[Effects of Platelet-Rich Plasma-Derived Exosomes on Proliferation and Migration of Tendon Stem/Progenitor Cell].

Objective To investigate the effects of platelet-rich plasma-derived exosomes (PRP-Exos) on the proliferation and migration of tendon stem/progenitor cell (TSPC).Methods PRP-Exos were extracted through the combination of polymer-based precipitation and ultracentrifugation.The morphology,concentration,and particle size of PRP-Exos were identified by transmission electron microscopy and nanoparticle tracking analysis.The expression levels of surface marker proteins on PRP-Exos and platelet membrane glycoproteins were determined by Western blot analysis.Rat TSPC was extracted and cultured,and the expression of surface marker molecules on TSPC was detected using flow cytometry and immunofluorescence staining.The proliferation of TSPC influenced by PRP-Exos was evaluated using CCK-8 assay and EdU assay.The effect of PRP-Exos on the migration of TSPC was evaluated by cell scratch assay and Transwell assay.Results The extracted PRP-Exos exhibit typical saucer-like structures,with a concentration of 4.9×1011 particles/mL,an average particle size of (132.2±56.8) nm,and surface expression of CD9,CD63 and CD41.The extracted TSPC expressed the CD44 protein.PRP-Exos can be taken up by TSPC,and after co-cultured for 48 h,concentrations of 50 and 100 µg/mL of PRP-Exos significantly promoted the proliferation of TSPC (both P<0.001),with no statistical difference between the two concentrations (P=0.283).Additionally,after co-cultured for 24 h,50 µg/mL of PRP-Exos significantly promoted the migration of TSPC (P<0.001).Conclusion Under in vitro culture conditions,PRP-Exos significantly promote the proliferation and migration of rat TSPC.

[Human Platelet-Rich Plasma-Derived Exosomes Promote the Proliferation of Schwann Cells Cultured in Vitro].

Objective To investigate the effect of human platelet-rich plasma-derived exosomes(PRP-exos)on the proliferation of Schwann cell(SC)cultured in vitro. Methods PRP-exos were extracted by polymerization-precipitation combined with ultracentrifugation.The morphology of PRP-exos was observed by transmission electron microscopy,and the concentration and particle size distribution of PRP-exos were determined by nanoparticle tracking analysis.Western blotting was employed to determine the expression of the marker proteins CD63,CD81,and CD9 on exosome surface and the platelet membrane glycoprotein CD41.The SCs of rats were isolated and cultured,and the expression of the SC marker S100ß was detected by immunofluorescence staining.The fluorescently labeled PRP-exos were co-cultured with SCs in vitro for observation of their interaction.EdU assay was employed to detect the effect of PRP-exos on SC proliferation,and CCK-8 assay to detect the effects of PRP-exos at different concentrations(0,10,20,40,80,and 160 µg/ml)on SC proliferation. Results The extracted PRP-exos appeared as uniform saucer-shaped vesicles with the average particle size of(122.8±38.7)nm and the concentration of 3.5×1012 particles/ml.CD63,CD81,CD9,and CD41 were highly expressed on PRP-exos surface(P<0.001,P=0.025,P=0.004,and P=0.032).The isolated SCs expressed S100ß,and PRP-exos could be taken up by SCs.PRP-exos of 40,80,and 160 µg/ml promoted the proliferation of SCs,and that of 40 µg/ml showed the best performance(all P<0.01). Conclusions High concentrations of PRP-exos can be extracted from PRP.PRP-exos can be taken up by SCs and promote the proliferation of SCs cultured in vitro.

Differential diagnosis and feature visualization for thyroid nodules using computer-aided ultrasonic diagnosis system: initial clinical assessment.

BACKGROUND: To assess the diagnostic efficacy of the computer-aided ultrasonic diagnosis system (CAD system) in differentiating benign and malignant thyroid nodules. METHODS: The images of 296 thyroid nodules were included in validation sets. The diagnostic efficacy of the CAD system was compared with that of junior physicians and senior physicians, as well as that of the combination diagnosis of the CAD system with junior physicians. The diagnostic efficacy of the CAD system for different sizes of thyroid nodules was compared. RESULTS: The diagnostic sensitivity and accuracy of the CAD system were higher than those of junior physicians (83.4% vs. 72.2%, 73.0% vs. 69.6%), but the diagnostic specificity of the CAD system was lower than that of junior physicians (62.1% vs. 66.9%). The diagnostic accuracy of the CAD system was lower than that of senior physicians (73.0% vs. 83.8%). However, the combination diagnosis of the CAD system with junior physicians had higher accuracy (81.8%) and AUC (0.842) than those of either the CAD system or junior physicians alone, and comparable diagnostic performance with those of senior physicians. The Kappa was 0.635 in the combination diagnosis of the CAD system with junior physicians, showing good consistency with the pathological results. The accuracy (76.4%) of the CAD system was the highest for nodules of 1-2 cm. CONCLUSION: The CAD system can effectively assist physicians to identify malignant and benign thyroid nodules, reduce the overdiagnosis and overtreatment of thyroid nodules, avoid unnecessary invasive fine needle aspiration, and improve the diagnostic accuracy of junior physicians.

Targeting Diagnosis of High-Risk Papillary Thyroid Carcinoma Using Ultrasound Contrast Agent With the BRAFV600E Mutation: An Experimental Study.

OBJECTIVE: High-risk papillary thyroid carcinoma (PTC) patients with BRAF mutation have lymph node and distant metastases and poor prognosis. Therefore, this study aims to develop a targeted ultrasound contrast agent for the BRAFV600E mutation to screen high-risk PTC at early stage. METHODS: The targeted lipid nanobubbles carrying BRAFV600E antibody were prepared using thin film hydration-sonication and avidin-biotin binding methods. The physicochemical properties and stability of the targeted nanobubbles were detected by transmission electron microscopy, atomic force microscopy, and confocal laser scanning microscopy. The target binding abilities of the targeted nanobubbles in the PTC cells (B-CPAP) overexpressed mutant BRAFV600E were evaluated by immunofluorescence staining, quantitative real-time polymerase chain reaction, western blot, and fluorescence microscopy. After PTC tumor models overexpressed mutant BRAFV600E were established, the enhanced images of targeted lipid nanobubbles and untargeted lipid nanobubbles on PTC tumors in nude mice were observed using contrast-enhanced ultrasound imaging. RESULTS: The targeted lipid nanobubbles revealed uniform, round morphology, and good stability with a nanoscale size. Besides, BRAFV600E monoclonal antibody was observed to be combined on the surface of lipid nanobubbles. Furthermore, the targeted nanobubbles had a good targeting diagnosis ability in PTC cells with BRAFV600E overexpression. Moreover, the targeted nanobubbles had better ultrasound enhancement and peak intensity of the time-intensity curve (P < .001) in PTC tumors with BRAFV600E overexpression as compared to the untargeted lipid nanobubbles. CONCLUSION: The targeted lipid nanobubbles carrying BRAFV600E antibody could be regarded as a potential targeted ultrasound contrast agent for the diagnosis of high-risk PTC.

[Quantitative Evaluation of Sciatic Nerve Crush Injury with Conventional Ultrasound Combined with Shear-wave Elastography in Rabbit Models].

Objective To explore the value of conventional ultrasound combined with shear-wave elastography in the quantitative evaluation of sciatic nerve crush injury in rabbit models. Methods Forty healthy male New Zealand white rabbits were randomly divided into four groups (n=10 in each group):three crush injury (CI) groups (2,4,and 8 weeks after crush) and control group (without injury). The thickness and stiffness of the crushed sciatic nerves and denervated triceps surae muscles were measured at different time points and compared with histopathologic parameters. Inter-reader variability was assessed with intraclass correlation coefficients. Results Compared with the control group,the inner diameters of the sciatic nerves significantly increased in the 2-week CI group [(1.65±0.34) mm vs. (0.97±0.15) mm,P=0.00] but recovered to the nearly normal level in the 8-week CI group [(1.12±0.18) mm vs. (0.97±0.15) mm,P=0.06];however,compared with control group [(8.75±1.02)kPa],the elastic modulus of the nerves increased significantly in all the CI groups [2-week:(14.77±2.53) kPa;4-week:(19.12±3.46) kPa;and 8-week:(28.39±5.26) kPa;all P=0.00];pathologically,massive hyperplasia of collagen fibers were found in the nerve tissues. The thickness of denervated triceps surae muscle decreased gradually,and the elastic modulus decreased 2 weeks after injury but increased gradually in the following 6 weeks;pathologically,massive hyperplasia of collagen fibers and adipocytes infiltration were visible,along with decreased muscle wet-weight ratio and muscle fiber cross-sectional area. The inter-reader agreements were good. Conclusion Conventional ultrasound combined with shear-wave elastography is feasible for the quantitative evaluation of the morphological and mechanical properties of crushed nerves and denervated muscles.

[Effect of Tai Ji Quan Training on Strength and Function of Lower Limbs in the Aged].

OBJECTIVE: To observe the effect of Tai Ji Quan (TJQ) training on strength and function of lower limbs in the aged. METHODS: Sixty senile subjects were recruited and assigned to the TJQ group and the control group (imparting health knowledge)by random digit table. Patients in the TJQ group received 24-style TJQ training for 18 months (60 min each time, 5 times per week), while those in the control group were imparted with sarcopenia related causes, pathogeneses, prevention and control measures. The maximum isometric strength of bilateral iliopsoas, quadriceps femoris, tibialis anterior muscle, hamstrings; the time for 5 sitting-up tests and Time Up and Go Test (TUGT), one-leg standing time with closed eyes test; and the score of Berg balance scale were compared between the two groups. RESULTS: Compared with before treatment, muscle strength increased in the TJQ group with an average increased capacity (rate) as follows, bilateral iliopsoas 5.5 kg (16.9%), quadriceps femoris 5.5 kg (26.2%), and tibialis anterior muscle 8.5 kg (36.2%) (all P < 0.05). The time for TUGT and 5 sitting-up tests was shortened by 1.3 s (16.7%) and 0.9 s (14.5%) respectively in the TJQ group. The time for one-leg standing time with closed eyes test was increased by 8.4 s (left) and 9.1 s (right) respectively. The score of Berg balance scale increased by 4.3% (P < 0.05). Compared with the control group, bilateral quadriceps femoris and tibialis anterior muscle strength increased significantly (P < 0.01); the time for TUGT and 5 sitting-up tests, the time for one-leg standing time with closed eyes test, scores of Berg balance scale were all improved in the TJQ group after intervention (P < 0.05). CONCLUSION: TJQ training could improve strength of iliopsoas, quadriceps femoris, tibialis anterior muscle in the aged, elevate their balance and locomotor activities, and possibly prevent and treat sarcopenia.

The association between hearing threshold and urinary personal care and consumer product metabolites in middle-aged and elderly people from the USA.

Endocrine disruptors have been reported to be associated with hearing ability. However, the association between personal care and consumer product chemicals, known as commonly detected endocrine disruptors, and age-related hearing loss still remains unclear. This study aimed to examine the association between exposure to 7 personal care and consumer product chemicals and hearing thresholds in middle-aged and elderly people. A nationally representative cross-sectional study was performed. Eight hundred forty-five adults aged over 45 from the National Health and Nutrition Examination Survey (NHANES) were included in this study. Bayesian kernel machine regression (BKMR) and the k-medoid cluster analysis were used to evaluate the mixture effect of exposure to 7 chemicals on pure-tone average (PTA). Exposure to these chemicals was negatively associated with PTA. 2,5-Dichlorophenol had the greatest contribution to the mixture effect. The mixture effect was stronger in women, elderly people. Four pooled clusters were identified according to 7 chemicals exposures. Cluster 4 (high TCS exposure) showed a lower HFPTA (P = 0.00258) than cluster 3 (the lowest exposure cluster, as a reference). Our study provides evidence that exposure to personal care and consumer product chemicals might be inversely associated with PTA. More studies are needed to fully understand the association of exposure to these chemicals with hearing threshold.

A novel tissue engineered nerve graft constructed with autologous vein and nerve microtissue repairs a long-segment sciatic nerve defect.

Veins are easy to obtain, have low immunogenicity, and induce a relatively weak inflammatory response. Therefore, veins have the potential to be used as conduits for nerve regeneration. However, because of the presence of venous valves and the great elasticity of the venous wall, the vein is not conducive to nerve regeneration. In this study, a novel tissue engineered nerve graft was constructed by combining normal dissected nerve microtissue with an autologous vein graft for repairing 10-mm peripheral nerve defects in rats. Compared with rats given the vein graft alone, rats given the tissue engineered nerve graft had an improved sciatic static index, and a higher amplitude and shorter latency of compound muscle action potentials. Furthermore, rats implanted with the microtissue graft had a higher density and thickness of myelinated nerve fibers and reduced gastrocnemius muscle atrophy compared with rats implanted with the vein alone. However, the tissue engineered nerve graft had a lower ability to repair the defect than autogenous nerve transplantation. In summary, although the tissue engineered nerve graft constructed with autologous vein and nerve microtissue is not as effective as autologous nerve transplantation for repairing long-segment sciatic nerve defects, it may nonetheless have therapeutic potential for the clinical repair of long sciatic nerve defects. This study was approved by the Experimental Animal Ethics Committee of Chinese PLA General Hospital (approval No. 2016-x9-07) on September 7, 2016.

Tai Chi and whole-body vibrating therapy in sarcopenic men in advanced old age: a clinical randomized controlled trial.

This study was to investigate the effects of Tai Chi (TC) and whole-body vibration (WBV) exercise in sarcopenic men in advanced old age. Ninety sarcopenic men (mean age 88.6 years; age range 85-101 years) were divided into three groups: TC group, WBV group, and control (CON) group. Patients in the two treatment groups received 8 weeks of training in either TC or WBV, while the control group received reminders not to change their level of physical exercise or lifestyle. Patients in all groups also received health information related to sarcopenia. Muscle mass, muscle strength, and physical performance [balance, gait speed, timed-up-and-go test (TUGT), and five-times-sit-to-stand test (FTSST)] were analyzed and compared among the three groups. Finally, seventy-nine subjects completed the study (TC n = 24; WBV n = 28; and CON 27). Muscle strength was significantly increased in the TC and WBV groups compared to the control group (P < 0.01). Following 8 weeks of exercise, improvements were observed in all physical performance tests for the TC and WBV groups (P < 0.05). The improvement in balance was greater in the TC group than the WBV group. Time × Group effects revealed significant improvements in muscle strength in the lower extremities (P < 0.05) and physical performance (P < 0.01) in both the TC and WBV groups. Changes in muscle mass, as measured by dual-energy X-ray absorptiometry, did not significantly differ between groups. These findings indicate that TC and WBV are effective treatments for improving muscle strength and physical performance in sarcopenic men in advanced old age.