Differences in cloning and sub-cloning success rates in four stocks of Trypanosoma evansi and variation in suramin resistance of the clones

Four Trypanosoma evansi stocks with sensitivity to suramin in mice ranging from 0.05 to 160 mg kg-1 were cloned and sub-cloned and the sensitivity of the clones determined. The results suggest that it is easier to clone and sub-clone trypanosome stocks which are sensitive to suramin than those that are resistant to the action of the drug. The clones obtained from the four stocks had sensitivities to suramin which were similar to or different from the parent stocks. These results are important in view of the development of resistance for, in the presence of suramin, these resistant yet heterogeneous populations would provide the material from which selective processes could operate. These observations also suggest that the maintenance and spread of suramin-resistant trypanosomes might be curtailed by their comparative inability to establish themselves in a new host.     

Effects of citidine diphosphocholine (citicholine) and phospholipids on the elastic properties of the lung and on the physico-chemical properties of the irrigation liquid]

The chemical composition of yeast cells of Oidiodendron kalrai was analyzed and is expressed as percent dry weight. Cultures were grown in tryptone broth and in a liquid synthetic medium containing ammonium salts as a nitrogen source. After 48 h, carbohydrate levels were higher in the synthetic medium, but lipid levels were lower, Deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein contents did not differ significantly in the two media. The chemical components were also studied at different stages of growth. DNA remained relatively constant, but other components varied with the age of culture. The RNA was 6.6% at 18 h and declined rapidly to 5% by 24 h and remained constant, An initial protein content of 23% at 18 h increased rapidly to 37% by 48 h and gradually declined to 30% by day 10. The lipid content of 33% at 18 h decreased over the entire growth period to 10% by day 10. An initial carbohydrate level of 30% increased to a maximum of 54% by day 5 and then declined.     

Histomorphologic assessment of the effectiveness of anesthesia during tooth preparation

The efficacy of conduction anesthesia with 2% solutions of novocain, celnovocain, trimecain, lidocain during the preparation of teeth for metal crowns was studied in experiments on 16 dogs by neurohistological and histochemical examination of the Gasserian and superior cervical ganglions, the nodose ganglion, teeth and pericoronal tissues. It was established that in terms of the degree of anesthesia efficacy increase, the test anesthetics can be arranged as follows: novocain, celnovocain, trimecain, lidocain.     

A G protein gamma subunit-like domain shared between RGS11 and other RGS proteins specifies binding to Gbeta5 subunits

Regulators of G protein signaling (RGS) proteins act as GTPase-activating proteins (GAPs) toward the alpha subunits of heterotrimeric, signal-transducing G proteins. RGS11 contains a G protein gamma subunit-like (GGL) domain between its Dishevelled/Egl-10/Pleckstrin and RGS domains. GGL domains are also found in RGS6, RGS7, RGS9, and the Caenorhabditis elegans protein EGL-10. Coexpression of RGS11 with different Gbeta subunits reveals specific interaction between RGS11 and Gbeta5. The expression of mRNA for RGS11 and Gbeta5 in human tissues overlaps. The Gbeta5/RGS11 heterodimer acts as a GAP on Galphao, apparently selectively. RGS proteins that contain GGL domains appear to act as GAPs for Galpha proteins and form complexes with specific Gbeta subunits, adding to the combinatorial complexity of G protein-mediated signaling pathways.     

Maxillary sinus augmentation in the non-human primate: a comparative radiographic and histologic study between recombinant human osteogenic protein-1 and natural bone mineral

The posterior maxilla has traditionally been one of the most difficult areas to successfully place dental implants due to poor bone quality and close approximation to the maxillary sinus. Sinus augmentation procedures have become a viable means of assuring adequate bone for the placement of dental implants in this area. However, with the techniques currently employed, a considerable variation in the quality of bone attained with the sinus augmentation procedure exists. The purpose of this in vivo study was to evaluate the healing response and bone formation stimulated by 3 doses of recombinant human osteogenic protein-1 (rhOP-1), 0.25, 0.6, and 2.5 mg OP-1 per gram of collagen matrix; natural bone mineral; or collagen matrix alone (control) placed in the maxillary sinus of adult chimpanzees. Results were assessed using clinical, histologic, and radiographic techniques. Radiographic analysis of the computed tomography scans taken at 1 week, and 2.5, 4.5, and 6.5 months revealed a more rapid mineralization with the 2.5 mg OP-1/g collagen matrix and natural bone mineral treatment groups. The incremental bone mineral density (BMD) increase for these 2 treatments from 1 week to 2.5 months was over 2.5 times the increase found with the collagen matrix alone; these 2 treatments also had a higher BMD at the most superior slices evaluated when compared to the other 3 groups. Biopsy specimens were taken at 3.5, 5.5, and 7.5 months and for all 5 treatment groups bone formation was observed at all time points in the majority of the specimens. At 7.5 months the 2.5 and 0.6 mg OP-1/g collagen matrix treatment groups had an increase in the percent bone area when compared to the matrix alone control. In conclusion, these results demonstrate that sinus augmentation with natural bone mineral or 2.5 mg OP-1/g collagen matrix induce comparable radiographic and histologic evidence of bone formation and that both of these treatments performed superior to the control group of collagen matrix alone based upon all methods of evaluation.