[Current therapy status and research progress of cartilage defects of knees].

To demonstrate the current strategies for treating cartilage defects of knees and the related research. Published papers about cartilage defects were searched and reviewed. The current strategies for the treatment were summarized.

Preparation and characterization of bone marrow mesenchymal stem cell-derived extracellular matrix scaffolds.

The aim of this study was to assess the feasibility of creating extracellular matrix (ECM) scaffolds from mesenchymal stem cells. Bone marrow mesenchymal stem cell (BMSC)-derived ECM (BMSC-dECM) scaffolds were fabricated by lyophilization after crosslinking, without using a decellularization process. Acellular porcine chondrocyte-derived ECM (AC-dECM) scaffolds were used as a control.

The maturity of tissue-engineered cartilage in vitro affects the repairability for osteochondral defect.

Cartilage tissue engineering using cells and biocompatible scaffolds has emerged as a promising approach to repair of cartilage damage. To date, however, no engineered cartilage has proven to be equivalent to native cartilage in terms of biochemical and compression properties, as well as histological features. An alternative strategy for cartilage engineering is to focus on the in vivo regeneration potential of immature engineered cartilage.

Evaluation of transtibial double-bundle posterior cruciate ligament reconstruction using a single-sling method with a tibialis anterior allograft.

Background: The authors devised a double-bundle posterior cruciate ligament reconstruction technique in combination with a single-sling method. However, the double-bundle technique needs more simplicity and a decreased possibility of failure.

Hypothesis: A novel surgical technique of transtibial double-bundle posterior cruciate ligament reconstruction using a single-sling method with a tibialis anterior allograft, previously introduced, produces satisfactory results.

Cartilage engineering using cell-derived extracellular matrix scaffold in vitro.

A cell-derived extracellular matrix (ECM) scaffold was constructed using cultured porcine chondrocytes via a freeze-drying method, and its ability to promote cartilage formation was evaluated in vitro. Scanning electron microscope (SEM) revealed that the scaffold had highly uniform porous microstructure. Then, rabbit chondrocytes were seeded dynamically on ECM scaffold and cultured for 2 days, 1, 2, and 4 weeks in vitro for analysis.

Design of antiangiogenic hypoxic cell radiosensitizers: 2-nitroimidazoles containing a 2-aminomethylene-4-cyclopentene-1,3-dione moiety.

We designed chiral 2-nitroimidazole derivatives containing a 2-aminomethylene-4-cyclopentene-1,3-dione moiety as antiangiogenic hypoxic cell radiosensitizers. Based on results of molecular orbital calculations, the 2-aminomethylene-4-cyclopentene-1,3-dione moiety is expected to show high electrophilicity comparable to that of the 2-methylene-4-cyclopentene-1,3-dione moiety included in TX-1123 and tyrphostin AG17. We evaluated the antiangiogenic and radiosensitizing effects of the new compounds, along with other biological properties including their activities as hypoxic cytotoxicities and protein tyrosine kinase (PTK) inhibitory activities.

Posterior cruciate ligament reconstruction with a single-sling technique using a tibialis anterior tendon allograft.

Reconstruction of the posterior cruciate ligament (PCL) has been performed in various ways. Recent biomechanical tests revealed that a double-bundle graft with a 2-tunnel technique is more likely to restore normal knee stability throughout the full range of knee motion. Several techniques using double-bundle grafts have been implemented for PCL reconstruction; however, each technique has its own advantages and disadvantages.

In vivo cartilage tissue engineering using a cell-derived extracellular matrix scaffold.

We have observed in our previous study that a cell-derived extracellular matrix (ECM) scaffold could assure the growth of a cartilage tissue construct in vitro. The purpose of the present study was to evaluate the feasibility of a chondrocyte-seeded cell-derived ECM scaffold by implanting it in vivo in nude mouse. A porous cell-derived ECM scaffold was prepared with a freeze-drying protocol using porcine chondrocytes.

Human amniotic membrane as a delivery matrix for articular cartilage repair.

The purpose of this study is to evaluate the feasibility of human amniotic membrane (HAM) as a chondrocyte carrier by assessing cell proliferation and maintenance of phenotype in vitro and cartilage regeneration in vivo. Intact HAM was treated with 0.1% trypsin-ethylenediaminetetraacetic acid (EDTA) for 15 min and the epithelial cells removed to make a denuded HAM.

Surgical treatment for distal clavicle fracture associated with coracoclavicular ligament rupture using a cannulated screw fixation technique.

Background: A clavicle fracture is a common traumatic injury. However, the high percentage of distal clavicle fractures associated with a rupture of the coracoclavicular (CC) ligament can result in delayed union or nonunion. There is no standard treatment for a clavicle fracture.

The effect of sonication on simulated osteoarthritis. Part I: effects of 1 MHz ultrasound on uptake of hyaluronan into the rabbit synovium.

High molecular weight (MW) hyaluronan (HA) preparation is considered to be more biologically active than HAs of lower MWs. However, many of the HA preparations currently used to treat osteoarthritis (OA) have lower MWs by the enhanced penetration of HA molecules into the synovial lining cells. In this study, we determined the effectiveness of sonophoresis on the delivery of high MW HA into synovial membrane using an animal model of OA.

Angiogenesis inhibitor TX-1898: syntheses of the enantiomers of sterically diverse haloacetylcarbamoyl-2-nitroimidazole hypoxic cell radiosensitizers.

(R)- and (S)-Epichlorohydrins were used to prepare the enantiomers of sterically diverse haloacetylcarbamoyl-2-nitroimidazoles that function as hypoxic cell radiosensitizers. The synthetic design allowed for introduction of a side chain of varying bulk that permitted an examination of the steric effects on enantio-discrimination in biological assay systems. The single stereocenter also connected the two pharmacophores--a 2-nitroimidazole moiety critical to hypoxic cell radiosensitization, and a haloacetylcarbamoyl group to function as an anti-angiogenesis pharmacophore.