Nobuto Kitamura | Hokkaido University (original) (raw)

Papers by Nobuto Kitamura

Journal of Biomedical Materials Research Part A

International orthopaedics, Jan 15, 2018

To compare post-operative pain relief with peri-articular injection (PI) versus interscalene brac... more To compare post-operative pain relief with peri-articular injection (PI) versus interscalene brachial plexus block (IBPB) after arthroscopic rotator cuff repair (ARCR) surgery. We retrospectively reviewed 121 consecutive patients undergoing ARCR surgery divided into two groups: the PI group and the IBPB group. We compared complications and self-reported pain score measured using a Numerical Rating Scale (NRS) during the initial 24 hours after surgery. The NRS scores recorded in the recovery room (0), 0.5, and four hours post-operatively were higher in the PI group (n = 38) than the IBPB group (n = 52) (2.1 vs. 0.8, p = 0.014; 1.4 vs. 0.5, p = 0.0069; and 1.3 vs. 0.5, p = 0.012, respectively). However, the NRS scores recorded at 16, 20, and 24 hours post-operatively were lower in the PI group than in the IBPB group (1.4 vs. 3.1, p < 0.0001; 1.4 vs. 3.2, p < 0.0001; and 1.7 vs. 3.2, p = 0.00046, respectively). The incidences of post-operative nausea and temporary numbness in the...

The Proceedings of the Bioengineering Conference Annual Meeting of BED/JSME

$Research paper thumbnail of Talar head fracture in a professional baseball player: A case report$

Journal of Orthopaedic Science

Biomaterials, 2017

Soft supporting tissues in the human body, such as cartilages and ligaments, are tough materials ... more Soft supporting tissues in the human body, such as cartilages and ligaments, are tough materials and firmly fixed to bones. These soft tissues, once injured, cannot regenerate spontaneously in vivo. Developing tough and biocompatible hydrogels as artificial soft supporting tissues would substantially improve outcomes after soft tissue injury. Collagen is the main rigid component in soft connective tissues which is organized in various hierarchical arrays. We have successfully developed a novel class of collagen fibril-based tough hydrogels based on the double network (DN) concept using swim bladder collagen (SBC) extracted from Bester sturgeon fish. The DN hydrogels, SBC/PDMAAm, are composed of physically/chemically crosslinked anisotropic SBC fibril as the first network and neutral, biocompatible poly(N,N'-dimethylacrylamide) (PDMAAm) as the second network. The anisotropic structure of SBC fibril network, which is well retained in the DN hydrogels, is formed by free injection m...

Asia-Pacific Journal of Sports Medicine, Arthroscopy, Rehabilitation and Technology, 2016

There is controversy regarding the efficacy of remnant tissue preservation on graft healing in an... more There is controversy regarding the efficacy of remnant tissue preservation on graft healing in anterior cruciate ligament (ACL) reconstruction. The preserved remnant tissue will (1) adhere to the graft surface and undergo a remodeling process, (2) accelerate graft revascularization, (3) increase the number of graft mechanoreceptors by 4 weeks, and (4) improve anteroposterior knee laxity and structural properties of the graft by 12 weeks. Controlled laboratory study. Forty-two sheep were randomly divided into 2 groups of 21 animals. In group I, the ACL was completely removed. In group II, the ACL was transected at the midsubstance but not debrided. ACL reconstruction was performed using a semitendinosus tendon autograft in both groups. Histological changes of the grafted tendon and the remnant tissue were evaluated at 4 and 12 weeks after surgery. Biomechanically, anterior translation and knee joint stiffness under an anterior drawer force and the structural properties of the femur-graft-tibia complex were evaluated. The preserved remnant tissue was histologically distinct from the graft at 4 weeks, while the tissue partially adhered to the graft surface at 12 weeks. The ACL remnant tissue significantly accelerated revascularization in the grafted tendon at 4 weeks and significantly increased the number of mechanoreceptors at 4 and 12 weeks. In addition, remnant preservation significantly improved anterior translation (9.3 ± 2.1 mm and 5.4 ± 1.7 mm at 60° of knee flexion in groups I and II, respectively) and knee joint stiffness at 12 weeks. However, there were no significant differences in the structural properties between the 2 groups at 4 and 12 weeks after surgery. Preservation of the ACL remnant tissue in ACL reconstruction enhanced cell proliferation, revascularization, and regeneration of proprioceptive organs in the reconstructed ACL and reduced anterior translation. However, remnant preservation did not improve the structural properties of the graft. These results imply that preservation of the ACL remnant tissue may improve graft healing after ACL reconstruction.

Jahrbuch Fur Morphologie Und Mikroskopische Anatomie 2 Abteilung Zeitschrift Fur Mikroskopisch Anatomische Forschung, 1989

Molecular Imaging for Integrated Medical Therapy and Drug Development, 2010

ABSTRACT

Journal of biomedical materials research. Part A, Sep 18, 2016

The purpose of this study was to establish the efficacy of a therapeutic strategy for an articula... more The purpose of this study was to establish the efficacy of a therapeutic strategy for an articular cartilage defect using a PAMPS/PDMAAm DN gel in a sheep model. Seventeen mature sheep were used in this study. We created a 6.0-mm osteochondral defect in the femoral trochlea of the patellofemoral (PF) joint and the medial condyle of the tibiofemoral (TF) joint. A cylindrical DN gel plug was implanted into the defect of the right knee so that a vacant space of the planned depths of 2.0 mm in Group I, 3.0 mm in Group II, and 4.0 mm in Group III were left. In the left knee, we created a defect with the same depth as the right knee. The regenerated tissues were evaluated with the O'Driscoll score and real time PCR analysis of the cartilage marker genes at 12 weeks. The DN-gel implanted defect of Group II in the PF and TF joints was completely filled with a sufficient volume of the proteoglycan-rich tissue stained with Safranin-O. The score showed that Group II was significantly great...

The American journal of sports medicine, Jan 27, 2016

Advanced materials (Deerfield Beach, Fla.), Jan 17, 2016

Implanting hydroxyapatite-mineralized tough hydrogel into osteochondral defects of rabbits, osteo... more Implanting hydroxyapatite-mineralized tough hydrogel into osteochondral defects of rabbits, osteogenesis spontaneously penetrates into the gel matrix owing to the semi-permeablility of the hydrogel. The gradient layer (around 40 μm thick) contributes quite strong bonding of the gel to bone. This is the first success in realizing the robust osteointegration of tough hydrogels, and the method is simple and feasible for practical use.

Jahrbuch Fur Morphologie Und Mikroskopische Anatomie 1 Abteilung Gegenbaurs Morphologisches Jahrbuch, 1987

The Journal of bone and joint surgery. American volume, Jan 18, 2015

Arthroscopic osseous Bankart repair for shoulders with chronic recurrent anterior instability has... more Arthroscopic osseous Bankart repair for shoulders with chronic recurrent anterior instability has been reported as an effective procedure with promising short-term outcomes. However, to date, we know of no report describing longer-term outcomes and glenoid morphologic change. The purpose of the present study was to report intermediate to long-term outcomes and glenoid morphologic change after arthroscopic osseous Bankart repair in patients with substantial glenoid bone loss. A consecutive series of eighty-five patients with traumatic anterior glenohumeral instability associated with a chronic osseous Bankart lesion underwent arthroscopic repair from January 2005 through December 2006. Forty-six patients with bone loss of >15% of the inferior glenoid diameter relative to the assumed inferior circle regardless of the fragment size were selected as candidates for this study. Thirty-eight patients (83%), including thirty-four male and four female patients, with a mean age of 23.4 yea...

Journal of biomedical materials research. Part A, Jan 14, 2015

The purposes of this study were to identify signaling pathways that were specifically activated i... more The purposes of this study were to identify signaling pathways that were specifically activated in ATDC5 cells cultured on poly (2-acrylamido-2-methylpropanesulfonic acid) (PAMPS) gel in insulin-free maintenance medium and to evaluate the significance of the determined signaling pathways in the chondrogenic differentiation induced by this gel. In this study, ATDC5 cells cultured on PAMPS gel using the maintenance medium without insulin (PAMPS Culture) were compared with cells cultured on polystyrene using the differentiation medium containing insulin (PS-I Culture). The microarray analysis, Western blot analysis, and real-time PCR analysis demonstrated that the TGF-β/BMP signaling pathway was significantly enhanced at Days 1, 2, and 3 in the PAMPS Culture when compared with the PS-I Culture. Inhibition of the BMP type-I receptor reduced the phosphorylation level of Smad1/5 and expression of type-2 collagen and aggrecan mRNA in the cells accompanied by a reduction in cell aggregation...

Orthopaedic journal of sports medicine

Tunnel enlargement and coalition following double-bundle anterior cruciate ligament (ACL) reconst... more Tunnel enlargement and coalition following double-bundle anterior cruciate ligament (ACL) reconstruction with hamstring tendon autografts has not yet been sufficiently studied. The incidence and the degree of femoral tunnel enlargement will be significantly greater than those for tibial tunnel enlargement after anatomic double-bundle ACL reconstruction using hamstring tendon autografts. There will be no significant correlation between tunnel enlargement and coalition and the postoperative knee laxity. Case series; Level of evidence, 4. Thirty-nine patients who underwent anatomic double-bundle ACL reconstruction using semitendinosus and gracilis tendon autografts were followed up for 1 year after surgery. The grafts were simultaneously fixed at 10° of knee flexion with EndoButtons and spiked staples. All patients were examined with computed tomography and the standard clinical evaluation methods at 2 weeks and 1 year after surgery. The degree of tunnel enlargement of the femoral ante...

The American journal of sports medicine, Jan 11, 2015

Clinical utility of remnant tissue preservation after single-bundle anterior cruciate ligament (A... more Clinical utility of remnant tissue preservation after single-bundle anterior cruciate ligament (ACL) reconstruction has not been established. In addition, no studies have evaluated the clinical utility of remnant preservation after anatomic double-bundle ACL reconstruction. The study hypotheses were as follows: (1) Subjective and functional clinical results may be comparable between anatomic double-bundle reconstructions that preserve the remnant tissue and those that resect the remnant tissue, (2) postoperative knee stability and the second-look arthroscopic evaluation may be significantly more favorable with the remnant-preserving reconstruction, and (3) the degree of the initial graft coverage may significantly affect postoperative knee stability. Cohort study; Level of evidence, 2. A total of 179 patients underwent anatomic double-bundle ACL reconstruction. Based on the Crain classification of ACL remnant tissue, 81 patients underwent the remnant-preserving procedure (group P) a...

Journal of orthopaedic science : official journal of the Japanese Orthopaedic Association, 2014

The purpose of this study was to clarify the biomechanical characteristics of cement-material int... more The purpose of this study was to clarify the biomechanical characteristics of cement-material interfaces for the zirconia ceramic and cobalt-chromium (Co-Cr) alloy femoral components used for total knee arthroplasty. In the first sub-study, we compared the strength of adhesion of the cement to flat plates, by tensile testing under dry and moistened conditions. In the second sub-study, we compared the maximum load of the cement-component complex by tensile testing. In the third sub-study, we compared the fatigue characteristics of the cement-component complex by use of a dynamic tensile testing machine. Under dry conditions, the maximum strength of adhesion to the zirconia ceramic plate was the same as that to the Co-Cr alloy plate. Under moistened conditions, however, the strength of adhesion to the zirconia ceramic plate was significantly lower (p = 0.0017) whereas the strength of adhesion to the Co-Cr alloy plate was not reduced. Maximum load for the cement-component complexes for...

International journal of molecular medicine, 2004

Manganese superoxide dismutase (Mn-SOD) is a key antioxidant enzyme that prevents reactive oxygen... more Manganese superoxide dismutase (Mn-SOD) is a key antioxidant enzyme that prevents reactive oxygen species (ROS) damage to biological tissues. Although Mn-SOD has been investigated for a variety of cells, little is known about its expression in the tendon, particularly in the stress-deprived condition. The present study demonstrated that Mn-SOD is excessively expressed in the cultured fibroblasts derived from the stress-deprived patellar tendon in the rat using subtractive hybridization analysis. In addition, we confirmed that the expression of Mn-SOD is up-regulated in the stress-deprived patellar tendon in vivo at both the mRNA and protein levels. These results suggest that Mn-SOD may play a role in regulating ROS and matrix degradation involving mechanical deterioration of the stress-deprived tendon tissue.