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1.
J Parasitol ; 106(5): 611-615, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32997755

RESUMO

Oxyuricassis ekstromi n. sp. is the third species of the genus described from the intestine of Lasiancistrus saetiger Armbruster in Brazil. This species can be easily differentiated from its congeners by the presence of a tooth-like sclerotized piece that occupies half of the stoma and absence of spine projections on the tail of both males and females. Also, males of the new species lack caudal alae present in Oxyuricassis coronatus and Oxyuricassis hexaspinatus. Additionally, we observed a different number and pattern of the distribution of cloacal papilla; males of O. coronatus and O. hexaspinatus have 1 pair of pre-cloacal and 2 pairs of post-cloacal papillae; while the new species has 1 pre-cloacal and 3 post-cloacal pairs of papillae.


Assuntos
Peixes-Gato/parasitologia , Doenças dos Peixes/parasitologia , Enteropatias Parasitárias/veterinária , Oxiuríase/veterinária , Oxyuroidea/classificação , Animais , Brasil , Feminino , Enteropatias Parasitárias/parasitologia , Intestinos/parasitologia , Masculino , Microscopia Eletrônica de Varredura/veterinária , Oxiuríase/parasitologia , Oxyuroidea/anatomia & histologia , Oxyuroidea/ultraestrutura , Rios
2.
Med Vet Entomol ; 32(4): 462-472, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30027674

RESUMO

The flea genus Neotyphloceras Rothschild (Siphonaptera: Ctenophthalmidae) includes five species and two subspecies distributed from Venezuela to southern Chile and Argentina. Only Neotyphloceras crassispina hemisus Jordan has been registered in Bolivia. The present study examines species of Neotyphloceras collected in Bolivian localities in the Departments of La Paz, Cochabamba and Tarija, and describes the morphology of the modified abdominal segments in males and females of Neotyphloceras rosenbergi Rothschild on the basis of type material and specimens collected from Tarija. A new species, Neotyphloceras boliviensis n. sp., is described and new host associations are reported for N. rosenbergi, Neotyphloceras crassispina crassispina and N. crassispina hemisus. Neotyphloceras c. crassispina and N. rosenbergi are reported for the first time in Bolivia. The distribution of N. rosenbergi is extended 1600 km to the south. Given the potential medical and veterinary significance of fleas as disease vectors, and considering that in the Departments of La Paz and Tarija several human cases of plague have been reported, and species of flea have been identified as main vectors of these diseases, the new records of fleas in Bolivia reported herein may be useful for epidemiological studies on flea-borne diseases.


Assuntos
Infestações por Pulgas/veterinária , Gambás/parasitologia , Ratos/parasitologia , Doenças dos Roedores/parasitologia , Sigmodontinae/parasitologia , Sifonápteros/classificação , Animais , Bolívia/epidemiologia , Feminino , Infestações por Pulgas/epidemiologia , Infestações por Pulgas/parasitologia , Masculino , Doenças dos Roedores/epidemiologia , Sifonápteros/anatomia & histologia
3.
Lett Appl Microbiol ; 66(6): 491-495, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29575121

RESUMO

The continued emergence and global spread of bacterial antibiotic resistance has fuelled the search for novel antimicrobial agents and resistance-modifying compounds. Manuka honey has both antimicrobial properties and the ability to increase the efficacy of FDA-approved antibiotic drugs. Compared to other types of honey, manuka honey contains elevated levels of methylglyoxal (MGO), a small molecule that contributes to its antibacterial activity. Manuka honey has shown particular promise for the treatment of antibiotic-resistant Gram-positive organisms such as methicillin-resistant Staphylococcus aureus. Linezolid is an oxazolidinone antibiotic used in the treatment of infections caused by a range of Gram-positive pathogens. Here, we demonstrate that manuka honey, as well as MGO in isolation, increases the sensitivity of S. aureus to linezolid in both agar diffusion and broth microdilution assays. This synergistic interaction is mediated in part by increased intracellular accumulation of linezolid in the presence of MGO. SIGNIFICANCE AND IMPACT OF THE STUDY: Manuka honey is widely recognized for its antimicrobial activity. Our study adds to the growing body of evidence that manuka honey and its active ingredient, methylglyoxal (MGO), can also function as antibiotic adjuvants. In this study, we provide the first report of synergy between MGO and linezolid against Staphylococcus aureus. Both manuka honey and purified MGO significantly increased the sensitivity of S. aureus to linezolid.


Assuntos
Antibacterianos/farmacologia , Mel/análise , Linezolida/farmacologia , Aldeído Pirúvico/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Farmacorresistência Bacteriana , Sinergismo Farmacológico , Humanos , Testes de Sensibilidade Microbiana , Aldeído Pirúvico/análise , Infecções Estafilocócicas/tratamento farmacológico
4.
J Parasitol ; 103(2): 176-182, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27902893

RESUMO

This study presents the helminth composition and parameters of infection by several species of nematodes in teiid lizards, Ameiva ameiva ameiva (Linnaeus, 1758), Cnemidophorus cryptus Cole and Dessauer, 1993, and Kentropyx calcarata Spix, 1825 from the Brazilian Amazonian Rainforest. The population of lizards studied were parasitized by 6 species of Phylum Nemata including: Spinicauda spinicauda (Olfers, 1919), Parapharyngodon alvarengai Freitas, 1957, Physaloptera sp. (adults), Physaloptera sp. (larvae), Piratuba digiticauda Lent and Freitas, 1941, and Anisakidae (larvae). The overall prevalence was 66.17% and the mean intensity of infection was 19.40 ± 25.48. The association between the body-length of lizards and the abundance and richness of parasitic nematodes was statistically significant only in Ameiva a. ameiva. A new host record is reported here with 1 specimen of the family Anasakidae in Ameiva a. ameiva. Both S. spinicauda and Physaloptera sp. represent new records from C. cryptus.


Assuntos
Ascaridoidea/classificação , Lagartos/parasitologia , Infecções por Nematoides/veterinária , Oxyuroidea/classificação , Spiruroidea/classificação , Animais , Brasil/epidemiologia , Feminino , Lagartos/anatomia & histologia , Masculino , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia , Prevalência , Floresta Úmida
5.
J Helminthol ; 91(6): 762-766, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27809941

RESUMO

A unique adaptation of many internal parasites of mammals is their ability to stay in the intestine for extended periods of time and resist the normal peristaltic movements and forces that push and expel material. To better understand parasite adhesion behaviour and replicate their attachment method in medical devices, an experiment was designed and performed using the rat tapeworm, Hymenolepis diminuta. The experiment employed a tensile test machine and a digital scale and was designed to calculate the attachment strength of the scolex to the mucosa through the change of the value of the digital scale during the tensile test. The attachment force of H. diminuta is 0.021 ± 0.011 g. This method could be applied in studies of parasite biomechanics and the results may help medical device researchers to better mimic the unique functional morphology of this species of parasite.


Assuntos
Himenolepíase/veterinária , Hymenolepis diminuta/química , Hymenolepis diminuta/fisiologia , Intestinos/parasitologia , Parasitologia/métodos , Doenças dos Roedores/parasitologia , Animais , Fenômenos Biomecânicos , Himenolepíase/parasitologia , Parasitologia/instrumentação , Ratos
6.
Bone Marrow Transplant ; 51(7): 945-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26950375

RESUMO

Since 1991, three sequential prospective clinical trials have been conducted by the 'Head Start' (HS) Consortium in which young children with newly-diagnosed malignant central nervous system (CNS) tumors were treated with induction chemotherapy followed by single-cycle marrow-ablative chemotherapy and autologous hematopoietic rescue as a means of improving disease cure rate and quality of survival through avoidance (<6 years old at diagnosis) or reduction (6-10 years old) of brain irradiation. Bone Marrow (HS I) or filgrastim-mobilized peripheral hematopoietic cells (HS II and III) were obtained following recovery from the first and/or second induction cycles. Radiotherapy was administered following all chemotherapy only for patients with residual tumor following completion of induction or with age greater than 6 years at diagnosis. Two hundred and twenty-six children were enrolled on three consecutive HS trials with primary malignant CNS tumors and underwent marrow-ablative chemotherapy. The 100-day treatment-related mortality (TRM) steadily declined as did grade IV transplant-related oropharyngeal mucositis. Factors most likely associated with the decrease in TRM and morbidity are increasing experience with the marrow-ablative chemotherapy regimen combined with improved leukapheresis and post-reinfusion supportive care techniques, contributing toward improved overall survival.


Assuntos
Neoplasias do Sistema Nervoso Central/terapia , Ensaios Clínicos como Assunto/normas , Transplante de Células-Tronco Hematopoéticas/métodos , Neoplasias do Sistema Nervoso Central/mortalidade , Neoplasias do Sistema Nervoso Central/radioterapia , Criança , Terapia Combinada , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Transplante de Células-Tronco Hematopoéticas/tendências , Humanos , Quimioterapia de Indução/métodos , Morbidade/tendências , Mortalidade/tendências , Agonistas Mieloablativos/uso terapêutico , Estudos Retrospectivos , Transplante Autólogo
7.
Bone Marrow Transplant ; 51(4): 542-5, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26726947

RESUMO

Recurrence of malignant brain tumors results in a poor prognosis with limited treatment options. High-dose chemotherapy with autologous hematopoietic cell rescue (AHCR) has been used in patients with recurrent malignant brain tumors and has shown improved outcomes compared with standard chemotherapy. Temozolomide is standard therapy for glioblastoma and has also shown activity in patients with medulloblastoma/primitive neuro-ectodermal tumor (PNET), particularly those with recurrent disease. Temozolomide was administered twice daily on days -10 to -6, followed by thiotepa 300 mg/m(2) per day and carboplatin dosed using the Calvert formula or body surface area on days -5 to -3, with AHCR day 0. Twenty-seven patients aged 3-46 years were enrolled. Diagnoses included high-grade glioma (n=12); medulloblastoma/PNET (n=9); central nervous system (CNS) germ cell tumor (n=4); ependymoma (n=1) and spinal cord PNET (n=1). Temozolomide doses ranged from 100 mg/m(2) per day to 400 mg/m(2) per day. There were no toxic deaths. Prolonged survival was noted in several patients including those with recurrent high-grade glioma, medulloblastoma and CNS germ cell tumor. Increased doses of temozolomide are feasible with AHCR. A phase II study using temozolomide, carboplatin and thiotepa with AHCR for children with recurrent malignant brain tumors is being conducted through the Pediatric Blood and Marrow Transplant Consortium.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Transplante de Células-Tronco Hematopoéticas , Adolescente , Adulto , Autoenxertos , Carboplatina/administração & dosagem , Criança , Pré-Escolar , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Taxa de Sobrevida , Temozolomida , Tiotepa/administração & dosagem
8.
J Helminthol ; 89(1): 34-41, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26262594

RESUMO

Plagioscion squamosissimus (Heckel, 1840) (Osteichthyes: Sciaenidae) is considered piscivorous and is a generalist species endemic to the Amazon region. This fish is an important part of the natural ecosystems in which it occurs and provides basic functional components in the food web. The genus Neoechinorhynchus Stiles & Hassall, 1905 is distributed worldwide and parasitizes fish and turtles, but there are few reports of parasites of this genus in South America, due to the high diversity of fish that can be found in this region. A new species of thorny-headed worm (Acanthocephala: Neoechinorhynchidae) is described from P. squamosissimus from Guajará Bay, Belém, Pará, Brazil. In general, the unique characteristics of the hooks on the anterior end of the proboscis and the length-to-width ratio relationship separate this new species from other described species in the genus Neoechinorhynchus. Although the species in this genus are mostly found in North America, the dearth of species known from the neotropics may be due to the lack of studies in this region.


Assuntos
Acantocéfalos/isolamento & purificação , Doenças dos Peixes/parasitologia , Helmintíase Animal/parasitologia , Intestinos/parasitologia , Acantocéfalos/anatomia & histologia , Acantocéfalos/classificação , Acantocéfalos/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Feminino , Masculino , Perciformes/parasitologia
9.
Genes Brain Behav ; 13(5): 478-87, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24679220

RESUMO

Gene regulation resulting from glucocorticoid receptor and glucocorticoid response element interactions is a hallmark feature of stress response signaling. Imbalanced glucocorticoid production and glucocorticoid receptor activity have been linked to socioeconomically crippling neuropsychiatric disorders, and accordingly there is a need to develop in vivo models to help understand disease progression and management. Therefore, we developed the transgenic SR4G zebrafish reporter line with six glucocorticoid response elements used to promote expression of a short half-life green fluorescent protein following glucocorticoid receptor activation. Herein, we document the ability of this reporter line to respond to both chronic and acute exogenous glucocorticoid treatment. The green fluorescent protein expression in response to transgene activation was high in a variety of tissues including the brain, and provided single-cell resolution in the effected regions. The specificity of these responses is demonstrated using the partial agonist mifepristone and mutation of the glucocorticoid receptor. Importantly, the reporter line also modeled the temporal dynamics of endogenous stress response signaling, including the increased production of the glucocorticoid cortisol following hyperosmotic stress and the fluctuations of basal cortisol concentrations with the circadian rhythm. Taken together, these results characterize our newly developed reporter line for elucidating environmental or genetic modifiers of stress response signaling, which may provide insights to the neuronal mechanisms underlying neuropsychiatric disorders such as major depressive disorder.


Assuntos
Receptores de Glucocorticoides/genética , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados/genética , Encéfalo/metabolismo , Encéfalo/fisiologia , Ritmo Circadiano , Hidrocortisona/metabolismo , Mifepristona/farmacologia , Pressão Osmótica , Receptores de Glucocorticoides/antagonistas & inibidores , Receptores de Glucocorticoides/metabolismo , Elementos de Resposta , Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologia , Proteínas de Peixe-Zebra/agonistas , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
10.
Prev Vet Med ; 114(3-4): 174-87, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24655577

RESUMO

The United States (U.S.) response to viral hemorrhagic septicemia virus (VHSV) IVb emergence in the Laurentian Great Lakes (GL) included risk-based surveillance for cost-effective decision support regarding the health of fish populations in open systems. All U.S. VHSV IVb isolations to date derive from free-ranging fish from GL States. Most originate in the region designated by US Geological Survey hydrologic unit code (HUC) 04, with the exception of two detections in neighboring Upper Mississippi (HUC 05) and Ohio (HUC 07) regions. For States outside the GL system, disease probability was assessed using multiple evidence sources. None substantiated VHSV IVb absence using surveillance alone, in part due to the limited temporal relevance of data in open systems. However, Bayesian odds risk-based analysis of surveillance and population context, coupled with exclusions where water temperatures likely preclude viral replication, achieved VHSV IVb freedom assurance for 14 non-GL States by the end of 2012, with partial evidence obtained for another 17 States. The non-GL region (defined as the aggregate of 4-digit HUCs located outside of GL States) met disease freedom targets for 2012 and is projected to maintain this status through 2016 without additional active surveillance. Projections hinge on continued basic biosecurity conditions such as movement restrictions and passive surveillance. Areas with navigable waterway connections to VHSV IVb-affected HUCs (and conducive water temperatures) should receive priority for resources in future surveillance or capacity building efforts. However, 6 years of absence of detections in non-GL States suggests that existing controls limit pathogen spread, and that even spread via natural pathways (e.g., water movement or migratory fish) appears contained to the Great Lakes system. This report exemplifies the cost-effective use of risk-based surveillance in decision support to assess and manage aquatic animal population health in open systems.


Assuntos
Septicemia Hemorrágica Viral/virologia , Novirhabdovirus/classificação , Animais , Doenças Transmissíveis Emergentes , Peixes , Great Lakes Region/epidemiologia , Septicemia Hemorrágica Viral/epidemiologia , Vigilância da População , Fatores de Risco
11.
Eur J Cancer Care (Engl) ; 23(4): 481-92, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24472013

RESUMO

Couplelinks is an original, professionally facilitated online intervention tailored to the unique challenges facing young women with breast cancer and their male partners. The purpose of this evaluation was to determine the feasibility and acceptability of the intervention and areas for improvement. Sixteen couples were sequentially enrolled over an 18-month period. Couples provided feedback via a treatment satisfaction survey, and post-treatment interviews with a sub-group of participants. Qualitative information was analysed for themes relevant to the program's acceptability, perceived benefits and limitations, and directions for improvement. Of the 16 couples who enrolled, six completed four modules or less, and 10 completed the entire program. Completers reported satisfaction with the program overall, as well as with the website useability and professional facilitation. Reported benefits were: enhanced communication and self-other knowledge; creation of opportunities for meaningful, cancer-related discussion; affirmation of relationship strengths; and a greater sense of closeness between partners. The main reported limitation was how program participation disrupted the couple's usual routine. Themes related to non-completion suggest that partners with particularly elevated relational or illness-related distress, or with differential levels of motivation, are less likely to finish. These findings have led to targeted improvements to the website and intervention protocol.


Assuntos
Neoplasias da Mama/psicologia , Características da Família , Internet , Estresse Psicológico/terapia , Adulto , Comunicação , Estudos de Viabilidade , Feminino , Humanos , Relações Interpessoais , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Satisfação do Paciente , Projetos Piloto , Estresse Psicológico/psicologia , Terapia Assistida por Computador
12.
J Wildl Dis ; 46(1): 146-51, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20090027

RESUMO

We investigated the responses of endoparasites in red-backed voles (Myodes gapperi) to fire in a boreal forest ecosystem. Because fire affects the environmental conditions and biodiversity of the forest ecosystem, the life cycle of parasites may also be affected because of the absence of intermediate hosts in the environment. We hypothesized that the prevalence of endoparasites would be influenced by the parasites' life cycle and habitat characteristics (forest vs. burned). We found that prevalence of endoparasites was different between forested and burned habitats (chi(2)=37.49, P<0.001). Cestodes, nematodes, and coccidia showed different responses to habitat alteration (chi(2)=37.43, P<0.001). There was a higher prevalence of cestodes in forested (53.5%) than burned habitats (35.0%). However, there was higher prevalence of coccidia in burned (55.0%) than forested (42.9%) habitats. Furthermore, although prevalence of cestode infection was lower in burned than forested habitat, individuals in both habitats had similar intensities of cestodes. Our study showed that habitat can significantly affect the parasite communities, depending on specific parasite life cycles.


Assuntos
Arvicolinae/parasitologia , Incêndios , Interações Hospedeiro-Parasita , Parasitos/crescimento & desenvolvimento , Doenças dos Roedores/parasitologia , Árvores , Animais , Animais Selvagens , Ecossistema , Estágios do Ciclo de Vida , Parasitos/classificação , Doenças Parasitárias em Animais/epidemiologia , Doenças Parasitárias em Animais/parasitologia
13.
Bone Marrow Transplant ; 41(10): 867-72, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18246113

RESUMO

The aim of this study was to identify risk factors associated with PFS in patients with Ewing sarcoma undergoing ASCT; 116 patients underwent ASCT in 1989-2000 and reported to the Center for International Blood and Marrow Transplant Research. Eighty patients (69%) received ASCT as first-line therapy and 36 (31%), for recurrent disease. Risk factors affecting ASCT were analyzed with use of the Cox regression method. Metastatic disease at diagnosis, recurrence prior to ASCT and performance score <90 were associated with higher rates of disease recurrence/progression. Five-year probabilities of PFS in patients with localized and metastatic disease at diagnosis who received ASCT as first-line therapy were 49% (95% CI 30-69) and 34% (95% CI 22-47) respectively. The 5-year probability of PFS in patients with localized disease at diagnosis, and received ASCT after recurrence was 14% (95% CI 3-30). PFS rates after ASCT are comparable to published rates in patients with similar disease characteristics treated with conventional chemotherapy, surgery and irradiation suggesting a limited role for ASCT in these patients. Therefore, ASCT if considered should be for high-risk patients in the setting of carefully controlled clinical trials.


Assuntos
Agonistas Mieloablativos/uso terapêutico , Sarcoma de Ewing/terapia , Transplante de Células-Tronco/métodos , Adolescente , Adulto , Criança , Terapia Combinada , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Sarcoma de Ewing/mortalidade , Sarcoma de Ewing/secundário , Análise de Sobrevida , Transplante Autólogo
14.
J Parasitol ; 87(3): 656-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11426731

RESUMO

Individuals of a new species of Vexillata were collected from the small intestines of Liomys pictus from the Estaci6n de Biología Chamela, in Jalisco State, Mexico. The new species shows an array of characters that allow us to recognize it as a member of Vexillata; however, it can be distinguished from other species of the genus in that males possess an asymmetrical caudal bursa, females possess a characteristic cuticular inflation at the level of the ovijector, and both sexes possess a synlophe with 9 ridges at the midbody. Additional detail of the synlophe of Vexillata armandae Gardner et al., 1994 from Chaetodipus hispidus in New Mexico shows that both sexes have 12 cuticular ridges just posterior to the cephalic inflation, and in the posterior region of the body, females have 9 ridges of equal size while males possess 11 equal-sized ridges. In both sexes, the carene disappears at the posterior end of the body.


Assuntos
Doenças dos Roedores/parasitologia , Trichostrongyloidea/classificação , Tricostrongiloidíase/veterinária , Animais , Feminino , Masculino , Roedores , Trichostrongyloidea/anatomia & histologia , Tricostrongiloidíase/parasitologia
15.
Syst Parasitol ; 47(3): 223-30, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11071158

RESUMO

A new pinworm parasite is described from Abrocoma cinerea, a caviomorph rodent of the superfamily Octodontoidea from the Andes of Bolivia. The new species, Helminthoxys abrocomae n. sp., possesses special secretory mamelons which we consider a synapomorphy of the genus Helminthoxys. Within Helminthoxys, the closest relatives are found in octodontoid rodents: H. gigantea occurs in Octodon degus in Chile and O. bridgesi in Argentina, and H. freitasi is a parasite of Thrichomys aperoides in Brazil. H. abrocomae n. sp. differs from both other species morphometrically in relation to different parts of the body in both sexes, particularly the size of the body, spicule, gubernaculum and eggs, by the presence of a rough cuticular area around the cephalic sensory papillae and by the possession of very well-developed cervical alae which are strongly curved dorsally. H. abrocomae n. sp. is the tenth nominal species described in Helminthoxys, all of them being parasites of caviomorph rodents.


Assuntos
Oxyurida/classificação , Roedores/parasitologia , Animais , Bolívia , Feminino , Fenômenos Geológicos , Geologia , Masculino , Oxyurida/anatomia & histologia
16.
J Parasitol ; 86(3): 545-54, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10864253

RESUMO

Filarioid nematodes of the genus Litomosoides occur in the abdominal and (or) thoracic cavities of marsupials, rodents, and bats of the Nearctic and Neotropical regions. In this study, the phylogenetic relationships among these nematodes were estimated with a parsimony analysis of morphological characters derived from species descriptions. This nonweighted analysis produced 20 shortest trees. The monophyly of the genus was not supported in that Litomosoides thomomydis and Litomosoides westi failed to group with the other members of the genus. When these 2 taxa (parasites of pocket gophers) were excluded, monophyly of Litomosoides was supported by 2 synapomorphies (structure of the walls and general shape of the stoma); however, ancestor-descendant relationships among the species in the genus were not well resolved. A posteriori reweighting of the characters produced a single tree, different from all 20 most parsimonious trees. Alternative host-parasite evolutionary models were tested against these results supporting the process of host switching as being most important in forming the patterns of mammal-nematode associations that have been detected in this group of nematodes.


Assuntos
Quirópteros/parasitologia , Filariose/veterinária , Filarioidea/classificação , Marsupiais/parasitologia , Filogenia , Roedores/parasitologia , América , Animais , Feminino , Filariose/parasitologia , Filarioidea/anatomia & histologia , Filarioidea/fisiologia , Interações Hospedeiro-Parasita , Masculino
17.
J Parasitol ; 86(1): 89-98, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10701570

RESUMO

Cladistic analysis of a numerical data matrix describing 27 characters for species of Taenia resulted in 4 most parsimonious phylogenetic trees (174 steps; consistency index = 0.28; homoplasy index = 0.72; retention index = 0.48). Monophyly for Taenia is diagnosed by the metacestode that is either a cysticercus or a form derived from a bladder-like larva; no other unequivocal synapomorphies are evident. Tree structure provides no support for recognition of a diversity of tribes or genera within the Taeniinae: Fimbriotaeniini and Taeniini have no phylogenetic basis. Hydatigera, Fimbriotaenia, Fossor, Monordotaenia, Multiceps, Taeniarhynchus, Tetratirotaenia must be subsumed within Taenia as synonyms. Taenia saginata and Taenia asiatica are sister species and distantly related to Taenia solium. Cospeciation with respect to carnivorous definitive hosts and Taenia appears to be limited. Although felids are putative ancestral hosts, contemporary associations appear to have resulted from extensive host-switching among felids, canids, hyaenids, and others. In contrast, relationships with herbivorous intermediate hosts are indicative of more pervasive coevolution; rodents as intermediate hosts are postulated as ancestral for the Taeniidae, Taenia + Echinococcus. Patterns appear consistent with rapid shifts between phylogenetically unrelated carnivores but among those that historically exploited a common prey resource within communities in specific biogeographic regions.


Assuntos
Mamíferos/parasitologia , Filogenia , Taenia/classificação , Teníase/parasitologia , Animais , Interações Hospedeiro-Parasita , Humanos , Taenia/anatomia & histologia
18.
J Parasitol ; 86(1): 153-6, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10701580

RESUMO

As part of a continuing and more general study of the diversity of parasites from subterranean mammals in central North America, individuals of the Plains Pocket Gopher, Geomys bursarius bursarius, were collected from 7 localities in northwestern Minnesota from September 1991 through October 1996. Arthropods collected included the fleas, Opisocrostis bruneri (4 of 124, 3.2%), Foxella ignota ignota (85 of 124, 68.5%); the chewing louse, Geomydoecus geomydis geomydis from 98 of 124 (79%), and larvae of the tick, Dermacentor variabilis (1 of 124, 0.8%). Nematodes found included Physaloptera limbata (2 of 118 gophers, 1.7%), Capillaria americana (4 of 118, 3.4%), and Ransomus rodentorum (31 of 118, 26.3%). Cestodes recovered included Anoplocephaloides infrequens (12 of 136 gophers, 8.8%), Anoplocephaloides variabilis (19 of 136, 14%), Andrya macrocephala (20 of 136, 14.7%), and Hymenolepis weldensis from 12 of 136, 8.8%. The acanthocephalan, Moniliformis clarki was found in 1 of 118 gophers (0.8%). No parasites were found in the cheek pouches, thoracic, or peritoneal cavities.


Assuntos
Artrópodes/classificação , Ectoparasitoses/veterinária , Helmintíase Animal/parasitologia , Helmintos/classificação , Enteropatias Parasitárias/veterinária , Doenças dos Roedores/parasitologia , Acantocéfalos/isolamento & purificação , Animais , Cestoides/isolamento & purificação , Dermacentor , Ectoparasitoses/epidemiologia , Ectoparasitoses/parasitologia , Helmintíase Animal/epidemiologia , Helmintos/isolamento & purificação , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Minnesota/epidemiologia , Nematoides/isolamento & purificação , Ftirápteros , Prevalência , Doenças dos Roedores/epidemiologia , Roedores , Sifonápteros
19.
J Parasitol ; 86(6): 1326-35, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11191911

RESUMO

The phylogenetic relationships of 14 species of Stilestrongylus were analyzed using the comparative morphology of 21 characters. We obtained 2 shortest trees of 50 steps, with a consistency index of 0.540 and 25 apomorphic character states. Ingroup monophyly was supported on these trees by 2 and 3 synapomorphies, respectively, and the ingroup was defined by the following characters: greater number of ventral ridges relative to the number of ridges dorsally, asymmetric bursa, and externodorsal rays differing in size. Sister-group relationships among Stilestrongylus and the other genera designated as outgroups are relatively consistent with those postulated by Durette-Desset's in a classification of the Nippostrongylinae. The ancestor of the species groups comprising Hassalstrongylus, Guerrerostrongylus, and Stilestrongylus originated and diversified in murids in the Neotropical region. Species of Hassalstrongylus occur in rodents between southeastern North America and the eastern part of South America (Brazil and Argentina), whereas species of Guerrerostrongylus and Stilestrongylus diversified exclusively in rodents in the Neotropics.


Assuntos
Muridae/parasitologia , Filogenia , Doenças dos Roedores/parasitologia , Trichostrongyloidea/classificação , Tricostrongiloidíase/veterinária , Animais , Feminino , Masculino , México/epidemiologia , Doenças dos Roedores/epidemiologia , América do Sul/epidemiologia , Trichostrongyloidea/anatomia & histologia , Tricostrongiloidíase/epidemiologia , Tricostrongiloidíase/parasitologia , Clima Tropical
20.
Syst Parasitol ; 42(1): 1-12, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10613542

RESUMO

Evolutionary relationships of the Eucestoda have received intense but sporadic attention over the past century. Since 1996, the landscape has dramatically changed with respect to our knowledge of the phylogenetic relationships among the tapeworms. The 2nd International Workshop for Tapeworm Systematics (IWTS) held in Lincoln, Nebraska in October of that year provided the catalyst for development of novel hypotheses for inter- and intraordinal phylogeny. The working-group structure of the 2nd IWTS and results of phylogenetic studies are briefly introduced in the present manuscript. Higher-level phylogenies derived from parsimony analysis of independent data bases representing comparative morphology or molecular sequences were largely congruent and supported monophyly for the Eucestoda. The Caryophyllidea are basal; difossate forms such as the Pseudophyllidea are primitive; tetrafossates including the Tetraphyllidea, Proteocephalidea, Nippotaeniidea, Tetrabothriidea and Cyclophyllidea are derived; and hypotheses differed in the placement of the Trypanorhyncha and the Diphyllidea. These studies may provide a foundation for resolution of inter- and intra-ordinal relationships for the tapeworms. Additionally, the first comprehensive phylogenetic hypotheses for the Pseudophyllidea, Diphyllidea, Trypanorhyncha, the paraphyletic Tetraphyllidea + Lecanicephalidea, Proteocephalidea and Cyclophyllidea were developed during and subsequent to the 2nd IWTS. The stage is now set for continued and rapid advances in our understanding of the eucestodes. These studies have also served to re-emphasise the rich genealogical diversity of tapeworms and the temporally deep history for their origin. A co-evolutionary history and radiation of eucestodes may involve deep co-speciation with vertebrate host taxa, accompanied by some level of colonisation and extinction, extending into the Palaeozoic, minimally 350-420 million years ago.


Assuntos
Cestoides/classificação , Filogenia , Vertebrados/classificação , Animais
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