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The physiological interactions during the course of the immune response to helminthes are complex. As our understanding of the neuroendocrine system grows, it has become increasingly clear that this complex network of neurotransmitters, hormones, and cytokines plays an important role in mediating immunity, in general, but in the case of helminthes this interaction among different systems is crucial. Helminthes present a complex relationship in the host's physiological systems, with neuro and hormonally dependent host factors such as sex, age, and the host physiological status correlated with parasite success. On top of the effect that this particular type of parasites may have on the invaded host, recent experimental evidence suggest that helminth parasites not only actively evade immune response, but are also able to exploit the hormonal microenvironment within their host to favor their establishment, growth and reproduction. The close interaction of the worm with the host's homeostatic systems, the molecules produced by them, and the activation of immune mediated mechanisms to eliminate it, activate a complex neuroendocrine network, that produces strong behavioral changes in the infected host. Understanding how the host's neuroendocrine system can under certain circumstances favor the establishment of a parasitic infection opens interesting perspectives into the host parasite relationship field. This review focuses on the host-parasite neuroendocrine network activated by parasite worm infections. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii proliferates and organizes within a parasitophorous vacuole in rosettes around a residual body and is surrounded by a membranous nanotubular network whose function remains unclear. Here, we characterized structure and function of the residual body in intracellular tachyzoites of the RH strain. Our data showed the residual body as a body limited by a membrane formed during proliferation of tachyzoites probably through the secretion of components and a pinching event of the membrane at the posterior end. It contributes in the intravacuolar parasite organization by the membrane connection between the tachyzoites posterior end and the residual body membrane to give place to the rosette conformation. Radial distribution of parasites in rosettes favors an efficient exteriorization. Absence of the network and presence of atypical residual bodies in a ΔGRA2-HXGPRT knock-out mutant affected the intravacuolar organization of tachyzoites and their exteriorization. [ABSTRACT FROM AUTHOR]

Abstract: Endosulfan is a hazardous organochlorine pesticide banned or restricted in several countries. However, it has been found in the environment and in animal samples. To study a potential way to bioremediate soils contaminated with this pesticide, two plant species of the genus Ocimum were studied: Ocimum basilicum L. and Ocimum minimum L., since they are economically feasible and well adapted to the climatic conditions of the Nayarit zone (Mexican pacific coast). Young plants were transplanted into soil experimentally polluted with endosulfan. Growth of both species was not affected by endosulfan, the plants grew, flourished, and produced seeds; 30 days later, endosulfan concentration was lower in the soil with O. basilicum than in the soil without plants. On day 90, no differences in endosulfan concentrations were found between soil with or without O. minimum. At day 1, plants in the polluted soil showed lipoperoxidation, as measured by thiobarbituric acid-reactive species (TBARS). Interestingly, a higher TBARS value was observed at day 3 in transplanted plants as compared to non-transplanted plants. In conclusion, both species can endure endosulfan pollution (as high as 1gkg−1) in soils. O. basilicum seems to be an adequate candidate for bioremediation of soils polluted with endosulfan. [Copyright &y& Elsevier]