Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Conserv Biol ; 37(5): e14110, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37144486

RESUMO

Fisheries bycatch is a critical threat to sea turtle populations worldwide, particularly because turtles are vulnerable to multiple gear types. The Canary Current is an intensely fished region, yet there has been no demographic assessment integrating bycatch and population management information of the globally significant Cabo Verde loggerhead turtle (Caretta caretta) population. Using Boa Vista island (Eastern Cabo Verde) subpopulation data from capture-recapture and nest monitoring (2013-2019), we evaluated population viability and estimated regional bycatch rates (2016-2020) in longline, trawl, purse-seine, and artisanal fisheries. We further evaluated current nesting trends in the context of bycatch estimates, existing hatchery conservation measures, and environmental (net primary productivity) variability in turtle foraging grounds. We projected that current bycatch mortality rates would lead to the near extinction of the Boa Vista subpopulation. Bycatch reduction in longline fisheries and all fisheries combined would increase finite population growth rate by 1.76% and 1.95%, respectively. Hatchery conservation increased hatchling production and reduced extinction risk, but alone it could not achieve population growth. Short-term increases in nest counts (2013-2021), putatively driven by temporary increases in net primary productivity, may be masking ongoing long-term population declines. When fecundity was linked to net primary productivity, our hindcast models simultaneously predicted these opposing long-term and short-term trends. Consequently, our results showed conservation management must diversify from land-based management. The masking effect we found has broad-reaching implications for monitoring sea turtle populations worldwide, demonstrating the importance of directly estimating adult survival and that nest counts might inadequately reflect underlying population trends.


Impactos demográficos ocultos de la pesca y determinantes ambientales de la fecundidad en una población de tortugas marinas Resumen La captura accidental de las pesquerías es una amenaza importante para la población mundial de tortugas marinas pues estos reptiles son vulnerables a muchos tipos de artes de pesca. Aunque la Corriente de Canarias es una zona de pesca intensa, no se han realizado análisis demográficos que integren información de la captura accidental y el manejo poblacional de la tortuga caguama de Cabo Verde (Caretta caretta), una población de importancia mundial. Usamos datos de captura-recaptura y monitoreo de nidos (2013-2019) de la subpoblación de la isla Boa Vista (Cabo Verde occidental) para evaluar la viabilidad poblacional y además estimamos el volumen de captura accidental a nivel regional (2016-2020) de las pesquerías de palangre, arrastre, red de cerco y artesanal. También analizamos las tendencias de la anidación en el contexto de las estimas actuales de captura accidental, del posible impacto del traslado de las puestas a viveros y de la variabilidad ambiental (productividad primaria neta) en la zona donde se alimentan las tortugas. Proyectamos que, de persistir, la tasa actual de mortalidad por captura accidental llevaría a la subpoblación de Boa Vista al borde de la extinción. La reducción de la captura accidental en la flota de palangre incrementaría la tasa finita de crecimiento poblacional en un 1.76% y la reducción en todas las flotas un 1.95%. El traslado de las puestas a viveros incrementó la producción de crías y redujo el riesgo de extinción, pero no logra el crecimiento poblacional por sí solo. Los incrementos a corto plazo en el conteo de nidos (2013-2021), causados posiblemente por los incrementos temporales en la productividad primaria neta, pueden estar ocultando un declive poblacional. Cuando relacionamos la fecundidad con la productividad primaria neta, nuestros modelos retrospectivos pronosticaron correctamente ambas tendencias, a corto y largo plazo. Como consecuencia, nuestros resultados mostraron que la gestión de la conservación debe diversificarse más allá de las medidas aplicadas durante la fase terrestre. Los efectos ocultos que descubrimos tienen implicaciones generales para el monitoreo de las poblaciones de tortugas marinas en otras partes del mundo, lo que demuestra la importancia de la estimación directa de la supervivencia de adultos y que el conteo de nidos podría no refleja correctamente las tendencias poblacionales subyacentes.


Assuntos
Tartarugas , Animais , Conservação dos Recursos Naturais/métodos , Caça , Pesqueiros , Fertilidade , Demografia
2.
J Environ Manage ; 339: 117805, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37043912

RESUMO

As climate-related impacts threaten marine biodiversity globally, it is important to adjust conservation efforts to mitigate the effects of climate change. Translating scientific knowledge into practical management, however, is often complicated due to resource, economic and policy constraints, generating a knowledge-action gap. To develop potential solutions for marine turtle conservation, we explored the perceptions of key actors across 18 countries in the Mediterranean. These actors evaluated their perceived relative importance of 19 adaptation and mitigation measures that could safeguard marine turtles from climate change. Of importance, despite differences in expertise, experience and focal country, the perceptions of researchers and management practitioners largely converged with respect to prioritizing adaptation and mitigation measures. Climate change was considered to have the greatest impacts on offspring sex ratios and suitable nesting sites. The most viable adaptation/mitigation measures were considered to be reducing other pressures that act in parallel to climate change. Ecological effectiveness represented a key determinant for implementing proposed measures, followed by practical applicability, financial cost, and societal cost. This convergence in opinions across actors likely reflects long-standing initiatives in the Mediterranean region towards supporting knowledge exchange in marine turtle conservation. Our results provide important guidance on how to prioritize measures that incorporate climate change in decision-making processes related to the current and future management and protection of marine turtles at the ocean-basin scale, and could be used to guide decisions in other regions globally. Importantly, this study demonstrates a successful example of how interactive processes can be used to fill the knowledge-action gap between research and management.


Assuntos
Ecossistema , Tartarugas , Animais , Conservação dos Recursos Naturais/métodos , Mudança Climática , Biodiversidade
3.
J Sports Sci Med ; 17(4): 557-562, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30479523

RESUMO

The purpose of this study was to analyze heart rate variability (HRV) oscillations before and after a marathon which involved trans-meridian air travel and substantial time zone differences in a professional wheelchair athlete with Charcot-Marie-Tooth (CMT) disease. The natural logarithm of the root mean square difference between adjacent normal R-R intervals (Ln rMSSD) was measured daily on the days before, including and following the race. Relative to baseline, small (-3.8 - -4.6%) reductions in LnRMSSD were observed following relocation and on race-day, indicating only minor effects of travel on cardiac-autonomic activity. On the morning following the marathon, a 23.1% reduction in Ln rMSSD was observed, which returned to baseline by 48 h. The race time set by the athlete was the world-leading time in his class. This case study showed that Ln rMSSD responses to marathon in an elite wheelchair athlete with CMT was similar to those previously reported among unrestricted endurance athletes.


Assuntos
Desempenho Atlético , Frequência Cardíaca , Esportes para Pessoas com Deficiência , Cadeiras de Rodas , Adulto , Atletas , Doença de Charcot-Marie-Tooth , Ergometria , Humanos , Masculino , Viagem
4.
Dev Dyn ; 244(9): 1144-1157, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26088476

RESUMO

BACKGROUND: Amniote gastrulation is often described with respect to human, mouse and chick development by the presence of the primitive streak, a posterior-to-anterior midline morphological cell ingression feature that has come to define Amniote gastrulation. How this midline, ingression-based strategy of gastrulation evolved from the ancestral blastopore, a circumferential involution event in Anamniotes, is unknown. However, within the Amniote clade there exists a more diverse range of gastrulation strategies than just the primitive streak. Investigating gastrulation in a wider range of Amniotes provides a way to understand evolutionary transition from blastopore to the primitive streak. RESULTS: We analysed early to late gastrulation stages of Chamaeleo calyptratus, showing their unique morphology through confocal imaging of F-actin and laminin-stained embryos to visualise cell morphology and assess basal lamina integrity. We analysed the expression pattern of core mesodermal markers Brachyury and Fgf8 and complimented this analysis with that of the turtle, Trachemys scripta. CONCLUSIONS: Our analysis suggests that reptile gastrulation is bi-modal; primary internalization occurs anteriorly by means of an incomplete blastopore-like opening, while posteriorly the cells undergo ingression in the Brachyury-expressing blastoporal plate. This strategy stands mid-way between Anamniotes and Avians/Mammals, suggesting that blastoporal plate is a precursor of the avian primitive streak. Developmental Dynamics 244:1144-1157, 2015. © 2015 Wiley Periodicals, Inc.

5.
Arch Environ Contam Toxicol ; 69(1): 95-103, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25586169

RESUMO

Temporary ponds, where many amphibians from temperate regions breed, show an annual cycle with a maximum water volume in spring followed by a progressive desiccation throughout late spring and summer. This desiccation leads to a decrease in dissolved oxygen and an increase in nitrogen levels, which can additionally increase because of anthropogenic sources such as chemical fertilizers. We analyzed the toxicity posed by environmentally relevant levels of a common nitrogenous fertilizer, ammonium nitrate, at different conditions of oxygen availability to Bufo calamita tadpoles, which typically develop in ephemeral ponds. Ammonium nitrate (90.3 mg N-NO3NH4/l) and hypoxic conditions (initial dissolved oxygen 4.53 ± 0.40 mg/l) caused significant lethal effects after 7 and 12 days of exposure, respectively. At the end of experiment (16 days), mortality rates were 32.5 % in individuals exposed to the fertilizer and 15 % in those growing under hypoxic conditions. When both stressors were combined, they showed an additive effect on tadpole survival. Malformations, such as oedemas and spinal curvatures, and locomotory abnormalities, were detected after 12 days of experiment in >90 % of individuals exposed to 45.2 mg N-NO3NH4/l under hypoxic conditions, whereas none of these stressors by separate related to abnormality rates >35 %. Delayed development was also observed in tadpoles exposed to ammonium nitrate with hypoxia affecting developmental rate only after 12 days of exposure. The results are discussed in terms of potential mechanisms linking negative effects of both factors as well as in terms of potential alterations of the ecological plasticity that often allows amphibians to survive in unpredictable environments.


Assuntos
Larva/efeitos dos fármacos , Nitratos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bufonidae , Fertilizantes/toxicidade , Oxigênio/análise
6.
Rev Esp Enferm Dig ; 107(3): 178-81, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25733044

RESUMO

The effect of an individualized exercise programme on a non-alcoholic steatohepatitis case is presented. Before entering the programme the patient was treated with conventional recommendations on diet plus aerobic exercise during fourteen years, without major improvements of his analytical parameters.Two years after including him in a tailored exercise programme, aimed to fulfil the recommendations of the American College of Sports Medicine, his blood markers of liver dysfunction and cardiometabolic risk tended to improve. Consequently, our data support the idea that in non-alcoholic steatohepatitis the exercise-based therapeutic interventions should be individualized taking into account the cardio-respiratory and muscular fitness of the patient, rather than using generic behavioural recommendations.


Assuntos
Terapia por Exercício/métodos , Hepatopatia Gordurosa não Alcoólica/terapia , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Humanos , Masculino , Hepatopatia Gordurosa não Alcoólica/metabolismo , Medicina de Precisão , Resultado do Tratamento
7.
Environ Pollut ; 344: 123338, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38218543

RESUMO

Santa Luzia, an uninhabited island in the archipelago of Cabo Verde, serves as a natural laboratory and important nesting site for loggerhead turtles Carettacaretta. The island constitutes an Integral Natural Reserve and a Marine Protected Area. We assessed marine litter accumulation on sandy beaches of the island and analysed their spatial patterns using two sampling methods: at a fine scale, sand samples from 1 × 1 m squares were collected, identifying debris larger than 1 mm; at a coarse scale, drone surveys were conducted to identify visible marine debris (>25 mm) in aerial images. We sampled six points on three beaches of the island: Achados (three points), Francisca (two points) and Palmo Tostão (one point). Then, we modelled the abundance of marine debris using topographical variables as explanatory factors, derived from digital surface models (DSM). Our findings reveal that the island is a significant repository for marine litter (>84% composed of plastics), with up to 917 plastic items per m2 in the sand samples and a maximum of 38 macro-debris items per m2 in the drone surveys. Plastic fragments dominate, followed by plastic pellets (at the fine-scale approach) and fishing materials (at the coarse-scale approach). We observed that north-facing, higher-elevation beaches accumulate more large marine litter, while slope and elevation affect their spatial distribution within the beach. Achados Beach faces severe marine debris pollution challenges, and the upcoming climate changes could exacerbate this problem.


Assuntos
Areia , Resíduos , Resíduos/análise , Cabo Verde , Plásticos/análise , Praias , Monitoramento Ambiental/métodos
8.
Dis Aquat Organ ; 105(3): 183-91, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23999702

RESUMO

Two juvenile (curved carapace lengths: 28 and 30 cm) loggerhead sea turtles Caretta caretta with precocious male external characteristics were admitted to the ARCA del Mar rescue area at the Oceanogràfic Aquarium in Valencia, Spain, in 2009 and 2010. Routine internal laparoscopic examination and subsequent histopathology confirmed the presence of apparently healthy internal female gonads in both animals. Extensive tissue biopsy and hormone induction assays were consistent with female sex. To the best of our knowledge, this is the first report of pseudohermaphroditism in loggerhead sea turtles based on sexual external characteristics and internal laparoscopic examination. Our findings suggest that the practice of using external phenotypical characteristics as the basis for gender identification in sea turtles should be reevaluated. Future research should focus on detecting more animals with sexual defects and their possible effects on the sea turtle population.


Assuntos
Transtornos do Desenvolvimento Sexual/veterinária , Tartarugas , Animais , Feminino , Ovário/anatomia & histologia , Ovário/fisiologia
9.
Mar Pollut Bull ; 195: 115550, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37722265

RESUMO

Plastic pollution is a global environmental issue affecting multiple ecosystems, namely sea turtle nesting grounds. We analysed the potential chemical contamination caused by plastic debris in loggerhead turtle (Caretta caretta) nests, focusing on polybrominated diphenyl ethers (PBDEs, a class of flame retardants). For that, we conducted a field experiment in a turtle hatchery (Cabo Verde) by placing plastic fragments in the nests at two depths: surface and ~20 cm. We evaluated the nests' success and quantified the levels of PBDEs in the sand using GC-MS/MS. Our results suggest that plastics on the nests' surface can leak contaminants, infiltrating the sand up to 20 cm. Buried plastics showed no relevant leakage of chemicals. While hatching and emergence success was unaffected, we found a relationship between leucistic embryos and contamination levels. Our study highlights the threats of plastic accumulation on beaches, which can potentially leak chemicals and contaminate turtle nests.

10.
Cont Lens Anterior Eye ; 46(4): 101854, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37173175

RESUMO

PURPOSE: To conduct a review of the literature in order to identify the potential association between physical activity or exercise and the objective signs and/or subjective symptoms of dry-eye disease. METHODS: A review of PubMed and Web of Science databases was performed, according to the PRISMA guidelines. The papers included in the review addressed the relationship of physical activity or exercise with dry-eye associated signs (changes in tear volume, osmolarity or biochemical composition) and/or subjective symptoms. RESULTS: A total of 16 papers were included. In eight, the changes in tear film volume, osmolarity and/or biochemical composition were studied after a single, acute bout of aerobic exercise. In another eight, changes in dry-eye associated symptoms were studied in relation to the habitual practice of physical activity or to prescribed exercise programmes. Acute responses of the tear film to exercise included: a) an increase of tear volume, without an increase of the tear break-up time; b) a trend to increase tear osmolarity, although within its physiological range; and c) a reduced concentration of several cytokines, and other molecular markers of inflammation or oxidative stress. Long-term exposure to physical activity or exercise programmes was associated with relief of dry-eye associated symptoms and a trend to increased tear break-up time. CONCLUSIONS: Despite a high heterogeneity in the studied population, study designs and methods, the current body of evidence suggests a potential role for physical activity as a modulatory stimulus for the proper functioning of the tear film and/or the relief of dry-eye symptoms.


Assuntos
Síndromes do Olho Seco , Humanos , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/terapia , Lágrimas/química , Concentração Osmolar , Biomarcadores
11.
Data Brief ; 43: 108432, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35818353

RESUMO

We provide the raw data of 44 satellite-tracked loggerhead sea turtles from different life-stages collected between 2016 and 2018. Depending on life-stage and tag availability a different satellite tag was attached to the loggerhead carapace. Location data were collected using the Argos system. We made publically available for the first time in the Mediterranean: (i) the satellite-tracking data for 17 one-year-aged post-hatchlings of loggerhead sea turtle came from two nests laid on the Mediterranean Spanish coast; (ii) the satellite-tracking data for 4 loggerhead nesting females collected from nesting events occurred on the Spanish Mediterranean coast. Besides, another 23 juvenile and adult loggerhead sea turtles were monitored and their data were made also available. Our dataset provide the turtle identity name or number, the date and coordinates of the location data, and the Argos location class associated. Our data contribute to the knowledge about the spatial use of the loggerhead sea turtle in the Mediterranean Sea and could be used in further analysis regarding habitat use and dispersal of this species in the Mediterranean Sea. Specially, nesting females and post-hatchlings data contribute to shed light about these life-stages related to nesting events out of the usual nesting range in the western Mediterranean, for which data still remains scarce. Also, data could be compared to further similar research in satellite-tracking loggerhead sea turtles in the Mediterranean basin.

12.
Obes Surg ; 32(4): 1130-1140, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35048250

RESUMO

PURPOSE: There is no consensus on the best exercise recommendation for women affected by severe obesity while they are waiting for bariatric surgery. For this reason, the effects of a combination of aerobic exercise performed at the intensity at which maximal fat oxidation is reached (Fatmax) with low-intensity resistance training were studied. MATERIALS AND METHODS: Twenty sedentary middle-aged Caucasian women (43.2 ± 7.5 years, BMI = 46.5 ± 5.9 kg·m-2) were allocated to a control group (CG, n = 10) that followed solely the conventional preoperative care or to an experimental group (EG, n = 10) that, in addition, performed a 12-week individualized and supervised physical activity program (PAP) that combined aerobic training at Fatmax with low-intensity resistance training. RESULTS: After the PAP, maximal fat oxidation during exercise increased in the EG (0.187 ± 0.068 vs 0.239 ± 0.080 g·min-1, p = 0.025, pre vs. post, respectively), but resting fat oxidation did not (0.088 ± 0.034 vs 0.092 ± 0.029 g·min-1, p = 0.685, pre vs. post, respectively). Additionally, the resting metabolic rate in the EG was also unchanged (1869 ± 406 vs. 1894 ± 336 kcal; p = 0.827, pre vs. post, respectively), probably because of the effects of resistance training on the maintenance of fat-free mass. No significant changes were observed in the CG. CONCLUSION: A PAP that combines aerobic exercise at Fatmax with low resistance training may counteract some of the deleterious side effects of the standard presurgical care of women waiting for bariatric surgery and increase maximal fat oxidation during exercise.


Assuntos
Cirurgia Bariátrica , Obesidade Mórbida , Treinamento Resistido , Exercício Físico/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Músculos , Obesidade Mórbida/cirurgia , Consumo de Oxigênio/fisiologia
13.
J Hered ; 102(6): 666-77, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21934114

RESUMO

Juvenile loggerhead sea turtles (Caretta caretta) from Atlantic nesting populations migrate into the western Mediterranean, where they share feeding grounds with turtles originating in the Mediterranean. In this scenario, male-mediated gene flow may lead to the homogenization of these distant populations. To test this hypothesis, we genotyped 7 microsatellites from 56 Atlantic individuals sampled from feeding grounds in the western Mediterranean and then compared the observed allele frequencies with published data of 112 individuals from Mediterranean nesting beaches. Mediterranean populations were found to be genetically differentiated from the Atlantic stock reaching the western Mediterranean (F(st) = 0.029, P < 0.001); therefore, the possible mating events between Atlantic and Mediterranean individuals are not sufficient to homogenize these 2 areas. The differentiation observed between these 2 areas demonstrates that microsatellites are sufficiently powerful for mixed stock analysis and that individual assignment (IA) tests can be performed in combination with mitochondrial DNA (mtDNA) analysis. In a set of 197 individuals sampled in western Mediterranean feeding grounds, 87% were robustly assigned to Atlantic or Mediterranean groups with the combined marker, as compared with only 52% with mtDNA alone. These findings provide a new approach for tracking the movements of these oceanic migrants and have strong implications for the conservation of the species.


Assuntos
DNA Mitocondrial/genética , Genética Populacional/métodos , Reprodução/genética , Tartarugas/genética , Migração Animal , Animais , Oceano Atlântico , Comportamento Alimentar/fisiologia , Feminino , Fluxo Gênico , Variação Genética , Haplótipos , Masculino , Mar Mediterrâneo , Repetições de Microssatélites , Mitocôndrias/genética , Filogeografia , Análise de Sequência de DNA , Especificidade da Espécie
14.
MethodsX ; 8: 101518, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34754789

RESUMO

This paper evaluated the efficiency of beach hatcheries as a conservation tool for threatened sea turtle clutches. During six nesting seasons (2013 to 2018), several thousand high-risk clutches from loggerhead turtles (Caretta caretta) were relocated to a hatchery constructed on the same beach, within the Sea Turtle Natural Reserve (STNR, Boa Vista Island, Cabo Verde). Some parameters like hatching success; incubation period, hatchlings' morphology and their behavioral response were compared to in-situ clutches.•Our findings confirmed that the in-situ nests within the STNR had extremely high egg mortality that was usually over 70 %. Mean hatching success of clutches relocated to hatcheries was significantly higher than in-situ clutches with mean values between 70 to 85 % (p < 0.0001).•No significant differences were observed in the incubation period (p = 0.786) and morphology of hatchlings (all p > 0.05) between relocated and in-situ clutches.•This study provided a detailed method and recommendations for sea turtle clutches relocation to the hatchery, that can be beneficial for endangered sea turtle population specially where hatching success is very low.

15.
Front Med (Lausanne) ; 8: 767967, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869482

RESUMO

After the unilateral inflammation or nerve lesion of the ocular surface, the ipsilateral corneal sensory nerve activity is activated and sensitized, evoking ocular discomfort, irritation, and pain referred to the affected eye. Nonetheless, some patients with unilateral ocular inflammation, infection, or surgery also reported discomfort and pain in the contralateral eye. We explored the possibility that such altered sensations in the non-affected eye are due to the changes in their corneal sensory nerve activity in the contralateral, not directly affected eye. To test that hypothesis, we recorded the impulse activity of the corneal mechano- and polymodal nociceptor and cold thermoreceptor nerve terminals in both eyes of guinea pigs, subjected unilaterally to three different experimental conditions (UV-induced photokeratitis, microkeratome corneal surgery, and chronic tear deficiency caused by removal of the main lacrimal gland), and in eyes of naïve animals ex vivo. Overall, after unilateral eye damage, the corneal sensory nerve activity appeared to be also altered in the contralateral eye. Compared with the naïve guinea pigs, animals with unilateral UV-induced mild corneal inflammation, showed on both eyes an inhibition of the spontaneous and stimulus-evoked activity of cold thermoreceptors, and increased activity in nociceptors affecting both the ipsilateral and the contralateral eye. Unilateral microkeratome surgery affected the activity of nociceptors mostly, inducing sensitization in both eyes. The removal of the main lacrimal gland reduced tear volume and increased the cold thermoreceptor activity in both eyes. This is the first direct demonstration that unilateral corneal nerve lesion, especially ocular surface inflammation, functionally affects the activity of the different types of corneal sensory nerves in both the ipsilateral and contralateral eyes. The mechanisms underlying the contralateral affectation of sensory nerves remain to be determined, although available data support the involvement of neuroimmune interactions. The parallel alteration of nerve activity in contralateral eyes has two main implications: a) in the experimental design of both preclinical and clinical studies, where the contralateral eyes cannot be considered as a control; and, b) in the clinical practice, where clinicians must consider the convenience of treating both eyes of patients with unilateral ocular conditions to avoid pain and secondary undesirable effects in the fellow eye.

16.
Front Med (Lausanne) ; 8: 709712, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765614

RESUMO

Perfluorohexyloctane (F6H8) eyedrops have been recently introduced in Europe as a product to treat dry eye disease, based on its ability to reduce tear film instability in Meibomian gland dysfunction and evaporative dry eye disease, although its mechanism of action is still unknown. In the present pilot study, we evaluated the effects of the ocular instillation of a single drop of commercial F6H8 eyedrops in 20 healthy humans (9 women/11 men), measuring: (a) Corneal surface temperature (CST) from infrared video images; (b) tear volume using phenol red threads; (c) blinking frequency; and (d) ocular surface sensations (cold, dryness, pricking, foreign body, burning, itching, gritty, eye fatigue, watering eyes, and light-evoked discomfort sensations; scored using 10 cm Visual Analog Scales), before and 5-60 min after F6H8 or saline treatment. CST decreased and tearing and blinking frequency increased significantly after F6H8 but not after saline solution. When applied unilaterally, CST decreased only in the F6H8-treated eye. No sensations were evoked after F6H8 or saline. The corneal surface temperature reduction produced by topical F6H8 does not evoke conscious ocular sensations but is sufficient to increase the activity of corneal cold thermoreceptors, leading to an increased reflex lacrimation and blinking that may relieve dry eye condition thus reducing ocular discomfort and pain.

17.
Biology (Basel) ; 10(8)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34440015

RESUMO

This study aimed to explore if the acute variations in plasma concentration of α-calcitonin gene-related peptide (αCGRP) induced by a single maximal exercise bout may be associated to cardiorespiratory fitness and carbohydrate oxidation in humans. Twelve young adult Caucasian men (24.3 ± 0.9 years-old; 179.2 ± 1.9 cm of height; 23.9 ± 0.6 kg·m-2 body mass index) performed a graded exercise test. A venous catheter was placed before testing, and blood samples were taken at baseline, maximal effort and recovery. αCGRP was measured in plasma using a commercial double-sandwich enzyme-linked-immunoassay. A two-way repeated measurements ANOVA was used to compare the values obtained at baseline, maximal effort and recovery. In the whole sample, αCGRP increased at maximal effort and its concentration correlated directly, albeit non-significantly, with the muscle mass normalised VO2, VCO2, carbohydrate oxidation and relative power. Two thirds of the participants showed an increase in αCGRP concentration at maximal effort. Post hoc analysis showed that in these individuals, the muscle mass normalised VO2, VCO2, carbohydrate oxidation rate and relative power were higher than in the participants lacking this molecular response. Therefore, our data suggest that (a) a majority of young men respond to exercise with an increase in blood αCGRP concentration; and (b) individuals exhibiting this response also show a higher cardiorespiratory fitness, carbohydrate oxidation and work performed. These findings suggest that this neuropeptide could act as an exerkine with potential effects on physical performance.

18.
Rev Biol Trop ; 58(3): 943-54, 2010 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-20737848

RESUMO

Hatchling emergence to the beach surface from deep sand nests occurs without parental care. Social behaviour among siblings is crucial to overcome this first challenge in sea turtles life. This study, carried out at the Caribbean coast of Colombia, describes the emergence social behaviour of hatchlings from eight nests, and assess the nests translocation effects on temporal patterns of emergence. For the first time, we propose that space released by dehydration of shelled albumen globes (SAGs) at the top of the clutch, might be a reproductive advantage, while facilitating neonates to group together in a very limited space, and favouring the synchrony of emergence. The mean time of groups emergence was of 3.3 days, varying between 1 and 6 days. We found that relocation of the nests did not significantly affect the temporal pattern of emergence, which was mainly nocturnal (77.7% of natural nests and 81.7% of translocated ones). The maximum number of emergences to the surface occurred at the lowest air temperatures (22:00h-06:00h). The selective advantage of this pattern is probably related to the greater rate of predation and mortality by hyperthermia observed during the day.


Assuntos
Animais Recém-Nascidos/fisiologia , Comportamento de Nidação/fisiologia , Oviposição , Tartarugas/fisiologia , Animais , Praias , Colômbia , Feminino , Fatores de Tempo
19.
Environ Toxicol Chem ; 28(7): 1500-5, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19220079

RESUMO

Although many studies have assessed the effects of water pollution on amphibians, few have focused on the alteration of vital behaviors. Newt species usually display complex courtship behavior that may be altered by sublethal levels of contaminants. We analyzed the effects of ammonium nitrate and water acidification on courtship behavior of the Iberian newt (Lissotriton boscai). We exposed newt couples to three treatments (control, nominal 90 mg N--NO3NH4/L, and nominal pH 4) and recorded the occurrence of each of the three courtship phases (orientation, static display, and spermatophore transfer) as well as the latency to initiate courtship, overall courtship time, male perseverance, and female responsiveness. Major effects were observed in the acid treatment. Low pH inhibited orientation. None of the control couples failed to court, whereas 17% of couples from the low-pH treatment did not perform any courtship movement. Latency to initiate courting was twice as high in couples exposed to acidification as in controls. Low pH also affected the overall time of courtship and perseverance time of males in unsuccessful encounters. Ammonium nitrate did not cause any significant effect. Only the female response index and the duration of the tail-fanning movement (the major display during L. boscai courtship) were slightly reduced by the fertilizer. We report a pollution-mediated alteration of courtship behavior, to our knowledge for the first time, in amphibians. This kind of sublethal effect should be considered when estimating potential impacts of water pollution on natural populations.


Assuntos
Comportamento Animal/efeitos dos fármacos , Corte , Nitratos/toxicidade , Salamandridae/fisiologia , Poluentes Químicos da Água/toxicidade , Ácidos , Animais , Feminino , Concentração de Íons de Hidrogênio , Masculino , Nitratos/química , Poluentes Químicos da Água/química
20.
Sports (Basel) ; 7(3)2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30934623

RESUMO

Bariatric surgery (BS) is considered the most effective treatment for morbid obesity. Preoperative body weight is directly associated with a higher surgical morbimortality and physical activity could be effective in the preparation of patients. The aim of this study is to determine the effects of a six-month exercise training program (ETP), combining high-intensity interval training (HIIT) and resistance training in patients awaiting BS. Six candidates awaiting BS (38.78 ± 1.18 kg·m-2; 38.17 ± 12.06 years) were distributed into two groups: the ETP group (experimental group (EG), n = 3) and a control group (CG, n = 3). Anthropometrical and blood pressure (BP), cardiorespiratory fitness and maximal strength were registered before and after the ETP. The EG participated in 93.25% of the sessions, showing reductions in body mass index (BMI) compared to the CG (34.61 ± 1.56 vs. 39.75 ± 0.65, p = 0.006, ANOVA). The inferential analysis showed larger effects on BMI, excess body weight percentage and fat mass, in addition to small to moderate effects in BP and the anthropometric measurements. Peak oxygen uptake normalized to fat-free mass showed likely positive effects with a probability of >95⁻99%. A six-month ETP seems to be a positive tool to improve body composition, cardiometabolic health, and fitness level in patients awaiting BS, but a larger sample size is needed to confirm these findings.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA