* Hyaluronic acid secretion by synoviocytes alters under cyclic compressive load in contracted collagen gels.
- Knee osteoarthritis is a degenerative disease of diarthrodial joints. Biomechanical factors are considered as risk factors for the disease, the knee joint being normally subject to pressure. Some studies have examined the biomechanical environment of the knee joint in vitro. The aim of this study was to establish a culture model to mimic the knee joint environment. As a first step, synoviocytes induced contraction of three-dimensional collagen gels. Next, contracted collagen gels containing synoviocytes underwent cyclical compression ranging from 0 to 40 kPa at a frequency of 1.0 Hz for 1.5, 3, 6 and 12 h using the FX-4000C™ Flexercell(®) Compression Plus™ System. RNA in collagen gels was extracted immediately after compression and mRNA expression levels of HAS genes were analyzed by quantitative RT-PCR. Culture medium was collected 48 h after compression and analyzed by agarose gel electrophoresis and cellulose acetate electrophoresis. Synoviocytes in contracted collagen gels were stimulated by cyclic compressive load. Long-term compressive stimulation led to the production of higher molecular weight hyaluronic acid, whereas, short-term, compressive stimulation increased the total amount of hyaluronic acid. Furthermore, mRNA expression levels of both HAS-1 and HAS-2 were significantly higher than without compression. Taken together, using this gel culture system, synoviocytes synthesized higher molecular weight hyaluronic acid and produced large quantities of hyaluronic acid through up-regulation of HAS gene expression. Therefore, the contracted collagen gel model will be a useful in vitro three-dimensional model of the knee joint.
=>表現すること, 式, 表現, 表示, 言い回し, 表現法, 表情
Overview of noun expression
The noun expression has 9 senses (first 6 from tagged texts)
1. (23) expression, look, aspect, facial expression, face -- (the feelings expressed on a person's
face; "a sad expression"; "a look of triumph"; "an angry face")
2. (18) expression, manifestation, reflection, reflexion -- (expression without words; "tears are an
expression of grief"; "the pulse is a reflection of the heart's condition")
3. (15) expression, verbal expression, verbalism -- (the communication (in speech or writing) of
your beliefs or opinions; "expressions of good will"; "he helped me find verbal expression for my
ideas"; "the idea was immediate but the verbalism took hours")
4. (5) saying, expression, locution -- (a word or phrase that particular people use in particular
situations; "pardon the expression")
5. (4) formulation, expression -- (the style of expressing yourself; "he suggested a better
formulation"; "his manner of expression showed how much he cared")
6. (4) formula, expression -- (a group of symbols that make a mathematical statement)
7. expression -- ((genetics) the process of expressing a gene)
8. construction, grammatical construction, expression -- (a group of words that form a constituent
of a sentence and are considered as a single unit; "I concluded from his awkward constructions that
he was a foreigner")
9. expression -- (the act of forcing something out by squeezing or pressing; "the expression of milk
from her breast")
--- WordNet end ---