Bigeminal pulmonary vein ectopy suppressed by pulmonary vein isolation

A 58-year-old man with atrial fibrillation underwent pulmonary vein (PV) isolation (PVI). Bigeminal atrial premature beats persisted from the beginning of the PVI. The cardiac recordings from a basket catheter (BC) revealed the PV ectopic origin in the distal right superior PV. Successful PVI with the guidance of BC was confirmed by the appearance of concealed ectopy. Surprisingly, the PV ectopy completely disappeared immediately after the successful PVI. The findings suggest that the generation of PV trigger is sometimes dependent on left atrial input and that the underlying mechanism of the PV trigger may have been triggered activity or reentry.     

Vagal reflex provoked by radiofrequency catheter ablation in the right aortic sinus cusp: a Bezold–Jarisch-like phenomenon

A 66-year-old woman with idiopathic premature ventricular contractions with a left bundle branch block QRS morphology and left inferior axis underwent electrophysiologic testing. Successful radiofrequency ablation was achieved in the right coronary cusp (RCC). However, radiofrequency ablation at sites adjacent to the successful ablation site provoked sinus bradycardia followed by atrioventricular conduction block. That phenomenon might be explained by a vagal reflex through stimulation of vagal pathways or receptors in the anterior epicardial fat pads neighboring to the RCC. A vagal reflex should be kept in mind as a complication during catheter ablation of ventricular arrhythmias originating from the RCC.     

Flame retardance-donated lignocellulose nanofibers (LCNFs) by the Mannich reaction with (amino-1,3,5-triazinyl)phosphoramidates and their properties

Nitrogen/phosphorus-containing melamines (NPCM), a durable flame-retardant, were prepared by the successive treatment of ArOH (Ar = Br_nC₆H_5−n, n = 0, 1, 2, and 3) with POCl₃ and melamine monomer. The prepared flame-retardants were grafted through the CH₂ unit to lignocellulose nanofibers (LCNFs) by the Mannich reaction. The resulting three-component products were characterized using FT-IR (ATR) and EA. The thermal behavior of the NPCM-treated LCNF fabric samples was determined using TGA and DSC analyses, and their flammability resistances were evaluated by measuring their Limited Oxygen Index (LOI) and the UL-94V test. A multitude of flame retardant elements in the fabric samples increased the LOI values as much as 45 from 20 of the untreated LCNFs. Moreover, the morphology of both the NPCM-treated LCNFs and their burnt fabrics was studied with a scanning electron microscope (SEM). The heat release lowering effect of the LCNF fabric against the water-based paint was observed with a cone calorimeter. Furthermore, the mechanical properties represented as the tensile strength of the NPCM-treated LCNF fabrics revealed that the increase of the NPCM content in the PP-composites led to an increased bending strength with enhancing the flame-retardance.

LCNFs were grafted with nitrogen/phosphorus-containing melamines to achieve potent flame-retardance and converted to PP-composites of improved mechanical properties.     

The Priority of Non-HDL-C Assessment to Predict New Lesions among Stable Angina Patients with Strong Statins

Aim: In this study, we aim to examine the clinical meaning of low-density lipoprotein cholesterol (LDL-C) ＜70 mg/dL as assessed by Friedewald equation [LDL-C (F)] and Martin method [LDL-C (M)] and non-high-density lipoprotein cholesterol (HDL-C) ＜100 mg/dL on the occurrence of new lesions among Japanese patients with stable angina who underwent percutaneous coronary intervention (PCI) and were prescribed with strong statins. Methods: Among the 537 consecutive stable angina patients who had underwent PCI and had been prescribed with strong statins, the association between the occurrence of new lesions with myocardial ischemia at the 9-month follow-up coronary angiography and ≤ 2 years after PCI and baseline characteristics were assessed. Results: New lesions appeared 9 months and ≤ 2 years after PCI in 31 and 90 patients, respectively. Multivariate logistic regression analysis revealed diabetes mellitus (DM) was significantly associated with the occurrence of new lesions ≤ 2 years after PCI [odds ratio (OR) 1.71, 95 % confidence interval (CI) 1.06–2.83,p=0.031], and only non-HDL-C ≥ 100 mg/dL was associated with the occurrence of new lesions both at 9 months and ≤ 2 years after PCI [OR 1.80, 95 % CI 1.10–3.00,p=0.021 and OR 1.85, 95 % CI 1.13–3.07,p=0.016]. Conclusions: Non-HDL-C ≥ 100 mg/dL was determined to be the independent risk factor for the occurrence of new lesions 9 months and ≤ 2 years after PCI among stable angina patients with strong statins. Residual risk after PCI should be considered by assessing not only DM but also non-HDL-C beyond the scope of LDL-C-lowering therapy with strong statins.     

Case of Mycobacterium haemophilum misdiagnosed as Mycobacterium intracellulare due to one base insertion in the bacterial genome

Mycobacterium haemophilum is a slow‐growing, non‐tuberculous mycobacteria that causes cutaneous infection. We describe a case of cutaneous infection in a 68‐year‐old Japanese man with polymyositis. This was caused by M. haemophilum harboring one base insertion in gene sequence. At first, the causal microorganism was misidentified as M. intracellulare by COBAS^® TaqMan^® MAI test. However, poor growth on Ogawa media and growth enhancement on 7H11C agar around a hemin‐containing disk prompted us to reinvestigate the causal microorganisms, which were revealed to be M. haemophilum. Amplified polymerase chain reaction products were sequenced, and the 16S rRNA gene, rpoB, hsp65 and internal transcribed spacer region sequences showed a 100%, 100%, 99.66% and 99.7% match, respectively, with the corresponding regions of M. haemophilum, but it harbored a novel gene sequence in hsp65. The sequences determined by gene analysis of the M. haemophilum strain were deposited into the International Nucleotide Sequence Database. Although numerous cases of M. haemophilum infection have been reported in other countries, only six cases have been reported in Japan to date. It could be possible that this novel mutation lead to misdiagnosis. As M. haemophilum prefers a lower growth temperature (30–32°C) and it requires iron in the culture medium, M. haemophilum could be misidentified or overlooked. Accordingly, a M. haemophilum infection should be considered in cases of cutaneous infection of the body sites, of which surface temperature is low.     

Connexin 26 distribution in gap junctions between melanocytes in the human vestibular dark cell area

We have previously demonstrated the presence of gap junctions between melanocytes in the human vestibular organ and have speculated that melanocytes function in maintaining the homeostasis of the microenvironment of the inner ear. The purpose of the present study was to characterize the expression and ultrastructural localization of connexin (Cx) protein in melanocytes of the human vestibular organs. Surgical material was obtained from patients operated on for vestibular schwannoma and was processed for light microscopy, confocal laser scanning microscopy, conventional TEM, and immuno TEM. The specimens were labeled with anti-Cx26, Cx32, and Cx43 antibodies and examined by light microscopy. Specimens were also labeled with anti-Cx26 antibody and examined by laser microscopy and immuno-TEM methods. The specimens examined in this study were mainly dark cell areas from the human vestibular organ, whose epithelial and subepithelial layers are rich in melanocytes. Light-microscopic immunohistochemical studies showed positive labeling for Cx26 protein between subepithelial melanocytes, and Cx32 was also detected. Use of anti-Cx26 antibody and confocal laser scanning microscopy revealed high levels of Cx26 around the subepithelial melanocytes. Post-embedding immuno-gold transmission electron microscopy showed significant aggregation of gold particles (33.97 +/- 8.01% of total gold particles) around the gap junctions of the subepithelial melanocytes. The results of this study indicated that melanocytes are connected through gap junctions that mainly contain Cx26. This suggested that the melanocytes in the human vestibular organ may play a role in transporting material between the endolymph and perilymph.