ISSN:0736-0266    

DOI:10.1002/jor.1100140402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractIn this study, we successfully transferred theEscherichia coliβ‐galactosidase gene, LacZ, into the chicken tendon and tendon sheath by a recombinant adenovirus. The recombinant adenovirus Adv‐βgal that carried theE. coliLacZ gene was constructed by homologous recombination in 293 cells (human transformed embryonic kidney) between the expressing vector and the ClaI large fragment of adenovirus 5 genome. Each chicken received a 10 μl injection, containing 105plaque‐forming units of recombinant virus Adv‐βgal, into the tendon sheath of the long toe. Samples of tendon and tendon sheath were harvested at 3, 30, and 75 days after the injection. The LacZ gene transfer was detected for its coding product β‐galactosidase by staining with X‐gal solution. The results showed that all tendon and tendon sheath samples from the three harvest times stained positive (blue). The tendon sheath samples were more extensively stained; staining of the tendon was limited to the epitenon layer. These data suggest that a functional exogenous gene can potentially be transferred into the tendon and tendon sheath by similar techniques; such techniques may be used to improve healing and reduce ad

ISSN:0736-0266    

DOI:10.1002/jor.1100140403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractRotator cuff and biceps tendons that appeared grossly normal were procured from adult cadavers without a history of shoulder problems. These tendons were analyzed for the amount and type of glycosaminoglycan, type of proteoglycan, and histology. When compared with the distal/tensional region of biceps tendon, the glycosaminoglycan content of supraspinatus, infraspinatus, and subscapularis tendons was 2.5‐fold higher and the glycosaminoglycan content of the proximal/compressed region of biceps tendon was 3‐fold higher. The ratio of hyaluronic acid to chondroitin sulfate/dermatan sulfate in all three cuff tendons was approximately 1. Rotator cuff tendons contained large proteoglycan similar to aggrecan, as demonstrated by sodium dodecyl sulfate‐polyacrylamide gel migration, elution from Sepharose CL‐4B, and content of both chondroitin sulfate and keratan sulfate chains. Both decorin and biglycan were also present, as demonstrated by migration in sodium dodecyl sulfate‐polyacrylamide gels and core protein immunoreactivity. In contrast, decorin was the only proteoglycan prominent in distal/tensional regions of biceps tendon. Histological analysis showed layers of loosely organized, alcian blue‐stained material running between the longitudinal collagen fiber bundles. The proteoglycan content of rotator cuff tendons was similar to fibrocartilage in tendons that have been subjected to compressive loadsin situ. This suggests that cells of normal adult rotator cuff tendons have adapted to loads distinct from pure tension. However, the histological organization did not resemble mature fibrocartilage. The increased amount of proteoglycan in rotator cuff tendons may serve to separate and lubricate collagen bundles as they move relative to each other during normal shou

ISSN:0736-0266    

DOI:10.1002/jor.1100140404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractTo identify estrogen and progesterone target cells in the human anterior cruciate ligament, immunohistochemical localization of both estrogen and progesterone receptors was performed in 17 specimens of human anterior cruciate ligament. All ligament specimens were obtained at surgery. Thirteen specimens were from women, and four were from men: the average age was 57 years (range, 18–78 years). Eleven specimens (from nine women and two men) came from total knee replacements for osteoarthritis of the knee; three (from two women and one man). from reconstructions of the anterior cruciate ligament; two (both from women). from medial meniscectomies: and one (from a man), from an amputation secondary to chondrosarcoma of the pelvis. An immunoperoxidase method using monoclonal antibodies to the estrogen and progesterone receptors was employed to identify estrogen and progesterone target cells in the anterior cruciate ligament. Staining of both receptors was demonstrable in 14 specimens, and in the remaining three specimens less than 15% of the cells were stained. Both estrogen and progesterone receptors were localized to synoviocytes in the synovial lining, fibroblasts in the anterior cruciate ligament stroma, and cells in the blood vessel walls of the ligament. This demonstration of receptors for estrogen and progesterone in the cells of anterior cruciate ligament suggests that female sex hormones may have an effect on its structure and compositio

ISSN:0736-0266    

DOI:10.1002/jor.1100140405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractWe studied the healing response of a devitalized anterior cruciate ligament to a treatment of initial anterior‐posterior joint translation in goats. Devitalization and devascularization were achieved by five successive freeze‐thaw cycles. Anterior‐posterior translation was surgically altered by an osteotomy of the tibial attachment of the devitalized ligament and its reattachment either in the anatomical position or in a position 5 mm posterior. Six weeks after the first surgery, the same procedure was performed on the contralateral limb, except that the ligament was reattached in the alternate position. Six months after the initial surgery, femur‐anterior cruciate ligament‐tibia specimens were tested to determine their structural and mechanical material properties. Anatomic ligament placement resulted in reduced anterior‐posterior translation (p<0.05) and greater anterior joint stiffness (p<0.05). Maximum load (p<0.05) and ligament stiffness (p<0.01) also were greater for the anatomically placed anterior cruciate ligaments. The maximum load for anatomically placed ligaments averaged 1.625 ± 211 N (SEM). The strength of the posteriorly placed anterior cruciate ligament, 895 ± 164 N. was similar to results of historical anterior cruciate autograft reconstructions. Ligament failure occurred near the tibial insertion in the posteriorly placed ligaments more often than in the anatomically placed ligaments (four of five times compared with one of five times). Ligament failure near the tibial insertion occurred with lower mean maximum load than failure at the midsubstance or by bone avulsion (796 compared with 1.592 N: p<0.05). These data support the hypothesis that ligament laxity is important to the healing and remodeling of anterior cruciate li

ISSN:0736-0266    

DOI:10.1002/jor.1100140406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractThe healing responses of the anterior cruciate ligament and the patellar tendon differ markedly. The anterior cruciate ligament fails to heal, whereas the patellar tendon heals slowly. The basis of these differences is unknown. Since cellular proliferation is a critical element of healing, we investigated the response to explants of anterior cruciate ligament and patellar tendon from sheep knees to platelet‐derived growth factor‐AB and transforming growth factor β1 as a function of time and dose. Explants cultured for 48, 72, and 96 hours with transforming growth factor β1 (0‐100 ng/ml) or platelet‐derived growth factor‐AB (0‐200 ng/ml) were radiolabeled for the final 24 hours with [3H]thymidine, and DNA synthesis was quantified as trichloroacetic acid‐precipitable radioactivity normalized to dry tissue weight. Statistical analyses (analysis of variance) showed that transforming growth factor β1 induced a significant proliferative response in the anterior cruciate ligament at 96 hours with equivalent responses at 10.50, and 100 ng/ml, whereas the patellar tendon only responded to one condition, 10 ng/ml at 96 hours. Conversely, the patellar tendon had a significant dose‐dependent response to platelet‐derived growth factor‐AB at 72 and 96 hours, whereas the anterior cruciate ligament showed no proliferative response to platelet‐derived growth factor‐AB. The minimal response of anterior cruciate ligament to platelet‐derived growth factor‐AB could explain, at least in part, the poor repair capacity of this tissue. The response of the anterior cruciate ligament to transforming growth factor β suggests that exogenous transforming growth factor β may promote initial healing. Although growth factors have the potential to modulate soft‐tissue repair, tissue responses in tendons and ligaments ma

ISSN:0736-0266    

DOI:10.1002/jor.1100140407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractThe short‐term and long‐term effects on the growth zone in articular cartilage of transforming growth factor‐β1 and platelet‐derived growth factor‐BB injected intraarticularly into the knee joint of growing rats were investigated. The changes induced by five injections of 0.5 μg of transforming growth factor‐β1 included a rapid decrease in the size and number of hypertrophic cells and an enhanced subchondral bone formation. The changes were most marked in the patella but were also apparent in the tibia and femur. The proliferating cells became swollen and lost their normal organization. From the seventh day of the experiment to about 3 weeks, the matrix stained intensely with safranin O for proteoglycans. The alterations induced by transforming growth factor‐β also included synovial fibroplasia and synovitis, consisting predominantly of mononuclear cells. Localised necroses in the cartilage sometimes appeared after 21 days. In long‐term studies, destroyed cartilage was found in three of six rats and partial ossification of the joint cartilage was found in two after 90 and 180 days. Ossicles developed in the tendons in all six patellae. Injection of platelet‐derived growth factor‐BB resulted in an early and transitory minor increase in the osteogenic activity in the zone between cartilage and red bone marrow and later produced an ossicle in one of four tendons. None of the other changes noted after injection of transforming gro

ISSN:0736-0266    

DOI:10.1002/jor.1100140408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractThis study showed that magnetic resonance imaging can be used to visualize partial thickness cartilage lesions, 0.7 × 10 mm in area and 0.5 mm in depth, surgically induced in the femur (femoropatellar compartment) of a mini‐pig knee joint. Formalin‐fixed joints, intact as well as disarticulated, were studied by high resolution imaging using a 2.35 T, 31 cm horizontal‐bore superconducting magnet. The two‐dimensional and three‐dimensional spatial resolutions achievable were as follows: 0.12 × 0.23 mm (two‐dimensional) and 0.35 × 0.35 × 0.35 mm (three‐dimensional) for the intact joint, and 0.08 × 0.08 mm (two‐dimensional) and 0.14 × 0.14 × 0.27 mm (three‐dimensional) for the disarticulated joint. These results demonstrate that magnetic resonance imaging, together with edge detection and volume rendering, can be used to visualize

ISSN:0736-0266    

DOI:10.1002/jor.1100140409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractRegulation of postnatal growth of long bones occurs in multiple levels of chondrocytic activity, including stem cell proliferation, proliferative zone cycling, and regulation of changes in chondrocytic shape during hypertrophy. The differentiation sequence of chondrocytes is the same in all growth plates, but rates of elongation at a single point in time and over a period of time differ widely among individual growth plates, which suggests that the rates of sequential gene activation and suppression in this phenotypic pattern can vary. The purpose of this study was to investigate, directly andin vivo, parameters of the cell cycle of proliferative chondrocytes in growth plates growing at widely different rates at a single point in time in order to analyze the relationship between cell cycle time, including the duration of each phase of the cell cycle (G1, S, G2, and M), and the rate of growth. The experimental design used repeated pulse labeling with bromodeoxyuridine and was analyzed using a regression model of time of pulse label with increasing labeling index. Total cell cycle time was calculated as the inverse of the slope of the relationship of the labeling index and the time between labels. The y intercept was the calculated labeling index at time zero. Multiple comparison contrasts were used to test for individual differences among four growth plates with growth rates ranging from approximately 50 to 400 μm per 24 hours from 28‐day‐old rats. The estimate of total cell cycle time for the proximal tibial growth plate was 30.9 hours. Cell cycle times for the other three growth plates were 34.0, 48.7, and 76.3 hours for the distal radius, distal tibia and proximal radius, respectively. Although the times for the proximal tibia and distal radius did not differ significantly, all other times were significantly different (p<0.05) Almost all differences in total cell cycle time were attributable to significant differences in the length of the G1 phase. The S phase was estimated at 3.4–6.1 hours; the G2 phase, at 3.0 hours; and the M phase, at 0.5‐0.6 hours. The current study suggests that regulation through cell cycle parameters, specifically in the G1 phase, may be involved in overall regulation of differential postnatal long bone growth. It has previously been established that increase and shape change of cellular volume during hypertrophy may be regulated at the level of individual growth plates and that both are significant in understanding differential growth of long bone at this level. By demonstrating that chondrocytes in the proliferating zone have different cell cycle times that are regulated primarily through differences in the duration of G1, this study suggests that, in addition to systemic controls of chondrocyte proliferation, local controls may modulate rates of proliferation of individual growth plates and thus may be another locally mediated regulator of differentia

ISSN:0736-0266    

DOI:10.1002/jor.1100140410

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractCD44 has been described as a cell surface hyaluronan receptor present on a variety of different cells, and it is generally assumed to be prevalent in most connective tissues that contain hyaluronan. A major aim of this study was to test that presumption by localizing CD44 and hyaluronan within several tissues of the proximal tibia of the growing rat. Comparison of these profiles would reveal whether CD44 and hyaluronan co‐localize with high fidelity, as would be expected if CD44 were a major hyaluronan binding protein. Usingin situhybridization and immunohistochemistry, CD44 was identified on osteoclasts, chondroclasts, osteocytes, hematopoietic marrow cells, synovial cells, and connective tissue fibroblasts (ligaments, tendons, and fascia). Although the majority of osteocytes expressed CD44, reduced expression was observed for osteoblasts and osteoprogenitor cells. Additionally, CD44 was not detected on chondrocytes from epiphyseal and metaphyseal growth cartilages or in meniscal fibrocartilage. Using biotinylated G1 domain from aggrecan and link protein, hyaluronan was observed in the maturational and hypertrophic zones of all growth cartilages, the synovium and other fibroblastic connective tissues, regional areas of the periosteum and endosteum (around osteoblasts, osteoprogenitor cells, and osteoclasts), osteocyte lacunae, and surrounding blood vessels. In regions of co‐localization for CD44 and hyaluronan, it seems that CD44 is a likely hyaluronan binding protein in several tissues of the proximal tibia. However, it does not appear to be the predominant hyaluronan binding protein in growing cartilages of the weanling

ISSN:0736-0266    

DOI:10.1002/jor.1100140411

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY