Novel pyrrolidines in the venom of the ant Monomorium indicum

New 2,5-dialkylpyrrolidines found in the venom of Monomorium indicum include trans-2-butyl-5-(4-pentenyl)pyrrolidine [1], trans-2-butyl-5-(6-heptenyl)pyrrolidine [4], trans-5-(5-hexenyl)-2-(4-pentenyl)pyrrolidine [6], trans-5-(6-heptenyl)-2-(5-hexenyl)pyrrolidine [8], and trans-5-heptyl-2-hexylpyrrolidine [16], whose structures were confirmed by synthesis. The concomitance of five previously reported trans-2,5-dialkyl-pyrrolidines along with small amounts of the cis isomers and N-methyl analogues makes the venom of M. indicum the most qualitatively diverse blend of alkaloids reported from an ant to date. The toxicities to termites of four of these alkaloids were determined.     

Synthesis and teratogenic action of n-hydroxythalidomide

N-Hydroxythalidomide (1d), a potential metabolite of thalidomide (1a), was synthesized from N-phthalyglutaminic acid anhydride (1b) and O-tetrahydropyraline hydroxylamine, followed by deprotection. The teratogenicity of 1d was studied using the Hen's-Egg-Test model which had been found applicable for 1a. 1d was more teratogenic to chicken embryos compared to 1a. The percentage of teratogenic malformations in the 1d groups was 28-46%, whereas the percentage in the 1a groups was 20-23%. The oxygen protected precursor N-hydroxythalidomide (1c) was less teratogenic (11-15%).     

Novel antifungal antibiotics maniwamycins A and B. I. Taxonomy of the producing organism, fermentation, isolation, physico-chemical properties and biological properties

Two antifungal antibiotics maniwamycins A and B were isolated from the culture broth of a strain of actinomycetes, which were classified as Streptomyces prasinopilosus. These antibiotics were isolated by resin absorption and extraction with EtOAc and purified by column chromatography. Both antibiotics were found to be new azoxy substances from their physico-chemical properties. They showed broad antifungal spectra.     

Experimental study on the optimal size of the tricuspid valve annular area on annuloplasty

The optimal size of tricuspid valve annular area (TVAA) by annuloplasty for tricuspid regurgitation remains controversial. Recently, we developed a new measuring system which permits to do real-time measurement of tricuspid valve annular area in anesthetized dogs. Using this system, we studied the optimal size of TVAA by annuloplasty. After the right atrial incision, a metal thread which functions as a sense loop of the electromagnetic fields was stitched along the tricuspid valve annulus (visible juncture of the valve leaflets and the cardiac wall). The drive coil assembly was placed perpendicular to the extension of the long axis of the heart and was directed toward the tricuspid valve region. During control conditions, the maximum TVAA appeared at the onset of ventricular systole. The minimum TVAA appeared during the early ventricular diastolic phase which included the ventricular isovolumic relaxation phase. The maximum TVAA varied in five dogs between 2.2 cm2 and 3.1 cm2, the minimum TVAA also varied between 1.8 cm2 and 2.5 cm2: During regular sinus rhythm, a decrease of TVAA during one cardiac cycle ranged between 11.9% and 22.4% of the maximum size. When TVAA was not decreased by annuloplasty to the minimum area which was observed during cardiac cycle in the control state, the cardiac output and the right atrial pressure remained unchanged, because the ventricular filling was not obstructed. On the other hand, when TVAA was decreased smaller than this minimum area, the cardiac output decreased and the right atrial pressure rose.(ABSTRACT TRUNCATED AT 250 WORDS)     

Digital mammography. ROC studies of the effects of pixel size and unsharp-mask filtering on the detection of subtle microcalcifications

We investigated the spatial resolution requirement and the effect of unsharp-mask filtering on the detectability of subtle microcalcifications in digital mammography. Digital images were obtained by digitizing conventional screen-film mammograms with a 0.1 X 0.1 mm2 pixel size, processed with unsharp masking, and then reconstituted on film with a Fuji image processing/simulation system (Fuji Photo Film Co., Tokyo, Japan). Twenty normal cases and 12 cases with subtle microcalcifications were included. Observer performance experiments were conducted to assess the detectability of subtle microcalcifications in the conventional, the unprocessed digital, and the unsharp-masked mammograms. The observer response data were evaluated using receiver operating characteristic (ROC) and LROC (ROC with localization) analyses. Our results indicate that digital mammograms obtained with 0.1 X 0.1 mm2 pixels provide lower detectability than the conventional screen-film mammograms. The detectability of microcalcifications in the digital mammograms is improved by unsharp-mask filtering; the processed mammograms still provide lower accuracy than the conventional mammograms, however, chiefly because of increased false-positive detection rates for the processed images at each subjective confidence level. Viewing unprocessed digital and unsharp-masked images in pairs resulted in approximately the same detectability as that obtained with the unsharp-masked images alone. However, this result may be influenced by the fact that the same limited viewing time was necessarily divided between the two images.     

Role of immediate versus delayed nephrectomy for failed renal transplants

The role of timing of transplant nephrectomy after renal transplantation has not been well defined. This report compares the morbidity, mortality, and hospitalization costs of 37 patients undergoing transplant nephrectomy within 14 days after graft failure and return to dialysis, with 31 patients undergoing delayed transplant nephrectomy (less than 14 days after graft failure and return to dialysis). This analysis revealed that there were no significant (P greater than .05) differences in patient morbidity and mortality between these groups. There was, however, a substantial increase (P less than .05) in the cost of hospitalization in the delayed nephrectomy group. For this reason, we recommend early nephrectomy after renal transplant failure in order to minimize the cost of health care for these patients undergoing failed cadaver donor transplant nephrectomy.     

346. Die bedeutung von stenosen an gefä\verzweigungen. eine experimentelle untersuchung an der femoralisgabel unter besonderer berücksichtigung der indikation zur profundaplastik

Zusammenfassung In einem pulsatil mit Kochsalz durchströmten Modell der Femoralisgabel wurden Flussmessungen und Druckgradienten für Flussmengen von 170 bis 860 ml/min bei peripheren Widerständen von 232 bis 25 792 dyn s cm^–5 über dem Superficialis- und Profundaabgang bei Stenosen von 1 cm Länge und Querschnittsverminderungen von 0% bis 100% gemessen. Bei grossen Flussmengen (800–860 ml/min) und kleinem peripheren Widerstand (<640 dyn s cm^–5) lag die kritische Stenose am Profundaabgang bei 4,1 mm Durchmesser, für hohe periphere Widerstände (> 5 072 dyn s cm^–5) bei 2,6 mm; bei kleinen Flussmengen (<400 ml/min) betrug der kritische Durchmesser 1,8 mm. Der nicht stenosierte Profundaabgang stellte für keine der Versuchsbedingungen ein strömungsdynamisches Hindernis dar.     

A study of the use of intravenous cannulas for medical emergencies in Newham--implications for financial savings

A study of intravenous (i.v.) cannula usage for medical emergencies admitted to hospitals in the Newham Health District was undertaken during two defined periods (24 and 35 days). Almost half the cannulas inserted (47%) were not flushed following an initial bolus injection of heparinized saline. The duration that cannulas remained in a vein ranged from 24 hours to 8 days (median 2 days) and inflammation around the cannula site was related to the length of time since insertion but unrelated to whether the cannula was flushed regularly or to the type of fluid used. Our findings indicate a substantial wastage of i.v. cannulas due to difficulties with insertion and suggest that isotonic saline, without heparin, is effective in maintaining cannula patency for 48 hours. It is concluded that these findings are not unique to the Newham Health District and worthwhile financial savings should be achieved throughout the NHS if clinicians reconsider the indications and use of i.v. cannulas for their patients.