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BACKGROUND: When the teeth are separated from the alveolar fossa, the periodontal membrane breaks, and the residual periodontal membrane on the avulsed tooth root surface changes from three-dimensional to two-dimensional, thus losing the role of scaffold, and leading to root bone adhesion after replantation of avulsed tooth. How to develop a three-dimensional sustained-release scaffold material that can adhere to the root surface with a certain thickness and strength is one of the key factors for successful regeneration of avulsed tooth periodontal membrane. OBJECTIVE: To construct a three-dimensional periodontal biomimetic membrane that can adhere to the avulsed tooth root surface and allow sustained-release of growth factors. METHODS: Poly(lactic-co-glycolic acid) (PLGA) membrane was prepared using electrospinning technique. The effects of dichloromethane and dimethylformamide mixture, hexafluoroisopropanol, and trichloromethane on electrospun membrane were investigated to obtain the optimal electrospinning solvent. Chitosan microspheres were prepared by electrospray and ion cross-linking techniques. The effects of molecular weight (50, 000, 100, 000) and mass concentration (10, 20 g/L) of chitosan, sodium tripolyphosphate concentration (2%, 5%, 10%) and voltage (14, 28 kV) on chitosan microspheres were studied to screen the optimum parameters. Chitosan microspheres containing stromal cell-derived factor-1 (optimal parameter design) were constructed. The release rate of stromal cell-derived factor-1 alpha in vitro was determined. First, the root surface of teeth was wrapped with electrospun PLGA membrane, then chitosan microspheres were dripped on the surface, and finally the surface was wrapped with a thin layer of electrospun PLGA. Thus, PLGA-chitosan-PLGA biomimetic membrane was constructed. RESULTS AND CONCLUSION: Electrospun PLGA membrane prepared with hexafluoroisopropanol as electrospinning solvent had the smallest average diameter and the largest porosity. When the relative molecular weight of chitosan was 50, 000 and the mass concentration was 20 g/L, the size of chitosan microspheres was basically the same, and the average diameter was 366. 6 μm. In addition, chitosan microsphere had good monodispersity, fullness, and stability. Chitosan microspheres formed under 28 kV voltage and were more in line with the requirements of biomimetic membrane for avulsed tooth. The surface of microspheres prepared by 5% sodium tripolyphosphate had medium-sized pores, which are most conducive to clinical periodontal membrane regeneration. Chitosan microspheres can sustainably release stromal cell derived factor 1alpha for about 1 month. In this study, we constructed a three-dimensional PLGA-chitosan-PLGA periodontal biomimetic membrane that can adhere to the avulsed tooth root surface and allow sustained-release of growth factors and obtained the optimal parameters of constructing the periodontal biomimetic membrane. Based on the PLGA-chitosan-PLGA periodontal biomimetic membrane, the effect and mechanism of tissue engineering on replantation of avulsed tooth can be further studied.
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Objective:To explore the application and treatment efficacy of less invasive surfactant administration (LISA) and nasal high-frequency oscillation ventilation (nHFOV) in very low and extremely low birth weight preterm infants with neonatal respiratory distress syndrome (NRDS).Methods:A total of 85 very low and extremely low birth weight preterm infants with gestational age ranging between 27-32 weeks who were diagnosed with NRDS in the Second Affiliated Hospital of Zhengzhou University from July 2018 to October 2019 were enrolled.After being stratified by gestational age of >27-29 weeks, >29-30 weeks, >30-31 weeks, >31-32 weeks, the neonates were divided into the LISA group (40 cases) and the intubation-surfactant-extubation (INSURE) group (45 cases) by the random envelope method.The LISA group was subdivided into the continuous positive airway pressure (CPAP) group (25 cases) and the nHFOV group (15 cases) by the same method.The patients in the INSURE group were infused with pulmonary surfactant (PS) through the endotracheal tube under positive airway pressure, and then treated with CPAP after extubation.The patients in the LISA group were first treated with CPAP and injected with PS through the gastric tube.After removing the gastric tube, the patients in the CPAP group were given CPAP-assisted ventilation, while the patients in the nHFOV group were given nHFOV-assisted ventilation or mechanical ventilation if nHFOV-assisted ventilation failed.The feasibility of LISA technology and nHFOV was observed, and the adverse reactions, mechanical ventilation, oxygen duration, hospital stay and the incidence of NRDS complications in different groups of the patients were compared.Results:(1) The mechanical ventilation rate (5.0% vs.22.2%), the incidence of broncho-pulmonary dysplasia (BPD) (20.0% vs.42.2%) and the incidence of periventricular leukomalacia (PVL) (12.5% vs.42.2%) in the LISA group were significantly lower than those in the INSURE group (all P<0.05). There were no statistically significant differences in total oxygen duration, hospitalization duration, intraventricular he-morrhage (IVH), retinopathy of prematurity (ROP), and necrotizing enterocolitis (NEC) between the LISA group and the INSURE group (all P>0.05). (2) There was no significant difference in adverse reactions between the LISA group and the INSURE group as well as between the CPAP group and the nHFOV group (all P>0.05). (3) The younger the gestational age at birth, the higher the incidence of NRDS complications.Patients in the LISA group had a lower incidence of NPDS complications than patients of the same gestational age in the INSURE group, but the diffe-rence was not statistically significant (all P>0.05). (4) There was no significant difference in the mechanical ventilation rate and the incidence of BPD, IVH, PVL, NEC and ROP complications between the CPAP group and the nHFOV group (all P>0.05). Conclusions:In the treatment of very low and extremely low birth weight preterm infants with NRDS at the gestational age of 27-32 weeks, LISA technology is a safe and effective PS delivery method, which can reduce the mechanical ventilation rate and the incidence of BPD and PVL.The nHFOV can be used as an initial model for respiratory support of NRDS preterm infants with very low and ultra-low birth weight.LISA combined with nHFOV is applicable to the treatment of preterm infants with NRDS.
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Objective o evaluate the association between IL-28B ( rs12979860 ) polymorphism andantiviraltherapeutic effectbydetecting the genotype of interleukin-28B( IL-28 B) in patients with hepatitis C ( HCV ) .Methods Of total 1153 HCV patients, 303 diagnosed with CHC had been treated with pegylated interferon plus ribavirin for 24-48 weeks.IL-28B ( rs12979860 ) was genotyped by two-color fluorescent TaqMan assay.Results Among 1153 patients, CC, CT and TT genotype frequencies of IL-28B rs12979860 are 83.26%, 16.22%and 0.52%respectively.The results of HCV genotypingof 580 in 1153 cases, the frequencies of 1b, 2a and their non-1b/2a type are 63.45%, 35.00%and 1.55%respectively;In 303 CHC patients with clear medical history, the proportion of SVR was71.98% in patients with CC genotype and 16.90%in those with either the CT or TT genotypes.Logistic regression model was adopted to analyze the association of rs12979860 with SVR while adjusting for age, gender, viral load and HCV GT factors.Populations carrying combined genotype ( CT +TT) are making it harder to get SVR compared with those with CC genotype (OR, 95%CI:11.10,5.35-23.04;P<0.000 1).The percentages of SVR in HVC patients with 1b and 2a genotypeare 48.02% and 81.19% respectively.there is a statistically significant difference between these subgroups (χ2 =30.639,P<0.000 1).Conclusion IL-28B rs12979860 genotype is closely related to SVR in CHCpatients.Patients with CC genotype have a higher virus sustained response rate than those carrying CT or TT genotype.The SNP , rs12979860, might be applied as a predictor of clinical antiviral efficacy in the furture.
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Objective: To study the phenotypes and functions of dendritic cells (DCs) derived from peripheral blood monocytes of chronic hepatitis B (CHB) patients with different traditional Chinese medicine (TCM) syndrome types, and to explore the relationship between TCM syndrome type and DC functions. Methods: Sixty CHB patients were included in this study. All the CHB patients were divided into spleen deficiency and liver stagnation, spleen deficiency and dampness-heat and deficiency of both spleen and kidney groups according to TCM syndrome diagnosis standard. There were 20 cases in each group, and ten healthy people were included as normal control. The volunteer's peripheral blood was collected for monocyte separation, biochemical test and hepatitis B virus DNA loads detection. DCs were induced and isolated from peripheral blood monocytes, and then the expressions of surface markers CD80, CD86, CD1a and HLA-DR were detected by flow cytometric analysis method. Interleukin-10 (IL-10) production of the DCs was quantified by enzyme-linked immunosorbent assay. Results: The proliferation of DCs in the CHB patients was slower than that in the healthy volunteers (P<0.05). The expressions of DC surface molecules such as CD80, CD86, and CD1a were obviously decreased in the CHB patients as compared with those in the healthy volunteers (P<0.05). More over, expressions of DC surface molecules were different among CHB patients with different TCM syndrome types. The positive expressions of CD80, CD1a, and HLA-DR in the CHB patients with spleen deficiency and liver stagnation were obviously higher than those in the CHB patients with deficiency of both spleen and kidney (P<0.05), and the CD1a expression in the CHB patients with spleen deficiency and dampness-heat was higher than that in the CHB patients with deficiency of both spleen and kidney (P<0.05). In DC culture supernatant, the IL-10 concentration of the CHB patients with deficiency of both spleen and kidney was higher than that of the CHB patients with spleen deficiency and liver stagnation (P<0.05), and the IL-10 concentrations of the CHB patients with different TCM syndrome types were higher than that of the healthy volunteers (P<0.05). Conclusion: During the pathogenic course of CHB, the phenotypes and functions of DCs are different in CHB patients with different TCM syndrome types. It suggests that there is a correlation between TCM syndrome type and body immunity function.