Friday, August 14, 2009

What's new for 'Trypanosomatids' in PubMed

This message contains My NCBI what's new results from the National Center for Biotechnology Information (NCBI) at the U.S. National Library of Medicine (NLM).
Do not reply directly to this message.

Sender's message:

Sent on Friday, 2009 Aug 14
Search kinetoplastids OR kinetoplastid OR Kinetoplastida OR "trypanosoma brucei" OR leishmania OR brucei OR leishmaniasis OR "African trypanosomiasis"
Click here to view complete results in PubMed. (Results may change over time.)
To unsubscribe from these e-mail updates click here.



PubMed Results
Items 1 -4 of 4

1: J Immunol. 2009 Aug 12. [Epub ahead of print]Click here to read

Processing and Presentation of Variant Surface Glycoprotein Molecules to T Cells in African Trypanosomiasis.

Dagenais TR, Freeman BE, Demick KP, Paulnock DM, Mansfield JM.

*Department of Bacteriology and.

Th1 cell responses to the variant surface glycoprotein (VSG) of African trypanosomes play a critical role in controlling infection through the production of IFN-gamma, but the role of APCs in the induction and regulation of T cell-mediated protection is poorly understood. In this study, we have investigated the Ag presentation capabilities of dendritic cells (DCs) and macrophages during early trypanosome infection in relatively resistant responder and susceptible nonresponder mouse strains. Splenic DCs appeared to be the primary cell responsible for activating naive VSG-specific Th cell responses in resistant responder animals through the coordinated up-regulation of costimulatory molecules, secretion of IL-12, and presentation of VSG peptides to T cells in vivo. Splenic DC depletion and the down-regulation of costimulatory markers on splenic macrophages were observed in susceptible animals and may be associated with the inability of these animals to elicit a significant VSG-specific T cell response. In contrast to splenic APCs, peritoneal macrophages secreted NO, failed to activate naive Th cells in vitro, and presented relatively low levels of VSG peptides to T cells in vivo. Thus, VSG-specific Th1 cell responses may be determined by tissue- and cell-specific differences in Ag presentation. Additionally, all APCs from resistant and susceptible strains displayed a reduced ability to process and present newly encountered exogenous Ag, including new VSG molecules, during high parasitemia. Thus, initial uptake of VSG (or other trypanosome factors) may interfere with Ag presentation and have dramatic consequences for subsequent T cell responses to other proteins.

PMID: 19675169 [PubMed - as supplied by publisher]

2: J Hand Surg Eur Vol. 2009 Aug;34(4):555-6.Click here to read

Cutaneous leishmaniasis: a diagnosis of suspicion.

Holmes WJ, Tehrani H, Liew S.

PMID: 19675049 [PubMed - in process]

3: Exp Parasitol. 2009 Sep;123(1):73-80. Epub 2009 Jun 9.Click here to read LinkOut

Trypanosoma cruzi: activity of heterocyclic cationic molecules in vitro.

Pacheco MG, da Silva CF, de Souza EM, Batista MM, da Silva PB, Kumar A, Stephens CE, Boykin DW, Soeiro Mde N.

Lab. Biologia Celular, Instituto Oswaldo Cruz, FIOCRUZ, M.N.C. Soeiro, Rio de Janeiro, Brazil.

Chagas disease remains a serious public health problem in several Latin American countries. New chemotherapy is urgently needed since current drugs are limited in efficacy and exhibit undesirable side effects. Aromatic diamidines and analogs are well known anti-parasitic agents and in this study, we have evaluated the in vitro trypanocidal effect of several different heterocyclic cationic compounds, including diamidines (DB1195, DB1196 and DB1345), a monoamidine (DB824), an arylimidamide (DB613A) and a guanylhydrazone (DB1080) against amastigotes and bloodstream trypomastigotes of Trypanosoma cruzi, the etiological agent of Chagas disease. Our present findings showed that all compounds exerted, at low-micromolar doses, a trypanocidal effect upon both intracellular parasites and bloodstream trypomastigotes of T. cruzi. The activity of DB1195, DB1345, DB824 and DB1080 against bloodstream forms was reduced when these compounds were assayed in the presence of mouse blood possibly due to their association with plasma constituents and/or due to metabolic instability of the compounds. However, trypanocidal effects of DB613A and DB1196 were not affected by plasma constituents, suggesting their potential application in the prophylaxis of banked blood. In addition, potency and selectivity of DB613A, towards intracellular parasites, corroborate previous results that demonstrated the highly promising activity of arylimidamides against this parasite, which justify further studies in experimental models of T. cruzi infection.

PMID: 19520077 [PubMed - indexed for MEDLINE]

4: J Org Chem. 2009 Jun 5;74(11):4203-7.Click here to read LinkOut

Gracilioethers A-C, antimalarial metabolites from the marine sponge Agelas gracilis.

Ueoka R, Nakao Y, Kawatsu S, Yaegashi J, Matsumoto Y, Matsunaga S, Furihata K, van Soest RW, Fusetani N.

Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan.

Three new antiprotozoan compounds, gracilioethers A-C (1-3), have been isolated from the marine sponge Agelas gracilis. Their structures were elucidated on the basis of spectroscopic and chemical methods. Gracilioethers A-C showed antimalarial activity against Plasmodium falciparum with IC(50) values of 0.5-10 microg/mL, whereas gracilioether B (2) also showed antileishmanial activity.

PMID: 19402618 [PubMed - indexed for MEDLINE]

Posted by at

No comments:

Post a Comment

Subscribe to: Post Comments (Atom)