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1.
Front Psychiatry ; 15: 1305691, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510801

RESUMO

Introduction: After an acute infection with the corona virus 10-20% of those affected suffer from ongoing or new symptoms. A causal therapy for the phenomenon known as Long/Post-COVID is still lacking and specific therapies addressing psychosocial needs of these patients are imperatively needed. The aim of the PsyLoCo-study is developing and piloting a psychotherapeutic manual, which addresses Long/Post-COVID-related psychosocial needs and supports in coping with persistent bodily symptoms as well as depressive or anxiety symptoms. Methods and analysis: This pilot trial implements a multi-centre, 2-arm (N=120; allocation ratio: 1:1), parallel group, randomised controlled design. The pilot trial is designed to test the feasibility and estimate the effect of 1) a 12-session psychotherapeutic intervention compared to 2) a wait-list control condition on psychosocial needs as well as bodily and affective symptoms in patients suffering from Long/Post-COVID. The intervention uses an integrative, manualized, psychotherapeutic approach. The primary study outcome is health-related quality of life. Outcome variables will be assessed at three timepoints, pre-intervention (t1), post-intervention (t2) and three months after completed intervention (t3). To determine the primary outcome, changes from t1 to t2 are examined. The analysis will be used for the planning of the RCT to test the efficacy of the developed intervention. Discussion: The pilot study will evaluate a 12-session treatment manual for Long/Post-COVID sufferers and the therapy components it contains. The analysis will provide insights into the extent to which psychotherapeutic treatment approaches improve the symptoms of Long/Post-COVID sufferers. The treatment manual is designed to be carried out by psychotherapists as well as people with basic training in psychotherapeutic techniques. This approach was chosen to enable a larger number of practitioners to provide therapeutic support for Long/Post-COVID patients. After completion of the pilot study, it is planned to follow up with a randomized controlled study and to develop a treatment guideline for general practitioners and interested specialists. Trial registration: The pilot trial has been registered with the German Clinical Trials Register (Deutsches Register Klinischer Studien; Trial-ID: DRKS00030866; URL: https://drks.de/search/de/trial/DRKS00030866) on March 7, 2023.

2.
J Exp Biol ; 227(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38149660

RESUMO

Early pioneering studies by Autrum on terrestrial arthropods first revealed that the visual systems of arthropods reflected their lifestyles and habitats. Subsequent studies have examined and confirmed Autrum's hypothesis that visual adaptions are driven by predator-prey interactions and activity cycles, with rapidly moving predatory diurnal species generally possessing better temporal resolution than slower moving nocturnal species. However, few studies have compared the vision between diurnal herbivores and nocturnal predators. In this study, the visual physiology of a nocturnal fast-moving predatory crab, the Atlantic ghost crab (Ocypode quadrata) and a diurnal herbivorous crab, the mangrove tree crab (Aratus pisonii), was examined. Spectral sensitivity, irradiance sensitivity and temporal resolution of the crabs were quantified using the electroretinogram (ERG), while the spatial resolution was calculated utilizing morphological methods. Both O. quadrata and A. pisonii had a single dark-adapted spectral sensitivity peak (494 and 499 nm, respectively) and chromatic adaptation had no effect on their spectral sensitivity, indicating that both species have monochromatic visual systems. The temporal resolution of O. quadrata was not significantly different from that of A. pisonii, but O. quadrata did possess a significantly greater spatial resolution and irradiance sensitivity. Both species possess an acute zone in the anterior region of their eyes. The data presented in this study will aid in the current understanding of the correlation between visual physiology and the life history of the animal.


Assuntos
Braquiúros , Animais , Braquiúros/fisiologia , Ecossistema , Olho , Eletrorretinografia , Fenômenos Fisiológicos Oculares
3.
Sci Rep ; 13(1): 16113, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752240

RESUMO

Many marine species can regulate the intensity of bioluminescence from their ventral photophores in order to counterilluminate, a camouflage technique whereby animals closely match the intensity of the downwelling illumination blocked by their bodies, thereby hiding their silhouettes. Recent studies on autogenic cuticular photophores in deep-sea shrimps indicate that the photophores themselves are light sensitive. Here, our results suggest photosensitivity in a second type of autogenic photophore, the internal organs of Pesta, found in deep-sea sergestid shrimps. Experiments were conducted onboard ship on live specimens, exposing the animals to bright light, which resulted in ultrastructural changes that matched those seen in crustacean eyes during the photoreceptor membrane turnover, a process that is crucial for the proper functioning of photosensitive components. In addition, RNA-seq studies demonstrated the expression of visual opsins and phototransduction genes in photophore tissue that are known to play a role in light detection, and electrophysiological measurements indicated that the light organs are responding to light received by the eyes. The long sought after mechanism of counterillumination remains unknown, but evidence of photosensitivity in photophores may indicate a dual functionality of light detection and emission.


Assuntos
Decápodes , Dermatite Fototóxica , Animais , Crustáceos , Eletrofisiologia Cardíaca , Olho
4.
Front Psychol ; 14: 1100236, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37333585

RESUMO

Patients with cancer might be particularly prone to stress caused by the COVID-19 pandemic. The aim of this study was to investigate the impact of pandemic-related stressors on oncological patients' psychological well-being. During the second wave of the COVID-19 pandemic in Germany 122 cancer out-patients of the Comprehensive Cancer Center Munich reported on COVID-19-related stressors (information satisfaction, threat perception, and fear of disease deterioration) and answered standardized questionnaires for psychosocial distress (DT) as well as depression and anxiety symptoms (PHQ-2, GAD-2). Multiple linear regression analyses were used to identify associations of the COVID-19-related stressors with psychological symptoms, controlling for sociodemographic, psychological (self-efficacy, ASKU) and clinical (somatic symptom burden, SSS-8) variables. Initially, satisfaction with information was significantly negatively associated with all three outcome variables. Fear of disease deterioration was associated with distress and depressive symptoms. After controlling for additional variables, only satisfaction with information remained an independent determinant of anxiety (ß = -0.35, p < 0.001). All three outcomes were most strongly determined by somatic symptom burden (ß ≥ 0.40, p < 0.001). The results of this study tentatively suggest that physical well-being overrides the relevance of some COVID-19-related stressors for oncological patients' psychological wellbeing. Physical symptoms are strongly tied to personal wellbeing as they are associated with suffering from cancer, which might be more central to personal wellbeing than the possibility of getting infected with SARS-CoV-2. However, satisfaction with the information received seems to be important beyond physical wellbeing, as this emerged as an independent determinant of anxiety.

5.
Dtsch Med Wochenschr ; 147(10): 41-49, 2022 04.
Artigo em Alemão | MEDLINE | ID: mdl-35545063

RESUMO

BACKGROUND: This study investigates current needs and psychosocial burden of out-patients with cancer during the COVID-19-Pandemic. MATERIAL AND METHODS: Between 11/2020 and 02/2021 122 cancer patients who underwent out-patient treatment at the Comprehensive Cancer Center Munich participated in the study. Based on a standardized, semi-structured interview, participants were asked about their knowledge and informational needs related to COVID-19, risk perception and concerns regarding continuing out-patient treatment, COVID-19 related distress, confidence in the national health system, and their readiness to get vaccinated against COVID-19. Additionally, patients filled out the distress thermometer (DT). RESULTS: More than a third of the patients (34,2 %, n = 41/120) wanted to receive more information about the effects of the coronavirus on their cancer and their treatment. 17,2 % (n = 21/122) had faced changes concerning their current or planned treatment. 42/121 (34,7 %) of the patients were clinically distressed (DT ≥ 5). A possible overload of the health care system was the most commonly reported COVID-related concern (77,9 %, n = 95/122), followed by being concerned that their family members might be additionally worried about them (56,2 %, n = 68/121). 71,2 % (n = 74/104) of the patients are willing to be vaccinated; 60 % (n = 18/30) of those undecided or refusing at the time of the survey expressed a desire to have a consultation with an oncologist before giving their final consent to vaccination. DISCUSSION: Corona-specific distress of cancer patients relates in particular to the course of therapy, but also to a possible overload of the health care system. Oncology care teams should allow space for questions from their patients, acknowledge possible uncertainties, provide emotional support, and draw attention to reliable sources of information.


Assuntos
COVID-19 , Neoplasias , COVID-19/epidemiologia , Humanos , Neoplasias/epidemiologia , Neoplasias/terapia , Pacientes Ambulatoriais , Pandemias/prevenção & controle , SARS-CoV-2
7.
Vaccines (Basel) ; 10(5)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35632445

RESUMO

(1) Background: Health care workers (HCWs) play a key role in increasing anti-COVID vaccination rates. Fear of potential side effects is one of the main reasons for vaccine hesitancy. We investigated which side effects are of concern to HCWs and how these are associated with vaccine hesitancy. (2) Methods: Data were collected in an online survey in February 2021 among HCWs from across Germany with 4500 included participants. Free-text comments on previously experienced vaccination side effects, and fear of short- and long-term side effects of the COVID-19 vaccination were categorized and analyzed. (3) Results: Most feared short-term side effects were vaccination reactions, allergic reactions, and limitations in daily life. Most feared long-term side effects were (auto-) immune reactions, neurological side effects, and currently unknown long-term consequences. Concerns about serious vaccination side effects were associated with vaccination refusal. There was a clear association between refusal of COVID-19 vaccination in one's personal environment and fear of side effects. (4) Conclusions: Transparent information about vaccine side effects is needed, especially for HCW. Especially when the participants' acquaintances advised against vaccination, they were significantly more likely to fear side effects. Thus, further education of HCW is necessary to achieve good information transfer in clusters as well.

8.
Psychooncology ; 31(5): 770-778, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34894364

RESUMO

OBJECTIVE: To improve allocation of psychosocial care and to provide patient-oriented support offers, identification of determinants of elevated distress is needed. So far, there is a lack of evidence investigating the interplay between individual disposition and current clinical and psychosocial determinants of distress in the inpatient setting. METHODS: In this cross-sectional study, we investigated 879 inpatients with different cancer sites treated in a German Comprehensive Cancer Center. Assessment of determinants of elevated distress included sociodemographic, clinical and psychosocial characteristics as well as dimensions of personality. Multiple linear regression was applied to identify determinants of psychosocial distress. RESULTS: Mean age of the patients was M = 61.9 (SD = 11.8), 48.1% were women. In the multiple linear regression model younger age (ß = -0.061, p = 0.033), higher neuroticism (ß = 0.178, p = <0.001), having metastases (ß = 0.091, p = 0.002), being in a worse physical condition (ß = 0.380, p = <0.001), depressive symptoms (ß = 0.270, p = <0.001), not feeling well informed about psychological support (ß = 0.054, p = 0.046) and previous uptake of psychological treatment (ß = 0.067, p = 0.020) showed significant associations with higher psychosocial distress. The adjusted R2 of the overall model was 0.464. CONCLUSION: Controlling for sociodemographic characteristics and dispositional vulnerability, that is neuroticism, current clinical and psychosocial characteristics were still associated with hospitalized patients' psychosocial distress. Psycho-oncologists should address both, the more transient emotional responses, such as depressive symptoms, as well as more enduring patient characteristics, like neuroticism.


Assuntos
Neoplasias , Estudos Transversais , Feminino , Humanos , Pacientes Internados/psicologia , Masculino , Neoplasias/psicologia , Neuroticismo , Personalidade , Estresse Psicológico/psicologia
9.
Vaccines (Basel) ; 9(7)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34358193

RESUMO

Vaccination hesitancy is a threat to herd immunity. Healthcare workers (HCWs) play a key role in promoting Coronavirus disease 2019 (COVID-19) vaccination in the general population. We therefore aimed to provide data on COVID-19 vaccination acceptance/hesitancy among German HCWs. For this exploratory, cross-sectional study, an online survey was conducted in February 2021. The survey included 54 items on demographics; previous vaccination behavior; trust in vaccines, physicians, the pharmaceutical industry and health politics; fear of adverse effects; assumptions regarding the consequences of COVID-19; knowledge about vaccines; and information seeking behavior. Odds ratios with 95% confidence intervals were calculated and chi-square tests were performed. Four thousand five hundred surveys were analyzed. The overall vaccination acceptance was 91.7%. The age group ≤20 years showed the lowest vaccination acceptance. Factors associated with vaccination hesitancy were lack of trust in authorities and pharmaceutical companies. Attitudes among acquaintances were associated with vaccination hesitancy too. Participants with vaccination hesitancy more often obtained information about COVID-19 vaccines via messenger services or online video platforms and underperformed in the knowledge test. We found high acceptance amongst German HCWs. Several factors associated with vaccination hesitancy were identified which could be targeted in HCW vaccination campaigns.

10.
Environ Sci Pollut Res Int ; 27(36): 45270-45281, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32789631

RESUMO

Deep-water column micronekton play a key role in oceanic food webs and represent an important trophic link between deep- and shallow-water ecosystems. Thus, the potential impacts of sub-surface hydrocarbon plumes on these organisms are critical to developing a more complete understanding of ocean-wide effects resulting from deep-sea oil spills. This work was designed to advance the understanding of hydrocarbon toxicity in several ecologically important deep-sea micronekton species using controlled laboratory exposures aimed at determining lethal threshold exposure levels. The current study confirmed the results previously determined for five deep-sea micronekton by measuring lethal threshold levels for phenanthrene between 81.2 and 277.5 µg/L. These results were used to calibrate the target lipid model and to calculate a critical target lipid body burden for each species. In addition, an oil solubility model was used to predict the acute toxicity of MC252 crude oil to vertically migrating crustaceans, Janicella spinacauda and Euphausiidae spp., and to compare the predictions with results of a 48-h constant exposure toxicity test with passive-dosing. Results confirmed that the tested deep-sea micronekton appear more sensitive than many other organisms when exposed to dissolved oil, but baseline stress complicated interpretation of results.


Assuntos
Poluição por Petróleo , Petróleo , Fenantrenos , Poluentes Químicos da Água , Animais , Ecossistema , Oceanos e Mares , Petróleo/análise , Petróleo/toxicidade , Poluição por Petróleo/análise , Fenantrenos/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
11.
Sci Rep ; 10(1): 8376, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32409729

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

12.
Sci Rep ; 10(1): 4485, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32161283

RESUMO

Extraocular photoreception, the ability to detect and respond to light outside of the eye, has not been previously described in deep-sea invertebrates. Here, we investigate photosensitivity in the bioluminescent light organs (photophores) of deep-sea shrimp, an autogenic system in which the organism possesses the substrates and enzymes to produce light. Through the integration of transcriptomics, in situ hybridization and immunohistochemistry we find evidence for the expression of opsins and phototransduction genes known to play a role in light detection in most animals. Subsequent shipboard light exposure experiments showed ultrastructural changes in the photophore similar to those seen in crustacean eyes, providing further evidence that photophores are light sensitive. In many deep-sea species, it has long been documented that photophores emit light to aid in counterillumination - a dynamic form of camouflage that requires adjusting the organ's light intensity to "hide" their silhouettes from predators below. However, it remains a mystery how animals fine-tune their photophore luminescence to match the intensity of downwelling light. Photophore photosensitivity allows us to reconsider the organ's role in counterillumination - not only in light emission but also light detection and regulation.

13.
Environ Toxicol Chem ; 36(12): 3415-3423, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28731272

RESUMO

There are few studies that have evaluated hydrocarbon toxicity to vertically migrating deep-sea micronekton. Crustaceans were collected alive using a 9-m2 Tucker trawl with a thermally insulated cod end and returned to the laboratory in 10 °C seawater. Toxicity of the polycyclic aromatic hydrocarbon 1-methylnaphthalene to Americamysis bahia, Janicella spinacauda, Systellaspis debilis, Sergestes sp., Sergia sp., and a euphausiid species was assessed in a constant exposure toxicity test utilizing a novel passive dosing toxicity testing protocol. The endpoint of the median lethal concentration tests was mortality, and the results revealed high sensitivity of the deep-sea micronekton compared with other species for which these data are available. Threshold concentrations were also used to calculate critical target lipid body burdens using the target lipid model. Environ Toxicol Chem 2017;36:3415-3423. © 2017 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.


Assuntos
Crustáceos/efeitos dos fármacos , Naftalenos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Brasil , Crustáceos/química , Gotículas Lipídicas/química , Água do Mar , Testes de Toxicidade
14.
Philos Trans R Soc Lond B Biol Sci ; 372(1717)2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28193816

RESUMO

For all visually competent organisms, the driving force behind the adaptation of photoreceptors involves obtaining the best balance of resolution to sensitivity in the prevailing light regime, as an increase in sensitivity often results in a decrease in resolution. A number of marine species have an additional problem to deal with, in that the juvenile stages live in relatively brightly lit shallow (100-200 m depth) waters, whereas the adult stages have daytime depths of more than 600 m, where little downwelling light remains. Here, I present the results of electrophysiological analyses of the temporal resolution and irradiance sensitivity of juvenile and adult stages of two species of ontogenetically migrating crustaceans (Gnathophausia ingens and Systellaspis debilis) that must deal with dramatically different light environments and temperatures during their life histories. The results demonstrate that there are significant effects of temperature on temporal resolution, which help to optimize the visual systems of the two life-history stages for their respective light environments.This article is part of the themed issue 'Vision in dim light'.


Assuntos
Crustáceos/fisiologia , Meio Ambiente , Visão Ocular , Adaptação Fisiológica , Animais , Crustáceos/crescimento & desenvolvimento , Escuridão , Características de História de Vida , Luz
15.
Infect Genet Evol ; 43: 371-7, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27275846

RESUMO

Walnut blight caused by Xanthomonas arboricola pv. juglandis (Xaj) is one of the most frequent infective diseases of walnut, resulting in serious economic losses. One potential solution to control this disease could be the application of bacteriophages. In this study, 24 phages were isolated from soil and walnut aerial tissues infected with Xaj. Two polyvalent bacteriophages, Xaj2 and Xaj24 were chosen for further characterization including their morphological, physiological and genomic analyses. Xaj2 was classified as Siphoviridae whereas Xaj24 belonged to the Podoviridae family. Both phages demonstrated lytic effect on Xaj in laboratory trials. Complete genomes of Xaj2 and Xaj24 were determined. Genomes of Xaj2 and Xaj24 consisted of 49.241 and 44.861 nucleotides encoding 80 and 53 genes, respectively. Comparative genome analyses have revealed that Xaj2 had a unique genome sequence, while Xaj24 was a phiKMV-like phage and it was most similar to the Prado phage which is virulent for Xylella fastidiosa and Xanthomonas spp. In this study, we present the first two complete Xaj phage sequences enabling an insight into the genomics of Xaj phages.


Assuntos
Genoma Viral , Filogenia , Podoviridae/genética , Siphoviridae/genética , Microbiologia do Solo , Xanthomonas/virologia , Agentes de Controle Biológico , DNA Viral/genética , Sequenciamento de Nucleotídeos em Larga Escala , Juglans/microbiologia , Lisogenia/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Podoviridae/classificação , Podoviridae/isolamento & purificação , Podoviridae/patogenicidade , Siphoviridae/classificação , Siphoviridae/isolamento & purificação , Siphoviridae/patogenicidade , Xanthomonas/crescimento & desenvolvimento , Xanthomonas/patogenicidade
16.
J Exp Biol ; 219(Pt 4): 597-608, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26747903

RESUMO

Cleaner shrimp (Decapoda) regularly interact with conspecifics and client reef fish, both of which appear colourful and finely patterned to human observers. However, whether cleaner shrimp can perceive the colour patterns of conspecifics and clients is unknown, because cleaner shrimp visual capabilities are unstudied. We quantified spectral sensitivity and temporal resolution using electroretinography (ERG), and spatial resolution using both morphological (inter-ommatidial angle) and behavioural (optomotor) methods in three cleaner shrimp species: Lysmata amboinensis, Ancylomenes pedersoni and Urocaridella antonbruunii. In all three species, we found strong evidence for only a single spectral sensitivity peak of (mean ± s.e.m.) 518 ± 5, 518 ± 2 and 533 ± 3 nm, respectively. Temporal resolution in dark-adapted eyes was 39 ± 1.3, 36 ± 0.6 and 34 ± 1.3 Hz. Spatial resolution was 9.9 ± 0.3, 8.3 ± 0.1 and 11 ± 0.5 deg, respectively, which is low compared with other compound eyes of similar size. Assuming monochromacy, we present approximations of cleaner shrimp perception of both conspecifics and clients, and show that cleaner shrimp visual capabilities are sufficient to detect the outlines of large stimuli, but not to detect the colour patterns of conspecifics or clients, even over short distances. Thus, conspecific viewers have probably not played a role in the evolution of cleaner shrimp appearance; rather, further studies should investigate whether cleaner shrimp colour patterns have evolved to be viewed by client reef fish, many of which possess tri- and tetra-chromatic colour vision and relatively high spatial acuity.


Assuntos
Palaemonidae/fisiologia , Animais , Cor , Visão de Cores , Eletrorretinografia , Peixes , Luz , Fenômenos Fisiológicos Oculares , Percepção Espacial/fisiologia , Especificidade da Espécie , Acuidade Visual
17.
Mol Phylogenet Evol ; 83: 278-92, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25482362

RESUMO

Bioluminescence is essential to the survival of many organisms, particularly in the deep sea where light is limited. Shrimp of the family Oplophoridae exhibit a remarkable mechanism of bioluminescence in the form of a secretion used for predatory defense. Three of the ten genera possess an additional mode of bioluminescence in the form of light-emitting organs called photophores. Phylogenetic analyses can be useful for tracing the evolution of bioluminescence, however, the few studies that have attempted to reconcile the relationships within Oplophoridae have generated trees with low-resolution. We present the most comprehensive phylogeny of Oplophoridae to date, with 90% genera coverage using seven genes (mitochondrial and nuclear) across 30 oplophorid species. We use our resulting topology to trace the evolution of bioluminescence within Oplophoridae. Previous studies have suggested that oplophorid visual systems may be tuned to differentiate the separate modes of bioluminescence. While all oplophorid shrimp possess a visual pigment sensitive to blue-green light, only those bearing photophores have an additional pigment sensitive to near-ultraviolet light. We attempt to characterize opsins, visual pigment proteins essential to light detection, in two photophore-bearing species (Systellaspis debilis and Oplophorus gracilirostris) and make inferences regarding their function and evolutionary significance.


Assuntos
Evolução Biológica , Decápodes/classificação , Luminescência , Opsinas/genética , Filogenia , Animais , Teorema de Bayes , Decápodes/genética , Luz , Funções Verossimilhança , Análise de Sequência de DNA , Transcriptoma , Raios Ultravioleta
18.
Artigo em Inglês | MEDLINE | ID: mdl-24078200

RESUMO

The potential for color vision in elasmobranchs has been studied in detail; however, a high degree of variation exists among the group. Evidence for ultraviolet (UV) vision is lacking, despite the presence of UV vision in every other vertebrate class. An integrative physiological approach was used to investigate color and ultraviolet vision in cownose rays and yellow stingrays, two batoids that inhabit different spectral environments. Both species had peaks in UV, short, medium, and long wavelength spectral regions in dark-, light-, and chromatic-adapted electroretinograms. Although no UV cones were found with microspectrophotometric analysis, both rays had multiple cone visual pigments with λ max at 470 and 551 nm in cownose rays (Rhinoptera bonasus) and 475, 533, and 562 nm in yellow stingrays (Urobatis jamaicensis). The same analysis demonstrated that both species had rod λ max at 500 and 499 nm, respectively. The lens and cornea of cownose rays maximally transmitted wavelengths greater than 350 nm and greater than 376 nm in yellow stingrays. These results support the potential for color vision in these species and future investigations should reveal the extent to which color discrimination is significant in a behavioral context.


Assuntos
Visão de Cores/fisiologia , Rajidae/fisiologia , Animais , Ecologia , Eletrorretinografia , Células Fotorreceptoras Retinianas Cones/fisiologia , Pigmentos da Retina/fisiologia , Células Fotorreceptoras Retinianas Bastonetes/fisiologia , Pigmentação da Pele , Especificidade da Espécie , Espectrofotometria , Raios Ultravioleta
19.
Physiol Biochem Zool ; 86(3): 285-97, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23629879

RESUMO

Visual temporal resolution and spectral sensitivity of three coastal teleost species (common snook [Centropomus undecimalis], gray snapper [Lutjanus griseus], and pinfish [Lagodon rhomboides]) were investigated by electroretinogram. Temporal resolution was quantified under photopic and scotopic conditions using response waveform dynamics and maximum critical flicker fusion frequency (CFFmax). Photopic CFFmax was significantly higher than scotopic CFFmax in all species. The snapper had the shortest photoreceptor response latency time (26.7 ms) and the highest CFFmax (47 Hz), suggesting that its eyes are adapted for a brighter photic environment. In contrast, the snook had the longest response latency time (36.8 ms) and lowest CFFmax (40 Hz), indicating that its eyes are adapted for a dimmer environment or nocturnal lifestyle. Species spectral responses ranged from 360 to 620 nm and revealed the presence of rods sensitive to dim and twilight conditions, as well as multiple cone visual pigments providing the basis for color and contrast discrimination. Collectively, our results demonstrate differences in visual function among species inhabiting the Indian River Lagoon system, representative of their unique ecology and life histories.


Assuntos
Ecossistema , Peixes/fisiologia , Visão Ocular , Animais , Eletrorretinografia , Estuários , Florida , Cadeia Alimentar , Luz , Comportamento Predatório , Tempo de Reação , Células Fotorreceptoras Retinianas Cones/fisiologia , Pigmentos da Retina/fisiologia , Células Fotorreceptoras Retinianas Bastonetes/fisiologia , Especificidade da Espécie , Fatores de Tempo
20.
J Exp Biol ; 215(Pt 19): 3335-43, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22956246

RESUMO

Bioluminescence is common and well studied in mesopelagic species. However, the extent of bioluminescence in benthic sites of similar depths is far less studied, although the relatively large eyes of benthic fish, crustaceans and cephalopods at bathyal depths suggest the presence of significant biogenic light. Using the Johnson-Sea-Link submersible, we collected numerous species of cnidarians, echinoderms, crustaceans, cephalopods and sponges, as well as one annelid from three sites in the northern Bahamas (500-1000 m depth). Using mechanical and chemical stimulation, we tested the collected species for light emission, and photographed and measured the spectra of the emitted light. In addition, in situ intensified video and still photos were taken of different benthic habitats. Surprisingly, bioluminescence in benthic animals at these sites was far less common than in mesopelagic animals from similar depths, with less than 20% of the collected species emitting light. Bioluminescent taxa comprised two species of anemone (Actinaria), a new genus and species of flabellate Parazoanthidae (formerly Gerardia sp.) (Zoanthidea), three sea pens (Pennatulacea), three bamboo corals (Alcyonacea), the chrysogorgiid coral Chrysogorgia desbonni (Alcyonacea), the caridean shrimp Parapandalus sp. and Heterocarpus ensifer (Decapoda), two holothuroids (Elasipodida and Aspidochirota) and the ophiuroid Ophiochiton ternispinus (Ophiurida). Except for the ophiuroid and the two shrimp, which emitted blue light (peak wavelengths 470 and 455 nm), all the species produced greener light than that measured in most mesopelagic taxa, with the emissions of the pennatulaceans being strongly shifted towards longer wavelengths. In situ observations suggested that bioluminescence associated with these sites was due primarily to light emitted by bioluminescent planktonic species as they struck filter feeders that extended into the water column.


Assuntos
Ecossistema , Luz , Medições Luminescentes , Oceanos e Mares , Visão Ocular/efeitos da radiação , Animais , Bahamas , Especificidade da Espécie , Manejo de Espécimes , Espectrometria de Fluorescência , Gravação em Vídeo
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