Nematode infections treatment

A cardinal role for IL-4 in host protection against intestinal nematode infection was first shown in the H. polygyrus challenge model. Worm expulsion was delayed following treatment with anti-IL-4 or anti-IL-4 receptor monoclonal antibodies, while control treated animals successfully cleared infection (Urban et al., 1991b). Blockade of the IL-4 receptor effectively prevents the in vivo function of IL-4 and IL-13, as these two cytokines share the IL-4 receptor a-chain for signalling functions (Lin et al, 1995). In... 

The involvement of mast cells in host protection against nematode infection is well characterized in T. spiralis infection. W/Wv mice exhibited a significant delay in worm expulsion, and treatment with either anti-SCF or anti-SCF receptor monoclonal antibody dramatically inhibited mast cell responses and expulsion of T. spiralis for the duration of treatment (Donaldson et al., 1996). W/Wv mice also lack interstitial cells of cajal and intraepithelial y T cells (Maeda et al., 1992 Puddington et al., 1994), which may contribute to the impaired response in these animals (see below). However, supporting evidence of a role for mast cells in protection against T. spiralis comes from studies in which overexpression of IL-9 in mice (which is known to influence the mast cell responses see above) resulted in an extremely rapid mast cell-dependent expulsion of T. spiralis (Faulkner et al., 1997). 

Eosinophilia is a hallmark of intestinal nematode infection and is known to be under the control of IL-5 (Finkelman et al., 1992). As discussed above, treatment with anti-IL-5 monoclonal antibody (and so ablation of eosinophilia) had no effect on expulsion of T. muris, 77. polygyms, N. brasiliensis or T. spiralis infections, suggesting that either redundant mechanisms operate under these circumstances or that eosinophils are not a critical component of effector responses operating against most murine... 

Urban, J.F., Maliszewski, C.R., Madden, K.B., Katona, I.M. and Finkelman, F.D. (1995) IL-4 treatment can cure established gastrointestinal nematode infections in immunocompetent and immunodeficient mice. Journal of Immunology 154, 4675-4684. 

Ketzis, J. K., Taylor, A., Bowman, D. D., Brown, D. L., Wamick, L. D. and Erb, H. N. (2002). Chenopodium ambrosioides and its essential oil as treatments for Haemonchus contortus and mixed adult-nematode infections in goats . Small Ruminant Research, 44, 193-200. 

Ivermectin (Mectizan, Stromectol) is the primary treatment for filarial nematode infections (onchocerciasis) that invade ocular tissues and cause loss of vision (river blindness). Ivermectin may also be used in filarial infections in other tissues (lymphatics, skin). This drug is a secondary agent for treating intestinal nematodes such as strongyloidosis. 

The salicylanilide drugs have been widely used to treat intestinal tapeworm and liver fluke infections in humans and animals. Their use in the treatment of hydatid diseases, schistosomiasis and nematode infections is limited [11]. 

Mebendazole is widely used for the treatment of nematode infections but is contraindicated in the pregnant patient because of possible embryotoxicity. Think back over the dmgs used for the treatment of bacterial, fungal, protozotd, and viral infections. 

It is widely used across the globe for the management and treatment of intestinal nematode infection. It is also quite effective as a single-dose-treatment for ascariasis, New and Old World hookworm infections, and trichuriasis. It has been observed that a recommended multi-dose therapy with albendazol may help in the complete eradication of pinworm, threadworm, capillariasis, chlonorchiasis, and hydated disease as well. However, the overall observed effectiveness of albendazole against tapeworms (cestodes) is obviously more variable and less impressive apparently. 

It has been amply demonstrated that the natural avermectins invariably exhibit minimal biologic profile of activity, whereas invermectin has proven to be extermely useful and hence recognized for the management and treatment of good number of nematode infections. Besides, it is found to be active against arthropods that usually parasitize the animal folks. ... 

Morantel The conventional use of veterinary anthelmintics is for the therapy of existing Infections and does not prevent rapid reinfection in circumstances of continuous environmental challenge such as pasture grazing. A new sustained release morantel tartrate delivery system for cattle has been described.42 a single oral treatment administered at turnout provides protection against gastrointestinal nematode infection for the entire grazing season. Improved performance compared with untreated or conventionally medicated cattle was also observed. 

Extracted from the soil actinomycete Streptomyces avermitilis, the natural avermectins are 16-membered macrocyclic lactones that, on reduction of the C22-23 double bond, give rise to ivermectin (IVM), which is an 80 20 mixture of dihydroavermectin Bia and Bip, respectively. The natural avermectins have minimal biological activity, but IVM has proven to be quite beneficial in the treatment of various nematode infections. 

Nematode Infections - There have been several review articles dealing with chemotherapy of nematode Infections.5.7> 9 Reports on tetramisole (XVIII) have appeared confirming its activity against ascarid infections in man.l " As indicated earlier, treatment of other helminth infections was not as satisfactory. 50-152 ew synthesis of tetramisole starting with the condensation of styrene oxide emd ethylenimine has been reported. 

Mepacrine (Fig. 25.14) can be used in resistant giardiasis. This drug was developed during the Second World War to treat malaria but has been re-introduced to treat giardiasis and is also the subject of research into the treatment of Alzheimer s disease. Albendazole may also be used as an alternative and is described below under the treatment of nematode infections. 

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