[leish-l] Fwd: Articles found by RefScout 48/2004 -24/11/2004

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This is RefScout-Newsletter 48/2004 



REQUEST: [ leishmaniasis ]

(15 articles match this request. 2 articles matching other requests removed)



PMID: 15550258
 

TITLE: A new PCR-ELISA for diagnosis of visceral leishmaniasis in blood of
HIV-negative subjects.

AUTHORS: Simonne De Doncker, Veronik Hutse, Saïd Abdellati, Suman Rijal, Bal
Man Singh Karki, Saskia Decuypere, Diane Jacquet, Dominique Le Ray, Marleen
Boelaert, Shekhar Koirala, Jean-Claude Dujardin

AFFILIATION: Laboratory of Molecular Parasitology, Prins Leopold Instituut voor
Tropische Geneeskunde, Nationalestraat 155, B-2000 Antwerpen, Belgium.

REFERENCE: Trans R Soc Trop Med Hyg 2005 Jan 99(1):25-31

The PCR-ELISA represents a promising advance for diagnosis of visceral 
leishmaniasis (VL) in blood samples. However, the method has been 
validated mostly with HIV-positive patients who are known to have high 
levels of parasitaemia. We developed a new PCR-ELISA assay for specific 
detection of Leishmania in patients' blood and validated it in Nepalese 
subjects with clinically suspected VL, almost all of whom were HIV-
negative. For blood samples, PCR-ELISA was more sensitive (83.9%) than 
conventional PCR (73.2%), and demonstrated 100% and 87.2% specificity 
when using healthy controls who had never travelled to a VL-endemic area
 and controls from a VL-endemic area as references, respectively. We 
have demonstrated the ability of PCR-ELISA to detect parasites in blood 
of HIV-negative patients. The method could be used for epidemiological 
as well as clinical purposes, as it reduces the need for traumatic bone 
marrow sampling and risky spleen aspiration.








PMID: 15550256
 

TITLE: Atypical cutaneous leishmaniasis in Central America: possible
interaction
between infectious and environmental elements.

AUTHORS: J Convit, M Ulrich, M Pérez, J Hung, J Castillo, H Rojas, A Viquez, L
N Araya, H De Lima

AFFILIATION: Instituto de Biomedicina, Universidad Central de
Venezuela/Ministerio de Salud y Desarrollo Social, Apartado 4043, Caracas
1010A, Venezuela.

REFERENCE: Trans R Soc Trop Med Hyg 2005 Jan 99(1):13-7

Biopsies of 71 cases of atypical cutaneous leishmaniasis from Costa 
Rican patients were evaluated by histopathological procedures and 
attempts were made to culture Leishmania from nine biopsies. Leishmanin 
skin tests were carried out in 31 patients and 112 healthy individuals. 
Additional biopsies from 19 patients from Nicaragua were evaluated by 
routine histopathology. Ten biopsies were studied by confocal and nine 
by scanning electron microscopy. Inorganic material was analysed using 
an electron probe for microanalysis. Leishmania parasites were isolated 
from only two biopsies, but 90.3% of the patients from Costa Rica were 
leishmanin-positive, as were 27.7% of healthy individuals. Routine 
histopathological studies revealed naked granulomas formed by 
differentiated macrophages. Abundant inorganic material was observed in 
sections examined by confocal microscopy. Electron probe analysis 
revealed that silica and aluminium were the predominant elements in 
large particles. We postulate that the presence of this inorganic 
material, possibly of volcanic origin, in the skin may modulate the 
immunological response to Leishmania and may inhibit visceralization in 
the cases caused by Leishmania chagasi.




PMID: 15550262
 

TITLE: Risk factors for mucosal manifestation of American cutaneous
leishmaniasis.

AUTHORS: George L L Machado-Coelho, Waleska T Caiaffa, Odair Genaro, Paulo A
Magalhães, Wilson Mayrink

AFFILIATION: Department of Pharmacy, Federal University of Ouro Preto, Rua
Costa
Sena 171, 35400-000 Ouro Preto, MG, Brazil.

REFERENCE: Trans R Soc Trop Med Hyg 2005 Jan 99(1):55-61

A case-comparison study was carried out to identify risk factors for 
mucosal manifestations of American cutaneous leishmaniasis (ACL) in 
southeast Brazil, using a series of 2820 patients, diagnosed with ACL 
between 1966 and 1999. The significant factors independently associated 
with mucosal leishmaniasis were: gender, age, nutritional status and 
length of disease. Mucosal leishmaniasis occurred 1.7 times more 
frequently among males than females; twice as often in individuals older
 than 22 years compared with the younger group; almost four times as 
often in individuals with severe malnutrition compared with those who 
were well nourished; and almost four times more frequently in 
individuals reporting the disease for more than 4 months compared with 
those reporting a shorter duration of the disease. Among individuals 
older than 22 years the risk of mucosal leishmaniasis increased 
significantly (from 1.9 to 9.6) as the nutritional status decreased, 
when compared with younger and well-nourished patients. The 
characteristics herein described and correlated with severe forms could 
be used as diagnostic markers as part of clinical screening in areas 
endemic for ACL.




PMID: 15546090
 

TITLE: Oral Miltefosine for Leishmaniasis in Immunocompromised Patients:
Compassionate Use in 39 Patients with HIV Infection.

AUTHORS: Herbert Sindermann, Kirsten R Engel, Christina Fischer, Wolfgang
Bommer, 

AFFILIATION: Medical Research and Development, Zentaris, Frankfurt am Main,
Germany. herbert.sindermann at zentaris.com.

REFERENCE: Clin Infect Dis 2004 Nov 39(10):1520-3

Oral miltefosine was administered to 39 human immunodeficiency virus (
HIV)-infected patients with leishmaniasis for whom standard 
leishmaniasis treatment had failed. Initial response was achieved in 25 
patients (64%), including 16 patients (43%) with initial parasitological
 cure. Repeated responses after relapse and tolerability of long courses
 of treatment indicate the potential for development of optimized dosage
 schemes.




PMID: 14513375
 

TITLE: Miltefosine (Impavido): the first oral treatment against leishmaniasis.

AUTHORS: H Sindermann, S L Croft, K R Engel, W Bommer, H J Eibl, C Unger, J
Engel

AFFILIATION: Zentaris AG, Weismüllerstrasse 45, 60314, Frankfurt am Main,
Germany.

REFERENCE: Med Microbiol Immunol (Berl) 2004 Nov 193(4):173-80

Miltefosine is a novel antileishmanial drug that has significant 
selectivity in both in vitro and in vivo models. Clinical efficacy was 
demonstrated for the treatment of visceral leishmaniasis with the 
advantage of oral administration over the currently recommended 
antileishmanial drugs that require parenteral administration. 
Miltefosine produces high cure rates also in patients resistant to the 
standard antimonial therapy.








PMID: 15551719
 

TITLE: Leishmaniasis acquired in the Iraqi Theater of Operations: lessons
learned.

AUTHORS: Dirk M Elston, Scott D Miller

AFFILIATION: Departments of Dermatology and Laboratory Medicine, Geisinger
Medical Center, 100 N Academy Ave, Danville, PA 17822-1406, USA.
delston at geisinger.edu

REFERENCE: Cutis 2004 Oct 74(4):253-5

Between August 2002 and February 2004, the Department of Defense 
identified 522 cases of cutaneous leishmaniasis in military personnel. 
This commentary examines reasons why there were so many cases of 
leishmaniasis during this conflict as compared with Operation Desert 
Storm. Lessons learned can be applied to reduce the risk to US personnel
 during future conflicts. Among the factors to be considered are 
environment, exposure, vector control, and the failure to deliver insect
 repellent to deployed US personnel.




PMID: 15543683
 

TITLE: A role for insect galectins in parasite survival.

AUTHORS: Shaden Kamhawi, Marcelo Ramalho-Ortigao, Van M Pham, Sanjeev Kumar,
Phillip G Lawyer, Salvatore J Turco, Carolina Barillas-Mury, David L Sacks,
Jesus G Valenzuela

AFFILIATION: Laboratory of Parasitic Diseases, National Institutes of Allergy
and Infectious Diseases, NIH, Bethesda, MD 20892, USA.

REFERENCE: Cell 2004 Oct 119(3):329-41

Insect galectins are associated with embryonic development or immunity 
against pathogens. Here, we show that they can be exploited by parasites
 for survival in their insect hosts. PpGalec, a tandem repeat galectin 
expressed in the midgut of the sandfly Phlebotomus papatasi, is used by 
Leishmania major as a receptor for mediating specific binding to the 
insect midgut, an event crucial for parasite survival, and accounts for 
species-specific vector competence for the most widely distributed form 
of cutaneous leishmaniasis in the Old World. In addition, these studies 
demonstrate the feasibility of using midgut receptors for parasite 
ligands as target antigens for transmission-blocking vaccines.




PMID: 15551883
 

TITLE: [Role of Langerhans cells in the immunity of leishmaniasis]

AUTHORS: Milena Zuluaga, Sara María Robledo

AFFILIATION: Programa de Estudio y Control de Enfermedades Tropicales, PECET,
Corporación Académica para el Estudio de Patologías Tropicales, Universidad
de Antioquia, Medellín, Colombia.

REFERENCE: Biomedica 2004 Sep 24(3):302-17

Immune response induced against Leishmania parasites is influenced by 
several factors, one of the most important being the type of Antigen 
Presenting Cell (APC). Langerhans cells, a subpopulation of APC, are 
sentinel cells for detecting invader microorganisms; they reside in skin
 tissues at levels where the phlebotomine fly vector inoculates 
Leishmania parasites. Presence of microorganisms can induce activation 
of Langerhans cells, leading to their maturation and migration towards 
lymph nodes. There, Langerhans cells present antigens to T cells for 
their subsequent activation and specific differentiation into effector 
cells. Early after a Leishmania infection, few T cells have been 
observed at sites of infection, suggesting that infected macrophages 
have little opportunity to locate T cells specific for elimination of 
Leishmania parasites. However, Langerhans cells may be the cells 
available to provide signals for the stimulation of parasite-specific T-
cell responses in the lymph node and for inducing T-cell migration to 
the infected skin. Herein, the main characteristics of Langerhans cells 
are reviewed, with special emphasis on their participation in cutaneous 
inflammatory response. The role of these cells in infections caused by 
protozoan parasites of the Leishmania genus is discussed.




PMID: 15523248
 

TITLE: [Subacute Mediterranean visceral leishmaniosis treated with a single
injection of amphotericin B]

AUTHORS: F Vandenbos, P Marty, E Rosenthal, P Delaunay, P Dellamonica, Y Le
Fichoux

REFERENCE: Presse Med 2004 Sep 33(15):1009-10








PMID: 15545130
 

TITLE: Dacryocystectomy: indications and results.

AUTHORS: Suzana Matayoshi, Alfred Van Baak, Alexandra Cozac, Mariluze Sardinha,
José Byron Vicente Dias Fernandes, Euripedes da Mota Moura

AFFILIATION: Department of Ophthalmology and Otorhinolaryngology University of
São Paulo School of Medicine São Paulo Brazil.

REFERENCE: Orbit 2004 Sep 23(3):169-73

BACKGROUND After the advent of dacryocystorhinostomy (DCR), 
dacryocystectomy (DCT) was regarded as mutilant surgery and reserved for
 lacrimal sac tumors. PURPOSE To present current indications for 
dacryocystectomy. METHODS Eighteen eyes from 11 patients subjected to 
DCT were reviewed retrospectively. Nine patients had chronic 
dacryocystitis confirmed by dacryocystography and two patients had 
lacrimal sac tumors. RESULTS The indications for DCT were: three 
patients with systemic medical problems, three patients with dry eye, 
two cases of lacrimal sac tumors, two cases of traumatic dacryocystitis 
and one case of cutaneous leishmaniasis. Dacryocystitis was resolved in 
17 of 18 eyes; the two cases of tumor evolved without epiphora. One 
patient (traumatic dacryocystitis) had recurrence of dacryocystitis. 
CONCLUSIONS DCT is mainly performed when a lacrimal sac tumor is 
suspected but, since it avoids the intra- and postoperative 
complications related to dacryocystorhinostomy, it can be indicated in 
cases of dacryocystitis with significant lacrimal discharge and an 
enlarged or altered lacrimal sac.




PMID: 15543410
 

TITLE: Phlebotomine sand flies in Porteirinha, an area of American visceral
leishmaniasis transmission in the State of Minas Gerais, Brazil.

AUTHORS: Ricardo Andrade Barata, João Carlos França da Silva, Roberto Teodoro
da Costa, Consuelo Latorre Fortes-Dias, Jaime Costa da Silva, Edvá Vieira de
Paula, Aluízio Prata, Erika Michalsky Monteiro, Edelberto Santos Dias

AFFILIATION: Centro de Pesquisas René Rachou-Fiocruz, Av. Augusto de Lima
1715,
30190-002, Belo Horizonte, MG, Brazil.

REFERENCE: Mem Inst Oswaldo Cruz 2004 Aug 99(5):481-7

A study of the phlebotomine sand fly fauna was carried out in an endemic
 area of American visceral leishmaniasis (AVL) in the municipality of 
Porteirinha, in the Brazilian state of Minas Gerais. Captures were 
performed with CDC light traps in 7 districts, 5 days per month, during 
2 consecutive years (January 2000 to December 2001). A total of 3240 
sand flies were captured and identified. Sixteen species were found, 
among which 15 belonged to the genus Lutzomyia and one to the genus 
Brumptomyia. Lutzomyia longipalpis, a proven vector of AVL, was the 
predominant species (71.85%) throughout the time period. The 
interference of climatic factors (temperature, humidity, and rainfall) 
over the populational dynamics of the sand flies was determined. 
Statistical analysis of the data showed a significant correlation among 
the number of phlebotomine sand flies collected, rainfall, and humidity
, whereas the effect of temperature was negligible, in that particular 
region. The amount of collected phlebotomine, the number of human cases
, and the prevalence of canine AVL in the districts of Porteirinha are 
discussed.




PMID: 15543418
 

TITLE: Antileishmanial IgG and IgE antibodies recognize predominantly
carbohydrate epitopes of glycosylated antigens in visceral leishmaniasis.

AUTHORS: A M Atta, R Colossi, M L B Sousa-Atta, S M B Jeronimo, M D S B
Nascimento, G F Bezerra, G Orge, E M Carvalho

AFFILIATION: Laboratório de Pesquisa em Imunologia, Departamento de Análises
Clínicas e Toxicológicas, Faculdade de Farmácia, Universidade Federal da
Bahia, Rua Barão de Geremoabo s/no, Campus de Ondina, 40171-970 Salvador, BA,
Brazil. ajatta at ig.com.br

REFERENCE: Mem Inst Oswaldo Cruz 2004 Aug 99(5):525-30

The specificity of human antileishmanial IgG and IgE antibodies to 
glycosylated antigens of Leishmania chagasi was evaluated. An ELISA was 
performed with soluble leishmanial antigen (SLA) and a panel of 95 sera 
including samples from patients with subclinical infection (SC) and 
visceral leishmaniasis (VL), subjects cured of visceral leishmaniasis (
CVL), and from healthy individuals from endemic areas (HIEA). 
Antileishmanial IgG were verified for 18 (40%) of 45 SC subjects (mean 
absorbance of 0.49 +/- 0.17). All nine sera from VL patients had such 
antibody (0.99 +/- 0.21), while 11 (65%) of 17 CVL individuals were 
seropositive (0.46 +/- 0.05). Only three (12%) of 24 HIEA controls 
reacted in IgG-ELISA. Antileishmanial IgE was detected in 26 (58%) of 45
 SC patients (0.35 +/- 0.14), and in all VL patients (0.65 +/- 0.29). 
These antibodies were also detected in 13(76%) of 17 CVL subjects (0.42
 +/- 0.14) while all HIEA controls were seronegative. There was no 
correlation between antileishmanial IgG and IgE antibody absorbances. 
Mild periodate oxidation at acid pH of SLA carbohydrates drastically 
diminished its antigenicity in both IgG and IgE-ELISA, affecting mainly 
the antigens of 125, 102, 94, and 63 kDa as demonstrated by western 
immunoblotting.




PMID: 15544717
 

TITLE: Itraconazole Can be Effective in the Treatment of Sporotrichoid
Leishmaniasis.

AUTHORS: Paola Morelli, Erika Gianelli, Sara Calattini, Mario Corbellino,
Spinello Antinori, Luca Meroni

AFFILIATION: Department of Infectious and Tropical Diseases, University of
Milan, L. Sacco Hospital, Milan, Italy.

REFERENCE: J Travel Med 2004 Sep-Oct 11(5):328-30

Leishmaniasis represents a diverse group of diseases caused by protozoan
 parasites that are transmitted to humans by the bite of phlebotomine 
sandflies. Three major clinical forms can be recognized, visceral, 
cutaneous and mucocutaneous, which are widespread in tropical, 
subtropical and temperate areas.1.




REQUEST: [ leishmania ]

(10 articles match this request. 5 articles matching other requests removed)



PMID: 15546389
 

TITLE: The role of IL-27 in the development of T-cell responses during
parasitic
infections.

AUTHORS: Christopher A Hunter, Alejandro Villarino, David Artis, Phillip Scott

AFFILIATION: Department of Pathobiology, University of Pennsylvania School of
Veterinary Medicine, Philadelphia, PA, USA.

REFERENCE: Immunol Rev 2004 Dec 202():106-14

Summary: The recognition that CD4(+) T-cell responses could be divided 
into at least two functional subsets either dominated by production of 
interferon (IFN)-gamma and associated with cell-mediated immunity (Th1) 
or characterized by production of interleukin (IL)-4 and IL-5 and 
associated with humoral immunity (Th2) provided a basis to understand 
the role of T cells in resistance or susceptibility to different types 
of pathogens. As a consequence, many studies have focused on the 
identification of cytokines that influence these events. For example, 
the development of Th1-type responses is largely dependent on IL-12. 
However, other cytokines also affect this process, and initial studies 
revealed that IL-27, a cytokine with close structural and functional 
similarity to IL-12, can promote Th1 responses required for immunity to 
Leishmania major. Subsequent work with IL-27R (WSX-1)-deficient mice 
infected with Toxoplasma gondii or Trypanosoma cruzi revealed that the 
IL-27/IL-27R system can act as a negative regulator of inflammatory T-
cell responses. The aim of this review is to discuss recent studies from
 these laboratories on the role of IL-27 in immunity to parasitic 
infections in the context of previous work and to highlight the 
pleiotropic effects of the IL-27/IL-27R system in the development and 
regulation of Th1 and Th2 responses.








PMID: 15516924
 

TITLE: Deletion of a conserved Il4 silencer impairs T helper type 1-mediated
immunity.

AUTHORS: K Mark Ansel, Rebecca J Greenwald, Suneet Agarwal, Craig H Bassing,
Silvia Monticelli, Jeneen Interlandi, Ivana M Djuretic, Dong U Lee, Arlene H
Sharpe, Frederick W Alt, Anjana Rao

AFFILIATION: [1] Department of Pathology, Harvard Medical School, Boston,
Massachusetts 02115, USA. [2] CBR Institute for Biomedical Research, Boston,
Massachusetts 02115, USA.

REFERENCE: Nat Immunol 2004 Dec 5(12):1251-9

Helper T cell differentiation involves silencing as well as activation 
of gene expression. We have identified a conserved silencer of the gene 
encoding interleukin 4 (Il4) marked by DNase I hypersensitivity (HS IV) 
and permissive chromatin structure in all helper T cells. Deletion of HS
 IV increased Il4 and Il13 transcription by naive T cells and led to T 
helper type 2 skewing in vitro. HS IV controlled Il4 silencing during T 
helper type 1 differentiation, as HS IV-deficient T helper type 1 cells 
that expressed interferon-gamma also produced abundant interleukin 4 in 
vitro and in vivo. Despite mounting a vigorous interferon-gamma response
, HS IV-deficient mice were more susceptible to Leishmania major 
infection than were wild-type littermate control mice, showing a 
critical function for Il4 silencing in T helper type 1-mediated immunity.




PMID: 15550118
 

TITLE: Novel adjuvant based on a proteoliposome-derived cochleate structure
containing native lipopolysaccharide as a pathogen-associated molecular
pattern.

AUTHORS: Oliver Pérez, Gustavo Bracho, Miriam Lastre, Nestor Mora, Judith Del
Campo, Danay Gil, Caridad Zayas, Reinaldo Acevedo, Domingo González, José A
López, Carlos Taboada, Rosa L Solis

AFFILIATION: Finlay Institute, Havana, Cuba.

REFERENCE: Immunol Cell Biol 2004 Dec 82(6):603-10

Summary Proteoliposomes (PL) from Neisseria meningitidis B have been 
widely used as a core antigen for antimeningococcal vaccination. PL 
contain major outer membrane proteins, LPS and phospholipids, and they 
induce a strong Th1 immune response, but they have low stability in 
solution. Attending to the need for new vaccine adjuvants, we developed 
a highly stable cochleate structure (CS) from PL using a technology that
 allows easy incorporation of new antigens. We explored the ability of 
PLCS to activate the immune system and its possible application as an 
adjuvant for parenteral and mucosal routes. Our results showed that PLCS
 were able to upregulate the expression of MHC class II and 
costimulatory molecules on human dendritic cells, as well as being able 
to stimulate the production of soluble mediators of a Th1 response, such
 as IL-12 and nitric oxide. High levels of anti-PL IgG were detected in 
serum after i.m. or mucosal (oral and nasal) administration, but also 
anti-PL secretory IgA was produced in saliva following nasal delivery. 
The immune response polarization to a Th1 pattern was confirmed by the 
induction of IgG2a antibodies, positive delayed type hypersensitivity 
reactions, and IFN-gamma production by splenocytes from immunized mice. 
The adjuvant potential was explored using PLCS containing ovalbumin (Ova
). PLCS-Ova was able to elicit a substantial increase in anti-Ova IgG 
compared with Ova alone. In addition, a significant reduction in lesion 
size was observed in mice immunized with Leishmania major antigens in 
PLCS after challenge with virulent protozoa, suggesting at least partial
 modulation of the Th2 environment induced by this parasite. In 
conclusion, our results support the use of PLCS as a potent Th1 adjuvant
 for parenteral and mucosal vaccines.




PMID: 15503007
 

TITLE: Hyper IgE in New Zealand black mice due to a dominant-negative CD23
mutation.

AUTHORS: Graham Lewis, Eleni Rapsomaniki, Tiphaine Bouriez, Tanya Crockford,
Helen Ferry, Robert Rigby, Timothy Vyse, Teresa Lambe, Richard Cornall

AFFILIATION: Nuffield Department of Medicine, John Radcliffe Hospital, Oxford
University, Headington, OX3 9DU, Oxford, UK.

REFERENCE: Immunogenetics 2004 Nov 56(8):564-71

Immunoglobulin E (IgE) plays a critical role in both resistance to 
parasitic infection and allergy to environmental antigens. The IgE 
response is in turn regulated by the B-cell co-receptor CD23, and CD23-
deficient mice show exaggerated IgE responses and airway hyper-
responsiveness. In this report, we show that New Zealand black (NZB) 
mice express a variant CD23 allele, with mutations in both the C-lectin-
binding domain and stalk region, which fails to bind IgE at high 
affinity and has reduced expression on the cell surface. Expression of 
the variant CD23 chain interferes with trimerisation of the receptor and
 has a dominant-negative effect leading to reduced IgE binding in 
crosses between NZB and other strains. Genetic mapping shows that the 
variant CD23 leads to an exaggerated primary IgE response, which is 
independent of other strain-specific effects. These results suggest that
 NZB mice or mice carrying the variant allele will be useful models for 
studying both allergy and quantitative traits associated with atopy. The
 exaggerated IgE response provides an explanation for the natural 
resistance of NZB mice to parasitic infection by Leishmania.




PMID: 15544167
 

TITLE: The heat shock protein HSP70 and heat shock cognate protein HSC70
contribute to antimony tolerance in the protozoan parasite leishmania.

AUTHORS: Christian Brochu, Anass Haimeur, Marc Ouellette

AFFILIATION: Centre de Recherche en Infectiologie du Centre de Recherche du
CHUL
and Division de Microbiologie, Faculté de Médecine, Université Laval, CHUQ,
Pavilion CHUL, 2705, Boulevard Laurier, Sainte-Foy, Québec, Canada.

REFERENCE: Cell Stress Chaperones 2004 Autumn 9(3):294-303

Antimony-containing drugs are still the drugs of choice in the treatment
 of infections caused by the parasite Leishmania. Resistance to antimony
 is now common in some parts of the world, and several mechanisms of 
resistance have been described. By transfecting cosmid banks and 
selecting with potassium antimonyl tartrate (SbIII), we have isolated a 
cosmid associated with resistance. This cosmid contains 2 copies of the 
heat shock protein 70 (HSP70) and 1 copy of the heat shock cognate 
protein 70 (HSC70). Several data linked HSP70 to antimony response and 
resistance. First, several Leishmania species, both as promastigotes and
 amastigotes, increased the expression of their HSP70 proteins when 
grown in the presence of 1 or 2 times the Effect Concentration 50% of 
SbIII. In several mutants selected for resistance to either SbIII or to 
the related metal arsenite, the HSP70 proteins were found to be 
overexpressed. This increase was also observed in revertant cells grown 
for several passages in the absence of SbIII, suggesting that this 
increased production of HSP70 is stable. Transfection of HSP70 or HSC70 
in Leishmania cells does not confer resistance directly, though these 
transfectants were better able to tolerate a shock with SbIII. Our 
results are consistent with HSP70 and HSC70 being a first line of 
defense against SbIII until more specific and efficient resistance 
mechanisms take over.




REQUEST: [ sand fly ]

(2 articles match this request. 1 article matching other requests removed)



PMID: 15552057
 

TITLE: Paleoleishmania proterus n. gen., n. sp., (Trypanosomatidae:
Kinetoplastida) from cretaceous Burmese amber.

AUTHORS: George Poinar, Roberta Poinar

AFFILIATION: Department of Zoology, Oregon State University, Corvallis, Oregon
97331, USA. poinarg at science.oregonstate.edu

REFERENCE: Protist 2004 Sep 155(3):305-10

A trypanosomatid (Trypanosomatidae: Kinetoplastida) associated with a 
blood-filled female sand fly in Cretaceous Burmese amber, is described 
in the new genus and species, Paleoleishmania proterus. The genus 
Paleoleishmania is established as a collective genus for digenetic 
fossil trypanosomes associated with sand flies. Amastigotes, 
promastigotes and paramastigotes are described. Paleoleishmania proterus
 is the first fossil kinetoplastid and provides a minimum age for the 
digenetic Trypanosomatidae. Its discovery indicates that vector-borne 
pathogens had been established by the Early Cretaceous.




REQUEST: [ sandfly ]

(1 article matches this request. 1 article matching other requests removed)














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