Biomedical subjects

C Weerasinghe

Publications and source records attributed to C Weerasinghe.

5 recordsLinked to original sources

PubMed1998

An improved algorithm for rotational motion artifact suppression in MRI.

An improved algorithm for planar rotational motion artifact suppression in standard two-dimensional Fourier transform magnetic resonance images is presented. It is shown that interpolation of acquired view data on the uncorrupted k-space create data overlap and void regions. We present a method of managing overlap data regions, using weighted averaging of redundant data. The weights are assigned according to a priority ranking based on the minimum distance between the data set and the k-space grid points. An iterative estimation technique for filling the data void regions, using projections onto convex sets (POCS), is also described. The method has been successfully tested using computer simulations.

Algorithms↗

PubMed1989

Comparison between Sri Lankan and Australian strains of Babesia bovis in the vaccination of imported cattle in Sri Lanka.

A Sri Lankan strain of Babesia bovis (designated A strain) was isolated from larval ticks and prepared for use as vaccine by syringe-passage in 20 splenectomised calves followed by irradiation. The A strain and a vaccine strain of Babesia bovis (designated K strain) brought in frozen form from Australia were used to vaccinate 37 susceptible bulls imported from southern Australia. Rectal temperatures, packed cell volumes, parasitaemias and overt clinical signs were monitored for three weeks following vaccination. The results indicated that the A strain was slightly more virulent than the K strain but suitable for the vaccination of well-supervised cattle.

Animals↗

PubMed1989

A double-blind comparative study: amineptine (Survector 100) versus imipramine.

The aim of the study was to compare the antidepressant effects of amineptine with imipramine in depressive illness. According to the DSM-III criteria, 33 patients diagnosed as having depressive illnesses were given either imipramine or amineptine, 50-100 mg and 100-200 mg, respectively, per day on a double-blind basis over a period of 2 months. Both groups presented steady improvement of the symptoms of depression during treatment, as scored on the Hamilton and Montgomery and Asberg Depression Rating Scales and Clinical Global Impression Scale. Amineptine produced fewer anticholinergic effects than imipramine. The results show that amineptine, as well as imipramine, is well suited for treating depressed patients.

Adult↗

PubMed1979

Effect of synthetic C-terminal fragments of hGH on glucose oxidation by isolated islets.

The effect of polypeptides containing the human growth hormone sequence 177--191 on the glucose metabolism of isolated islets of Langerhans has been investigated. It has been found that such peptides accelerate the incorporation of hydrogen at carbon atom 5 into water while accelerating the flux (1-14C oxidation) through the pentose phosphate shunt and inhibiting the oxidation of [6-14C]glucose. The latter inhibition was found not to be due to inhibition of the pyruvate dehydrogenase complex, and it was further found that the previously demonstrated potentiation of glucose-induced insulin release by the peptides was independent of energy provision because none of the glyceraldehyde, pyruvate, or leucine could substitute for glucose. In view of the fact that the insulinogogue effect of this peptide is to potentiate the glucose stimulatory effect on islets, these phenomena may well be unrelated.

Animals↗

PubMed1978

Effect of synthetic C-terminal fragments of hGH on insulin release by isolated islets.

Synthetic fragments representing the C-terminal end of the growth hormone molecule have been tested for their direct in vitro effects on insulin release by isolated rat islets of Langerhans. hGH 177-191 caused a dose-related potentiation of glucose-induced insulin release, whereas the peptide by itself caused no stimulation of insulin release from the islets. The rate curves constructed for insulin secretion as a function of extracellular glucose concentration showed that the Km for glucose is not altered in the presence of the peptide, but that the Vmax of secretion is increased. Significant potentiation of insulin release by the peptide was seen only at high extracellular concentrations of glucose. Measurement of cAMP levels in islets showed that the peptide caused no significant alteration of cAMP levels while still potentiating insulin release. It was therefore concluded that the mechanism of potentiation of insulin release by the peptide may be independent of the changes in cAMP levels in islets. hGH 172-191, too, caused potentiation of glucose-stimulated insulin release from islets, whereas hGH 179-191 was not active in this report.

Animals↗