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Charcot-Marie-Tooth disease (CMT) is a spectrum of clinically and genetically heterogeneous peripheral neuropathies. CMT can be classified into demyelinating, intermediate, or axonal neuropathy based on clinical, histopathological, and electrophysiological findings. Approximately 140 genes have been reported to be associated with CMT. Mutations in the myelin protein zero (MPZ), ganglioside-induced differentiation related protein 1 (GDAP1), and neurofilament light-chain polypeptide gene (NEFL) genes have been reported to cause all three types of CMT, which is noteworthy because most CMT-related genes cause a single type of neuropathy (either demyelinating or axonal). In contrast, it remains unclear why these genes cause several types of CMT. CMT is presently incurable; however, ongoing attempts to treat CMT with various drugs and dietary supplements have increased the importance of an exact genetic diagnosis for precision medicine. Therefore, it is important to identify the causative mutations and compare the associated clinical characteristics. Taken together, a comparison of causative mutations and clinical features of patients with MPZ, GDAP1, and NEFL mutations will be the first step in understanding how different types of CMT are caused, and will enable a molecular genetic diagnosis. In this review, we describe the clinical, electrophysiological, and genetic characteristics of MPZ-, GDAP1-, and NEFL-related CMT.

Osmotic demyelination syndrome (ODS) is an acute demyelinating disorder characterized by the loss of myelin in the center of the basis pons which is defined as central pontine myelinolysis (CPM) and demyelination process in locations outside the pons which is defined as extrapontine myelinolysis (EPM). ODS including CPM and EPM is mainly caused by the rapid correction of hyponatremia. However, there are several reports of ODS in medical condition such as malnutrition, alcoholism, liver transplantation, malignancy, sepsis, electrolyte imbalance including hypernatremia, hypokalemia, hypophosphatemia, and chronic illness. Rarely, ODS was reported in patients with hyperammonemia or hyperbilirubinemia without sodium fluctuations. The symptoms usually correspond to the lesion site and EPM precedes CPM. Because ODS may be irreversible, prevention is more important. Here, we report a case of ODS secondary to the hyperammonemia and hyperbilirubinemia, as it can have unfavorable prognosis.

High-power terahertz radiation was observed to be emitted from a gas jet irradiated by 100-terawatt-class laser pulses in the laser-wakefield acceleration of electrons. The emitted terahertz radiation was characterized in terms of its spectrum, polarization, and energy dependence on the accompanying electron bunch energy and charge under various gas target conditions. With a nitrogen target, more than 4 mJ of energy was produced at

Duplication and deletion of the peripheral myelin protein 22 (PMP22) gene cause Charcot-Marie-Tooth disease type 1A (CMT1A) and hereditary neuropathy with liability to pressure palsies (HNPP), respectively, while point mutations or small insertions and deletions (indels) usually cause CMT type 1E (CMT1E) or HNPP. This study was performed to identify PMP22 mutations and to analyze the genotype–phenotype correlation in Korean CMT families. By the application of whole-exome sequencing (WES) and targeted gene panel sequencing (TS), we identified 14 pathogenic or likely pathogenic PMP22 mutations in 21 families out of 850 CMT families who were negative for 17p12 (PMP22) duplication. Most mutations were located in the well-conserved transmembrane domains. Of these, eight mutations were not reported in other populations. High frequencies of de novo mutations were observed, and the mutation sites of c.68C>G and c.215C>T were suggested as the mutational hotspots. Affected individuals showed an early onset-severe phenotype and late onset-mild phenotype, and more than 40% of the CMT1E patients showed hearing loss. Physical and electrophysiological symptoms of the CMT1E patients were more severely damaged than those of CMT1A while similar to CMT1B caused by MPZ mutations. Our results will be useful for the reference data of Korean CMT1E and the molecular diagnosis of CMT1 with or without hearing loss.

Extracorporeal shock wave therapy (ESWT) can reduce breast cancer-related lymphedema (BCRL). However, evidence of the long-term effectiveness of ESWT on BCRL is sparse. The aim of the study was to investigate whether ESWT has long-term effects on BCRL. We enrolled patients with stage 2 lymphedema. The 28 female patients were randomly divided into the ESWT group (n = 14) and the control group (n = 14). ESWT was applied thrice a week for a total of 3 weeks with an intensity of 0.056 to 0.068 mJ/mm2 and a frequency of 4 Hz. Complex decongestive therapy (CDT) was applied in both groups. The arm circumference, fluid volume, ratio of water content, and skin thickness were measured. Patients were evaluated at before treatment, 3 weeks after ESWT completion, and 3 months post-ESWT completion. The ESWT group, the circumference of the whole arm, volume, ratio of water content, QuickDASH score, and skin thickness showed statistically significant improvement at 3 weeks and 3 months post-treatment. When comparing the changes in measurement between the two groups at 3 weeks and 3 months post-treatment, ESWT group showed statistically significant improvement in circumference (cm) below the elbow, ratio of water content and skin thickness at 3 weeks and 3 months post treatment. Overall, ESWT improved lymphedema in patients with stage 2 BCRL, and the effects persisted for at least 3 months. Therefore, ESWT may be an additional treatment method for patients with lymphedema.