New marine diterpenoids from the Okinawan soft coral Clavularia koellikeri

Chemical investigation of the Okinawan soft coral Clavularia koellikeri resulted in the isolation of two new cembrane diterpenoids (1 and 2) and one new dollabelane diterpenoid, 3. Their structures were determined on the basis of the results of spectroscopic analysis. Compounds 1 and 3 were examined for in vitro growth-inhibition effects toward tumor cells.     

Recurrent low output syndrome after the weaning from mechanical circulatory support for postcardiotomy cardiogenic shock

We reviewed the cases of recurrent low output syndrome (LOS) after the weaning from mechanical circulatory support for postcardiotomy cardiogenic shock. Twelve patients were divide into 2 groups according to whether low output syndrome recurred or not, consisting of a recurrent low output syndrome (+) group [re-LOS (+) group, n = 6] and a recurrent low output syndrome (-) group [re-LOS (-) group, n = 6]. Between 2 groups, there was no statistical difference in preoperative left ventricular ejection fraction (LVEF), aortic closs-clamping time and cardiac index at the weaning from mechanical circulatory support. Only the LVEF at the weaning in the re-LOS (+) group was significantly less than that in the re-LOS (-) group (0.39 +/- 0.08 vs 0.62 +/- 0.19, p < 0.05). All patients in the re-LOS (-) group survived to discharge, while in the re-LOS (+) group, although 3 patients were re-supported by intra-aortic balloon pumping, 4 of 6 patients died of multiple organ failure and 2 survivors were in New York Heart Association class III. The results suggest that the key to survive to discharge after the weaning from mechanical circulatory support is whether the cardiac contraction could recover or not.     

Examination of dose verification in intensity modulated radiation therapy (IMRT) treatment planning using averaging dose in chamber volume

Since the year 2000, our hospital has been equipped with an intensity modulated radiation therapy (IMRT) facility. Before IMRT is administered, the absorbed dose is measured by the ionization chamber to provide verification for the IMRT procedure. In utilizing the current point dose evaluation, large discrepancies have been experienced when the measured dose is compared with the calculated dose. This discrepancy is due to the lack of uniformity in IMRT irradiation in comparison with that of the present method of dose distribution. In order to reduce the margin of error, the average dose of the ionization chamber calculated on a dose-volume histogram was compared with the measured dose. As a result, the margin of error was minimized to <2% in uniform areas and <4% in non-uniform areas.     

Central suppressive effect of octreotide on the hyperglycemic response to 2-deoxy-D-glucose injection or cold-swim stress in awake rats: possible mediation role of hypothalamic noradrenergic drive

Somatostatin (SRIH) and its analog have been reported to act within the central nervous system to suppress the hyperglycemic response to a variety of neural stimuli. On the other hand, the hyperglycemic response to 2-deoxy-D-glucose (2-DG) injection or cold-swim stress is well demonstrated to be closely associated with an increase in hypothalamic noradrenergic neuronal activity (NNA). To evaluate whether the suppression of the hypothalamic NNA response could be involved in the central mechanism whereby a SRIH analog inhibits the hyperglycemic response, octreotide, a clinically used long-acting octapeptide SRIH analog, was administered into the third cerebral ventricle of awake rats prior to the intraperitoneal injection of 2-DG or cold-swim stress. Hypothalamic noradrenaline (NA) and its neuronal metabolite, 3,4-dihydroxyphenylethyleneglycol (DHPG), were analyzed, and the ratio of DHPG to NA was used as an index of NNA. Intracerebroventricular (i.c.v.) pretreatment with octreotide suppressed the 2-DG-induced increase in hypothalamic NNA, accompanied by the inhibition of the serum glucose, NA and adrenaline responses. This suppressive effect of octreotide was dose-dependent. Similarly, i.c.v. pretreatment with octreotide prevented the hypothalamic NNA response to cold-swim stress, accompanied by a blockade of the increases in serum glucose, NA and adrenaline. A close relationship between hypothalamic NNA and serum glucose emerged from these studies. Intraperitoneal pretreatment with octreotide had no significant effect on the hyperglycemic or hypothalamic NNA response to 2-DG injection. These findings suggest that the inhibitory effect of octreotide on the hypothalamic NNA response to 2-DG injection or cold-swim stress is associated with the simultaneous suppression of the hyperglycemic response. Supporting the concept that hypothalamic NNA contributes to the modulation of blood glucose in stressful conditions, it is suggested that the suppression of the hypothalamic NNA response is, at least in part, involved in the central mechanism by which octreotide inhibits the hyperglycemic response to 2-DG injection or cold-swim stress.