An antibacterial coated polymer prevents biofilm formation and implant-associated infection.

To prevent infections associated with medical implants, various antimicrobial silver-coated implant materials have been developed. However, these materials do not always provide consistent antibacterial effects in vivo despite having dramatic antibacterial effects in vitro, probably because the antibacterial effects involve silver-ion-mediated reactive oxygen species generation. Additionally, the silver application process often requires extremely high temperatures, which damage non-metal implant materials. We recently developed a bacteria-resistant coating consisting of hydroxyapatite film on which ionic silver is immobilized via inositol hexaphosphate chelation, using a series of immersion and drying steps performed at low heat. Here we applied this coating to a polymer, polyetheretherketone (PEEK), and analyzed the properties and antibacterial activity of the coated polymer in vitro and in vivo. The ionic silver coating demonstrated significant bactericidal activity and prevented bacterial biofilm formation in vitro. Bio-imaging of a soft tissue infection mouse model in which a silver-coated PEEK plate was implanted revealed a dramatic absence of bacterial signals 10 days after inoculation. These animals also showed a strong reduction in histological features of infection, compared to the control animals. This innovative coating can be applied to complex structures for clinical use, and could prevent infections associated with a variety of plastic implants.

Effects of peripheral tears of the triangular fibrocartilage complex on distal radioulnar joint stability: A biomechanical study.

BACKGROUND: Peripheral triangular fibrocartilage complex (TFCC) tears may induce instability of the distal radioulnar joint (DRUJ). In this biomechanical study, simulated peripheral tears of the TFCC were examined on the stability of the DRUJ. Restabilization effect of the DRUJ by ulnar shortening and direct repair of those injuries were sequentially examined. METHOD: The DRUJ stiffness was measured in intact, simulated two types of peripheral tears (ulnar and extended ulnodorsal) at three forearm positions: neutral, 60° pronation and 60° supination in 8 fresh frozen cadaver specimens. After the tears were sutured with stitches or after simulated ulnar shortening of 3 mm, the DRUJ stiffness was again measured. RESULTS: The ulnar and ulnodorsal TFCC tears decreased the DRUJ stiffness significantly compared with the intact in all forearm positions. When ulnar shortening was done for the ulnar tear, the DRUJ stiffness increased significantly in the neutral and 60° pronated positions. When the ulnar TFCC tear was repaired, the DRUJ stiffness increased significantly in all forearm positions. DRUJ stiffness did not increase either with ulnar shortening or repair in ulnodorsal tear of the TFCC, however. CONCLUSION: The simulated TFCC tears indicated significant loss of DRUJ stiffness. Direct repair or ulnar shortening was effective only on treatment of the ulnar tear of the TFCC in this study.

Hypertrophic Pisiform: A Case of Osteoid Osteoma.

We treated an extremely rare case of osteoid osteoma of the pisiform. Pisiform hypertrophy caused persistent pain and ulnar nerve irritation at Guyon's canal after the initial trauma. The re-enlargement of the pisiform attracted our attention allowing us to ultimately diagnose the condition as osteoid osteoma and treat the patient with a successful clinical result.

Structural and functional identification of two distinct inspiratory neuronal populations at the level of the phrenic nucleus in the rat cervical spinal cord.

The diaphragm is driven by phrenic motoneurons that are located in the cervical spinal cord. Although the anatomical location of the phrenic nucleus and the function of phrenic motoneurons at a single cellular level have been extensively analyzed, the spatiotemporal dynamics of phrenic motoneuron group activity have not been fully elucidated. In the present study, we analyzed the functional and structural characteristics of respiratory neuron population in the cervical spinal cord at the level of the phrenic nucleus by voltage imaging, together with histological analysis of neuronal and astrocytic distribution in the cervical spinal cord. We found spatially distinct two cellular populations that exhibited synchronized inspiratory activity on the transversely cut plane at C4-C5 levels and on the ventral surface of the mid cervical spinal cord in the isolated brainstem-spinal cord preparation of the neonatal rat. Inspiratory activity of one group emerged in the central portion of the ventral horn that corresponded to the central motor column, and the other appeared in the medial portion of the ventral horn that corresponded to the medial motor column. We identified by retrogradely labeling study that the anatomical distributions of phrenic and scalene motoneurons coincided with optically detected central and medial motor regions, respectively. Furthermore, we anatomically demonstrated closely located features of putative motoneurons, interneurons and astrocytes in these regions. Collectively, we report that phrenic and scalene motoneuron populations show synchronized inspiratory activities with distinct anatomical locations in the mid cervical spinal cord.

Hyaluronan-Binding Protein Involved in Hyaluronan Depolymerization Is Up-Regulated and Involved in Hyaluronan Degradation in Human Osteoarthritic Cartilage.

Hyaluronan (HA)-binding protein involved in HA depolymerization (HYBID), also called cell migration-inducing protein (CEMIP; alias KIAA1199), plays a key role in the degradation of HA in skin and arthritic synovial fibroblasts, but its functions in osteoarthritic (OA) cartilage remain elusive. Here, we investigated the expression and roles of HYBID in human OA cartilage. HYBID was highly expressed by chondrocytes in the HA-depleted area of OA cartilage, and HYBID immunoreactivity was correlated with Mankin score, the histopathologic severity of OA lesions of cartilage. Real-time quantitative PCR indicated that HYBID expression was significantly higher in OA cartilage than in control cartilage. In addition, OA chondrocytes exhibited HA-degrading activity, which was abolished by knock-down of HYBID by siRNAs. Although OA chondrocytes also expressed certain levels of hyaluronidases 1 and 2 and CD44, knock-down of these molecules exhibited negligible effects on HA degradation. Double immunostaining of HYBID and clathrin heavy chain revealed that HYBID was localized in the clathrin-coated vesicles, and HA was endocytosed within the vesicles of OA chondrocytes. Among eight factors including cytokines and growth factors examined, only tumor necrosis factor α stimulated OA chondrocytes to overexpress HYBID. These data are the first to demonstrate that HYBID is up-regulated in OA cartilage, and suggest that tumor necrosis factor α-stimulated HYBID plays a role in HA degradation in OA cartilage.

The Amelioration of Pain-Related Behavior in Mice with Chronic Spinal Cord Injury Treated with Neural Stem/Progenitor Cell Transplantation Combined with Treadmill Training.

Progress in regenerative medicine is realizing the possibility of neural regeneration and functional recovery in spinal cord injury (SCI). Recently, rehabilitation has attracted much attention with respect to the synergistic promotion of functional recovery in combination with neural stem/progenitor cell (NS/PC) transplantation, even in the chronic refractory phase of SCI. Nevertheless, sensory disturbance is one of the most prominent sequelae, even though the effects of combination or single therapies have been investigated mostly in the context of motor recovery. To determine how combination therapy with treadmill training (TMT) and NS/PC transplantation affects the manifestation of thermal allodynia and tactile hyperalgesia in chronic phase SCI, four groups of SCI mice were used to assess pain-related behavior and histological changes: combined transplantation and TMT therapy, transplantation only, TMT only, and control groups. Thermal allodynia and coarse touch-pressure hyperalgesia exhibited significant recovery in the combined therapy group in comparison with controls, whereas there were no significant differences with fine touch-pressure hyperalgesia and motor function. Further investigation revealed fewer fibers remaining in the posterior funiculus, which contained the tracts associated with the two modalities showing less recovery; that is, touch-pressure hyperalgesia and motor function. A significant correlation was only observed between these two modalities. Although no remarkable histological recovery was found within the lesion epicenter, changes indicating amelioration of pain were observed in the lumbar enlargement of the combination therapy group. Our results suggest that amelioration of thermal allodynia and tactile hyperalgesia can be brought about by the additive effect of NS/PC transplantation and TMT. The degree of recovery seems dependent on the distribution of damage.

A multicenter, randomized, double-blind, dose-finding study of condoliase in patients with lumbar disc herniation.

OBJECTIVE Chemonucleolysis with condoliase has the potential to be a new, less invasive therapeutic option for patients with lumbar disc herniation (LDH). The aim of the present study was to determine the most suitable therapeutic dose of condoliase. METHODS Patients between 20 and 70 years of age with unilateral leg pain, positive findings on the straight leg raise test, and LDH were recruited. All eligible patients were randomly assigned to receive condoliase (1.25, 2.5, or 5 U) or placebo. The primary end point was a change in the worst leg pain from preadministration (baseline) to week 13. The secondary end points were changes from baseline in the following items: worst back pain, Oswestry Disability Index (ODI), SF-36, and neurological examination. For pharmacokinetic and pharmacodynamic analyses, plasma condoliase concentrations and serum keratan sulfate concentrations were measured. The safety end points were adverse events (AEs) and radiographic and MRI parameters. Data on leg pain, back pain, abnormal neurological findings, and imaging parameters were collected until week 52. RESULTS A total of 194 patients received an injection of condoliase or placebo. The mean change in worst leg pain from baseline to week 13 was -31.7 mm (placebo), -46.7 mm (1.25 U), -41.1 mm (2.5 U), and -47.6 mm (5 U). The differences were significant at week 13 in the 1.25-U group (-14.9 mm; 95% CI -28.4 to -1.4 mm; p = 0.03) and 5-U group (-15.9 mm; 95% CI -29.0 to -2.7 mm; p = 0.01) compared with the placebo group. The dose-response improvement in the worst leg pain at week 13 was not significant (p = 0.14). The decrease in the worst leg pain in all 3 condoliase groups was observed from week 1 through week 52. Regarding the other end points, the worst back pain and results of the straight leg raise test, ODI, and SF-36 showed a tendency for sustained improvement in each of the condoliase groups until week 52. In all patients at all time points, plasma condoliase concentrations were below the detectable limit (< 100 µU/ml). Serum keratan sulfate concentrations significantly increased from baseline to 6 hours and 6 weeks after administration in all 3 condoliase groups. No patient died or developed anaphylaxis or neurological sequelae. Five serious AEs occurred in 5 patients (3 patients in the condoliase groups and 2 patients in the placebo group), resolved, and were considered unrelated to the investigational drug. Severe AEs occurred in 10 patients in the condoliase groups and resolved or improved. In the condoliase groups, back pain was the most frequent AE. Modic type 1 change and decrease in disc height were frequent imaging findings. Dose-response relationships were observed for the incidence of adverse drug reactions and decrease in disc height. CONCLUSIONS Condoliase significantly improved clinical symptoms in patients with LDH and was well tolerated. While all 3 doses had similar efficacy, the incidence of adverse drug reactions and decrease in disc height were dose dependent, thereby suggesting that 1.25 U would be the recommended clinical dose of condoliase. Clinical trial registration no.: NCT00634946 (clinicaltrials.gov).

Condoliase for the Treatment of Lumbar Disc Herniation: A Randomized Controlled Trial.

STUDY DESIGN: A randomized, double-blind, placebo-controlled, multicenter phase III clinical trial. OBJECTIVE: To evaluate the efficacy and safety of chemonucleolysis with condoliase in patients with lumbar disc herniation (LDH). SUMMARY OF BACKGROUND DATA: Condoliase is a pure mucopolysaccharidase derived from a bacterium, Proteus vulgaris that has high substrate specificity for chondroitin sulfate and hyaluronic acid in the nucleus pulposus of the intervertebral disc. METHODS: In this study, patients aged 20 to 70 years with unilateral leg pain, positive straight leg raise test, and a contained LDH were recruited in Japan. Patients were treated with a single injection of condoliase (1.25 U) or placebo and were followed for 1 year after administration. The primary endpoint was change in worst leg pain from baseline to week 13. The secondary endpoints included responder rate, and the changes from baseline up to week 52 in the worst leg pain, worst back pain, Oswestry Disability Index, 36-Item Short-Form Health Survey, neurologic examinations, and imaging parameters. RESULTS: A total of 82 and 81 patients received an injection of condoliase and placebo, respectively. The average changes in worst leg pain from baseline to week 13 (primary endpoint) were -49.5 mm in the condoliase group and -34.3 mm in the placebo group, and the difference of -15.2 mm was significant (95% confidence interval, -24.2 to -6.2; P = 0.001). Significant improvements were observed in the condoliase groups, compared with the placebo group, in most secondary endpoints at 1 year after administration. In the condoliase group, back pain, Modic type 1 change, and decrease in disc height were frequently reported, without any clinically relevant consequences. CONCLUSION: Condoliase significantly improved symptoms in patients with LDH and was well tolerated. Condoliase is a novel and potent chemonucleolytic drug for the treatment of LDH. LEVEL OF EVIDENCE: 1.

Enpp1 is an anti-aging factor that regulates Klotho under phosphate overload conditions.

Control of phosphate metabolism is crucial to regulate aging in mammals. Klotho is a well-known anti-aging factor that regulates phosphate metabolism: mice mutant or deficient in Klotho exhibit phenotypes resembling human aging. Here we show that ectonucleotide pyrophosphatase/phosphodiesterase 1 (Enpp1) is required for Klotho expression under phosphate overload conditions. Loss-of-function Enpp1 ttw/ttw mice under phosphate overload conditions exhibited phenotypes resembling human aging and Klotho mutants, such as short life span, arteriosclerosis and osteoporosis, with elevated serum 1,25(OH)2D3 levels. Enpp1 ttw/ttw mice also exhibited significantly reduced renal Klotho expression under phosphate overload conditions, and aging phenotypes in these mice were rescued by Klotho overexpression, a low vitamin D diet or vitamin D receptor knockout. These findings indicate that Enpp1 plays a crucial role in regulating aging via Klotho expression under phosphate overload conditions.

Metastasis of Renal Cell Carcinoma to the Trapezium.

Solitary metastasis of a carcinoma to carpal bone is extremely rare. Metastases of renal cell carcinoma (RCC) usually occur in a multiple fashion and there has been no report to date of a solitary metastasis to trapezium from RCC. The tumor was excised and reconstructed with iliac bone transplantation. 2 years and 6 months after surgery, there is no local recurrence with minimal functional loss.

Scoliosis is a Risk Factor for Gastroesophageal Reflux Disease in Adult Spinal Deformity.

STUDY DESIGN: A prospective observational study. OBJECTIVE: To evaluate whether scoliosis is a risk factor for gastroesophageal reflux disease (GERD) in elderly patients. SUMMARY OF BACKGROUND DATA: Sagittal spinal deformities are reported to cause GERD, but its association with spinal deformity in the coronal plane is not well studied. METHODS: We examined 190 patients with spinal disorders (mean age 70.6±8.6 y) who underwent standing whole-spine x-rays in the coronal and sagittal planes. GERD symptoms were assessed by Quest score, with a cutoff of 6 points. The relationship between GERD symptoms and radiographic parameters was evaluated. Right convex coronal curves were given negative values, and left convex curves positive values. Degenerative scoliosis was defined when the thoracolumbar/lumbar Cobb angle had an absolute value >10 degrees. Risk factors for GERD were evaluated with univariate and multivariate logistic regression analyses. RESULTS: Of the patients, 126 had degenerative scoliosis at the thoracolumbar/lumbar spine (42 with right and 84 with left convex curve), and 59 had GERD. Multivariate logistic regression analysis revealed that the lumbar Cobb angle was significantly associated with GERD (P<0.05, odds ratio=1.021). When patients were categorized by Cobb angle of the lumbar curve (<-30 degrees, large right convex curve; -30 to +30 degrees, small curve; or >+30 degrees, large left convex curve), a large left convex curve was strongly associated with GERD (P<0.05, odds ratio=10.925). CONCLUSIONS: Left thoracolumbar/lumbar curve was a significant risk factor for GERD, and risk increased with a curve >30 degrees. Organ disorders such as GERD should be considered when treating elderly patients with degenerative scoliosis.

A missense single nucleotide polymorphism in the ALDH2 gene, rs671, is associated with hip fracture.

Hip fracture is the most severe bone fragility fracture among osteoporotic injuries. Family history is a known risk factor for fracture and now included among criteria for osteoporosis diagnosis and treatment; however, genetic factors underlying family history favoring fracture remain to be elucidated. Here we demonstrate that a missense SNP in the ALDH2 gene, rs671 (ALDH2*2), is significantly associated with hip fracture (odds ratio = 2.48, 95% confidence interval: 1.20-5.10, p = 0.021). The rs671 SNP was also significantly associated with osteoporosis development (odds ratio = 2.04, 95% confidence interval: 1.07-3.88, p = 0.040). For analysis we enrolled 92 hip fracture patients plus 48 control subjects without bone fragility fractures with higher than -2.5 SD bone mineral density. We also recruited 156 osteoporosis patients diagnosed as below -2.5 SD in terms of bone mineral density but without hip fracture. Association of rs671 with hip fracture and osteoporosis was significant even after adjustment for age and body mass index. Our results provide new insight into the pathogenesis of hip fracture.

Whole-Genome DNA Methylation Analyses Revealed Epigenetic Instability in Tumorigenic Human iPS Cell-Derived Neural Stem/Progenitor Cells.

Although human induced pluripotent stem cell (hiPSC) derivatives are considered promising cellular resources for regenerative medicine, their tumorigenicity potentially limits their clinical application in hiPSC technologies. We previously demonstrated that oncogenic hiPSC-derived neural stem/progenitor cells (hiPSC-NS/PCs) produced tumor-like tissues that were distinct from teratomas. To gain insight into the mechanisms underlying the regulation of tumorigenicity in hiPSC-NS/PCs, we performed an integrated analysis using the Infinium HumanMethylation450 BeadChip array and the HumanHT-12 v4.0 Expression BeadChip array to compare the comprehensive DNA methylation and gene expression profiles of tumorigenic hiPSC-NS/PCs (253G1-NS/PCs) and non-tumorigenic cells (201B7-NS/PCs). Although the DNA methylation profiles of 253G1-hiPSCs and 201B7-hiPSCs were similar regardless of passage number, the methylation status of the global DNA methylation profiles of 253G1-NS/PCs and 201B7-NS/PCs differed; the genomic regions surrounding the transcriptional start site of the CAT and PSMD5 genes were hypermethylated in 253G1-NS/PCs but not in 201B7-NS/PCs. Interestingly, the aberrant DNA methylation profile was more pronounced in 253G1-NS/PCs that had been passaged more than 15 times. In addition, we identified aberrations in DNA methylation at the RBP1 gene locus; the DNA methylation frequency in RBP1 changed as 253G1-NS/PCs were sequentially passaged. These results indicate that different NS/PC clones have different DNA methylomes and that DNA methylation patterns are unstable as cells are passaged. Therefore, DNA methylation profiles should be included in the criteria used to evaluate the tumorigenicity of hiPSC-NS/PCs in the clinical setting. Stem Cells 2017;35:1316-1327.

Evaluation of the immunogenicity of human iPS cell-derived neural stem/progenitor cells in vitro.

To achieve the goal of a first-in-human trial for human induced pluripotent stem cell (hiPSC)-based transplantation for the treatment of various diseases, allogeneic human leukocyte antigen (HLA)-matched hiPSC cell banks represent a realistic tool from the perspective of quality control and cost performance. Furthermore, considering the limited therapeutic time-window for acute injuries, including neurotraumatic injuries, an iPS cell bank is of potential interest. However, due to the relatively immunoprivileged environment of the central nervous system, it is unclear whether HLA matching is required in hiPSC-derived neural stem/progenitor cell (hiPSC-NS/PC) transplantation for the treatment of neurodegenerative diseases and neurotraumatic injuries. In this study, we evaluated the significance of HLA matching in hiPSC-NS/PC transplantation by performing modified mixed lymphocyte reaction (MLR) assays with hiPSC-NS/PCs. Compared to fetus-derived NS/PCs, the expression levels of human leukocyte antigen-antigen D related (HLA-DR) and co-stimulatory molecules on hiPSC-NS/PCs were significantly low, even with the addition of tumor necrosis factor-α (TNFα) and/or interferon-γ (IFNγ) to mimic the inflammatory environment surrounding transplanted hiPSC-NS/PCs in injured tissues. Interestingly, both the allogeneic HLA-matched and the HLA-mismatched responses were similarly low in the modified MLR assay. Furthermore, the autologous response was also similar to the allogeneic response. hiPSC-NS/PCs suppressed the proliferative responses of allogeneic HLA-mismatched peripheral blood mononuclear cells (PBMCs) in a dose-dependent manner. Thus, the low antigen-presenting function and immunosuppressive effects of hiPSC-NS/PCs result in a depressed immune response, even in an allogeneic HLA-mismatched setting. It is crucial to verify whether these in vitro results are reproducible in a clinical setting.

A serum metabolomics-based profile in low bone mineral density postmenopausal women.

Osteoporosis is characterized as a metabolic disorder of bone tissue, and various metabolic markers are now available to support its diagnosis and evaluate treatment effects. Substances produced as end products of metabolomic activities are the correlated factors to the biological or metabolic status, and thus, metabolites are considered highly sensitive markers of particular pathological states, including osteoporosis. Here we undertook comprehensive serum metabolomics analysis in postmenopausal women with or without low bone mineral density (low BMD vs controls) for the first time using capillary electrophoresis/mass spectrometry. Among the metabolites tested, 57 were detected in sera. Levels of hydroxyproline, Gly-Gly and cystine, differed significantly between groups, with Gly-Gly and cystine significantly lower in the low BMD group and hydroxyproline, a reported marker of osteoporosis, significantly higher. Levels of TRACP5b, a bone resorption marker, were significantly higher in the low BMD group, supporting the study's validity. Taken together, our findings represent novel metabolomic profiling in low BMD in postmenopausal women.

Selective Estrogen Receptor Modulators Suppress Hif1α Protein Accumulation in Mouse Osteoclasts.

Anti-bone resorptive drugs such as bisphosphonates, the anti-RANKL antibody (denosumab), or selective estrogen receptor modulators (SERMs) have been developed to treat osteoporosis. Mechanisms underlying activity of bisphosphonates or denosumab in this context are understood, while it is less clear how SERMs like tamoxifen, raloxifene, or bazedoxifene inhibit bone resorption. Recently, accumulation of hypoxia inducible factor 1 alpha (Hif1α) in osteoclasts was shown to be suppressed by estrogen in normal cells. In addition, osteoclast activation and decreased bone mass seen in estrogen-deficient conditions was found to require Hif1α. Here, we used western blot analysis of cultured osteoclast precursor cells to show that tamoxifen, raloxifene, or bazedoxifene all suppress Hif1α protein accumulation. The effects of each SERM on osteoclast differentiation differed in vitro. Our results suggest that interventions such as the SERMs evaluated here could be useful to inhibit Hif1α and osteoclast activity under estrogen-deficient conditions.