8 research outputs found

    Bacillus thuringiensis Cry5B Protein Is Highly Efficacious as a Single-Dose Therapy against an Intestinal Roundworm Infection in Mice

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    Intestinal parasitic nematode diseases infect over one billion people and cause significant disease burden in children (growth and cognitive stunting, malnutrition), in pregnant women, and via their dampening of the immune system in infected individuals. In over thirty years, no new classes of anti-roundworm drugs (anthelmintics) for treating humans have been developed. Because of limitations of the current drugs and the threat of parasite resistance, new anthelmintics are needed. The soil bacterium Bacillus thuringiensis (Bt) produces crystal (Cry) proteins that specifically target and kill insects and nematodes and is used around the world as a safe insecticide. Here we test the effects of the Bt Cry protein Cry5B on a chronic, natural intestinal roundworm infection in mice, namely the helminth parasite Heligmosomoides bakeri. We find that a single dose of Cry5B can eliminate 70% of the parasites and can almost completely block the ability of the parasites to produce progeny. Comparisons of Cry5B's efficacy with known anthelmintics suggest its activity is as good as or perhaps even better than those currently used. Furthermore, this protein is rapidly digested by simulated stomach juices, suggesting that protecting it from these juices would reveal a superior anthelmintic

    Dysphania ambrosioides (L.) Mosyakin & Clemants

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    Dysphania ambrosioides (L.) Mosyakin & Clemants (= Chenopodium ambrosioides L.) is an American aromatic species used as medicinal and culinary purposes since pre-Columbian times by Aztecs and Mayans in Mesoamerica (where is called epazote) and Andean communities and many others in South America (where is better known as paico). Currently, it is globally known by a wide diversity of cultures around the world, due to its cultivation and naturalization. Its uses are currently widespread in pluricultural contexts, by means the commercial circuits and mass media, especially the Internet. The main active constituents are essential oils, to which owes its aroma and flavor. It is toxic in high doses, but safe if is consumed in appropriated concentrations. The most widespread folk therapeutic use is as antiparasitic (anthelmintic, antimicrobial), and it is also employed against gastrointestinal disorders, as hypotensive, antipyretic, vulnerary, analgesic, anti-inflammatory, antitumor, sedative and anxiolytic, among others, many of which have been evaluated scientifically. The researches on its anticancer activity are very promising.Fil: Hurrell, Julio Alberto. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de EtnobotĂĄnica y BotĂĄnica Aplicada; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - La Plata; Argentin

    The precambrian mafic magmatic record, including large igneous provinces of the kalahari craton and its constituents : A paleogeographic review

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    The study of Precambrian dyke swarms, sill provinces and large igneous provinces on the Kalahari craton in southern Africa has expanded greatly since the pioneering work initiated almost four decades ago. The main contributors to this progress have been a large number of precise U–Pb crystallization ages of mafic rocks, published in a number of recent papers. This information is compiled here into a series of maps that provide a nearly 3 billion year intraplate magmatic record of the Kalahari craton and its earlier constituents, the proto-Kalahari, Kaapvaal and Zimbabwe cratons. We also review their possible paleogeographic relations to other cratons or supercontinents. This review provides a more accessible overview of individual magmatic events, and mostly includes precise U–Pb ages of mafic dykes and sills, some of which can be linked to stratigraphically well-constrained volcanic rocks. The extrusion ages of these volcanic units are also starting to be refined by, among others, in situ dating of baddeleyite. Some mafic dyke swarms, previously characterized entirely on similarity in dyke trends within a swarm, are found to be temporally composite and sometimes consist of up to three different generations. Other mafic dyke swarms, with different trends, can now be linked to protracted volcanic events like the stratigraphically well preserved Mesoarchean Nsuze Group (Pongola Supergroup) and Neoarchean Ventersdorp Supergroup. Following upon these Archean events, shorter-lived Proterozoic large igneous provinces also intrude the Transvaal Supergroup, Olifantshoek Supergroup and Umkondo Group, and include the world’s largest layered intrusion, the Bushveld Complex. Longer-lived late Paleoproterozoic magmatic events are also preserved as mafic intrusions and lava units within the Waterberg and Soutpansberg groups as well as the granitic basement. Many gaps in our knowledge of the Precambrian mafic record of the Kalahari craton remain, but further multi-disciplinary studies combining the latest advances in U–Pb geochronology and both paleomagnetism and geochemistry will help solve the Precambrian paleogeographic puzzle
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