Histochemical changes in host tissues from Plasmodium cynomolgi B infected rhesus monkey (Macaca mulatta).

Plasmodium cynomolgi B has been used to infect the rhesus monkey to study the histochemical changes (lipid infiltration, glycogen, protein, DNA and RNA) in liver, kidney and spleen during early (exoerythrocytic) and late (chronic) stages of malarial infection. Infected liver showed significant lipid infiltration during exoerythrocytic and erythrocytic (acute phase) stage of infection. Kidney showed lipid deposition during acute phase of infection while spleen sections were negative for lipid depositions. As a result of malarial infection there was significant depletion of glycogen in liver during exoerythrocytic stage of infection. Glycogen content increased in liver and kidney during erythrocytic stage of infection. The spleen which is the main target of immunopathology in malaria showed no change in glycogen content. During exoerythrocytic phase host tissue organs showed no change in protein and nucleic acids while erythrocytic phase showed slightly increased proteins in liver and kidney. Nucleic acids became decreased in liver and spleen during erythrocytic phase of infection. The parasite used in this study has a defined prepatent period, can be cyclically passaged with ease and non fatal in nature.

Development and initial evaluation of a vas deferens valve.

In 17 cases of vasectomy, the external diameter of vas deferens was found to be 2.07 +/- .27 mm (Mean +/- S.D.) with a range from 1.7 to 2.8 mm. The internal diameters were 0.93 +/- 0.13 at 5 g and 1.24 +/- 0.16 mm at 100 g insertion force applied to the measuring cone, with lumen ranges from 0.7 to 1.2 and 1.0 to 1.7 mm, respectively. The left-right variations in the same inidividual were of a similar order as between different individuals. Measurements in 6-10 kg rhesus monkeys revealed an internal vas diameter around 0.6 mm with the measuring cone only eased in. At considerably high pressure the vas could be distended to show an internal diameter around 1 mm. The external diameters ranged from 1.5 to 2 mm. Local application to the vas in vivo or in vitro of alpha or beta adrenergic blocking agents, and sodium nitrate had no appreciable effects on the diameters. Three types of valves were developed and tested. The tap-like and the rotary valves were not satisfactorily leak-proof. But the valve with stop-cock mechanism was found to be satisfactory. It was further tested by examining the ejaculate obtained by the method of electro-ejaculation after implanting the valve in the monkey vas. The stop-cock valve is being proposed as a working model for producing reversible vas-occlusion.