To date clinical research on the initiation of labor could not clarify what was the factor or factors that put into action the uterine contractile system. Pharmacological means demonstrated participating in a manner similar to the physiology in stimulating uterine contraction, only appeared in the world, oxytocin, neurohormone composed of eight amino acids whose mother substance is produced by the hypothalamus and is stored and secreted by the posterior lobe of the pituitary.

To date clinical research on the initiation of labor could not clarify what was the factor or factors that put into action the uterine contractile system. Pharmacological means demonstrated participating in a manner similar to the physiology in stimulating uterine contraction, only appeared in the world, oxytocin, neurohormone composed of eight amino acids whose mother substance is produced by the hypothalamus and is stored and secreted by the posterior lobe of the pituitary.

As widely known, the neotropical region is represented by Central America, south of Mexico, Baja California Peninsula, northwestern of Mexico, Caribbean Islands, south of Florida and South America. On the basis of the outstanding and peculiar biodiversity of the region, a great number of helminthological studies related to the parasites occurring in animals present in the different environments of the area, has been accounted.

The present findings update of previously published results on the nematodes parasitizing Brazilian mammals, with the inclusion of other genera, species and hosts. Measurements and illustrations are only related to the nematodes representing new taxa, and to those that were either redescribed or reported in Brazil occurring in mammals since 1997: Ancylostoma pluridentatum (Alessandrini, 1905), Angiostrongylus lenzii Souza, Simões, Thiengo, Lima, Mota, Rodrigues-Silva, Lanfredi, Maldonado Jr, 2009, Anisakis physeteris Baylis, 1923, A. simplex (Rudolphi, 1808) Dujardin, 1845, A. typica (Diesing, 1860), Anisakis sp., Ascaris elongata (Rudolphi, 1819), Avellaria intermedia Durette- Desset, Gonçalves & Pinto, 2006, Cheiropteronema globocephala Sandground, 1929, Contracaecum sp., Dentostomella translucida Schulz & Krepkorgorskaya, 1932, Freitastrongylus angelae Gonçalves, Pinto &...

During studies of fish helminths, deposited in the Helminthological Collection of the Oswaldo Cruz Institute (CHIOC), some samples of nematodes were studied and identified as Rhabdochona uruyeni Diaz-Ungria, 1968. The present status of the species occurring in South America is discussed and updated. To facilitate further accesses, a worldwide bibliographical survey related to systematic, taxonomic, morphological, biological, cladistical and ecological approaches to the genus, covering a period of 165 years is presented. To date, Rhabdochona (Rhabdochona) acuminata is referred in Argentina, Brazil, and Ecuador, together with Rhabdochona (Filochona) fabianae in Argentina and Rhabdochona (Rhabdochona) uruyeni in Venezuela and now in Brazil, for the first time and in a new host. Also, Rhabdochona spp. are cited in Argentina, Brazil and Peru. Rhabdochona colossomi Diaz-Ungria, 1968 is conside...

Forty-six samples of nematodes recovered from Brazilian specimens of Crotalus durissus Linnaeus, 1758, commonly named rattlesnake were studied. Snakes either died in captivity, under which they were kept for production of serum, or were found dead in nature. Other samples of nematodes from this host and preserved} in the Helminthological Collection of the Oswaldo Cruz Institute (CHIOC) were also analyzed. The most prevalent species were those of the genus Ophidascaris Baylis, 1920: O. arndti Sprehn, 1929, O. durissus Panizzutti, Santos, Vicente, Muniz-Pereira & Pinto, 2003, O. sicki Freitas, 1951, O. tuberculatum Siqueira, Panizzutti, Muniz-Pereira & Pinto, 2005 and Ophidascaris sp., followed by specimens allocated in Hexametra Travassos, 1920: H. boddaertii (Baird, 1860) Kreis, 1944, and Kalicephalus Molin, 1861: K. inermis macrovulvus Caballero, 1954, Kalicephalus sp. Also, spe...

The first case of a natural helminth infection with the cestode Taenia mustelae in a specimen of the procyonid Bassarycion gabbii, the bushy-tailed olingo, from the municipality of Barcelos, State of Amazonas, Brazil is reported here. Achecklist of 15 cestode species parasitizing other procyonid hosts in the Americas, between 1958 and 2009 is included in order to update previous data. In the considered period there are no records in Mexico and Central America countries. This is the first report of T. mustelae in South America and B. gabbii is a new host record for this cestode species.

To date there were no reports of the history of Ancylostoma pluridentatum that was described in Italy, on the basis of Brazilian specimens in 1905. The only two further autochthonous references of the species occurred in 1910 and 2008, respectively, with no previous historical data during those 98 years in which the species was ignored in Brazil; in the present note, the occurrence of A. pluridentatum in the Americas is briefly accounted, on what concerns geographical distribution and hosts. In South America, A. pluridentatum is referred in the southeast (Atlantic Forest) and north (Amazon rain forest) regions of Brazil, in Argentina (Formosa Province) and in Colombia (Choco, Nariño); in Central America is cited in Panama (Achiote, Colon) and in North America in north, southern and south regions of Florida.

Between October 2006 and March 2008, 60 specimens of Paralichthys isosceles were captured in the littoral of the State of Rio de Janeiro, Brazil, to be investigated for anisakid nematodes, due to their zoonotic relevance. Five species of larval anisakid were present, in a total amount of 1,900 worms. One thousand eighty hundred and twenty larvae of Hysterothylacium sp., 71 of Raphidascaris sp., four of Terranova sp., three of Anisakis simplex and two of Contracaecum sp. were recovered. Parasites were found infecting the abdominal cavity, mesentery, intestine, liver, stomach mucosa, stomach, ovaries, abdominal musculature, and serosas of the heart, spleen, stomach, kidneys and ovaries. Hysterothylacium sp. appeared with a prevalence (P) of 100%, mean intensity (MI) of 30.3, range of infection (RI) of 1 to 596 and mean abundance (MA) of 30.3; Raphidascaris sp. with P = 36.7%, MI = 3.2, RI ...

Results of fecal examinations have been compared with those obtained during necropsies of snakes infected with helminths. Stool samples from specimens of Bothrops jararaca and B. alternatus were investigated and three animals were positive for eggs during coprological screenings: one case representing authochtonous snake parasites, other related to species accidentally introduced together with naturally infected mice snakes fed on, and another with the association of both. Necropsies of those same specimens, showed the presence of the nematodes Ophidascaris travassosi Vaz, 1938, Kalicephalus costatus (Rudolphi, 1819), K. inermis Molin, 1861, Kalicephalus sp. and Acanthorhabdias acanthorhabdias Pereira, 1927. Bothrops jararaca is a new host record for O. travassosi and Bothrops alternatus for A. acanthorhabdias; the gross pathological lesions induced by the nematodes are reported.

From October 2006 to March 2008, sixty specimens of Paralichthys isosceles, were captured in the littoral of the State of Rio de Janeiro Brazil. The present study deals with the taxonomic identification of the cestodes parasitizing this fish species, as well with the analysis of parasitological indexes, sites of infection, taking into account the hygienic-sanitary importance of the host in Brazilian and foreign markets. Fifty-six (93.3%) out of the collected fishes were infected with at least one specimen of metacestodes. Diphyllobothriidea were represented by plerocercoids of two species: Diphyllobothrium sp. 1 (similar to D. latum) in stomach, stomach mucosa and mesentery and Diphyllobothrium sp. 2 (similar to D. dendriticum) in intestine, liver, ovary and abdominal cavity. Trypanorhyncha, were represented by Grillotia carvajalregorum, in stomach, intestine, liver, mesentery, abdominal...