Epidemiologic analysis of the clinical features of Japanese patients with polymyositis and dermatomyositis

Objectives: This study aimed to investigate the clinical characteristics of polymyositis/dermatomyositis (PM/DM) in Japan by analyzing data from the nationwide registration system.

Methods: The data of the registration system in 2009 were analyzed to investigate patient numbers, sex, clinical symptoms, therapies, complications, and prognosis of PM/DM.

Results: The total number of PM/DM cases was approximately 17,000, and the female/male sex ratio was 2.7:1. Almost all patients improved as a result of therapy, but many suffered from sequelae such as muscle weakness.

Conclusions: The results characterize significant aspects of Japanese PM/DM patients. However, a further prospective survey is required to clarify the true epidemiology and natural history of PM/DM.     

Tidal volume and diaphragm muscle activity in rats with cervical spinal cord injury

[Purpose] The purpose of this study was to make an experimental model of cervical spinal cord injury (CSCI) using Wistar rats, in order to analyze the influence of CSCI on the respiratory function. [Subjects] Thirty-two male 12-week-old Wistar rats were used. [Methods] The CSCI was made at the levels from C3 to C7, and we performed pneumotachography and electromyography (EMG) on the diaphragm. Computed tomography was used to determine the level of spinal cord damage. [Results] After the operation, the tidal volume of the rats with a C3 level injury decreased to approximately 22.3% of its pre-injury value. In addition, in the same rats, the diaphragmatic electromyogram activity decreased remarkably. Compared with before CSCI, the tidal volume decreased to 78.6% of its pre-injury value in CSCI at the C5 level, and it decreased to 94.1% of its pre-injury value in CSCI at the C7 level. [Conclusion] In the rats that sustained a CSCI in this study, the group of respiratory muscles that receive innervation from the thoracic spinal cord was paralyzed. Therefore, the EMG signal of the diaphragm increased. These results demonstrate that there is a relationship between respiratory function and the level of CSCI.Key words: Cervical spinal cord injury, Respiratory function, Electromyography of diaphragm muscle     

The rapid efficacy of abatacept in a patient with rheumatoid vasculitis

We report a case of rheumatoid vasculitis (RV) that responded well to abatacept, a cytotoxic T lymphocyte-associated antigen 4 (CTLA4)-immunoglobulin fusion protein. A 38-year-old woman developed RV despite treatment with methotrexate and tumor necrosis factor (TNF) inhibitors. The effects of steroid therapy, immunoabsorption plasmapheresis, and interleukin-6 inhibitor were insufficient, however, administration of abatacept rapidly improved her clinical symptoms with almost normalization of the immunological findings. This is the first published case report of the successful treatment of RV with abatacept.     

Assessment of the differences in the short-term clinical outcomes of superotemporal and inferonasal Baerveldt glaucoma implantation surgeries performed via the pars plana route

AIM: To investigate and discover whether different insertion areas for Baerveldt glaucoma implant (BGI) surgery produce different outcomes in terms of the reduction of intraocular pressure (IOP). METHODS: This retrospective study involved the review of cases of patients admitted at Toho University Sakura Medical Center, who underwent BGI surgery via the pars plana route for the treatment of neovascular glaucoma. The patients were divided into two groups: the superotemporal insertion group [18 eyes in 16 subjects (13 males, 3 females; mean age 62.9±14.4y)] and the inferonasal insertion group [17 eyes in 15 subjects (11 males, 4 females; mean age 56.9±10.7y)]. The patients were followed up and re-evaluated at 12mo. The IOP reduction rate 12mo after surgery relative to preoperative IOP was compared between the two groups. RESULTS: The mean preoperative IOP was 31.1±10.0 mm Hg and postoperative IOP was 14.4±4.5 mm Hg in the superotemporal group, whereas for the inferonasal group, the mean preoperative IOP was 34.9±9.7 mm Hg and postoperative IOP was 15.9±3.7 mm Hg. The IOP reduction rate of the superotemporal group was 50.0%±19.0% and that of the inferonasal group was 51.2%±16.3%. There was no significant correlation between the two groups (Student’s t-test, P=0.590). CONCLUSION: There was no difference in the short-term clinical outcomes between superotemporal and inferonasal BGI performed via the pars plana route.     

Effect of alcohol addition on the structure and corrosion resistance of plasma electrolytic oxidation films formed on AZ31B magnesium alloy

The effect of the addition of alcohol to a Na₃PO₄-based electrolyte on plasma electrolytic oxidation (PEO) of AZ31B magnesium alloy was investigated. Anodization with spark discharge was conducted in Na₃PO₄-based electrolyte containing various alcohols (e.g., ethanol, ethylene glycol, and glycerol) at a constant current density of 200 A m⁻² and a constant temperature of 25 °C. Voltage–time curves during the PEO process, the film structure, surface roughness, crystallographic structure, composition, corrosion resistance, and withstand voltage were investigated using various analytical equipment and electrochemical measurements. When the electrolyte containing alcohol was used, the initial bending voltage was higher than that observed using the basic electrolyte without alcohol addition, as was the oscillation voltage during the PEO process. For a given amount of electricity supplied, the addition of alcohol into the basic electrolyte tended to increase the thickness and corrosion resistance of PEO films formed while effectively reducing surface roughness. In particular, the addition of a polyhydric alcohol (i.e., ethylene glycol and glycerol) could act not only as a leveler for the formation of compact film but also as an enhancer for film qualities, such as corrosion resistance and withstand voltage. The patterns observed for Na₃PO₄-based electrolyte containing alcohol also hold for Na₂SiO₃-based electrolyte containing alcohol.

Alcohol used as an additive could act not only as a leveler for the formation of compact film but also as an enhancer for film qualities, such as corrosion resistance and withstand voltage.     

The effects of 28-day early-life exposure to triphenyl phosphate (TPhP) on odor preference and sexual behavior in female rats

Many chemical substances are detectable in house dust, and they are consequently taken into our bodies via the mouth and nose. Triphenyl phosphate (TPhP), a flame retardant that has an estrogen-like effect in vitro, is present in house dust at high concentrations. Estrogen exposure during development has significant influences on reproductive behavior in rodents, and its effects persist until maturity. In the present study, we investigated the effect of early life exposure to TPhP on the reproductive behavior of female rats. Oral treatment with TPhP (25 or 250 mg/kg), ethinyl estradiol (EE; 15 μg/kg) as a positive control, or sesame oil as a negative control, were given to female rats (from birth to 28 days of age). The 8-week-old rats were bilaterally ovariectomized. At 12–15 weeks of age, the rats were subjected to odor preference and sexual behavior tests. In the odor preference test, the oil group showed significantly higher preference for male odor than female odor, but the low-dose TPhP treatment group lost the preference for male odor, indicating a possible outcome of early life TPhP exposure on sexual recognition. In the sexual behavior test, both the EE and TPhP treatment groups displayed significantly less proceptive behavior. These results suggest that early life exposure to TPhP disturbs the normal sexual behavior of female rats.