Search

The extracellular matrix (eCM) of articular cartilage has several functions that are unique to joints. Although a technique for transplanting cultured chondrocytes has already been introduced, it is difficult to collect intact eCM when using enzymes to harvest samples. Temperature-responsive culture dishes have already been clinically applied in the fields of myocardial and corneal transplantation. Earlier studies have shown that a sheet of cultured cells with intact eCM and adhesive factors can be harvested using such culture dishes, which allow the surface properties of the dish to be reversibly altered by changing the temperature. Human chondrocytes were subjected to enzymatic digestion and then were seeded in temperature-responsive culture dishes. A sheet of chondrocytes was harvested by only reducing the temperature after the cultured cells reached confluency. A real-time PCR analysis of the chondrocyte sheets confirmed that type II collagen, aggrecan, and fibronectin were present. These results suggested that, although chondrocytes undergo dedifferentiation in a monolayer culture, multilayer chondrocyte sheets grown in a similar environment to that of three-dimensional culture may be able to maintain a normal phenotype. A histological examination suggested that multilayer chondrocyte sheets could thus prevent the loss of proteoglycans because the area covered by the sheets was well stained by safranin-O. The present experiments suggested that temperature-responsive culture dishes are useful for obtaining cultured chondrocytes, which may then be clinically employed as a substitute for periosteal patches because such sheets can be applied without a scaffold.

The aim of this study was to investigate the incidence and the mechanism of injuries and disorders in 122 windsurfers using questionnaires. The windsurfers were divided into four groups: course-racers, slalomers, wave-riders and beginners. The incidence of injuries of wave-riders(50%)was higher than that of course-racers (10%). The highest incidence of injuries in wave-riders was in the lower limbs. They tended to place their feet into the foot straps so tightly that they couldn't release them easily without twisting. Therefore, windsurfers should loosen the foot straps slightly to prevent injuries in the lower limbs. Lower back pain was the most common complaint in all windsurfers(64%). To prevent this, we recommend preparation of both suitable rig up and good physical condition. [ABSTRACT FROM AUTHOR]

Several combined procedures have been reported for treating recurrent patellofemoral instability (RPI) with various types and severity of morphological abnormalities, but none have identified absolute threshold values as indications for surgery. We performed medial patellofemoral ligament (MPFL) reconstruction combined with a modified Elmslie-Trillat (ET) procedure on 24 knees (10 male and 11 female patients) to treat RPI with morphological abnormalities corresponding to elevated tibial tubercle-trochlear groove (TT-TG) distance, significant patella alta, and trochlear dysplasia. The inclusion criteria were RPI with morphological abnormalities corresponding to one or more of the following: sulcus angle > 160 degrees, trochlear dysplasia of Dejour classification C or D, Caton-Deschamps index > 1.5, lateral shift ratio > 50%, congruence angle > 15 degrees, or TT-TG distance > 20 mm, including habitual dislocation of the patella. Skeletally immature patients and those with congenital dislocation of the patella were excluded. The Kujala score, International Knee Documentation Committee subjective score, Knee Injury and Osteoarthritis Outcome score (KOOS), and each item of the KOOS improved significantly after surgery. Patellar apprehension sign was present preoperatively in all cases, but all disappeared postoperatively. No instance of postoperative redislocation was observed. On radiographic examination, the mean Q angle, tilting angle, lateral shift ratio, congruence angle, Caton-Deschamps index, Insall-Salvati index, and TT-TG distance improved significantly after surgery. There were no significant differences in sulcus angle after surgery. These results suggest MPFL reconstruction combined with a modified ET procedure provides satisfactory outcomes based on radiological and clinical evaluations for RPI with morphological abnormalities corresponding to elevated TT-TG distance, significant patella alta, and trochlear dysplasia., Competing Interests: M.S. reports grants from Japan Agency for Medical Research and Development and personal fees from CellSeed, Inc., outside the submitted work., (Thieme. All rights reserved.)

Allogeneic cell therapies are not fully effective in treating osteoarthritis of the knee (OAK). We recently reported that transplantation of autologous chondrocyte cell-sheets along with open-wedge high tibial osteotomy promoted hyaline cartilage repair in humans. Here we describe our regenerative therapy for OAK using polydactyly-derived allogeneic chondrocyte cell-sheets (PD sheets) and temperature-responsive culture inserts. Ten patients with OAK and cartilage defects categorized arthroscopically as Outerbridge grade III or IV received the therapy. Cartilage viscoelasticity and thickness were assessed before and after transplantation. Arthroscopic biopsies obtained 12 months after transplantation were analyzed histologically. Gene expression was analyzed to evaluate the PD sheets. In this small initial longitudinal series, PD sheet transplantation was effective in treating OAK, as indicated by changes in cartilage properties. Gene marker sets in PD sheets may predict outcomes after therapy and provide markers for the selection of donor cells. This combined surgery may be an ideal regenerative therapy with disease-modifying effects in OAK patients., (© 2022. The Author(s).)

Background: Vessel injuries during total knee arthroplasty or high tibial osteotomy are rare but have serious complications. This study aimed to analyze the running position of the popliteal artery (PA) and branching level of the anterior tibial artery (ATA), using magnetic resonance imaging (MRI). This analysis might be helpful in avoiding unnecessary vessel injury., Methods: In total, 105 patients (41 men and 64 women), whose running position of the PA and branching level of the ATA could be detected by preoperative MRI, were included in this study. We configured zones A, B, C, and D to be 5-10, 15-20, 25-30 and 35-40 mm distal from the lateral tibial plateau in the axial view, respectively. First, the distance between the posterior cortex of the tibia and anterior border of the PA was measured. Second, the PA position from the medial border of the tibia was measured. This measured value was divided by the transverse diameter of the tibia, and multiplied by 100 to obtain the PA position from the medial border of the tibia. Third, the branching level of ATA was measured from the joint line. Subsequently, each value was compared between men (the M group) and women (the W group)., Results: The distance between the posterior cortex of the tibia and the anterior border of the PA was 5.5 ± 1.9, 10.4 ± 2.4, 12.5 ± 2.3 and 12.5 ± 2.3 (mm; mean ± SD) in zones A, B, C, and D, respectively. Comparing both groups, this distance was significantly larger (more separated posteriorly) in zones C and D in the M group. The PA position from the medial border of the tibia was 51.7 ± 6.5, 52.7 ± 8.2, 56.7 ± 10.5 and 66.8 ± 14 (%; mean ± SD) in zones A, B, C, and D, respectively. On comparing the two groups, this position was significantly larger (more laterally shifted) in zone D in the W group. The branching level of the ATA was not detected within 40 mm distal to the joint line in 92 patients (87.6%). However, it was detected within 40 mm (mean 32.5 mm; range 20-38) in 12 patients (11.4%). Among them, 11 were women. Only one woman had an aberrant branching pattern: the ATA bifurcated at the joint level., Conclusion: The PA positioned closest at the joint level, gradually separated and shifted laterally towards the distal side. The distance between the posterior cortex of the tibia and the anterior border of the PA was closer in women than in men in zones C and D. Although a difference of 2 mm is small, the risk of PA injury can be considered to be higher in women than in men. Furthermore, ATA injury is also a concern during retraction of the tibialis anterior muscle posteriorly, and the descending cut of the tibial tuberosity, particularly in women., Competing Interests: The authors have no conflicts of interest relevant to this article., (© 2022 Asia Pacific Knee, Arthroscopy and Sports Medicine Society. Published by Elsevier (Singapore) Pte Ltd.)

Background: Globally, total knee arthroplasty (TKA) is widely performed on patients with osteoarthritis. Meanwhile, open wedge high tibial osteotomy (OWHTO) has garnered attention in our country as a joint-preserving procedure. This study aimed to retrospectively compare the postoperative clinical outcomes of TKA and OWHTO for patients with osteoarthritis., Methods: We selected 94 patients (106 knees) who underwent OWHTO or TKA between 2013 and 2018, had complete clinical data, and were followed up for >2 years. Patients were classified into 2 groups depending on the procedure (TKA: n = 49; OWHTO: n = 45). Patients in the A (= arthroplasty) group were significantly older, with a worse range of motion (ROM) than those in the O (osteotomy) group. There were no significant differences regarding sex and body mass index between groups. Operative time, perioperative blood loss, knee ROM, and Japanese Knee Injury and Osteoarthritis Outcome Score (J-KOOS) were compared between the groups., Results: Significant differences were found between the A and O groups regarding operative time (120 ± 27.2 vs 80.3 ± 23.3 minutes), perioperative blood loss (505.4 ± 271.8 vs 322.6 ± 196.1 mL), knee ROM (flexion; 123.4 ± 16.3° vs 133.7 ± 12.8°), and J-KOOS for pain (87.4 ± 12.5 vs 78.1 ± 15.2 points) and symptoms (86.6 ± 12.3 vs 79.1 ± 13.3 points). There were no significant differences regarding other J-KOOS subscales., Conclusions: OWHTO involved shorter operative times and less blood loss. However, the O group reported less pain relief. The A group represents an older, likely less active patient population. Therefore, OWHTO is a possible joint-preserving treatment options in younger active patients who may not be interested in arthroplasty., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2020 The Authors.)

Introduction: Many warfarin-related genotypes have shown to impact the average daily warfarin (ADW) dose requirements; however, information in non-Caucasian populations is limited., Objectives: To identify the frequencies of 4 warfarin-related gene polymorphisms in an ethnically diverse patient population and to examine their impact with other clinical variables on ADW dose requirements., Methods: Patients were recruited from 2 anticoagulation clinics in the Los Angeles area. Blood samples were collected and genotyped for vitamin K epoxide reductase (VKORC1), CYP2C9*2, CYP2C9*3, and CYP4F2 after informed consent. Charts were reviewed to collect demographic, clinical, and warfarin dosing data., Results: A total of 291 patients were included (120 Caucasians, 127 Hispanics, and 44 Asians). In patients with wild-type genotypes for VKORC1, CYP2C9*2, CYP2C9*3, and CYP4F2, the highest warfarin requirement was found in Caucasians, lower in Hispanics, and lowest in Asians. Homozygous VKORC1 variant carriers were detected in 15%, 15%, and 79% in Caucasians, Hispanics, and Asians, respectively. Progressive lowering of ADW doses were associated with each VKORC1 variant in Caucasians and Hispanics, but the results in wild-type/ heterozygote Asians were unclear. CYP2C9 variants were associated with lower ADW doses; frequencies of CYP2C9*2 and CYP2C9*3 mutations were higher in Caucasians than in Hispanics but rare to none in Asians. The frequencies of CYP4F2 variant were similar across all ethnicities, but their impact on warfarin dose requirement were insignificant. Clinical factors such as age, body surface area, history of coronary artery disease, deep vein thrombosis or atrial fibrillation, and concomitant amiodarone or HMG-CoA reductase inhibitors had varying impact on the ADW requirements in the ethnicities studied., Conclusions: Our study demonstrated differences among 3 ethnic groups in terms of ADW dose requirements and the impact of associated clinical variables. The results suggest that a single model for all ethnicities may not provide the best performance in predicting warfarin dose requirements.

Current cartilage regenerative therapies are not fully effective in treating osteoarthritis of the knee (OAK). We have developed chondrocyte sheets for autologous transplantation and tested these in in vitro and in vivo preclinical studies, and have reported that the transplantation of chondrocyte sheets promoted hyaline cartilage repair in rat, rabbit, and minipig models. However, autologous transplantation of chondrocyte sheets has yet to be reported in humans. Here, we report our combination therapy in which conventional surgical treatment for OAK, is followed by autologous chondrocyte sheet transplantation for cartilage repair. Eight patients with OAK and cartilage defects categorized arthroscopically as Outerbridge grade III or IV receive the therapy. Patients are thoroughly assessed by preoperative and postoperative X-rays, magnetic resonance imaging (MRI), arthroscopy, Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm Knee Score (LKS), and a laser-induced photoacoustic method to assess cartilage viscoelasticity. Arthroscopic biopsies of all patients are performed 12 months after transplantation for histological evaluation. The properties of the chondrocyte sheets are evaluated using gene expression analysis to investigate the ability to predict the clinical and structural outcomes of the therapy. For this small initial longitudinal series, combination therapy is effective, as assessed by MRI, arthroscopy, viscoelasticity, histology, and the clinical outcomes of KOOS and LKS. Gene marker sets identified in autologous chondrocyte sheets may be predictive of the overall KOOS, LKS, and histological scores after therapy. These predictive gene sets may be potential alternative markers for evaluating OAK treatment., Competing Interests: Each author certifies that M.S. has been involved in the following relevant financial activities outside of this work and/or other relationships or activities that readers could perceive to have influenced, or that give the appearance of potentially influencing, this manuscript: Funding from CellSeed Inc. M.S. is one of the inventors on the patent (PCT/JP2006/303759) held by the applicants Tokai University and CellSeed Inc. for the manufacturing process of chondrocyte sheets. The other authors declare no competing interests.

Introduction: Cartilage regeneration is a promising therapy for restoring joint function in patients with cartilage defects. The limited availability of autologous chondrocytes or chondrogenic progenitor cells is an obstacle to its clinical application. We investigated the existence and chondrogenic potential of synovial membrane-derived multilineage-differentiating stress-enduring (Muse)-like cells as an alternative cell source for cartilage regeneration., Methods: Cells positive for stage-specific embryonic antigen-3 (SSEA-3), a marker of Muse cells, were isolated from the synovial membranes of 6 of 8 patients (median age, 53.5 years; range 36-72 years) by fluorescence-activated cell sorting. SSEA-3-positive cells were cultured in methylcellulose to examine their ability to form Muse clusters that are similar to the embryoid bodies formed by human embryonic stem cells. Muse clusters were expanded and chondrogenic potential of M-cluster-derived MSCs examined using a pellet culture system. Chondrogenic differentiation was evaluated by proteoglycan, safranin O, toluidine blue and type II collagen staining. To evaluate the practicality of the procedure for isolating Muse-like cells, we compared chondrogenic potential of M-cluster derived MSCs with expanded cells derived from the clusters formed by unsorted synovial cells., Results: Synovial membranes contained SSEA-3-positive cells that after isolation exhibited Muse-like characteristics such as forming clusters that expressed NANOG, OCT3/4, and SOX2. In the pellet culture system, cell pellets created from the M-cluster-derived MSCs exhibited an increase in wet weight, which implied an increase in extracellular matrix production, displayed metachromasia with toluidine blue and safranin O staining and were aggrecan-positive and type II collagen-positive by immunostaining. Unsorted synovial cells also formed clusters in methylcellulose culture, and the expanded cell population derived from them exhibited chondrogenic potential. The histological and immunohistochemical appearance of chondrogenic pellet created from unsorted synovial cell-derived cells were comparable with that from M-cluster-derived MSCs., Conclusions: Muse-like cells can be isolated from the human synovial membrane, even from older patients, and therefore may provide a source of multipotent cells for regenerative medicine. In addition, the cluster-forming cell population within synovial cells also has excellent chondrogenic potential. These cells may provide a more practical option for cartilage regeneration.

Background: Locomotive syndrome (LS) includes disorders of the musculoskeletal system and is a high-risk condition that requires nursing care. We included an examination of locomotive function in specific health checkups to investigate the relationship between LS risk and the muscle strengths. The purpose of this study was to determine the distribution of LS and the relationship between LS and metabolic syndrome (MetS)., Methods: Among 2695 participants who undertook a specific health checkup, 790 received a locomotive examination (302 men and 488 women; mean age, 65.9 years). Data for MetS components were measured in the specific health checkup. Data about the locomotive examination were obtained from five tests: the two-step test, stand-up test, 25-question Geriatric Locomotive Function Scale, and measurement of lower limb muscular strength and grip strength., Results: The MetS components did not differ according to LS risk level in men. In women, body weight, body mass index, and abdominal circumference were significantly lower in the non-LS group than in the LS risk level 1 or 2 groups. The ratio of lower limb muscular strength to body weight differed significantly between all risk groups in men and women. In women, lower limb muscular strength was significantly higher in those at risk of both LS and MetS (double-risk group) than in the LS-only group. In women, the ratio of lower limb muscular strength to body weight was significantly lower in the double-risk group than in the LS-only group., Conclusions: Adding a locomotive examination to the specific health checkup may be useful for identifying people at risk of LS or MetS. The prevalence rates of LS and MetS correlate positively in women. The ratio of lower limb muscular strength to body weight might be a better index of locomotor dysfunction than lower limb muscular strength alone., (Copyright © 2018 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

Endeavouring to repair and regenerate articular cartilage using cell sheets, we have previously established a co-culture system of chondrocytes and synoviocytes, and have reported the successful and rapid production of chondrocyte sheets. In the present study, to examine the effects of oxygen concentration on the chondrocyte sheets, we co-cultured human articular chondrocytes and human synoviocytes in 2%, 5% and 21% oxygen, and measured chondrocyte metabolic activity and proliferation activities under each condition for 14 days in culture. Layered chondrocyte sheets were also created under each condition and the proteoglycan (PG) level was compared with the gene expression of type I collagen (COL1), COL2, COL27, tissue metallopeptidase inhibitor 1 (TIMP1), fibronectin-1 (FN1), SRY-related HMG Box 9 (SOX9), aggrecan-1 (ACAN), integrin-α10 (ITGα10), matrix metalloproteinase 3 (MMP3), MMP13 and a disintegrin and metalloproteinase with thrombospondin motif 5 (ADAMTS5). Compared with 5% and 21% oxygen, the 2% condition caused significantly greater cell metabolic activity and proliferation (p < 0.05). The 2% condition produced a 10% greater PG level compared with 21% oxygen (p < 0.05). All conditions increased the expression of chondrocyte-specific genes, such as COL2, and were associated with low expression levels of catabolic factors, such as MMP3 and MMP13. These observations indicated that the specificity of the chondrocyte sheets was maintained under all conditions. The culture times did not differ between the 5% and 21% conditions. Compared with 21% oxygen, layered chondrocyte sheets rich in extracellular matrix were created 2.85 days earlier in 2% oxygen, which is similar to the level found in deep cartilage. Copyright © 2016 John Wiley & Sons, Ltd., (Copyright © 2016 John Wiley & Sons, Ltd.)

Many groups have reported good to excellent clinical outcomes of the Elmslie-Trillat (ET) procedure for recurrent dislocation of the patella. However, the mean follow-up period of these studies was no more than 5 years. We hypothesized that the long-term postoperative outcomes of the modified ET procedure for recurrent dislocation of the patella would be acceptable compared with those of other procedures. The long-term postoperative outcomes of patients treated with the modified ET procedure were examined. A total of 31 knees in 27 patients with recurrent dislocation of the patella who underwent a modified ET procedure (without medial capsular plication) were evaluated. The mean follow-up period was 13.0 years. Pre- and postoperative radiographs were examined to determine the Q-angle, tilting angle, lateral shift ratio, sulcus angle, congruence angle, and Insall-Salvati index. Clinical outcomes were evaluated based on the Fulkerson patellofemoral joint evaluation score, Kujala score, and the presence of the apprehension sign. Radiological evaluation revealed significant postoperative improvements in the Q-angle, tilting angle, lateral shift ratio, congruence angle, Kujala score, and Fulkerson score ( p  < 0.001). Sixty-eight percent of all patients had a "good" or "excellent" Fulkerson score. The apprehension sign continued to be shown for six knees. Progression of osteoarthritic changes was observed in three knees, and one knee was symptomatic. The modified ET procedure provided satisfactory outcomes based on radiological and clinical evaluations. These results show the long-term effectiveness and safety of the modified ET procedure for recurrent patellar dislocation., Competing Interests: Disclosure The authors report no conflicts of interest in this work., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Objective: The purpose of this study was to compare the clinical outcomes between patients with a valgus or varus deformity undergoing minimally invasive total knee arthroplasty through the medial approach., Methods: The patients were classified into 2 groups according to the preoperative femorotibial angle measured on an anteroposterior long leg roentgenogram. The valgus group comprised of 26 knees in 21 patients with a femorotibial angle <170° (163.5 ± 5.7), and the varus group comprised of 24 knees in 21 patients with a femorotibial angle >190° (195.9 ± 5.5). The following background variables were compared between the groups: age at the time of the operation, sex, causative disease, preoperative femoral mechanical-anatomical angle, and postoperative knee range of motion, Knee Society score, femorotibial angle, and implant position., Results: There were significant differences between the valgus and varus groups in the age (68.0 ± 6.9 vs 75.8 ± 6.2 years), percentage of males (23.8% vs 0%), percentage with rheumatoid arthritis (61.9% vs 4.8%), and preoperative femoral mechanical-anatomical angle (6.2 ± 1.0° vs 7.4 ± 2.1°). Clinical outcome variables of postoperative femorotibial angle (173.1 ± 3.9° vs 175.2 ± 1.6°) and α angle (96.6 ± 3.1° vs 95.0 ± 1.9°) also differed., Conclusion: It was assumed that over-valgus resection of the femur is a contributory factor to residual valgus alignment. However, knee range of motion and Knee Society score did not differ between the groups. We suggest that minimally invasive total knee arthroplasty through the medial approach is one of the treatment options for patients with valgus deformity.

Conventional culture methods using temperature-responsive culture dishes require 4-5 weeks to prepare layered chondrocyte sheets that can be used in articular cartilage repair and regeneration. This study investigated whether the use of synovial tissue obtained from the same joint as the chondrocyte nutritive supply source could more quickly facilitate the preparation of chondrocyte sheets. After culturing derived synoviocytes and chondrocytes together (i.e. combined culture or co-culture) on temperature-responsive inserts, chondrocyte growth was assessed and a molecular analysis of the chondrocyte sheets was performed. Transplantable tissue could be obtained more quickly using this method (average 10.5 days). Real-time polymerase chain reaction and immunostaining of the three-layer chondrocyte sheets confirmed the significant expression of genes critical to cartilage maintenance, including type II collagen (COL2), aggrecan-1 and tissue metallopeptidase inhibitor 1. However, the expression of COL1, matrix metalloproteinase 3 (MMP3), MMP13 and A-disintegrin and metalloproteinase with thrombospondin motifs 5 was suppressed. The adhesive factor fibronectin-1 (FN1) was observed in all sheet layers, whereas in sheets generated using conventional preparation methods positive FN1 immunostaining was observed only on the surface of the sheets. The results indicate that synoviocyte co-cultures provide an optimal environment for the preparation of chondrocyte sheets for tissue transplantation and are particularly beneficial for shortening the required culture period. Copyright © 2013 John Wiley & Sons, Ltd., (Copyright © 2016 John Wiley & Sons, Ltd.)

We have previously studied the effects of chondrocyte sheets on the repair and regeneration of articular cartilage by using temperature-responsive culture inserts. On the basis of this work, we succeeded in rapid fabrication of chondrocyte sheets with the use of a coculture method in which inserts were placed between synoviocytes and chondrocytes. Treatment of cartilage defects using layered chondrocyte sheets promotes repair and regeneration; this method is compatible with in vivo osteoarthritis models that reproduce partial-thickness defects. In human stem cell clinical research guidelines, the Ministry of Health, Labour and Welfare (MHLW) approved several applications related to this technology. Indeed, its translation to a clinical setting is already yielding favorable results. In this study, we evaluated the risk of tumorigenesis associated with this treatment and characterized the dynamics of biological processes associated with the posttransplantation cell sheets in vivo. Furthermore, we also confirmed the safety of the procedure by using array comparative genomic hybridization (array CGH) and G-band staining to screen for deleterious genetic aberrations during prolonged subculture of cells. The safety of chondrocytes that were cultured for longer than normal was confirmed by the array CGH and G-band staining results. In addition, tumorigenicity testing confirmed that culture chondrocyte sheets are not tumorigenic. Furthermore, from the evaluation of bioluminescence imaging following implantation of the cell sheets, it was confirmed that the transplanted chondrocytes and synoviocytes remained in the knee joint and did not transfer elsewhere over time. We believe that the technique used in this study is a highly useful method for evaluating the safety of not only chondrocytes but also extensive subculturing in general.

Background: T2 mapping is an MRI method particularly reflective of the collagen arrangement in the cartilage, and diffusion tensor (DT) imaging captures the diffusion of water molecules. Laser-induced photoacoustic measurement (LIPA) makes it possible to assess not only the thickness of the cartilage layer but also its viscoelastic properties. By assessing cartilage damage assessment using LIPA and 3.0 Tesla MRI (T2 mapping and DT imaging), this study investigates the usefulness of the various methods., Methods: The International Cartilage Repair Society (ICRS) classification was used to classify 29 bone cartilage pieces excised during surgical procedures. At the same time, LIPA was performed at sites matching the area of cartilage damage. MRI was performed preoperatively to measure the T2 and the apparent diffusion coefficient. In addition, tissue sections for histological assessment using the Mankin score were prepared for each ICRS grade, and the results with the various methods were compared., Results: With DT imaging, significant differences were observed in all grades (P < 0.01). With T2 mapping, significant differences were observed in all grades except for grade 1 versus grade 2 (P < 0.01). With LIPA, significant differences were observed in ICRS grade 1 versus grade 3 (P < 0.05), grade 1 versus grade 4 (P < 0.01), grade 2 versus grade 4 (P < 0.01), and grade 3 versus grade 4 (P < 0.05). With the Mankin score, significant differences were observed in ICRS grade 1 versus grade 3 (P < 0.01), grade 1 versus grade 4 (P < 0.01), grade 2 versus grade 4 (P < 0.01), and grade 3 versus grade 4 (P < 0.01). Correlations were observed in all combinations of ICRS grade with DT imaging, T2 mapping, LIPA, and Mankin score. Correlations were observed between the degree of histological degeneration and DT imaging, T2 mapping, and ICRS grade, but LIPA had a weaker correlation than MRI., Conclusions: In the assessment of knee osteoarthritis, there are instances where it is difficult to assess the damaged cartilage site with MRI alone, and we believe that it is desirable to use a combination of LIPA and MRI.

Background: Prevention and early detection of venous thromboembolism (VTE) is important after arthroplasty of the lower limb. The purpose of this study was to investigate the associations between VTE and hemostatic markers after minimally invasive total knee arthroplasty (MIS-TKA)., Methods: We performed a retrospective study of 50 patients (55 knees) who underwent primary unilateral MIS-TKA with periodic determination of D-dimer and soluble fibrin monomer complex (SFMC) concentrations and with ultrasonography. The development of symptomatic and asymptomatic VTE, location of deep venous thrombosis (DVT; proximal or distal), changes in SFMC and D-dimer concentrations, and correlations between hemostatic markers and VTE onset were evaluated., Results: Twenty-six patients (47%) had an asymptomatic distal DVT, but none had proximal DVT, pulmonary embolism, or symptomatic DVT. DVT was detected at postoperative day 1 (POD1) in 16 patients, POD3 in six, and POD5 in three (excluding detections of the same DVT in the same position on different days). DVT onset correlated significantly with SFMC concentration on POD1 and with D-dimer concentration on POD3. The D-dimer concentration did not differ significantly between patients who developed DVT (DVT+) and those who did not (DVT-) at each postoperative time. SFMC concentration differed between DVT+ and DVT- patients only on POD1. Analysis of each hemostatic marker classified as either within or outside the normal concentration range showed no significant correlations between D-dimer concentration and DVT onset at each period. There were significant correlations between SFMC concentrations and DVT onset on POD1 and POD3. There were also significant correlations between D-dimer positive (+) findings and/or SFMC+ findings and DVT onset on POD1 and POD3. D-dimer+ and/or SFMC+ findings had better specificity on POD1 and a positive predictive value on POD1 and POD3 compared with SFMC+ alone., Conclusions: SFMC concentration is an effective hemostatic marker for early detection of DVT. D-dimer concentration alone has limited value as a hemostatic marker for early detection of DVT. Measurement of both D-dimer and SFMC concentrations might be a more sensitive diagnostic tool than measuring SFMC concentration alone.

Background: In the present study, we measured damaged areas of cartilage with diffusion tensor (DT) imaging and T2 mapping, and investigated the extent to which cartilage damage could be determined using these techniques., Methods: Forty-one patients underwent arthroscopic knee surgery for osteoarthritis of the knee, a meniscus injury, or an anterior cruciate ligament injury. Preoperative magnetic resonance imaging of the knee was performed, including T2 mapping and diffusion tensor imaging. The presence of cartilage injury involving the medial and lateral femoral condyles and tibia plateau was assessed during surgery using the Outerbridge scale. The ADC, T2 values and fractional anisotropy of areas of cartilage injury were then retrospectively analysed., Results: The ADC results identified significant differences between Outerbridge grades 0 and 2 (P = 0.041); 0 and 3 (P < 0.001); 1 and 2 (P = 0.045); 1 and 3 (P < 0.001); and 2 and 3 (P = 0.028). The FA results identified significant differences between grades 0 and 1 (P < 0.001); 0 and 2 (P < 0.001); and 0 and 3 (P < 0.001). T2 mapping identified significant differences between Outerbridge grades 0 and 2 (P = 0.032); 0 and 3 (P < 0.001); 1 and 3 (P < 0.001); and 2 and 3 (P < 0.001). Both the T2 mapping (R(2) = 0.7883) and the ADC (R(2) = 0.9184) correlated significantly with the Outerbridge grade. The FA (R(2) = 0.6616) correlated slightly with the Outerbridge grade., Conclusions: T2 mapping can be useful for detecting moderate or severe cartilage damage, and the ADC can be used to detect early stage cartilage damage. The FA can also distinguish normal from damaged cartilage.

Development of tissue-engineered materials to treat anterior cruciate ligament (ACL) injury has been limited by the lack of phenotypic markers. We investigated the feasibility of inducing ACL regeneration using cell sheet technology based on the expression of tenomodulin (TNMD) as an early phenotypic marker of ligaments. ACL remnants, the synovium surrounding cruciate ligaments (SCL), the synovium surrounding the infrapatellar fat pads (SIF), and subcutaneous fat tissue (SCF) were obtained from patients undergoing ACL reconstruction or total knee arthroplasty. ACL cell sheets and SCL-derived cell sheets were fabricated successfully A three-dimensional bioengineered ACL was generated by combining triple-layered ACL cell sheets with a bioabsorbable mesh composite. Immunohistochemical examination showed that TNMD was expressed in human ACL fibers, triple-layered ACL cell sheets, ACL remnants, SCL, and SIF, but not in SCF. Real-time PCR showed that TNMD mRNA was expressed at substantially higher levels in the ACL, SCL, and SIF than in the SCF. These results suggest that TNMD is a specific marker of the human ACL and that ACL sheets have a phenotype similar to that of the ACL. The greater expression of TNMD in the SCL- and SIF- suggests that the synovium is a potential cell source for ACL regeneration., (© 2013 Wiley Periodicals, Inc.)

In anatomic anterior cruciate ligament (ACL) reconstruction, several pitfalls in creating the femoral bone tunnels at the correct position are of great concern. Our new method, the tibia rotational (TR) technique, may contribute to resolving these. The purpose of this study is to describe further details about the TR technique in anatomic double-bundle ACL reconstruction. Both anteromedial and posterolateral femoral bone tunnels were drilled through a posterolateral tibial bone tunnel using tibial rotation without deep knee flexion. When it is difficult to reach the mark with the rigid guide pin, the narrow curved TR technique guide and the flexible drill system allow drilling femoral bone tunnels in the correct position. The TR technique offers the technical ease required for widespread acceptance while prioritizing the fundamental goals of an anatomic double-bundle ACL reconstruction.

In this study, we investigate the effects of treatment with layered chondrocyte sheets and synovial cell transplantation. An osteochondral defect was created of 48 Japanese white rabbits. In order to determine the effects of treatment, the following 6 groups were produced: (A) synovial cells (1.8 × 10(6) cells), (B)layered chondrocyte sheets (1.7 × 10(6) cells), (C) synovial cells (3.0 × 10(5) cells) + layered chondrocyte sheets, (D)synovial cells (6.0 × 10(5) cells) + layered chondrocyte sheets, (E)synovial cells (1.2 × 10(6) cells) + layered chondrocyte sheets, (F) osteochondral defect. Layered chondrocyte sheets and synovial cells were transplanted, sacrificed four and 12 weeks postoperatively. An incapacitance tester (Linton) was used to find trends in the weight distribution ratio of the damaged limbs after surgery. Sections were stained with Safranin-O. Repair sites were evaluated using ICRS grading system. In groups (A) to (E), the damaged limb weight distribution ratio had improved. The repair tissue stained positively with Safranin-O. Four and 12 weeks after surgery, groups (A) to (E) exhibited significantly higher scores than group (F), and groups (D) and (E) exhibited significantly higher scores than groups (A) and (B). This suggests the efficacy of combining layered chondrocyte sheets with synovial cells., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Lacking a blood supply and having a low cellular density, articular cartilage has a minimal ability for self-repair. Therefore, wide-ranging cartilage damage rarely resolves spontaneously. Cartilage damage is typically treated by chondrocyte transplantation, mosaicplasty or microfracture. Recent advances in tissue engineering have prompted research on techniques to repair articular cartilage damage using a variety of transplanted cells. We studied the repair and regeneration of cartilage damage using layered chondrocyte sheets prepared on a temperature-responsive culture dish. We previously reported achieving robust tissue repair when covering only the surface layer with layered chondrocyte sheets when researching partial-thickness defects in the articular cartilage of domestic rabbits. The present study was an experiment on the repair and regeneration of articular cartilage in a minipig model of full-thickness defects. Good safranin-O staining and integration with surrounding tissues was achieved in animals transplanted with layered chondrocyte sheets. However, tissue having poor safranin-O staining-not noted in the domestic rabbit experiments-was identified in some of the animals, and the subchondral bone was poorly repaired in these. Thus, although layered chondrocyte sheets facilitate articular cartilage repair, further investigations into appropriate animal models and culture and transplant conditions are required., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: Like all mammalian cells, normal adult chondrocytes have a limited replicative life span, which decreases with age. To facilitate the therapeutic use of chondrocytes from older donors, a method is needed to prolong their life span., Methods: We transfected chondrocytes with hTERT or GRP78 and cultured them in a 3-dimensional atelocollagen honeycomb-shaped scaffold with a membrane seal. Then, we measured the amount of nuclear DNA and glycosaminoglycans (GAGs) and the expression level of type II collagen as markers of cell proliferation and extracellular matrix formation, respectively, in these cultures. In addition, we allografted this tissue-engineered cartilage into osteochondral defects in old rabbits to assess their repair activity in vivo., Results: Our results showed different degrees of differentiation in terms of GAG content between chondrocytes from old and young rabbits. Chondrocytes that were cotransfected with hTERT and GRP78 showed higher cellular proliferation and expression of type II collagen than those of nontransfected chondrocytes, regardless of the age of the cartilage donor. In addition, the in vitro growth rates of hTERT- or GRP78-transfected chondrocytes were higher than those of nontransfected chondrocytes, regardless of donor age. In vivo, the tissue-engineered cartilage implants exhibited strong repairing activity, maintained a chondrocyte-specific phenotype, and produced extracellular matrix components., Conclusions: Focal gene delivery to aged articular chondrocytes exhibited strong repairing activity and may be therapeutically useful for articular cartilage regeneration.

Background: Although the clinical results of autologous chondrocyte implantation for articular cartilage defects have recently improved as a result of advanced techniques based on tissue engineering procedures, problems with cell handling and scaffold imperfections remain to be solved. A new cell-sheet technique has been developed, and is potentially able to overcome these obstacles. Chondrocyte sheets applicable to cartilage regeneration can be prepared with this cell-sheet technique using temperature-responsive culture dishes. However, for clinical application, it is necessary to evaluate the characteristics of the cells in these sheets and to identify their similarities to naive cartilage., Results: The expression of SOX 9, collagen type 2, 27, integrin alpha 10, and fibronectin genes in triple-layered chondrocyte sheets was significantly increased in comparison to those in conventional monolayer culture and in a single chondrocyte sheet, implying a nature similar to ordinary cartilage. In addition, immunohistochemistry demonstrated that collagen type II, fibronectin, and integrin alpha 10 were present in the triple-layered chondrocyte sheets., Conclusion: The results of this study indicate that these chondrocyte sheets with a consistent cartilaginous phenotype and adhesive properties may lead to a new strategy for cartilage regeneration.

Some treatments for full thickness defects of the articular cartilage, such as the transplantation of cultured chondrocytes have already been performed. However, in order to overcome osteoarthritis, we must further study the partial thickness defects of articular cartilage. It is much more difficult to repair a partial thickness defect because few repair cells can address such injured sites. We herein show that bioengineered and layered chondrocyte sheets using temperature-responsive culture dishes may be a potentially useful treatment for the repair of partial thickness defects. We also show that a chondrocyte-plate using a rotational culture system without the use of a scaffold may also be useful as a core cartilage of an articular cartilageous defect. We evaluated the properties of these sheets and plates using histological findings, scanning electrical microscopy, and photoacoustic measurement methods, which we developed to evaluate the biomechanical properties of tissue-engineered cartilage. In conclusion, the layered chondrocyte sheets and chondrocyte-plates were able to maintain the cartilageous phenotype, thus suggesting that they could be a new and potentially effective therapeutic product when attached to the sites of cartilage defects.

The specific aim of our investigation is to study the potential use of a collagen/heparin-carrying polystyrene (HCPS) composite extracellular matrix for articular cartilage tissue engineering. Here, we created a high-performance extracellular matrix (HpECM) scaffold to build an optimal extracellular environment using an HCPS we originally developed, and an atelocollagen honeycomb-shaped-scaffold (ACHMS-scaffold) with a membrane seal. This scaffold was coated with HCPS to enable aggregation of heparin-binding growth factors such as FGF-2 and TGF-beta1 within the scaffold. Three-dimensional culture of rabbit articular chondrocytes within the HpECM-scaffold and subsequent preparation of a tissue-engineered cartilage were investigated. The results showed remarkably higher cell proliferative activity within the HpECM-pretreated-FGF-2 scaffold and the sustenance of phenotype within the HpECM-pretreated-TGF-beta1 scaffold. It was thought that both FGF-2 and TGF-beta1 were stably immobilized in the HpEMC-scaffold since HCPS generated an extracellular environment similar to that of heparan sulfate proteoglycan within the scaffold. These results suggest that an ACHMS-scaffold immobilized with HCPS can be a HpECM for cartilage regeneration to retain the heparin-binding growth factors within the scaffolds.

Some treatments for full thickness defects of articular cartilage, such as cultured chondrocyte transplantation, have already been done. However, to overcome osteoarthritis, we must further study the partial thickness defect of articular cartilage. It is much more difficult to repair a partial thickness defect because few repairing cells can address such injured sites. We herein show that bioengineered layered chondrocyte sheets using temperature-responsive culture dishes may be a potentially useful treatment for partial thickness defects. We evaluated the property of these sheets using real-time PCR and histological findings, and allografted these sheets to evaluate the effect of treatment using a rabbit partial model. In conclusion, layered chondrocyte sheets were able to maintain the cartilageous phenotype, and could be attached to the sites of cartilage damage which acted as a barrier to prevent a loss of proteoglycan from these sites and to protect them from catabolic factors in the joint.

Background and Objectives: We demonstrated that photoacoustic measurement enables viscoelastic characterization of biological tissue. The purpose of this study was to develop a practical photoacoustic measurement system for diagnosis of osteoarthritis (OA) by viscoelastic characterization of articular cartilage., Study Design/materials and Methods: The portable system consists of a commercially available 3rd harmonic Q-switched Nd:YAG laser as a light source and a transducer, which is arranged coaxially with an optical fiber. Cell proliferation tests were performed to study the effect of laser irradiation on chondrocytes. Photoacoustic measurements were performed using enzymatically treated cartilage as a model of OA., Results: There was no significant damage of chondrocytes caused by laser irradiation (100 microJ/mm2, 5 Hz, 30 shots). The change in relaxation times measured by the photoacoustic measurement had a positive correlation with time of enzymatic treatment, that is, the degree of cartilage degeneration., Conclusions: We have developed a noninvasive photoacoustic measurement system designed for arthroscopic use and have demonstrated the applicability of this system to the diagnosis of OA-like cartilage degeneration., (2006 Wiley-Liss, Inc.)

The pharmacokinetics of various drugs may be profoundly altered during different stages of pregnancy, parturition, and lactation. Gastrointestinal absorption or bioavailability of drugs may vary due to changes in gastric secretion and motility. Various haemodynamic changes such as an increase in cardiac output, blood volume, and renal plasma flow may affect drug disposition and elimination. The increase in blood volume and total body water which occurs during pregnancy can alter the volume of distribution for various drugs. Although exact quantifications are not easy, these changes in pharmacokinetic parameters should be considered when dosing antiarrhythmic agents in pregnant women. Plasma protein concentrations and drug binding capacity are altered in the mother and fetus as pregnancy advances. With highly protein bound drugs, these changes may be clinically significant, as the pharmacological efficacy and toxicity are presumed to be related to the concentration of free drug in both the mother and fetus. In some instances, the fetus may be susceptible to greater drug toxicity as free drug concentrations may be underestimated by measurement of total drug concentrations. Changes in maternal drug metabolism and metabolism by the fetoplacental unit also contribute to alterations in the pharmacokinetics of drugs. As the placenta contains many metabolising enzymes, biotransformation of drugs at this site could potentially convert a drug into an active metabolite, or prevent fetal exposure to a toxic drug. Placental transfer of drugs, leading to toxicity in the fetus, is a major concern in the pharmacological management of the pregnant patient. The passage of individual drugs will vary depending on their apparent volumes of distribution, degree of protein binding the rates of metabolic conversion and excretion within the placenta and fetus, the pH difference between the maternal and fetal fluids, and maternal haemodynamic changes. Drug properties such as lipid solubility, protein binding characteristics, and ionisation constant (pKa) also influence the placental passage of drugs. For weakly basic antiarrhythmic agents, the fetal drug concentration may potentially exceed the maternal plasma concentration when the fetal pH is lowered as in the case of fetal acidosis; this is due to 'ion trapping'. Additionally, higher free drug concentrations of these basic drugs may exist, due to decreased alpha 1-acid glycoprotein concentration and binding affinity in the fetus. Lignocaine (lidocaine) has been shown to enter fetal plasma rapidly with fetal-maternal concentration ratios in the range of 0.52 to 0.66.(ABSTRACT TRUNCATED AT 400 WORDS)

Serious valve-related complications that occur in patients with prosthetic valves have been discussed. The emergency physician's role primarily is to recognize the high probability that one of these serious complications exists and hospitalize the patient so that rapid definitive diagnoses and therapeutic decisions are not delayed.

In this paper the results of the clinicopathological study on a total of 79 bladder tumor cases are presented. They are principally related to the stromal proliferation or branching of the tumors. The tumor cases consist of those with a good prognosis as well as those with a poor prognosis. In the former category there are 61 cases with a long survival history (with or without recurrence); the remainder (18 cases) had a history of a short survival (dying within 2 years). Histologically there was a marked difference in the regularity of the stromal branching of the tumor between those cases with a long survival history and those cases with a short survival history. In the former group the regular type of stromal branching was predominant; in the latter group the irregular type was predominant.