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A 26-year-old Japanese woman developed a fever, myalgia and gait disturbance one day after receiving the second dose of the mRNA-1273 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine. A neurological examination revealed symmetrical weakness and myalgia in proximal lower limbs, and a blood examination showed prominent elevation of creatinine kinase. Magnetic resonance imaging (MRI) revealed a high signal intensity in the thigh muscles on short-tau inversion recovery images, and antibody testing revealed positive findings for anti-signal recognition particle (SRP) antibody. Thus, anti-SRP antibody-positive immune-mediated myopathy was diagnosed. We initiated immunotherapy, and she was ultimately able to walk stably.

A 70-year-old woman presented with a 6-year history of cognitive dysfunction, neurogenic bladder, constipation and recurrent vomiting, and gradual worsening of symptoms. At the first admission to our department, she was also found to have hepatic encephalopathy due to intrahepatic portosystemic shunt. Head MRI revealed abnormal signal intensity at the corticomedullary junction, the splenium of the corpus callosum, and bilateral middle cerebellar peduncles on DWI. She was diagnosed with intranuclear inclusion disease (NIID) based on skin biopsy and genetic testing of NOTCH2NLC. In a retrospective review of serial head MRI findings for ten years, abnormal signal intensity at the corticomedullary junction and the splenium of the corpus callosum on MRI existed prior to the onset of cognitive dysfunction, and expanded gradually. For early diagnosis of NIID, it is important to focus not only on the characteristic high signal intensity at the corticomedullary junction, but also on the signal at the splenium of the corpus callosum from the early stage.

A 33-year-old man with an unremarkable family history has had limb muscle weakness, joint contracture and skeleton deformation from early childhood. He was diagnosed with spinal muscular atrophy (SMA) by a pediatrician. He needed assistance and used orthoses in his daily life. There was no subjective sensory disturbance. However, physical examination showed slight sensory impairment, and nerve conduction study indicated sensory motor axonal neuropathy. This finding suggested Charcot-Marie-Tooth disease (CMT). Gene analysis detected MORC2 S87L mutation, leading to a diagnosis of CMT type 2Z. Patients with MORC2 S87L mutation are known to exhibit a severe phenotype, and may mimic SMA. It is important to demonstrate subclinical sensory neuropathy in patients with MORC2 S87L mutation mimicking SMA.

一般に，小型の板ばね部品の製造には，金型の製造とそれを用いた成形および熱処理の工程が必要である．しかしながら，その試作や小ロットの製造において金型の製造に時間とコストを要し，さらに熱処理における工程制御が難しいため，その場合には多くの手作業による工程が必要となっている．そこで著者らは，その試作や小ロットの製造における自動化を目指して，小出力半導体レーザを用いたレーザ焼入れフォーミングを提案する．本報では，その基礎現象を解明するためにレーザ照射時の薄鋼板の変形の様子をモニターする．さらに赤外線サーモグラフィにより，その温度分布も観察する．それらの結果より，面内方向の熱の蓄熱作用が，面外方向のフォーミングプロセスに影響することを解明した．, The die set and the heat treatment processes are needed to fabricate small size flat spring in general. However, a problem has been emerged that there are many traditional handmade processes because it takes long time to manufacture the die set, its cost is higher and the heat treatment control is difficult in prototype parts and small lot production. We therefore propose a hybrid laser hardening and forming method with a small power diode laser as an automatic controlled system to manufacture the small size plate spring for prototype and small lot production. In the present report, we attempt to monitor the deformation of thin steel plate during laser irradiation to investigate the basic phenomena. On the other hand, we observe the temperature distribution on the thin plate during laser irradiation with an infrared thermography. As a result, it can be seen that the thermal storage in-plane direction affects the laser forming process.

In recent years, the recycling of resources has become important because of the aggravation of global environmental concerns. In light of this, it is necessary to minimize the resource needs of current production systems. This concept is called sustainable development. When this concept is applied to machine tools, the assumption is that small parts should be processed using small machines. Additionally, the diversification of consumer needs and the ephemeralization of product life cycles are progressing in industry. As a result, the overall production system has changed from high-mix low-volume production manufacturing, to variant types in variable quantity. In this background, the cell production system is receiving attention as a production system that can achieve variant types in variable quantity. The cell production system also requires miniaturization and process consolidation of machine tools, which has given rise to the need to consolidate heat treatments, especially as part of the process consolidation of machine tools. Laser beams have proved to be effective heat sources when integrated into heat-treatment processes, such as quenching and tempering on machine tool tables. On the other hand, In the case of the thin plate, it is well known that the deformation of a plate occurs due to laser irradiation, as named a laser forming. The laser forming is also effective to generate the complex shape without a press die set. Thus, we propose that the hybrid process of laser heat treatment and forming of thin plate with a small power semiconductor laser, and demonstrate that the proposed method makes it feasible to generate the hardened sheet metal products with a compact machine tools. Moreover, considering the power consumption in laser quenching and forming process, we investigate an appropriate laser irradiation condition from a view of reducing the environmental burden.