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1.
目的探讨补骨脂素抗增生性瘢痕的作用机制。方法体外培养成纤维细胞,按随机数字表法分为正常组(培养正常成纤维细胞)、瘢痕组(培养增生性瘢痕成纤维细胞)、TGF-β1组(10 ng/ml TGF-β1处理增生性瘢痕成纤维细胞5 min^12 h)、Smurf2 RNA干扰组[Smad泛素化调节因子2(Smad ubiquitin regulatory factor2,Smurf2)siRNA转染增生性瘢痕成纤维细胞72 h]、补骨脂素组(10μmol/L补骨脂素处理增生性瘢痕成纤维细胞继续培养72 h)、补骨脂素+TGF-β1组(增生性瘢痕成纤维细胞加入补骨脂素培养72 h后加入TGF-β1培养6 h)。采用Western blot法检测Smurf2、α-平滑肌肌动蛋白(α-actin SMA,α-SMA)蛋白表达;RT-PCR法检测Ⅰ型胶原蛋白mRNA表达;ELISA法检测TGF-β1蛋白分泌。结果与正常组比较,瘢痕组Smurf2蛋白[(0.83±0.08)比(0.38±0.07)]表达增加(P<0.05);与瘢痕组比较,Smurf2 RNA干扰组TGF-β1[(2.2±0.18)比(4.2±0.47)]表达降低(P<0.05);TGF-β1组Smurf2[(0.71±0.06)比(0.42±0.04)]、α-SMA[(1.42±0.12)比(0.91±0.09)]蛋白表达增加(P<0.05),Ⅰ型胶原蛋白mRNA[(0.72±0.09)比(0.41±0.07)]表达增加(P<0.05);补骨脂素组Smurf2[(0.05±0.01)比(0.42±0.04)]、α-SMA[(0.71±0.07)比(0.91±0.09)]蛋白表达降低(P<0.05),Ⅰ型胶原蛋白mRNA表达[(0.12±0.04)比(0.41±0.07)]降低(P<0.05)。结论补骨脂素可能通过TGF-β1/Smurf2信号通路抑制α-SMA蛋白表达,从而降低Ⅰ型胶原蛋白表达,起到抑制瘢痕形成的作用。 相似文献
2.
3.
For the past 10 years the alfa-hydroxyacids and the bovine collagen injection have been used for peeling and the correction of multiple skin diseases. Until now, such progressive achievement has occurred in separate parallels just like the indications that have been held distinct. However, the studies carried out in order to clarify the mechanical action of the two substances have shown a common and fundamental denominator: the stimulation of synthesis of the new collagen in the patient's skin. On the basis of these results and the existence of common clinical indications of the use of glycolic acid and collagen, the authors have worked out a protocol involving a combined and contemporary application in progressive steps. They developed the rationales of such protocol and analyzed the results of its application on a number of carefully selected patients for a clinical comparison and on a sample of rats for a histological comparison. They have concluded that the contemporary use of glycolic acid and bovine collagen is a simple and safe method whose synergy action leads to more intense and long-lasting effects than the ones observed in the isolated application of the two substances. The authors have also obtained interesting and significant histological results. 相似文献
4.
Morphologic characterization of osteoblast-like cell cultures isolated from newborn rat calvaria 总被引:4,自引:0,他引:4
Dominique Masquelier Béatrice Herbert Nadine Hauser Pascal Mermillod Edgard Schonne Claude Remacle Ph.D. 《Calcified tissue international》1990,47(2):92-104
Summary Two methods for harvesting osteoblast-like cell populations from newborn (10 days) rat calvaria were compared. The first one
consisted in culturing the periosteum-free bones and then trypsinizing the cells on the bone surface. The second one involved
the migration of the osteoblasts on glass fragments before trypsinization. Since the plating efficiency, the proportion of
alkaline phosphatase-positive cells, the population doubling time, and the calcium deposition were more adequate, the second
method was used to further characterize the behavior of the cultures. During the first week of culture, the cells featured
shapes similar to those observedin vivo on the surface of periosteum-free calvaria. They formed multilayers and, in the presence of ascorbic acid, synthetized an
organic matrix containing exclusively type I collagen. Later, small amounts of type III collagen appeared. The cells were
embedded in the matrix and progressively acquired the morphologic phenotype of osteocyte-like cells. The matrix mineralized
in the presence of β-glycerophosphate. The technique of dropinoculation (high concentration of cells in a small volume of
medium) promoted the multilayer formation and the achievement of large mineralized plates (about 1 cm2) in 3 weeks of culture. 相似文献
5.
The effects of 10% dietary xylitol supplementation in ovariectomized rats were studied on the degradation of bone organic
and inorganic structures. The osseal concentrations of hydroxyproline, pyridinoline, and deoxypyridinoline were analyzed by
high-performance liquid chromatography. Bone resorption was measured in [3H]tetracycline-prelabeled rats by urinary excretion of 3H, and by the amount of 3H preserved in bone. Bone trabeculation was measured by a computer image analyzer from sections stained by the method of von
Kossa. The amount of collagen in bone organic fraction was lower in ovariectomized rats as compared with the sham-operated
controls. This most likely is partly a consequence of an increased resorption, and partly a consequence of a higher proportion
of immature periosteal bone in the ovariectomized animals, leading to a higher ratio of noncollagenous protein to collagen.
The number of pyridinium crosslinks was lower in proportion, indicating no selective changes in the structure of collagen.
Dietary xylitol significantly retarded the ovariectomy-associated decrease in the relative amount of collagen and the number
of its mature crosslinks. Ovariectomy doubled the excretion of 3H and caused a significant decrease in the amount of 3H preserved in bone; both these changes were significantly retarded by the 10% dietary xylitol supplementation. Ovariectomy
significantly decreased the volume of bone trabeculae, but this effect was also significantly inhibited by the xylitol supplementation
in the diet. In conclusion, these findings suggest a dietary xylitol-induced normalizing effect on the rate of bone turnover
in ovariectomized rats.
Received: 12 February 1996 / Accepted: 20 August 1996 相似文献
6.
For centuries snake venoms have been known to interfere with haemostasis and this is now known basically due either to toxins activating/inhibiting clotting factors, having effects on blood vessels or interfering with platelet function. In this short review, the interaction of one major group of toxins, the snake venom metalloproteinases, with platelets is considered. This is relevant for understanding the mechanism of haemorrhage induced by these toxins. 相似文献
7.
超声引导胶原酶治疗外侧型腰椎间盘突出症 总被引:3,自引:1,他引:2
目的探讨超声引导胶原酶治疗外侧型腰椎间盘突出症的疗效及安全性.方法在相应椎间盘突出的棘突间,旁开1.5~2.5cm处经皮穿刺,采用超声引导定位,穿刺成功后,先进行加压试验,再进行麻醉试验,无腰麻征象后,将胶原酶注入到突出的椎间盘内或周围.结果 231例病人出院时的优良率为92.21%,有效率为99.57%;随访1~5年的优良率为92.65%,有效率为99.58%.近期与远期疗效比较无显著性差异(χ2=0.129,P>0.05).结论利用超声引导监测、定位,注射胶原酶治疗外侧型腰椎间盘突出症,安全性强、有效率高. 相似文献
8.
M. M. Giraud-Guille 《Calcified tissue international》1988,42(3):167-180
Summary Ultrathin sections of decalcified human compact bone, observed by transmission electron microscopy, reveal that collagen fibrils
can be distributed in the form of a superimposed series of nested arcs. This characteristic pattern has never been interpreted
in previous works on compact bone structure. We demonstrate, by goniometric observations at the ultrastructural level, that
such series of nested arcs are a consequence of the “twisted plywood” architecture of collagen fibrils in the compact bone
matrix. In the same specimens, an “orthogonal plywood” disposition of collagen fibrils is also observed; a transition exists
between these two types of orders. We show that the “twisted plywood structure” accounts well for certain optical properties
of osteons, observed in polarizing microscopy, described as “intermediate osteons.” The particular geometry of collagen fibrils,
leading to nested arcs in oblique sections, is analogous to the distribution of molecules in certain liquid crystals (called
cholesteric liquid crystals). The principle of a liquid crystalline self-assembly of the collagen matrix in bone is therefore
discussed. 相似文献
9.
High Cell-Density Culture System of Hepatocytes Entrapped in a Three-Dimensional Hollow Fiber Module with Collagen Gel 总被引:2,自引:0,他引:2
Kazuyoshi Takeshita Haruaki Ishibashi Masayuki Suzuki Takumi Yamamoto Toshihiro Akaike Masashi Kodama 《Artificial organs》1995,19(2):191-193
Abstract: A compact three-dimensional (3D) module is needed for hepatocyte culture in order to develop an effective hybrid artificial liver system that can retain hepa-tocellular structure and differentiated functions. We treated the 3D module with collagen gel to entrap rat hepatocytes. This method yielded a high hepatocellular density (2 times 107 cells/ml) over a period of 14 days and maintained the secretion of albumin and ureogenesis at the same level as the control monolayer method. The ammonia removal remained at 43% of the Day 0 value over 8 days of perfusion. Our data show that this approach may be useful for liver support therapy in an ex-tracorporeal circuit. 相似文献
10.
Hirotsugu Kojima Syunji Sasaki Tetsuya Tamaki Hiroshi Kameda Satoru Yamasaki Michio Kimura 《Medical Electron Microscopy》1994,27(2):149-158
An ultrastructural study was undertaken concerning morphological changes within the autografted patellar tendon (PT) after
being transplanted to the anterior cruciate ligament (ACL) in mongrel dogs. After 4 weeks, the arrangements of both large
and small collagen fibrils in the PT graft became disordered, and the number of inflammatory cells increased. However, the
same PT grafts revealed postsurgical signs of newly-produced collagen fibrils around activated fibroblasts at 12 to 24 weeks.
At 52 weeks after the transplantation, small collagen fibrils increased in both number and density, showing a remarkable morphological
similarity to the collagen fibrils of normal ACL. These data indicate that the characteristics of the PT graft eventually
resemble those of a normal ACL.
This paper was presented in part at the Combined Meeting of the Orthopedic Research Societies of the USA, Japan and Canada
in Banff, Alberta, Canada, October, 1991. 相似文献