Search results for "CARTILAGE"
showing 10 items of 252 documents
Distribution of Cartilage Proteoglycan (Aggrecan) Core Protein and Link Protein Gene Expression during Human Skeletal Development
1991
The distribution of cartilage proteoglycan core protein (aggrecan) and cartilage proteoglycan link protein was investigated by in situ hybridization during different stages of human skeletal development. Aggrecan and link protein expression were confined to chondrocytes of the developing skeleton and other cartilaginous structures. Distribution and intensity of the signal was identical with aggrecan as compared to link protein probes. Parallel to the calcification of cartilaginous matrix, chondrocytes of this area lost the expression of aggrecan and link protein specific mRNA and stayed negative throughout the following stages of skeletal development. Highest expression was found in the low…
Collecting evidence for a stem cell hypothesis in HCC.
2010
Ever since Ernest McCulloch and James E Till defined essential stem cell properties, the field of stem cell biology has attracted increasing interest.1 Manipulating embryonic stem cells has resulted in advanced genetic technologies such as knock-out and transgenic animals, providing valuable models to study genetic influence on a wide variety of diseases.2 The success in manipulating stem cells and the ability to differentiate them into diverse tissues brought with them countless concepts of utilising stem cells in medicine. The idea of perpetually dividing pluripotent cells, capable of differentiating into nearly every possible cell or tissue type, seems like an inexhaustible resource for …
Deguna vārstules aktivitātes novērtējums, izmantojot 4 fāžu rinamometru. Jauna parametra ieviešana un statistiskais novērtējums
2017
Darba mērķis: jauna parametra (deguna vārstules indeksa) izpēte, identificējot cilpas rinomanometriskajās līknēs kā deguna vārstules aktivitāties pazīmi. Skaitliski novērtēt rinomanometrijas cilpu nozīmi ar deguna vārstules indeksa palīdzību. Materiāli un metodes: rinomanometrijas dati tika iegūti no 250 pacientiem (veicot aktīvas priekšējās rinomanometrijas mērījumus), ar rinomanometru 4RHINO (RhinolabGermany), programmatūras versijā 4.31 un 5.01. Mērījumi tika veikti pirms dekongestantu lietošanas un pēc dekongestantu lietošanas, atkārtojot mērījumus pēc 10 minūtēm. Deguna vārstules indekss tika atlasīts un pievienots "HRR-Export-file". Statistiskajai analīzei tika izmantots Microsoft Off…
In vitro 30 nm silver nanoparticles promote chondrogenesis of human mesenchymal stem cells
2015
Silver nanoparticles (Ag NPs) are one of the most widely used products in nano-medicine due to their broad-spectrum antimicrobial activity. In tissue engineering, Ag NPs are often incorporated as antibacterial agents in scaffolds, which are subsequently loaded with human bone marrow-derived mesenchymal stem cells (hMSCs). In this study, we investigated the effect of Ag NPs on chondrogenesis of hMSCs. The synthesized Ag NPs were spherical in shape, with a mean diameter of ∼30 nm. After 24 h exposure, Ag NPs were taken up into hMSCs and mainly distributed in the cytoplasm, the nucleus and different sized vesicles. We examined the chondrogenesis through several methods, including glycosaminogl…
Computed tomography detects changes in contrast agent diffusion after collagen cross-linking typical to natural aging of articular cartilage
2011
SummaryObjectiveThe effect of threose-induced collagen cross-linking on the mechanical and diffusive properties of cartilage was investigated in vitro. In particular, we investigated the potential of Contrast Enhanced Computed Tomography (CECT) to detect changes in articular cartilage after increased collagen cross-linking, which is an age-related phenomenon.MethodsOsteochondral plugs (Ø=6.0mm, n=28) were prepared from intact bovine patellae (n=7). Two of the four adjacent samples, prepared from each patella, were treated with threose to increase the collagen cross-linking, while the other two specimen served as paired controls. One sample pair was mechanically tested and then mechanically …
Volumetric changes of articular cartilage during stress relaxation in unconfined compression
2000
The time-dependent lateral expansion and load relaxation of cartilage cylinders subjected to unconfined compression were simultaneously recorded. These measurements were used to (1) test the assumption of incompressibility for articular cartilage, (2) measure the Poisson's ratio of articular cartilage in compression and (3) investigate the relationship between stress relaxation and volumetric change. Mechanical tests were performed on fetal, calf, and adult humeral head articular cartilage. The instantaneous Poisson's ratio of adult cartilage was 0.49+/-0.08 (mean+S.D.), thus confirming the assumption of incompressibility for this tissue. The instantaneous Poisson's ratio was significantly …
Efficacy of progressive aquatic resistance training for tibiofemoral cartilage in postmenopausal women with mild knee osteoarthritis : a randomised c…
2016
Objective: To study the efficacy of aquatic resistance training on biochemical composition of tibiofemoral cartilage in postmenopausal women with mild knee osteoarthritis (OA). Design: Eighty seven volunteer postmenopausal women, aged 60-68 years, with mild knee OA (Kellgren-Lawrence grades I/II and knee pain) were recruited and randomly assigned to an intervention (n = 43) and control (n = 44) group. The intervention group participated in 48 supervised aquatic resistance training sessions over 16 weeks while the control group maintained usual level of physical activity. The biochemical composition of the medial and lateral tibiofemoral cartilage was estimated using single-slice transverse …
Complexity of IL-1β induced gene expression pattern in human articular chondrocytes
1997
The mRNA fingerprinting technique, differential display reverse transcription polymerase chain (DDRT-PCR), was used to detect changes in the overall pattern of gene expression in human articular knee chondrocytes-induced by interleukin-1 beta (IL-1 beta), the prototypical inducer of catabolic responses in degenerate joint diseases. One hundred different primer combinations generated approximately 10,000 different PCR fragments for IL-1 beta treated, as well as for untreated human chondrocytes, cultivated in alginate beads. This represented 53% of all expressed chondrocyte genes as based on statistical considerations. Side by side comparisons of differential display patterns originating from…
Expression patterns of complex glycoconjugates and endogenous lectins during fetal development of the viscerocranium
1999
Summary Experimental evidence suggests that carbohydrates and their corresponding receptors (endogenous lectins) decode biological information. Therefore, the expression of complex oligosaccharides — the potential ligand part of this recognition system — during chondrogenesis and osteogenesis was determined in the viscerocranium of fetal rats by mapping the staining patterns of exogenous lectins. Results were compared with the expression of bone- and/or cartilage-specific core proteins and the binding profiles of neoglycoconjugates. These synthetic tools make possible the localization of sugar-ligand-binding sites. The spatial and temporal distribution patterns of glycoconjugates were highl…
Biostable Scaffolds of Polyacrylate Polymers Implanted in the Articular Cartilage Induce Hyaline-Like Cartilage Regeneration in Rabbits
2017
[EN] Purpose: To study the influence of scaffold properties on the organization of ¿in vivo¿ cartilage regeneration. Our hypothesis is that stress transmission to the cells seeded inside the scaffold pores or surrounding it, which is highly dependent on the scaffold properties, determine differentiation of both mesenchymal cells and dedifferentiated autologous chondrocytes. Methods: Four series of porous scaffolds made of different polyacrylate polymers, previously seeded with cultured rabbit chondrocytes or without cells preseeded, were implanted in cartilage defects in rabbits. Subchondral bone was always injured during the surgery in order to allow blood to reach the implantation site an…