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1.
J Zoo Wildl Med ; 51(4): 868-878, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33480567

RESUMO

Lumholtz's tree-kangaroo (Dendrolagus lumholtzi) is one of two species of tree-kangaroos found in Queensland, Australia. There is little information about ocular anatomy and pathology in any species of tree-kangaroo, and there are claims of blindness from unknown causes in free-ranging Lumholtz's tree-kangaroos. This study investigated ocular anatomy and pathology in 80 individuals, using examination of 31 live animals and histopathologic examination of eyes from 49 carcasses. Tree-kangaroos were found to have a typical vertebrate eye with immuno-histochemical evidence for dichromatic color vision. Only 5.4% of animals had evidence of pathology from traumatic injury, infection, or a variety of nonspecific lesions. Toxoplasmosis was implicated in ocular lesions in three animals. This study did not find evidence of widespread blindness in free-ranging animals nor evidence of toxic optic neuropathy. Examinations of live animals highlighted the need to establish normal ocular examination parameters and vision testing protocols suitable for use in tree-kangaroos and the need for more comprehensive examination and testing of animals thought to have vision loss of unknown origin.


Assuntos
Oftalmopatias/veterinária , Olho/anatomia & histologia , Macropodidae , Animais , Animais Selvagens , Oftalmopatias/patologia , Feminino , Masculino , Queensland
2.
J Zoo Wildl Med ; 51(4): 879-888, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33480568

RESUMO

Ophthalmic studies of the Texas tortoise (Gopherus berlandieri) established normal ophthalmic parameters for select diagnostic tests in captive tortoises and assessment of differences among individuals of differing size and health status. Sixty-one tortoises of varying weight, shell size, Mycoplasma seroprevalence, and herpesvirus exposure were included. Complete ophthalmic examinations, including neuro-ophthalmic reflexes, phenol red thread test, rebound tonometry, fluorescein staining, palpebral fissure length measurement, slit lamp biomicroscopy, indirect fundoscopy, and ocular ultrasound measurements of axial globe length, anterior chamber depth, lens thickness, and vitreous length, were recorded. All tortoises had negative dazzle and pupillary light reflexes, inconsistent menace responses, and positive palpebral reflexes. Mean ± SD tear production and intraocular pressure (IOP) were 14.2 ± 5.6 mm/15 sec and 13.8 ± 2.4 mm Hg in healthy tortoises, respectively. Mycoplasma-seropositive tortoises (with or without herpesvirus exposure) had significantly increased tear production (20.2 ± 8.1 and 19.9 ± 8.9 mm/15 sec, respectively) compared with healthy seronegative tortoises (14.2 ± 5.6 mm/15 sec; P = 0.02). As body size decreased, so too did palpebral fissure length and ocular ultrasound measurements, while IOP increased. Overall, palpebral fissure length appeared relatively small, and tear production relatively increased compared with other chelonian species, likely on the basis of the relatively arid native habitat. Further work is recommended to establish baseline values in related species, as well as comparison in aquatic versus terrestrial chelonians. The authors further suggest that the finding of relatively increased tear production in tortoises may indicate the need to rule out mycoplasmosis as a cause of upper respiratory tract disease.


Assuntos
Olho/anatomia & histologia , Tartarugas/anatomia & histologia , Animais , Oftalmopatias/patologia , Feminino , Masculino , Mycoplasma/isolamento & purificação , Lágrimas , Tonometria Ocular
3.
JAMA ; 325(2): 164-174, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33433580

RESUMO

Importance: Glaucoma is the most common cause of irreversible blindness worldwide. Many patients with glaucoma are asymptomatic early in the disease course. Primary care clinicians should know which patients to refer to an eye care professional for a complete eye examination to check for signs of glaucoma and to determine what systemic conditions or medications can increase a patient's risk of glaucoma. Open-angle and narrow-angle forms of glaucoma are reviewed, including a description of the pathophysiology, risk factors, screening, disease monitoring, and treatment options. Observations: Glaucoma is a chronic progressive optic neuropathy, characterized by damage to the optic nerve and retinal nerve fiber layer, that can lead to permanent loss of peripheral or central vision. Intraocular pressure is the only known modifiable risk factor. Other important risk factors include older age, nonwhite race, and a family history of glaucoma. Several systemic medical conditions and medications including corticosteroids, anticholinergics, certain antidepressants, and topiramate may predispose patients to glaucoma. There are 2 broad categories of glaucoma, open-angle and angle-closure glaucoma. Diagnostic testing to assess for glaucoma and to monitor for disease progression includes measurement of intraocular pressure, perimetry, and optical coherence tomography. Treatment of glaucoma involves lowering intraocular pressure. This can be achieved with various classes of glaucoma medications as well as laser and incisional surgical procedures. Conclusions and Relevance: Vision loss from glaucoma can be minimized by recognizing systemic conditions and medications that increase a patient's risk of glaucoma and referring high-risk patients for a complete ophthalmologic examination. Clinicians should ensure that patients remain adherent with taking glaucoma medications and should monitor for adverse events from medical or surgical interventions used to treat glaucoma.


Assuntos
Glaucoma , Pressão Intraocular , Adulto , Progressão da Doença , Olho/anatomia & histologia , Glaucoma/complicações , Glaucoma/diagnóstico , Glaucoma/fisiopatologia , Glaucoma/terapia , Humanos , Programas de Rastreamento , Prognóstico , Fatores de Risco , Transtornos da Visão/etiologia , Transtornos da Visão/prevenção & controle
4.
Proc Biol Sci ; 287(1935): 20201393, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32962540

RESUMO

Frogs and toads (Amphibia: Anura) display diverse ecologies and behaviours, which are often correlated with visual capacity in other vertebrates. Additionally, anurans exhibit a broad range of relative eye sizes, which have not previously been linked to ecological factors in this group. We measured relative investment in eye size and corneal size for 220 species of anurans representing all 55 currently recognized families and tested whether they were correlated with six natural history traits hypothesized to be associated with the evolution of eye size. Anuran eye size was significantly correlated with habitat, with notable decreases in eye investment among fossorial, subfossorial and aquatic species. Relative eye size was also associated with mating habitat and activity pattern. Compared to other vertebrates, anurans have relatively large eyes for their body size, indicating that vision is probably of high importance. Our study reveals the role that ecology and behaviour may have played in the evolution of anuran visual systems and highlights the usefulness of museum specimens, and importance of broad taxonomic sampling, for interpreting macroecological patterns.


Assuntos
Anuros , Tamanho Corporal , Bufonidae , Ecossistema , Olho/anatomia & histologia , Animais , Evolução Biológica , Cruzamento , Fenótipo , Filogenia , Reprodução , Visão Ocular
5.
PLoS One ; 15(7): e0235984, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32658920

RESUMO

The stalk-eyed flies (Diopsidae, Diptera) are a family of approximately 100 species of calypterate dipterans, characterised by extended head capsules. Species within the family have previously been shown to possess six subfamilies of mariner transposons, with nucleotide substitution patterns suggesting that at least two subfamilies are currently active. The vertumnana subfamily has been shown to have been involved in a horizontal transfer event involving Diopsidae and a second dipteran family in the Tephritidae. Presented here are cloned and sequenced mariner elements from three further diopsid species, in addition to a bioinformatic analysis of mariner elements identified in transcriptomic and genomic data from the genus Teleopsis. The newly identified mariner elements predominantly fall into previously recognised subfamilies, however the publicly available Teleopsis data also revealed a novel subfamily. Three of the seven identified subfamilies are shown to have undergone horizontal transfer, two of which appear to involve diopsid donor species. One recipient group of a diopsid mariner is the Bactrocera genus of tephritid flies, the transfer of which was previously proposed in an earlier study of diopsid mariner elements. The second horizontal transfer, of the mauritiana subfamily, can be traced from the Teleopsis genus to the cnidarian Hydra vulgaris. The mauritiana elements are shown to be active in the recipient H. vulgaris and transposase expression is observed in all body tissues examined in both species. The increased diversity of diopsid mariner elements points to a minimum of four subfamilies being present in the ancestral genome. Both vertical inheritance and stochastic loss of TEs have subsequently occurred within the diopsid radiation. The TE complement of H. vulgaris contains at least two mariner subfamilies of insect origin. Despite the phylogenetic distance between donor and recipient species, both subfamilies are shown to be active and proliferating within H. vulgaris.


Assuntos
Elementos de DNA Transponíveis , Dípteros/genética , Evolução Molecular , Transferência Genética Horizontal , Genoma , Interações Hospedeiro-Patógeno/genética , Proteínas de Insetos/genética , Animais , Dípteros/classificação , Olho/anatomia & histologia , Olho/crescimento & desenvolvimento , Olho/metabolismo , Hydra/fisiologia , Filogenia
6.
PLoS One ; 15(6): e0235342, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32598385

RESUMO

This report elaborates on adaptations of the eyes of the whale shark Rhincodon typus (Elasmobranchii, Rhincodontidae), including the discovery that they are covered with dermal denticles, which is a novel mechanism of eye protection in vertebrates. The eye denticle differs in morphology from that of the dermal denticles distributed over the rest of the body, consistent with a different function (abrasion resistance). We also demonstrate that the whale shark has a strong ability to retract the eyeball into the eye socket. The retraction distance was calculated to be approximately half the diameter of the eye, which is comparable to those of other vertebrates that are known to have highly retractable eyes. These highly protective features of the whale shark eye seem to emphasize the importance of vision for environmental perception, which contradicts the general, though poorly established, notion of low reliance on vision in this species.


Assuntos
Movimentos Oculares/fisiologia , Olho/anatomia & histologia , Olho/fisiopatologia , Tubarões/anatomia & histologia , Tubarões/fisiologia , Animais
7.
Expert Rev Med Devices ; 17(6): 591-597, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32425075

RESUMO

PURPOSE: To assess the repeatability of ocular biometric parameters using a high-resolution imaging device. METHODS: 74 healthy right eyes were included in this study. Five-repeated measurements were taken with ANTERION high-resolution swept-source optical coherence tomographer (SS-OCT) to measure: corneal thickness (central and at 2, 4 and 6-mm diameters), aqueous depth (AD), lens thickness (LT), anterior chamber volume (ACV), axial length (AL), and pupil (diameter and position). The intrasubject standard deviation (Sw), coefficient of repeatability (CoR) and intraclass correlation coefficient (ICC) were calculated. Bland-Altman method was applied to analyze the difference between the first and the last measurement. The average and the difference between both measurements were calculated for all parameters. RESULTS: We have not found statistically significant differences between repeated measurements (p > 0.05). The mean difference for corneal thickness was between -0.08 and 0.28 µm. For AD and LT was 0.004 and -0.004 µm, respectively. ACV mean difference was -0.03 mm3 and for AL was 0.001 mm. Pupil diameter and position mean differences ranged between -0.008 and 0.009 mm. Overall, most ocular parameters had a Sw <1 and a CoR <2 in their respective units, and an ICC >0.92. CONCLUSIONS: The ANTERION high-resolution SS-OCT device provides good repeatability for different ocular biometric measurements.


Assuntos
Biometria/instrumentação , Olho/anatomia & histologia , Tomografia de Coerência Óptica/instrumentação , Adulto , Idoso , Câmara Anterior/anatomia & histologia , Feminino , Humanos , Cristalino/anatomia & histologia , Masculino , Pessoa de Meia-Idade , Pupila/fisiologia , Reprodutibilidade dos Testes , Adulto Jovem
8.
PLoS One ; 15(5): e0231983, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32407322

RESUMO

AIM: The aim of this study was to quantify gender-specific facial characteristics in younger and older adults and to determine how aging and body characteristics, such as height and body-mass index (BMI), influence facial sexual dimorphism. METHODS: The cohort study included 90 younger adults of Caucasian origin (average age of 45 females 23.2 ± 1.9 and 45 males 23.7 ± 2.4 years) and 90 older adults (average age of 49 females 78.1 ± 8.1 and 41 males 74.5 ± 7.7 years). Three-dimensional facial scans were performed with an Artec MHT 3D scanner. The data were analyzed using the software package Rapidform®. The parameters to evaluate facial symmetry, height, width, profile, facial shape, nose, eyes and mouth characteristics were determined based on 39 facial landmarks. Student's t-test was used to calculate the statistical differences between the genders in the younger and older adults and a multiple-linear-regression analysis was used to evaluate the impact of gender, age, body-mass index and body height. RESULTS: We found that the female faces were more symmetrical than the male faces, and this was statistically significant in the older adults. The female facial shape was more rounded and their faces were smaller, after normalizing for body size. The males had wider mouths, longer upper lips, larger noses and more prominent lower foreheads. Surprisingly, we found that all the gender-dependent characteristics were even more pronounced in the older adults. Increased facial asymmetry, decreased facial convexity, increased forehead angle, narrower vermilions and longer inter-eye distances occurred in both genders during aging. An increased BMI was associated with wider faces, more concave facial profiles and wider noses, while greater body height correlated with increased facial heights and wider mouths. CONCLUSION: Facial sexual dimorphism was confirmed by multiple parameters in our study, while the differences between the genders were more pronounced in the older adults.


Assuntos
Face/anatomia & histologia , Caracteres Sexuais , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Estudos de Coortes , Grupo com Ancestrais do Continente Europeu , Olho/anatomia & histologia , Feminino , Humanos , Imageamento Tridimensional , Masculino , Boca/anatomia & histologia , Nariz/anatomia & histologia , Adulto Jovem
9.
PLoS Genet ; 16(4): e1008583, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32236127

RESUMO

The precise control of eye size is essential for normal vision. TMEM98 is a highly conserved and widely expressed gene which appears to be involved in eye size regulation. Mutations in human TMEM98 are found in patients with nanophthalmos (very small eyes) and variants near the gene are associated in population studies with myopia and increased eye size. As complete loss of function mutations in mouse Tmem98 result in perinatal lethality, we produced mice deficient for Tmem98 in the retinal pigment epithelium (RPE), where Tmem98 is highly expressed. These mice have greatly enlarged eyes that are very fragile with very thin retinas, compressed choroid and thin sclera. To gain insight into the mechanism of action we used a proximity labelling approach to discover interacting proteins and identified MYRF as an interacting partner. Mutations of MYRF are also associated with nanophthalmos. The protein is an endoplasmic reticulum-tethered transcription factor which undergoes autoproteolytic cleavage to liberate the N-terminal part which then translocates to the nucleus where it acts as a transcription factor. We find that TMEM98 inhibits the self-cleavage of MYRF, in a novel regulatory mechanism. In RPE lacking TMEM98, MYRF is ectopically activated and abnormally localised to the nuclei. Our findings highlight the importance of the interplay between TMEM98 and MYRF in determining the size of the eye.


Assuntos
Olho/anatomia & histologia , Olho/metabolismo , Proteínas de Membrana/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Animais , Eletrorretinografia , Anormalidades do Olho/genética , Feminino , Deleção de Genes , Mutação com Perda de Função , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Tamanho do Órgão/genética , Ligação Proteica , Transporte Proteico , Epitélio Pigmentado da Retina/anormalidades , Epitélio Pigmentado da Retina/metabolismo , Retinaldeído/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
10.
J Craniofac Surg ; 31(4): 1034-1036, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32118666

RESUMO

OBJECTIVE: To evaluate the static eye characteristics of female patients with short, normal, and long faces. METHODS: Standardized full face frontal photographs of 163 female patients in the age range of 15 to 25 years were screened to evaluate their facial index (FI). Based on FI, 27 were short face (group I), 31 were normal face (group II), and 26 were long face (group III) photographs. All 84 photographs were then analyzed manually to determine various static eye characteristics. Descriptive statistics, 1-way analysis of variance and posthoc test (Bonferroni) for multiple comparisons were used. A P-value of 0.05 was considered as level of significance. RESULTS: The eye index was significantly different in group I, group II, and group III patients (P < 0.001). The position of the eyes in relation to width of face was significantly less in short (P < 0.05) faces and more in long (P < 0.001) faces compared to normal faces. The intereye distance was equal to the length of 1 eye in all 3 types of faces. Among all types of faces, the intereye distance was nearly half of the interpupillary distance and approximately one-fourth of the face width. The eye divergence was significantly less in long faces compared to short (P < 0.001) and normal faces (P < 0.05). CONCLUSION: The static morphologic characteristics of eyes were significantly different among females with different facial morphologies.


Assuntos
Olho/anatomia & histologia , Face/anatomia & histologia , Adolescente , Adulto , Biometria , Feminino , Humanos , Estrabismo , Adulto Jovem
11.
J Morphol ; 281(4-5): 465-475, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32092182

RESUMO

During the early ontogeny of fish larvae, the accurate development of the visual system plays a key role, because it is involved in locating food, orientation, selection of favorable habitat, and evasion of predators. The structure of the eye of the fish is typical of vertebrates, with some modifications related to the aquatic environment. In the present work, we describe the development of the larval eye of Engraulis anchoita for the first time. Larvae were collected at the Permanent Station of Environmental Studies (EPEA) in coastal waters of the Southwestern Atlantic Ocean during research cruises in 2015 and 2016. We describe the histology of the retina layers, determine the beginning of the functionality of the eye, and discuss a possible synchronization with the development of the digestive tract. This study provides information about the biology of E. anchoita, the most abundant fish species in the southwestern Atlantic Ocean. Also, recent studies have shown responses of the retina and other tissues to the increase in environmental acidity. Therefore, results of this study are also discussed with respect to the possible effect of acidification on the larvae of this species. The continuity of the time series developed at the EPEA will allow monitoring the effect of long-term environmental and biological variables on the early ontogeny of anchovy in the context of climate change. The high commercial fishing potential of E. anchoita due to its high abundance, as well as its essential role in the trophic web of other commercially valuable fishing resources of Argentina, reinforce the need to continue deepening knowledge about this species. Research highlights: Eyes of Engraulis anchoita larvae are functional from early larval stages. At hatching, the retina is formed by only few layers from which the other layers differentiates during ontogeny. Focal distance increases with larval growth.


Assuntos
Olho/anatomia & histologia , Olho/crescimento & desenvolvimento , Peixes/anatomia & histologia , Peixes/crescimento & desenvolvimento , Animais , Argentina , Ecossistema , Olho/citologia , Geografia , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Retina/anatomia & histologia , Retina/citologia , Retina/crescimento & desenvolvimento
12.
Philos Trans A Math Phys Eng Sci ; 378(2167): 20190442, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32008449

RESUMO

The optical systems mimicking the eye functions are of great importance in various applications including consumer electronics, medical equipment, machine vision systems and robotics. This optics offers advantages over traditional optical technologies such as the superior adaptation to changing conditions and the comprehensive range of functional characteristics at miniature sizes. This paper presents a review on the recent progress in the development of human eye-inspired optical systems. Liquid-based and elastomer-based tunable optical elements are discussed with the focus on the actuation mechanism, optical performance and the possibility of integration into artificial eye systems. This article is part of the theme issue 'Bioinspired materials and surfaces for green science and technology (part 3)'.


Assuntos
Materiais Biomiméticos , Biomimética/instrumentação , Olho/anatomia & histologia , Fenômenos Fisiológicos Oculares , Dispositivos Ópticos , Eletrônica , Desenho de Equipamento , Humanos , Robótica , Visão Ocular
13.
Plast Reconstr Surg ; 145(3): 514e-523e, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32097302

RESUMO

BACKGROUND: The three-dimensional surface imaging system is becoming more common in plastic surgeries. However, few studies have assessed three-dimensional periocular structures and surgical outcomes. This study aimed to propose a standardized three-dimensional anthropometric protocol for the periocular region, investigate its precision and accuracy, and determine the three-dimensional periocular anthropometric norms for young Caucasians. METHODS: Thirty-nine healthy young Caucasians (78 eyes) were enrolled. Three-dimensional facial images were obtained with a VECTRA M3 stereophotogrammetry device. Thirty-eight measurements in periocular regions were obtained from these images. Every subject underwent facial surface capture twice to evaluate its precision. A paper ruler was applied to assess its accuracy. RESULTS: Sixty-three percent of measurements in linear distances, curvatures, angles, and indices were found to reach a statistically significant difference between sexes (p ≤ 0.05, respectively). Across all measurements, the average mean absolute difference was 0.29 mm in linear dimensions, 0.56 mm in curvatures, 1.67 degrees in angles, and 0.02 in indices. In relative error of magnitude, 18 percent of the measurements were determined excellent, 51 percent very good, 31 percent good, and none moderate. The mean value of the paper-ruler scale was 10.01 ± 0.05 mm, the mean absolute difference value 0.02 mm, and the relative error of magnitude 0.17 percent. CONCLUSIONS: This is the first study to propose a detailed and standardized three-dimensional anthropometric protocol for the periocular region and confirm its high precision and accuracy. The results provided novel metric data concerning young Caucasian periocular anthropometry and determined the variability between sexes.


Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Antropometria/métodos , Olho/diagnóstico por imagem , Imageamento Tridimensional/métodos , Fotogrametria/métodos , Adulto , Antropometria/instrumentação , Estética , Grupo com Ancestrais do Continente Europeu , Olho/anatomia & histologia , Feminino , Humanos , Imageamento Tridimensional/normas , Masculino , Fotogrametria/instrumentação , Fotogrametria/normas , Reprodutibilidade dos Testes , Fatores Sexuais , Adulto Jovem
14.
Arch. Soc. Esp. Oftalmol ; 95(2): 84-89, feb. 2020. ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-195331

RESUMO

La dopamina es sintetizada por la tirosina hidroxilasa y es considerada como una catecolamina mayor en la retina de los vertebrados, incluyendo el pez cebra. Sin embargo, se conoce poco sobre la función del receptor de dopamina D2 (DRD2) en la fisiología retiniana. Por lo tanto, para dilucidar el papel del DRD2 en el desarrollo y la función de los ojos en el pez cebra, los peces fueron expuestos a la flufenazina, quinpirol, o la combinación de ambos, y luego se evaluó el tamaño del ojo, el diámetro del nervio óptico (ONd) y la adaptación visual al fondo. Los resultados mostraron que la flufenazina (flufenazina, antagonista DRD2) disminuyó el tamaño del ojo y el diámetro del nervio óptico seguido de una interrupción de la función visual. La adición de quinpirol (quinpirol, agonista DRD2) invirtió los efectos causados por flufenazina, lo que implica que DRD2 es necesario para el desarrollo y la función normal del ojo en el pez cebra. Considerando el papel de las neuronas dopaminérgicas en el desarrollo y la función de la retina, la disfunción de las vías de señalización de las neuronas dopaminérgicas en la retina puede causar anormalidades visuales, particularmente en la participación de la dopamina en la regulación de la respuesta de la luz


Dopamine is synthesized by tyrosine hydroxylase and is considered as a major catecholamine in the vertebrate retina, including zebrafish. However, little is known about the role of dopamine D2 receptor (DRD2) in retinal physiology. Therefore, to elucidate the role of DRD2 in the eye development and function in zebrafish, fish were exposed to fluphenazine, quinpirole, or combination of both. Subsequently, the eye size, optic nerve diameter (ONd), and visual background adaptation were evaluated. The results showed that fluphenazine (fluphenazine, DRD2 antagonist) decreased eye size and optic nerve diameter followed by disruption of visual function. The addition of Quinpirole (quinpirole, DRD2 agonist) reversed the effects caused by fluphenazine, implying that DRD2 is necessary for normal eye development and function in zebrafish. Considering the role of dopaminergic neurons in retinal development and function, dysfunction of dopaminergic neuron signaling pathways in the retina may cause visual abnormalities, particularly in the involvement of dopamine in regulating light response


Assuntos
Animais , Antagonistas dos Receptores de Dopamina D2/farmacologia , Olho/embriologia , Fenômenos Fisiológicos Oculares , Receptores de Dopamina D2/fisiologia , Olho/anatomia & histologia , Olho/crescimento & desenvolvimento , Flufenazina/farmacologia , Imuno-Histoquímica , Tamanho do Órgão , Quimpirol/farmacologia
15.
Integr Zool ; 15(4): 314-328, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31912651

RESUMO

In this study, the lateral line systems in Chinese cavefish eyeless Sinocyclocheilus tianlinensis and eyed Sinocyclocheilus macrophthalmus were investigated to reveal their morphological changes to survive in harsh environments. Compared with the eyed cavefish S. macrophthalmus (atypical), the lateral line system in the eyeless cavefish S. tianlinensis (typical) has certain features to adapt to the dark cave environments: the superficial lateral line system in the eyeless species possesses a higher number of superficial neuromasts and more hair cells within an individual neuromast, and the trunk lateral line canal system in S. tianlinensis exhibits larger canal pores, higher canal diameter and more pronounced constrictions. Fluid-structure interaction analysis suggested that the trunk lateral line canal system in the eyeless S. tianlinensis should be more sensitive than that in the eyed S. macrophthalmus. These morphological features of the lateral line system in the eyeless S. tianlinensis probably enhance the functioning of the lateral line system and compensate for the lack of eyes. The revelation of the form-function relationship in the cavefish lateral line system provides inspiration for the design of sensitive artificial flow sensors.


Assuntos
Cyprinidae/anatomia & histologia , Sistema da Linha Lateral/anatomia & histologia , Animais , Cavernas , Olho/anatomia & histologia , Sistema da Linha Lateral/ultraestrutura , Microscopia Eletrônica de Varredura/veterinária
16.
BMC Evol Biol ; 20(1): 4, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31914921

RESUMO

BACKGROUND: Early Cambrian Lagerstätten from China have greatly enriched our perspective on the early evolution of animals, particularly arthropods. However, recent studies have shown that many of these early fossil arthropods were more derived than previously thought, casting uncertainty on the ancestral euarthropod body plan. In addition, evidence from fossilized neural tissues conflicts with external morphology, in particular regarding the homology of the frontalmost appendage. RESULTS: Here we redescribe the multisegmented megacheirans Fortiforceps and Jianfengia and describe Sklerolibyon maomima gen. et sp. nov., which we place in Jianfengiidae, fam. nov. (in Megacheira, emended). We find that jianfengiids show high morphological diversity among megacheirans, both in trunk ornamentation and head anatomy, which encompasses from 2 to 4 post-frontal appendage pairs. These taxa are also characterized by elongate podomeres likely forming seven-segmented endopods, which were misinterpreted in their original descriptions. Plesiomorphic traits also clarify their connection with more ancestral taxa. The structure and position of the "great appendages" relative to likely sensory antero-medial protrusions, as well as the presence of optic peduncles and sclerites, point to an overall homology with the anterior head of radiodontans. This is confirmed by our Bayesian phylogeny, which places jianfengiids as the basalmost euarthropods, paraphyletic with other megacheirans, and in contiguity with isoxyids and radiodontans. CONCLUSIONS: Sklerolibyon and other jianfengiids expand the disparity of megacheirans and suggest that the common euarthropod ancestor possessed a remarkable phenotypic variability associated with the externalized cephalon, as well as endopods that were already heptopodomerous, which differs from previous hypotheses and observations. These animals also demonstrate that the frontalmost pair of arthrodized appendage is homologous between radiodontans and megacheirans, refuting the claim that the radiodontan frontal appendages evolved into the euarthropod labrum, and questioning its protocerebral identity. This evidence based on external anatomy now constitutes a solid benchmark upon which we should address issues of homology, with the help of carefully examined palaeoneurological data.


Assuntos
Artrópodes/anatomia & histologia , Fósseis , Animais , Artrópodes/classificação , Teorema de Bayes , Evolução Biológica , China , Extremidades/anatomia & histologia , Olho/anatomia & histologia , Cabeça/anatomia & histologia , Filogenia
17.
Arch Soc Esp Oftalmol ; 95(2): 84-89, 2020 Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31955999

RESUMO

Dopamine is synthesized by tyrosine hydroxylase and is considered as a major catecholamine in the vertebrate retina, including zebrafish. However, little is known about the role of dopamine D2 receptor (DRD2) in retinal physiology. Therefore, to elucidate the role of DRD2 in the eye development and function in zebrafish, fish were exposed to fluphenazine, quinpirole, or combination of both. Subsequently, the eye size, optic nerve diameter (ONd), and visual background adaptation were evaluated. The results showed that fluphenazine (fluphenazine, DRD2 antagonist) decreased eye size and optic nerve diameter followed by disruption of visual function. The addition of Quinpirole (quinpirole, DRD2 agonist) reversed the effects caused by fluphenazine, implying that DRD2 is necessary for normal eye development and function in zebrafish. Considering the role of dopaminergic neurons in retinal development and function, dysfunction of dopaminergic neuron signaling pathways in the retina may cause visual abnormalities, particularly in the involvement of dopamine in regulating light response.


Assuntos
Antagonistas dos Receptores de Dopamina D2/farmacologia , Olho/embriologia , Fenômenos Fisiológicos Oculares , Receptores de Dopamina D2/fisiologia , Animais , Olho/anatomia & histologia , Olho/crescimento & desenvolvimento , Flufenazina/farmacologia , Imuno-Histoquímica , Tamanho do Órgão , Quimpirol/farmacologia
18.
BMC Med Educ ; 20(1): 20, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31952526

RESUMO

BACKGROUND: Although neuroanatomy is considered an essential requirement in medical curriculum, its teaching has undergone many changes in recent years, with most medical schools starting to implement an integrated approach. The current paper describes the comparative evaluation of the neuroanatomy knowledge scores of medical students who attended two different pedagogic approaches of neuroanatomy in the Faculty of Medicine of the University of Porto. METHODS: Forty fourth-year medical students who attended a traditional stand-alone approach and 42 third-year medical students who attended an integrated approach completed a written test of knowledge. RESULTS: Although there were some significant differences, the results globally revealed no statistically significant difference between the neuroanatomy knowledge scores of the integrated and traditional education groups, with most students obtaining a passing score in both curricula. CONCLUSIONS: Our study is the first attempt to compare the knowledge acquired by medical students from two different pedagogical approaches to neuroanatomy. Although the integrated curricula were only implemented in the Faculty of Medicine of the University of Porto a few years ago, the students who attended these curricula obtained similar scores as those obtained by the students of the traditional curriculum. This finding suggests that an integrated curriculum can be, in light of curricular reform, an efficient approach to teaching neuroanatomy to medical students.


Assuntos
Currículo , Educação Médica/métodos , Neuroanatomia/educação , Estudantes de Medicina , Ensino , Anatomia/educação , Sistema Nervoso Central/anatomia & histologia , Orelha/anatomia & histologia , Avaliação Educacional/métodos , Olho/anatomia & histologia , Feminino , Humanos , Masculino , Fatores Sexuais
19.
Sci Rep ; 10(1): 1236, 2020 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988305

RESUMO

Animal colouration is often a trade-off between background matching for camouflage from predators, and conspicuousness for communication with con- or heterospecifics. Stomatopods are marine crustaceans known to use colour signals during courtship and contests, while their overall body colouration may provide camouflage. However, we have little understanding of how stomatopods perceive these signals in their environment or whether overall body coloration does provide camouflage from predators. Neogonodactylus oerstedii assess meral spot colour during contests, and meral spot colour varies depending on local habitat. By calculating quantum catch for N. oerstedii's 12 photoreceptors associated with chromatic vision, we found that variation in meral spot total reflectance does not function to increase signal contrast in the local habitat. Neogonodactylus oerstedii also show between-habitat variation in dorsal body colouration. We used visual models to predict a trichromatic fish predator's perception of these colour variations. Our results suggest that sandy and green stomatopods are camouflaged from a typical fish predator in rubble fields and seagrass beds, respectively. To our knowledge, this is the first study to investigate signal contrast and camouflage in a stomatopod. These results provide new insight into the function and evolution of colouration in a species with a complex visual system.


Assuntos
Mimetismo Biológico/fisiologia , Decápodes/fisiologia , Pigmentação/fisiologia , Animais , Percepção de Cores/fisiologia , Crustáceos , Decápodes/genética , Evolução Molecular , Olho/anatomia & histologia , Variação Genética , Células Fotorreceptoras/fisiologia , Filogenia , Pigmentos Biológicos/fisiologia
20.
Dev Sci ; 23(5): e12942, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31981278

RESUMO

Autism spectrum disorders (ASD) are associated with face perception atypicalities, and atypical experience with faces has been proposed as an underlying explanation. Studying the own-race advantage (ORA) for face recognition can reveal the effect of experience on face perception in ASD, although the small number of studies in the area present mixed findings. This study probed the ORA in ASD by comparing two cultural groups simultaneously for the first time. Children with ASD in the UK (N = 16) and Japan (N = 26) were compared with age- and ability-matched typically developing (TD) children in the UK (N = 16) and Japan (N = 26). Participants completed a two-alternative forced-choice task, whereby they had to recognize a just seen face from a foil which was manipulated in one of four ways (IC: identity change; EE: easy eyes; HE: hard eyes; HM: hard mouth). Face stimuli were Asian and Caucasian, and thus the same stimuli were own and other race depending on the cultural group. The ASD groups in the UK and Japan did not show impaired face recognition abilities, or impairments with recognizing faces depending on manipulations to the eye region, and importantly they showed an ORA. There was considerable heterogeneity in the presence of the ORA in ASD and TD and also across cultures. Children in Japan had higher accuracy than children in the UK, and TD children in Japan did not show an ORA. This cross-cultural study challenges the view that atypical experiences with faces lead to a reduced/absent ORA in ASD.


Assuntos
Transtorno Autístico/psicologia , Comparação Transcultural , Reconhecimento Facial/fisiologia , Grupo com Ancestrais do Continente Asiático , Criança , Olho/anatomia & histologia , Face/fisiologia , Feminino , Humanos , Japão , Masculino , Boca/anatomia & histologia , Reino Unido
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