Takashi Imagama

Regulation of nitric oxide generation by up-regulated arginase I in rat spinal cord injury

Recently, arginase is suggested to regulate nitric oxide production by competing with nitric oxide synthase for the same substrate, L-arginine, in experimental asthma. We investigated the role of arginase and its relationship to nitric oxide production after spinal cord injury. Rats were subjected to laminectomy and complete transection of their spinal cords (injury group) or laminectomy only (sham group). In the injury group, arginase I was increased in the macrophages at the transection edge, and the peak was observed 48 h after spinal cord injury. However, nitric oxide production decreased significantly in the injury group despite increased nitric oxide synthase2 mRNA expression compared with the sham group. We also demonstrated the reduction in L-arginine concentrations, which was inversely associated with changes in arginase activity. Therefore, arginase appeared to regulate nitric oxide production by consuming L-arginine. The regulation of arginase activity and L-arginine levels may improve nitroxidative stress and reduce tissue damage in spinal cord injury.

Preparation and Characterization of a Polyclonal Antibody against Brominated Protein

(Di)bromotyrosine is formed by the specific reaction of eosinophil peroxidase and can be used as an eosinophil activation marker. In the present study, an antibody for (di)bromotyrosine in proteins was prepared to investigate the pathogenesis of eosinophil-related diseases such as allergic responses. A rabbit polyclonal antibody was raised against brominated keyhole limpet hemocyanin. The specificity of the antiserum was investigated with an enzyme-linked immunosorbent assay (ELISA). The antiserum recognized brominated bovine serum albumin (BSA) and dibromotyrosine-conjugated BSA. The antiserum also reacted with chlorinated BSA and di-iodotyrosine-conjugated BSA. Moreover, the specificity of the antiserum was investigated using competitive ELISA. Dibromotyrosine and di-iodotyrosine inhibited the recognition of brominated BSA by the antiserum. However, the recognition of brominated BSA by the antiserum was not inhibited by bromotyrosine, chlorotyrosine, iodotyrosine, nitrotyrosine, aminotyrosine, phosphotyrosine, or tyrosine. These results suggested that the epitope of the antiserum is dihalogenated tyrosine. Immunohistochemically, the antiserum stained brominated rat eosinophils but not chlorinated or nitrated eosinophils. In conclusion, an antiserum for dihalogenated protein was prepared. It is expected that the antiserum will be useful for the analysis of the pathogenesis of allergic diseases such as asthma and atopic dermatitis.

Rotational Acetabular Osteotomy for Habitual Hip Dislocation With Posterior Acetabular Wall Deficiency in Patients With Down Syndrome

Hip dislocation associated with Down syndrome is relatively rare. Hip dislocation can progress to severe subluxation or habitual dislocation if the initial therapy is improperly performed. However, definitive treatment guidelines for conservative and surgical therapy for hip dislocation in patients with Down syndrome have not been established. This article describes a case of a 12-year-old girl with Down syndrome with nontraumatic habitual hip dislocation. Her hip joint was associated with acetabular dysplasia and hypoplasia of the posterior acetabular wall. Although conservative therapy was initially performed, no effects were observed. Rotational acetabular osteotomy and capsular plication were performed to reconstruct the posterior acetabular wall. No postoperative redislocation occurred, and the treatment effects were favorably sustained for 2 years. In Down syndrome, few cases of developmental dysplasia and hypoplasia of the posterior acetabular wall have been reported. In previous reports, these morphological abnormalities were rarely taken into consideration when determining the treatment strategy, and to our knowledge, no other reports demonstrate therapy involving rotational acetabular osteotomy for hip dislocation complicated with Down syndrome. Whether the acetabulum had posterior wall deficiency was thought to be important for conservative and surgical therapies in hip dislocation in patients with Down syndrome. Rotational acetabular osteotomy could be an effective surgical procedure for reconstruction of the acetabulum by posterolateral rotation of the osteotomized acetabulum.

Selective laminoplasty after the preoperative diagnosis of the responsible level using spinal cord evoked potentials in elderly patients with cervical spondylotic myelopathy: a preliminary report.

Study Design A preliminary report of a new operative method termed selective laminoplasty after the preoperative diagnosis of the responsible level using spinal cord evoked potentials (SCEPs) in elderly patients with cervical spondylotic myelopathy. Objective To introduce the method and clinical results for selective laminoplasty. Summary of Background Data Clinical results for conventional laminoplasty and anterior decompression and fusion guided by SCEPs have been reported. However, there have been no reports that consider SCEP results for selecting the optimal level in lamioplasty for cervical spondylotic myelopathy. Methods Seven elderly patients who underwent selective laminoplasty were followed for a minimum of 12 months. The T2-high–intensity area on magnetic resonance imaging, the responsible level detected by SCEPs, and the laminoplasty level were recorded. The operative time, intraoperative bleeding, clinical results including the Japanese Orthopaedic Association score, recovery rate, Nurick grading scale, and visual analog scale of axial pain were investigated preoperatively and postoperatively. Results The responsible intervertebral levels were at C3-C4 in 3 patients and at C4-C5 in 4 patients. These were identical for SCEP recorded after median nerve stimulation and transcranial electric stimulation. High-intensity area on T2-weighted magnetic resonance imaging was seen in 6 patients (3 at C3-C4 and 3 at C4-C5). The average operative time was 106 minutes and the average amount of bleeding was 20 mL. Neurologic recovery was achieved in all patients except 1 who had severe myelopathy. Visual analog scales of axial pain were 41.3±33.9 before surgery and 18.0±19.4 at final follow-up. The Japanese Orthopaedic Association score and the Nurick grade improved in 6 patients but did not change in 1 patient. Conclusions Preliminary clinical results for selective laminoplasty were satisfactory in all but 1 case. Although long-term results are not yet available, we consider this method to be less invasive and capable of giving satisfactory clinical results and benefits for elderly patients.

Transplantation of neurospheres derived from bone marrow stromal cells promotes neurological recovery in rats with spinal cord injury

Previous studies have revealed that cell therapy using bone marrow stromal cells (BMSCs) could promote motor functional recovery in animals with spinal cord injury (SCI). We describe here the development of cell biology technique and the experimental study of regeneration in SCI. The aim of this study was to investigate the potential for neurological recovery by transplantation neurospheres (NS) derived from BMSCs into thoracic SCI. Adult Fisher rats were used: 45 were subjected to complete thoracic SCI performed by the balloon compression method. BMSCs were cultured in vitro to obtain NS. Seven days after thoracic SCI, groups of 15 rats each received transplants of BMSCs-NS (group A), BMSCs (group B), or injection of medium only (group C) into the SCI lesion. Rats from each group were evaluated and compared longitudinally for motor function recovery. The spinal cords (SC) of injured rats were harvested at day 21 or day 42 and prepared for histological analysis. Five weeks after transplantation, many neuronal or axonal sproutings were observed and replaced by host cells in the SCI lesion of group A. Also, transplanted BMSCs-NS expressed neuronal lineage markers. Transplanted rats could walk with weight bearing and showed recovered motor evoked potentials (MEPs).

Postpartum pyogenic sacroiliitis with methicillin-resistant Staphylococcus aureus in a healthy adult: A case report and review of the literature

OBJECTIVE Back and buttock pain during pregnancy and the postpartum period generally improves spontaneously and rarely causes problems. However, such pain is infrequently induced by pyogenic sacroiliitis. CASE REPORT We herein present a 37-year-old female patient with no previous medical history who developed pyogenic sacroiliitis with severe right buttock pain 7 days after cesarean delivery. Arthrocentesis was performed, and a culture revealed the presence of methicillin-resistant Staphylococcus aureus (MRSA). After 6 weeks of treatment with intravenous antibiotics, her infection became quiescent. Eight cases of pyogenic sacroiliitis during the postpartum period and seven cases during pregnancy have been reported, but most of the causative pathogens were methicillin-sensitive Staphylococcus or Streptococcus species. CONCLUSION This report describes the first case of postpartum pyogenic sacroiliitis caused by MRSA. The frequency of infection with MRSA has recently increased, and community-acquired MRSA, which affects even healthy young people, has also become a problem. Antibiotics for empirical therapy after a diagnosis of pyogenic sacroiliitis, including anti-MRSA antibiotics, should be carefully selected.

Risk Factors Associated With Short-term Clinical Results After Total Hip Arthroplasty for Patients With Rheumatoid Arthritis

Clinical outcomes of total hip arthroplasty for rheumatoid arthritis are reportedly worse than those of total hip arthroplasty for osteoarthritis of the hip. The authors examined pre- and postoperative factors associated with the modified Harris hip score (mHHS). Fifty-one joints of 48 rheumatoid arthritis patients who underwent total hip arthroplasty were studied retrospectively. The authors examined the correlation between preoperative rheumatoid arthritis disease activity (Disease Activity Score in 28 joints-C-reactive protein and C-reactive protein) and mHHS at 1 year after total hip arthroplasty. Furthermore, pre- and postoperative mHHS values were compared between patients with other affected joints and patients with no affected joints in the lower limbs. The mean mHHS improved to 73.5 points postoperatively from 36.4 points preoperatively. Preoperative Disease Activity Score in 28 joints-C-reactive protein and C-reactive protein values were negatively correlated with pre- and postoperative mHHS values. Preoperative mHHS was not significantly different between the affected and not affected groups; however, postoperative mHHS was significantly lower in the affected group than in the not affected group. Total hip arthroplasty showed good clinical results for rheumatoid arthritis at short-term follow-up. However, pre- and postoperative mHHS values were influenced by preoperative rheumatoid arthritis disease activity. Moreover, the presence of additional affected joints in the lower limbs preoperatively resulted in a lower postoperative mHHS. Unlike patients with osteoarthritis, patients with rheumatoid arthritis often have multiple affected joints, which may contribute to a lower mHHS. Comprehensive treatment, including surgery for the other affected joints in the lower limbs, may improve a patients postoperative mHHS. [Orthopedics. 2018; 41(6):e772-e776.].

Weight bearing joints destruction in rheumatoid arthritis.

In many cases of rheumatoid arthritis (RA) joints of the upper extremities are affected. However, involvement of weight bearing joints of the lower extremities is strongly associated with a decreased activities of daily living ability such as gait disorder. Once the progression of weight bearing joint destruction occurs, lower extremity function will decrease even if RA disease activity is improved by pharmacotherapy. In this article, we investigated joint destruction suppressing effects of pharmacotherapy on the hip and knee joints, as well as risk factors for joint destruction. We also discuss surgical treatment strategies and clinical outcomes for progressive joint destruction.

Morning Stiffness in Rheumatoid Arthritis: Investigating its Relationship with Disease Activity as Assessed by Power Doppler Ultrasonography and Composite Scores

Abstract Objective: This study investigated potential associations of morning stiffness (MS) with rheumatoid arthritis (RA) disease activity and ultrasonography (US). Methods: We conducted a cross-sectional analysis of 100 consecutive patients with RA divided into MS-positive group (n = 38) and MS-negative group (n = 62). US findings, disease activity score in 28 joints (DAS28) and Clinical Disease Activity Index (CDAI) were compared. Results: DAS28, CDAI and the number of power Doppler (PD) signal-positive joints were significantly higher in the MS-positive group (p < 0.01). The number of patients who did not achieve the DAS28 or CDAI remission criteria was significantly higher in the MS-positive group (p < 0.01). When cut-off points were applied, MS duration of ≥10 min was associated with PD signal-positive joints, with a sensitivity of 47.5% and a specificity of 92.3% (area under curve = 0.7087, chi-square test: p < 0.0001). Conclusion: This study showed that in patients with MS duration of ≥10 min, there was a high probability of PD-positive joints in the hand.

AB0319 Is DAS28 a Useful Tool for Evaluating Hip Joint Disorders in Rheumatoid Arthritis

Background The 28-joint disease activity score (DAS28) is a particularly widely-used tool because it enables the physician to easily understand the state of RA. However, DAS28 assessment is primarily targeted to the joints of the upper extremity, being limited in the lower extremities to only the knee joints. Hip joints are weight bearing and their spherical shape tends to concentrate the load onto the weight-bearing area, where rapid joint distraction is often reported. Therefore, early diagnosis and treatment are essential. However, hip joints are located deep within the body, often making it difficult to obtain physical findings, such as swelling, thereby leading to delayed diagnosis. Objectives In our present study, we examined the relationship between the histological severity of synovitis in the hip joint and the DAS28 score. We also evaluated whether DAS28 is useful for hip joint assessment. Methods We studied 31 joints of 27 patients with rheumatoid arthritis of the hip who had undergone total hip arthroplasty. In all cases, the hip joint removed during the operation was histologically evaluable for synovitis. The subject population had a mean age of 66.3 years and mean disease duration of 13.4 years. As preoperative assessment, disease activity of RA was evaluated using DAS28 using C-reactive protein (DAS28-CRP) and CRP, and hip joint function was evaluated by the Japanese Orthopaedic Association (JOA) score for hip function. A perfect JOA score is 100 and the worst score is 0. In addition, the severity of synovitis was assessed employing the synovitis score for hematoxylin-eosin stained specimens as proposed by Krenn et al. and the correlations among individual parameters were tested for statistical significance. Results In the preoperative assessment, mean DAS28-CRP was 2.94±0.79, mean CRP was 1.85±0.36 mg/dL, and the mean JOA score was 39.0±13.1 points. The DAS28-CRP correlated negatively with the JOA score (r=-0.6188, P=0.0002). The mean synovitis score was 3.97±0.32 points, and correlated positively with both DAS28-CRP and CRP (r=0.4565, P=0.0098)(r=0.4509, P=0.0109). Furthermore, the synovitis score did not correlate with the JOA score. Conclusions We found significant negative correlations between preoperative DAS28 and JOA score in RA patients. The result suggests that DAS28 without hip joint assessment can indirectly represent the status of hip joints. In addition, the histological severity of synovitis in the hip joint showed positive correlations with both DAS28-CRP and CRP, supporting the usefulness of DAS28 as an indirect assessment tool for hip joints. In patients with highly active disease, physical findings may not be significant, but screening employing not only X-rays but also ultrasonography and magnetic resonance imaging, focusing on potential hip joint disorders, is anticipated to contribute to early diagnosis and prevention of hip joint destruction. References Krenn V et al. Synovitis score: discrimination between chronic low-grade and high-grade synovitis. Histopathology 49;358-64,2006 Disclosure of Interest None declared