1.Horizontal sound localization in young and middle-aged patients with symmetric sensorineural hearing loss in noisy environments
Jinsheng DAI ; Lai WEI ; Jiaying LI ; Xing WANG ; Xiaolin HE ; Shuai NIE ; Juan ZHANG
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2025;60(7):785-791
Objective:This study evaluates the horizontal sound localization ability of young and middle-aged individuals with symmetric sensorineural hearing loss (SNHL) in noisy environments. It also examines the impact of hearing loss severity and signal-to-noise ratio (SNR) on localization accuracy.Methods:In this cross-sectional study, conducted from April 2023 to April 2024, 135 young and middle-aged patients (73 males and 62 females, aged 18-60 years) with SNHL who sought care at Beijing Chaoyang Hospital, were categorized into mild, moderate, and moderate-to-severe hearing loss groups (45 per group), with 45 normal-hearing controls (23 males and 22 females, aged 20-60 years). Participants completed localization tasks in quiet and noisy environments with SNR levels of 5 dB, 0 dB, -5 dB, and-10 dB. Root mean square error (RMSE) was used to measure localization accuracy. Repeated measures ANOVA assessed the effects of hearing loss and SNR on RMSE, while, Pearson correlation evaluated the relationship between binaural 4-frequency pure-tone average (4fPTA) and RMSE. Multiple linear regression analyzed the predictive role of 4fPTA and age.Results:(1) Two-way repeated measures ANOVA showed that both hearing loss severity and SNR significantly affected RMSE ( F=92.67, P<0.01; F=430.29, P<0.01), with a significant interaction between the two factors( F=92.67, P<0.01). (2) RMSE increased with hearing loss severity. At SNRs of 5 dB, 0 dB, and-5 dB, the moderate-to-severe group had significantly higher RMSE than the mild and moderate groups ( P<0.01). No significant differences were found between mild and moderate groups ( P=0.53, 0.57, 0.22). At-10 dB SNR, significant differences were observed across all groups ( P<0.01). (3) RMSE increased non-linearly as SNR decreased. Mean RMSE values under quiet conditions and at SNRs of 5 dB, 0 dB, -5 dB, and-10 dB were (7.43±5.01)°, (9.80±5.74)°, (11.60±6.22)°, (14.56±7.07)°, and (18.74±8.02)°, respectively. (4) RMSE was significantly positively correlated with binaural 4fPTA ( r=0.54-0.58, P<0.01). Multiple linear regression analysis indicated that the binaural average 4fPTA significantly predicted RMSE ( P<0.01), explaining 30.5%-34.1% of RMSE variance. Age did not significantly contribute to RMSE variation. Conclusions:The degree of hearing loss and background noise SNR significantly affect horizontal sound localization in young and middle-aged SNHL patients. RMSE increases with hearing loss severity and decreases with higher SNR. The interaction between hearing loss and SNR is significant, and RMSE correlates with binaural 4fPTA. However, the regression model based on 4fPTA and age explains only part of the RMSE variance, suggesting other contributing factors.
2.Atypical fibroxanthoma:clinicopathological features and prognostic analysis of 15 cases
Jiaying LIU ; Cui LIU ; Junhua WU ; Huizhen LI ; Xiu NIE ; Guixiang XIAO
Chinese Journal of Clinical and Experimental Pathology 2025;41(8):1044-1049
Purpose To investigate the clinicopathological features,differential diagnosis and prognosis of atypical fibroxanthoma(AFX).Methods Pathological features of 15 cases of AFX and 3 cases of pleomorphic dermal sarcoma(PDS)misdiagnosed as AFX were retrospectively analyzed by hematoxylin and eosin staining and immunohistochemical EnVision staining technology.Clinical information was collected and analyzed,and the relevant literatures were re-viewed.Results The age of the 15 patients with AFX ranged from 18 to 78 years,with an average age of 57 years.4 cases occurred in the head and neck,and 11 cases occurred in the trunk and limbs.3 patients with PDS misdiagnosed as AFX were aged from 56 to 60 years,with an average age of 58 years.The tumors were located in the trunk and limbs.Microscopically,15 cases of AFX and 3 cases of PDS misdiagnosed as AFX were composed of proliferative pleo-morphic and atypical spindle cells interspersed with a varying number of multinucleated cells.15 cases of AFX tumors were superficial and located in the dermis.In 3 cases of PDS misdiagnosed as AFX,1 case was located in subcutane-ous adipose tissue,1 case had superficial subcutaneous extension,and the third case had positive basal margin.Immu-nohistochemically,the immunophenotypes of the two groups were consistent.CD10 was expressed in all cases,CD68 was positive in most cases,SMA was expressed in a few cases,desmin was focal expressed in a very few cases,and S-100,SOX10,CD34,HMB-45,Melan A,STAT6 and CK(AE1/AE3)were not expressed in all cases.Ki67 prolifera-tion index ranged from 2%to 30%.15 patients with AFX were followed up from 12 to 108 months.One patient had tumor recurrence 1 year and 3 years after operation due to positive basal margin.Most of the other patients underwent extended resection after diagnosis and were in good condition without tumor recurrence and metastasis.3 cases of PDS misdiagnosed as AFX were followed up for 31 to 78 months.One patient had lung metastasis after 2 years,one patient recurred 4 times after operation,and the other patient died after 4 times of recurrence.Conclusion AFX is a rare dis-ease with similar pathological characteristics and immunophenotype to PDS.AFX can be diagnosed only when the tumor is small and completely confined to the dermis.When the maximum diameter of the tumor is more than 3 cm,or the presence of any form of subcutaneous extension requires a high level of vigilance for PDS.Careful differentiation and correct classification of AFX and PDS are very important for the treatment and prognosis of the disease.
3.Atypical fibroxanthoma:clinicopathological features and prognostic analysis of 15 cases
Jiaying LIU ; Cui LIU ; Junhua WU ; Huizhen LI ; Xiu NIE ; Guixiang XIAO
Chinese Journal of Clinical and Experimental Pathology 2025;41(8):1044-1049
Purpose To investigate the clinicopathological features,differential diagnosis and prognosis of atypical fibroxanthoma(AFX).Methods Pathological features of 15 cases of AFX and 3 cases of pleomorphic dermal sarcoma(PDS)misdiagnosed as AFX were retrospectively analyzed by hematoxylin and eosin staining and immunohistochemical EnVision staining technology.Clinical information was collected and analyzed,and the relevant literatures were re-viewed.Results The age of the 15 patients with AFX ranged from 18 to 78 years,with an average age of 57 years.4 cases occurred in the head and neck,and 11 cases occurred in the trunk and limbs.3 patients with PDS misdiagnosed as AFX were aged from 56 to 60 years,with an average age of 58 years.The tumors were located in the trunk and limbs.Microscopically,15 cases of AFX and 3 cases of PDS misdiagnosed as AFX were composed of proliferative pleo-morphic and atypical spindle cells interspersed with a varying number of multinucleated cells.15 cases of AFX tumors were superficial and located in the dermis.In 3 cases of PDS misdiagnosed as AFX,1 case was located in subcutane-ous adipose tissue,1 case had superficial subcutaneous extension,and the third case had positive basal margin.Immu-nohistochemically,the immunophenotypes of the two groups were consistent.CD10 was expressed in all cases,CD68 was positive in most cases,SMA was expressed in a few cases,desmin was focal expressed in a very few cases,and S-100,SOX10,CD34,HMB-45,Melan A,STAT6 and CK(AE1/AE3)were not expressed in all cases.Ki67 prolifera-tion index ranged from 2%to 30%.15 patients with AFX were followed up from 12 to 108 months.One patient had tumor recurrence 1 year and 3 years after operation due to positive basal margin.Most of the other patients underwent extended resection after diagnosis and were in good condition without tumor recurrence and metastasis.3 cases of PDS misdiagnosed as AFX were followed up for 31 to 78 months.One patient had lung metastasis after 2 years,one patient recurred 4 times after operation,and the other patient died after 4 times of recurrence.Conclusion AFX is a rare dis-ease with similar pathological characteristics and immunophenotype to PDS.AFX can be diagnosed only when the tumor is small and completely confined to the dermis.When the maximum diameter of the tumor is more than 3 cm,or the presence of any form of subcutaneous extension requires a high level of vigilance for PDS.Careful differentiation and correct classification of AFX and PDS are very important for the treatment and prognosis of the disease.
4.Horizontal sound localization in young and middle-aged patients with symmetric sensorineural hearing loss in noisy environments
Jinsheng DAI ; Lai WEI ; Jiaying LI ; Xing WANG ; Xiaolin HE ; Shuai NIE ; Juan ZHANG
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2025;60(7):785-791
Objective:This study evaluates the horizontal sound localization ability of young and middle-aged individuals with symmetric sensorineural hearing loss (SNHL) in noisy environments. It also examines the impact of hearing loss severity and signal-to-noise ratio (SNR) on localization accuracy.Methods:In this cross-sectional study, conducted from April 2023 to April 2024, 135 young and middle-aged patients (73 males and 62 females, aged 18-60 years) with SNHL who sought care at Beijing Chaoyang Hospital, were categorized into mild, moderate, and moderate-to-severe hearing loss groups (45 per group), with 45 normal-hearing controls (23 males and 22 females, aged 20-60 years). Participants completed localization tasks in quiet and noisy environments with SNR levels of 5 dB, 0 dB, -5 dB, and-10 dB. Root mean square error (RMSE) was used to measure localization accuracy. Repeated measures ANOVA assessed the effects of hearing loss and SNR on RMSE, while, Pearson correlation evaluated the relationship between binaural 4-frequency pure-tone average (4fPTA) and RMSE. Multiple linear regression analyzed the predictive role of 4fPTA and age.Results:(1) Two-way repeated measures ANOVA showed that both hearing loss severity and SNR significantly affected RMSE ( F=92.67, P<0.01; F=430.29, P<0.01), with a significant interaction between the two factors( F=92.67, P<0.01). (2) RMSE increased with hearing loss severity. At SNRs of 5 dB, 0 dB, and-5 dB, the moderate-to-severe group had significantly higher RMSE than the mild and moderate groups ( P<0.01). No significant differences were found between mild and moderate groups ( P=0.53, 0.57, 0.22). At-10 dB SNR, significant differences were observed across all groups ( P<0.01). (3) RMSE increased non-linearly as SNR decreased. Mean RMSE values under quiet conditions and at SNRs of 5 dB, 0 dB, -5 dB, and-10 dB were (7.43±5.01)°, (9.80±5.74)°, (11.60±6.22)°, (14.56±7.07)°, and (18.74±8.02)°, respectively. (4) RMSE was significantly positively correlated with binaural 4fPTA ( r=0.54-0.58, P<0.01). Multiple linear regression analysis indicated that the binaural average 4fPTA significantly predicted RMSE ( P<0.01), explaining 30.5%-34.1% of RMSE variance. Age did not significantly contribute to RMSE variation. Conclusions:The degree of hearing loss and background noise SNR significantly affect horizontal sound localization in young and middle-aged SNHL patients. RMSE increases with hearing loss severity and decreases with higher SNR. The interaction between hearing loss and SNR is significant, and RMSE correlates with binaural 4fPTA. However, the regression model based on 4fPTA and age explains only part of the RMSE variance, suggesting other contributing factors.
5.Horizontal sound localization in presence of noise in normal-hearing young adults
Jiaying LI ; Ningyu WANG ; Xing WANG ; Bingnan LI ; Shuai NIE ; Huan LI ; Juan ZHANG
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2024;59(3):204-211
Objective:This study investigates the effect of signal-to-noise ratio (SNR), frequency, and bandwidth on horizontal sound localization accuracy in normal-hearing young adults.Methods:From August 2022 to December 2022, a total of 20 normal-hearing young adults, including 7 males and 13 females, with an age range of 20 to 35 years and a mean age of 25.4 years, were selected to participate in horizontal azimuth recognition tests under both quiet and noisy conditions. Six narrowband filtered noise stimuli were used with central frequencies (CF) of 250, 2 000, and 4 000 Hz and bandwidths of 1/6 and 1 octave. Continuous broadband white noise was used as the background masker, and the signal-to-noise ratio (SNR) was 0, -3, and -12 dB. The root-mean-square error (RMS error) was used to measure sound localization accuracy, with smaller values indicating higher accuracy. Friedman test was used to compare the effects of SNR and CF on sound localization accuracy, and Wilcoxon signed-rank test was used to compare the impact of the two bandwidths on sound localization accuracy in noise.Results:In a quiet environment, the RMS error in horizontal azimuth in normal-hearing young adults ranged from 4.3 to 8.1 degrees. Sound localization accuracy decreased with decreasing SNR: at 0 dB SNR (range: 5.3-12.9 degrees), the difference from the quiet condition was not significant ( P>0.05); however, at -3 dB (range: 7.3-16.8 degrees) and -12 dB SNR (range: 9.4-41.2 degrees), sound localization accuracy significantly decreased compared to the quiet condition (all P<0.01). Under noisy conditions, there were differences in sound localization accuracy among stimuli with different frequencies and bandwidths, with higher frequencies performing the worst, followed by middle frequencies, and lower frequencies performing the best, with significant differences (all P<0.01). Sound localization accuracy for 1/6 octave stimuli was more susceptible to noise interference than 1 octave stimuli (all P<0.01). Conclusions:The ability of normal-hearing young adults to localize sound in the horizontal plane in the presence of noise is influenced by SNR, CF, and bandwidth. Noise with SNRs of ≥-3 dB can lead to decreased accuracy in narrowband sound localization. Higher CF signals and narrower bandwidths are more susceptible to noise interference.
6.Comparison of horizontal plane auditory spatial discrimination abilities and testing methods in patients with symmetrical sensorineural hearing loss
Lai WEI ; Jiaying LI ; Xing WANG ; Xiaolin HE ; Shuai NIE ; Xin FU ; Huan LI ; Jiaxing LIU ; Xuelei ZHAO ; Zihui ZHAO ; Ningyu WANG ; Juan ZHANG
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2024;59(9):922-927
Objective:To evaluate auditory spatial discrimination capabilities in patients with mild to moderately severe symmetrical sensorineural hearing loss (SNHL) and to compare the impact of different psychophysical testing methods on Minimum Audible Angle (MAA) and test duration.Methods:A total of 105 symmetrical SNHL patients aged from 18 to 60 years old were enrolled from April to July 2023, including 56 males and 49 females. They were divided into three groups based on PTA: mild, moderate, and moderately severe hearing loss, with 35 individuals in each group. Additionally, a control group of 35 individuals with normal hearing was tested, including 18 males and 17 females. Participants underwent four distinct psychophysical discrimination tests: the block up-down, 1-up/1-down, 1-up/2-down, and 1-up/3-down procedures. We recorded the MAA and test duration for each. We employed repeated measures of ANOVA to compare the MAA and test duration across different methods and groups, and Pearson′s correlation to assess the relationship between MAA and degree of hearing loss.Results:MAA of sound localization in patients with symmetrical SNHL was significantly positively correlated with the degree of hearing loss ( r=0.59, P<0.01). Significant deterioration in MAA was observed as hearing loss progressed to the moderate level (PTA≥35 dBHL, P<0.01). The testing methods significantly influenced MAA and testing duration ( F=24.02, P<0.01; F=75.56, P<0.01) and the 1-up/1-down method was the quickest, averaging only (0.69±0.32) mins. Conclusions:The horizontal plane auditory spatial discrimination abilities in patients with symmetrical SNHL is impaired progressively with increasing hearing loss, notably beyond moderate hearing loss levels. Different psychophysical methods influence both MAA and test duration, the quicker 1-up/1-down method is recommended for assessing MAA in symmetrical SNHL patients.
7. Construction of tissue engineered adipose by human adipose tissue derived extracellular vesicle combined with decellularized adipose tissues scaffold
Chinese Journal of Reparative and Reconstructive Surgery 2020;34(2):226-233
Objective: To explore the possibility of constructing tissue engineered adipose by adipose tissue derived extracellular vesicles (hAT-EV) combined with decellularized adipose tissue (DAT) scaffolds, and to provide a new therapy for soft tissue defects. Methods: The adipose tissue voluntarily donated by the liposuction patient was divided into two parts, one of them was decellularized and observed by HE and Masson staining and scanning electron microscope (SEM). Immunohistochemical staining and Western blot detection for collagen type Ⅰ and Ⅳ and laminin were also employed. Another one was incubated with exosome-removed complete medium for 48 hours, then centrifuged to collect the medium and to obtain hAT-EV via ultracentrifugation. The morphology of hAT-EV was observed by transmission electron microscopy; the nanoparticle tracking analyzer (NanoSight) was used to analyze the size distribution; Western blot was used to analyse membrane surface protein of hAT-EV. Adipose derived stem cells (ADSCs) were co-cultured with PKH26 fluorescently labeled hAT-EV, confocal fluorescence microscopy was used to observe the uptake of hAT-EV by ADSCs. Oil red O staining was used to evaluate adipogenic differentiation after hAT-EV and ADSCs co-cultured for 15 days. The DAT was scissored and then injected into the bilateral backs of 8 C57 mice (6-week-old). In experimental group, 0.2 mL hAT-EV was injected weekly, and 0.2 mL PBS was injected weekly in control group. After 12 weeks, the mice were sacrificed, and the new fat organisms on both sides were weighed. The amount of new fat was evaluated by HE and peri-lipoprotein immunofluorescence staining to evaluate the ability of hAT-EV to induce adipogenesis in vivo. Results: After acellularization of adipose tissue, HE and Masson staining showed that DAT was mainly composed of loosely arranged collagen with no nucleus; SEM showed that no cells and cell fragments were found in DAT, and thick fibrous collagen bundles could be seen; immunohistochemical staining and Western blot detection showed that collagen type Ⅰ and Ⅳ and laminin were retained in DAT. It was found that hAT-EV exhibited a spherical shape of double-layer envelope, with high expressions of CD63, apoptosis-inducible factor 6 interacting protein antibody, tumor susceptibility gene 101, and the particle size of 97.9% hAT-EV ranged from 32.67 nmto 220.20 nm with a peak at 91.28 nm. Confocal fluorescence microscopy and oil red O staining showed that hAT-EV was absorbed by ADSCs and induced adipogenic differentiation. In vivo experiments showed that the wet weight of fat new organisms in the experimental group was significantly higher than that in the control group ( t=2.278, P=0.048). HE staining showed that the structure of lipid droplets in the experimental group was more than that in the control group, and the collagen content in the control group was higher than that in the experimental group. The proportion of new fat in the experimental group was significantly higher than that in the control group ( t=4.648, P=0.017). Conclusion: DAT carrying hAT-EV can be used as a new method to induce adipose tissue regeneration and has a potential application prospect in the repair of soft tissue defects.
8. Acellular adipose tissue preparation: A soft-tissue filler allowing for allogeneic injection or in situ adipogenesis?
Chinese Journal of Tissue Engineering Research 2020;24(11):1762-1768
BACKGROUND: Construction of seedless tissue-engineered adipose tissue from acellular adipose tissue is a hot research topic in soft tissue filling. OBJECTIVE: To investigate the effects of preparation methods of acellular adipose tissue on the induction of adipose regeneration after transplantation in recent years, and to look forward to its clinical application prospects. METHODS: A computer-based online search of PubMed and Elsevier databases was performed to retrieve papers regarding acellular adipose tissue preparation and transplantation published between January 1971 and December 2018 with the search terms “adipose tissue engineering; adipose tissue extracellular matrix; soft tissue repair; angiogenesis; adipogenic induction”. The retrieved papers were summarized from the perspectives of improvement in preparation methods of acellular adipose tissue, cross-linking cytokines and biomaterials. RESULTS AND CONCLUSION: Retrieved studies have shown that extracellular matrix of adipose tissue can act as an ideal scaffold material for soft tissue filling. Subcutaneous implantation of extracellular matrix of adipose tissue can recruit host stem cells and induce their proliferation and adipogenesis. However, existing acellular schemes can lead to the loss of extracellular matrix proteins and structures. This greatly affects the fat regeneration ability of acellular adipose tissue implanted in vivo. However, supercritical carbon dioxide deoiling, mechanical pretreatment, cross-linking cytokines or biomaterials can reduce the loss of extracellular matrix proteins and supplement the proteins that promote tissue regeneration during the preparation of acellular adipose tissue. This can ultimately enhance the angiogenesis and adipogenesis of acellular adipose tissue after transplantation. Acellular adipose tissue has strong application prospects in adipose tissue engineering because of its natural adipogenic induction ability. If the loss of extracellular matrix protein can be overcome during preparation of acellular adipose tissue or under the premise of safety and controllability, acellular adipose tissue is expected to become a suitable soft tissue filler that allows allogeneic injection and in situ adipogenesis.
9.Study on molecular mechanism of extracellular vesicles derived from adipose-derived stem cells regulating TGF-β-Smad signaling pathway to inhibit scar hyperplasia
Yuanzheng ZHU ; Yangyan YI ; Jiangwen WANG ; Jiaying NIE ; Zhaohui WANG ; Shu WU ; Juanmin YANG
Chinese Journal of Plastic Surgery 2020;36(10):1114-1120
Objective:This study aims to explore the potential effects of adipose-derived stem cell-extracellular vesicles(ASC-EVs) on TGFβ-Smad signaling pathway during myofibroblast trans-differentiation in vitro. Methods:ASCs were isolated from liposuction and flow cytometry was used to detect the surface protein markers. ASC-EVs were isolated from the supernatant of the third to fifth generation ASCs, and the microscopic morphology was observed by transmission electron microscope. The particle size distribution was detected by nano-particle tracking analyzer NanoSight and the membrane surface marker proteins CD63, Alix and TSG101 were detected by flow cytometry. The uptake of EVs by dermal fibroblasts co-cultured with PKH67 fluorescence labeled ASC-EVs was observed by confocal microscope. Dermal fibroblasts were continuously induced by TGFβ1 for five days, and ASC-EVs at the dose of 50 and 100 μg/ml were added. The expression of α-SMA and Smad-2/3/4 were detected by immunofluorescence staining, RT-PCR and Western Blot.Results:The results of flow cytometry showed that the surface markers CD73, CD49d, CD90 and CD105 of the third generation ASCs, were positive, and CD34 and CD45 were negative. Under transmission electron microscope, ASC-EVs was a round membranous vesicle with clear edge and surrounded by bilayer phospholipid membrane. The particle size of more than 95% of the ASC-EVs was distributed between 30 nm to 261 nm, with an average of (166.0±86.1)nm. The specific marker proteins of extracellular vesicle, CD63, Alix and TSG101 were highly expressed. Under confocal microscope, ASC-EVs with green fluorescence were uptake by dermal fibroblasts and distributed in the cytoplasm, and part of ASC-EVs was distributed around the nucleus.TGF-β1 induced a significant increase in the expression of α-SMA in dermal fibroblasts, and the addition of 50 or 100 μg/ml ASC-EVs reduced the expression of α-SMA genes and proteins, but did not show a dose-dependent manner. The gene and protein expression changes of Smad-2/3/4 were consistent with α-SMA. In addition, ASC-EVs could significantly reduced the content of type Ⅰ collagen in the supernatant, but had no significant effect on the secretion of type Ⅲ collagen.Conclusions:The mechanism of ASC-EVs inhibiting scar hyperplasia may be closely related to the suppression of TGF-β-Smad signaling pathway in dermal fibroblasts, inhibition of myofibroblast trans-differentiation and reduction of type Ⅰ collagen secretion.
10.Study on molecular mechanism of extracellular vesicles derived from adipose-derived stem cells regulating TGF-β-Smad signaling pathway to inhibit scar hyperplasia
Yuanzheng ZHU ; Yangyan YI ; Jiangwen WANG ; Jiaying NIE ; Zhaohui WANG ; Shu WU ; Juanmin YANG
Chinese Journal of Plastic Surgery 2020;36(10):1114-1120
Objective:This study aims to explore the potential effects of adipose-derived stem cell-extracellular vesicles(ASC-EVs) on TGFβ-Smad signaling pathway during myofibroblast trans-differentiation in vitro. Methods:ASCs were isolated from liposuction and flow cytometry was used to detect the surface protein markers. ASC-EVs were isolated from the supernatant of the third to fifth generation ASCs, and the microscopic morphology was observed by transmission electron microscope. The particle size distribution was detected by nano-particle tracking analyzer NanoSight and the membrane surface marker proteins CD63, Alix and TSG101 were detected by flow cytometry. The uptake of EVs by dermal fibroblasts co-cultured with PKH67 fluorescence labeled ASC-EVs was observed by confocal microscope. Dermal fibroblasts were continuously induced by TGFβ1 for five days, and ASC-EVs at the dose of 50 and 100 μg/ml were added. The expression of α-SMA and Smad-2/3/4 were detected by immunofluorescence staining, RT-PCR and Western Blot.Results:The results of flow cytometry showed that the surface markers CD73, CD49d, CD90 and CD105 of the third generation ASCs, were positive, and CD34 and CD45 were negative. Under transmission electron microscope, ASC-EVs was a round membranous vesicle with clear edge and surrounded by bilayer phospholipid membrane. The particle size of more than 95% of the ASC-EVs was distributed between 30 nm to 261 nm, with an average of (166.0±86.1)nm. The specific marker proteins of extracellular vesicle, CD63, Alix and TSG101 were highly expressed. Under confocal microscope, ASC-EVs with green fluorescence were uptake by dermal fibroblasts and distributed in the cytoplasm, and part of ASC-EVs was distributed around the nucleus.TGF-β1 induced a significant increase in the expression of α-SMA in dermal fibroblasts, and the addition of 50 or 100 μg/ml ASC-EVs reduced the expression of α-SMA genes and proteins, but did not show a dose-dependent manner. The gene and protein expression changes of Smad-2/3/4 were consistent with α-SMA. In addition, ASC-EVs could significantly reduced the content of type Ⅰ collagen in the supernatant, but had no significant effect on the secretion of type Ⅲ collagen.Conclusions:The mechanism of ASC-EVs inhibiting scar hyperplasia may be closely related to the suppression of TGF-β-Smad signaling pathway in dermal fibroblasts, inhibition of myofibroblast trans-differentiation and reduction of type Ⅰ collagen secretion.

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