Relationships between depolarization abnormality and repolarization abnormality in patients with Brugada syndrome: using body surface signal-averaged electrocardiography and body surface maps

INTRODUCTION: Repolarization and depolarization abnormalities have been reported to be related to Brugada syndrome. METHODS AND RESULTS: We evaluated the relationships between repolarization abnormality and depolarization abnormality using 48-lead unipolar signal-averaged electrocardiograms and 87-lead unipolar body surface maps in 15 patients with Brugada-type ECGs. Data were compared with those from healthy control subjects (n = 5) and within subgroups of Brugada syndrome with (n = 8) and without (n = 7) ventricular arrhythmias (VA) induced by programmed electrical stimulation (PES). Eighty-seven-lead body surface maps were recorded, and potential maps were constructed to evaluate elevation of the ST segment 20 ms after the J point. Forty-eight-lead signal-averaged ECGs were recorded, and isochronal maps of duration of the delayed potential (dDP) were constructed to evaluate the dDP in each lead. Potential maps showed that patients with Brugada-type ECG, especially those with VA induced by programmed electrical stimulation, had greater elevation of the ST segment in the right ventricular outflow tract, especially at E5. Isochronal maps of dDP in the Brugada-type ECG group showed that maximum dDP was located at E5 and that the area with long dDP was larger than that in the control subjects. The dDPs at E7, E5, F7, and F5 in the VA-inducible group were significantly longer than those in the VA-noninducible group. These results showed that the location of greater elevation in the ST segment coincided with the location of longer dDP. CONCLUSION: Repolarization abnormality and depolarization abnormality in the walls of both ventricles, especially in the right ventricular outflow tract, are related to the VA of Brugada syndrome.     

A novel murine model for non-alcoholic steatohepatitis developed by combination of a high-fat diet and oxidized low-density lipoprotein

Non-alcoholic steatohepatitis (NASH) is the hepatic manifestation of metabolic syndrome that is characterized by steatosis, inflammation, and fibrosis, and may progress to cirrhosis and carcinoma. To investigate its pathogenic processes, we established a novel murine model for NASH by combination of a high-fat diet (HFD) and oxidized low-density lipoprotein (oxLDL). Mice that received HFD for 23 weeks showed hepatic steatosis, slight fibrosis, and a high level of lipid peroxidation compared with a regular diet (RD)-fed mice. Hepatic injury and elevated tumor necrosis factor (TNF)-α mRNA expression were also detected in these mice. Moreover, oxLDL administration to HFD-fed mice during weeks 21-23 not only aggravated hepatic steatosis, fibrosis, and lipid metabolism, but also resulted in intense inflammation, including severe hepatic injury and inflammatory cell infiltration, which are the typical histological features of NASH. Inflammation was accompanied by increased gene expression of TNF-α and interleukin (IL)-6. Additionally, the livers of RD-fed animals treated with oxLDL during weeks 21-23 were characterized by foamy macrophages and inflammatory cell infiltration along with an elevated IL-6 mRNA level. These results suggest that an increased oxidative state, including HFD-induced intracellular lipid peroxidation and its extracellular source from oxLDL, is the actual trigger for hepatic inflammation in which liver injury is mediated by TNF-α and inflammatory cell accumulation is dependent on IL-6. HFD and oxLDL also induced insulin resistance in mice; additionally, oxLDL downregulated insulin secretion. In this model, CD36 overexpression was observed in the hepatocytes of HFD-fed mice and those treated with HFD and oxLDL, and in the hepatic macrophages of RD-fed mice immediately after oxLDL treatment. In vitro experiments indicated a rapid and transient elevation of CD36 on macrophage plasma membrane in response to oxLDL. Our findings demonstrate that CD36 expressed on hepatocytes and hepatic macrophages mediates the pathophysiology of NASH.     

Effective cyclophosphamide pulse therapy for an young infant with severe dermatomyositis

We herein report a 3 year-old boy, who showed proximal muscle weakness and pain at the age of one and a-half years. When he visited our hospital at the age of 1 year and 11 months, he could hardly move by himself. He also had difficulty in swallowing and suffered from multiple dermal ulcers. His blood test showed slightly elevated muscle enzyme activity, and magnetic resonance imaging suggested severe inflammation of the muscles. Radiological examination proved hypoperistalsis of the esophagus. With additional skin and muscle biopsies, we diagnosed him with juvenile dermatomyositis (JDM). Methyl-prednisolone pulse therapy was not effective enough, thus oral methotrexate, cyclosporine A and monthly cyclophosphamide pulse therapy were added. After the fourth cyclophosphamide pulse therapy, his muscular strength was restored, and the ulcers healed dramatically. Due to scarcity of severe cases, neither standardized classification nor grading system for severity in JDM has ever been established, which perplexes physicians in finding the best therapeutic strategy. Further investigation, experience and efforts are necessary to standardize an evaluating system and therapeutic strategy against JDM.     

Renal failure caused by plasma cell infiltration in multiple myeloma

We report on a case of severe renal failure in a 61-year-old female with multiple myeloma (MM). Two months prior to admission, the patient was diagnosed to have anemia and progressive renal failure associated with urinary Bence Jones protein and was referred to our hospital. A bone marrow biopsy revealed 40% plasma cells with κ light chain restriction. Thus, she was considered to have MM. A renal biopsy revealed neoplastic plasma cell infiltration within the kidney, moderate interstitial fibrosis, tubular atrophy, and punctate, electron-dense material along the peripheral capillary walls, tubular basement membrane, and in the interstitium of the kidney. This suggested that a combination of compression of the tubules and the microvasculature by the infiltrative process, and local light chain deposition-mediated tissue damage might be implicated in the development of renal failure in this patient. Despite a remission of bone marrow plasmacytosis with a bortezomib-based regimen, her renal function gradually deteriorated and a periodic hemodialysis program was finally required. Although the clinical impact of the direct kidney infiltration of neoplastic plasma cells on the longitudinal changes in renal function remains to be delineated, it is reasonable to consider that the infiltration of neoplastic plasma cells associated with local light chain depositions may result in irreversible renal injuries. Obviously, further studies and accumulation of additional experience with renal biopsy are required to better determine the precise and prognostic relationship between renal outcome and morphological alterations among MM patients with varying degrees of renal impairment.     

Fulminant hepatitis after allogenic bone marrow transplantation caused by reactivation of hepatitis B virus with gene mutations in the core promotor region

Under immunosuppressive conditions after hematopoietic stem cell transplantation (HSCT), even if hepatitis B virus (HBV) antigen is negative but hepatitis B surface antibody (HBsAb) or hepatitis B core antibody (HBcAb) is presented, HBV reactivates and sometimes causes fulminant hepatitis. However, it remains unclear which patients will develop fulminant hepatitis, or whether fulminant hepatitis is caused by host-related factors or by virus-related factors. A 30-yr-old man with a history of aplastic anemia since 3 yr of age underwent allogenic BMT, when HBsAb and HBcAb were positive but HBs antigen (HBsAg) was negative. The donor was negative for HBsAg, HBsAb and HBcAb. After transplantation, the patient was complicated by acute graft-vs.-host disease (GVHD), cytomegalovirus infection, intestinal thrombotic microangiopathy and aspergillus colitis. Chronic GVHD was well controlled by FK506 and prednisolone. Twenty months after transplantation, the patient was admitted with general fatigue and liver dysfunction and was found to be positive for HBsAg and HBeAg. His serum HBV-DNA level was >8.8 log of the genome equivalent (LGE)/mL. Therefore, he was diagnosed as having hepatitis B caused by HBV reactivation and 100 mg/d lamivudine treatment was started. However, jaundice and hepatic failure deteriorated and became fatal. On analysis of the HBV-DNA, two adjacent gene mutations in the core promoter region (T1762/A1764) were detected. Increased replication of the mutated HBV might have caused HBV reactivation which progressed to fulminant hepatitis.     

Two cases of idiopathic superior laryngeal neuralgia treated by superior laryngeal nerve block with a high concentration of lidocaine

Carbamazepine therapy is among the most effective drug regimens to treat patients who have superior laryngeal neuralgia similar to trigeminal neuralgia. However, some patients are resistant to carbamazepine. We report two patients with superior laryngeal neuralgia who were successfully treated with superior laryngeal block using high concentrations of lidocaine, after treatment with carbamazepine failed.     

The occurrence of spontaneous functional and nonfunctional orofacial activities in subjects without pain under laboratory conditions: a descriptive study

AIMS: To assess the occurrence and the modality of spontaneous orofacial behaviors of awake healthy subjects without pain who were unaware of bruxism during wakefulness. METHODS: Sixteen asymptomatic subjects read silently for 30 minutes while polygraphic recordings, including electromyographic (EMG) activity from masticatory and leg muscles, chest respiratory movements, and the movements and sounds of larynx, were made with simultaneous audio-video monitoring. Orofacial behaviors were scored based on the polygraphic and audio-video records. The activity and duration of masseter EMG bursts were calculated for the types of orofacial behaviors. RESULTS: The number of orofacial behaviors varied between subjects; swallowing was most frequently observed. Approximately half of the orofacial behaviors occurred closely with body movements. Of all masseter EMG bursts detected, 55% were associated with functional orofacial behaviors, while 45% were regarded as nonfunctional. More than 80% of these masseter bursts lasted for less than 2 seconds, with an activity less than 20% of maximal voluntary clenching. These values did not differ between the types of associated orofacial behaviors. CONCLUSION: Although the occurrence of spontaneous orofacial motor activity is variable, asymptomatic subjects can exhibit substantial masseter bursts during wakefulness that are not associated with functional orofacial behaviors. The use of physiological and audio-video records permits spontaneous orofacial behaviors to be specifically identified, thereby allowing nonfunctional masseter EMG activity to be differentiated from functional masseter EMG activity.