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121.
Diverse functions of the p75 neurotrophin receptor 总被引:5,自引:0,他引:5
Yamashita T Fujitani M Hata K Mimura F Yamagishi S 《Anatomical science international / Japanese Association of Anatomists》2005,80(1):37-41
The pan-neurotrophin receptor p75NTR belongs to a large family of receptors, which includes tumor necrosis factor receptors, Fas and approximately 25 other members. The p75NTR is the first receptor to be cloned molecularly. Recent years have seen the emergence of a consensus regarding the signaling pathways activated by p75NTR and its potential biological function, although receptor characterization had not been targeted for some years. We now know that p75NTR has surprisingly diverse effects, ranging from cell death to regulation of axon elongation. This diversity can be explained by the complex formation of p75NTR with other receptors and multiple signaling molecules that interact with the intracellular domain of p75NTR. 相似文献
122.
Iliac and sacral articular cartilage of 25 human sacroiliac joints (1–93 years) are examined by light microscopy and immunohistochemistry
in order to gain further insight into the nature and progress of degenerative changes appearing during aging. These changes
can already be seen in younger adults as compared to cartilage degeneration known in other diarthrodial joints. Structural
differences between sacral and iliac cartilage can already be observed in the infant: the sacral auricular facet is covered
with a hyaline articular cartilage, reaching 4 mm in thickness in the adult and staining intensely blue with alcian blue at
pH1. Iliac cartilage of the newborn is composed of a dense fibrillar network of thick collagen bundles, crossing each other
at approximately right angles. A faint staining with alcian blue suggests a low content of acidic glycosaminoglycans. In the
adult, iliac cartilage becomes hyaline and its maximal thickness reaches 1–2 mm. Both articular facets exhibit morphological
changes during aging that are more pronounced in the iliac cartilage and resemble osteoarthritic degeneration; the staining
pattern of the extracellular matrix becomes inhomogenous, chondrocytes are arranged in clusters and the articular surface
develops superficial irregularities and fissures. Sometimes fibrous tissue fills up these defects. Nevertheless, large areas
of iliac cartilage remain hyaline in nature. Sacral articular cartilage often remains largely unaltered until old age. The
sacral subchondral bone plate is usually thin and shows spongiosa trabeculae inserted at right angles, suggesting a perpendicular
load on the articular facet. Iliac subchondral spongiosa shows no definite alignment and joins the thickened subchondral bone
plate in an oblique direction. The iliac cartilage therefore seems to be stressed predominantly by shearing forces, arising
from the changing monopodal support of the pelvis during locomotion. The subchondral bone plate on both the iliac and sacral
auricular facet is penetrated by blood vessels that come into close contact with the overlying articular cartilage. These
vessels may contribute to the high incidence of rheumatoid and inflammatory diseases in the human sacroiliac joint. Immunolabelling
with an antibody against type II collagen reveals a diminished immunoreactivity in the upper half of adult sacral cartilage
and only a faint and irregular labelling in the iliac cartilage. Type I collagen can be detected in a superficial layer on
the sacral articular surface and around chondrocyte clusters in iliac cartilage, as in dedifferentiating chondrocytes during
the development of osteoarthritis.
Accepted: 22 April 1998 相似文献
123.
Batanov AN Ebert LY Dimov PG Pyshkin SA 《Bulletin of experimental biology and medicine》2000,130(8):798-801
Reparative regeneration after fetal tissue transplantation and after surgical stimulation was studied in rats with experimental
cirrhosis of the liver. Fetal tissue restored the morphology and function of cirrhotic liver and modified functional activity
of peritoneal macrophages.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 130, No. 8, pp. 216–219, August, 2000 相似文献
124.
Interleukin-1-stimulated cartilage degradation in bovine articular cartilage explants is effectively inhibited by several different dithiocarbamates with IC50's in the micromolar range.accepted by W. B. van den BergSupported by OsteoArthritis Sciences, Inc. 相似文献
125.
大鼠肝再生过程中碱性磷酸酶活性变化及其超微细胞化学研究 总被引:4,自引:0,他引:4
目的 研究2/3肝切除后大鼠肝再生过程中碱性磷酸酶(AKP)活性的变化及其细胞定位。方法 利用比色法对AKP活性进行定量分析;用酶的原位复性电泳技术分析再生肝中AKP的种类和活性变化;用电镜细胞化学方法研究酶定位。结果 在肝部分切除后的肝再生期间,AKP出现两个活性高峰(16h和19h),在每个活性高峰后,AKP均有显著下降;获得3种肝型AKP同工酶(140、160和180kD),其中180kD的AKP只在肝再生过程中出现;随着肝再生的进展,AKP活性出现在细胞的不同部位。结论 AKP在肝再生过程中起重要作用,可能参与细胞代谢、物质转运、DNA合成和细胞分化。 相似文献
126.
人工组织神经移植物修复狗缺损坐骨神经后腓肠肌的形态观察 总被引:3,自引:0,他引:3
目的 了解复合型医用可降解材料制成的人工组织神经移植物辅加神经再生素修复狗坐骨神经缺损后,腓肠肌的形态变化。方法 将人工组织神经移植物连接在狗的坐骨神经缺损30mm处。以自体神经桥接和神经缺损的狗为对照组Ⅰ和Ⅱ。术后6个月时取腓肠肌进行称重、特殊染色和组织化学染色,显微镜下了解腓肠肌的形态变化并进行图像定量分析,同时了解肌纤维的超微结构变化。结果 术后6个月,实验组腓肠肌的萎缩形态指标变化均轻于对照组Ⅱ,而与对照组Ⅰ相似。结论 经人工组织神经移植物修复缺损的坐骨神经后,使腓肠肌又重新获得神经支配,肌肉萎缩明显减轻。 相似文献
127.
M. F. Humphrey S. A. Dunlop A. Shimada L. D. Beazley 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,90(3):630-634
Summary In this study, we crushed one optic nerve in the frog Litoria (Hyla) moorei and at intervals thereafter anterogradely labelled optic axons with horseradish peroxidase (HRP). For one series, HRP was applied between the eye and the crush site and in a second series between the crush site and the chiasm. A tectal projection of regenerating axons was seen in both series but, in addition, up to 12 weeks post-crush, the second series displayed an additional projection. Its appearance matched that of the disconnected, but persisting, optic axon terminals which are found after enucleation or optic nerve ligation. We conclude that, in the frog, many disconnected optic axons persist throughout the period of optic nerve regeneration and of restoration of an orderly retino-tectal map.Abbreviation HRP
horseradish peroxidase 相似文献
128.
Kornilova ZK Selishcheva AA Perel'man MI 《Bulletin of experimental biology and medicine》2001,131(2):191-194
Phosphatidylcholine liposomes in a dose of 25 mg/kg displayed wound-healing properties. They increased the count of alveolar macrophages, lymphocytes, and microvessels in damaged regions and, therefore, attenuated emphysematous changes in the lungs. 相似文献
129.
目的:研究在隔膜条件下引导性骨再生过程中成骨细胞的来源,进一步认识引导性骨再生的机制.方法:以成年新西兰兔为研究对象,在双侧挠骨中段制作标准骨缺损不愈合模型,用硅胶膜成管状包裹一侧骨缺损,另一侧无特殊处理为对照.术后分别进行X线检查、常规HE染色以及SP方法BMP、BGP抗体的免疫组化染色.结果:硅胶膜在骨缺损处形成隔离密闭的腔室,将周围组织阻挡于骨缺损之外.早期骨端骨内膜、骨髓基质细胞大量增殖,形成肉芽组织占据骨缺损.骨再生过程中表现出明显的组织学特征:骨痂表面为2~3层成骨细胞,骨缺损中央为肉芽组织,两者之间为数层细胞形成的移行区,细胞排列疏松.早期骨端骨内膜、骨髓基质细胞BMP、BGP呈强阳性染色,骨痂生长过程中,移行区部分细胞呈阳性染色.结论:结果表明在隔膜条件下骨再生的成骨细胞在早期来源于髓内的骨内膜和骨髓基质细胞,骨痂形成后,成骨细胞则来源于骨内膜、骨髓、骨膜增殖细胞共同形成的肉芽组织中的间质细胞或成纤维细胞. 相似文献
130.
The expression of insulin-like growth factor I (IGF-I, somatomedin C) was studied in regenerating skeletal muscle. Irreversible damage to skeletal muscle cells was induced in the extensor digitorum longus muscle (EDL) of adult rats by ischaemia, preceded by glycogen depletion, and the regeneration process was studied for periods up to 14 days after injury. The IGF-I was demonstrated by indirect immunofluorescence. Immunoreactivity against ribonucleotide reductase (RR) was used as a marker for DNA synthesis, that is, cell proliferation. Increased IGF-I immunoreactivity could be demonstrated within 24h after injury in satellite cells, intramuscular nerves and in blood vessels. The IGF-I immunoreactivity remained virtually unchanged in the contralateral, undamaged EDL. An increasing number of satellite cells, expressing high IGF-I immunoreactivity, could be demonstrated in the injured EDL, and within 72 h myoblasts, expressing high IGF-I and RR immunoreactivity, were formed. Small immature muscle cells, displaying high IGF-I immunoreactivity, were observed 4 days after injury. Increased IGF-I immunoreactivity was still obvious in the regenerated muscle cells 14 days after injury while RR immunoreactivity was seen only in scattered satellite cells. It is concluded that IGF-I may act as a trophic factor during regeneration of skeletal muscle after injury. 相似文献