Search

Analgesic discoblock is widely used for the diagnosis or treatment of discogenic low back pain by injecting local anesthetics. The purpose of this study was to investigate the deleterious effects of local anesthetics on degenerated rabbit intervertebral disks (IVDs) using an organotypic culture model and in vivo long-term follow-up model. To induce IVD degeneration, a rabbit annular puncture model was used. For the organotypic culture model, degenerated IVDs were harvested 1 month after the initial annular puncture and cultured for 3 or 7 days after intradiscal injection of local anesthetics (1% lidocaine and 0.5% bupivacaine). To perform in vivo analysis, local anesthetics were injected into degenerated IVDs, and IVDs were prepared for histological analysis after 6 or 12 months. In the organotypic model, terminal deoxynucleotidyl transferase dUTP nick end labeling-positive nucleus pulposus (NP) cells were significantly increased in the bupivacaine group compared with the other groups. In the in vivo study, the number of NP cells was significantly decreased in the saline and local anesthetics groups compared with the untreated control and puncture-only groups. However, there was no significant difference among the saline, lidocaine, and bupivacaine groups. In addition, histological analysis showed no significant difference of IVD degeneration among the puncture-only, saline, lidocaine, and bupivacaine groups. Although bupivacaine induced apoptotic NP cell death in the organotypic culture model, in vivo observations did not show any definitive proof to suggest that local anesthetics were capable of promoting degeneration in the degenerated IVD, except for pressurized injection-induced damage. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1963-1971, 2019., (© 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.)

In this study, we investigated antioxidant activity of proteins from the red alga dulse (Palmaria sp.) harvested in Hokkaido, Japan. The dulse proteins that contain phycoerythrin (PE) as the main component showed a high radical scavenging activity. To clarify the key constituent of antioxidant activity in dulse proteins, we prepared recombinant dulse PE β-subunit (rPEβ) (apoprotein) and chromophores from the dulse proteins. As a result, the rPEβ showed lower radical scavenging activity than that of dulse proteins. On the other hand, the dulse chromophores composed mainly of phycoerythrobilin (PEB) indicated extremely higher radical scavenging activity (90.4% ± 0.1%) than that of dulse proteins (17.9% ± 0.1%) on ABTS assay. In addition, on cell viability assay using human neuroblastoma SH-SY5Y cells, the dulse chromophores showed extracellular and intracellular cytoprotective effects against H 2 O 2 -induced cell damage. From these data, we concluded that the dulse proteins have antioxidant ability and the activity principally derives from the chromophores. PRACTICAL APPLICATION: Dulse is an abundant and underused resource, which contains a lot of proteins, especially phycoerythrin. We here demonstrated that the practically prepared dulse proteins possessed antioxidant activity and clarified that chromophores from the dulse proteins were the key components. Therefore, the dulse proteins have a potential for functional material., (© 2018 Wiley Periodicals, Inc.)

Creutzfeldt-Jakob disease (CJD) is characterized by rapidly progressive dementia with a variety of neurological disorders and a fatal outcome. The authors present a case with visual disturbance as a leading symptom and rapid deterioration in global cognitive functions. The cerebrospinal fluid was positive for 14-3-3 protein, and diffusion-weighted magnetic resonance imaging (MRI) showed marked hyperintensity in the parieto-occipital cortices, where hypometabolism was clearly detected on positron emission tomography (PET). Pattern-reversal visual evoked potentials showed prolonged P100 latencies and increased N/5/P100 amplitudes. All these findings supported a diagnosis of the Heidenhain variant of CJD, whereas a long clinical course, a lack of myoclonus, and an absence of periodic synchronous discharges on electroencephalography were atypical. Diffusion-weighted MRI and PE1 in combination with visual evoked potential recording and 14-3-3 protein detection may be useful for the early diagnosis of CJD.