1. Analysis of liquid-solid interaction during three-dimensional printing of medical amorphous calcium phosphate
Chinese Journal of Tissue Engineering Research 2021;25(16):2548-2553
BACKGROUND: Based on excellent hydration ability, the materials for repairing bone defects could be fabricated by three-dimensional printing from amorphous calcium phosphate simply with pure water as adhesive solution; and more importantly, the printed products could be directly used in clinical medicine without high temperature sintering, so amorphous calcium phosphate fits well with technical features of three-dimensional printing. OBJECTIVE: To prepare bone repair materials of amorphous calcium phosphate with mechanical property and printing accuracy to meet practical application requirements by three-dimensional printing. METHODS: Amorphous calcium phosphate used as prototyping powder was prepared by coprecipitation method, and then the viscosity and surface tension of the deionized water as adhesive solution were adjusted by thickening agent and leveling agent, respectively. Afterwards, the three-dimensional printing productions for repairing bone defects were fabricated, and the effects of the viscosity and surface tension of adhesive solution on the forming of droplet, liquid-solid interaction and the mechanical property as well as printing accuracy of three-dimensional printing productions were investigated. RESULTS AND CONCLUSION: By investigating the forming of droplet and liquid-solid interaction, the optimal physicochemical parameters of the adhesive solution were obtained. The viscosity and surface tension of the optimal adhesive solution were 8.0 × 10-3 Pa•s and 40.0 × 10-3 N/m separately, and at this point, not only droplet could form stably and controllably (Z=5.06), but also it smoothly struck the powder layer during spraying (K=14.29), and then it infiltrated into the powder layer uniformly and spread in time (We=36.86). The corresponding three-dimensional printing production has good mechanical properties (compressive strength is 30.4 MPa), high printing accuracy (forming error is 0.9 mm), and a large number of pores indicating good bone conductivity, which partially meets clinical demands of repairing bone defects.
2. Enzymatic synthesis of three kinds of galactose-cholesterol ligands and their structure-activity relationship with liver targeting
Chinese Traditional and Herbal Drugs 2018;49(16):3804-3814
Objective To construct three kinds of doxorubicin liposomes modified with cholesterol-galactose ligand by lipase-catalyzed method and compare their characteristic of pharmacokinetics and tissue distribution in vivo. Methods Three types of cholesterol-galactose ligands, CHS-C8-GalNAc, CHS-C8-GAL, and CHS-C8-LA were synthetized by lipase-catalyzed method in nonaqueous phase. The structure characterizations of products were obtained by MS and NMR. Conventional liposomes (CL DOX) and ligand-coupled liposomes (NGal-LP DOX, Gal-LP DOX, and LA-LP DOX) were prepared by thin film dispersion-ammonium sulphate gradient method. Structure-activity relationship between asialoglycoprotein receptor (ASGPr) and the chemical structure of the glycolipids was explored through the pharmacokinetics and tissue distribution parameters of ligand-coupled liposomes in vivo. Results The desired compounds with a high yield of above 90% were confirmed by MS and NMR. The liposomes average size was lower than 90 nm, polymer dispersity index was lower than 0.1, encapsulation efficiency was greater than 99%, leakage rat was lower than 5% with 24 h, and zeta potential closed to zero. The affinity of the three ligand molecules to liver was the following order: CHS-C8-GalNAc > CHS-C8-LA > CHS-C8-Gal. However, only the liposomes modified with CHS-C8-GalNAc could significantly be inhibited by the preinjection of asialofetuin for hepatic uptake rate (P < 0.01), but the liposomes modified with CHS-C8-LA and CHS-C8-Gal could not be inhibited by the preinjection of asialofetuin for hepatic uptake rate (P > 0.05). Conclusion The ligand with N-acetylgalactosamine residue showed high targeting efficiency for hepatocytes, while the ligand with D-galactose (Gal) or lactitol residue could competitive bind with Gal particle receptor on kupffer cells.
3. Lipase-catalyzed construction of glucose-modified brain targeting liposomes with paclitaxel and research on its optimized preparation process
Chinese Traditional and Herbal Drugs 2016;47(11):1867-1874
Objective: To synthesize brain targeting lipid material [(5-cholesten-3β-yl) (D-glucopyranose-6) sebacate, CHS-SE-GLU] by lipase as catalyst in nonaqueous phase and optimize the preparation technology and formulation of CHS-SE-GLU-modified liposomes. Methods: CHS-SE-GLU was synthesized from CHS-SE prepared in previous work and D-glucose using lipase Novozym 435 in acetone. The structure characterization of the products is obtained by MS and NMR. The CHS-SE-GLU-modified paclitaxel-loaded brain targeting liposomes (GLU-PTX-LP) were prepared by thin film dispersion method. Single factor evaluation was applied to optimizing its preparation technology and formulation. Results: CHS-SE-GLU was confirmed by MS and NMR as target products. The optimal formulation and technology of GLU-PTX-LP were as follows: HSPC as membrane material, the ratio of HSPC to PTX was 0.1, the ratio of CHS to HSPC was 0.5, the dosage of DSPG-Na was 2.5%, hydration time was 0.5 h, and hydration temperature was 50 ℃. Three batches of samples were prepared by optimum preparation process and the average encapsulation efficiency was (93.62±1.34)%, (93.75±1.77)%, (92.04±1.50)%; The average particle size was (89.56±1.35), (92.05±3.42), (104.91±3.71) nm; And the average Zeta potential was (-25.21±0.27), (-26.43±0.44), (-25.17±0.65) mV, respectively. Conclusion: Lipase-catalyzed method for the preparation of brain targeting lipid material is simple and environment friendly with high yield. The entrapment efficiency, particle size, and stability of brain targeting drug-loading liposomes modified by CHS-SE-GLU all meet the requirement, which shows good application prospect.
4. Lipase-catalyzed synthesis of cholesteryl vinyl hemi-sebacate for selective targeting of liposomes in organic media
Chinese Traditional and Herbal Drugs 2013;44(23):3289-3295
Objective: To synthesize cholesteryl vinyl hemi-sebacate from cholesterol and divinyl sebacate in non aqueous phase. Methods: TLC, MS, and NMR were used to identify the structure of production; the technological conditions of enzymatic esterification were determined through orthogonal test. Results: The best condition: isooctane 5 mL, reaction temperature 35°C, reaction time 24 h, Candida rugosa Lipase 10 mg/mL, molar ratio of cholesterol to divinyl sebacate 1:6. Conclusion: The highest esterification rate is above 95%.
5.Effect of Family Rehabilitation Plan on Motor Function of Stroke Patients with Hemiplegia
Jun-hua WANG ; Bin NIE ; Yue LIU
Chinese Journal of Rehabilitation Theory and Practice 2006;12(8):677-678
ObjectiveTo observe the effect of family rehabilitation plan (FRP) on motor function of stroke patients with hemiplegia.Methods64 patients were randomly divided into the FRP group (32 cases) and control group (32 cases). The patients in the FRP group critically followed the schedule and activities scheduled on FRP and were assessed and guided in out-patient department every two weeks. The patients in the control group made schedule and carried on activities by themselves. Motor function was assessed with Fugl-Meyer Assessment (FMA) and modified Barthel index (MBI) respectively.ResultsMotor scores of the patients in two groups significantly increased after treatment ( P<0.001), and that of the FRP group was significantly better than that of the control group ( P<0.001).ConclusionThe FRP can significantly improve motor function of stroke patients with hemiplegia.
6.The relevancebetween genetic polymorphismof NR3C1andaggressive behavior in Yunnan Han population
Aiting NIE ; Liping HU ; Yang CHEN ; Hua FU ; Xiufeng ZHANG ; Min RAO ; Wenkai SONG ; Shengjie NIE
Chinese Journal of Forensic Medicine 2017;32(2):145-149
Objective To study the correlation between the polymorphisms of NR3C1 gene and aggressive behavior in Yunnan Han population.Methods Five SNPs of the NR3C1 gene (rs6190,rs6191,rs6198,rs41423247 and rs56149945) were genotyped in 194 unrelated prisoners who committed violent-crimes and 301 healthy controls using improved Multiplex-ligase-detection reaction(iMLDR) method,and the data were statistically analyzed with the SPSS19.0soflware and PHASE2.1platform.Results Single locus analysis showed that the allelic distribution of rs6191and rs41423247did not show significant differencesbetween the control groupand the aggressive-behavior group as well as the robbery sub-group and intentional injury sub-group.However,significant difference was foundin the rs41423247 genotype distribution betweencontrol groupand robbery sub-group (p=0.048).In addition,there were no significant differences for the four haplotypes between the control group,the attack group,the robbery subgroup and the intentional injury subgroup.Conclusion These findings indicate that rs41423247 polymorphism of the NR3C1gene might play a role in susceptibility to aggressive behavior and rs6191 polymorphismmay not be correlated withaggressive behavior.
8.DNA methylation in ?-thalassemia by oligonucleotide microarray
Tian GAO ; Zhiqing LIANG ; Yanli NIE ; Hua HU
Journal of Third Military Medical University 2003;0(24):-
Objective To search and analyze the DNA methylation-related genes of ?-thalassemia by oligonucleotide microarray in order to explore a new method for early diagnosis of ?-thalassemia.Methods The cord blood samples of 2 children with ?-thalassemia and 2 health children were detected by a chip containing human DNA methylation 30 178 oligonucleotide probes.The chip results were verified by the methods of methylation-specific PCR (MSP) and real-time PCR.The statistical significance of differentially expressed genes was found on non-supervised clustering (Hierarchical clustering).Results A total of 209 genetic differences (ratio≥2.0 or≤0.5) were showed by 2 groups of chips,and of them 113 genes were up-regulated and 96 genes were down-regulated.The results showed that the methylation-related gene erythroblastic leukemia viral (v-erb-a) was of hypermethylation compared with the normal blood.Conclusion A large number of differentially expressed genes are screened out by the technology of High-throughput DNA methylation of the gene chip in thalassemia.The DNA methylation-related gene of v-erb-a is of hypermethylation in thalassemia.Our methods offers a new idea and approach for prenatal diagnosis for thalassemia by the DNA methylation-related microarray.
9.THE POSTNATAL DEVELOPMENT OF THE BRAIN STEM PROJECTIONS TO THE LUMBOSACRAL SPINAL CORD OF RAT——A HRP STUDY
Xiangting ZHOU ; Zhengming NIE ; Shanjun TANG ; Shengqiong LIANG ; Hua ZHANG
Acta Anatomica Sinica 1953;0(01):-
The postnatal development of the efferent projections to the lumbosacral spinal cord from the brain stem of rats were studied with HRP retrograde transport method. Fifty per cent solution of HRP was slowly injected into the intumescentia lumbalis on its right side in 18 albino rats from postnatal 1-35 days. The HRP labelled cells were found in the following nuclei:1. Of the midbrain: the nucleus ruber, substantia nigra and nucleus raphe dorsalis.2. Of the pons: the nucleus reticularis pontis oralis, nucleus reticularis pontis caudalis, locus coeruleus, nucleus subcoeruleus, nucleus raphe magnus, nucleus vestibularis lateralis, and nucleus vestibularis medialis.3. Of the medulla oblongata: the nucleus raphe obscurus, nucleus raphe pallidus, nucleus reticularis ventralis, nucleus reticularis gigantocellularis, nucleus reticularis lateralis, nucleus tractus spinalis nervi trigemini, nucleus commissuralis (Cajal), nucleus prepositus hypoglossi, and nucleus gracilis.The number of the labelled cells in the above nuclei increased steadily with age. The results of present study showed that there was a postnatal developmental process in the efferent projections from the brain stem to the lumbosacral cord. The maturity of the projections from ruber nucleus and locus coeruleus were later than those of the vestibulospinal and reticulospinal tracts. The postnatal developmental process of the brain stem projections to the lumbosacral spinal cord were completed by one month after birth.
10.Experience of improving safety in radical operation for gastric cancer
Zhanqiang HUA ; Jianwei BI ; Mingming NIE ; Xuguang HUANG
Chinese Journal of Postgraduates of Medicine 2015;38(z1):40-42
Objective To explorer the safety of D2 lymphadenectomy in open distal gastrectomy for distal gastric cancer with the surgical approach from bottom to top,from left to right and from surrounding to middle.Methods 100 advanced distal gastric cancer patients selected from General Surgery Department of Chang Hai Hospital from December 2012 to November 2013 were analyzed retrospectively.All the patients were performed D2 lymphadenectomy in open distal gastrectomy with surgical approach from bottom to top,from left to right and from surrounding to middle.The operation time,amount of bleeding,the number of lymph nodes,postoperative complications and follow-up observation were recorded.Ruselts All patients had successful operation.The operation time was 90 to 190 mins,the average (125.00 ± 21.43) mins;intraoperative blood was 90 to 400 ml,the average (178.00 ± 73.74) ml;number of lymph node dissection was 17 to 41,the average (26.00 ± 6.72).One patient suffered from abdominal hemorrhage,recoverd and discharged after conservative treatment.Conclusions Surgical approach from bottom to top,from left to right and from surrounding to middle can improve the safety of D2 lymphadenectomy for distal gastric cancer.