BACKGROUND:Previous experiments have shown that improved platelet-rich plasma can promote the proliferation of human dental pulp cells in a concentration-dependent manner, particularly when the concentration is 10%.
OBJECTIVE:To investigate the effect of platelet-rich plasma at different concentrations on the proliferation and immunogenicity of human bone marrow mesenchymal stem cells.
METHODS:Human bone marrow mesenchymal stem cells from healthy donors were cultured and passaged for 3-4 passages, identified by flow cytometry and differentiation inductions. Platelet-rich plasma samples which were manufactured from the venous blood of the same donor were used for culturing human bone marrow mesenchymal stem cells. The proliferation of human bone marrow mesenchymal stem cells was measured by cellcounting kit-8 method and the growth curves were drawn. The most suitable concentration of platelet-rich plasma was selected to culture human bone marrow mesenchymal stem cells for three generations and the Stro-1 expression rate on the surface of human bone marrow mesenchymal stem cells was determined through flow cytometry.
RESULTS AND CONCLUSION:Platelet-rich plasma at the concentration of 5%-10%evidently promoted the proliferation of human bone marrow mesenchymal stem cells on the 6th and 8th days. The most effective concentration to promote the proliferation was 10%. Platelet-rich plasma at the concentration of 10%stil promoted the proliferation of human bone marrow mesenchymal stem cells on the 10th day, and maintained a better immunogenicity of human bone marrow mesenchymal stem cells compared to the control group. These findings indicate that platelet-rich plasma can promote the proliferation of human bone marrow mesenchymal stem cells in a concentration-dependent manner, and 10%platelet-rich plasma is better to maintain the immunogenicity of human bone marrow mesenchymal stem cells.

BACKGROUND: Many clinical cases have proved that the satisfactory reposition, fusion and internal fixation in the internal fixation for inferior lumbar spondylolisthesis are not consistent with the postoperative symptoms and physical signs, and functional restoration.OBJECTIVE: To investigate the application of somatosensory evoked potential(SEP) in the monitoring during internal fixation for inferior lumbar spondylolisthesis, and the effects of SEP monitoring on the improvement of postoperative symptoms and the spinal functions as well.DESIGN: A randomized controlled trial.SETTING: Inpatient department of spinal surgery, an affiliated hospital of a university. PARTICIPANTS: Fifty-two patients with inferior lumbar spomlylolisthesis including 23 male and 29 female cases aged between 18 and 68 years old were admitted by the Department of Spinal Surgery, Second Affiliated Hospital(Shenzhen People's Hospital) of Jinan University, from June 2000 to December 2003. All cases were randomly divided into control group(n = 20) and monitor group ( n = 32).METHODS: SEP induced by segmental stimulation in cutaneous nerve was used in the control group for preoperative and intraoperative monitoring, and postoperative follow up. The intraoperative potential changes in patients with excellent and good improvement in postoperative functions had been retrospectively investigated to confirm the effective indices for intraoperative monitoring, which thereby provided references for intraoperative monitoring in patients of monitor group.MAIN OUTCOME MEASURES: ① Evaluation of postoperative spinal function; ② SEP latency and amplitude.RESULTS: SEP values after postoperative anesthesia were set as basis.The manifestations of intraoperative potential alterations: ① If the latency reduced 10% -15% or the amplitude increases more than 40% after fixation, it suggested favorable prognosis; ② The potential indices were stable during monitoring, or the reduction of latency was less than 10%,or the increase of amplitude was less than 30%, the fixation could be continued, and partial functions of nerve root and symptoms could be improved after surgery; ③ During the surgery, if potential indices had transient lluctuation, which could be recovered to basic potential within 15 to 20 minutes, fixation should be stopped during the fluctuation. Still partial functions of nerve root and symptoms could be improved after surgery; ④If the intraoperative latency prolonged more than 5%, or amplitude reduced more than 10%, or part of the components disappeared, or the wave shape dispersed, it might suggest postoperative aggravation of pain and dyskinesia. So intraoperative adjustment was necessary. The coincident rate of the improvement of the indices of intraoperative monitoring and the improvement of postoperative spinal function reached 93.75%.CONCLUSION: SEP induced by segrmental stimulation in cutaneous nerve is an objective and effective method in the monitoring and instruction of decompression, reposition, fixation of internal fixation for inferior lumbar spondylolisthesis, which has important merits in the improvement of the function of nerve root and the restoration of spinal function.

BACKGROUND:Previous experiments have shown that modified platelet-rich plasma activated by liquid nitrogen freezing and thawing can promote the proliferation of human bone marrow mesenchymal stem cells and dental pulp stem cells in a concentration-dependent manner. OBJECTIVE:To investigate the effect of modified platelet-rich plasma at different concentrations on the proliferation of dental pulp stem cells from human exfoliated deciduous teeth. METHODS:Platelets were selected and harvested by automatic blood cellanalyzer, and then activated by liquid nitrogen freezing and thawing.α-MEM served as basal medium. Different concentrations of modified platelet-rich plasma (2%, 5%, 10%, 20%) or 10%fetal bovine serum were added, respectively. The difference in cellproliferation was observed. RESULTS AND CONCLUSION:Modified platelet-rich plasma at different concentrations could promote the proliferation of dental pulp stem cells from deciduous teeth. The effects of 2%modified platelet-rich plasma and 10%fetal bovine serum on promoting the proliferation of dental pulp stem cells from deciduous teeth were similar. These results indicated that 2%modified platelet-rich plasma could promote the proliferation of dental pulp stem cells from deciduous teeth, and substitute for fetal bovine serum in the amplification of dental pulp stem cells from deciduous teeth in vitro.

Background Retina fixed flat-mount perfused by Evans blue (EB) is a common method for the evaluation of blood-retinal barrier (BRB).However,previous method is inconvenient for some laboratories because the retinal specimen can not be observed by gereral microscope rather than confocal laser scanning microscope after the fixation.Objective This study was to modify the preparing way of flat-mounted retina in order to obtain transparent specimen for the observation of rat retinal vessels and the evaluation of leakage under the ordinary fluorescence microscope.Methods Forty male SD rats were divided into the control group,diabetes mellitus (DM) 1-month group,DM 3-month group and DM 6-month group according to the random number table.Streptozotocinum (STZ) of 2％ dissolved in 0.05 mmol/L sodium citrate-hydrochloric acid buffer was intraperitoneally injected in SD rats to establish DM models,and the equal volume of solvent was injected in the same way in the control rats.One month,three months and six months after injection,EB of 30 g/L was injected via rat femoral vein in the dose of 45 mg/kg.Fifteen minutes after injection of EB,the rats were sacrificed and the retinas were isolated and cut radially to prepare the flat-mounted retinas in PBS immediately and then were dried till the specimens were transparent.The specimens were examined under the fluorescence microscope.The percentage of EB leakage was quantitatively calculated by IPP 6.0 software.All procedures were performed following approval of the institutional animal care and use committee of Tianjin Medical University.Results The retina morphology was normal in the control group,and EB filled the vessels,exhibiting the red fluorescence under the fluorescence microscope.Compared with the control group,retinal background fluorescence was enhanced slightly in the DM 1-month group,and focal leakage of the EB from capillaries and focal dilated vessels were found in the DM 3-month group,further,vascular caliber inequality,retinal hypoperfusion area and a larger number of hyperfluorescence areas were seen in the DM 6-month group.The percentage of leakage area was (0.05 ±0.02) ％,(0.27 ±0.06) ％,(1.17 ±0.18)％ and (4.77 ±0.66)％ in the control group,DM 1-month group,DM 3-month group and DM 6-month group,respectively,showing a significant difference among the four groups (F =795.800,P＜0.001),and the leakage area was obviously larger in the DM 3-month group and DM 6-month group than that in thecontrol group (q'=10.338,q'=43.475,both at P＜0.001).Conclusions Modified EB-perfused retinal wholemount method is easy and helpful for clear visualization of retinal vessel leakage induced by BRB breakdown in the diabetic rats under the common fluorescence microscope.

Objective To assess the value of color Doppler ultrasonogarphy in the diagnosis of subacute thyroiditis (SAT). Methods Sixty-eight patients of SAT and 30 patients with thyroid papillary carcinoma were included, and their imaging features were retrospectively reviewed. Results All the patients with SAT had either focal or diffuse hypoechogenicity of the thyroid lobes with rich blood supplying in the diseased region, among them 52 patients (76.47%, 52/68) had tenderness on palpation. Diffuse and focal lesions were found in 40 (58.82%, 40/68) and 28 patients (41.18%, 28/68). The boundary and shape of focal lesions had no diagnostic characteristics compared with those of thyroid papillary carcinoma. Punctate calcification and resistance index (RI) in the nodule were significant different between the SAT and thyroid papillary carcinoma (P＜0.05). Conclusion Color Doppler ultrasonography can display the features of SAT and is an effective method for the diagnosis of SAT.

Objective:To investigate the effect of modified plateletrich plasma(mPRP)on the osteogenic differentiation of stemcells from human exfoliated deciduous teeth(SHED).Methods:mPRP at 1%,2%,5%,10% and FBS at 10% were added to thecultured SHED of passage 4,respectively.The influence of mPRP on alkaline phosphatase(ALP)activity was evaluated using ALPkit.RUNX2 and osteocalcin mRNA expression in the treated cells were examined by realtime PCR.Results:mPRP enhanced ALPactivity in the SHED,and the effect of mPRP was more obvious at 2%.Treatment of the cells with 2% mPRP upregulated the mRNAexpressions of RUNX2 and osteocalcin.Conclusion:mPRP can promote the osteogenic differentiation of SHED.

Hemangioma, Cavernous ; Humans ; Pericardium ; pathology

Objective To study the inhibitory effect of verapamil and nicardipine on human scar fibroblast in serum-free culture and to compare the effectness of the two drugs.Methods We used MTT method to detect the effect of two drugs on human scar fibroblast proliferation:adding verapamil and nicardipine with different concentrations in the culture of fibroblasts which were in logarithmic growth phase (150,100,50,10,0μmol/L).After 24,72,and 120 h,we used MTT method to detect the cell proliferation,and converted the absorbance into growth inhibitory ratio.Results Verapamil and nicardipine showed the definite inhibition on the hypertrophic scar fibroblast (HSFB) and keloid fibroblast (KDFB) which were cultured in vitro.There was some difference in the action feature.In the earlier period,the effect of verapamil was powerful than that of nicardipine.With time,the effect did not reinforce.When fibroblast had been cultured for three to five days,the inhibition became weak.But nicardipine showed lasting inhibition on fibroblast proliferation.Conclusion Combination of verapamil with nicardipine may be a valuable method in the treatment of scar.

OBJECTIVE: To explore the clinical characteristics and genetic etiology of a child with Aicardi-Goutières syndrome 3 (AGS3). METHODS: Trio whole exome sequencing was carried out for the child and his parents, and candidate variants were verified by Sanger sequencing. To further clarify their pathogenicity, the crystal structure of the variants was simulated and analyzed, and the plasmid of variants was expressed in vitro. A literature search was also carried out to summarize the phenotypic and genetic characteristics of AGS3. RESULTS: The child was found to harbor novel compound heterozygous variants of the RNASEH2C gene, namely c.434G>T (p.Arg145Leu) and c.494G>C (p.Ter165Ser), which were inherited from his mother and father, respectively. Analysis of protein crystal structure suggested that the c.434G>T (p.Arg145Leu) variant may affect the stability of local structure, and in vitro experiments showed that this variant can lead to protein degradation. The c.494G>C (p.Ter165Ser) variant has destroyed the stop codon, resulting in prolonged variant. CONCLUSION The novel compound heterozygous variants of the RNASEH2C gene probably underlay the AGS3 in this child, which has enriched the phenotypic and mutational spectrum of this disorder.
Humans ; Child ; Mutation ; Autoimmune Diseases of the Nervous System/genetics* ; Nervous System Malformations/genetics*

Objective To build the lentiviral vectors of pigment epithelial derived factor (PEDF) gene,and investigate their expression in human umbilical cord mesenchymal stem cells (hUCMSCs).Methods The PEDF lentiviral vectors (LV-PEDF) were built by DNA recombination and confirmed by DNA sequencing.hUCMSCs were transfected by LV-PEDF with MOI 10,30,50,respectively.The transfection efficiency was observed under fluorescence microscope.Cell immunofluorescence,immunocytochemistry and real-time PCR methods were used for detecting the expression of PEDF and VEGF.Results The PEDF cDNA was sub-cloned into pCDH-CMV-MCS-EF 1-copGFP vector successfully.DNA sequencing analysis confirmed that PEDF gene sequence was exactly the same with that reported in GenBank.pCDH-PEDF infected cells could show green fluorescence under fluorescence microscope.The transfection efficiency was 72.1％ in PEDF-MSCs.Immunofluorescence and immunochemical staining confirmed that PEDF protein was overexpressed in hUCMSCs.The relative expression of PEDF mRNA in experimental group and control group was (0.170±0.028) and (0.015 ± 0.007) respectively by RT-PCR,the difference was statistically significant (P＜0.00 1).The relative expression levels of VEGF mRNA in the two groups were (0.265 ± 0.022) and (0.285 ± 0.049),respectively,with no significant difference (P＞0.05).Conclusions We successfully built a lentivius vector carrying PEDF gene and obtained hUCMSCs with overexpressed PEDF.