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1.
Parasitol Int ; 84: 102404, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34129934

RESUMO

Cameline filarosis is an important parasitic disease having an economic impact on the camel industry around the world. However, there has been no study on filarosis in Bactrian camels of Mongolia. Therefore, the aim of the present study was to detect and identify microfilariae of Deraiophoronema evansi (D. evansi) in Bactrian camels from three provinces, located in southern and southwestern Mongolia. Blood samples were obtained from 400 healthy two-humped camels of different ages and both sexes. All blood samples were analysed using a variety of diagnostic techniques. Microfilariae were detected in 30 Bactrian camels (7.5%) by the Knott technique, while 13 Bactrian camels (3.3%) tested positive in a direct smear test. D. evansi was detected in 18 Bactrian camels (4.5%) by PCR assay. Prevalence was shown to be high among Bactrian camels in the age group up to 5 years, while the lowest positive results were obtained for Bactrian camels in the 5-10-year age group and the over 10-year age group. To confirm the morphological identification, D. evansi-COI gene sequences were subjected to phylogenetic analyses. The D. evansi-COI gene sequences from Mongolian two-humped camels were identical to sequences from Iranian one-humped camels and were clustered together with these sequences in the phylogeny. This is the first report of molecular detection and identification of microfilariae of D. evansi in Bactrian camels of Mongolia.


Assuntos
Camelus , Infecções por Dipetalonema/veterinária , Dipetalonema/isolamento & purificação , Animais , Dipetalonema/genética , Infecções por Dipetalonema/diagnóstico , Infecções por Dipetalonema/epidemiologia , Infecções por Dipetalonema/parasitologia , Complexo IV da Cadeia de Transporte de Elétrons/análise , Feminino , Proteínas de Helminto/análise , Masculino , Microfilárias/isolamento & purificação , Mongólia/epidemiologia , Prevalência
2.
Parasitology ; 148(11): 1353-1359, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34100346

RESUMO

Six Dipetalonema species have been reported from Neotropical monkeys, Dipetalonema gracile, Dipetalonema graciliformis and Dipetalonema caudispina being the dominant species found in French Guiana primates. Adult filarioids isolated from the abdominal cavity of tamarins (Saguinus midas) in French Guiana were morphologically and molecularly identified as D. graciliformis. Phylogenetic analysis based on DNA and amino acid sequences of the cox1 gene as well as the concatenated sequences of the cox1 and the 18S genes indicated that D. graciliformis belongs to the clade 4 (ONC4) of Onchocercidae. Blast analysis of the 18S rDNA revealed that D. graciliformis in the studied tamarins is conspecific with the filarioid circulating in howler monkeys (Alouatta macconnelli) in French Guiana, previously referred to as unidentified Onchocercidae species.


Assuntos
Infecções por Dipetalonema/veterinária , Dipetalonema/classificação , Doenças dos Macacos/parasitologia , Saguinus/parasitologia , Animais , Dipetalonema/anatomia & histologia , Dipetalonema/isolamento & purificação , Infecções por Dipetalonema/epidemiologia , Infecções por Dipetalonema/parasitologia , Feminino , Guiana Francesa/epidemiologia , Masculino , Doenças dos Macacos/epidemiologia
3.
J Helminthol ; 93(3): 375-378, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29606157

RESUMO

Dipetalonema caudispina (Molin, 1858) and D. gracile (Rudolphi, 1809) (Filarioidea: Onchocercidae) are two of six known species of filarial nematodes that parasitize Neotropical non-human primates. Adult filariae were collected from the thoracic and abdominal cavities of 38 of 44 specimens of Sapajus macrocephalus (Spix, 1823) and nine of ten specimens of Cebus albifrons (Humboldt, 1812) (Primates: Cebidae), distributed in the Yavarí-Mirín river basin and used locally for human consumption. Co-occurrence of D. caudispina and D. gracile is reported for the first time, with a prevalence of 18.5% (10 of 54 hosts examined). Our finding of D. caudispina and D. gracile in cebids from the Peruvian Amazon constitutes a new geographical record for both filariae, two new host records for D. caudispina, and the first report of D. gracile in S. macrocephalus. In addition, we provide morphometric data for D. caudispina, complementing the original description, as well as scanning electron microscopy details on the structure of the area rugosa and number of caudal papillae in males.


Assuntos
Cebinae/parasitologia , Coinfecção/veterinária , Infecções por Dipetalonema/veterinária , Dipetalonema/classificação , Dipetalonema/isolamento & purificação , Doenças dos Macacos/parasitologia , Cavidade Abdominal/parasitologia , Animais , Biometria , Coinfecção/epidemiologia , Coinfecção/parasitologia , Dipetalonema/anatomia & histologia , Infecções por Dipetalonema/epidemiologia , Infecções por Dipetalonema/parasitologia , Microscopia Eletrônica de Varredura , Doenças dos Macacos/epidemiologia , Peru/epidemiologia , Prevalência , Cavidade Torácica/parasitologia , Topografia Médica
4.
J Helminthol ; 94: e1, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30326978

RESUMO

Dipetalonema gracile is a common parasite in squirrel monkeys (Saimiri sciureus), which can cause malnutrition and progressive wasting of the host, and lead to death in the case of massive infection. This study aimed to identify a suspected D. gracile worm from a dead squirrel monkey by means of molecular biology, and to amplify its complete mitochondrial genome by polymerase chain reaction (PCR) and sequence analysis. The results identified the worm as D. gracile, and the full length of its complete mitochondrial genome was 13,584 bp, which contained 22 tRNA genes, 12 protein-coding genes, two rRNA genes, one AT-rich region and one small non-coding region. The nucleotide composition included A (16.89%), G (20.19%), T (56.22%) and C (6.70%), among which A + T = 73.11%. The 12 protein-coding genes used TTG and ATT as start codons, and TAG and TAA as stop codons. Among the 22 tRNA genes, only trnS1AGN and trnS2UCN exhibited the TΨC-loop structure, while the other 20 tRNAs showed the TV-loop structure. The rrnL (986 bp) and rrnS (685 bp) genes were single-stranded and conserved in secondary structure. This study has enriched the mitochondrial gene database of Dipetalonema and laid a scientific basis for further study on classification, and genetic and evolutionary relationships of Dipetalonema nematodes.


Assuntos
Infecções por Dipetalonema/veterinária , Dipetalonema/genética , Genoma Mitocondrial , Doenças dos Macacos/parasitologia , Saimiri/parasitologia , Animais , Composição de Bases , Sequência de Bases , China , Dipetalonema/classificação , Dipetalonema/isolamento & purificação , Infecções por Dipetalonema/parasitologia , Genoma Helmíntico , Filogenia
5.
Rev. bras. parasitol. vet ; 27(2): 154-160, Apr.-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-959184

RESUMO

Abstract Dipetalonema gracile (Rudolphi, 1809) (Filarioidea: Onchocercidae) is one of six species of cavities filarial parasites of Neotropical non-human primates. The present study recorded the occurrence of D. gracile, provides morphological and morphometric data and extends the geographical distribution. Adult filariae were obtained from the thoracic and abdominal cavities of 38 specimens of woolly monkey, which were used for local human consumption, in the northeastern Peruvian Amazon. Male and female filarids were processed and analysed using light and scanning electron microscopy. Details of the cephalic papillae, post-cloacal bands and papillae, vulva, phasmid position and lateral appendages are showed by scanning electron microscopy and is recorded the occurrencce of Lagothrix poeppigii monkey as a new host of this filaria in the Yavari-Mirin river basin, Peruvian Amazon.


Resumo Dipetalonema gracile (Rudolphi, 1809) (Filarioidea: Onchocercidae), é uma das seis espécies de filarias parasitas de primatas não humanos neotropicais. O presente trabalho registra a ocorrência de D. gracile , proporciona dados morfológicos e morfométricos e amplia sua distribuição geográfica. Filárias adultas foram obtidas da cavidade torácica e abdominal de 38 espécimes de macaco barrigudo, que foram utilizados para consumo humano local. Essa espécie de primatas não humanos neotropicais tem distribuição ao nordeste da Amazônia peruana. Filarídeos machos e fêmeas foram processados e analisados pela microscopia de luz e microscopia eletrônica de varredura. Detalhes das papilas cefálicas, bandas e papilas pós-cloacais, vulva, posição dos fasmídeos e apêndices laterais são mostradas pela microscopia eletrônica de varredura e registra-se a ocorrência do macaco Lagothrix poeppigii como novo hospedeiro desta filaria na bacia do rio Yavari-Mirin na Amazônia peruana.


Assuntos
Animais , Masculino , Feminino , Atelinae/parasitologia , Dipetalonema/isolamento & purificação , Dipetalonema/anatomia & histologia , Peru , Microscopia Eletrônica de Varredura
6.
Rev Bras Parasitol Vet ; 27(2): 154-160, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29846443

RESUMO

Dipetalonema gracile (Rudolphi, 1809) (Filarioidea: Onchocercidae) is one of six species of cavities filarial parasites of Neotropical non-human primates. The present study recorded the occurrence of D. gracile, provides morphological and morphometric data and extends the geographical distribution. Adult filariae were obtained from the thoracic and abdominal cavities of 38 specimens of woolly monkey, which were used for local human consumption, in the northeastern Peruvian Amazon. Male and female filarids were processed and analysed using light and scanning electron microscopy. Details of the cephalic papillae, post-cloacal bands and papillae, vulva, phasmid position and lateral appendages are showed by scanning electron microscopy and is recorded the occurrencce of Lagothrix poeppigii monkey as a new host of this filaria in the Yavari-Mirin river basin, Peruvian Amazon.


Assuntos
Atelinae/parasitologia , Dipetalonema/anatomia & histologia , Dipetalonema/isolamento & purificação , Animais , Feminino , Masculino , Microscopia Eletrônica de Varredura , Peru
7.
Parasitol Res ; 115(4): 1605-10, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26750131

RESUMO

Despite the economic importance of camels, the parasites that affect them have not received adequate attention so far and molecular studies are scarce compared to other livestock. In this study, we characterized peripheral blood microfilariae in 200 healthy one-humped camels (Camelus dromedarius) from south-east Iran by microscopy and molecular tools to receive a more detailed insight into prevalence and species that affect them. Moreover, adult specimens of the filarial nematode Dipetalonema evansi were collected from the carcass of an infected animal. Microscopic examination was performed on Giemsa-stained blood smears, and blood was also spotted on Whatman FTA(®) cards for DNA analysis. Genomic DNA was extracted, and PCR was carried out for the detection of filaroid helminths, followed by sequence analysis of positive samples. Four samples were positive for microfilariae by microscopy, while 16 animals (8 %) were positive by PCR. Sequence analysis revealed D. evansi in all cases. Phylogenetic analysis of a cytochrome C oxidase subunit I (COI) sequence of filaroid nematodes showed that most species in a single genus cluster in the same clade; however, D. evansi and D. gracile are not monophyletic and branch rather at the base of the tree. Further studies on the life cycle of D. evansi, specifically the identification of intermediate host(s), have become feasible with the provision of the first specific COI sequences in this study.


Assuntos
Camelus/parasitologia , Infecções por Dipetalonema/veterinária , Dipetalonema/isolamento & purificação , Animais , Dipetalonema/genética , Infecções por Dipetalonema/epidemiologia , Infecções por Dipetalonema/parasitologia , Geografia , Irã (Geográfico)/epidemiologia , Microfilárias , Filogenia , Prevalência , Sensibilidade e Especificidade , Análise de Sequência de DNA/veterinária
8.
Pak J Biol Sci ; 16(13): 647-50, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24505989

RESUMO

Totally 294 dromedary camels of different ages and both sexes slaughtered at slaughterhouses in Yazd, Isfahan and Kerman provinces were inspected for infection with Dipetalonema evansi. Blood smears of all camels and carcasses of 125 of them (100 from Isfahan and 25 from Yazd) were studied for larva and adult forms of the parasite. Microfilariae were found in peripheral blood smears of 38 out of 294 (12.92%) tested camels, while 20 out of 125 camels (13.89%) harbored D. evansi adult worms in at least one region in their testicle, epididymis, spermatic cord, lung and heart. Two of infected males had adult forms of the parasite in all studied organs simultaneously. Pathological study of infected tissues revealed sections of parasite, severe acute and chronic inflammation, fibrosis and atrophy. D. evansi is endemic and constitutes an important health problem to camels in Iran's central desert, resulting in impaired working capacity and lowered productivity.


Assuntos
Camelus/parasitologia , Infecções por Dipetalonema/veterinária , Dipetalonema/isolamento & purificação , Animais , Infecções por Dipetalonema/epidemiologia , Infecções por Dipetalonema/parasitologia , Infecções por Dipetalonema/patologia , Feminino , Irã (Geográfico)/epidemiologia , Masculino , Prevalência
9.
Indian J Ophthalmol ; 60(3): 228-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22569390

RESUMO

Parasitic infestations of the eye have been reported since centuries, affecting various parts of the eye. Some are subtle, coexisting with vision, while many others damage and destroy, in part or totally, the gift of sight. This report describes a patient with live subconjunctival dipetalonema infestation of the right eye, with 22 parasites removed live in one sitting from one eye.


Assuntos
Túnica Conjuntiva/parasitologia , Doenças da Túnica Conjuntiva/parasitologia , Infecções por Dipetalonema/parasitologia , Dipetalonema/isolamento & purificação , Infecções Oculares Parasitárias/parasitologia , Idoso , Animais , Doenças da Túnica Conjuntiva/diagnóstico , Diagnóstico Diferencial , Infecções por Dipetalonema/diagnóstico , Infecções Oculares Parasitárias/diagnóstico , Humanos , Masculino
10.
Artigo em Inglês | MEDLINE | ID: mdl-22214333

RESUMO

Filarial nematodes are parasites that have the ability to persist in their hosts for extended periods of time due to the employment of various mechanisms to divert or down-regulate the host's immune responses. One of these mechanisms is the production of immunomodulatory excretory-secretory (ES) products. This review will discuss the properties of one such product, ES-62, which over the years, has been shown to interact with and modulate the activities of a variety of cells of the immune system including B and T lymphocytes, dendritic cells, macrophages and mast cells. Overall, ES-62 diverts the immune system towards an anti-inflammatory phenotype and consistent with this it has been shown to have therapeutic potential in models of inflammatory disease associated with autoimmunity and allergy.


Assuntos
Dipetalonema/metabolismo , Proteínas de Helminto/metabolismo , Proteínas de Helminto/farmacologia , Imunomodulação/efeitos dos fármacos , Animais , Dipetalonema/imunologia , Proteínas de Helminto/imunologia , Proteínas de Helminto/toxicidade , Humanos , Fatores Imunológicos/efeitos adversos , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Inflamação/induzido quimicamente , Inflamação/etiologia , Inflamação/imunologia , Glicoproteínas de Membrana/imunologia , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/farmacologia , Glicoproteínas de Membrana/toxicidade , Modelos Biológicos , Fosforilcolina/imunologia
11.
Exp Parasitol ; 132(1): 97-102, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21925176

RESUMO

ES-62 is an immunomodulatory phosphorylcholine (PC)-containing glycoprotein secreted by the rodent filarial nematode Acanthocheilonema viteae. Previously, the use of knockout mice has revealed the effects of ES-62 on macrophages and dendritic cells to be dependent on TLR4. However, it is possible that ES-62 may interact with additional proteins on the surfaces of target cells and hence that cells may vary with respect to receptor usage. In this study, we identified by molecular weight, proteins that interact with ES-62 and found differences amongst the immune system cells studied. Thus, whereas lymphocytes appear to have two major interacting proteins of ∼135 and ∼82 kDa, U937 monocytes only contain an ES-62-binding protein of the latter molecular weight. Binding to the proteins on B cells and U937 cells was blocked by PC, suggesting a critical role for this ES-62 moiety in facilitating interaction. Finally, ES-62 binding is followed by internalization in both macrophages and B cells but only in the former was absence of TLR4 found to block internalization. These findings are consistent with differences in receptor usage by ES-62 amongst different cell-types.


Assuntos
Dipetalonema/metabolismo , Proteínas de Helminto/metabolismo , Receptores de Superfície Celular/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Linfócitos B/metabolismo , Técnicas Biossensoriais , Western Blotting , Membrana Celular/química , Membrana Celular/metabolismo , Dipetalonema/imunologia , Proteínas de Helminto/imunologia , Humanos , Células Jurkat , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Peso Molecular , Monócitos/metabolismo , Receptores de Superfície Celular/química , Linfócitos T/metabolismo , Receptor 4 Toll-Like/química , Células U937
12.
Parasitol Res ; 110(4): 1537-45, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21947342

RESUMO

Canine arthropod-borne infections are of major interest in small animal practice and have been widely investigated in Central and Western Europe. However, only limited epidemiological data are available from South-Eastern European countries, although diseases including babesiosis or dirofilariosis are widely recognised as important canine infections in these countries. A steadily increasing number of dogs imported from South-Eastern Europe into Germany require particular attention by small animal practitioners. In this study, a total of 216 dogs [29 local Romanian pet dogs presented at Salvavet Veterinary Clinic in Bucharest, Romania, and 187 imported stray dogs from Romania (n = 109) and Hungary (n = 78) into Germany] were screened by molecular biological, serological and haematological methods for canine arthropod-borne infections. Eleven different parasitic and bacterial vector-borne pathogens-Babesia canis canis, Babesia canis vogeli, Babesia gibsoni, Babesia felis-like, Hepatozoon canis, Leishmania spp., Dirofilaria immitis, Dirofilaria repens, Acanthocheilonema reconditum, Anaplasma phagocytophilum and Mycoplasma haemocanis-were detected. Fifty-six percent of the dogs were positive by direct methods. B. canis canis was the most prevalent pathogen in dogs imported to Germany (42.8%) and dogs submitted for clinical consultation in Bucharest (44.8%). Our data strongly suggest the introduction of an adjusted screening panel in dogs from South-East Europe in view of increasing importation of dogs into Germany.


Assuntos
Doenças do Cão/epidemiologia , Infecções por Bactérias Gram-Negativas/veterinária , Doenças Parasitárias em Animais/epidemiologia , Anaplasma/isolamento & purificação , Anaplasma/patogenicidade , Animais , Babesia/isolamento & purificação , Babesia/patogenicidade , Dipetalonema/isolamento & purificação , Dipetalonema/patogenicidade , Dirofilaria immitis/isolamento & purificação , Dirofilaria immitis/patogenicidade , Doenças do Cão/diagnóstico , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Feminino , Alemanha/epidemiologia , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Hungria/epidemiologia , Leishmania/isolamento & purificação , Leishmania/patogenicidade , Masculino , Mycoplasma/isolamento & purificação , Mycoplasma/patogenicidade , Doenças Parasitárias em Animais/diagnóstico , Doenças Parasitárias em Animais/parasitologia , Romênia/epidemiologia , Análise de Sequência de DNA
13.
Parasit Vectors ; 4: 143, 2011 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21781294

RESUMO

BACKGROUND: Hippobosca longipennis (the 'dog louse fly') is a blood sucking ectoparasite found on wild carnivores such as cheetahs and lions and domesticated and feral dogs in Africa, the Middle East and Asia, including China. Known as an intermediate host for Acanthocheilonema dracunculoides and a transport host for Cheyletiella yasguri, it has also been suggested that H. longipennis may be a vector for other pathogens, including Acanthocheilonema sp.? nov., which was recently reported to infect up to 48% of dogs in northern India where this species of fly is known to commonly infest dogs. To test this hypothesis, hippoboscid flies feeding on dogs in Ladakh in northern India were collected and subjected to microscopic dissection. RESULTS: A total of 12 infective larvae were found in 10 out of 65 flies dissected; 9 from the head, 2 from the thorax and 1 from the abdomen. The larvae averaged 2, 900 (± 60) µm in length and 34 (± 5) µm in width and possessed morphological features characteristic of the family Onchocercidae. Genetic analysis and comparison of the 18S, ITS-2, 12S and cox-1 genes confirmed the identity of the larvae as the Acanthocheilonema sp.? nov. reported in dogs in Ladakh. CONCLUSION: This study provides evidence for a potential intermediate host-parasite relationship between H. longipennis and the canine Acanthocheilonema sp.? nov. in northern India.


Assuntos
Infecções por Dipetalonema/veterinária , Dipetalonema/isolamento & purificação , Dípteros/parasitologia , Vetores de Doenças , Doenças do Cão/parasitologia , Doenças do Cão/transmissão , Animais , Infecções por Dipetalonema/parasitologia , Infecções por Dipetalonema/transmissão , Cães , Índia , Larva , Microscopia , Parasitologia
14.
J Wildl Dis ; 46(2): 570-3, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20688652

RESUMO

The Mediterranean monk seal (Monachus monachus) is one of the world's most endangered marine mammals. The largest population is located mainly throughout the Aegean and Ionian islands and along the coastline of southern continental Greece. We report the findings of a necropsy and discuss their potential importance to the conservation of the species. The adult female monk seal appeared to be in a good nutritional state. The main necropsy findings were injuries consistent with a violent and sudden death, including three round wounds on the ventral surface of the body and several hematomas, as well as a decomposing male fetus in the uterus. Two nematodes were found in the right ventricle of the heart; no abnormalities were observed in the lungs, pulmonary vessels, or heart. The nematodes were identified as Acanthocheilonema spirocauda. This is the first report of infection of the Mediterranean monk seal with A. spirocauda, even though this is the most common heartworm found in most pinnipeds worldwide. This parasite should be considered in health care monitoring projects of this endangered species.


Assuntos
Infecções por Dipetalonema/veterinária , Dipetalonema/isolamento & purificação , Focas Verdadeiras/parasitologia , Animais , Infecções por Dipetalonema/epidemiologia , Infecções por Dipetalonema/patologia , Infecções por Dipetalonema/transmissão , Espécies em Perigo de Extinção , Evolução Fatal , Feminino , Masculino , Mar Mediterrâneo
15.
Acta Trop ; 116(1): 61-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20525500

RESUMO

Tropomyosins of invertebrates are pan-allergens responsible for wide spread allergic reactions against seafood and arthropods. As invertebrate tropomyosins are highly conserved, helminth tropomyosins are likely to show properties similar to these medically important allergens. Studies with a monoclonal antibody, NR1, raised against tropomyosin of the rodent filarial nematode Acanthocheilonema viteae revealed a B cell epitope common to helminths and marine mollusks, which does not occur in vertebrate tropomyosin. This antibody detected tropomyosin of A. viteae, other filariids, nematodes, trematodes and a cestode, and recognized as well tropomyosin of oyster, squid and octopus, but not of arthropods and vertebrates. Immunohistological analyses of A. viteae, Onchocerca volvulus and other nematodes using NR1 showed that tropomyosin is located in the fibrillar part of the body wall muscles and the uterus, and is also conspicuous in muscles of the pharynx, the vagina and other organs of the nematodes. The abundance of a pan-allergen like tropomyosin in parasitic worms and the counterintuitive, but well documented protection against allergic reactivity by some chronic helminth infections is discussed.


Assuntos
Alérgenos/imunologia , Anticorpos Monoclonais/imunologia , Dipetalonema/imunologia , Invertebrados/imunologia , Tropomiosina/imunologia , Animais , Western Blotting , Países em Desenvolvimento , Dipetalonema/patogenicidade , Infecções por Dipetalonema/imunologia , Infecções por Dipetalonema/patologia , Feminino , Humanos , Hibridomas , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos BALB C
16.
FEBS J ; 276(13): 3454-69, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19456864

RESUMO

Parasitic nematodes can downregulate the immune response of their hosts through the induction of immunoregulatory cytokines such as interleukin-10 (IL-10). To define the underlying mechanisms, we measured in vitro the production of IL-10 in macrophages in response to cystatin from Acanthocheilonema viteae, an immunomodulatory protein of filarial nematodes, and developed mathematical models of IL-10 regulation. IL-10 expression requires stimulation of the mitogen-activated protein kinases extracellular signal-regulated kinase (ERK) and p38, and we propose that a negative feedback mechanism, acting at the signalling level, is responsible for transient IL-10 production that can be followed by a sustained plateau. Specifically, a model with negative feedback on the ERK pathway via secreted IL-10 accounts for the experimental data. Accordingly, the model predicts sustained phospho-p38 dynamics, whereas ERK activation changes from transient to sustained when the concentration of immunomodulatory protein of Acanthocheilonema viteae increases. We show that IL-10 can regulate its own production in an autocrine fashion, and that ERK and p38 control IL-10 amplitude, duration and steady state. We also show that p38 affects ERK via secreted IL-10 (autocrine crosstalk). These findings demonstrate how convergent signalling pathways may differentially control kinetic properties of the IL-10 signal.


Assuntos
Comunicação Autócrina/fisiologia , Dipetalonema , Proteínas de Helminto/imunologia , Interleucina-10/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Macrófagos/imunologia , Modelos Teóricos , Animais , Cistatinas/imunologia , Inibidores de Cisteína Proteinase/metabolismo , Dipetalonema/imunologia , Dipetalonema/patogenicidade , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica , Proteínas de Helminto/genética , Interleucina-10/genética , Macrófagos/citologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fosforilação , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
Parasitol Res ; 104(1): 63-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18762981

RESUMO

The heartworm Acanthocheilonema spirocauda (Leidy, Proc Acad Nat Sci Philadelphia 10:110-112, 1858) Anderson, 1992 is described from material collected from harbour seals in Scandinavia and compared with types and other specimens described by Anderson (Can J Zool 37:481-493, 1959) from harbour seals in eastern USA. Most morphometric characters of the material from USA fall within the ranges established for the Scandinavian one. Some intraspecific variability in the organisation of papillae on the male tail was detected among the Scandinavian specimens. Differences between the specimens from Scandinavia and Eastern USA are also found in the organisation of papillae on the tail of males and females. An excretory pore was not discernible, but a clearly hemizonid-like structure is described. For the first time, scanning electron micrographs present external morphological structures of the species.


Assuntos
Infecções por Dipetalonema/veterinária , Dipetalonema/classificação , Phoca/parasitologia , Animais , Dipetalonema/anatomia & histologia , Dipetalonema/isolamento & purificação , Dipetalonema/ultraestrutura , Infecções por Dipetalonema/parasitologia , Feminino , Coração/parasitologia , Masculino , Microscopia , Microscopia Eletrônica de Varredura , Países Escandinavos e Nórdicos , Especificidade da Espécie
18.
J Parasitol ; 94(5): 1128-38, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18576832

RESUMO

Neotropical primates of the Cebidae and Callitrichidae, in their natural habitats, are frequently infected with a variety of trypanosomes including Trypanosoma cruzi, which causes a serious zoonosis, Chagas' disease. The state of trypanosome infection after a 30-day quarantine period was assessed in 85 squirrel monkeys (Saimiri sciureus) and 15 red-handed tamarins (Saguinus midas), that were wild-caught and exported to Japan as companion animals or laboratory animals, for biomedical research, respectively. In addition to many microfilariae of Mansonella (Tetrapetalonema) mariae at a prevalence of 25.9%, and Dipetalonema caudispina at a prevalence of 3.5%, a few trypomastigotes of Trypanosoma (Megatrypanum) minasense were detected in Giemsa-stained thin films of blood from 20 squirrel monkeys at a prevalence of 23.5%. Although few T. minasense trypomastigotes were found in Giemsa-stained blood films from tamarins, a buffy-coat examination detected trypanosomes in 12 red-handed tamarins (80.0%), and PCR amplification of a highly variable region of the small subunit ribosomal RNA genes (SSU rDNA) for Trypanosoma spp. detected the infection in 14 of the 15 tamarins (93.3%). Nucleotide sequences of the amplicons were identical for trypanosomes from tamarins and squirrel monkeys, indicating a high prevalence but low parasitemia of T. minasense in imported Neotropical nonhuman primates. Based on the SSU rDNA and 5.8S rDNA, the molecular phylogenetic characterization of T. minasense indicated that T. minasense is closely related to trypanosomes with Trypanosoma theileri-like morphology and is distinct from Trypanosoma (Tejeraia) rangeli, as well as from T. cruzi. Using some blood samples from these monkeys, amplification and subsequent sequencing of the glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) gene fragments detected 4 trypanosome genotypes, including 2 types of T. cruzi clade, 1 type of T. rangeli clade, and 1 T. rangeli-related type, but failed to indicate its phylogenetic position based on the gGAPDH gene. Furthermore, species ordinarily classified in the Megatrypanum by morphological criteria do not form a clade in any molecular phylogenetic trees based on rDNA or gGAPDH genes.


Assuntos
Doenças dos Macacos/parasitologia , Saguinus/parasitologia , Saimiri/parasitologia , Trypanosoma/classificação , Tripanossomíase/veterinária , Animais , Sequência de Bases , DNA de Protozoário/química , DNA Ribossômico/química , Dipetalonema/classificação , Dipetalonema/genética , Dipetalonema/isolamento & purificação , Gliceraldeído 3-Fosfato Desidrogenase (NADP+)/genética , Japão/epidemiologia , Mansonella/classificação , Mansonella/genética , Mansonella/isolamento & purificação , Microcorpos/enzimologia , Dados de Sequência Molecular , Doenças dos Macacos/epidemiologia , Conformação de Ácido Nucleico , Filogenia , Reação em Cadeia da Polimerase/veterinária , Prevalência , RNA Ribossômico 5,8S/genética , Trypanosoma/genética , Tripanossomíase/epidemiologia , Tripanossomíase/parasitologia
19.
J Immunol ; 180(6): 4265-72, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18322239

RESUMO

The coincidence between infections with parasitic worms and the reduced prevalence of allergic disease in humans and in animal models has prompted the search for helminth molecules with antiallergic and antiinflammatory potential. We report herein that filarial cystatin, a secreted protease inhibitor of filarial nematodes, suppresses Th2-related inflammation and the ensuing asthmatic disease in a murine model of OVA-induced allergic airway responsiveness. Treatment with recombinant filarial cystatin inhibited eosinophil recruitment, reduced levels of OVA-specific and total IgE, down-regulated IL-4 production, and suppressed allergic airway hyperreactivity when applied during or after sensitization and before challenge with the allergen. Depletion of macrophages by clodronate-containing liposomes prevented the curative effects and restored the levels of infiltrating cells, IgE, and allergic airway reactivity. Blocking of IL-10 by application of anti-IL-10 receptor Abs restored the reduced number of infiltrating cells and the levels of OVA-specific IgE. In contrast, depletion of regulatory T cells by anti-CD25 Abs had only limited effects. Cystatin also modulated macrophage-mediated inflammation in a murine model of dextran sulfate sodium-induced colitis, leading to reduction of inflammatory infiltrations and epithelial damage. Our data demonstrate that treatment with a single helminth protein can exert the antiallergic effects of helminth infections.


Assuntos
Cistatinas/fisiologia , Dipetalonema/imunologia , Fatores Imunológicos/fisiologia , Interleucina-10/biossíntese , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Hipersensibilidade Respiratória/imunologia , Hipersensibilidade Respiratória/prevenção & controle , Doença Aguda , Animais , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/patologia , Hiper-Reatividade Brônquica/prevenção & controle , Colite/imunologia , Colite/prevenção & controle , Cistatinas/uso terapêutico , Feminino , Proteínas de Helminto/uso terapêutico , Mediadores da Inflamação/fisiologia , Interleucina-10/fisiologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Hipersensibilidade Respiratória/patologia
20.
Infect Immun ; 76(1): 221-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17938220

RESUMO

Chitinases of pathogens have been proposed as potential targets of vaccines or specific inhibitors. We studied the genomic organization, transcript levels, developmental expression, and biological function of chitinases in the rodent filarial nematode Acanthocheilonema viteae, a model organism for human-pathogenic filarial worms. Characterization of nine genomic clones from an A. viteae phage library and Southern blot experiments revealed the existence of three different chitinase genes, two of which could theoretically yield functional transcripts. The deduced proteins of these genes had the common modular organization of family 18 chitinases. Northern blot experiments and rapid amplification of cDNA ends-PCR with adult worms and larval stages showed that only one gene is expressed, with high variation in transcript levels, as determined by real-time PCR. Chitinase transcript levels were lowest in the late male stage 4 larva (L4) and peaked in the stage 3 larva (L3), which was corroborated by Western blotting. RNA interference (RNAi) experiments showed that treatment of L3 and adult female worms with double-stranded RNA of chitinase inhibited molting of L3 worms and hatching of microfilariae. RNAi also led to the death of 50% of female worms, revealing the essential role of chitinase in the life cycle of filarial nematodes.


Assuntos
Quitinases/metabolismo , Dipetalonema/enzimologia , Dipetalonema/crescimento & desenvolvimento , Animais , Dipetalonema/genética , Feminino , Regulação da Expressão Gênica , Genes de Helmintos , Genoma Helmíntico , Proteínas de Helminto/genética , Estágios do Ciclo de Vida , Masculino , Dados de Sequência Molecular , Interferência de RNA
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