A Case of Nemaline Myopathy With Sleep-Related Hypoventilation Diagnosed Using Polysomnography During Daytime Napping.

This is the case of a 49-year-old woman who was admitted to the hospital for a close examination of pulmonary hypertension; however, the next morning, she developed carbon dioxide (CO2) narcosis and was started on artificial ventilation. As pulmonary arterial hypertension was ruled out, the patient was extubated, and 24-hour transcutaneous partial pressure of carbon dioxide (PCO2)(transcutaneous carbon dioxide (TcPCO2)) monitoring was performed to diagnose sleep-related hypoventilation. Polysomnography (PSG) during daytime napping revealed markedly decreased chest motion and a "pseudo-central event," which was neither central nor obstructive hypopnea. Based on the PSG results and physical examination findings, a neuromuscular disorder was suspected, and a muscle biopsy was performed to diagnose nemaline myopathy. Neuromuscular diseases are widely recognized for their association with sleep-disordered breathing; thus, sleep-related hypoventilation should also be considered. Monitoring of TcPCO2 and PSG are useful tools in identifying the cause of hypoventilation; however, overnight PSG may cause CO2 narcosis in some diseases. In such cases, PSG may be beneficial during daytime napping.

Invasive Tracheobronchial Aspergillosis with Bronchial Ulcers Complicated by Nontuberculous Mycobacterial Disease.

Invasive tracheobronchial aspergillosis (ITBA) complicated by nontuberculous mycobacteria (NTM) is rare. An 88-year-old man was admitted for hemoptysis. Bronchoscopy revealed bronchial ulcers, and a tissue biopsy showed Aspergillus fumigatus. He was diagnosed with ITBA, which improved with voriconazole. During treatment, infiltrative shadows appeared in his lungs, and bronchoscopy was performed once again. A non-necrotic epithelioid granuloma and Mycobacterium intracellulare were detected in the biopsy specimen. He was diagnosed with NTM disease. It is important to note that tracheobronchial ulcers may cause hemoptysis and to identify the etiology and treat it appropriately when multiple bacteria are found.

Syntaxin-3 is required for melanosomal localization of Tyrp1 in melanocytes.

Melanogenic enzymes are transported by vesicular/membrane trafficking to immature melanosomes in melanocytes where they catalyze the synthesis of melanin pigments. Although several factors involved in melanogenic enzyme trafficking have been identified in the past decade, involvement of the SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) proteins, which generally mediate membrane fusion, on melanosomes in the process of melanogenic enzyme trafficking has never been investigated. In this study we identified syntaxin-3, which was originally described as a target SNARE protein at the plasma membrane, as a melanosome-resident protein and investigated whether syntaxin-3 is involved in the trafficking of the melanogenic enzyme Tyrp1 (tyrosinase-related protein 1) in mouse melanocytes. The results showed that knockdown of endogenous syntaxin-3 protein in melanocytes caused a dramatic reduction in Tyrp1 signals, especially from peripheral melanosomes, presumably as a result of lysosomal degradation of Tyrp1. They also showed that syntaxin-3 interacts with another target SNARE SNAP23 (synaptosome-associated protein of 23 kDa) and with vesicle SNARE VAMP7 (vesicle-associated membrane protein 7), which has been shown to be localized at Tyrp1-containing vesicles/organelles. These findings suggested that the SNARE machinery composed of VAMP7 on Tyrp1-containing vesicles and syntaxin-3 and SNAP23 on melanosomes regulates Tyrp1 trafficking to the melanosome in melanocytes.