Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Int J Parasitol Parasites Wildl ; 10: 218-230, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31667085

RESUMO

Lucilia (Diptera: Calliphoridae) is a genus of blowflies comprised largely of saprophagous and facultative parasites of livestock. Lucilia bufonivora, however, exhibits a unique form of obligate parasitism of amphibians, typically affecting wild hosts. The evolutionary route by which amphibian myiasis arose, however, is not well understood due to the low phylogenetic resolution in existing nuclear DNA phylogenies. Furthermore, the timing of when specificity for amphibian hosts arose in L. bufonivora is also unknown. In addition, this species was recently reported for the first time in North America (Canada) and, to date, no molecular studies have analysed the evolutionary relationships between individuals from Eastern and Western hemispheres. To provide broader insights into the evolution of the amphibian parasitic life history trait and to estimate when the trait first arose, a time-scaled phylogeny was inferred from a concatenated data set comprising mtDNA, nDNA and non-coding rDNA (COX1, per and ITS2 respectively). Specimens from Canada, the UK, Poland, Switzerland, the Netherlands and Germany were analysed, as well as individuals from its sister taxa, the saprophage Lucilia silvarum and a Nearctic species also implicated in amphibian myiasis, Lucilia elongata. Obligate amphibian parasitism appears to have arisen ~4 mya, likely as a result of niche displacement of a saprophagous/facultative parasite ancestor. Consistent paraphyly of L. bufonivora with respect to L. elongata across single-gene phylogenies and high mtDNA genetic distances between Nearctic and Palearctic individuals suggest on-going cryptic speciation facilitated by geographical isolation. These findings suggest that recent reports of L. bufonivora in the Nearctic do not constitute a recent introduction, but instead suggest that it remained unrecorded due to taxonomic confusion and low abundance. This is the first study to confirm the involvement of L. bufonivora in amphibian myiasis in Canada using DNA-based identification methods.

2.
Parasitol Res ; 113(5): 1629-40, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24553979

RESUMO

There are only three fly species that are obligate agents of traumatic myiasis of humans and livestock: a single species of flesh fly, Wohlfahrtia magnifica (Sarcophagidae), and two species of blow flies, Chrysomya bezziana and Cochliomyia hominivorax (Calliphoridae). The morphology of their first instar larvae is thoroughly and consistently documented here with light microscopy photographs and scanning electron microscopy micrographs. The following morphological structures are documented: pseudocephalon, antennal complex, maxillary palpus, oral ridges, thoracic and abdominal spinulation, spiracular field, posterior spiracles and cephaloskeleton. New diagnostic features drawn from the cephaloskeleton and the spinulation of abdominal segments, including the anal pad, are discovered and extensively described. Earlier descriptions in the literature are revisited, and major discrepancies between these and the results of the current study are discussed. The present results allow clarification, correction and, especially, complementation of information provided by earlier authors. The relatively distant taxonomic position of all three species is evidence that obligatory myiasis has arisen independently, and the extensively similar morphology in the first instar larvae of Chrysomya bezziana, Cochliomyia hominivorax and W. magnifica in comparison to necrophagous species, especially the enhancement of the anterior part of the cephaloskeleton and the segmental spinulation, is therefore best interpreted as homoplasic adaptations to a life strategy as obligate vertebrate parasites. An identification key for first instar larvae of all obligatory traumatic myiasis agents of mammals is provided.


Assuntos
Dípteros/anatomia & histologia , Sarcofagídeos/anatomia & histologia , Animais , Dípteros/ultraestrutura , Larva/anatomia & histologia , Microscopia , Microscopia Eletrônica de Varredura , Miíase/parasitologia , Sarcofagídeos/ultraestrutura
3.
Med Vet Entomol ; 28(2): 133-42, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23834428

RESUMO

First instars of Calliphora vomitoria (Linnaeus) and Cynomya mortuorum (Linnaeus) (both: Diptera: Calliphoridae) are thoroughly documented with scanning electron microscopy images, light microscopy photographs and line drawings. Substantial new data are provided for the following morphological structures: pseudocephalon; antennal complex; maxillary palpus; facial mask; cephaloskeleton; thoracic and abdominal spinulation; spiracular field, and posterior spiracles. Earlier descriptions are summarized and major discrepancies with the current study are discussed. An identification key to first-instar larvae of the five European species of Calliphorinae of forensic importance is presented. However, it remains impossible to distinguish the first instars of Ca. vicina and Cy. mortuorum based on external morphology with the current level of knowledge.


Assuntos
Dípteros/anatomia & histologia , Dípteros/classificação , Ciências Forenses , Animais , Dípteros/crescimento & desenvolvimento , Dípteros/ultraestrutura , Europa (Continente) , Larva/anatomia & histologia , Larva/classificação , Larva/crescimento & desenvolvimento , Larva/ultraestrutura , Região do Mediterrâneo , Microscopia Eletrônica de Varredura , Polônia , Especificidade da Espécie
4.
Med Vet Entomol ; 27(2): 181-93, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22827166

RESUMO

Light microscopy photographs, line illustrations and scanning electron micrographs are provided for first instars of Chrysomya albiceps (Wiedemann), Chrysomya megacephala (Fabricius) and Protophormia terraenovae (Robineau-Desvoidy) (all: Diptera: Calliphoridae). The following morphological structures are documented: pseudocephalon; antennal complex; maxillary palpus; facial mask; thoracic and abdominal spinulation; spiracular field; posterior spiracles, and cephaloskeleton. New diagnostic features of the cephaloskeleton and the spinulation of abdominal segments are described. Verification of earlier descriptions revealed major discrepancies among published data. The present results allow for the clarification, correction and, especially, complementation of existing information provided by numerous authors. Finally, an identification key for first-instar larvae of European and Mediterranean Chrysomyinae of forensic importance is presented.


Assuntos
Dípteros/anatomia & histologia , Dípteros/classificação , Animais , Dípteros/crescimento & desenvolvimento , Larva/anatomia & histologia , Larva/classificação , Larva/crescimento & desenvolvimento , Microscopia Eletrônica de Varredura , Especificidade da Espécie
5.
Med Vet Entomol ; 27(4): 349-66, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23205742

RESUMO

First instars of Lucilia ampullacea Villeneuve, Lucilia caesar Linnaeus, Lucilia cuprina Weidemann, Lucilia richardsi Collin, Lucilia sericata Meigen and Lucilia silvarum Meigen (Diptera: Calliphoridae) are thoroughly documented with scanning electron microscopy images, light microscopy photographs and line drawings. The following morphological structures are documented: pseudocephalon, antennal complex, maxillary palpus, facial mask, cephaloskeleton, thoracic and abdominal spinulation, spiracular field, and posterior spiracles. New diagnostic features of the cephaloskeleton are presented and the spinulation of the abdominal segments is described. Earlier descriptions are summarized and major discrepancies with the current study are discussed. The present results allow for the clarification, correction and, especially, complementing existing information provided by numerous authors. The first instar larva of L. richardsi is described for the first time and an identification key to the first instars of European species of Lucilia Robineau-Desvoidy of forensic importance is presented.


Assuntos
Dípteros/anatomia & histologia , Dípteros/classificação , Medicina Legal , Animais , Europa (Continente) , Larva/anatomia & histologia , Larva/classificação , Região do Mediterrâneo , Especificidade da Espécie
6.
Med Vet Entomol ; 26(1): 70-82, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21707683

RESUMO

The morphology of all larval instars of Fannia canicularis (Linnaeus) (Diptera: Fanniidae) is documented using a combination of light and scanning electron microscopy. The following structures are documented for all instars: antennal complex; maxillary palpus; facial mask; cephaloskeleton; ventral organ; anterior spiracle; Keilin's organ; posterior spiracle; fleshy processes, and anal pad. Structures reported for the first time for all instars include: two pairs of lateral prominences on the prothoracic segment; additional ventrolateral prominences on the second thoracic segment, and a papilla at the base of the posterior spiracle. Other structures reported for the first time are anterior spiracles in the first instar and a serrated tip on the mouthhook in the second instar. A trichoid sensillum on the posterior spiracular plate, representing a sensory organ otherwise unknown in the Calyptratae, is described in the second and third instars. Results are discussed and compared with existing knowledge on dipteran larval morphology.


Assuntos
Dípteros/ultraestrutura , Animais , Dípteros/classificação , Larva/classificação , Larva/ultraestrutura , Especificidade da Espécie
7.
Med Vet Entomol ; 24(3): 278-83, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20557459

RESUMO

The first breeding records of miltogrammine fleshflies in buried vertebrate carrion are presented. First instars of Eumacronychia persolla Reinhard (Nearctic) (Diptera: Sarcophagidae) and Phylloteles pictipennis Loew (Palaearctic) (Diptera: Sarcophagidae) are able to penetrate dry, loose soil and reach deeply buried animal remains, an ability which distinguishes is unique to necrophagous Calyptratae. Their broad geographical distribution, fast location and colonization of carrion, complete development on buried food resources and easy identification make these species useful forensic indicators in buried bodies in dry habitats.


Assuntos
Dípteros , Ciências Forenses/métodos , Animais , Sepultamento , Larva , Mudanças Depois da Morte , Ratos , Suínos , Fatores de Tempo
8.
Med Vet Entomol ; 22(1): 16-25, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18380650

RESUMO

Scanning electron microscopy documentation of first instar Calliphora vicina Robineau-Desvoidy, Phormia regina (Meigen) and Lucilia illustris (Meigen) (Diptera: Calliphoridae) is presented for the first time, and the following morphological structures are documented: pseudocephalon; antenna; maxillary palpus; facial mask; labial lobe; thoracic and abdominal spinulation; spiracular field; posterior spiracles, and anal pad. Light microscopy documentation and illustrations are provided for the cephaloskeleton in lateral and ventral views. New diagnostic features are revealed in the configuration of the facial mask, cephaloskeleton and posterior spiracles. The first instar morphology of C. vicina, Ph. regina and L. illustris is discussed in the light of existing knowledge about early instars of blowflies.


Assuntos
Dípteros/anatomia & histologia , Dípteros/ultraestrutura , Animais , Feminino , Insetos Vetores/anatomia & histologia , Insetos Vetores/ultraestrutura , Larva/anatomia & histologia , Larva/ultraestrutura , Microscopia Eletrônica de Varredura , Pupa/anatomia & histologia , Pupa/ultraestrutura
9.
Probl Med Wieku Rozwoj ; 11: 83-96, 1982.
Artigo em Polonês | MEDLINE | ID: mdl-7178093

RESUMO

The x-ray investigations are performed in every case of urolithiasis. The basic ones are plain films of abdomen, urography and voiding cystourethrography. These investigations do not establish the type of lithiasis, particularly in cases of mixed stones. A visualization of concrements on a plain film depends on the absorption coefficient of x-rays. There is a close connection between radiological morphology and chemical composition as well as structure of concrements. A precise determination of phase composition of stones and their structure is possible only in the indirect investigations, i.e. after concrements' extirpation. X-ray structural methods, infrared spectrometric method, thermal and optical ones in polarization light belong to indirect inquires. The diffractograms are a consequence of x-ray structural analysis. A comparison of them with specimens allows for identification of every crystallic substance. The principle of the infrared spectrometry is a selective absorption of infrared rays in substances of different chemical structures. A comparison of infrared absorption spectrum with specimens allows for identification of some substances. An advantage of this method is its high sensibility and the possibility to perform on a small quantity of substratum (1 mg). An optical method facilitates a microscopic observation of a thin plate of stone (0,02 mm) in the polarization passing light appropriate to qualify the basic optical properties of minerals. It is possible to see the inside of concrements in the relatively big magnification without destruction of its primary structure. The recognition of the main and subordinate components in renal stones is possible through the use of at least several very precise methods, from which x-ray structural analysis, optical and infrared absorption are of main importance.


Assuntos
Cálculos Urinários/diagnóstico , Adolescente , Apatitas/análise , Criança , Pré-Escolar , Cistina/análise , Feminino , Humanos , Masculino , Minerais/análise , Oxalatos/análise , Fosfatos/análise , Espectrofotometria Infravermelho , Ácido Úrico/análise , Cálculos Urinários/diagnóstico por imagem , Urografia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA