Schistosome adult

Irie, Y. and Iwamura, Y. (1 993) Host-related DNA sequences are localized in the body of schistosome adults. Parasitology 107, 51 9-528. 

Fig. 7.6. A and B. Confocal laser scanning microscographs of schistosome adults showing auto-fluorescence 488 nm was used for excitation and 520 nm for emission. A. Mid-body of a male schistosome with the focus on the lumen of the bipartite gut (g). In bombarded worms, a pale auto-fluorescence sometimes occurs under in vitro culture conditions. This auto-fluorescence occurs over a wide spectrum of wavelengths.

The structure and function of schistosome Ca2+ channel subunits have recently begun to be elucidated (Kohn et at., 2001 a,b). Schistosome adults express at least three subtypes of HVA Ca2+ channel a1 subunits. Two of these sub-types are most similar to a1 subunits from the non-L-type class, while one is most closely related to the L-type class of a1 subunits. Schistosomes (and presumably other platy-helminths) may be unique among the invertebrates in that they have genes encoding two subtypes of non-L-type a1 subunits, while other invertebrates that have been examined contain only a single representative for each of these two classes (Jeziorski et ah, 2000a Littleton and Ganetzky, 2000). 

Wippersteg V, Ribeiro F, Liedtke S et al (2003) The uptake of Texas Red-BSA in the excretory system of schistosomes and its colocalisation with ER60 promoter-induced GFP in transiently transformed adult males. Int J Parasitol 33 1139-1143... 

The answer is a. (Hardman, pp 1020-1022.) Praziquantel is a broad-spectrum antihelminthic agent. It appears to kill the adult schistosome by... 

In schistosome infections of experimental animals, praziquantel is effective against adult worms and immature stages, and it has a prophylactic effect against cercarial infection. 

Agnew, A.M Murare, H.M. and Doenhoff, M.J. (1993) Immune attrition of adult schistosomes. Parasite Immunology 15, 261-271. 

Though elucidating the mode of action of praziquantel has proved a daunting task, the effects of the drug on adult schistosomes do provide clues to potential targets for the drug. Application of praziquantel results in a... 

Application of praziquantel results in a rapid uptake of 45Ca2+ in adult male schistosomes (and a much slower influx of Na+ Pax et al., 1978). The effects of praziquantel on both contraction of the worm s musculature and disruption of the parasite tegument are... 

To date, no native Ca2+ currents from schistosome cells have been published. In fact, voltage-clamp analyses of muscle cells isolated from adult Schistosoma mansoni have revealed no inward currents at all, apparently due to technical limitations (Day et ah, 1 993). However, isolated muscle cells from S. mansoni do show Ca2+-dependent contractility (Day et ah, 1 994). 

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