Repulsive guidance molecule-a (RGMa), a glycosylphosphatidylinositol-anchored membrane protein, has diverse functions in axon guidance, cell patterning, and cell survival. Inhibition of RGMa attenuates pathological dysfunction in animal models of central nervous system (CNS) diseases including spinal cord injury, multiple sclerosis, and neuromyelitis optica. Here, we examined whether antibody-based inhibition of RGMa had therapeutic effects in a mouse model of Parkinson’s disease (PD). We treated mice with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and found increased RGMa expression in the substantia nigra (SN). Intraventricular, as well as intravenous, administration of anti-RGMa antibodies reduced the loss of tyrosine hydroxylase (TH)-positive neurons and accumulation of Iba1-positive microglia/macrophages in the SN of MPTP-treated mice. Selective expression of RGMa in TH-positive neurons in the SN-induced neuronal loss/degeneration and inflammation, resulting in a progressive movement disorder. The pathogenic effects of RGMa overexpression were attenuated by treatment with minocycline, which inhibits microglia and macrophage activation. Increased RGMa expression upregulated pro-inflammatory cytokine expression in microglia. Our observations suggest that the upregulation of RGMa is associated with the PD pathology; furthermore, inhibitory RGMa antibodies are a potential therapeutic option.

Preformed cuffed oral endotracheal tubes are widely used to intubate children undergoing oral surgery. To evaluate the efficacy and safety of oral Ring-Adair-Elwyn (RAE) Microcuff® pediatric endotracheal tubes, we retrospectively investigated the endotracheal tube exchange rate and associated complications in Japanese children younger than 2 years of age undergoing cheiloplasty or palatoplasty. The exchange rate was 3.5%, and although unplanned extubations occurred in 2 patients, no severe complications were observed. Our results suggest that oral RAE Microcuff® tubes are effective and safe for intubating Japanese children younger than 2 years of age, with a low tube exchange rate and minor complications.

We report a case of wide QRS tachycardia or ventricular tachycardia with a pulse after the administration of epinephrine under general anesthesia. After induction and achieving a sufficiently deep plane of general anesthesia, gauze soaked in a 1:100,000 epinephrine solution was applied to the patient's nasal mucosa and 1% lidocaine with 1:100,000 epinephrine was administered via intraoral infiltration. Several minutes after the start of surgery, the patient's blood pressure and heart rate suddenly increased and a wide QRS tachycardia was observed on the electrocardiogram, which then reverted to a normal sinus rhythm. According to the past reports, similar arrhythmias have occurred after administration of epinephrine in the head and neck. These findings suggest that anesthesia providers must be aware of the risks associated with epinephrine and local anesthetic use, particularly in the head and neck region.