Saturday, May 2, 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 Saturday, 2009 May 02
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 -7 of 7

1: Acta Crystallogr Sect F Struct Biol Cryst Commun. 2009 May 1;65(Pt 5):450-4. Epub 2009 Apr 24.

Geobacillus stearothermophilus 6-phosphogluconate dehydrogenase complexed with 6-phosphogluconate.

Cameron S, Martini VP, Iulek J, Hunter WN.

University of Dundee, Scotland, UK.

Two crystal structures of recombinant Geobacillus stearothermophilus 6-phosphogluconate dehydrogenase (Gs6PDH) in complex with the substrate 6-phosphogluconate have been determined at medium resolution. Gs6PDH shares significant sequence identity and structural similarity with the enzymes from Lactococcus lactis, sheep liver and the protozoan parasite Trypanosoma brucei, for which a range of structures have previously been reported. Comparisons indicate that amino-acid sequence conservation is more pronounced in the two domains that contribute to the architecture of the active site, namely the N-terminal and C-terminal domains, compared with the central domain, which is primarily involved in the subunit-subunit associations required to form a stable dimer. The active-site residues are highly conserved, as are the interactions with the 6-phosphogluconate. There is interest in 6PDH as a potential drug target for the protozoan parasite T. brucei, the pathogen responsible for African sleeping sickness. The recombinant T. brucei enzyme has proven to be recalcitrant to enzyme-ligand studies and a surrogate protein might offer new opportunities to investigate and characterize 6PDH inhibitors. The high degree of structural similarity, efficient level of expression and straightforward crystallization conditions mean that Gs6PDH may prove to be an appropriate model system for structure-based inhibitor design targeting the enzyme from Trypanosoma species.

PMID: 19407374 [PubMed - in process]

2: Am J Trop Med Hyg. 2009 May;80(5):704-11.

Leishmaniases in Bolivia: comprehensive review and current status.

García AL, Parrado R, Rojas E, Delgado R, Dujardin JC, Reithinger R.

CUMETROP, Universidad Mayor de San Simón, Cochabamba, Bolivia.

The leishmaniases are protozoan, zoonotic diseases transmitted to human and other mammal hosts by the bite of phlebotomine sandflies. Bolivia has the highest incidence of cutaneous leishmaniasis (CL) in Latin America (LA), with 33 cases per 100,000 population reported in 2006. CL is endemic in seven of the country's nine administrative departments. Visceral leishmaniasis (VL) is comparatively rare and is restricted to one single focus. Most CL cases are caused by Leishmania (Viannia) braziliensis (85% cases); VL is caused by L. (L.) infantum. Seven sandfly species are incriminated as vectors and Leishmania infections have been detected in several non-human mammal hosts. Transmission is associated with forest-related activities, but recently, cases of autochthonous, urban transmission were reported. Because most cases are caused by L. (V.) braziliensis, Bolivia reports the greatest ratio (i.e., up to 20% of all cases) of mucosal leishmaniasis to localized CL cases in LA. Per national guidelines, both CL and VL cases are microscopically diagnosed and treated with pentavalent antimony.

PMID: 19407110 [PubMed - in process]

3: Am J Trop Med Hyg. 2009 May;80(5):700-3.
Comment in:
Am J Trop Med Hyg. 2009 May;80(5):689-90.

Safety and efficacy of high-dose infusions of a preformed amphotericin B fat emulsion for treatment of Indian visceral leishmaniasis.

Sundar S, Singh A, Agarwal D, Rai M, Agrawal N, Chakravarty J.

Kala-Azar Medical Research Center, Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India. drshyamsundar@hotmail.com

Amphotericin B deoxycholate is used as a first-line drug for visceral leishmaniasis (VL) in India. Its major drawbacks are prolonged hospitalization of treated patients and toxicity. An open label phase II study with pre-formed amphotericin B lipid emulsion (ABLE) was conducted to evaluate safety and efficacy of four regimens of 15 mg/kg each administered in 1-2 doses. Regimen 1 was 7.5 mg/kg/day on day 1 and day 3, and regimen 4 was a single bolus infusion of 15 mg/kg. The safety profile was excellent with mild infusion reactions seen in 38% of the patients. Definitive cure was achieved in 100% of the patients treated with regimen 4. The overall cure rate was 87% (95% confidence interval = 75-94%). In this study, ABLE was safe and had excellent efficacy when given as a bolus of 15 mg/kg. More studies with larger number of patients and higher doses are needed to establish acceptable, safe and efficacious regimen.

PMID: 19407109 [PubMed - in process]

4: Am J Trop Med Hyg. 2009 May;80(5):689-90.
Comment on:
Am J Trop Med Hyg. 2009 May;80(5):700-3.

ABLE: a new and improved amphotericin B for visceral leishmaniasis?

Berman J.

PMID: 19407106 [PubMed - in process]

5: Eur Respir J. 2009 May;33(5):1216-9.

Unusual microbes in asthma exacerbation: Alcaligenes xylosoxidans and Leishmania.

Robibaro B, Funk GC, Dekan G, Demetriou D, Ziesche R, Winkler S, Block LH.

Medical University Vienna, Department of Internal Medicine II, Division of Nephrology, General Hospital Vienna, Vienna, Austria. bruno.robibaro@meduniwien.ac.at

Asthma is a chronic inflammatory condition characterised by a variable degree of airflow limitation. Exacerbations during the course of asthma often occur due to environmental factors or infectious, mostly viral, aetiology. The present study reports the case of a 61-yr-old male with severe asthma hospitalised due to increasing respiratory distress. Since recovery was delayed despite anti-obstructive/anti-inflammatory and antibiotic therapy, further diagnostic procedures, including bronchoscopy, were performed in order to attempt to identify the cause of the worsening respiratory condition. The surprising finding consisted of a rare coincidence of concomitant infection with the bacterial pathogen Alcaligenes xylosoxidans, grown from bronchoalveolar lavage fluid, and the protozoan parasite Leishmania spp., revealed by histopathological examination of bronchial mucosal biopsy specimens. This is the first report of an isolated bronchial mucosal involvement of Leishmania in an HIV-negative asthma patient following brief exposure in Leishmania-endemic regions. Further, to the best of the present authors' knowledge, this represents the first description of A. xylosoxidans in asthma, although it is questionable whether it was an infection or colonisation. The present observation identifies previously unreported microbial pathogens associated with asthma exacerbation. Further, the report highlights the importance of obtaining a thorough travel history and applying invasive diagnostic procedures in circumstances of treatment failure, even under unfavourable conditions.

PMID: 19407055 [PubMed - in process]

6: Acta Vet Scand. 2009 Apr 30;51(1):20. [Epub ahead of print]

Visceral leishmaniasis with cardiac involvement in a dog: a case report.

Lopez Pena M, Aleman N, Munoz F, Fondevila D, Suarez ML, Goicoa A, Nieto JM.

ABSTRACT: A dog presented with cutaneous nodules, enlarged lymph nodes and oedema in limbs, face and abdomen. The diagnosis of visceral leishmaniasis was established by identification of Leishmania amastigotes within macrophages from skin and popliteal lymph node biopsies. At necropsy, lesions were found in different organs, but it was particularly striking to observe large areas of pallor in the myocardium. Histological examination revealed an intense chronic inflammatory reaction in many organs, and numerous macrophages were found to contain amastigote forms of Leishmania. The inflammatory reaction was especially severe in the heart, where large areas of the myocardium appeared infiltrated with huge numbers of mononuclear immune cells, causing cardiac muscle atrophy and degeneration. Despite the severe inflammation, the number of parasitized macrophages was low in the myocardium, as revealed by immunohistochemical staining of Leishmania amastigotes. Because cardiac involvement is not usually described in this condition, this dog represents a very rare case of canine visceral leishmaniasis with affection of the myocardium.

PMID: 19405946 [PubMed - as supplied by publisher]

7: Mem Inst Oswaldo Cruz. 2008 Dec;103(8):824-30.Click here to read LinkOut

Ecological aspects of Rhodnius nasutus Stål, 1859 (Hemiptera: Reduviidae: Triatominae) in palms of the Chapada do Araripe in Ceará, Brazil.

Dias FB, Bezerra CM, Machado EM, Casanova C, Diotaiuti L.

Laboratório de Triatomíneos e Epidemiologia da Doença de Chagas, Centro de Pesquisas René Rachou-Fiocruz, Belo Horizonte, MG, Brasil.

The aim of this work is to present aspects related to the ecology of Rhodnius nasutus Stål, 1859 in palms from Chapada do Araripe in Ceará, Brazil. The following five species of palms were investigated: babaçu (Attalea speciosa), buriti (Mauritia flexuosa), carnaúba (Copernicia prunifera), catolé (Syagrus oleracea) and macaúba-barriguda (Acrocomia intumescens). Fifth palms were dissected (10 specimens for each species). The overall infestation index was 86%, with a total of 521 triatomines collected. The Trypanosoma cruzi Chagas, 1909 Index was 16.8% and two insects presented mixed infection with Trypanosoma rangeli Tejera, 1920. A precipitin test showed that R. nasutus from palms of Chapada do Araripe are associated with opossum and bird although other possible bloodmeals were observed. Our results showing a high index of infestation of the palms as well as T. cruzi infection, the association of R. nasutus with the most diverse species of palms and proximity of these palms to houses demonstrate the importance of this area for sylvatic T. cruzi transmission and suggest the need for epidemiological surveillance in the region of the Chapada do Araripe.

PMID: 19148424 [PubMed - indexed for MEDLINE]

Posted by at

No comments:

Post a Comment

Subscribe to: Post Comments (Atom)