Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042961 (volvulus)
 4,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In view of the promise shown by temperate simuliids for laboratory colonization, the ability of Simulium ornatum and S. lineatum to support the development of Onchocerca volvulus was investigated. An injection technique is described for the introduction of O. volvulus microfilariae from a chimpanzee into female simuliids in the absence of a bloodmeal. RPMI 1640 medium, with penicillin, streptomycin and foetal calf serum, proved satisfactory as an inoculation medium. Third stage larvae were obtained in both S. ornatum and S. lineatum after seven days at 27 degrees C. The rate of development of the parasite in S. ornatum is recorded.
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PMID:The development of Onchocerca volvulus in two temperate blackfly species, Simulium ornatum Meigen and Simulium lineatum Meigen. 53 57

The effects of co-culture with monkey kidney cells (LLCMK2), cell-conditioned medium and decreased atmospheric oxygen on the in vitro molting and viability of infective stage larvae (L3) of Onchocerca lienalis and O. volvulus were examined. O. lienalis L3 were cultured in an RPMI 1640-based medium in the presence of an LLCMK2 cell monolayer or in medium which had been conditioned for three days by cells. In paired experiments cell conditioned medium alone in 95% air/5% CO2 produced molting levels of 54 +/- 14% which increased to 67 +/- 20% in treatments cultured under decreased oxygen; this value equalled the level of molting of worms cocultured with LLCMK2 cells. Worm survival in the three environments was similar. In seven additional experiments using O. lienalis (n = 186), overall levels of 74 +/- 12 percent molting and 75 +/- 7% viability on days 21-33 were obtained. Worms increased in length from 503 +/- 50 mu as L3 to 638 +/- 74 mu as L4 on day 21 (p = 0.0001, n = 42-44). Ultrastructural comparison of an in vitro derived L4, (39 days in culture) vs a vector-derived L3 revealed fewer annulations and decreased osmiophilia on the epicuticle of the L4 while the hypodermis showed increased morphogenetic definition. O. volvulus molted at an average rate of 74% (n = 40) with a mean viability on day 28 of 95%. L3 increased in length from a mean of 635 +/- 50 mu to 775 +/- 45 mu as L4 on day 28 (p = 0.0001). Larvae of both species were cultured under these conditions for periods of time exceeding 100 days.
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PMID:The use of cell-conditioned medium for the in vitro culture of Onchocerca spp. larvae (Nematoda: Filarioidea). 233 42

Uptake and macrofilaricidal effects of chloroquine (CQ) and other aminoquinolines were found to be highly pH dependent in Brugia pahangi, Acanthocheilonema viteae, Onchocerca volvulus, and Dirofilaria immitis. Using [3H]CQ, it was found that all of the parasites took up more drug under alkaline conditions (RPMI 1640 at pH 8.4) than in neutral (pH 7.4) or acidic (pH 6.8) media. Differences were seen in the amount of drug taken up among the filariae studied. B. pahangi and A. viteae took up 7 times more chloroquine per milligram of tissue than did O. volvulus, and 30 times more than D. immitis during a 60-min incubation period at pH 8.4. Sensitivity to the aminoquinolines also increased with increasing media pH, and was measured using parasite motility as an indicator of drug efficacy. Potency of chloroquine against B. pahangi increased 100-fold at pH 8.4 compared to pH 7.4. A. viteae and O. volvulus showed similar sensitivity to chloroquine compared to B. pahangi; D. immitis was less sensitive. While uptake of chloroquine was linear from pH 6.8 to 8.4, B. pahangi was unaffected by 32 microM of the drug below pH 7.6; at any pH above this, motility of this parasite was completely inhibited. Calculations of the internal pH of this parasite indicated that it shifted upwards significantly with changes in media pH. It was concluded that these shifts in internal pH may render parasites more sensitive to the effects of chloroquine.
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PMID:pH-dependent uptake and macrofilaricidal effects of chloroquine on adult filarial parasites in vitro. 291 28

The survival in culture of adult female Brugia pahangi, Acanthocheilonema viteae, and Onchocerca volvulus and adult male Onchocerca gibsoni was assessed by measuring parasite motility. Survival of all species was maximal in a nutritionally complex medium (RPMI-1640). All species survived for up to 48 hr in a simpler medium in which the only energy source was 10 mM glutamine; motility in this medium was dependent upon pH. For the species of Onchocerca, motility was maintained better in the presence of glutamine as the sole energy source than in glucose-only medium. Motility of B. pahangi incubated in 10 mM succinate was equivalent to that seen with 10 mM glutamine, but no other tricarboxylic acid intermediate supported this parasite in vitro. Antimycin A (1 microM) and potassium cyanide (KCN, 100 microM) paralyzed B. pahangi incubated in 10 mM glutamine, an effect antagonized by glucose. KCN at 10 or 100 microM was effective also against Onchocerca gutturosa in glutamine-only medium. Several glutamine antimetabolites reduced motility of B. pahangi by 72 hr. This inhibition was prevented by 2 mM glutamine. However, the inhibition of motility in the species of Onchocerca caused by these compounds was attenuated only partially by glutamine. These data demonstrate that, under certain conditions, filarial nematodes can utilize non-sugar substrates as energy sources. The differential sensitivity seen among these organisms to mitochondrial toxins and glutamine antimetabolites may be related to the extent to which they can use these alternative substrates to generate energy.
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PMID:Glutamine-supported motility of adult filarial parasites in vitro and the effect of glutamine antimetabolites. 845 26