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1.
Parasitology ; 150(14): 1296-1306, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37655743

RESUMO

The distribution of avian haemosporidians of the genus Leucocytozoon in the Neotropics remains poorly understood. Recent studies confirmed their presence in the region using molecular techniques alone, but evidence for gametocytes and data on putative competent hosts for Leucocytozoon are still lacking outside highland areas. We combined morphological and molecular data to characterize a new Leucocytozoon species infecting a non-migratory red-legged seriema (Cariama cristata), the first report of a competent host for Leucocytozoon in Brazil. Leucocytozoon cariamae n. sp. is distinguished from the Leucocytozoon fringillinarum group by its microgametocytes that are not strongly appressed to the host cell nucleus. The bird studied was coinfected with Haemoproteus pulcher, and we present a Bayesian phylogenetic analysis based on nearly complete mitochondrial genomes of these 2 parasites. Leucocytozoon cariamae n. sp. morphology is consistent with our phylogenetic analysis indicating that it does not share a recent common ancestor with the L. fringillinarum group. Haemoproteus pulcher and Haemoproteus catharti form a monophyletic group with Haemocystidium parasites of Reptilia, supporting the polyphyly of the genus Haemoproteus. We also discussed the hypothesis that H. pulcher and H. catharti may be avian Haemocystidium, highlighting the need to study non-passerine parasites to untangle the systematics of Haemosporida.


Assuntos
Doenças das Aves , Coinfecção , Genoma Mitocondrial , Haemosporida , Parasitos , Infecções Protozoárias em Animais , Animais , Filogenia , Brasil/epidemiologia , Teorema de Bayes , Infecções Protozoárias em Animais/parasitologia , Doenças das Aves/parasitologia , Haemosporida/genética , Parasitos/genética , Aves
2.
Vet Parasitol Reg Stud Reports ; 23: 100529, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33678383

RESUMO

A 4-year-old, female common Eider (Somateria mollissima) was presented for mild lethargy with no previous medical history. Numerous intraerythrocytic, round-shaped inclusions were visualized on blood smears, later morphologically identified as Plasmodium relictum parasites. Despite oral doxycycline treatment, clinical condition declined 48 h later. Supportive care was initiated, but the bird died rapidly. Necropsy revealed acute, internal hemorrhages (lungs, air sacs) and subcutaneous, diffuse cervical hematoma, associated with resuscitation attempts. Marked, multicentric amyloidosis (kidney, liver, spleen) was the main histological finding. Molecular analysis identified lineage pGRW11 of P. relictum. This is the first reported case of P. relictum lineage pGRW11 infection in a common Eider. This report describes the clinical features, diagnosis, treatment and associated pathological findings of infection by P. relictum lineage pGRW11 in a common Eider.


Assuntos
Patos/parasitologia , Malária , Plasmodium , Animais , Europa (Continente) , Feminino , Malária/diagnóstico , Malária/tratamento farmacológico , Malária/veterinária , Plasmodium/genética
3.
Parasitol Res ; 119(9): 2975-2981, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32683557

RESUMO

Haemosporidia infections may cause major damage to avian populations and represent a concern for veterinarians working in zoological parks or wildlife rescue centres. Following the fatal infection of 9 Great grey owls (Strix nebulosa) at Mulhouse zoological park, between summer 2013 and 2015, a prospective epidemiological investigation was performed in captive strigiform birds in France in 2016. The purpose was to evaluate the prevalence of haemosporidian parasites in captive Strigiformes and to estimate the infection dynamics around the nesting period. Blood samples were taken from 122 strigiform birds representing 14 species from 15 French zoological parks. Parasites were detected by direct examination of blood smears and by PCR targeting the mitochondrial cytochrome b gene. Haemosporidian parasites were detected in 59 birds from 11 zoos. Three distinct Haemoproteus mitochondrial cytochrome b sequences (haplotypes A and C for H. syrnii and haplotype B for Haemoproteus sp.) as well as two species of Plasmodium were detected. The overall prevalence of Haemoproteus infection was 12.8%. The percentage of birds infected by Haemoproteus varied according to the period of sampling. Nesting season seemed to be at greater risk with an average prevalence of 53.9% compared with winter season with an average prevalence of 14.8%, related to the abundance of the vectors. The prevalence of Plasmodium infection in Strigiformes did not exceed 8% throughout the year. This study confirmed how significant Haemosporidia infection could be in Strigiformes from zoological parks in France. The nesting season was identified as a period of higher risk of infection and consequently the appropriate period to apply prophylactic measures.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Estrigiformes/parasitologia , Animais , Doenças das Aves/sangue , Doenças das Aves/epidemiologia , Citocromos b/genética , França/epidemiologia , Haemosporida/classificação , Haemosporida/genética , Haplótipos , Filogenia , Estudos Prospectivos , Infecções Protozoárias em Animais/sangue , Infecções Protozoárias em Animais/epidemiologia , Proteínas de Protozoários/genética
4.
Parasite ; 26: 21, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30957740

RESUMO

Avian trichomonosis is a common and widespread disease, traditionally affecting columbids and raptors, and recently emerging among finch populations mainly in Europe. Across Europe, finch trichomonosis is caused by a single clonal strain of Trichomonas gallinae and negatively impacts finch populations. Here, we report an outbreak of finch trichomonosis in the wintering populations of Chloris chloris (European greenfinch) and Carduelis carduelis (European goldfinch) from the Boulonnais, in northern France. The outbreak was detected and monitored by bird ringers during their wintering bird ringing protocols. A total of 105 records from 12 sites were collected during the first quarter of 2017, with 46 and 59 concerning dead and diseased birds, respectively. Fourteen carcasses from two locations were necropsied and screened for multiple pathogens; the only causative agent identified was T. gallinae. Genetic characterization was performed by four markers (small subunit ribosomal RNA, hydrogenosomal iron-hydrogenase, and RNA polymerase II subunit 1 genes, and the internal transcribed spacers (ITS) region) and confirmed the T. gallinae strain to be A1, which affects the finch populations of Europe. This was also confirmed by an ITS-based phylogenetic analysis which further illustrated the diversity of the Trichomonas infecting birds. Preliminary data on the survival and dispersion of infected birds were obtained from ring-returns of diseased individuals. The anthropogenic spread of diseases through bird feeding practices is highlighted and some suggestions to prevent pathogen transmission via backyard supplementary feeders for garden birds are given.


Assuntos
Doenças das Aves/epidemiologia , Doenças Transmissíveis Emergentes/veterinária , Surtos de Doenças , Tentilhões/parasitologia , Tricomoníase/veterinária , Migração Animal , Animais , Doenças das Aves/parasitologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/parasitologia , DNA de Protozoário/genética , Europa (Continente) , França/epidemiologia , Filogenia , Estações do Ano , Trichomonas/genética , Trichomonas/isolamento & purificação , Tricomoníase/epidemiologia
5.
Parasitol Res ; 117(12): 3917-3925, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30324256

RESUMO

Here, we report new insights on the erythrocytic murine parasite Anthemosoma garnhami, which was first described from Ethiopia in 1969. Its classification has been debated for years, as this parasite presents some intermediate characters between the Haemosporidia and the Piroplasmida. Based on electron-microscopy, immunological, biochemical and drug sensitivity studies, it was finally assigned to the piroplasms, in the family Anthemosomatidae. In 1985, Anthemosoma sp. was reported from Namibia, and since then, no investigation has involved this parasite. We re-examined the original material, illustrate the blood stages with a set of coloured microphotographs and performed a morphometric analysis. As no type material was designated at the time of the original description, we designate syntypes. This study provides also the first molecular data on A. garnhami with the amplification and sequencing of two genes: the nuclear 18S small subunit ribosomal RNA and the mitochondrial cytochrome c oxydase subunit I. The phylogenetic analyses of both genes confirm that A. garnhami belongs to the Piroplasmida and appears on its own new branch distinct from both Babesids and Theilerids. This result supports the placement of the genus Anthemosoma in its own family but also invalidates the order Anthemosomida. Being paraphyletic with Babesia, the conundrum about the systematics of the piroplasms is discussed as well as the records, the hosts and the possible vectors of Anthemosoma spp.


Assuntos
Piroplasmida/classificação , Piroplasmida/genética , Animais , Babesia/classificação , Ciclo-Oxigenase 1/genética , Etiópia , Camundongos , Namíbia , Filogenia , RNA Ribossômico 18S/genética
6.
Proc Natl Acad Sci U S A ; 113(35): 9834-9, 2016 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-27528689

RESUMO

Haemosporidia parasites have mostly and abundantly been described using mitochondrial genes, and in particular cytochrome b (cytb). Failure to amplify the mitochondrial cytb gene of Nycteria parasites isolated from Nycteridae bats has been recently reported. Bats are hosts to a diverse and profuse array of Haemosporidia parasites that remain largely unstudied. There is a need to obtain more molecular data from chiropteran parasites. Such data would help to better understand the evolutionary history of Haemosporidia, which notably include the Plasmodium parasites, malaria's agents. We use next-generation sequencing to obtain the complete mitochondrial genome of Nycteria parasites from African Nycteris grandis (Nycteridae) and Rhinolophus alcyone (Rhinolophidae) and Asian Megaderma spasma (Megadermatidae). We report four complete mitochondrial genomes, including two rearranged mitochondrial genomes within Haemosporidia. Our results open outlooks into potentially undiscovered Haemosporidian diversity.


Assuntos
Quirópteros/parasitologia , Genoma Mitocondrial , Genoma de Protozoário , Haemosporida/genética , Proteínas Mitocondriais/genética , Proteínas de Protozoários/genética , Animais , Camboja , República Democrática do Congo , Haemosporida/classificação , Sequenciamento de Nucleotídeos em Larga Escala , Mitocôndrias/genética , Filogenia
7.
Parasite ; 22: 31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26551414

RESUMO

Life cycles and molecular data for terrestrial haemogregarines are reviewed in this article. Collection material was re-examined: Hepatozoon argantis Garnham, 1954 in Argas brumpti was reassigned to Hemolivia as Hemolivia argantis (Garnham, 1954) n. comb.; parasite DNA was extracted from a tick crush on smear of an archived slide of Hemolivia stellata in Amblyomma rotondatum, then the 18S ssrRNA gene was amplified by PCR. A systematic revision of the group is proposed, based on biological life cycles and phylogenetic reconstruction. Four types of life cycles, based on parasite vector, vertebrate host and the characteristics of their development, are defined. We propose combining species, based on their biology, into four groups (types I, II, III and IV). The characters of each type are defined and associated with a type genus and a type species. The biological characters of each type are associated with a different genus and a type species. The phylogenetic reconstruction with sequences deposited in the databases and our own new sequence of Hemolivia stellata is consistent with this classification. The classification is as follows: Type I, Hepatozoon Miller, 1908, type species H. perniciosum Miller, 1908; Type II, Karyolysus Labbé, 1894, type species K. lacertae (Danilewsky, 1886) Reichenow, 1913; Type III Hemolivia Petit et al., 1990, type species H. stellata, Petit et al., 1990; and Type IV: Bartazoon n. g., type species B. breinli (Mackerras, 1960).


Assuntos
Coccídios/classificação , Animais , Vetores Aracnídeos/parasitologia , Sequência de Bases , Bancos de Espécimes Biológicos , Coccídios/genética , Coccídios/isolamento & purificação , Contaminação por DNA , DNA de Protozoário , DNA Ribossômico , Especificidade de Hospedeiro , Ixodidae/parasitologia , Estágios do Ciclo de Vida , Filogenia , RNA de Protozoário , RNA Ribossômico 18S , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico , Carrapatos/parasitologia
8.
J Zoo Wildl Med ; 45(3): 577-88, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25314825

RESUMO

A morphologic and molecular epidemiologic investigation was conducted on a captive African black-footed penguin (Spheniscus demersus) colony with a history of Plasmodium infections at La Palmyre Zoo (France). Each penguin received 12.5 mg of pyrimethamine twice a week as a prophylaxis every year from April to November. Although Plasmodium parasites were not detected in blood smears and tissues collected from the penguins, various blood parasites were recorded in blood smears from wild Eurasian magpies (Pica pica) and carrion crows (Corvus corone) sampled at the same time in the study area. These parasites consisted of several Plasmodium spp. (P. lenoblei, P. dorsti, P bioccai, P. relictum, P. dherteae, P. beaucournui, P. maior, P. tranieri, and P. snounoui), Parahaemoproteus spp., Trypanosoma spp., and Leucocytozoon spp. On the other hand, nested polymerase chain reaction enabled detection of Plasmodium DNA in 28/44 (64%) penguins, 15/25 (60%) magpies, and 4/9 (44%) crows. Sequencing and phylogenetic analyses indicated that the parasite DNA amplified from the penguins, magpies, and crows were similar. Magpies and crows could therefore act as a reservoir for penguin Plasmodium infections, which may be more prevalent than previously thought. Morphologic characterization of the Plasmodium spp. detected in the penguins, as well as further biological and epidemiologic studies, are needed to fully understand the transmission of Plasmodium parasites to captive penguins.


Assuntos
Animais de Zoológico , Corvos/sangue , DNA de Protozoário/sangue , Plasmodium/genética , Spheniscidae/sangue , Animais , Animais Selvagens , DNA de Protozoário/genética , Filogenia , Plasmodium/isolamento & purificação
9.
Parasite ; 21: 17, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24759652

RESUMO

Haemoproteus ilanpapernai Karadjian and Landau n. sp. from the Spotted Wood Owl, Strix seloputo, in Singapore is described from material from Ilan Paperna's collection of slides. The species was previously identified as Haemoproteus syrnii (Mayer, 1910). However, comparisons between the material from Strix seloputo and our own material from Strix aluco, the type host of H. syrnii, revealed morphological and molecular differences. H. ilanpapernai n. sp. differs morphologically from H. syrnii by the much smaller size of the gametocytes, the different position of the mature gametocytes in the erythrocyte (apical, subapical, or lateral in H. ilanpapernai vs. always lateral in H. syrnii), the effect on the erythrocyte nucleus (frequently tilted in H. ilanpapernai but not displaced laterally vs. straight and displaced laterally in H. syrnii) and characters of the pigment (aggregated in the gametocytes of H. ilanpapernai vs. dispersed in H. syrnii). A molecular analysis showed that the two species differ by 2.9% at the cyt b and 3.1% at the COI genes.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/isolamento & purificação , Parasitemia/veterinária , Infecções Protozoárias em Animais/parasitologia , Estrigiformes/parasitologia , Animais , Doenças das Aves/epidemiologia , Citocromos b/genética , DNA de Protozoário/genética , Bases de Dados de Ácidos Nucleicos , Complexo IV da Cadeia de Transporte de Elétrons/genética , Eritrócitos/parasitologia , Haemosporida/classificação , Haemosporida/genética , Haemosporida/ultraestrutura , Dados de Sequência Molecular , Parasitemia/epidemiologia , Parasitemia/parasitologia , Infecções Protozoárias em Animais/epidemiologia , Proteínas de Protozoários/genética , Homologia de Sequência do Ácido Nucleico , Singapura/epidemiologia , Especificidade da Espécie
11.
Parasite ; 21: 16, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24717449

RESUMO

Infection with multiple parasite species is clearly the norm rather than the exception, in animals as well as in humans. Filarial nematodes and Plasmodium spp. are important parasites in human public health and they are often co-endemic. Interactions between these parasites are complex. The mechanisms underlying the modulation of both the course of malaria and the outcome of filarial infection are poorly understood. Despite increasing activity in recent years, studies comparing co- and mono-infections are very much in their infancy and results are contradictory at first sight. In this study we performed controlled and simultaneous co-infections of BALB/c mice with Litomosoides sigmodontis filaria and with Plasmodium spp. (Plasmodium yoelii 17 XNL or Plasmodium chabaudi 864VD). An analysis of pathological lesions in the kidneys and lungs and a parasitological study were conducted at different times of infection. Whatever the plasmodial species, the filarial recovery rate was strongly decreased. The peak of parasitaemia in the plasmodial infection was decreased in the course of P. yoelii infection but not in that of P. chabaudi. Regarding pathological lesions, L. sigmodontis can reverse lesions in the kidneys due to the presence of both Plasmodium species but does not modify the course of pulmonary lesions. The filarial infection induces granulomas in the lungs.


Assuntos
Coinfecção/sangue , Filariose/complicações , Filarioidea/isolamento & purificação , Malária/complicações , Carga Parasitária , Parasitemia/parasitologia , Plasmodium chabaudi/isolamento & purificação , Plasmodium yoelii/isolamento & purificação , Animais , Coinfecção/parasitologia , Citocinas/sangue , Feminino , Filariose/sangue , Filariose/parasitologia , Filarioidea/fisiologia , Glomerulonefrite/sangue , Glomerulonefrite/parasitologia , Glomerulonefrite/patologia , Granuloma/parasitologia , Hemeproteínas/análise , Pneumopatias Parasitárias/sangue , Pneumopatias Parasitárias/parasitologia , Pneumopatias Parasitárias/patologia , Macrófagos/química , Malária/sangue , Malária/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Microfilárias/isolamento & purificação , Monócitos/química , Plasmodium chabaudi/fisiologia , Plasmodium yoelii/fisiologia , Cavidade Pleural/parasitologia , Esplenomegalia/parasitologia
12.
Parasite ; 20: 32, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24029169

RESUMO

In France, Haemoproteus syrnii is frequently found in the Tawny Owl, Strix aluco. Additional and complementary features of this species, and in particular the characteristics of volutin, are presented. The authors consider the volutin granules as constant in a given species, and discuss their taxonomic value. These cytoplasmic inclusions appear early during the first stages of development of the gametocytes as an initial granule which multiplies as the parasite develops. They were reported in some species of Haemoproteus but are seldom considered as a specific character and described with precision. Sporogony from ookinete to apparently mature sporozoites appears to take place in a pupiparous hippoboscid (Ornithomyia sp.). One specimen was crushed between two slides and stained with Giemsa. Gametocytes of H. syrnii, many ookinetes, an immature oocyst and mature sporozoites were observed spread all over the smear. This would allow classifying this species in the Haemoproteus subgenus. We provide associated molecular data derived from the cyt b and cox 1 gene from this parasite. We discuss the problems of multiple infections and the difficulties in identifying Haemoproteus species and in deriving conclusions from sequences deposited in databases.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/classificação , Infecções Protozoárias em Animais/parasitologia , Estrigiformes/parasitologia , Animais , Doenças das Aves/epidemiologia , Núcleo Celular/ultraestrutura , Citocromos b/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Eritrócitos/parasitologia , Eritrócitos/ultraestrutura , Feminino , França/epidemiologia , Haemosporida/genética , Haemosporida/fisiologia , Haemosporida/ultraestrutura , Masculino , Dados de Sequência Molecular , Filogenia , Prevalência , Infecções Protozoárias em Animais/epidemiologia , Esporos de Protozoários/fisiologia
13.
BMC Evol Biol ; 11: 299, 2011 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-21992100

RESUMO

BACKGROUND: Timing the origin of human malarias has been a focus of great interest. Previous studies on the mitochondrial genome concluded that Plasmodium in primates, including those parasitic to humans, radiated relatively recently during a process where host switches were common. Those investigations, however, assumed constant rate of evolution and tightly bound (fixed) calibration points based on host fossils or host distribution. We investigate the effect of such assumptions using different molecular dating methods. We include parasites from Lemuroidea since their distribution provides an external validation to time estimates allowing us to disregard scenarios that cannot explain their introduction in Madagascar. RESULTS: We reject the assumption that the Plasmodium mitochondrial genome, as a unit or each gene separately, evolves at a constant rate. Our analyses show that Lemuroidea parasites are a monophyletic group that shares a common ancestor with all Catarrhini malarias except those related to P. falciparum. However, we found no evidence that this group of parasites branched with their hosts early in the evolution of primates. We applied relaxed clock methods and different calibrations points to explore the origin of primate malarias including those found in African apes. We showed that previous studies likely underestimated the origin of malarial parasites in primates. CONCLUSIONS: The use of fossils from the host as absolute calibration and the assumption of a strict clock likely underestimate time when performing molecular dating analyses on malarial parasites. Indeed, by exploring different calibration points, we found that the time for the radiation of primate parasites may have taken place in the Eocene, a time consistent with the radiation of African anthropoids. The radiation of the four human parasite lineages was part of such events. The time frame estimated in this investigation, together with our phylogenetic analyses, made plausible a scenario where gorillas and humans acquired malaria from a Pan lineage.


Assuntos
Lemuridae/parasitologia , Malária/parasitologia , Filogenia , Plasmodium/genética , Animais , Evolução Biológica , Genoma Mitocondrial , Humanos , Madagáscar
14.
Sante ; 21(3): 133-42, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22294247

RESUMO

Chemistry still has a role in the management of malaria, alongside the mosquito netting soaked in insecticide that is used increasingly, as we continue to await the long anticipated vaccine. During its cycle, the hematozoon parasite develops through three major periods. The first, malarial infection, corresponds to the intrahepatic development of infective forms from the mosquito vector; this period is not sensitive to treatment and is often asymptomatic. The period of erythrocytic schizogony is the most urgent, and treatment activity is primordial. Finally, the phase of sexual reproduction, when gametocytes develop within the erythrocytes ensures the perpetuation of the species when these reach the blood-feeding female anopheles mosquitoes. The aim of our work was to study the effect on gametocytes of drugs known to be effective on the asexual blood forms of the protozoan and thus the potential repercussions on malaria transmission. This experimental study was conducted with an animal model whose parasite cycle and modes of transmission are close to those of human malaria: Plasmodium yoelii, maintained on Swiss mice, with the Anopheles stephensi vector (maintained in an animal facility at the National Museum of Natural History in Paris). Two drugs were tested: ferroquine (a chloroquine derivative with a ferrocene molecule at the lateral carbon chain that restores its efficacy against chloroquine-resistant strains) and artesunate (a derivative of artemisinin, from ginghao, a Chinese plant also known as artemisia annua, or sweet wormwood), a treatment of choice in the combined therapies recommended by WHO. The efficacy of these drugs, prescribed at doses subcurative for the asexual forms, were tested against gametocyte production, quantitatively by counting them in the blood and qualitatively by counting the quantity of oocysts developed on the mosquito's midgut, which are indicators of gametocyte activity. The mice that were parasite-infected and then treated served as their own controls: lots of 30 mosquitoes fed on each mouse before treatment and then 90  minutes and 5  hours after treatment. Quantitatively, the comparison of the blood parasite level and the gametocyte index shows that treated mice had a higher level of circulating gametocytes than untreated parasite infested mice, regardless of drug or dose (5 or 10  mg/kg). For artesunate at 5  mg/kg, we noted that the blood gametocyte level was almost double that of the controls. On the other hand, qualitatively, the first results obtained with optical and electronic microscopy showed morphologic alterations of the circulating gametocytes (pigment clumping and lateralisation within red blood cells) and reduced infectivity of the gametocytes for the mosquitoes that fed at 1 and 5  hours after treatment. We were able to demonstrate statistically that the infectivity of gametocytes, measured by the quantity of oocysts counted in the mosquito midgut, was reduced by 70% for those treated with ferroquine and by 85% for those from mice treated by artesunate. Complementary studies will seek to specify the populations (age) of gametocytes damaged by treatment and the importance and nature of their morphologic alterations.


Assuntos
Aminoquinolinas/farmacologia , Antimaláricos/farmacologia , Artemisininas/farmacologia , Compostos Ferrosos/farmacologia , Malária/transmissão , Plasmodium yoelii/efeitos dos fármacos , Animais , Anopheles/parasitologia , Artesunato , Modelos Animais de Doenças , Feminino , Insetos Vetores/parasitologia , Malária/parasitologia , Metalocenos , Camundongos , Testes de Sensibilidade Parasitária , Plasmodium yoelii/crescimento & desenvolvimento
15.
Rev. peru. biol. (Impr.) ; 16(2): 165-168, dic. 2009. ilus
Artigo em Inglês | LIPECS | ID: biblio-1111298

RESUMO

Lankesterella poeppigii n. sp. is described from Bufo poeppigii (Tschudi, 1845) from Peru. Merogony and oogonyoccur in the capillary endothelium and the macrophages in the liver, spleen and kidneys. Meronts are oval, 25,2–29,4 x 15,7–16,8 ìm in size and yield 35–46 merozoites. Oocysts are 26,3–29,4 x 15,1–17,6 ìm in size; sporozoites 9,2-9,8 x 4,2–5,0 ìm in size, assemble in macrophages. Released 8,7–9,8 x 2,8–3,1 ìm sporozoites enter erythrocytes. L. poeppigii is compared with Lankesterella petiti Lainson & Paperna, 1995 infecting Bufomarinus (Linnaeus, 1758) in Brazil. The above mentioned specific characters, added to differences in hosts and geographical location warrant the description of Lankesterella poeppigii from B. poeppigii as a new species.


Lankesterella poeppigii n. sp. es descrita de Bufo poeppigii (Tschudi, 1845) del Perú. La merogonia y oogoniase producen en el endotelio capilar y los macrófagos en el hígado, el bazo y los riñones. Los esquizontes sonovalados, 25,2–29,4 x 15,7–16,8 micras de tamaño y producen 35–46 merozoitos. Los ooquistes miden 26,3–29,4x 15,1–17,6 micras de tamaño; esporozoitos, reunidos en los macrófagos, miden 9,2-9,8 x 4,2-5,0 micras detamaño. Liberados, los esporozoitos miden 8,7–9,8 x 2,8–3,1 micras y entran en los eritrocitos. Lankesterella poeppigii es comparada con L. petiti Lainson y Paperna, 1995, que infecta a Bufo marinus (Linnaeus, 1758) en Brasil. Los caracteres específicos citados, sumados a las diferencias entre los huespédes y en la localización geográfica justifican la clasificación de la Lankesterella de B. poeppigii como una nueva especie.


Assuntos
Apicomplexa , Bufonidae/parasitologia , Peru
17.
Chemistry ; 12(33): 8498-512, 2006 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16927352

RESUMO

The development of the 1,3,5-triazepane-2,6-dione system as a novel, conformationally restricted, and readily accessible class of dipeptidomimetics is reported. The synthesis of the densely functionalized 1,3,5-triazepane-2,6-dione skeleton was achieved in only four steps from a variety of simple linear dipeptide precursors. To extend the practical value of 1,3,5-triazepane-2,6-diones, a general polymer-assisted solution-phase synthesis approach amenable to library production in a multiparallel format was developed. The conformational preferences of the 1,3,5-triazepane-2,6-dione skeleton were investigated in detail by NMR spectroscopy and X-ray diffraction. The ring exhibits a characteristic folded conformation which was compared to that of related dipeptide-derived scaffolds including the more planar 2,5-diketopiperazine (DKP). Molecular and structural diversity was increased further through post-cyclization appending operations at urea nitrogens. Preliminary biological screens of a small collection of 1,3,5-triazepane-2,6-diones revealed inhibitors of the underexplored malaria liver stage and suggest strong potential for this dipeptide-derived scaffold to interfere with and to modulate biological pathways.


Assuntos
Técnicas de Química Combinatória/métodos , Dipeptídeos/química , Compostos Heterocíclicos/síntese química , Mimetismo Molecular , Biblioteca de Peptídeos , Inibidores Enzimáticos/análise , Fígado/parasitologia , Fígado/patologia , Espectroscopia de Ressonância Magnética , Malária/patologia , Conformação Molecular , Projetos Piloto , Difração de Raios X
18.
Am J Ophthalmol ; 140(6): 1002-6, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16376642

RESUMO

PURPOSE: To evaluate the role of pars plana vitrectomy-assisted incisional biopsies in the management of choroidal tumors of unclear origin. DESIGN: Retrospective, noncomparative, consecutive interventional case series. METHODS: Ten consecutive patients with indeterminate choroidal tumors underwent a standardized three-port pars-plana vitrectomy-assisted subretinal biopsy using a bimanual approach with standard intraocular forceps and a diamond knife. Specimens were fixed in formaldehyde embedded in paraffin and further subjected to histopathological and immunohistochemical analyses. RESULTS: A histologic diagnosis was obtained in all (10 of 10) cases including choroidal melanoma (five of 10), metastasis (two of 10), subretinal hemorrhage (two of 10), and nodular scleritis (one of 10). Five eyes were enucleated as a result of the histologic diagnosis. Three cases of postoperative complications were seen in three patients (newly formed rhegmatogenous retinal detachment, increased serous retinal detachment, and vitreous hemorrhage). No cases of intra- or extraocular tumor spread were detected through follow-up periods ranging from 3 to 29 months. CONCLUSIONS: Pars plana vitrectomy-assisted incisional biopsy is a valuable diagnostic procedure for cases of choroidal tumors of unknown origin in selected patients. However, the relatively high frequency of postoperative complications noted in the present study and the potential risk of dissemination of tumor cells underscores the importance of rigorous case selection.


Assuntos
Neoplasias da Coroide/patologia , Melanoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia/efeitos adversos , Biópsia/métodos , Neoplasias da Coroide/secundário , Neoplasias da Coroide/cirurgia , Diagnóstico Diferencial , Enucleação Ocular , Feminino , Humanos , Masculino , Melanoma/secundário , Melanoma/cirurgia , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Hemorragia Retiniana/patologia , Estudos Retrospectivos , Esclerite/patologia , Vitrectomia/métodos
19.
Infect Immun ; 73(8): 4777-86, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16040990

RESUMO

Recent epidemiological observations suggest that clinical evolution of Plasmodium falciparum infections might be influenced by the concurrent presence of another Plasmodium species, and such mixed-species infections are now known to occur frequently in residents of most areas of endemicity. We used mice infected with P. berghei ANKA (PbA), a model for cerebral malaria (CM), to investigate the influence of experimental mixed-species infections on the expression of this pathology. Remarkably, the development of CM was completely inhibited by the simultaneous presence of P. yoelii yoelii but not that of P. vinckei or another line of P. berghei. In the protected coinfected mice, the accumulation of CD8(+) T cells in the brain vasculature, a pivotal step in CM pathogenesis, was found to be abolished. Protection from CM was further found to be associated with species-specific suppression of PbA multiplication. These observations establish the concept of mixed Plasmodium species infections as potential modulators of pathology and open novel avenues to investigate mechanisms implicated in the pathogenesis of malaria.


Assuntos
Malária Cerebral/imunologia , Plasmodium/imunologia , Animais , Sangue/parasitologia , Linfócitos T CD8-Positivos/imunologia , Citometria de Fluxo , Genes Reporter , Malária Cerebral/fisiopatologia , Camundongos , Especificidade da Espécie , Fatores de Tempo
20.
Mol Biochem Parasitol ; 142(2): 184-92, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15913805

RESUMO

During their complex life cycle, malaria parasites adopt morphologically, biochemically and immunologically distinct forms. The intra-hepatic form is the least known, yet of established value in the induction of sterile immunity and as a target for chemoprophylaxis. Using Plasmodium yoelii as a model we present here a novel approach to the elucidation of the transcriptome of this poorly studied stage. Sequences from Plasmodium were obtained in 388 of the 3533 inserts (11%) isolated from liver stages cDNA obtained from optimized cultures with high yields. These corresponded to a total of 88 putative P. yoelii genes. The majority of the transcribed genes identified, code for predicted proteins of as yet unknown function. The RT-PCR analysis carried out for 29 of these genes, confirmed expression at the hepatic stage and provided evidence for complex patterns of genes transcription in the distinct stages found in the mosquito and vertebrate host. The results demonstrate the efficacy of the approach that can now be applied to further detailed analysis of the hepatic stage transcriptome of Plasmodium.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Fígado/parasitologia , Malária/parasitologia , Plasmodium yoelii/crescimento & desenvolvimento , Proteoma , Proteínas de Protozoários/metabolismo , Animais , Células Cultivadas , Biologia Computacional/métodos , Feminino , Perfilação da Expressão Gênica , Hepatócitos/parasitologia , Estágios do Ciclo de Vida , Camundongos , Camundongos Endogâmicos C57BL , Plasmodium yoelii/genética , Plasmodium yoelii/metabolismo , Proteínas de Protozoários/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , RNA de Protozoário/análise , RNA de Protozoário/genética , RNA de Protozoário/isolamento & purificação , Transcrição Gênica
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