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1.
Aliehsan Heidari Mehdi Mohebali Kourosh Kabir Hojatallah Barati Yousef Soultani Hossein Keshavarz Behnaz Akhoundi Homa Hajjaran Hosein Reisi 《The Korean journal of parasitology》2015,53(4):379-383
Visceral leishmaniasis (VL) or kala-azar mainly affects children in endemic areas. This study was conducted to determine the seroprevalence of VL using direct agglutination test (DAT) in children living in rural districts of Alborz Province located 30 km from Tehran capital city of Iran. Multi-stage cluster random sampling was applied. Blood samples were randomly collected from 1,007 children under 10 years of age in the clusters. A total of 37 (3.7%) of the studied population showed anti-Leishmania infantum antibodies with titers of ≥1:800. There was a significant association between positive sera and various parts of the rural areas of Alborz Province (P<0.002). Two children with anti-Leishmania infantum antibodies titers of ≥1:3,200 indicated kala-azar clinical features and treated with anti-leishmaniasis drugs in pediatric hospital. The findings of this study indicated that Leishmania infection is prevalent in rural areas of Alborz Province. Therefore, it is necessary to increase the awareness and alertness among physicians and public health managers, particularly in high-risk rural areas of the province in Iran. 相似文献
2.
Dong Ha Bhang Ul Soo Choi Hyun Jeong Kim Kyoung-Oh Cho Sung-Shik Shin Hee-Jeong Youn Cheol-Yong Hwang Hwa-Young Youn 《The Korean journal of parasitology》2013,51(5):545-549
A 12-year-old spayed female mixed-bred dog presented with nasal bleeding of 2 days duration and a skin nodule in the left flank. No abnormalities were found in coagulation profiles and blood pressure. Cytological evaluation of the nodule revealed numerous characteristic round organisms having a nucleus and a bar within macrophages and in the background, consistent with leishmaniasis. In vitro culture was unsuccessful but PCR of the nodular aspirate identified the organisms as Leishmania infantum, and the final diagnosis was canine leishmaniasis. No history of travel to endemic countries was noted. Because the dog had received a blood transfusion 2 years before the illness, serological screening tests were performed in all donor dogs of the commercial blood bank using the commercial Leishmania ELISA test kit, and there were no positive results. Additional 113 dogs with hyperglobulinemia from Seoul were also screened with the same kits but no positive results were obtained. To the best of the author''s knowledge this is the first autochthonous case of canine leishmaniasis in Korea. 相似文献
3.
Kalpalata Tripathy Aparijita Misra Rabinarayn Mallik Debiprasad Misra Niranjan Rout Jayshree Rath 《The Korean journal of parasitology》2010,48(3):245-246
Post kala-azar dermal leishmaniasis (PKDL) is a rare disease. This is a solitary case report from Orissa, India. We describe a case of PKDL in a 55-year-old male who presented with multiple nodular lesions over face, trunk, and extremities. The patient had been to an endemic area of kala-azar and had a previous history of leishmaniasis. Fine needle aspiration cytology samples from skin nodules revealed Leishmania amastigotes. 相似文献
4.
Manal Z. M. Abdellatif Khamis El-Mabrouk Ashraf A. Ewis 《The Korean journal of parasitology》2013,51(1):75-84
Cutaneous leishmaniasis (CL) is an endemic parasitic infection in the Mediterranean region, including Libya and its Al-jabal Al-gharbi province. We aimed at studying the occupational relevance as well as other epidemiological aspects of CL. We investigated 140 CL cases who attended at Gharyan outpatient polyclinic during a period of 6 months in 2009. CL infection was clinically diagnosed and confirmed by demonstration of Leishmania parasites on smears from lesions. Our findings showed that males were more affected than females (P=0.04), and people above 10-years were more affected than younger ones (P=0.0001). A significant percent of CL cases belonged to Al-Kawasem subprovince (P=0.0001). Farm-related activities were the most frequent occupations among CL cases (P=0.04). In addition to farm workers, housewives and students are at risk groups since they are engaged at farm activities. Moreover, those who have occupations that require staying outdoors for a part of night, e.g., policemen, are also at risk. Compared to children, adult CL patients had multiple lesions (P=0.001) that were more prevalent in their upper and lower extremities than the face (P=0.0001). We conclude that CL is a major health problem in Al-jabal Al-gharbi province of Libya. The presence of rodents and sandflies makes it a suitable environment for Leishmania to spread in an endemic epidemiological pattern. Being engaged in farming activities or outdoor occupations increases the risk of infection. Various clinical patterns of CL suggest the presence of more than 1 species of Leishmania at Al-jabal Al-gharbi province. We propose that the 2 species responsible for CL in this area are L. major and L. tropica. Further investigations to identify the leishmanial species responsible for CL at Al-jabal Al-gharbi together with adoption of preventive and control programs are needed. 相似文献
5.
Viscerotropic growth pattern of Leishmania tropica in BALB/c mice is suggestive of a murine model for human viscerotropic leishmaniasis 总被引:1,自引:0,他引:1
Leishmania (L.) tropica is a causative agent of cutaneous leishmaniasis, and occasionally of visceral or viscerotropic leishmaniasis in humans. Murine models of Leishmania infection have been proven to be useful for elucidation of mechanisms for pathogenesis and immunity in leishmaniasis. The aim of this study was to establish a murine model for human viscerotropic leishmaniasis, and the growth pattern of L. tropica was studied in different tissues of BALB/c mice in order to find out whether the parasite visceralizes in this murine model. L. major was used as a control as this species is known to cause a progressive infection in BALB/c mice. L. tropica or L. major was injected into the footpad of mice, and thickness of footpad, parasite loads in different tissues, and the weight of the spleen and lymph node were determined at different intervals. Results showed that L. tropica visceralizes to the spleen and grows there while its growth is controlled in footpad tissues. Dissemination of L. tropica to visceral organs in BALB/c mice was similar to the growth patterns of this parasite in human viscerotropic leishmaniasis. The BALB/c model of L. tropica infection may be considered as a good experimental model for human diseases. 相似文献
6.
James A. Brannigan Zhiyong Yu Michael R. Hodgkinson Helen P. Price Robin J. Leatherbarrow Deborah F. Smith 《Journal of molecular biology》2010,396(4):985-999
N-Myristoyltransferase (NMT) catalyses the attachment of the 14-carbon saturated fatty acid, myristate, to the amino-terminal glycine residue of a subset of eukaryotic proteins that function in multiple cellular processes, including vesicular protein trafficking and signal transduction. In these pathways, N-myristoylation facilitates association of substrate proteins with membranes or the hydrophobic domains of other partner peptides. NMT function is essential for viability in all cell types tested to date, demonstrating that this enzyme has potential as a target for drug development. Here, we provide genetic evidence that NMT is likely to be essential for viability in insect stages of the pathogenic protozoan parasite, Leishmania donovani, causative agent of the tropical infectious disease, visceral leishmaniasis. The open reading frame of L. donovaniNMT has been amplified and used to overproduce active recombinant enzyme in Escherichia coli, as demonstrated by gel mobility shift assays of ligand binding and peptide-myristoylation activity in scintillation proximity assays. The purified protein has been crystallized in complex with the non-hydrolysable substrate analogue S-(2-oxo)pentadecyl-CoA, and its structure was solved by molecular replacement at 1.4 Å resolution. The structure has as its defining feature a 14-stranded twisted β-sheet on which helices are packed so as to form an extended and curved substrate-binding groove running across two protein lobes. The fatty acyl-CoA is largely buried in the N-terminal lobe, its binding leading to the loosening of a flap, which in unliganded NMT structures, occludes the protein substrate binding site in the carboxy-terminal lobe. These studies validate L. donovani NMT as a potential target for development of new therapeutic agents against visceral leishmaniasis. 相似文献
7.
Leishmaniases are tropical and sub-tropical diseases for which classical drugs (i.e. antimonials) exhibit toxicity and drug resistance. Such a situation requires to find new chemical series with antileishmanial activity. This work consists in analyzing the structure of a validated target in Leishmania: the GDP-mannose pyrophosphorylase (GDP-MP), an enzyme involved in glycosylation and essential for amastigote survival. By comparing both human and L. infantum GDP-MP 3D homology models, we identified (i) a common motif of amino acids that binds to the mannose moiety of the substrate and, interestingly, (ii) a motif that is specific to the catalytic site of the parasite enzyme. This motif could then be used to design compounds that specifically inhibit the leishmanial GDP-MP, without any effect on the human homolog. 相似文献
8.
Leishmania infantum cytosolic tryparedoxin (LiTXN1) can be regarded as a potential candidate for drug targeting. This redox active molecule, which belongs to the thioredoxin superfamily, is one constituent of the hydroperoxide elimination cascade in L. infantum and may also be involved in other cellular processes such as DNA synthesis or host-parasite interaction. In order to validate LiTXN1 as a drug target we have employed a gene replacement strategy. We observed that substitution of both chromosomal LiTXN1 alleles was only possible upon parasite complementation with an episomal copy of the gene. Furthermore, contrary to control parasites carrying the empty vector, both the insect and the mammalian stages of L. infantum retained the episomal copy of LiTXN1 in the absence of drug pressure. These results confirm the essentiality of LiTXN1 throughout the life cycle of the parasite, namely in the disease-causing amastigote stage. In addition, the data obtained showed that disruption of one allele of this gene leads only to a 25% reduction in the expression of LiTXN1. Even though this does not affect promastigote growth and susceptibility to hydrogen peroxide, ex vivo infection assays suggest that wild-type levels of LiTXN1 are required for optimal L. infantum virulence. 相似文献
9.
Tunccan OG Tufan A Telli G Akyürek N Pamukçuoğlu M Yılmaz G Hızel K 《The Korean journal of parasitology》2012,50(2):133-136
Visceral leishmaniasis (VL) is a life-threatening infection caused by Leishmania species. In addition to typical clinical findings as fever, hepatosplenomegaly, and cachexia, VL is associated with autoimmune phenomena. To date, VL mimicking or exacerbating various autoimmune diseases have been described, including systemic lupus erythematosus (SLE), rheumatoid arthritis, and autoimmune hepatitis (AIH). Herein, we presented a patient with VL who had overlapping clinical features with SLE, AIH, as well as antimitochondrial antibody (AMA-M2) positive primary biliary cirrhosis. 相似文献
10.
María Soledad Fernández María Soledad Santini Regino Cavia Adolfo Enrique Sandoval Adriana Alicia Pérez Soraya Acardi Oscar Daniel Salomón 《Memórias do Instituto Oswaldo Cruz》2013,108(7):817-824
This study aimed to analyse changes in the spatial distribution of Lutzomyia
longipalpis in Posadas, an urban area located in northeastern Argentina. Data
were obtained during the summer of 2007 and 2009 through two entomological surveys of
peridomiciles distributed around the city. The abundance distribution pattern for 2009 was
computed and compared with the previous pattern obtained in 2007, when the first human
visceral leishmaniasis cases were reported in the city. Vector abundance was also examined
in relation to micro and macrohabitat characteristics. In 2007 and 2009, Lu.
longipalpis was distributed among 41.5% and 31% of the households in the study
area, respectively. In both years, the abundance rates at most of the trapping sites were
below 30 Lu. longipalpis per trap per night; however, for areas
exhibiting 30-60 Lu. longipalpis and more than 60 Lu.
longipalpis, the areas increased in both size and number from 2007-2009.
Lu. longipalpis was more abundant in areas with a higher tree and bush
cover (a macrohabitat characteristic) and in peridomiciles with accumulated unused
material (a microhabitat characteristic). These results will help to prioritise and focus
control efforts by defining which peridomiciles display a potentially high abundance of
Lu. longipalpis. 相似文献
11.
12.
Carla Maia Lídia Dionísio Maria Odete Afonso Luís Neto José Manuel Cristóv?o Lenea Campino 《Memórias do Instituto Oswaldo Cruz》2013,108(4):481-487
The Algarve Region (AR) in southern Portugal, which is an
international tourist destination, has been considered an endemic region of
zoonotic leishmaniasis caused by Leishmania infantum since the
1980s. In the present study, phlebotomine and canine surveys were conducted to
identify sandfly blood meal sources and to update the occurrence of
Leishmania infection in vectors and dogs. Four sandfly
species were captured: Phlebotomus perniciosus,
Phlebotomus ariasi, Phlebotomus sergenti
and Sergentomyia minuta. In one P. perniciosus
female, L. infantum DNA was detected. Blood meal tests showed
that this species had no host preferences and was an opportunistic feeder. An
overall canine leishmaniasis (CanL) seroprevalence of 16.06% was found; the
seroprevalence was 3.88% in dogs housed in kennels and 40.63% in dogs that
attended veterinary clinics. The simultaneous occurrence of dogs and P.
perniciosus infected with L. infantum in the AR
indicates that the region continues to be an endemic area for CanL. Our results
reinforce the need for the systematic spatial distribution of phlebotomine
populations and their Leishmania infection rates and the need
to simultaneously perform pathogen monitoring in both invertebrate and
vertebrate hosts to investigate the transmission, distribution and spreading of
Leishmania infection. 相似文献
13.
Filipe Dantas-Torres Thiago F. Martins Luciana A. Figueredo Sinval P. Brandão-Filho 《Experimental parasitology》2010,125(2):184-185
Phlebotomine sand flies are the only proven biological vectors of Leishmania parasites. However, Rhipicephalus sanguineus ticks have long been suspected to transmit Leishmania infantum in studies carried out in laboratory and natural conditions. In the present study, 5 μl of L. infantum promastigotes (1 × 106 cells per ml) was injected into the hemocel through the coxa I of four engorged females (F1, F2, F3 and F4). Control ticks (F5 and F6) were injected with sterile phosphate-buffered saline (PBS) using the same procedure. Then, these females, their eggs, and the originated larvae were tested by real time polymerase chain reaction (real-time PCR) for the presence of L. infantum kinetoplast DNA (kDNA). Females and eggs were tested after the end of the oviposition period (about 5 weeks post-inoculation) whereas larvae were tested about 4 months after the inoculation of females. All artificially infected females were positive for L. infantum kDNA. In addition, two pools of eggs (one from F2 and other from F4) and four pools of larvae (one from each F1 and F4 and two from F2) were positive for L. infantum kDNA. These results showed, for the first time, the transovarial passage of L. infantum kDNA in R. sanguineus ticks, thus suggesting that the transovarial transmission of L. infantum protozoa in ticks is worth to be investigated. 相似文献
14.
Ravel C Cortes S Pratlong F Morio F Dedet JP Campino L 《International journal for parasitology》2006,36(13):1383-1388
The genus Leishmania includes many pathogenic species which are genetically very distant. The possibility of genetic exchange between different strains is still an important and debated question. Very few genetic hybrids (i.e., offspring of genetically dissimilar species) have been described in Leishmania. In this study, we report the first example of genetic hybrids occurring between two divergent Leishmania species, Leishmania infantum and Leishmania major. These two species have distinct geographical distributions and are transmitted by different vector species to different mammalian reservoir hosts. These hybrid strains were isolated in Portugal from immunocompromised patients and characterized by molecular and isoenzymatic techniques. These approaches showed that these chimeric strains probably contained the complete genome of both L. major and L. infantum. We believe this is the first report of genetic hybrids between such phylogenetically and epidemiologically distant species of Leishmania. This raises questions about the frequency of such cross-species genetic exchange in natural conditions, modalities of hybrid transmission, their long term maintenance as well as the consequences of these transfers on phenotypes such as drug resistance or pathogenicity. 相似文献
15.
Bimal S Singh SK Sinha S Pandey K Sinha PK Ranjan A Bhattacharya SK Das P 《Experimental parasitology》2008,118(2):238-246
In this study, we investigated whether alteration in the CD2 mediated coordination of an immune response was associated with down regulation of CD4 associated Th1 cell response during Visceral Leishmaniasis (VL). Leishmania donovani (Ld) infection in VL patients markedly reduced expression of CD2 cell surface antigen on CD4+ cells. T-cells of VL patients were mostly in G0/G1 stage of the cell cycle (98.20%) with little or no activity of protein kinase C-alpha (PKC-alpha) isoform. However, pre-incubation with activating anti-CD2 monoclonal antibody (MAb) resulted in a corresponding increase up to 2.52-fold in T-cells of G2/M population supported by both activity and expression of PKC-alpha isoform. Furthermore, we observed that co-incubation of T-cell with anti-CD2 increased the lymphocyte-blast population in patients in whom the CD4 cells became more antigen responsive (CD4+ CD69+ cells). Consistent with these observations, it was shown that 59.3% of CD4 cells from patients responded to Ld by producing IFN-gamma. Even in the culture condition, when the T-cells from patients were depleted of APC, IFN-gamma production was noticed after CD2 activation. On the other hand, IL-4 production became low in the anti-CD2 antibody supplemented peripheral blood mononuclear cells (PBMNCs) culture. These findings imply that infection with L. donovani induces less CD2 on the surface of CD4+ T-cells, which once activated orchestrate the protective IFN-gamma dominant host defense mechanism via PKC-mediated signal transduction and cell cycle. 相似文献
16.
Rhajaoui M Sebti F Fellah H Alam MZ Nasereddin A Abbasi I Schönian G 《Parasite (Paris, France)》2012,19(1):81-84
Cutaneous leishmaniasis (CL) in Morocco is caused by three species, Leishmania major, L. tropica and L. infantum. CL has been known in Chichaoua province since 2000. Using DNA extracted from microscopic slides and parasite cultures, collected in the years 2006 and 2009, we identified for the first time L. tropica as the causative agent of CL in this region. Species identification was achieved by performing the ITS1-PCR-RFLP approach. By using this method it was possible to identify parasites in Giemsa stained slides containing less than five parasites per oil-immersion field even they were conserved for up to four months. 相似文献
17.
Veruska Nogueira de Brito Arleana do Bom Parto Ferreira de Almeida Luciano Nakazato Rosemere Duarte Cladson de Oliveira Souza Valéria Régia Franco Sousa 《Memórias do Instituto Oswaldo Cruz》2014,109(7):899-904
Visceral leishmaniasis (VL) in Brazil is transmitted by the phlebotomine
Lutzomyia longipalpis and in some midwestern regions by
Lutzomyia cruzi. Studies of the phlebotomine fauna, feeding
habits and natural infection rate by Leishmania contribute to
increased understanding of the epidemiological chain of leishmaniases and their
vectorial capacity. Collections were performed in Jaciara, state of Mato Grosso from
2010-2013, during which time 2,011 phlebotomines (23 species) were captured (68.70%
Lu. cruzi and 20.52% Lutzomyia whitmani).
Lu. cruzi females were identified by observing the shapes of the
cibarium (a portion of the mouthpart) and spermatheca, from which samples were
obtained for polymerase chain reaction to determine the rates of natural infection.
Engorged phlebotomines were assessed to identify the blood-meal host by ELISA. A
moderate correlation was discovered between the number of Lu. cruzi
and the temperature and the minimum rate of infection was 6.10%. Twenty-two females
were reactive to the antisera of bird (28%), dog (3.30%) and skunk (1.60%). We
conclude that Lu. cruzi and Lu. whitmani have
adapted to the urban environment in this region and that Lu. cruzi
is the most likely vector of VL in Jaciara. Moreover, maintenance of
Leishmania in the environment is likely aided by the presence of
birds and domestic and synanthropic animals. 相似文献
18.
19.
Mohammad A. Oshaghi Naseh Maleki Ravasan Ezat-Aldin Javadian Mohammad M. Sedaghat Homa Hajjaran 《Experimental parasitology》2009,122(1):61-1364
Discrimination of Leishmaniainfantum and L. donovani, the members of the L. (L.) donovani complex, is important for diagnosis and epidemiological studies of visceral leishmaniasis (VL). We have developed two molecular tools including a restriction fragment length polymorphisms of amplified DNA (PCR-RFLP) and a PCR that are capable to discriminate L. donovani from L. infantum. Typing of the complex was performed by a simple PCR of cysteineproteaseB (cpb) gene followed by digestion with DraIII. The enzyme cuts the 741-bp amplicon of L. donovani into 400 and 341 bp fragments whereas the 702 bp of L. infantum remains intact. The designed PCR species-specific primer pair is specific for L. donovani and is capable of amplifying a 317 bp of 3’ end of cpb gene of L. donovani whereas it does not generate an amplicon for L. infantum. The species-specific primers and the restriction enzyme were designed based on a 39 bp insertion/deletion (indel) in the middle of the cpb gene. Both assays could differentiate correctly the two species and are reliable and high-throughput alternatives for molecular diagnosis and epidemiological studies of VL in various foci. 相似文献
20.
Mohammad A. Oshaghi Mohammad Rasolian Fatemeh Mohtarami 《Experimental parasitology》2010,126(4):445-450
Shiraz district in south of Iran is a classical focus of Cutaneous leishmaniasis (CL) and previous research has consistently documented the etiologic agent to be Leishmania tropica and Leishmania major in urban and rural areas, respectively. However, none of the Phlebotomus sergenti, a known vector for L. tropica, of the region has been found infected. We report the first isolation of L. tropica from sandflies in urban community of southern part of Shiraz city. Parasite polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) and gene sequencing analyses indicate CL cases in this community were caused by either L. major or L. tropica. Sandflies of P. sergenti were infrequent, however, three out of 10 (30.0%) females captured in urban area were found infected with L. tropica. But, no human cases were found to be infected with L. tropica. Phlebotomus papatasi were found the most dominant and infected species where 41 out of 207 (20%) tested individuals harboring L. major in suburb area of the city. Patients have been lived in the suburb area of the city where people keep normally domestic animals in their houses which provide appropriate environment for completion of sandfly life cycle and expansion of CL disease in the region. 相似文献