Dipetalonema viteae in Mastomys natalensis: effect of pregnancy and lactation on establishment and course of infection

The susceptibility of hosts to filarial infection during pregnancy and lactation was studied using Dipetalonema viteae in Mastomys natalensis as working model. Though no difference in prepatency could be observed yet significantly higher density of microfilaraemia than controls was detected in both pregnant and lactating groups. Extended duration of patency was also found in both pregnant and lactating animals. On autopsy, animals exposed at the time of pregnancy or lactation revealed significantly higher recovery of adult worms as compared to normal controls. Thus pregnancy and/or lactation may lead to higher density and duration of microfilaraemia and enhanced establishment of adult worms in female mastomys which are otherwise less susceptible to filarial infection.

Studies in potential filaricides. 18. Synthesis of 2,2'-disubstituted 5,5'-dibenzimidazolyl ketones and related compounds as potential anthelmintics

A series of 2,2'-disubstituted 5,5'-dibenzimidazolyl ketones and related compounds have been synthesized of which 2,2'-bis(carbomethoxyamino)-5,5'-dibenzimidazolyl ketone exhibited a broad spectrum of anthelmintic activity in experimental animals. At doses of 10-50 mg/kg given intraperitoneally, 5 killed 100% of the adult worms of Litomosoides carinii, Dipetalonema viteae, and Brugia malayi. By the oral route the macrofilaricidal efficacy of 5 was 97-100% at 100-200 mg/kg X 5 days. The treated animals showed gradual disappearance of microfilariae and before autopsy they became amicrofilariaemic. Some of the compounds also showed 100% efficacy against the human hookworms and tapeworm, Ancylostoma ceylanicum in hamsters, and Hymenolepis nana in rats at a single oral dose of 50-250 mg/kg. Compound 5 was also effective against Syphacia obvelata in mice at a single oral dose of 100 mg/kg and was found to be well tolerated by mice up to an oral dose of 2500 mg/kg.

Synthesis and anthelmintic activity of 5(6)-(benzimidazol-2-ylcarbamoyl) and (4-substituted piperazin-1-yl)benzimidazoles

The synthesis of alkyl 5(6)-(benzimidazol-2-ylcarbamoyl)benzimidazole-2-carbamates (6, 7), and alkyl 5(6)-(4-substituted piperazin-1-yl)benzimidazole-2-carbamates (31-40) has been carried out. When the compounds were tested for their anthelmintic activity against Ancylostoma ceylanicum in hamsters, Hymenolepis nana in rats, Litomosoides carinii in cotton rats, and Dipetalonema viteae in Mastomys natalensis, methyl 5(6)-(4-benzoylpiperazin-1-yl)benzimidazole-2-carbamate (31), methyl 5(6)-[4-(2-furoyl)piperazin-1-yl]benzimidazole-2-carbamate and methyl 5(6)-[4-[(diethylamino)carbonyl]piperazin-1-yl]benzimidazole- -2-carbamate (36) showed 100% elimination of tapeworms H. nana at three oral doses of 100-250 mg/kg. Compounds 34 and 36 also killed the microfilariae and adult worms of L. carinii in cotton rats at an intraperitoneal dose of 30 mg/kg given for 5 days.

Protein kinases in different life stages of Brugia malayi and other filarial worms

The investigation of protein kinase activity in different life stages of a few filarial worms indicates the presence of different protein kinases and of dissimilarities between the distribution pattern of these enzymes during the development. Phosvitin turned out to be the preferred exogenous acceptor protein, when homogenates of adults of Brugia malayi, Dipetalonema viteae, Setaria cervi and Litomosoides carinii were used as source of enzyme. In contrast to adults the L3-larval and the microfilarial stages demonstrated much lower phosvitin phosphorylating activity and the preference for acidic and basic proteins as phosphate acceptors was about equal. The occurrence of cyclic AMP-dependent protein kinase was established for adults of B. malayi.

Studies of potential filaricides: Part 14--Activity of 1-iso-butoxycarbonyl-4-methylpiperazine against experimental filariasis

The synthesis and filaricidal activity of 1-iso-butoxycarbonyl-4-methylpiperazine against Litomosoides carinii in Sigmodon hispidus and Dipetalonema viteae in Mastomys natalensis is reported. At an intraperitoneal or oral dose of 3 mg/kg given for 6 days, the compound removed 91% of the circulating microfilariae but had no effect on adult L. carinii. However, it killed all microfilariae and adults of D. viteae at a subcutaneous dose of 50 mg/kg given for 6 days. The compound also possessed chemoprophylactic activity against the larvae of L. carinii and D. viteae at a dose of 30 and 50 mg/kg respectively.

Uptake of adenosine 3',5'-cyclic monophosphate and isoproterenol by filarial parasites

The filarial parasites Litomosoides carinii and Dipetalonema viteae both show transcuticular uptake of adenosine 3',5'-cyclic monophosphate but isoproterenol is taken up by D. viteae only. The importance of this difference is discussed from the point of view of metabolic regulation. Inhibition of uptake by lectins indicates the involvement of surface sugar moieties in the transport processes.

Lysosomal enzyme in Mastomys natalensis during Dipetalonema viteae infection

Activities of certain acid hydrolases (viz. acid phosphatase, beta-glucosidase, beta-galactosidase, N-acetyl-beta-D-glucosaminidase and cathepsine) of post mitochondrial fraction of liver and spleen were studied during the course of Dipetalonema viteae infection in Mastomys natalensis. The values are significantly higher from prepatent to patent phase of infection as compared with normal animals. However, a decrease in the activity of hepatic acid phosphatase and N-acetyl-beta-D-glucosaminidase was noticed in latent phase of infection while a several fold increase in the activity of these enzymes was observed in splenic tissue when there were no detectable microfilariae (mf) in peripheral circulation. The results suggest that lysosomal acid hydrolases which constitute an important component of resistance may be activated by mf products through the sensitized cells of RE system.

Glycogen pattern in natural and alternate hosts infected with Litomosoides carinii

Litomosoides carinii infection causes a decrease in liver glycogen levels in the albino rat, an alternate host, but not in its natural host, the cotton-rat. In the albino rat the primary infection is rejected by about 120 days after infection whereas in the cotton-rat rejection does not occur. Consequently, the drop in hepatic glycogen levels in the albino rat has some correlation with the immune status of the host.

Manchester knee arthroplasty

The results of fifty-one Manchester knee arthroplasties in forty-one patients are reviewed and discussed. Excellent and good results were obtained in 85.4 per cent of arthroplasties. Varus and valgus deformity can be corrected and stability preserved or restored. Complications occurred in only twelve patients but resolved in all except one.