To investigate the anatomic feature of the posterior hip joint capsule and its distributional difference of collagen fibers and to probe the optimization of the capsulotomy which can reserve the best strength part. Methods Ten adult cadaver pelvises (6 males and 4 females, aged 28-64 years) fixed with formal in were used. Ten right hips were used for anatomical experiment of hip joint capsule. The posterior hip joint capsules were divided into 3 sectors(I-III sectors ) and 9 parts (IA-C, IID-F, IIIG-I). The average thickness of each part was measured and the ischiofemorale l igaments were observed. Five capsules selected from ten left hips were used for histological experiment. The content of collagen fibers in sector I and sector II was analyzed by Masson’s staining. Two fresh frozen specimens which were voluntary contributions were contrasted with the fixed specimens. The optimal incision l ine of the posterior capsule was designed and used. Results The thickness in the posterior hip joint capsule [IA (2.30 ± 0.40), IB (4.68 ± 0.81), IC (2.83 ± 0.69), IID (2.80 ± 0.79), IIE (4.22 ± 1.33), IIF (2.50 ± 0.54), IIIG (1.57 ± 0.40), IIIH (2.60 ± 0.63), IIII (1.31 ± 0.28) mm] had no uniformity (P lt; 0.01). The IIIG part and the IIII part were thinner than the IB part and the IIE part (P lt; 0.01). Two weaker parts located at obturator externus sector (sector III), the ischiofemorale l igament trunk went through two thicker parts (IB and IIE). The distribution of the collagen fibers in sector I and sector II(IA 20.34% ± 5.14%, IB 48.79% ± 12.67%, IC 19.87% ± 5.21%, IID 17.57% ± 3.56%, IIE 46.76% ± 11.47%, IIF 28.65% ± 15.79%) had no uniformity (P lt; 0.01). The content of collagen fibers in IB part and IIE part were more than that of other parts (P lt; 0.01). There were no statistically significant difference in the distribution feature of the thickness and the ischiofemorale l igaments between the fresh frozen specimens and the fixed specimens. The optimal incision l ine C-A-B-D-E of the posterior capsule was designed and put into cl inical appl ication. The remaining capsular flap comprise the most of the ischiofemorale l igament trunk and the part of gluteus minimus. Conclusion Although enhanced posterior soft tissue repairin total hip arthroplasty was investigated deeply and obtained great development, but the postoperative dislocation rate was not el iminated. It is significant for optimizing the capsulotomy to reserve the best strength part of the posterior capsule and to bring into full play the function of the ischiofemorale l igaments.
Objective To analyze the molecular composition of type IV collagenous fibres in internal limiting membrane (ILM) of human retina. Methods ILM was surgically removed from retina and identified under phase-contrast and transmission electron microscopes. Monoclonal antibodies against different αchains (α1-α6) of type IV collagen were immuno-localized. Results α3, α4, and α5 chains of type IV collagen were immuno-localized in human retinal ILM, while α1, α2, and α6 chains could not be immuno-localized. Conclusion Type IV collagenous fibres in human retinal ILM are composed of α3, α4, and α5chains. (Chin J Ocul Fundus Dis，2004，20：364-368)
Objective To investigate the effect of hepatitis C virus (HCV) F protein on proliferation and collagen expression of hepatic stellate cells. Methods After pcDNA3.1-f plasmid containing HCV f gene or empty pcDNA3.1 plasmid was transfected hepatic stellate cells LX2 by liposome, LX-f or LX-p cells were obtained by G418 screening. The proliferation of LX-f or LX-p cells was analyzed by MTT, and the contents of collagen type Ⅰand Ⅲ secreted by LX-f or LX-p cells were detected by ELISA. Results After 24 h cultivation, the proliferation rate of LX-f cells was higher than that of LX-p cells at each time point （Plt;0.01）. After 48 h cultivation, the contents of collagen typeⅠand Ⅲ secreted by LX-f were (25.89±0.42) ng/ml and (18.21±0.49) ng/ml, which was significantly higher than those of LX-p cells 〔(22.65±0.49) ng/ml and (15.29±0.62) ng/ml〕, Plt;0.01. Conclusion HCV F protein is able to promote proliferation of hepatic stellate cells, and up-regulate the excretion of collagen type Ⅰand Ⅲ in those cells, which induces hepatic fibrosis.
Objective To study the allograft effect of two kinds of tissue engineered oral mucosa lamina proprias on skin fullthickness wounds. Methods The cultured Wistar rat oral mucosa fibroblasts (OMF) were incorporated into collag en or chitosancollagen to construct the tissue engineered oral mucosa laminaproprias, and then the OMFs were labeled with BrdU. The fullthickness round skin defects were made with a round knife (diameter, 0.8 cm) on the backs of 36 Wistar rats (2125 weeks old), which were divided into 2 experimental groups: the fibroblastpopulated collagen lattices (FPCL) group (grafted by FPCLs) and the fibroblastpopulated chitosan collagen lattices (FPCCL) group (grafted by FPCCLs), and the control group (only covered with gauges). All the wounds were observed by the naked eyes or the light microscope, and were measured 4, 7, 14, and 21 days postoperatively. Results There were no infection during the wound healing period. At 7 days after the grafting, the wounds in the 3 groups were covered by scab and/or gauze; at 14 days, the gauze and scab on the wounds in the three groups were all replaced by the new epidermis naturally except one scab each in the FPCCL group and the control groups,which was replaced at 17 days.All the centers of the new epidermis were measurable as the pink red points. At 21 days, all the new skins were smooth without hairs, and their color was similar to the normal one. At 4, 7, and 14 days,there was an indication that the wound diameters became significantly smaller in the three groups; but after the 14th day, there was no significant indication of this kind. At 7 days, the wound diameter in the FPCL group was significantly smaller than that in the FPCCL group and the control group (Plt;0.01). Under the lightmicroscope, at 4 days postoperatively, the decayed tissue on the surfaces of the recipient wounds in the FPCL group and the FPCCL group was separated from the lower granular tissue in which there were many inflammatory cells, fibroblasts, and new vessels. There was a similar-phenomenon in the control group. Each skin wound in the three groups was only partly keratinocyted at 7 days postoperativel y. The recipient wounds were wholly keratinocyted with when rete ridges observed at 14 and 21 days, but in the control group the wounds were keratinocyted with no rete ridges. Fibers in the new dermis were thin. The OMFs with Brdu appeared in the granular tissue and new dermis at 4, 7, 14, and 21 days postoperatively, which could be illustr ated by the immunohistochemical staining. The positive OMFs and the granular tissue joined in the repair of the skin defe cts without any allergic reaction during the period of the wound healing. Conclusion The oral mucosa fibroblasts as the new seed cells can join i n the repair of the skin defects effectively and feasibly. The fibroblastpopul ated collagen lattices and the fibroblastpopulated chitosan collagen lat tices can repair skin defects effectively and feasibly, too. And the quality of the new skins was better in the two experimental groups than in the control group.
Objective To investigate the influence of lipopolysaccharide(LPS) on the proliferation and collagen synthesis of normal human skin fibroblasts so as to elucidate its relation with skin wound healing. Methods Fibroblasts wereisolated and cultured in vitro, and then exposed to different doses of LPS(0.005, 0.010, 0.050, 0.100, 0.500, and 1.000 μg/ml) from E.coli055∶B5 respectively. Then the absorbance (A) value of fibroblasts was determined with the colorirneteric thiazolylblue (MTT) assay, and the cell number was counted under inverted phase contrast microscope from the 1st day to the 9th day after LPS administration, and collagen synthesis of fibroblasts in culture medium was measured with the method of pepsin digestion after incorporation of 3Hproline into stable, single-layered, confluent fibroblasts at 7 days after LPS administration. Results Compared with control group, A value increased with the increasing concentration of LPS (0.005 μg/ml 0.500 μg/ml) and LPS of 0.100 μg/mlgroup had the best effect. The difference was remarkable from the 5th day to the 9th day(P＜0.05). A value decreased when challenged with the LPS of 1.000 μg/ml and the difference was remarkable from the 3rd day to the 9th day(P＜0.05). Cell number increased with theadministration of LPS of different concentrations (0.005 μg/ml 0.500 μg/ml) and LPS of 0.100 μg/mlgroup had the best effect. The difference was remarkable from the 1st day to the 6th day(P＜0.05). Cell number decreased remarkably when challenged with LPS of 1.000 μg/ml and the difference was remarkable from the 2nd day to the 9th day(P＜0.05). Collagen synthesis increased when challenged with LPS of different concentrations (0.005 μg/ml 0.500 μg/ml) and the 0.100 μg/ml group had the best effect. However, when the dose of LPS reached 1.000 μg/ml, it inhibited collagensynthesis. Conclusion LPS could promote the proliferation andcollagen synthesis of fibroblasts within a certain range of low doses, but over-high dose ofLPS might inhibit the proliferation and collagen synthesis of fibroblasts, suggesting that LPS of certain concentrations might contribute to wound healing, while excessive LPS has negative effect on wound healing.
Objective To introduce the development of the collagen materials in drug release and tissue engineering. Methods Literature review and complex analysis were adopted. Results In recent years, some good progress hasbeen made in the studies of collagen, and study on collagen-based materials has become an investigative hotspot especially in tissue engineering. Some new collagen-based drug delivery andengineered materials have come into clinically-demonstrated moment, which willpromote their clinical applications in tissue repairs.ConclusionCollagen has been considered a good potential material in drug release, especially in the tissue-engineering field. To give collagen new characters we should pay more attention to grafting with different function branches through chemistry technique in the future work, except- moderate cross-linking treatment or commingling withother nature or synthesized macromolecules.
Objective To explore a novel nanometer biomaterial which could induce the regeneration of tooth tissues intell igently, and to evaluate the feasibil ity of using this kind of biomaterial as the scaffold for tooth tissue engineering by investigating the role it plays in tooth tissue engineering. Methods The scaffold for tooth tissue engineering containing recombinant human bone morphogenetic protein 2 (rhBMP-2) was prepared by mixing nanoscale β tricalcium phosphate (β-TCP)/collagen particles. Forty-six 8-10 weeks old specific pathogen free Sprague Dawley (SD)rats, including 34 females and 12 males, weighing 250-300 g, were involved in this study. Tooth germs were removed under a stereomicroscope from the mandible of newborn SD rat, then digested and suspended. Scanning electronic microscope (SEM), adhesion rate of cells, and MTT assay were used to evaluate the effects of the scaffold on the tooth germ cells cultured in vitro. The tissue engineered tooth germ which was constructed by tooth germ cells and scaffold was transplanted under SD rat’s kidney capsule as the experimental group (n=12); the tooth germ cells (cell-control group, n=12) or scaffold without cells (material-control group, n=4) were transplanted separately as control groups Specimens were harvested to perform general and histological observations at 4 and 8 weeks after transplantation. Results β-TCP/collagen showed a loose and porous appearance with soft texture and excellent hydrophil icity. Tooth germ cells grew well and could attach to the scaffold tightly 3 days after coculture. The adhesion rates of tooth germ cells were 27.20% ± 2.37%, 44.52% ± 1.87%, and 73.81% ± 4.15% when cocultured with scaffold for 4, 8, and 12 hours, respectively. MTT assay showed that the cell prol iferation status of experimental group was similar to that of the control group, showing no significant difference (P gt; 0.05). Some white calcified specimens could be harvested at 4-8 weeks after transplantation. At 4 weeks after transplantation some typical structures of dental cusp and enamel-dentin l ike tissues could be seen in the experimental group. Enamel-dentin l ike tissues also formed in some specimens of cell-control group, but they arranged irregularly. At 8 weeks after transplantation the enamel-dentin l ike tissue of experimental group exhibited a mature appearance and organized structure in comparison with that at 4 weeks. And mature enamel or dentin l ike tissue also could be seen in cell-control group. In contrast, there was no enamel or dentin l ike tissue in material-control group at 4 or 8 weeks after transplantation. Conclusion rhBMP-2 decorated β-TCP/collagen scaffold has good biocompatibil ity and can be used as a novel nanometer biomaterial, so it is a good choice in scaffolds for tooth tissue engineering.
Objective To investigate the influence of the exogenouscollagen on the function of cells in construction of artificial biotendon.Methods Three materials including human hair, carbon fiber(CF) and polyglycolic acid (PGA) were combined with exogenous collagen and co-cultured with standard transferred human embryonic tenocytes at a concentration of 3×106/mm3 in vitro. The cell number and morphology were observed under inverted microscope and scanning electron microscope after 2 hours, 3 days and 5 days.Results In the artificial biotendon combined with collagen, the cells concentrated around the materials and the cells adhering to the materials turned into round after 2 hours. After 3 days, the adhering cells increased. After 5 days, the shape of the cells changed from round to spindle.ConclusionExogenous collagen will facilitate the cells to adhere onto materials and proliferate.
Objective To investigate the effects of simvastatin on the collagen synthesis of rat pulmonary arterial smooth muscle cells ( PASMCs ) induced by hypoxia. Methods Under hypoxic condition, rat PASMCs were cultured with different concentrations of simvastatin. Collagen synthesis of PASMCs with or without simvastatin were measured by 3H-proline incorporation assay. The mRNA expression of TGF-β1 and the contents of super oxide dismrtase ( SOD) ,malondialdehyde ( MDA) in mediumwere also measured. Results The incorporation data of 3H-TdR in the hypoxia group was significantly increased as compared with that in the control group ( P lt;0. 01) , and simvastatin significantly reduced the incorporation data of 3H-TdR induced by hypoxia. The expression of TGF-β1 mRNA in the hypoxia group was significantly increased as compared with that in the control group ( P lt; 0. 01 ) , and simvastatin could significantly inhibited hypoxia-induced expression of TGF-β1 mRNA in a dose-dependent manner. Compared with the hypoxia group, the expression of TGF-β1 mRNA decreased by 55% in simvastatin( 10 - 6mol /L) group ( P lt; 0. 01) , and by 70% ( P lt; 0. 01) in simvastatin ( 10 - 5mol /L) group. Compared with the control group, the activity of SOD was reduced and the contents of MDA were increased significantly in the hypoxia group. Simvastatin can increase the activity of SOD and reduced the content of MDA in a dose-dependent manner. Conclusions Simvastatin can decreases collagen synthesis of PASMCs. This effect might be explained that simvastatin can reduce lipid peroxide and expression of TGF-β1 mRNA.
Objective:To detect collagen I synthesis activity in the vitreous of PVR induced by macrophages in rabbits. Methods:PC Ⅲ (Procollagen Ⅲ ) concentrations were measured by radioim- munoassay in the vitreous samples of 14 rabbit eyes with experimental PVR and 14 control eyes. Results:The mean PC Ⅲ concentration on the 7th day after macrophage injection as 257.58mu;g/L(range,236.04~266.88mu;g/L,n= 4)and significantly increased on the 14th day later. On the 28th day the mean concentration of PC Ⅲ as 912.23mu;g/L (range, 881.36~943.10mu;g/L ;n= 2). There was a significant difference between the 7th and the 14th, 21st of 28th day statistically(P＜0.05). PC Ⅲ was not detected in control eyes. Conclusion:The PC Ⅲ level in the vitreous of rabbit eyes with experimental PVR increased significantly from the 7th to the 28th day after macrophages injection and is well consistent with the time course of scarring and the development of traction retinal detachment in the PVR model. （Chin J Ocul Fundus Dis,1996,12: 43-44）