Prostaglandins have been shown to contribute to the pathogenesis, progression and exacerbation of ischemic heart disease. Prostaglandins have also reported to contribute to the arrhythmogenesis of lethal arrhythmias during ischemia and reperfusion. In this review article, The electrophysiologic effects of prostacyclin, its stable analogues, thromboxane A₂ and its stable analogue were reviewed, and described the in vitro effects of a stable analogue of prostaglandin, and a stable analogue of thromboxane A₂ in our laboratory. Finally, the electrophysiologic and metabolic effects of a thromboxane A₂ synthetase inhibitor on the coronary artery occlusion/reperfusion model were studied in our laboratory. The prostacyclin analogue shortened the action potential duration in a normal Tyrode′s solution, and shifted the Vmax - resting membrane potential curve rightward. The TXA₂ analogue did not exhibit any electrophysiologic effects on the normal, high K⁺, and simulated ischemia conditions. Intracoronary administration of the TXA₂ analogue led to marked surface and epicardial ECG ST segment elevation and the subsequent development of ventricular tachycardia. The thromboxane A₂ synthetase inhibitor elicited significant reduction of ventricular premature contractions and tended to reduce reperfusion-induced ventricular fibrillation. The rise in extracellular K⁺ concentration of the ischemic myocardium was markedly decreased in the thromboxane A₂ synthetase inhibitortreated group. Therefore, prostacyclin may be antiarrhythmic through its direct electrophysiologic effects, i.e., recovery of Vmax leading to improvement of conduction delay during ischemia, and thromboxane A₂ may be arrhythmogenic not through its direct electrophysiologic effects on the ischemic myocardium, but through exacerbation of ischemia due to its potent vaso-constrictive effects.

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Background: Flipped classroom methodologies have gained popularity and undergone much research scrutiny in recent years. However, there have been no studies examining the effects of flipping an English, first-year, basic medical history taking, oral communication skills course in Japan. Methods: A 1-year prospective cohort of students (n = 135) enrolled in an English, basic medical history taking course (30 hours) was taught using a flipped approach. A historical cohort of students (n = 128) was taught using a more conventional task-based communicative approach (45 hours) for comparison. Baseline metrics indicated that there was adequate similarity for comparison between the two groups. Performance examination scores were analyzed to assess effectiveness in 4 categories: Spoken English Proficiency (SEP); Communication and Interpersonal Skills (CIS); Integrated Clinical Encounter (ICE); Comprehension (Comp.). Results: The overall average examination score increased from 67.5 ± 1.5% (mean ± SE) in 2014 to 77.5 ± 1.5% in 2015 (mean difference between the groups, 9.6%; [95 percent CI, 5.5% to 13.7%], P ⟨ .001) indicating a significant improvement in student performance. Largest gains were observed in SEP and CIS and there were no significant changes in the ICE and Comp. categories. Conclusion: It appears that students performed significantly better in a basic history taking examination with a simulated patient in English after having been taught using the “Flipped Classroom” method, despite having had 15 fewer classroom hours. Therefore, it is worth considering this innovative methodology as a means to improve educational effectiveness.

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ST-T alternans during ischemia is associated with ventricular arrhythmias and reflects primary changes in repolarization, and changes secondary to 2:1 conduction block. We studied the effect of pinacidil, an ATP-sensitive K⁺ channel activator, on the incidence of ST-T alternans during ischemia. K⁺- and pH-sensitive electrodes and unipolar and bipolar electrodes were inserted into the midmyocardium in 9 open-chested pigs. Transmembrane action potentials were recorded from the epicardial surface. The carotid artery was shunted to the left anterior descending artery via a roller pump, and 25 μM pinacidil was infused. Prior to pinacidil administration, ST-T alternans occurred in all 9 pigs during control ischemia, at a mean onset time of 4 minutes 23 seconds ± 22 seconds. After pinacidil infusion, no ST-T alternans occurred during the 8-minute ischemic period. Furthermore, after pinacidil infusion, the final rise in extracellular K⁺ ([K⁺]_e) and the fall in extracellular pH (pH_e) were similar to the those at the onset of ST-T alternans under control conditions ([K⁺]_e : 7.6 ± 0.9 vs. 6.9 ± 0.9 mM; pH_e: 7.08 ± 0.78 vs. 7.05 ± 0.18). Activation delay was also similar with pinacidil administration compared with that at the onset of ST-T alternans, under the control condition (27 ± 18 ms vs. 34 ± 24 ms). With pinacidil, the action potential duration after 8 minutes of ischemia was decreased by 50% (from 250 ± 36 ms to 127 ± 15 ms). The complete suppression of ST-T alternans by pinacidil may reflect an increase in the diastolic interval.

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Background: Both contact force (CF)-guided radiofrequency ablation (RFA) based pulmonary vein isolation (PVI) and second-generation cryoballoon ablation (CBA) based PVI may improve the procedural outcome. However, the clinical outcome after RFA- and CBA-based PVI remains unclear. Adenosine or adenosine triphosphate (ATP) administration after PVI is useful to detect dormant PV conduction (DC) after the ablation procedure, and the presence of DC has been shown to be related to AF recurrence. Methods: Out of 100 patients with paroxysmal AF (PAF), 50 underwent CF-guided PVI (25-30 W, 30 sec for each ablation: CF-RFA group), and the remaining 50 patients underwent cryoballoon ablation-based PVI (3 min cooling + 2 min bonus cooling for each PV: CBA group). Thirty minutes after PVI, a 30-mg bolus of ATP was administered. We compared the success rate of PVI, and incidence of DC after PVI between the CF-RFA and CBA groups. Results: The subsequent response was assessed for each vein using a ring catheter. In the CBA group, 180 (90%) of 200 PVs were isolated and 20 PVs (10%) (2 left superior PV (LSPV), 3 left inferior PV (LIPV), 4 right superior PV (RSPV), 11 right inferior PV (RIPV) from 14 of 50 patients (28%) required additional RFA because of residual potential at the PV or PV antra. After a waiting period of 30 min after the last energy application, acute PV reconduction was observed spontaneously in 13 PVs (6.5%) (6 LSPV, 3 LIPV, 4 RSPV) from 12 patients (24%) in the CF-RFA group. The DC sites provoked by ATP were 13 PVs (6.5%) (5 LSPV, 3 LIPV, 2 RSPV, 3 RIPV) from 8 patients (16%) in the CF-RFA group, compared with 9 PVs (4.5%) (2 LSPV, 4 LIPV, 1 RSPV, 2 RIPV) from 9 CBA patients (18%) (P = 1.000). AF recurred in 6/50 (12%) in both the CF-RFA and CBA groups at 1 year after the ablation (P = 1.000). Conclusions: There was no significant difference in the incidence of DC after PVI and the 12-month AF-free rate between the second-generation CBA- and CF-based RFA.

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We present a case of an 8-month-old boy who was born as an extremely low birth weight infant (ELBWI) and had a history of pulmonary hypertension (PH) associated with chronic lung disease (CLD). When the patient appeared for a regularly scheduled outpatient visit, he developed a PH crisis which required resuscitation. After we began to treat him with pulmonary artery dilating agents, he recovered from the PH crisis, and we discharged him from hospital with home oxygen therapy. ELBWIs are often complicated with CLD. Moreover, some of those cases with severe CLD are complicated with PH and can have a poor prognosis. Because routine echocardiograph can miss the development of PH, appropriate risk evaluation and attentive follow-up are required.

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A 1-year-old girl presented to our department with a skin and soft tissue infection (SSTI) accompanied by anabscess. This was a recurrent infection that also affected other family members. Samples were obtained from the whole family and bacterial culturing identified methicillin-resistant Staphylococcus aureus (MRSA) as the causative agent in all cases. Further identification using genetic analysis revealed it was a USA300 clone. The clinical procedure of decolonization was offered to the family as a preventative and therapeutic measure. In all of the cases, except for the child′s mother, decolonization was effective, and no recurrence of infection occurred over a 1 year period. We speculated that the recurrent SSTI in the child′s mother was due to poor control of atopic dermatitis.

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The number of Japanese tuberculosis patients has been declining; however, with the development of transportation and the rising number of foreign workers and tourists in Japan, we are now seeing an annual increase in the number of tuberculosis incidence among foreign patients. We recently experienced a case with a newborn infant born to a mother of foreign nationality with latent tuberculosis infection, and a father, also of foreign nationality, who was diagnosed with tuberculosis. In consideration of the fact that we may be seeing more similar cases in the future, we believe that there is a need to once again review and reconfirm how to cope with this situation.

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Hand-assisted laparoscopic surgery (HALS) has been applied to various diseases since the report of Hand-Assisted Laparoscopic Splenectomy by Kusminsky et al. in 1995. Herein, we report a case of perforation of a duodenal ulcer that required Omental Implantation Repair using HALS, with no complication. The patient was a 43-year-old man. In January 2016, he complained of an epigastrium ache. He called an ambulance and came to our hospital. The diagnosis was perforation of the upper gastrointestinal tract. We performed an emergency operation. We used a Gel Port^® and inserted 12mm trocar under the umbilicus and 5mm at the left abdomen, 5mm and 12mm at the right abdomen. After washing the intra-abdominal cavity, we performed Omental Implantation Repair using a small incision. He was discharged from the Hospital after 14 days with no complications. HALS not only provides a sense of touch in open surgery but also provides an extended effect in Laparoscopic surgery. Therefore, HALS is useful in the operation for upper gastrointestinal tract perforation.

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We describe our experiences with two Cases of torsion of the gallbladder, which required emergency open cholecystectomy. In both cases, ultrasonography showed swelling of the gallbladder with thickened walls that were suspected as being due to acute cholecystitis. However, computed tomography scans of the abdomen revealed that the gallbladder had shifted caudally. Thus, we diagnosed these cases as torsion of the gall bladder. While this disease is relatively rare, the symptoms are not unique. Emergency operation is necessary when torsion of the gallbladder is suspected. Thus, it should be always considered in the differential diagnosis of acute cholecystitis.

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A 16-month-old girl was transported to the emergency room at our hospital with severe liver dysfunction. We diagnosed acute hepatic failure with five of the six main symptoms of Kawasaki disease, in addition to cervical lymphadenopathy. Therefore we considered the coexistence of Kawasaki disease. We promptly initiated multidisciplinary treatment, including plasma exchange and continuous hemodiafiltration, and finally transferred the patient to a hospital capable of performing living donor liver transplantation. Living donor liver transplantation was performed and membranous desquamation of the toes was observed after surgery. Although liver dysfunction often complicates in the acute phase of Kawasaki disease, there has been no report of any association with acute hepatic failure. Human herpes virus 6 was detected by PCR examination. However, the patient had already experienced a clinical course of exanthem subitum. The pathological findings of liver biopsy were consistent with acute hepatic failure. It is necessary to reconsider the relationship between severe liver dysfunction and Kawasaki disease.

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