An ultrastructural study on cytotoxic effects of mono(2-ethylhexyl) phthalate (MEHP) on testes in Shiba goat in vitro

In this study, the effects of mono(2-ethylhexyl) phthalate (MEHP), one of metabolites of di(2-ethylhexyl) phthalate, on immature Shiba goat testes in vitro were examined. The testes of 2-month-old Shiba goats were cut into smaller pieces, and seeded in medium. At 1, 3, 6 and 9 hr after administration of MEHP at various concentrations (0, 100 nmol ml-1, 1 nmol ml-1, and 1 x 10-3 nmol ml-1, respectively), the specimens were obtained for light and transmission electron microscopic observations. As a result, at 1 hr after exposure to MEHP, the vacuolization and nuclear membrane rupture appeared in Sertoli cells. Such alterations tended to gradually increase in number in timeand dose-dependent manners. Moreover, by MEHP treatment, apoptotic spermatogenic cells (characterized with chromatin condensation, cytoplasm shrinkage without membrane rupture, still functioning cell organelles, and packed cell contents in membrane-bounded bodies), apoptotic Sertoli cells (characterized with nuclear membrane lysis, nuclear condensation), necrotic spermatogenic cells (characterized with swollen and ruptured mitochondria, plasma membrane lysis, spilt cell contents, and chromatin clumps), and necrotic Sertoli cells (characterized with marginated chromatins along the nuclear membrane, ruptured vesicles within the MNB, some swollen and ruptured cell organelles, e.g. mitochondria) could be identified. Conclusively, ultrastructurally the treatment with MEHP at low concentration tends to lead spermatogenic and Sertoli cells to apoptosis, whereas that at high concentration tends to lead spermatogenic and Sertoli cells to necrosis. Thus, the testicular tissue culture is advantageous for screening testicular toxicity of chemicals.

Effects of Intermittent Tepid Blood Cardioplegia in Coronary Artery Bypass Grafting / 日本心臓血管外科学会雑誌

A total of 56 patients undergoing coronary artery bypass grafting were allocated to two groups: the Cold group (28 patients) with cold (4°C) crystalloid cardioplegia and topical ice slush, and the Tepid group (28 patients) with tepid (32°C) blood cardioplegia delivered intermittently antegrade. The two groups were comparable in terms of preoperative New York Heart Association classification, age, gender, and number of grafts. Intraoperatively, tepid blood cardioplegia was associated with a significantly shorter cardiopulmonary bypass time and nearly uniform return of normal sinus rhythm. Cardiac output after bypass was significantly higher than before bypass only in the Tepid group. The absolute peak levels in the myocardial-specific isoenzyme of creatine kinase were higher in the Cold group (70±8IU/<i>l</i>) than in the Tepid group (31±5IU/<i>l</i>). There was a trend toward reduced incidence of perioperative myocardial infarction (0% versus 7.1%) and need for intraaortic balloon pump support (0% versus 3.6%) associated with the use of tepid blood cardioplegia. Our results suggest that intermittent tepid blood cardioplegia is a safe and effective technique for coronary artery bypass grafting.

A Case of Aberrant Right Subclavian Artery Aneurysm and a Review of the Literature / 日本心臓血管外科学会雑誌

Aberrant right subclavian artery is a common congenital anomaly of the aortic arch, with a reported prevalence of approximately 0.5%. However aneurysms of this aberrant vessel are very rare. A 71-year-old man was admitted with cerebral hemorrhage. Chest X-ray revealed an abnormal upper mediastinal shadow. Angiography, computed tomography (CT) scan, and magnetic resonance (MR) imaging revealed an aberrant origin of the right subclavian artery arising as the fourth branch of the aortic arch and crossing the mediastinum from left to right indenting the esophagus posteriorly. The origin of the right subclavian artery was aneurysmal (maximum diameter was 5cm), and this aneurysm did not compress the esophagus. The patient was treated by Dacron patch graft aortoplasty and right subclavian artery reconstruction with the aid of cardiopulmonary bypass and hypothermic selective cerebral perfusion. The postoperative course was uneventful and there were no major complications. The surgical technique is detailed as well as a review of all the cases in the literature.