Background: Myocardial ischemia causes accumulation of extracellular myocardial K⁺ ([K⁺]_e). However, the relation between [K⁺]_e, and local coronary venous K⁺, i.e., K⁺ in the great coronary vein ([K⁺]_gcv) has not been established. To determine the sensitivity of [K⁺]_gcv as a marker of myocardial ischemia, we continuously measured [K⁺]_e, using intramyocardial K⁺-selective plunge electrodes, and [K⁺]_gcv, using a catheter-tip K⁺ electrode inserted into the great cardiac vein, during two types of ischemia. Methods and Results: In in-situ pig hearts, ischemia was induced by implementing a progressive decrease in carotid-to-left anterior descending artery (LAD) shunt flow from 40 to 0 mL/min at constant heart rate (100-130/min) and a progressive increase in heart rate from 100 to 160 beats/min at the threshold flow. The progressive decrease in LAD flow to 5 mL/min caused parallel increases in [K⁺]_e (from 3.87 ± 0.37 to 8.65 ± 1.13 mM) and [K⁺]_gcv (from 3.87 ± 0.37 to 4.84 ± 0.43 mM). However, below 5 mL/min, [K⁺]_gcv failed to reflect the increase in [K⁺]_e and often decreased. The progressive increase in heart rate at the threshold flow caused parallel changes in [K⁺]_e (from 4.08 ± 0.36 to 4.87 ± 0.14 mM, n = 3) and [K⁺]_gcv (from 3.08 ± 0.42 to 4.18 ± 0.43 mM). The verapamil- and propranolol-induced changes in [K⁺]_e during low-flow ischemia were reflected by changes in [K⁺]_gcv. Conclusions: Change in [K⁺]_gcv is a sensitive marker of myocardial ischemia, except at very low coronary flow. Thus, [K⁺]_gcv can be used to detect early myocardial ischemia.

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Background: Complex electrocardiogram morphologies (atrial fibrillation [AF] nests) in sinus rhythm (SR) recorded by frequency domain techniques can serve as a pathologic substrate for atrial fibrillation (AF). We sought to characterize any direction-dependent and rate-dependent changes in dominant frequency (DF) and high DF sites in the left atrium (LA) in patients with AF. Methods: Eight patients with AF were included in the study. A basket catheter with 64 electrodes was placed in the LA. Forty-eight bipolar electrocardiograms were recorded during SR and during pacing from the high right atrium (HRA), proximal coronary sinus (CS), and distal CS at various pacing rates, ranging from 600 ms to 250 ms. The frequency domain measures of LA bipolar electrocardiograms were compared during SR and HRA, proximal CS, and distal CS. Results: The DF was found to be higher during proximal CS and distal CS pacing than during SR. The percentage of high DF (>70 Hz) sites was higher during distal CS pacing than during SR. The various pacing rates applied during HRA, proximal CS, and distal CS pacing did not affect the DF values. Conclusion: DF of atrial electrocardiograms obtained during SR was influenced by the direction of conduction but not by the pacing rate.

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Group B streptococcus (GBS) is a causative pathogen of meningitis and sepsis in neonates and early infants. To describe the characteristics of GBS meningitis in children, we studied 6 patients that were treated at the Department of Pediatrics and Child Health, Nihon University Itabashi Hospital. Among them, five were late onset cases and one was ultra-late onset. We determined the risk factors for neurological sequelae to be: a long period of initial symptoms before admission, septic shock at admission, the use of artificial ventilation, intractable seizure and a long serum CRP-positive period. There was no correlation between the capsular types and severity. Two cases had adverse outcomes and revealed strains that were less susceptible to ampicillin. Reconsideration is necessary to provide preventive measures against GBS in medical institutes.

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Mature teratoma of the ovary is the most common ovarian disease. However, due to its rarity, it is difficult to predict the occurrence of malignant transformation in mature teratoma. Current studies have suggested that preoperative factors include ovarian tumor size, tumor marker, and the age of the patient. We studied 471 patients with benign mature teratoma and 8 patients with malignant transformation who underwent surgery at the Department of Obstetrics and Gynecology, Nihon University Itabashi Hospital between 2003 and 2015. Most patients with malignant transformation in mature teratoma exhibited larger ovarian tumors, with high concentrations of squamous-cell-carcinoma antigen, and were older. We propose that the addition of considering the ovarian tumor size, tumor marker level, and patient age, along with imaging findings, will be effective in the preoperative differential diagnosis of mature teratoma and malignant transformation.

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Pancreatic body cancer is often judged to be unresectable due to vascular infiltration. When there is infiltration of the coeliac-artery by pancreatic cancer, some cases can be resectable. We removed the embolus of the common hepatic artery and maintained hepatic blood flow by a collateral pathway. After that, we performed distal pancreatectomy with en bloc celiac axis resection (DP-CAR). Herein, we report a case of a 68-year-old man with local advanced pancreatic body and tail cancer, who underwent distal pancreatectomy with en bloc celiac axis resection after neoadjuvant chemotherapy and embolus of the common hepatic artery. Since there was a decline of hepatic blood flow, intraoperatively, we therefore performed proper hepatic artery-jejunal artery bypass surgery. We report this rare case with a review of the literature.

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We experienced a case of enteric fever complicated with acute encephalopathy (AE) during a mass food poisoning outbreak in Tokyo. The patient had never traveled abroad. He was admitted to our hospital with the chief complaints of sustained fever and digestive symptoms. He was diagnosed as having enteric fever based on blood and stool culture findings. He developed AE after the initiation of therapy. However, he was discharged without sequela. We analyzed the cytokines in the cerebrospinal fluid (CSF) at the onset of AE, and showed that the interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) levels were elevated. These results suggested that IL-8 and MCP-1 in the CSF might play a role in the pathogenesis of acute S. typhi-associated encephalopathy.

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