplate leaking, of them, 2 ears might come from the stapical footplate bony defect, 6 ears were from the stapical footplate hernia. 1 ear belonged to the peristapical footplate leaking. 30 ears with the isolated the stapical footplate hernia were another found. The bony defect in 2 ears with the stapical footplate bony defect were not presented on CT and MRI.The focal bony defect of the affected stapical footplate of 36 ears with the stapical footplate hernia were demonstrated, which presented the hemispherical protruding into the tympana, the soft-tissue density on CT, and CSF-like signal on the MR heaved-T2WI images. Among 22 ears with the stapical footplate leaking, their imaging appearances varied from the different amount of the leaking CSF. Besides the focal bony defects of the affected stapical footplates, there were much more CSF-like density or signal in the ipsilateral tympanic cavity in 17 affected ears connecting with the vestibule through the defect area. In the CSF leaking ears with less CSF leaking in 5 ears, the CSF-like cysts like SFH were shown on the stapical footplate defect area, but their outer edges were irregular, and the CSF-like signal scattering in the tympanic cavity did not connect with the protruding cysts at the stapical area.Conclusion:The variable appearances of the SFF-Re-IEM ears based on the different subtypes are its characteristic HRCT and MRI appearances. This is helpful for the SFF-Re-IEM diagnosing to grasp its imaging features.

Objective:To provide theoretical basis for strength and endurance training of waist and abdominal muscles and prevention of waist injuries in fighter pilots by exploring the muscle strength and work characteristics of the waist and abdominal flexor and extensor muscles in fighter pilots.Methods:Sixty male fighter pilots who were qualified for flight in aeromedical assessment, aged 24-46 years old, were randomly selected and divided into 24-30, 31-40, 41-46 years group. The Isomed2000 isokinetic dynamometer system was applied to measure the muscle strength and work performance of the abdominal and lumbar flexors and extensors of the fighter pilots with the angular velocities of 60°/s and 180°/s. The flexion and extension muscle peak torque, relative peak torque, flexion-extension ratio, and endurance ratio were compared among different age groups of pilots.Results:At the same angular velocity, the peak torque and relative peak torque of the lumbar and abdominal extensor muscles in fighter pilots were greater than those of the flexor muscles, with statistically significant differences ( t=7.01-9.13, all P<0.001). The peak torque and relative peak torque of the lumbar and abdominal flexor and extensor muscles significantly decreased with increasing test angular velocity ( t=13.63-17.25, all P<0.001). Under the angular velocity of 60°/s, there were no significant differences in the peak torque and relative peak torque of the flexor muscles among different age groups (both P>0.05); there were significant differences in the peak torque and relative peak torque of extensor muscles ( F=5.31, 6.61, P=0.008, 0.003) and 41-46 years groups were lower than the other 2 groups ( P=0.019, 0.003, 0.002, 0.004). Under an angular velocity of 180°/s, there were significant differences in the peak torque and relative peak torque of the waist and abdominal flexor and extensor muscles among different age groups ( F=3.82, 3.47, 3.83, 5.49, P=0.028, 0.043, 0.027, 0.008); the relative peak torque of the abdominal and lumbar flexor and extensor muscles in the 24-30 years group was higher than that in the 41-46 years group ( P=0.032, 0.006). The peak torque and the relative peak torque of the abdominal and lumbar flexor muscles in 31-40 years group were higher than those in 41-46 years group ( P=0.008, 0.013). The low qualification rate of peak torque ratio indicated the imbalance between flexor and extensor muscles and the poor endurance of abdominal and lumbar flexor and extensor muscles than that of flexor muscles. There was no statistically significant difference in the endurance ratio of the abdominal and lumbar flexor and extensor muscles among different age groups ( P>0.05). Conclusions:The balance between flexor and extensor muscles of waist and abdominal muscles should be paid more in fighter pilot′s fitness training. For the pilots older than 40 the training targeted to slow the muscles decline is necessary.

Objective To investigate the relationship between cerebrovascular reserve (CVR) capacity and white matter lesions in elderly people. Methods We included 315 participants aged ≥ 60 years in Jinan area of Shandong Province from May 2018 to July 2019. They underwent transcranial Doppler ultrasonography for assessing CVR, breath holding index (BHI), and arterial pulsatility index (PI). According to CVR capacity, they were divided into normal CVR group (CVR ≥ 20%, n = 206) and impaired CVR group (CVR < 20%, n = 109). Magnetic resonance imaging was performed to evaluate periventricular, subcortical, and total white matter hyperintensity (WMH) volumes and Fazekas scores. Results Compared with the normal CVR group, the impaired CVR group showed significantly higher volumes of periventricular, subcortical, and total WMHs and significantly higher proportions of Fazekas scores ≥ 2 (P < 0.01). Periventricular, subcortical, and total WMH volumes were negatively correlated with CVR (r = −0.70, −0.66, −0.73, P < 0.01) and BHI (r = −0.64, −0.65, −0.68, P < 0.01) and positively correlated with PI (r = 0.60, 0.65, 0.65, P < 0.01). After adjusting for confounding factors, periventricular, subcortical, and total WMH volumes were still negatively correlated with CVR and BHI (P < 0.01) and positively correlated with PI (P < 0.01). The logistic regression analysis showed that the risks of periventricular, subcortical, and total Fazekas score ≥ 2 in the impaired CVR group were 1.96 times (95% confidence interval [CI]: 1.17−3.27, P < 0.01), 1.84 times (95% CI: 1.11−3.05, P < 0.05), and 2.33 times (95% CI: 1.30−4.18, P < 0.01) that of the normal CVR group, respectively. Conclusion Impaired CVR is an independent risk factor for white matter lesions in the elderly.

Objective:To explore the pathogenesis and potential biomarkers of atrial fibrillation based on bioinformatics.Methods:Differentially expressed genes and module genes related to atrial fibrillation were obtained from GSE41177 and GSE79768 datasets(Chinese-origin tissue samples)through differential expression analysis and weighted gene co-expression network analysis.Candidate hub genes were obtained by taking intersections,and hub genes were obtained after gender stratification.Subsequently,functional enrichment analysis and immune infiltration analysis were performed.Four machine learning models were constructed based on the hub genes,and the optimal model was selected to construct a prediction nomogram.The prediction ability of the nomogram was verified using calibration curves and decision curves.Finally,potential therapeutic drugs for atrial fibrillation were screened from the DGIdb database.Results:A total of 67 differentially expressed genes and 65 module genes related to atrial fibrillation were identified.Functional enrichment analysis indicated that the pathogenesis of atrial fibrillation was closely related to inflammatory response,immune response,and immune and infectious diseases.Four common hub genes(TYROBP,FCER1G,EVI2B and SOD2),and two genes specifically expressed in male(PILRA and SLC35G3)and female(HLA-DRA and GATP)patients with atrial fibrillation were obtained after gender-segregated screening.The extreme gradient boosting model had satisfactory diagnostic efficiency,and the nomogram constructed based on the hub genes,male significant variables(PILRA,SLC35G3 and SOD2),and female significant variables(FCER1G,SOD2 and TYRO BP)had satisfactory predictive ability.Immune infiltration analysis demonstrated a disturbed immune infiltration microenvironment in atrial fibrillation with a higher abundance of plasma cells,neutrophils,and γδT cells,with a higher abundance of neutrophils in males and resting mast cells in females.Two potential drugs for the treatment of atrial fibrillation,valproic acid and methotrexate,were obtained by database and literature screening.Conclusions:The pathogenesis of atrial fibrillation is closely related to inflammation and immune response,and the microenvironment of immune cell infiltration of cardiomyocytes in the atrial tissue of patients with atrial fibrillation is disordered.TYROBP,FCER1G,EVI2B and SOD2 serve as potential diagnostic biomarkers of atrial fibrillation;PILRA and SLC35G3 serve as potential specific diagnostic biomarkers of atrial fibrillation in the male population,which can effectively predict the risk of atrial fibrillation development and are also potential targets for the treatment of atrial fibrillation.

Objective To investigate the effectiveness of team-based learning(TBL)combined with research-based learning(RBL)in enhancing evidence-based nursing practice skills of undergraduate nursing interns.Methods A total of 114 undergraduate nursing students who interned in the operating room of a ⅢA hospital in Guangzhou from July 2021 to April 2022 were selected as study subjects.A randomized cluster sampling method based on a random number table was used to divide the students into a control group and a trial group.The control group received traditional teaching methods,while the trial group was taught using a combination of TBL and RBL.The two groups were compared in terms of evidence-based practice skills,critical thinking abilities,and their evaluations on the teaching methods.Results The differences in evidence-based practice skills and critical thinking abilities before and after the internship were significantly higher in the observation group compared to the control group(t=35.108,35.897;both P<0.05).Additionally,post-internship evaluation scores for the teaching methods in the trial group were significantly higher than those in the control group(t=-17.580,P<0.05).Conclusion TBL combined with RBL effectively enhances the evidence-based nursing practice skills and critical thinking abilities of undergraduate nursing interns.This approach also improves students'evaluations on the teaching methods and fosters the cultivation of excellent clinical evidence-based nursing professionals.