Radiofrequency ablation in a porcine liver model： Effects of transcatheter arterial embolization with iodized oil on ablation time, maximum output, and coagulation diameter as well as angiographic characteristics

AIM:To evaluate the effects of combined radiofrequen-cy ablation and transcatheter arterial embolization with iodized oil on ablation time,maximum output,coagula-tion diameter,and portal angiography in a porcine liver model. METHODS: Radiofrequency ablation (RFA) was applied to in vivo livers of 10 normal pigs using a 17-gauge 3.0 cm expandable LeVeen RF needle electrode with or with-out transcatheter arterial embolization (TAE) with iodized oil (n = 5). In each animal,2 areas in the liver were ab-lated. Direct portography was performed before and af-ter RFA. Ablation was initiated at an output of 30 W,and continued with an increase of 10 W per minute until roll-off occurred. Ablation time and maximum output until roll-off,and coagulated tissue diameter were compared between the 2 groups. Angiographic changes on portog-raphy before and after ablation were also reviewed. RESULTS: For groups with and without TAE with iodized oil,the ablation times until roll-off were 320.6 ± 30.9 seconds and 445.1 ± 35.9 seconds,respectively,maxi-mum outputs were 69.0 ± 7.38 W and 87.0 ± 4.83 W and maximal diameters of coagulation were 41.7 ± 3.85 mm and 33.2 ± 2.28 mm. Significant reductions of abla-tion time and maximum output,and significantly larger coagulation diameter were obtained with RFA following TAE with iodized oil compared to RFA alone. Portography after RFA following TAE with iodized oil revealed more occlusion of the larger portal branches than with RFA alone. CONCLUSION: RFA following TAE with iodized oil can increase the volume of coagulation necrosis with lower output and shorter ablation time than RFA alone in nor-mal pig liver tissue.     

Successful treatment of hypovascular advanced hepatocellular carcinoma with lipiodol-targetting intervention radiology

We report a case of hypovascular advanced hepa-tocellular carcinoma (HCC) successfully treated with a novel combination therapy of percutaneous ethanol-lipiodol injection (PELI) and intervention radiology (IVR),lipiodol-targetting IVR (Lipi-IVR). The present case had a hypovascular HCC (3 cm in diameter) located in the S6 region of the liver. Although the tumor was not detectable at all by both of early and late phase of helical dynamic computed tomography (CT),it could be detected by ultrasonography (US) as a low echoic space occupying lesion (SOL) beside the gallbladder and right kidney. Serum levels of alpha fetoprotein (AFP) and AFP-L3 were extremely high. Combination therapy of PELI,firstly reported in our department,and IVR (PELI and IVR,lipiodol-targetting IVR) was performed twice for the treatment. PELI could effectively visualize the location of the tumor for IVR treatment and show the presence of a thin blood vessel branching from the right hepatic artery flowing into the lipiodol deposit. After treatment,the serum levels of AFP and AFP-L3 were rapidly decreased to normal and maintained for more than eight months. Thus,this case expressing the tremendous effect might give us insight into the effectiveness of the novel combination therapy of PELI and IVR for the treatment of hypovascular HCC.     

New Aspects for the Treatment of Cardiac Diseases Based on the Diversity of Functional Controls on Cardiac Muscles: The Regulatory Mechanisms of Cardiac Innervation and Their Critical Roles in Cardiac Performance

The heart is abundantly innervated, and the nervous system precisely controls the function of this organ. The density of cardiac innervation is altered in diseased hearts, which can lead to unbalanced neural activation and lethal arrhythmia. For example, diabetic sensory neuropathy causes silent myocardial ischemia, characterized by loss of pain perception during myocardial ischemia, and it is a major cause of sudden cardiac death in diabetes mellitus. Despite the clinical importance of cardiac innervation, the mechanisms underlying the control of this process remain poorly understood. We demonstrate that cardiac innervation is determined by the balance between neural chemoattractants and chemorepellents within the heart. Nerve growth factor (NGF), a potent chemoattractant, is synthesized abundantly by cardiomyocytes, and is induced by the upregulation of endothelin-1 during development. By comparison, the neural chemorepellent Sema3a is expressed at high levels in the subendocardium in the early stage of embryogenesis and is downregulated as development progresses, leading to epicardial-to-endocardial transmural sympathetic innervation patterning. We also show that the downregulation of cardiac NGF is a cause of diabetic neuropathy and that NGF supplementation prevents silent myocardial ischemia in diabetes mellitus. Both Sema3a-targeted and Sema3a-overexpressing mice display sudden cardiac death or lethal arrhythmias due to disruption of innervation patterning. The present review focuses on the regulatory mechanisms controlling cardiac innervation and the critical roles of these processes in cardiac performance.     

Protective effects of the whisky congeners on ethanol-induced gastric mucosal damage

BACKGROUND: The ingestion of both ethanol and whisky can induce acute gastrointestinal bleeding. The effects of the congeners, substances other than ethanol in whisky, on the ethanol-induced gastric mucosal damage were examined in the rat model. METHODS: After the whisky congeners were intragastrically administered previous to or simultaneous with ethanol ingestion, the gastric damage was macroscopically and microscopically measured. RESULTS: The simultaneous administration of the whisky congeners at a dose of 5 mg/kg body weight, which corresponds to the concentration of congeners contained in whisky, with 50% ethanol did not inhibit the hemorrhagic lesions, but inhibited them at a dose of 150 mg/kg. The treatment with the whisky congeners 30 minutes before the ethanol ingestion prevented the ethanol-induced gastric damage in a dose-dependent manner at 0.5 to 150 mg/kg. The butanol extract of the congeners revealed the strongest prevention compared with the ethyl acetate extract or the water fraction. The administration of indomethacin 60 minutes before the congener treatment partly inhibited the protective effects of the congeners, indicating the partial contribution of prostaglandins in this mechanism. The congeners did not prevent the mucosa by action as a "mild irritant" because the immunohistochemical studies using the antimucin monoclonal antibodies showed that no damage was induced by the administration of the congeners. CONCLUSION: The present results showed that the whisky congeners have a protective activity against ethanol-induced gastric mucosal injury.     

Which Has Superior Acid-Suppressive Effect, 10 Mg Omeprazole Once Daily or 20 Mg Famotidine Twice Daily? Effects of Single or Repeated Administration in Japanese <Emphasis Type="Italic">Helicobacter Pylori</Emphasis>-Negative CYP2C19 Extensive Metabolizers

Low-dose omeprazole is superior to full-dose famotidine in maintenance therapy for gastroesophageal reflux disease, whereas “on-demand” famotidine is more effective for relief of episodes of heartburn. To explain this apparent discrepancy, intragastric pH was measured for 24-hr seven times in eight Japanese Helicobacter pylori-negative cytochrome P450 2C19 extensive metabolizers; on Days 1, 8, and 15 of repeated administration of 10 mg of omeprazole once daily and of 20 mg of famotidine twice daily and before medication. During repeated administration of omeprazole, mean intragastric pH and % time that intragastric pH > 4.0 were significantly higher and became greater. With famotidine, although these parameters were significantly higher, the degrees became smaller. Consequently, acid-suppressive effect was in the order; omeprazole < famotidine on Day 1, omeprazole≈famotidine on Day 8, and omeprazole >famotidine on Day 15. This discrepancy possibly results from the “potentiation” of acid-suppressive effect of omeprazole and the “tolerance” phenomenon in respect to famotidine.