Objective We developed an assay that detects autoantibodies against the main immunogenic region (MIR) located at the extracellular end of the nicotinic acetylcholine receptor (AChR) a subunit, and investigated its clinical relevance in myasthenia gravis (MG). Methods In this retrospective cohort study, we measured MIR antibody (Ab) titres in sera obtained before treatment and analysed their associations with clinical parameters in 102 MG patients from two neurological centres. MIR Ab titres were determined using a modified competition immunoprecipitation assay in the presence or absence of monoclonal antibody 35. Results 11 of 23 (47.8%) ocular type and 66 of 72 (91.7%) generalised type MG patients were positive for the presence of MIR Abs, defined as a titre >16.8% (3 SDs above the mean for 70 healthy controls). A significantly higher MIR Ab titre (p<0.001) was shown in generalised type (47.9619.2%) rather than in ocular type MG patients (16.468.4%). Bivariate regression analysis using both titre levels of MIR Ab and routine AChR binding Ab as variables revealed MIR Abs to be an exclusive indicator positively associated with disease severity (Myasthenia Gravis Foundation of America classification, p<0.0001; Quantitative MG score, p¼0.008), the presence of bulbar symptoms (p<0.0001) and thymoma (p¼0.016), and negatively associated with ocular MG (p<0.0001). Conclusions MIR Ab titre levels show much better correlations with factors related to disease severity compared with AChR binding Ab titres. The MIR Ab assay may be useful for predicting MG symptom severity, especially for discriminating between ocular and generalised types of MG.

Japanese spotted fever (JSF), first reported in 1984, is a rickettsial disease characterized by high fever, rash, and eschar formation. A 61-year-old man was admitted to a local hospital in Nagasaki City, Japan, after several days of high fever and generalized skin erythema. His condition deteriorated and laboratory findings indicated disseminated intravascular coagulation (DIC). The patient was transferred to our hospital with mental disturbance and status epilepticus. Treatment included minocycline, and new quinolone. Definitive diagnosis was made with a serological test showing increased antibody levels against Rickettsia japonica. Rickettsial infections are rare, but should be seriously considered for the differential diagnosis of aseptic meningitis and encephalitis, as they show no response to conventional antibiotic treatment.

Background: The differences in the characteristics of thymus histology, coexisting autoimmune

要旨： 【目的】当院を hub，離島施設を spoke とした hub-and-spoke 型モデルによる telestroke に おいて，drip-and-ship(DS)法による rt-PA 投与の安全性/有効性を検討し，drip-and-stay 法導入の 可能性を探る． 【方法】2012 年 4 月から 2021 年 10 月までに rt-PA 治療が行われた急性期脳梗塞 203 例を，離島群 61 例，当施設群 142 例に分け，症候性頭蓋内出血(sICH) /臨床的転帰(mRS) を検討した． 【結果】離島群/当施設群の sICH 発生率と 30 日後の mRS 0-2 比率は，4.9% / 4.1%， 36.1% / 38.0% であり，有意差を認めなかった．両群で脳外科的緊急処置が必要な sICH はみられな かった． 【結論】離島群への DS 法は，当施設群と同等に安全かつ有効であり，DS 法施行例は，必 ずしも全例で緊急転院搬送による管理を必要としない可能性が示唆された．

Bow hunter's stroke is a rare cause of vertebrobasilar infarction. There is no consensus regarding the optimal treatment. We herein report a case of bow hunter's stroke successfully treated by endovascular treatment. A 70-year-old man presented with central vertigo. Magnetic resonance imaging (MRI) showed posterior circulation infarcts. Dynamic angiography revealed thrombus formation and hypoperfusion of the right vertebral artery upon head rotation to the left. Endovascular parent artery occlusion of the right vertebral artery was performed, and there was no recurrence at follow-up MRI. Endovascular parent artery occlusion might be a useful treatment for bow hunter's stroke.