Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Parasite Control”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 361 records · Page 20Linked to original sources
PubMed1981

Control of parasitic infestations in killifish (Fundulus parvipinnis).

California killifish (Fundulus parvipinnis) trapped in a Southern California estuary were infested with Gyrodactylus sp, Argulus sp, or Ergasilus sieboldii. They were treated with 0,0-dimethyl 2,2,2-trichloro-1-hydroxyethylphosphonate (DTHP). The effective dosage regimen for Gyrodactylus was 7.50 mg/l for 1 hour on day 1, 3.25 mg/l for 1 hour on day 5, and 0.75 mg/l for 1 hour on day 9; for Argulus, 2.50 mg/l for 1 hour once only; for Ergasilus, 2.50 mg/l for 1 hour once every third day for three treatments. Toxicity testing indicated that repetitive doses of 4.20 mg/l were toxic and that static exposures of more than 1 hour to doses of 7.50 mg/l were lethal to Fundulus.

Animals↗
PubMed2002

Metabolic and symbiotic interactions in amino acid pools of the pea aphid, Acyrthosiphon pisum, parasitized by the braconid Aphidius ervi.

Aphidius ervi Haliday (Hymenoptera, Braconidae) is an endophagous parasitoid of the pea aphid, Acyrthosiphon pisum (Harris) (Homoptera, Aphididae). This parasitoid strongly redirects host reproduction and metabolism to favour nutrition and development of its juvenile stages. Parasite-regulated biosynthesis and mobilization of nitrogen metabolites determine a significant increase of host nutritional suitability. The aim of the present study was mainly to investigate the temporal changes of A. pisum amino acid pools, as affected by A. ervi parasitism, and to assess the role of the aphid bacterial endosymbiont Buchnera in determining the observed changes. In parasitized aphids, we observed a very significant increase in total free amino acids, compared with synchronous non-parasitized controls, starting from day 4 after parasitization (+51%). This trend culminated with more than doubling the control value (+152%) on day 6 after parasitization. However, a significant "parasitism" effect was observed only for 10 of the 28 amino acids detected. Tyrosine accumulation was the most prominent parasitoid-induced alteration, with a fourfold increase over control levels registered on day 6. In parasitized hosts, the amino acid biosynthetic capacity of Buchnera was unaltered, or even enhanced for the phenolic pool, and contributed greatly to the definition and maintainance of host free amino acid pools. The hypertyrosinemic syndrome was not dependent on food supply of the aromatic nucleus but was induced by parasitism, which likely enhanced the aromatic shuttle mediating phenylalanine transfer from bacteria to the host tissues, where tyrosine conversion occurs. This process is likely associated with a selective disruption of the host's functions requiring tyrosine, leading to the remarkable accumulation of this amino acid. The possible mechanisms determining these parasitism-induced host alterations, and their nutritional significance for the developing parasitoid larva, are discussed.

Journal Article↗
PubMed2002

Influence of parasite load on the ability of type 1 T cells to control Leishmania major infection.

BALB/c mice infected with Leishmania major developed a type 2 immune response which failed to control parasite replication. We found that scid mice that received splenocytes from BALB/c mice that had been infected for 3 weeks with L. major (a type 2 cell population) and that were subsequently infected with L. major were protected when they were treated with interleukin 12 (IL-12). In contrast, IL-12 was ineffective at protecting BALB/c mice infected for 3 weeks, suggesting that a high parasite load regulates the development of protective immunity. To determine how this regulation operates, we performed a series of adoptive transfers of naïve, type 1 or type 2 splenocytes into scid mice. The recipient scid mice were infected either for 5 weeks prior to cell transfer (and thus had a high parasite load) or at the time of cell transfer. scid mice that were infected for 5 weeks and received a type 1 cell population were able to cure their lesions. However, when 5-week-infected scid mice received both type 1 and 2 cell populations, they were unable to control their infections. In contrast, the same type 1 and 2 cells transferred to naïve scid mice, which were subsequently infected, provided protection. In addition, we found that naïve cells mediated protection in scid mice with established lesions. These results show that high parasite numbers do not block type 1 protective responses or the development of type 1 responses. Instead, the influence of a high parasite load is dependent on the presence of a type 2 cell population.

Animals↗
PubMed1991

Epizootiology of helminth parasitism in a beef cow/calf herd in Minnesota.

To test the effect of a parasite control program for cattle, 2 groups of similar composition were grazed on separate, but equivalent, improved pastures. Cattle in 1 group were treated with fenbendazole at 5.0 mg/kg of body weight at the time they were turned out on pasture in the spring and again at midsummer, when the cattle were moved to a new pasture. The control group was not treated. Parasite egg counts were significantly (P less than 0.04) lower in the treated group. Trichostrongyle-type eggs were the most prevalent throughout the year, except in the month of May, when Strongyloides papillosus eggs were predominant. The number of worms recovered from tracer calves was lower for those on pastures where the treated group grazed than for those on the control group's pasture. The most consistently recovered parasite was Ostertagia ostertagi, and hypobiosis was observed.

Animals↗
PubMedDate not supplied

[Intervention for improving the coproparasitological diagnosis in the Province of Las Tunas, Cuba, 1993-1994].

Control of quality of coproparasitological diagnosis was carried out in the Province "Las Tunas", between January and March 1993, It was found that 72% of coproparasitological microscopists had deficiencies related to the diagnosis, due to several causes: The microscopists did not receive any periodical training, as they did not participate at the parasitological section; the microscopists had no manual of reference; they had less than ten years of experience; they did not know the concentration technics that were established in the country. Between July 1993 and January 1994 two Medical Parasitology Courses were imparted. In July 1994 another quality control was performed. 80% of evaluated microscopists obtained good results. Through this study was established the National Parasitology Quality System Control that supports the National Intestinal Parasites Control Program.

Cuba↗