[leish-l] Fwd: Articles found by RefScout 17-Nov-04/472004
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Wed Nov 17 12:13:11 BRST 2004
Date: Wed, 17 Nov 2004 01:44:34
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This is RefScout-Newsletter 47/2004
REQUEST: [ leishmaniasis ]
(15 articles match this request)
PMID: 15533290
TITLE: Species co-occurrence and feeding behavior in sand fly transmission of
American cutaneous leishmaniasis in western Venezuela.
AUTHORS: Luis Fernando Chaves, Nestor Añez
AFFILIATION: Laboratorio de BiologÃa Teórica, Instituto de ZoologÃa Tropical,
Facultad de Ciencias, Universidad Central de Venezuela, Apartado 47058, Caracas
1041-A, Venezuela.
REFERENCE: Acta Trop 2004 Nov 92(3):219-24
The structure of the Phlebotomine sand fly community from the Venezuelan
Andes was studied using null-model tests. The analyses, at the living
zones and altitudes scales, revealed C-scores larger than those expected
by random, independently of the collection technique (P < 0.05).
These results imply that sand fly species are non-aggregated at both
scales. Random results for the variance of C-score and for the favored
states hypothesis suggest that sand fly species belong to an unique
guild. The latter is reinforced by the fact that anthropophilic and
zoophilic species use in the same way a common resource (blood). Finally
, we suggest additional approaches to study the role of the sand fly
community structure on the genesis and dynamics of transmission of
American cutaneous leishmaniasis.
PMID: 15533294
TITLE: Mathematical modelling of American Cutaneous Leishmaniasis: incidental
hosts and threshold conditions for infection persistence.
AUTHORS: Luis Fernando Chaves, Maria-Josefina Hernandez
AFFILIATION: Laboratorio de BiologÃa Teórica & Postgrado en EcologÃa,
Instituto de ZoologÃa Tropical, Facultad de Ciencias, Universidad Central de
Venezuela, Apartado Postal 47058, Caracas 1041-A, Venezuela.
REFERENCE: Acta Trop 2004 Nov 92(3):245-52
We present a model for the dynamics of transmission of American
Cutaneous Leishmaniasis (ACL) that includes a population of incidental
hosts for parasites (that is, they act only as sinks of infection),
along with species that are reservoir hosts (that is, both source and
sink of infection). Although, there is evidence that suggests the
existence of incidental hosts for Leishmania parasites, there are no
mathematical models developed to account for this. Based on this model
we obtained expressions that allow computing the threshold conditions
for the persistence of the infection using three different approaches.
The three expressions agree in the parameters involved in the
computation of the threshold, and also in the parameters that are
excluded from it, which are those related to the transmission in
incidental hosts. We also suggest alternatives for future development in
the modelling of the dynamics of transmission of ACL, according to the
needs of a more realistic, precise, or general character of the model.
PMID: 15533299
TITLE: Rapid clearance of circulating Leishmania kinetoplast DNA after treatment
of visceral leishmaniasis.
AUTHORS: Jolande Disch, Maria Cláudia Oliveira, Marcela Orsini, Ana Rabello
AFFILIATION: Laboratório de Pesquisas ClÃnicas, Centro de Pesquisas René
Rachou-FIOCRUZ. Av. Augusto de Lima, 1715, 30190-002, Belo Horizonte, MG,
Brazil.
REFERENCE: Acta Trop 2004 Nov 92(3):279-83
With the aim of evaluating the utility of the detection of Leishmania
kDNA in peripheral blood for the cure assessment of visceral
leishmaniasis (VL), a PCR based method was performed in patients with
confirmed VL at three follow-up periods after specific chemotherapy with
pentavalent antimonial. In 16 out of 17 (94.1%) patients with pre-
treatment detectable kDNA that were clinically cured, the PCR turned
negative up to 37 days after the initiation of treatment, remaining
negative over 90 days after treatment. The clearance of Leishmania kDNA
from peripheral blood of patients with VL hints to occur during or
shortly after treatment concurring or preceding clinical recovery.
PMID: 15533066
TITLE: Atypical clinical form of cutaneous leishmaniasis: erysipeloid form.
AUTHORS: Yelda Karincaoglu, Muammer Esrefoglu, Hamdi Ozcan
AFFILIATION: From the Department of Dermatology, Inonu University, School of
Medicine, Turgut Ozal Medical Center, Malatya, Turkey.
REFERENCE: Int J Dermatol 2004 Nov 43(11):827-9
A 60-year-old woman was admitted to our clinic with a gradually
enlarging red papule on her face. Her history revealed that, 9 months
previously, a painless, red papule of 1-2 cm in diameter had occurred in
the middle of her face and, with time, had enlarged to cover her nose,
both cheeks, and eyelids. It was diagnosed as a superficial skin
infection, and topical and systemic antibiotics were prescribed; however
, no response was obtained. In the last 2 months, a sore had formed in
the middle of her nose. The patient lives in the east of Eastern
Anatolia, where no case of cutaneous leishmaniasis has been reported in
the last 20 years. On dermatologic examination of the patient, an
erythematous, indurated, slightly squamous, 10 cm x 5 cm, butterfly-
shaped plaque with sharply defined borders was seen on both cheeks,
lower eyelids, and the whole nose (Fig. 1). In smears taken from the
lesion, a number of amastigotes belonging to Leishmania were determined
in the intracellular and extracellular area (Fig. 2). Histopathologic
examination of the cutaneous lesion showed scattered infiltration
composed of mononuclear cells, histiocytes, plasma cells, and small
epithelioid granulomas. Gram smear and anaerobe-aerobe culture prepared
from the lesion were negative. The total blood count and sedimentation
rate of the patient were within normal limits. Routine biochemical tests
, urine analysis, chest radiography, and intradermal purified protein
derivative (PPD) skin test were all normal. Antinuclear antibody and
antistreptolysin antibody examinations were negative. The patient was
treated intramuscularly with 10 mg/kg/day systemic meglumine antimoniate
, divided into two doses, for 20 days, with good control.
PMID: 15533064
TITLE: A quantitative study of epidermal Langerhans cells in cutaneous
leishmaniasis caused by Leishmania tropica.
AUTHORS: Simin Meymandi, Shahriar Dabiri, Darya Dabiri, Richard I Crawford,
Arsalan Kharazmi
AFFILIATION: From the Departments of Dermatology and Pathology, Afzalipour
Medical School, Kerman, Iran.
REFERENCE: Int J Dermatol 2004 Nov 43(11):819-23
Abstract Objective The purpose of this study was to characterize the
number and distribution of epidermal Langerhans cells in different
clinical forms of dry-type cutaneous leishmaniasis (CL). Methods Sixteen
cases of dry-type cutaneous leishmaniasis caused by Leishmania tropica
were studied. These cases were classified clinically as five cases of
acute leishmaniasis with indurated papules, nodules and plaques with
central crust formation and duration < 2 years, six cases of lupoid
leishmaniasis with characteristic papules around previous scars of
cutaneous leishmaniasis with duration > 2 years, and five cases of
chronic nonlupoid type with nonhealing lesions of duration > 2 years.
Paraffin-embedded blocks were stained with hematoxylin and eosin (H&
E) and stained immunohistochemically for CD1a. Results The number of
Langerhans cells per millimeter length of epidermis was increased in
acute cases compared to chronic and lupoid cases. Conclusions Lesions of
acute leishmaniasis contain the greatest amounts of antigen for
presentation, so Langerhans cells increase in number and in trafficking
to present antigens derived from Leishman bodies to the cellular immune
system. In chronic leishmaniasis, the Langerhans cell population is
reduced, perhaps because of exhaustion of the source of Langerhans cells
, or because of reduced response to modified antigen.
PMID: 15535606
TITLE: Commentary to, "Phlebotomine sand flies (Diptera: Psychodidae) of the
Palestinian West Bank: potential vectors of leishmaniasis," by Samir S.
Sawalha, Muhamad S. Shtayeh, Haroun M. Khanfar, Alon Warburg, and Ziad A.
Abdeen, J. Med. Entomol. 40: 321-328.
AUTHORS: Jérôme Depaquit, Nicole Léger
REFERENCE: J Med Entomol 2004 Sep 41(5):813
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, AluÃzio Prata, Erika Michalsky Monteiro, Edelberto Santos Dias
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: Am Atta, R Colossi, Mlb Sousa-Atta, Smb Jeronimo, Mdsb Nascimento, Gf
Bezerra, G Orge, Em Carvalho
AFFILIATION: Laboratório de Pesquisa em Imunologia, Departamento de Análises
ClÃnicas e Toxicológicas, Faculdade de Farmácia, Universidade Federal da
Bahia, Salvador, BA, 40171-970, Brasil.
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: 15533763
TITLE: Leishmaniasis: drugs in the clinic, resistance and new developments.
AUTHORS: Marc Ouellette, Jolyne Drummelsmith, Barbara Papadopoulou
AFFILIATION: Centre de Recherche en Infectiologie du Centre de Recherche du CHUL
and Division de Microbiologie, Faculté de Médecine, Université Laval, Que.,
Canada G1V 4G2.
REFERENCE: Drug Resist Updat 2004 Jul-Aug 7(4-5):257-66
The control of Leishmania infections relies primarily on chemotherapy.
The arsenal of drugs available for treating Leishmania infections is
limited and includes pentavalent antimonials, pentamidine, amphotericin
B, miltefosine, fluconazole and few other drugs at various stages of
their development process. In this review, we will discuss the latest
results regarding resistance mechanisms to drugs used in the clinic
against Leishmania infections.
PMID: 15530296
TITLE: Childhood leishmaniasis: report of 106 cases.
AUTHORS: Monia Kharfi, Rym Benmously, Nadia El Fekih, Meriem Daoud, Zohra
Fitouri, Inçaf Mokhtar, Saïda Ben Becher, Mohamed Ridha Kamoun
AFFILIATION: Dermatology Department, Charles Nicolle Hospital, Tunis, Tunisia.
monia.kharfi at rns.tn
REFERENCE: Dermatol Online J 2004 10(2):6
In Tunisia there are three epidemic clinical forms of cutaneous
leishmaniasis. They are associated with three different species of
Leishmania and are observed in different geographical areas. We
undertook a single-center retrospective analysis of childhood
leishmaniasis in order to describe epidemio-clinical profile,
therapeutic characteristics and clinical outcomes of affected patients.
The study comprises 166 children with 132 lesions of cutaneous
leishmaniasis. The subjects ages range from 5 months to 15 years (
average 8.75 years). The F:M sex ratio is 1.3. Leishmaniasis affects
grown-up children in 74.5 percent of the cases. All of our patients live
in an endemic area. The face is affected in 76.5 percent of cases.
Mucosal leishmaniasis is present in 9 children (6.8 %). Clinical
diagnosis confirmed by the parasitologic smear or histopathological
examination in 89.6 percent of the cases. Treatment with intralesional
meglumine antimoniate is done for 67 patients; the treatment regimen is
one local injection (1 ml/cm(2)) per week until recovery. Systemic
meglumine antimoniate is the initial therapy for 25 patients. Meglumine
antimoniate treatment is well tolerated with no side-effects. All
leishmaniasis lesions heal within an average period of 2.18 months.
Childhood cutaneous leishmaniais is common in Tunisia. It has the
characteristics of sporadic leishmaniasis. Mucosal leishmaniasis has a
favorable outcome with no destruction, nor scaring deformity. The
standard treatment remains intralesional meglumine antimoniate.
PMID: 15530311
TITLE: Ulcerated disseminated cutaneous leishmaniasis associated with vitiligo,
hypothyroidism, and diabetes mellitus in a patient with Down syndrome.
AUTHORS: Shahin Aghaei, Rahmat Salmanpour, Farhad Handjani, Ahmad Monabati,
Nazila Mazharinia, Ladan Dastgheib
AFFILIATION: Department of Dermatology, Shiraz University of Medical Sciences,
Shiraz, Iran. shahinaghaei at yahoo.com
REFERENCE: Dermatol Online J 2004 10(2):21
We report a 35-year-old man who was referred to our dermatology
department with multiple, nodular, ulcerated, and crusted lesions
disseminated on the face, trunk, and extremities. He has a known
diagnosis of Down syndrome. The past medical history also included
vitiligo (for 20 years), hypothyroidism (for 2 years), and type-II
diabetes mellitus (for 3 months). Direct smear of an ulcer was positive
for leishmania. Skin biopsy confirmed the diagnosis. A leishmanin skin
test was negative. Polymerase chain reaction (PCR) from two separate
skin biopsies demonstrated the presence of Leishmania major. To our
knowledge, this is the first report of disseminated cutaneous
leishmaniasis (DCL) caused by L. major in Iran, and also the first
report of association between DCL with Down syndrome, vitiligo,
hypothyroidism, and diabetes mellitus.
PMID: 15027690
TITLE: [Epidemiological aspects of leishmaniosis in Italian regions]
AUTHORS: M G Verso, S Caracappa, F Vitale, G Vesco, D Picciotto
AFFILIATION: Istituto di Medicina del Lavoro e Preventiva G. Fradà , Palermo,
Italy.
REFERENCE: G Ital Med Lav Ergon 2003 Oct-Dec 25(4):441-3
The analysis of infectious diseases in Italy and regarding some working
activities has pointed out several cases of leishmaniosis, in various
shapes. Its persistent presence in some endemic areas in our country,
together with possibility of work exposure and in assence of very
sensitive or specific diagnostic methods, represents a problem in
medical practice. It's necessary for physicians and veterinaries take
greater attention about this illness and the other anthropozoonosis,
always actual in some areas and increasing for AIDS's sicks,
representing other infection sources.
PMID: 15535576
TITLE: Colonization of Phlebotomus neglectus (Diptera: Psychodidae), the major
vector of visceral leishmaniasis in Greece.
AUTHORS: B Chaniotis, I Spyridaki, E Scoulika, M Antoniou
AFFILIATION: Laboratory of Clinical Bacteriology, Parasitology, Zoonoses and
Geographic Medicine, Division of Medicine, University of Crete, Iraklion,
Crete, Greece.
REFERENCE: J Med Entomol 2000 May 37(3):346-8
Colonization of Phlebotomus neglectus Tonnoir, the major vector of
visceral leishmaniasis, in Greece is reported for the first time.
Starting with wild-caught specimens, a small closed colony was
established that was maintained for 17 mo or 10 generations. Gonotrophic
discordance, stenogamic mating behavior, low fecundity, and dormancy
because of low temperature were the most important findings that
characterized the colony.
PMID: 15535572
TITLE: Genetic divergence among Venezuelan populations of Lutzomyia longipalpis
(Diptera: Psychodidae: Phlebotominae).
AUTHORS: J Arrivillaga, Y Rangel, M Oviedo, M D Feliciangeli
AFFILIATION: Universidad de Carabobo, Fac de Ciencias de la Salud, BIOMED,
Centro de Referencia Nacional de Flebotomos, La Morita, Apdo 4873.Maracay, Edo.
Aragua Venezuela.
REFERENCE: J Med Entomol 2000 May 37(3):325-30
Lutzomyia longipalpis (Lutz & Neiva) is the primary vector of
visceral leishmaniasis in Venezuela. An analysis of alleles at seven
enzyme-encoding loci among four populations from different geographic
and epidemiological regions revealed strong genetic substructuring.
Isozyme analysis indicated that L. longipalpis in Venezuela is a complex
of at least two subspecies. Possible differences in population size
during their evolutionary histories, varying colonization histories and
geological events may explain discrepancies in the patterns of variation
observed at genetic markers between these four populations.
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PMID: 14641849
TITLE: Control trial of Lutzomyia longipalpis s.l. in the Island of Margarita,
Venezuela.
AUTHORS: M Dora Feliciangeli, Milena B Mazzarri, Sonia San Blas, Olga Zerpa
AFFILIATION: Universidad de Carabobo, Facultad de Ciencias de la Salud, Centro
Nacional de Referencia de Flebótomos, BIOMED, Núcleo Aragua, Maracay,
Venezuela. mdora at telcel.net.ve
REFERENCE: Trop Med Int Health 2003 Dec 8(12):1131-6
The incidence of the American visceral leishmaniasis (AVL) in the Island
of Margarita, a major tourist centre in Venezuela, has been increasing
between 1998 and 2001. Lutzomyia longipalpis s.l. is the recognized
vector, which was found naturally infected with Leishmania spp,
indistinguishable from the parasites recovered from dogs and children.
In 1999-2000, we conducted a control trial in Santa Ana del Valle and
Las Cabreras, which have similar epidemiological and ecological
conditions. The trial was based on intradomestic residual spraying of
lambda-cyhalothrin, E.C., 25 mg/m2 and spatial fogging of fenitrothion
around the houses at 30 g/ha. Sandfly abundance was recorded using
Centers for Disease Control (CDC) traps indoors and outdoors. We found
significantly reduced sandfly populations in the target locality. Wall
bioassays showed that the residual effect of the insecticide lasts for
about 3 months. We believe that indoor spraying with lambda-cyhalothrin
three times a year, at a dose slightly greater than 25 mg/m2, might
reduce the L. longipalpis s.l. population to a level low enough for
achieving a significant reduction of the indoor transmission, thus
protecting small children from the disease.
REQUEST: [ leishmania ]
(16 articles match this request. 9 articles matching other requests removed)
PMID: 15533297
TITLE: Efficacy of trypan((R)): a diminazene based drug as antileishmanial
agent.
AUTHORS: J C Macharia, A J Bourdichon, M M Gicheru
AFFILIATION: Department of Parasitology, Institute of Primate Research, National
Museums of Kenya, P.O. Box 24481, Karen, Nairobi, Kenya.
REFERENCE: Acta Trop 2004 Nov 92(3):267-72
Trypan((R)), a diamidine based drug, was tested as an antileishmanial
agent. Duplicate cultures of both Leishmania major and Leishmania
donovani promastigotes in M199 medium and Trypan((R)) at various
concentrations were tested. The cultures were incubated at 25 degrees C
and parasites counted at 48h interval, and the data generated was used
to establish growth inhibition curves. Drug-free cultures were included
to serve as control. In the in vivo study, a total of 40 BALB/c mice
were divided into five groups of 8 mice each. They were infected with 2
x 10(6) promastogotes on the left footpad. Two groups were treated with
70mug/ml of Trypan((R)), a total of 500mul used immediately after
infection, one group by topical application and the other administered
intraperitoneally. The treatments were repeated for the two other groups
10 weeks post infection, one by topical application and the other
administered intraperitoneally. One group was not treated and thus
served as control. Footpad sizes were measured using Vernier calliper
every 2 weeks for 21 weeks. In the in vitro studies, Trypan((R))
inhibited growth of either L. major or L. donovani promastigotes in all
the concentrations tested with more dramatic inhibition in high
concentrations. Based on the in vivo studies, it was evident that Trypan
((R)) had effect on L. major infected lesions when applied topically
immediately after infection. However, there was no effect when treatment
commenced after the lesions were established. The data is discussed.
PMID: 15322082
TITLE: Leishmania major Elongation Factor 1B Complex Has Trypanothione
S-Transferase and Peroxidase Activity.
AUTHORS: Tim J Vickers, Susan Wyllie, Alan H Fairlamb
AFFILIATION: Division of Biological Chemistry and Molecular Microbiology,
Wellcome Trust Biocentre, School of Life Sciences, University of Dundee,
Dundee, DD1 5EH, Scotland, United Kingdom.
REFERENCE: J Biol Chem 2004 Nov 279(47):49003-9
In the Trypanosomatidae, trypanothione has subsumed many of the roles of
glutathione in defense against chemical and oxidant stress. Crithidia
fasciculata lacks glutathione S-transferase, but contains an unusual
trypanothione S-transferase activity that is associated with eukaryotic
translation elongation factor 1B (eEF1B). Here we describe the cloning,
expression, and reconstitution of the purified alpha, beta, and gamma
subunits of eEF1B from Leishmania major. Individual subunits lacked
trypanothione S-transferase activity. Only eEF1B, formed by
reconstitution or co-expression of the three subunits, was able to
conjugate a variety of electrophilic substrates to trypanothione or
glutathionylspermidine, but not glutathione. In contrast to the C.
fasciculata eEF1B, the L. major enzyme also displayed peroxidase
activity against a variety of organic hydroperoxides. The enzyme showed
no activity with hydrogen peroxide and greatest activity with linoleic
acid hydroperoxide (1 unit mg(-1)). Kinetic studies suggest a ternary
complex mechanism, with K(m) values of 140 mum for trypanothione and 7.4
mm for cumene hydroperoxide and k(cat) = 25 s(-1). Immunofluorescence
studies indicate that the enzyme may be localized to the surface of the
endoplasmic reticulum. These results suggest that, in addition to its
role in protein synthesis, the Leishmania eEF1B may help protect the
parasite from lipid peroxidation.
PMID: 15542100
TITLE: Trypanosomes are monophyletic: evidence from genes for glyceraldehyde
phosphate dehydrogenase and small subunit ribosomal RNA.
AUTHORS: Patrick B Hamilton, Jamie R Stevens, Michael W Gaunt, Jennifer Gidley,
Wendy C Gibson
AFFILIATION: School of Biological Sciences, University of Bristol, Bristol BS8
1UG, UK.
REFERENCE: Int J Parasitol 2004 Nov 34(12):1393-404
The genomes of Trypanosoma brucei, Trypanosoma cruzi and Leishmania
major have been sequenced, but the phylogenetic relationships of these
three protozoa remain uncertain. We have constructed trypanosomatid
phylogenies based on genes for glycosomal glyceraldehyde phosphate
dehydrogenase (gGAPDH) and small subunit ribosomal RNA (SSU rRNA). Trees
based on gGAPDH nucleotide and amino acid sequences (51 taxa) robustly
support monophyly of genus Trypanosoma, which is revealed to be a
relatively late-evolving lineage of the family Trypanosomatidae. Other
trypanosomatids, including genus Leishmania, branch paraphyletically at
the base of the trypanosome clade. On the other hand, analysis of the
SSU rRNA gene data produced equivocal results, as trees either robustly
support or reject monophyly depending on the range of taxa included in
the alignment. We conclude that the SSU rRNA gene is not a reliable
marker for inferring deep level trypanosome phylogeny. The gGAPDH
results support the hypothesis that trypanosomes evolved from an
ancestral insect parasite, which adapted to a vertebrate/insect
transmission cycle. This implies that the switch from terrestrial insect
to aquatic leech vectors for fish and some amphibian trypanosomes was
secondary. We conclude that the three sequenced pathogens, T. brucei, T
. cruzi and L. major, are only distantly related and have distinct
evolutionary histories.
PMID: 15539076
TITLE: Biogenesis of peroxisomes and glycosomes: trypanosomatid glycosome
assembly is a promising new drug target.
AUTHORS: Juliette Moyersoen, Jungwoo Choe, Erkang Fan, Wim G J Hol, Paul A M
Michels
AFFILIATION: Research Unit for Tropical Diseases, Christian de Duve Institute of
Cellular Pathology and Laboratory of Biochemistry, Université Catholique de
Louvain, ICP-TROP 74.39, Avenue Hippocrate 74, B-1200 Brussels, Belgium.
REFERENCE: FEMS Microbiol Rev 2004 Nov 28(5):603-43
In trypanosomatids (Trypanosoma and Leishmania), protozoa responsible
for serious diseases of mankind in tropical and subtropical countries,
core carbohydrate metabolism including glycolysis is compartmentalized
in peculiar peroxisomes called glycosomes. Proper biogenesis of these
organelles and the correct sequestering of glycolytic enzymes are
essential to these parasites. Biogenesis of glycosomes in
trypanosomatids and that of peroxisomes in other eukaryotes, including
the human host, occur via homologous processes involving proteins called
peroxins, which exert their function through multiple, transient
interactions with each other. Decreased expression of peroxins leads to
death of trypanosomes. Peroxins show only a low level of sequence
conservation. Therefore, it seems feasible to design compounds that will
prevent interactions of proteins involved in biogenesis of
trypanosomatid glycosomes without interfering with peroxisome formation
in the human host cells. Such compounds would be suitable as lead drugs
against trypanosomatid-borne diseases.
PMID: 15535620
TITLE: Analysis of the copulatory courtship songs of Lutzomyia longipalpis in
six populations from Brazil.
AUTHORS: Nataly A Souza, Felipe M Vigoder, Alejandra S Araki, Richard D Ward,
Charalambos P Kyriacou, Alexandre A Peixoto
AFFILIATION: Department of Biochemistry and Molecular Biology, Fundação
Oswaldo Cruz, Av. Brasil, 4365, Manguinhos, Rio de Janeiro, RJ 21045-900,
Brazil.
REFERENCE: J Med Entomol 2004 Sep 41(5):906-13
The sand fly Lutzomyia longipalpis Lutz & Neiva (Diptera:
Psychodidae: Phlebotominae), the main vector of Leishmania infantum in
the Americas, is believed to be a species complex, although the status
of different Brazilian populations is still somewhat unclear.
Preliminary analysis of the acoustic signals that are produced during
copulation by L. longipalpis males has suggested the existence of three
sibling species in Brazil. In the current report, we analyze in more
detail a number of parameters of the copulatory courtship songs of L.
longipalpis males from four allopatric populations from different parts
of the country (Marajó Island, Natal, Jacobina, and Lapinha Cave) and
from two sympatric populations from the locality of Sobral, where two
types of males can be differentiated by the number of pale spots (one or
two pairs) found on the abdomen. We show that males from the localities
of Natal, Marajó, and Sobral (two-spot morph) have very similar songs
composed of successive bursts, which are modulated in frequency and
amplitude. No significant differences were found in the song parameters
of these three populations. In contrast, one-spot males from Sobral and
males from Jacobina and Lapinha produce songs that are made of pulses
but with distinct patterns for each population and significant
differences in all song parameters studied. The results suggest that the
L. longipalpis complex in Brazil is composed of four sibling species
and that the differences in song patterns between the populations are
consistent with the level of divergence found in the period gene.
PMID: 15541032
TITLE: Adjuvant guided polarization of the immune humoral response against a
protective multicomponent antigenic protein (Q) from Leishmania infantum. A CpG
+ Q mix protects Balb/c mice from infection.
AUTHORS: N Parody, M Soto, J M Requena, C Alonso
AFFILIATION: Centro de BiologÃa Molecular, CSIC-UAM, Canto Blanco, Madrid,
Spain.
REFERENCE: Parasite Immunol 2004 Jun 26(6-7):283-93
SUMMARY It has been shown that vaccination with three doses of the
Leishmania infantum poly-protein Q containing five genetically fused
antigenic determinants from the Lip2a, Lip2b, H2A and P0 proteins, mixed
with BCG induces clearance of parasites in 9 out of 10 Leishmania
infantum-infected Beagle dogs, in addition to clinical protection. In
the present paper we analysed the immunogenic potential of the poly-
protein Q and the specificity and polarization of the response against
the antigenic determinants of Q when mixed with various adjuvants. The
data showed that the Q protein had high intrinsic immunogenic potential
and that it was able to induce a long-lasting IgG response. The IgM
immunogenic potential of the poly-protein was mainly due to the LiP2a
and LiP2b determinants, whereas the IgG immunogenic potential was mainly
due to the LiP2a component. It was observed that the protein itself
elicited a mixed IgG2a/IgG1 response and that the determinants of Q were
endowed with different IgG2a/IgG1 potential. It was also observed that
the adjuvants did not influence the intensity or specificity of the IgM
response but that they modulated the intensity, the specificity and the
polarization of the IgG response against the determinants of Q. CpG-ODN
motifs or double-stranded DNA plasmids containing CpG motifs when mixed
with Q induced a predominant IgG2a response mainly observed at early
stages post-immunization. The data showed that a CpG + Q mix induced
significant protection against L. infantum infection in Balb/c mice.
PMID: 15535571
TITLE: Photosynthesis modulates the plant feeding of Phlebotomus papatasi
(Diptera: Psychodidae).
AUTHORS: Y Schlein, R L Jacobson
AFFILIATION: Department of Parasitology, the Kuvin Center for the Study of
Infectious and Tropical Diseases, the Hebrew University, Hadassah Medical
School, POB 12272, Jerusalem 91120 Israel.
REFERENCE: J Med Entomol 2000 May 37(3):319-24
Phlebotomus papatasi (Scopoli), the vector of Leishmania major (Yakimoff
& Schokhor), feeds on plants in desert habitats in the Jordan
Valley. At the end of the dry summer, the life span of sand flies is
short and the amount of sugars in their guts is small. In this season
the plants are under the stress of heat and dehydration. This stress
arrests the photosynthesis and decreases the amounts of the main end
products, sucrose and starch. We presumed that the paucity of sugars in
the sand fly plant tissue diet resulted from the arrest of
photosynthesis. To test this assumption, we compared the feeding of sand
flies on branches of Capparis spinosa (L.) that had been kept for 24 h
in darkness and on branches cut after a normal day of photosynthesis. In
darkness, the branches had lost more than half of their sugar content.
Afterward they were fed upon overnight by 45.2% of female and 14.3% of
male sand flies. A higher proportion of 81.0% females and 38.7% males
fed on branches from natural conditions and these fed flies were
significantly heavier. Laboratory experiments also showed that plant
tissue meals of P. papatasi often include starch grains. Such grains
were found also in 50% of field-caught males and females. The nutritive
potential of plant tissues was demonstrated by the 33-d median survival
of P. papatasi series that had been maintained on fresh C. spinosa
branches and water.
REQUEST: [ sand fly ]
(6 articles match this request. 4 articles matching other requests removed)
PMID: 15535608
TITLE: Patterns of exochorion ornaments on eggs of seven South American species
of Lutzomyia sand flies (Diptera: Psychodidae).
AUTHORS: Danielle Nogueira De Almeida, Oliveira Rodrigo Da Silva, Beatriz Gomes
Brazil, Maurilio José Soares
AFFILIATION: Laboratório de Biologia Celular de Microrganismos, Departamento de
Ultra-estrutura e Biologia Celular, Instituto Oswaldo Cruz/FIOCRUZ, Av. Brasil
4365, Manguinhos, 21045-900 Rio de Janeiro, Brasil.
REFERENCE: J Med Entomol 2004 Sep 41(5):819-25
The patterns of exochorion ornaments on eggs of seven South American
Lutzomyia sand fly species were analyzed by scanning electron microscopy
(SEM): Lutzomyia (Lutzomyia) cruzi (Mangabeira 1938), Lutzomyia (
Micropygomyia) evandroi (Costa Lima and Antunes 1936), L. (Nyssomyia)
intermedia (Lutz and Neiva 1912), L. longipalpis (Lutz and Neiva 1912),
L. migonei (Franca 1920), L. (Nyssomyia) neivai (Pinto 1926), and L.
renei (Martins, Falcao, and Silva 1957). Different patterns were
observed, which showed the distinction between some species. Egg
ornaments in L. cruzi and L. longipalpis appear as single, parallel,
unconnected ridges, whereas eggs of L. migonei appear as single,
parallel, connected ridges. Eggs of L. (Nyssomyia) intermedia and L. (N
.) neivai present a new variation of the single, unconnected, parallel
ridges pattern: small tubercles are present, distributed between the
ridges. Eggs of L. renei present an elliptical pattern, with most
structures connected by straight ridges. Eggs of L. (M.) evandroi
present a polygonal pattern, with alternate rows of small and large
hexagons. Our data emphasize the advantages of the SEM approach in the
study of the exochorion patterns of Lutzomyia eggs and in the
distinction of the sand fly species.
PMID: 15535610
TITLE: Taxonomy and distribution of the series pia of the Lutzomyia verrucarum
group (Diptera: Psychodidae), with a description of Lutzomyia emberai n. sp.
AUTHORS: Eduar ElÃas Bejarano, Patricia Duque, Iván DarÃo Vélez
AFFILIATION: Programa de Estudio y Control de Enfermedades Tropicales,
Universidad de Antioquia, Cra. 53 No. 61-30, Apartado Aéreo 1226, MedellÃn,
Colombia.
REFERENCE: J Med Entomol 2004 Sep 41(5):833-41
A new species of phlebotomine sand fly, Lutzomyia emberai n. sp, is
described and illustrated from specimens collected in a dwelling of the
Emberá Indian community, situated in the foothills of the SerranÃa del
Baudól on the Colombian Pacific coast. The morphological
characteristics of L. emberai n. sp. suggest that it belongs to the
series pia of the group verrucarum, easily differentiated from the other
members of this group by diagnostic characters on the palps, labro-
pharynx, thorax, and spermathecal ducts. The discovery of this new
phlebotomine raises to seven the number of species in the series pia,
including Lutzomyia pia (Fairchild & Hertig, 1961); Lutzomyia
reclusa Fernandez & Rogers, 1991; Lutzomyia suapiensis Le Pont,
Torrez-Espejo & Dujardin, 1997; Lutzomyia tihuiliensis Le Pont,
Torrez-Espejo & Dujardin, 1997; Lutzomyia tocaniensis Le Pont,
Torrez-Espejo & Dujardin, 1997; Lutzomyia limafalcaoae (Wolff &
Galati, 2002); and Lutzomyia emberai Bejarano, Duque & Velez, 2004,
n. sp. The taxonomy, distribution, and medical importance of this series
are reviewed.
REQUEST: [ sandfly ]
(1 article matches this request. 1 article matching other requests removed)
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