Objective:To investigate the role of umbilical cord mesenchymal stem cell (MSC) -derived nanovesicles in hair regeneration.Methods:(1) Nanovesicles were prepared by continuously extruding umbilical cord MSCs through polycarbonate membranes, and were identified using transmission electron microscopy and nanoparticle tracking analysis. (2) Six C57BL/6 female mice with full-thickness skin wounds were randomly divided into a nanovesicle group (subcutaneously injected with nanovesicles once at the wound margin) and a control group (subcutaneously injected with an equal volume of phosphate-buffered saline [PBS] at the wound margin) ; skin samples were collected on day 16 for hematoxylin-eosin (HE) staining to assess wound healing and hair follicle regeneration. (3) Human hair follicle dermal papilla cells (DPCs) were isolated using a two-step enzyme method; the uptake of PKH26-pre-labeled nanovesicles by DPCs was observed by fluorescence microscopy; the proliferative activity of DPCs co-cultured with nanovesicles was evaluated using cell counting kit-8 (CCK8) and 5-ethynyl-2'-deoxyuridine (EdU) assays. (4) Six healthy C57BL/6 female mice were randomly divided into two groups after anesthesia, and subcutaneously injected with either fluorescent dye DIR-pre-labeled nanovesicles or PBS; an in vivo imaging system was used to observe the uptake and metabolism of nanovesicles in the mouse skin. (5) Twenty-four C57BL/6 female mice with depilated backs were randomly divided into a nanovesicle group (subcutaneously injected with nanovesicles on days 0, 8, and 15) and a control group (subcutaneously injected with an equal volume of PBS at the same time points) ; skin samples were collected on days 4, 18, and 21 for HE staining to analyze differences in hair follicle cycling; transcriptome sequencing was performed on skin samples collected on day 4. Statistical analyses were conducted using the t test. Results:(1) Transmission electron microscopy showed that nanovesicles exhibited a spherical membranous structure with diameters of 141.3 ± 60.0 nm. (2) In 6 C57BL/6 female mice with full-thickness skin wounds, the wound area on day 12 was significantly smaller in the nanovesicle group (1.27 ± 0.50 mm 2) than in the control group (4.13 ± 1.03 mm 2, t = 4.34, P = 0.012). (3) Fluorescence microscopy revealed that nanovesicles were taken up by DPCs within 20 hours; the absorbance of DPCs was significantly higher in the nanovesicle group than in the control group ( t = 20.23, P < 0.001), and the percentage of EdU-positive cells was also significantly higher in the nanovesicle group (49.62% ± 6.45%) than in the control group (37.58% ± 3.42%, t = 3.69, P = 0.006). (4) In vivo imaging of the 6 C57BL/6 female mice showed strong fluorescence in the back of mice in the nanovesicle group on day 0, which markedly decreased by day 8, while no fluorescence was observed in the control group throughout the experiment. (5) Hair follicle cycle experiments on the 24 C57BL/6 female mice with depilated backs showed that the hair follicle length on day 4 after depilation was significantly longer in the nanovesicle group (368.00 ± 63.17 μm) than in the control group (266.90 ± 34.41 μm, t = 9.87, P < 0.001), and the hair bulb diameter was also significantly longer in the nanovesicle group (54.83 ± 10.32 μm) than in the control group (39.12 ± 7.54 μm, t = 16.02, P < 0.001) ; on day 18, the nanovesicle group showed a significantly higher hair follicle density (19.12 ± 0.90) compared with the control group (11.07 ± 1.51, t = 7.92, P = 0.001) ; on day 21, 46.13% ± 8.64% of hair follicles in the nanovesicle group remained in the anagen phase Ⅵ to the catagen phase Ⅱ, and 46.24% ± 3.29% were in the catagen phases Ⅲ to Ⅳ, while 78.89% ± 18.36% of hair follicles in the control group were in the telogen phases Ⅶ to Ⅷ. Transcriptome sequencing showed that differentially expressed genes in the nanovesicle group were significantly positively enriched in the keratinization process (NES = 2.23, P < 0.001) . Conclusion:Umbilical cord MSC-derived nanovesicles could promote the proliferation of DPCs, advance the entry of hair follicles into the anagen phase, delay their entry into the catagen phase, and induce hair regeneration.

Objective:To investigate the role of umbilical cord mesenchymal stem cell (MSC) -derived nanovesicles in hair regeneration.Methods:(1) Nanovesicles were prepared by continuously extruding umbilical cord MSCs through polycarbonate membranes, and were identified using transmission electron microscopy and nanoparticle tracking analysis. (2) Six C57BL/6 female mice with full-thickness skin wounds were randomly divided into a nanovesicle group (subcutaneously injected with nanovesicles once at the wound margin) and a control group (subcutaneously injected with an equal volume of phosphate-buffered saline [PBS] at the wound margin) ; skin samples were collected on day 16 for hematoxylin-eosin (HE) staining to assess wound healing and hair follicle regeneration. (3) Human hair follicle dermal papilla cells (DPCs) were isolated using a two-step enzyme method; the uptake of PKH26-pre-labeled nanovesicles by DPCs was observed by fluorescence microscopy; the proliferative activity of DPCs co-cultured with nanovesicles was evaluated using cell counting kit-8 (CCK8) and 5-ethynyl-2'-deoxyuridine (EdU) assays. (4) Six healthy C57BL/6 female mice were randomly divided into two groups after anesthesia, and subcutaneously injected with either fluorescent dye DIR-pre-labeled nanovesicles or PBS; an in vivo imaging system was used to observe the uptake and metabolism of nanovesicles in the mouse skin. (5) Twenty-four C57BL/6 female mice with depilated backs were randomly divided into a nanovesicle group (subcutaneously injected with nanovesicles on days 0, 8, and 15) and a control group (subcutaneously injected with an equal volume of PBS at the same time points) ; skin samples were collected on days 4, 18, and 21 for HE staining to analyze differences in hair follicle cycling; transcriptome sequencing was performed on skin samples collected on day 4. Statistical analyses were conducted using the t test. Results:(1) Transmission electron microscopy showed that nanovesicles exhibited a spherical membranous structure with diameters of 141.3 ± 60.0 nm. (2) In 6 C57BL/6 female mice with full-thickness skin wounds, the wound area on day 12 was significantly smaller in the nanovesicle group (1.27 ± 0.50 mm 2) than in the control group (4.13 ± 1.03 mm 2, t = 4.34, P = 0.012). (3) Fluorescence microscopy revealed that nanovesicles were taken up by DPCs within 20 hours; the absorbance of DPCs was significantly higher in the nanovesicle group than in the control group ( t = 20.23, P < 0.001), and the percentage of EdU-positive cells was also significantly higher in the nanovesicle group (49.62% ± 6.45%) than in the control group (37.58% ± 3.42%, t = 3.69, P = 0.006). (4) In vivo imaging of the 6 C57BL/6 female mice showed strong fluorescence in the back of mice in the nanovesicle group on day 0, which markedly decreased by day 8, while no fluorescence was observed in the control group throughout the experiment. (5) Hair follicle cycle experiments on the 24 C57BL/6 female mice with depilated backs showed that the hair follicle length on day 4 after depilation was significantly longer in the nanovesicle group (368.00 ± 63.17 μm) than in the control group (266.90 ± 34.41 μm, t = 9.87, P < 0.001), and the hair bulb diameter was also significantly longer in the nanovesicle group (54.83 ± 10.32 μm) than in the control group (39.12 ± 7.54 μm, t = 16.02, P < 0.001) ; on day 18, the nanovesicle group showed a significantly higher hair follicle density (19.12 ± 0.90) compared with the control group (11.07 ± 1.51, t = 7.92, P = 0.001) ; on day 21, 46.13% ± 8.64% of hair follicles in the nanovesicle group remained in the anagen phase Ⅵ to the catagen phase Ⅱ, and 46.24% ± 3.29% were in the catagen phases Ⅲ to Ⅳ, while 78.89% ± 18.36% of hair follicles in the control group were in the telogen phases Ⅶ to Ⅷ. Transcriptome sequencing showed that differentially expressed genes in the nanovesicle group were significantly positively enriched in the keratinization process (NES = 2.23, P < 0.001) . Conclusion:Umbilical cord MSC-derived nanovesicles could promote the proliferation of DPCs, advance the entry of hair follicles into the anagen phase, delay their entry into the catagen phase, and induce hair regeneration.

Mice ; Animals ; Myocytes, Cardiac ; MicroRNAs/genetics* ; RNA, Long Noncoding/genetics* ; Cardiomegaly/genetics* ; Signal Transduction ; Cells, Cultured

To scientifically evaluate the intervention effect of Chinese medicine preventive administration(combined use of Huo-xiang Zhengqi Oral Liquid and Jinhao Jiere Granules) on community population in the case of coronavirus disease 2019(COVID-19), a large cohort, prospective, randomized, and parallel-controlled clinical study was conducted. Total 22 065 subjects were included and randomly divided into 2 groups. The non-intervention group was given health guidance only, while the traditional Chinese medicine(TCM) intervention group was given two coordinated TCM in addition to health guidance. The medical instructions were as follows. Huoxiang Zhengqi Oral Liquid: oral before meals, 10 mL/time, 2 times/day, a course of 5 days. Jinhao Jiere Granules: dissolve in boiling water and take after meals, 8 g/time, 2 times/day, a course of 5 days, followed up for 14 days, respectively. The study found that with the intake of medication, the incidence rate of TCM intervention group was basically maintained at a low and continuous stable level(0.01%-0.02%), while the non-intervention group showed an overall trend of continuous growth(0.02%-0.18%) from 3 to 14 days. No suspected or confirmed COVID-19 case occurred in either group. There were 2 cases of colds in the TCM intervention group and 26 cases in the non-intervention group. The incidence of colds in the TCM intervention group was significantly lower(P<0.05) than that in the non-intervention group. In the population of 16-60 years old, the incidence rate of non-intervention and intervention groups were 0.01% and 0.25%, respectively. The difference of colds incidence between the two groups was statistically significant(P<0.05). In the population older than 60 years old, they were 0.04% and 0.21%, respectively. The incidence of colds in the non-intervention group was higher than that in the intervention group, but not reaching statistical difference. The protection rate of TCM for the whole population was 91.8%, especially for the population of age 16-60(95.0%). It was suggested that TCM intervention(combined use of Huoxiang Zhengqi Oral Liquid and Jinhao Jiere Granules) could effectively protect community residents against respiratory diseases, such as colds, which was worthy of promotion in the community. In addition, in terms of safety, the incidence of adverse events and adverse reactions in the TCM intervention group was relatively low, which was basically consistent with the drug instructions.
Adolescent ; Adult ; Betacoronavirus ; Coronavirus Infections ; drug therapy ; Drugs, Chinese Herbal ; Humans ; Medicine, Chinese Traditional ; Middle Aged ; Pandemics ; Pneumonia, Viral ; drug therapy ; Prospective Studies ; Young Adult

OBJECTIVE: The aim of this study was to explore the theoretical framework of cells and the forms of osteogenesis in the mechanism by which demineralized dentin matrix (DDM) induces osteogenesis. METHODS: A total of 24 New Zealand rabbits were used in this study. A total of 4 erector spinae bags were created in each animal. A total of 3 erector spinae bags were implanted with DDM by random selection, whereas the remaining one erector spinae bag was not implanted with DDM. The rabbits were sacrificed after 1, 2, 3, 4, 8, 12, 16, and 20 weeks, and the samples were obtained. The samples were examined by hematoxylin-eosin (HE), tartrate-resistant acid phosphatase (TRAP), and immunohistochemical staining to identify the mesenchymal stem cells, osteoblasts, chondrocytes, and osteoclasts. RESULTS: The results of HE staining showed that in the third week, cartilage- and bone-like matrices, as well as the osteoblast-like cells, were observed. The results of immunohistochemical staining showed that the expressions of CD44, alkaline phosphatase (ALP), and collagen Ⅱ were statistically significant 
(P<0.05). CONCLUSIONS DDM has good histocompatibility and osteoinduction. In addition, induced ectopic osteogenesis mode mainly occurs in the endochondral bone.
Animals ; Bone Matrix ; Dentin ; Osteoblasts ; Osteogenesis ; Rabbits ; Tooth Demineralization

Objective To sum up the clinical information and outcomes of one-stage surgical repairs for interrupted aortic arch (IAA) associated with cardiac defects through median stemotomy in infant.Methods From August 2005 to January 2012,23 IAA patients,aged 18 days to 3 years [mean age (8.61 ± 11.81) months],body weight 3.3-13.0 kg [mean (6.61 ± 3.26) kg] were reviewed underwent one-stage repair.There were 12 male and 11 female.The anatomic subtype ineluded type A 20 (87.0％),type B 3 (13.0％),and no type C in the records.All cases included ventricular septal defect and patent ductus artefious,some also with artirical-pulmonary window,aterical septal defect,bicuspid or unicuspid aortic valve,and subvalvular aortic stenosis.Diagnosis was determined in of the patients and suspected in by echocardiography.Also,64 layers helico-CT was employed to make a definite diagnosis for 18 patients and cardiac catheterization was used for 4 patients.All patients with cardiac anomalies underwent one-stage repair through median sternotomy.The aortic continuity was reestablished by anastomosis between the descending aortic segment and aortic arch.Results In all 23 cases,21 were successful.There was 2 (8.69％) postoperative death:one was due to surgical hemorrhage and severe low cardiac output during perioperative stage and the other was 2-month old due to crisis of pulmonary hypertension.CPB time was ranged from 53-215 min [(129.76 ± 38.98) min],and aortic crossclamp time was 34-125 min[(74.47 ± 24.30) min].The length of stay in ICU postoperatively was 96h averagely.The postoperative complications included severe low cardiac output syndrome in 3 patients,hypoxemia in 13,pneumonia in 7,and supraventricular tachycardia in 12.21 patients were followed up from 2 months to 6 years and were in good condition without recoactation.Conclusion The outcomes of early and medium term for one-stage repair of IAA and associated cardiac anomalies through median stemotomy is excellent.Technique of extended anastomosis between the descending aortic segment and aortic arch may reduce the incidence of recoarctation.It is simplified the procedure and improved life quality of patients.

Objective To investigate the influence of membrane molecular weight cut off in our bioartificial liver(BAL)system.Methods Beagle dogs were used for a model of acute liver failure through D-galactosamine administration.The acute liver failure Beagles were divided into two groups by the membrane molecular weight cut off.Group A was treated with BAL containing 200 kDa retention rating membrane.Group B was treated with BAL containing 1200 kDa retention rating membrane.Each group underwent two six-hour BAL treatments that were performed on day 1 and day 21.BAL medium were examined and levels of IgG,IgM,and complement hemolytic unit of 50％(CH50)antibodies were measured in all Beagles and.Results BAL treatment was associated with a significant decline in levels of CH50.1200 kDa group experienced a significant increase in levels of IgG and IgM after two BAL treatments.Significant levels of canine proteins were detected in BAL medium from 1200 kDa group.Conclusions Xenogeneic immune response in the BAL system was influenced by membrane molecular weight cut off.

Objective As an effective means of liver function support for acute liver failure, bioartificial liver has seen great progress in recent years. However, the development of this type of device is currently hindered by limited oxygen transport to cultured hepatocytes. In this study we try to resolve this problem by supplementing the circulating medium of the bioreactor with red blood cells.Methods Freshly isolated primary porcine hepatocytes were inoculated into our newly designed bioreactor and were divided into two groups: RPMI1640 was circulated in the control group and porcine red blood cells were added into the culture medium in the experimental group. The culture media in both groups were oxygenated through extra-corporeal membrane oxygenation, and the oxygen consumption rate (OCR) in the bioreactor was measured by a blood gas analyzer. Liver-specific functions and glucose consumption were also determined. Results The OCR of the experimental group was 1.5 fold that of the control group, and the glucose consumption rate was twice that of the control group. The liver-specific functions of the experimental group were significantly higher than those of the control group in terrns of albumin secretion and urea synthesis. Conclusion Supplementing the circulating medium of the bioreactor with red blood cells can significantly improve the oxygen supply in the bioreactor, thereby enhancing the glucose consumption and liver-specific functions of hepatocytes. This method is convenient and effective, and is expected to be an effective means to resolve the problems of oxygen supply in the bioreactor.

Objective To investigate the role of IL-6 in the co-cultivation system of porcine hepatocytes with bone marrow mesenchymal stem cells (MSCs) in vitro.Methods Mononuclear cells were isolated from bone marrow aspirate of swines (n = 3) by 1.077 g/ml density gradient centrifugation.MSCs of passage 3 and primary hepatocytes harvested by a two-step in situ collagenase perfusion technique were inoculated in Millicell culture inserts at a seeding ratio of 1:2,and functional changes of heterotypic interactions were characterized.Levels of IL-6,TNF-α,and TGF-α were measured respectively.Results Hepatocyte viability was greater than 95%.Hepatocyte performance levels such as albumin secretion and urea synthesis were all significantly enhanced in co-culture group compared with hepatocyte homo-culture (P＜0.05).The IL-6 level also significantly increased in co-culture group (P ＜ 0.01).A significant decrease of hepatic functions was observed upon neutralization of IL-6 in co-culture.Conclusion MSC-derived IL-6 plays a key role in the up-regulation of hepatocyte functions in this co-culture.