header advert
Results 1 - 9 of 9
Results per page:
Bone & Joint Research
Vol. 11, Issue 10 | Pages 715 - 722
10 Oct 2022
Matsuyama Y Nakamura T Yoshida K Hagi T Iino T Asanuma K Sudo A

Aims

Acridine orange (AO) demonstrates several biological activities. When exposed to low doses of X-ray radiation, AO increases the production of reactive radicals (radiodynamic therapy (AO-RDT)). We elucidated the efficacy of AO-RDT in breast and prostate cancer cell lines, which are likely to develop bone metastases.

Methods

We used the mouse osteosarcoma cell line LM8, the human breast cancer cell line MDA-MB-231, and the human prostate cancer cell line PC-3. Cultured cells were exposed to AO and radiation at various concentrations followed by various doses of irradiation. The cell viability was then measured. In vivo, each cell was inoculated subcutaneously into the backs of mice. In the AO-RDT group, AO (1.0 μg) was locally administered subcutaneously around the tumour followed by 5 Gy of irradiation. In the radiation group, 5 Gy of irradiation alone was administered after macroscopic tumour formation. The mice were killed on the 14th day after treatment. The change in tumour volume by AO-RDT was primarily evaluated.


Introduction and Objective

Achilles tendon defect is difficult problem for orthopedic surgeon, and therefore the development of new treatments is desirable. Platelet-rich fibrin (PRF), dense fibrin scaffold composed of a fibrin matrix containing many growth factors, is recently used as regenerative medicine preparation. However, few data are available on the usefulness of PRF on Achilles tendon healing after injury. The objective of this study is to examine whether PRF promotes the healing of Achilles tendon defect in vivo and evaluated the effects of PRF on tenocytes in vitro.

Materials and Methods

PRF were prepared from rats according to international guidelines on the literature. To create rat model for Achilles tendon defect, a 4-mm portion of the right Achilles tendon was completely resected, and PRF was placed into the gap in PRF group before sewing the gap with nylon sutures. To assess the histological healing of Achilles tendon defect, Bonar score was calculated using HE, Alcian-blue, and Picosirius-red staining section. Basso, Beattie, Bresnahan (BBB) score was used for the evaluation of motor functional recovery. Biomechanical properties including failure tensile load, ultimate tensile stress, breaking elongation, and elastic modulus were measured. We examined the effects of PRF on tenocytes isolated from rat Achilles tendon in vitro. The number of viable cells were measured by MTS assay, and immunostaining of ki-67 was used for detection of proliferative cells. Migration of tenocytes was evaluated by wound closure assay. Protein or gene expression level of extracellular matrix protein, such as collagen, were evaluated by immunoblotting, immunofluorescence, or PCR. Phosphorylation level of AKT, FGF receptor, or SMAD3 was determined by western blotting. Inhibitory experiments were performed using MK-2206 (AKT inhibitor), FIIN-2 (FGFR inhibitor), SB-431542 (TGF-B receptor inhibitor), or SIS3 (SMAD3 inhibitor). All p values presented are two-sided and p values < 0.05 were considered statistically significant.


Bone & Joint Research
Vol. 9, Issue 11 | Pages 821 - 826
1 Nov 2020
Hagi T Nakamura T Kita K Iino T Asanuma K Sudo A

Aims

Tocilizumab, an interleukin-6 (IL-6) receptor (IL-6R) targeting antibody, enhances the anti-tumour effect of conventional chemotherapy in preclinical models of cancer. We investigated the anti-tumour effect of tocilizumab in osteosarcoma (OS) cell lines.

Methods

We used the 143B, HOS, and Saos-2 human OS cell lines. We first analyzed the IL-6 gene expression and IL-6Rα protein expression in OS cells using reverse transcription real time quantitative-polymerase chain reaction (RT-qPCR) analysis and western blotting, respectively. We also assessed the effect of tocilizumab on OS cells using proliferation and invasion assay.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 32 - 32
1 Jan 2016
Hasegawa M Miyamoto N Miyazaki S Wakabayashi H Sudo A
Full Access

Introduction

Pseudotumors have been reported following metal-on-metal total hip arthroplasty (THA); however, the natural history and longitudinal imaging findings of pseudotumors have yet to be fully analyzed. Our hypothesis was that pseudotumor size might change over time following metal-on-metal THA. This hypothesis was studied longitudinally using magnetic resonance imaging (MRI).

Materials and Methods

Screening for pseudotumors was performed using MRI after large-diameter metal-on-metal THA. Initial MRI was conducted at a mean of 36 months postoperatively. Follow-up MRI was performed at a mean of 20 months after the detection of 24 pseudotumors in 20 asymptomatic patients. Pseudotumors were classified as cystic, solid, and mixed types. Fourteen hips were characterized as cystic type and 10 hips were defined as mixed type. There were three men and 17 women with a mean age of 63 years. Pseudotumor size was determined on MRI by manually outlining the greatest size of the mass. Serum cobalt and chromium ion levels were measured in nine patients with unilateral THA at the time of MRI. Statistical analysis was performed using the Kruskal-Wallis test and chi square test to compare age, gender, BMI, head diameter, cup inclination, cup anteversion, and pseudotumor type among changes of pseudotumor size. We compared the pseudotumor size for the three groups (increase in size, no change, decrease in size) using Kruskal-Wallis test and Mann-Whitney U test. Wilcoxon signed-rank test was used to compare median serum metal ion levels over time. A p value < 0.05 was considered significant. This study was approved by the ethics committee of our institution, and all patients provided informed consent.


Bone & Joint Research
Vol. 4, Issue 5 | Pages 84 - 92
1 May 2015
Hamamura K Nishimura A Iino T Takigawa S Sudo A Yokota H

Objectives

Salubrinal is a synthetic agent that elevates phosphorylation of eukaryotic translation initiation factor 2 alpha (eIF2α) and alleviates stress to the endoplasmic reticulum. Previously, we reported that in chondrocytes, Salubrinal attenuates expression and activity of matrix metalloproteinase 13 (MMP13) through downregulating nuclear factor kappa B (NFκB) signalling. We herein examine whether Salubrinal prevents the degradation of articular cartilage in a mouse model of osteoarthritis (OA).

Methods

OA was surgically induced in the left knee of female mice. Animal groups included age-matched sham control, OA placebo, and OA treated with Salubrinal or Guanabenz. Three weeks after the induction of OA, immunoblotting was performed for NFκB p65 and p-NFκB p65. At three and six weeks, the femora and tibiae were isolated and the sagittal sections were stained with Safranin O.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_VIII | Pages 34 - 34
1 Mar 2012
Hasegawa M Kawamura G Wakabayashi H Sudo A Uchida A
Full Access

Introduction

Standard surgical exposure reduces blood flow to the patella during total knee arthroplasty (TKA). Reduction of patellar blood flow has resulted in patellofemoral complications including osteonecrosis and patellar fracture, necessitating revision surgery. Eversion of the patella is typically used to gain access to the knee joint in most TKA surgical approaches. More recently, the development of minimally invasive surgery (MIS) techniques has avoided patellar eversion by subluxing the patella. The present study is the first to measure patellar blood flow during MIS TKA with the knee in both extension and 90 degrees of flexion followed by lateral retraction and then eversion of the patella.

Methods

Patellar blood flow was measured using laser Doppler flowmetry in 40 patients during MIS TKA. Patients included 32 women and 8 men who had a mean age of 73 years (range, 52 to 88 years) and a mean weight of 59 kg (39 to 85 kg). The pre-operative diagnoses were osteoarthritis in 36 patients and rheumatoid arthritis in four patients. All patients underwent MIS TKA using the mini-midvastus approach. After initial blood flow was assessed with the leg in full extension, further measurements were performed after lateral retraction and after eversion of the patella. Then, blood flow was assessed with the knee in 90 degrees of flexion followed by lateral retraction and then eversion of the patella.


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_III | Pages 469 - 469
1 Sep 2009
Yuasa K Ito Y Baldini N Sudo A Uchida A
Full Access

Osteoporosis is one of the most common diseases in modern aging society. Receptor activator of nuclear factor-κB ligand (RANKL) plus macrophage colony stimulating factor (M-CSF)-mediated osteoclastogenesis has been recently implicated in the pathogenesis of this disease. Among other causes, the anticoagulant drug heparin is a notable inducer of secondary osteoporosis, although the molecular pathway underlying this process, particularly in human model, has not been clarified yet. Recently, we reported the differentiation of two subtypes of osteoclasts starting from human peripheral blood CD14-positive monocytes (Monocytes), respectively fusion regulatory protein-1 (FRP-1/CD98)-mediated osteoclasts and RANKL+M-CSF-mediated osteoclasts. We, therefore, investigated in details effects of heparin on differentiation and activation using a simple system of human osteoclastogenesis.

When Monocytes were cultured with osteoclastogenesis-relating factors and a high dose of heparin, heparin suppressed osteoclastogenesis in both pathways. However, a proper quantity of heparin enhanced tartrate-resistant acid phosphatase-positive multinucleated giant cell formation. There were significant differences in fusion indices between control osteoclasts and osteoclasts stimulated by moderate concentrations of heparin in two systems (P< 0.05). As a result of osteoclastic activity, FRP-1-mediated osteoclasts treated with a proper quantity of heparin formed larger pits on Ca plates. Moreover, lacunae on dentin surfaces induced by FRP-1-mediated osteoclasts were enhanced with moderate concentration of heparin. In contrast, heparin did not increase pit-formation area on Ca plates and on dentin surfaces by RANKL+M-CSF-mediated osteoclasts. Evaluating the relation between the concentration of heparin and the osteolytic areas on Ca plates, Pearson’s correlation coefficient of the FRP-1 and the RANKL+M-CSF were −0.973 (P< 0.05) and −0.695 (P=0.19), respectively.

In present study, although moderate doses of heparin stimulated differentiation in both systems, in osteoclastic activity, heparin promoted only to the FRP-1 system, not to RANKL+M-CSF system. Our results suggested FRP-1-induced osteoclastogenesis mainly contributes to development of heparin osteoporosis and also that the onset mechanism after long-term administration of heparin may be affected by the characteristic bone resorption ability of FRP-1osteoclasts.


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_III | Pages 251 - 251
1 Nov 2002
Shi D Sudo A
Full Access

Objectives: Post-operative deep vein thrombosis (DVT) is considered uncommon in Japanese. Numerous reports of pulmonary embolism (PE) have been reported in the last few decades, and although thrombo-embolic diseases appear to be increasing, the incidence of DVT and PE in Japan have not been investigated thoroughly. We studied the incidence of proximal DVT and PE in Japanese patients who had total hip arthroplasty (THA) and total knee arthroplasty (TKA).

Patients and Methods: Between October 1996 and November 2000, we performed THA on 99 patients and TKA on 75 patients at Mie University Hospital. All were included in this study. They were routinely examined for proximal DVT by ultrasonography before and after their operation. Those patients who had ultrasonographic findings of DVT were also investigated for PE by ventilation-perfusion lung scan.

Results and Discussion: No patient had a DVT before surgery. Fourteen patients had post-operative DVT, detected by ultrasonography, and confirmed by venography. 12 cases were females and 2 cases were males. There were 5 cases of PE among the fourteen cases of DVT, The symptomayic PE were 2 cases, and non-incidence of PE were 3 cases. The incidence of DVT was 5.2% on the left side and 4.0% on the right side.The incidence of DVT was 11.2% in THA, and 4.0% in TKA, while that of PE was 5.0% in THA and 0% in TKA. These results suggest that DVT and PE in Japan are lower than those of white races.


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_III | Pages 233 - 233
1 Nov 2002
Sudo A Komeno M Seto M Kato K Uchida A
Full Access

Antibiotic-impregnated polymethylmethacrylate beads, which are used to deliver antibiotic directly to infected sites in the musculoskeletal system has been evaluated most widely. The disadvantages include reduced biocompatibility with bone, short duration of drug release, very low release rate and thermal damage to the antibiotics. For solving this problem, we developed the antibiotic-impregnated calcium hydroxyapatite ceramic implant (HA) as a new drug delivery system. This study is to evaluate the clinical results of the antibiotic-impregnated HA used for the treatment of infected total hip and knee arthroplasty. Twenty-two patients with infected arthroplasty treated antibiotic-impregnated HA were evaluated. There were 5 men and 17 women with a median age of 65 (range, 54–86 years). The study included 14 hips and 8 knees. The duration from the initial arthroplasty to the detection of the infection was 16 years at the longest (median of 2 years and 2 months). The most common microorganism was Staphylococcus aureus, presented in 13 patients. Antibiotic most frequently impregnated was Vancomycin. In five patients, debridement without removal of the prosthesis was performed with antibiotic-impregnated HA implanted in surrounding bone. In another three patients, one-stage revision was performed with antibiotic-impregnated HA. In fourteen patients, antibiotic-impregnated HA was used to fill the dead space after removal of the prosthesis (two-stage revision was performed in 9 patients). No patients developed evidence of recurrent infection at an average follow-up of 18.7 months. Antibiotic-impregnated HA is an excellent drug delivery system for the infected total hip and knee arthroplasty.