Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Fish Biol ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480996

RESUMO

Members of the genus Cyprinion (Cypriniformes: Cyprinidae) are found in the Indus River basin west to the Arabian Peninsula and the Tigris-Euphrates River drainages (Persian Gulf basin). The taxonomic status of Cyprinion including Cyprinion muscatense is poorly understood when compared to other cyprinid genera. C. muscatense has been considered as a member of the Cyprinion watsoni-microphthalmum group and a valid species endemic to the Arabian Peninsula. Here, we redescribe C. muscatense based on an integrative morphological and molecular approach and freshly sampled material from several localities in the Oman Mountains ecoregion. The results showed that C. muscatense is distinguished from the other Cyprinion species in the Arabian Peninsula by having a short, thin, and slightly serrated last unbranched dorsal fin ray; the lower number of circumpeduncular scales; lateral line scales; and also scales between the lateral line and the dorsal-fin origin. Subterminal mouth, presence of one pair of small barbels at the mouth corner, 3-4 unbranched and 9½-10½ dorsal-fin branched rays, 12-14 pectoral-fin rays, 7-8 pelvic-fin rays, 2-3 unbranched and 6½-7½ branched anal-fin rays, and 37-40 lateral line scales are other morphological characteristics of C. muscatense. C. muscatense is also well distinguished by molecular characters among its congeners. The first molecular phylogenetic analysis of the genus, covering all currently recognized Cyprinion species except for C. watsoni, is also presented. C. muscatense is resolved as the sister species to another endemic fish of the Arabian Peninsula Cyprinion mhalense, with a Kimura-2-Parameter model distance of 5.3%.

2.
Diagnostics (Basel) ; 13(9)2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37175033

RESUMO

In children born with cleft lip and palate, the timing of the secondary alveolar bone graft (SABG) is crucial to its success; this involves estimating the eruption of the permanent maxillary canine. Altered dental eruption in this patient group gives impetus to the identification of dental developmental factors concerning maxillary canine eruption, which may steer the clinical decision of SABG timing. Records of over nine hundred patients who received SABG with pre- and post-operative cone beam computed tomography (CBCT) scans were analyzed for inclusion and divided into two groups (erupting or non-erupting canine after SABG). Roots of the maxillary canines and premolars were segmented from the cementoenamel junction then linear and volumetric measurements were performed. The pre- and post-operative root length and volume differences were calculated and compared statistically using independent sample tests and paired t-tests. No statistically significant differences were found in the volume change (%), or reciprocal of mean root length in the erupted and unerupted groups in the canine, first premolar, or second premolar roots except for an association between the post-operative dental root length of the canine and the maxillary canine eruption status. Therefore, assessment of root development from pre-treatment CBCT scans was not deemed worthy from a diagnostic perspective.

3.
Zootaxa ; 5389(4): 473-482, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38221009

RESUMO

The type series of Poromitra crassiceps (Gnther, 1878) was thought to include specimens from four localities in the Atlantic, Pacific, and Southern oceans. Comparison of the extant syntypes with the original description revealed that the specimen from the Pacific Ocean was not included in the original type series; one syntype from the Atlantic Ocean was never incorporated into the collection of the Natural History Museum, London, and is considered lost, and another cannot be identified due to its bad condition. The fourth syntype, from the Southern Ocean and in the best condition, is designated lectotype of this species. Molecular analysis of tissue samples collected by us as well as publically available COI sequences showed that only one species, P. crassiceps, is currently known from the Southern Ocean. Specimens from this ocean named P. atlantica (Norman, 1929) in the literature and in collections are probably misidentifications of P. crassiceps. The validity of P. atlantica needs confirmation from fresh material from the type locality.


Assuntos
Peixes , Museus , Animais
4.
Zootaxa ; 5196(1): 46-60, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37044400

RESUMO

A study of the type series of Stylophthalmus paradoxus and Idiacanthus atlanticus (Stomiidae), and Cyclothone livida, C. obscura and C. pallida (Gonostomatidae), uncovered errors in the synonymy of Idiacanthus and inconsistencies regarding the number of type specimens of the three species of Cyclothone. The syntypes of S. paradoxus were matched with the illustrations of this species in Brauer (1906) and the specimen used in the description was identified and designated as a lectotype of this species. A comparison of these syntypes with specimens of Idiacanthus atlanticus, including its syntypes, and of I. fasciola indicated that S. paradoxus is most likely a junior synonym of I. fasciola. In addition, the research resulted in a reliable way to distinguish between I. fasciola and I. atlanticus and in the identification of the primary type of the latter species. Mismatches were found in the information Brauer (1906) provided about the material he had for the three species of Cyclothone as well as with published data about the type series of these species. It seems that the whereabouts of many of the type series specimens is unknown. We therefore propose that the individual specimens Brauer singled out for measurements in his original descriptions of C. livida, C. obscura and C. pallida be recognized as lectotypes.


Assuntos
Peixes , Animais , Peixes/classificação
6.
J Fish Biol ; 99(4): 1446-1454, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34269417

RESUMO

The accuracy and reliability of DNA metabarcoding analyses depend on the breadth and quality of the reference libraries that underpin them. However, there are limited options available to obtain and curate the huge volumes of sequence data that are available on public repositories such as NCBI and BOLD. Here, we provide a pipeline to download, clean and annotate mitochondrial DNA sequence data for a given list of fish species. Features of this pipeline include (a) support for multiple metabarcode markers; (b) searches on species synonyms and taxonomic name validation; (c) phylogeny assisted quality control for identification and removal of misannotated sequences; (d) automatically generated coverage reports for each new GenBank release update; and (e) citable, versioned DOIs. As an example we provide a ready-to-use curated reference library for the marine and freshwater fishes of the U.K. To augment this reference library for environmental DNA metabarcoding specifically, we generated 241 new MiFish-12S sequences for 88 U.K. marine species, and make available new primer sets useful for sequencing these. This brings the coverage of common U.K. species for the MiFish-12S fragment to 93%, opening new avenues for scaling up fish metabarcoding across wide spatial gradients. The Meta-Fish-Lib reference library and pipeline is hosted at https://github.com/genner-lab/meta-fish-lib.


Assuntos
Código de Barras de DNA Taxonômico , DNA Ambiental , Animais , Biodiversidade , Peixes/genética , Biblioteca Gênica , Reprodutibilidade dos Testes
7.
Artigo em Inglês | MEDLINE | ID: mdl-33684553

RESUMO

The olfactory epithelium of the sea catfish, Ariopsis felis, is found on a pinnate array of lamellae (the olfactory rosette) housed within a nasal chamber. The nasal anatomy of A. felis suggests an ability to capture external water currents. We prepared models from X-ray micro-computed tomography scans of two preserved specimens of A. felis. We then used dye visualisation and computational fluid dynamics to show that an external current induced a flow of water through a) the nasal chamber and b) the sensory channels of the olfactory rosette. The factors responsible for inducing flow through the nasal chamber are common to fishes from two other orders. The dye visualisation experiments, together with observations of sea catfishes in vivo, indicate that flow through the nasal chamber is regulated by a mobile nasal flap. The position of the nasal flap - elevated (significant flow) or depressed (reduced flow) - is controlled by the sea catfish's movements. Flow in the sensory channels of the olfactory rosette can pass through either a single channel or, via multiple pathways, up to four consecutive channels. Flow through consecutive sensory channels (olfactory resampling) is more extensive at lower Reynolds numbers (200 and 300, equivalent to swimming speeds of 0.5-1.0 total lengths s-1), coinciding with the mean swimming speed of the sea catfishes observed in vivo (0.6 total lengths s-1). Olfactory resampling may also occur, via a vortex, within single sensory channels. In conclusion, olfactory flow in the sea catfish is regulated and thoroughly sampled by novel mechanisms.


Assuntos
Peixes-Gato/fisiologia , Olfato/fisiologia , Animais , Modelos Anatômicos , Cavidade Nasal/anatomia & histologia , Cavidade Nasal/fisiologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-32171799

RESUMO

Olfactory flow in fishes is a little-explored area of fundamental and applied importance. We investigated olfactory flow in the pike, Esox lucius, because it has an apparently simple and rigid nasal region. We characterised olfactory flow by dye visualisation and computational fluid dynamics, using models derived from X-ray micro-computed tomography scans of two preserved specimens. An external current induced a flow of water through the nasal chamber at physiologically relevant Reynolds numbers (200-300). We attribute this externally-induced flow to: the location of the incurrent nostril in a region of high static pressure; the nasal bridge deflecting external flow into the nasal chamber; an excurrent nostril normal to external flow; and viscous entrainment. A vortex in the incurrent nostril may be instrumental in viscous entrainment. Flow was dispersed over the olfactory sensory surface when it impacted on the floor of the nasal chamber. Dispersal may be assisted by: the radial array of nasal folds; a complementary interaction between a posterior nasal fold and the ventral surface of the nasal bridge; and the incurrent vortex. The boundary layer could delay considerably (up to ~ 3 s) odorant transport from the external environment to the nasal region. The drag incurred by olfactory flow was almost the same as the drag incurred by models in which the nasal region had been replaced by a smooth surface. The boundary layer does not detach from the nasal region. We conclude that the nasal bridge and the incurrent vortex are pivotal to olfaction in the pike.


Assuntos
Esocidae/fisiologia , Cavidade Nasal/fisiologia , Nariz/fisiologia , Olfato/fisiologia , Microtomografia por Raio-X/métodos , Animais , Simulação por Computador , Esocidae/anatomia & histologia , Hidrodinâmica , Cavidade Nasal/anatomia & histologia , Nariz/anatomia & histologia , Natação/fisiologia
9.
Oral Maxillofac Surg Clin North Am ; 32(2): 233-247, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32081578

RESUMO

This article provides an overview of epidemiology, genetics, and common orofacial features of those with craniosynostosis. Patients with craniosynostosis require several surgical procedures along with continuum of care. The earliest surgical interventions are done during the first few years of life to relieve the fused sutures. Midface advancement, limited phase of orthodontic treatment, and combined orthodontics/orthognathic surgery treatment are usually required during later years. This article presents several examples of cases with outcomes associated with these procedures.


Assuntos
Craniossinostoses/cirurgia , Procedimentos Cirúrgicos Ortognáticos , Osteogênese por Distração , Humanos , Síndrome
10.
Oral Maxillofac Surg Clin North Am ; 32(2): 205-217, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32098718

RESUMO

This article provides an overview of the orthodontic preparation prior to secondary alveolar bone grafting of alveolar defects in those with complete cleft lip and palate. Use of cone beam computed tomography in diagnosis and treatment planning for addressing alveolar clefts, the rationale for maxillary expansion prior to alveolar bone grafting, key steps in differential maxillary expansion, potential adverse effects, and outcomes associated with maxillary expansion are provided in this overview.


Assuntos
Enxerto de Osso Alveolar , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Humanos , Técnica de Expansão Palatina
11.
Artigo em Inglês | MEDLINE | ID: mdl-31229600

RESUMO

Fluid dynamics plays an important part in olfaction. Using the complementary techniques of dye visualisation and computational fluid dynamics (CFD), we investigated the hydrodynamics of the nasal region of the sturgeon Huso dauricus. H. dauricus offers several experimental advantages, including a well-developed, well-supported, radial array (rosette) of visible-by-eye olfactory sensory channels. We represented these features in an anatomically accurate rigid model derived from an X-ray scan of the head of a preserved museum specimen. We validated the results from the CFD simulation by comparing them with data from the dye visualisation experiments. We found that flow through both the nasal chamber and, crucially, the sensory channels could be induced by an external flow (caused by swimming in vivo) at a physiologically relevant Reynolds number. Flow through the nasal chamber arises from the anatomical arrangement of the incurrent and excurrent nostrils, and is assisted by the broad, cartilage-supported, inner wall of the incurrent nostril. Flow through the sensory channels arises when relatively high speed flow passing through the incurrent nostril encounters the circular central support of the olfactory rosette, decelerates, and is dispersed amongst the sensory channels. Vortices within the olfactory flow may assist odorant transport to the sensory surfaces. We conclude that swimming alone is sufficient to drive olfactory flow in H. dauricus, and consider the implications of our results for the three other extant genera of sturgeons (Acipenser, Pseudoscaphirhynchus and Scaphirhynchus), and for other fishes with olfactory rosettes.


Assuntos
Peixes/fisiologia , Nariz/fisiologia , Odorantes , Olfato/fisiologia , Animais , Simulação por Computador , Modelos Anatômicos , Cavidade Nasal/fisiologia , Natação/fisiologia
12.
Zootaxa ; 4173(1): 75-84, 2016 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-27701205

RESUMO

The Australasian Saratoga (Pisces: Osteoglossidae) is currently recognised as comprised of two species Scleropages leichardti and S. jardinii. The Prussian explorer Ludwig Leichhardt (1813-c.1848) collected specimens of both species on his first major expedition across northern Australia but believed at the time that all specimens collected were from within one species. Details of the fate of these specimens are unclear as is the geographic origin of those specimens that ultimately made their way into museum collections. Günther's 1864 description of the Southern Saratoga S. leichardti, purportedly from the Fitzroy River in Queensland to which it is restricted (although he erred and listed it as the Burdekin River) is meagre and inconsistent with contemporary accounts of the morphology of this species. It is also inconsistent with a subsequent description by de Castelnau in 1876 of the supposedly synonymous Osteoglossum guntheri. Finally, the description of S. leichardti by Günther is largely consistent with meristic and morphometric information within Saville-Kent's (1892) description of the wide-spread Northern Saratoga S. jardinii. On balance, these inconsistencies, doubt about the provenance and geographic origin of type material and provenance of the original descriptions all strongly suggest that Günther based his description of S. leichardti on material collected from within the range of the more widespread taxon currently recognised as S. jardinii. A revision of the Australian species within the genus Scleropages is warranted.


Assuntos
Peixes/classificação , Distribuição Animal , Animais , Austrália , Peixes/anatomia & histologia , Geografia , Rios
13.
Zoology (Jena) ; 119(6): 500-510, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27449820

RESUMO

Fishes have several means of moving water to effect odorant transport to their olfactory epithelium ('olfactory flow'). Here we show that olfactory flow in the adult garpike Belone belone (Belonidae, Teleostei), a fish with an unusual nasal region, can be generated by its motion relative to water (swimming, or an external current, or both). We also show how the unusual features of the garpike's nasal region influence olfactory flow. These features comprise a triangular nasal cavity in which the olfactory epithelium is exposed to the external environment, a papilla situated within the nasal cavity, and an elongated ventral apex. To perform our investigation we first generated life-like plastic models of garpike heads from X-ray scans of preserved specimens. We then suspended these models in a flume and flowed water over them to simulate swimming. By directing filaments of dye at the static models, we were able to visualise flow in the nasal regions at physiologically relevant Reynolds numbers (700-2,000). We found that flow of water over the heads did cause circulation in the nasal cavity. Vortices may assist in this circulation. The pattern of olfactory flow was influenced by morphological variations and the asymmetry of the nasal region. The unusual features of the nasal region may improve odorant sampling in the garpike, by dispersing flow over the olfactory epithelium and by creating favourable conditions for odorant transport (e.g. steep velocity gradients). Unexpectedly, we found that the mouth and the base of the garpike's jaws may assist the sampling process. Thus, despite its apparent simplicity, the garpike's nasal region is likely to act as an effective trap for odorant molecules.


Assuntos
Peixes/anatomia & histologia , Peixes/fisiologia , Nariz/anatomia & histologia , Nariz/fisiologia , Animais , Cabeça , Modelos Anatômicos , Olfato , Natação , Movimentos da Água
14.
Artigo em Inglês | MEDLINE | ID: mdl-26780177

RESUMO

Scent detection in an aquatic environment is dependent on the movement of water. We set out to determine the mechanisms for moving water through the olfactory organ of guitarfishes (Rhinobatidae, Chondrichthyes) with open nasal cavities. We found at least two. In the first mechanism, which we identified by observing dye movement in the nasal region of a life-sized physical model of the head of Rhinobatos lentiginosus mounted in a flume, olfactory flow is generated by the guitarfish's motion relative to water, e.g. when it swims. We suggest that the pressure difference responsible for motion-driven olfactory flow is caused by the guitarfish's nasal flaps, which create a region of high pressure at the incurrent nostril, and a region of low pressure in and behind the nasal cavity. Vortical structures in the nasal region associated with motion-driven flow may encourage passage of water through the nasal cavity and its sensory channels, and may also reduce the cost of swimming. The arrangement of vortical structures is reminiscent of aircraft wing vortices. In the second mechanism, which we identified by observing dye movement in the nasal regions of living specimens of Glaucostegus typus, the guitarfish's respiratory pump draws flow through the olfactory organ in a rhythmic (0.5-2 Hz), but continuous, fashion. Consequently, the respiratory pump will maintain olfactory flow whether the guitarfish is swimming or at rest. Based on our results, we propose a model for olfactory flow in guitarfishes with open nasal cavities, and suggest other neoselachians which this model might apply to.


Assuntos
Peixes/fisiologia , Cavidade Nasal/fisiologia , Olfato/fisiologia , Animais , Peixes/metabolismo , Cavidade Nasal/metabolismo , Respiração , Natação/fisiologia , Água/metabolismo
15.
Br J Oral Maxillofac Surg ; 51(8): 841-4, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23962594

RESUMO

We aimed to gather data on the current practice of surgically assisted rapid maxillary expansion (SARME) in the UK. Surveys were posted in the mail to all members of the British Association of Oral and Maxillofacial Surgeons (n=379) and 166 (44%) responded. In the previous year 69 responders (42%) had done at least one SARME operation. The technique used by individual surgeons may be more experience-based than evidence-based, which leads to considerable variation.


Assuntos
Maxila/cirurgia , Osteogênese por Distração/estatística & dados numéricos , Técnica de Expansão Palatina/estatística & dados numéricos , Humanos , Desenho de Aparelho Ortodôntico/estatística & dados numéricos , Osteogênese por Distração/instrumentação , Técnica de Expansão Palatina/instrumentação , Padrões de Prática Odontológica/estatística & dados numéricos , Fatores de Tempo , Reino Unido
16.
J Morphol ; 274(9): 987-1009, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23630172

RESUMO

Holocephalans (chimaeras) are a group of marine fishes comprising three families: the Callorhinchidae (callorhinchid fishes), the Rhinochimaeridae (rhinochimaerid fishes) and the Chimaeridae (chimaerid fishes). We have used X-ray microcomputed tomography and magnetic resonance imaging to characterise in detail the nasal anatomy of three species of chimaerid fishes: Chimaera monstrosa, C. phantasma and Hydrolagus colliei. We have shown that the nasal chamber of these three species is linked to the external environment by an incurrent channel and to the oral cavity by an excurrent channel via an oral groove. A protrusion of variable morphology is present on the medial wall of the incurrent channel in all three species, but is absent in members of the two other holocephalan families that we inspected. A third nasal channel, the lateral channel, functionally connects the incurrent nostril to the oral cavity, by-passing the nasal chamber. From anatomical reconstructions, we have proposed a model for the circulation of water, and therefore the transport of odorant, in the chimaerid nasal region. In this model, water could flow through the nasal region via the nasal chamber or the lateral channel. In either case, the direction of flow could be reversed. Circulation through the entire nasal region is likely to be driven primarily by the respiratory pump. We have identified several anatomical features that may segregate, distribute, facilitate and regulate flow in the nasal region and have considered the consequences of flow reversal. The non-sensory cilia lining the olfactory sensory channels appear to be mucus-propelling, suggesting that these cilia have a common protective role in cartilaginous fishes (sharks, rays and chimaeras). The nasal region of chimaerid fishes shows at least two adaptations to a benthic lifestyle, and suggests good olfactory sensitivity, with secondary folding enhancing the hypothetical flat sensory surface area by up to 70%.


Assuntos
Peixes/anatomia & histologia , Adaptação Fisiológica , Animais , Cílios , Imageamento por Ressonância Magnética , Cavidade Nasal/anatomia & histologia , Cavidade Nasal/fisiologia , Tubarões/fisiologia , Olfato/fisiologia , Movimentos da Água , Microtomografia por Raio-X
17.
Eur J Orthod ; 35(2): 169-74, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22467569

RESUMO

Orthodontic tooth movement is dependent upon the ability of mechanical forces to induce remodelling activity within the tooth-supporting alveolar bone. In view of the importance of bone resorption in mediating tooth movement, the aim of this study was to establish if alterations in the osteoclast-specific bone marker tartrate-resistant acid phosphatase (TRACP) 5b could be detected in the sera of patients undergoing orthodontic treatment. The sample consisted of 14 subjects (10 girls and 4 boys) aged 10.5-16.5 years (mean 12.6 years) being treated with fixed appliances and a distalizing headgear. Venous blood samples (3 ml) were collected from the cubital vein pre-treatment (T0) and 2, 4, and 6 months into treatment (T1-T3); serum TRACP 5b levels were quantified using a solid-phase immunofixed enzyme activity assay. When the data were pooled and treated cross-sectionally, a significant increase in immunoreactive TRACP 5b was detected at 2 months (T1) indicating increased bone resorptive activity. However, when the serum profiles of individual patients were recorded longitudinally, a very different pattern emerged, not all patients following the same trend. This is not surprising given normal anatomical variation and differences between the patients in age, gender, and mechanotherapy. Designed as a pilot to demonstrate 'proof of principle', this study is the first to show that the TRACP 5b isoform can be detected in the sera of patients undergoing orthodontic treatment. It further suggests that serum bone marker measurements offer a simple and minimally invasive method for correlating the findings of laboratory and animal experimentation with clinical data.


Assuntos
Fosfatase Ácida/sangue , Reabsorção Óssea/enzimologia , Isoenzimas/sangue , Técnicas de Movimentação Dentária , Adolescente , Biomarcadores/sangue , Reabsorção Óssea/sangue , Criança , China , Feminino , Humanos , Masculino , Osteoclastos/enzimologia , Fosfatase Ácida Resistente a Tartarato
18.
Artigo em Inglês | MEDLINE | ID: mdl-19883784

RESUMO

We describe several novel morphological features in the nasal region of the hammerhead shark Sphyrna tudes. Unlike the open, rounded incurrent nostril of non-hammerhead shark species, the incurrent nostril of S. tudes is a thin keyhole-like aperture. We discovered a groove running anterior and parallel to the incurrent nostril. This groove, dubbed the minor nasal groove to distinguish it from the larger, previously described, (major) nasal groove, is common to all eight hammerhead species. Using life-sized plastic models generated at 200 microm resolution from an X-ray scan, we also investigated flow in the nasal region. Even modest oncoming flow speeds stimulate extensive, but not complete, circulation within the model olfactory chamber, with flow passing through the two main olfactory channels. Flow crossed from one channel to another via a gap in the olfactory array, sometimes guided by the interlamellar channels. Major and minor nasal grooves, as well as directing flow into the olfactory chamber, can, in conjunction with the nasal bridge separating incurrent and excurrent nostrils, limit flow passing into the olfactory chamber, possibly to protect the delicate nasal structures. This is the first simulation of internal flow within the olfactory chamber of a shark.


Assuntos
Nariz/anatomia & histologia , Nariz/fisiologia , Tubarões/anatomia & histologia , Tubarões/fisiologia , Olfato , Animais , Modelos Anatômicos , Nariz/diagnóstico por imagem , Condutos Olfatórios/anatomia & histologia , Condutos Olfatórios/fisiologia , Ventilação Pulmonar , Reologia , Natação , Gravação em Vídeo , Microtomografia por Raio-X
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...