RESUMEN
BACKGROUND: Patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) and disease-related poor prognostic factors are not well characterized. We aimed to describe patient demographics, disease characteristics, treatment patterns and patient-reported outcomes in a subset of HR+/HER2- ABC patients with these factors [at the time when cyclin-dependent kinase (CDK) 4 and 6 inhibitors were being introduced] and understand how these factors informed treatment decisions at the time of the survey. METHODS: Real-world data were derived from a large, multinational, point-in-time survey of oncologists and their consulting patients with HR+/HER2- ABC in the EU5 and USA over March-June 2017, at the start of the changing treatment landscape. Analysis focused on four poor prognostic factors: visceral metastases, liver metastases (subset of visceral metastases), progesterone receptor-negative status and high tumor grade. RESULTS: In total, 2259 patients with HR+/HER2- ABC had records eligible for this analysis. At least one poor prognostic factor was present in 63% of patients (most common visceral metastases; least common progesterone receptor-negative status), with varying degrees of overlap between factors. For physician-reported outcomes, pain increased, whereas performance status and activities of daily living declined with presence of poor prognostic factors, especially liver metastases. No clear trends were observed for patient-reported outcomes. Treatment with combined endocrine therapy plus CDK4 and 6 inhibitors was infrequent, as these agents were entering the market. CONCLUSIONS: More than 60% of the HR+/HER2- ABC Adelphi Real World Disease Specific Programme™ sample had ≥1 disease-related poor prognostic factor, and patients appeared to be heterogeneous regarding occurrence and distribution of these factors. These patients typically have increased pain and reduced performance status, highlighting the importance of implementing effective therapy with CDK4 and 6 inhibitors. Future studies could inform how the treatment landscape has evolved over time with respect to patients with poor prognostic factors.
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Neoplasias de la Mama , Actividades Cotidianas , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/epidemiología , Femenino , Humanos , Medición de Resultados Informados por el Paciente , Pronóstico , Receptor ErbB-2/uso terapéutico , Receptores de Estrógenos/uso terapéuticoRESUMEN
Evidence from mammals and aves alludes to a possibly conserved seasonal photoperiod induced neuroendocrine cascade which stimulates subsequent sexual maturation however our understanding of this mechanism in teleosts is lacking. Unlike all teleosts studied to date, the Atlantic cod (Gadus morhua) is a short day breeder with the reduction in day-length from the summer solstice stimulating gametogenesis. Cod specific orthologues of eya3, tshß and dio2 were identified and their expression was monitored in the brain and pituitary of cod held under either stimulated or inhibited photoperiod conditions. While no differential expression was apparent in brain dio2 & tshß and pituitary tshß, there was significant temporal variation in expression of pituitary eya3 under the SNP treatment, with expression level elevating in association with active gametogenesis. Under the LL treatment, sexual maturation was inhibited and there was a corresponding suppression of eya3 expression. In a second study the impact of size/energetic status on the initiation of sexual maturation was investigated. In the feed restricted population maturation was significantly suppressed (5% sexually mature) compared to the ab libitum fed stock (95% sexually mature) with there being a concomitant significant suppression in pituitary eya3 expression. Overall, these results suggest that pituitary eya3 has the potential to act as an integrator of both environmental and energetic regulation of sexual maturation of cod. Being the first account of eya3 induction in a short day breeding teleost, the conserved association with stimulation of reproduction and not seasonal state indicates that the upstream drivers which initiate the pathway differ among vertebrates according to their breeding strategies, but the pathway itself and its role in the reproductive cascade appears to be conserved across the vertebrate clade.
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Fenómenos Fisiológicos Nutricionales de los Animales , Gadus morhua/fisiología , Sistemas Neurosecretores , Fotoperiodo , Maduración Sexual , Animales , Ritmo Circadiano/fisiología , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Masculino , Filogenia , Hipófisis/metabolismo , Reproducción/fisiología , Estaciones del Año , Factores de Tiempo , VertebradosRESUMEN
Atypical Aeromonas salmonicida (aAs) and Vibrionaceae related species are bacteria routinely recovered from diseased ballan wrasse used as cleaner fish in the Atlantic salmon farming industry. Autogenous (i.e. farm specific inactivated) multivalent vaccines formulated from these microorganisms are widely used to protect farmed wrasse despite limited experimental proof that they are primary pathogens. In this study, the components of a commercial multivalent injection vaccine containing four strains of Aeromonas salmonicida and one strain of Vibrio splendidus previously isolated from ballan wrasse in Scotland, were tested for infectivity, pathogenicity and virulence via intra peritoneal injection at pre-deployment size (25-50 g) and the efficacy of the vaccine for protection against aAs assessed. Injection with 3.5 × 109, 8 × 109 1.8 × 109 and 5 × 109 cfu/fish of Vibrio splendidus, V. ichthyoenteri, Aliivibrio logeii and A. salmonicida, respectively, did not cause significant mortalities, lesions or clinical signs after a period of 14 days. IP injection with both aAs and Photobacterium indicum successfully reproduced the clinical signs and internal lesions observed during natural outbreaks of the disease. Differences in virulence (LD50 at day 8-post infection of 3.6 × 106 cfu/fish and 1.6 × 107 cfu/fish) were observed for two aAs vapA type V isolates. In addition, the LD50 for Photobacterium indicum was 2.2 × 107 cfu/fish. The autogenous vaccine was highly protective against the two aAs vapA type V isolates after 700-degree days of immunisation. The RPSFINAL values for the first isolate were 95 and 91% at 1 × 106 cfu/fish and 1 × 107 cfu/fish, respectively, and 79% at 1 × 107 cfu/fish for the second isolate tested. In addition, significantly higher anti aAs seral antibodies (IgM), were detected by ELISA in vaccinated fish in contrast with control (mock vaccinated) fish. These results suggest wrasse can be effectively immunised and protected against aAs infection by injection with oil adjuvanted vaccines prepared with inactivated homologous isolates.
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Autovacunas/administración & dosificación , Enfermedades de los Peces/inmunología , Peces/inmunología , Vacunación/veterinaria , Aeromonas salmonicida/fisiología , Animales , Enfermedades de los Peces/microbiología , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/veterinaria , Escocia , Vibrionaceae/fisiologíaRESUMEN
Healthy and/or moribund farmed and wild ballan wrasse Labrus bergylta (>0.5 to 900 g) were sampled from hatcheries (n = 2) and Atlantic salmon Salmo salar cage sites (n = 8) in Scotland between February 2016 and October 2018. Less than half of the sampled individuals (n = 43; 32.3%) had been vaccinated (autogenous polyvalent vaccine; dip and/or injection) against atypical furunculosis (type V and VI), while 20 (15.0%) fish were not vaccinated, and the rest (70 individuals, 52.7%) were of unknown vaccination status. Swab samples from skin lesions, gill, liver, spleen and kidney were inoculated onto a variety of bacteriological agar plates, and bacteriology identification and sequencing analysis was performed on significant bacterial colonies. Atypical Aeromonas salmonicida (aAs) vapA type V was the predominant bacterial species (70/215 bacterial isolates, 32.5% of bacterial samples; 43/117 positive individual fish, 36.8%) isolated in this survey followed by Vibrio species, which were the most geographically prevalent bacteria. Photobacterium indicum/profundum was also isolated from L. bergylta for the first time during this study. The collection of these bacterial isolates provides useful information for disease management. Identifying the aAs isolates involved in disease in ballan wrasse could provide vital information for improving/updating existing autogenous vaccines.
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Aeromonas salmonicida , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas/veterinaria , Perciformes , Vibriosis/veterinaria , Vibrio , Animales , Photobacterium , EscociaRESUMEN
Primordial germ cells (PGCs) are specified by maternally provided determinants in fish. PGCs migrate then into prospective gonadal sites during early development and give rise to germ cell lineage. PGC disrupted animals do not sexually mature which has a range of commercial as well as environmental benefits. To find potential target genes for sterilisation of Nile tilapia, relative mRNA abundance patterns and tissue distribution of four nanos, two piwil, dnd1, vasa and three pum genes were investigated during ontogenic development from unfertilised eggs to newly hatched larvae and in adult tissues, respectively. The ontogenic pattern of RNA abundance revealed that all the investigated gene transcripts are maternally deposited to varying degrees, except for nanos2 which is not expressed in eggs. The ontogenic patterns of relative RNA abundance could be grouped into three categories. The first one, including nanos3, piwil1, piwil2, dnd1 and vasa, showed abundant transcript levels during early developmental stages which are then degraded during the period of maternal to zygotic transition between blastula and gastrula stages with a reduction in expression of four to five orders of magnitude by hatching stage. Another, including pum2 and pum3, showed similar patterns to the first group, but the transcript levels are reduced by only two orders of magnitude. The third group, including nanos1a, nanos1b and pum1, was characterised by a zygotic increase. nanos2 had no detectable transcripts until hatching stage. The tissue screening of nanos1a, nanos1b, pum1, pum2 and pum3 showed that they are expressed in various tissues, implying their potential pleiotropic effects in these tissues apart from gonads. In contrast, nanos3, piwil1, piwil2, dnd1 and vasa appeared to be exclusively expressed in gonads (both ovary and testis), and nanos2 showed testis-specific expression. Based on these results nanos3, piwil1, piwil2, dnd1 and vasa were prioritised among the 11 selected genes as potential target genes for sterilisation in Nile tilapia as they have no significant zygotic expression during embryogenesis, they are expressed exclusively in gonads and maternally deposited. These features suggest a potential role of these genes in the specification and maintenance of PGCs during the ontogenic development of Nile tilapia.
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Cíclidos/genética , Regulación del Desarrollo de la Expresión Génica/genética , Tilapia/genética , Animales , Cíclidos/crecimiento & desarrollo , Desarrollo Embrionario/genética , Femenino , Ontología de Genes , Células Germinativas/crecimiento & desarrollo , Gónadas/crecimiento & desarrollo , Masculino , Óvulo/crecimiento & desarrollo , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Tilapia/crecimiento & desarrollo , Cigoto/crecimiento & desarrolloRESUMEN
This study confirmed that observations of blue-green colouration in plasma fractions of the ballan wrasse Labrus bergylta were caused by the linear tetra-pyrrole biliverdin and that the molecule was of the physiologically relevant IXα isomer. Accumulation appears driven by chromogenic association with an unknown protein moiety which precludes enzymatic reduction and would suggest active management. It was demonstrated that the pigment did not fluctuate relative to ontogeny, or indeed binary gender in the species of interest, but mobilisation and depletion in the subset of individuals undergoing sex change at the time of study supports a potential association with gender inversion processes. It is of note that although biliverdin does have some effect on external colouration, the evidence is indicative that crypsis is a supplementary function thus other factors must be considered.
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Biliverdina/aislamiento & purificación , Perciformes/sangre , Plasma/química , Animales , Femenino , MasculinoRESUMEN
This study compares diagnostic imaging tools in detecting the parasitic swimbladder nematode Anguillicoloides crassus in Anguilla anguilla (L.) and focuses on ultrasound in an attempt to develop a non-destructive, field diagnostic test. Ultrasound use could allow the parasite to be diagnosed without decreasing the number of critically endangered European eels through post-mortem. In the preliminary study, eels were examined with computed radiography, computed tomography, magnetic resonance imaging, 14 MHz high-end ultrasound and 5 MHz low-end portable ultrasound, and the results were compared with post-mortem findings. This ultrasound scanning technique did not produce any promising results. A second batch of eels was examined using the same high-end and low-end ultrasounds, but employing a different scanning technique and comparing the results with post-mortem. This second study, scanning along the midline from below, allowed for the detection of anomalies associated with moderately infected animals. None of the eels used in this study were severely infected; thus, no conclusions can be made regarding the use of ultrasound in those animals. Overall, it was found that none of the techniques were useful in diagnosing mildly infected individuals; therefore, no single diagnostic imaging tool is sensitive enough to replace post-mortem for definite diagnosis.
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Sacos Aéreos/patología , Anguilla , Diagnóstico por Imagen/veterinaria , Dracunculoidea/fisiología , Enfermedades de los Peces/diagnóstico por imagen , Infecciones por Spirurida/veterinaria , Ultrasonografía/veterinaria , Sacos Aéreos/parasitología , Animales , Enfermedades de los Peces/parasitología , Enfermedades de los Peces/patología , Imagen por Resonancia Magnética/veterinaria , Radiografía/veterinaria , Escocia , Infecciones por Spirurida/diagnóstico por imagen , Infecciones por Spirurida/parasitología , Infecciones por Spirurida/patología , Tomografía Computarizada por Rayos X/veterinariaRESUMEN
In wild ballan wrasse Labrus bergylta, mass-length relationships were not different between genders, and positive allometry was found in the mixed-gender population. Male-biased sexual size dimorphism was significant and the most effective morphometric method for sexing L. bergylta outside of the species spawning window used body mass (M(B) in g), total body length (L(T) in mm) and Fulton's condition factor (K) as discriminant variables to predict gender with 91% accuracy. The discriminant score (S(D)) of a specimen can be calculated as S(D) = 0.01 M(B)- 0.016 L(T)- 3.835 K + 6.252 to predict its gender as female or male if S(D) is < 1.459 or S(D) is > 1.504, respectively. There was a potential trend towards earlier sexual inversion compared to previous studies at comparable latitudes. Sex change is a phenotypically plastic trait under social control in haremic fishes and should be monitored in increasingly exploited L. bergylta.
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Tamaño Corporal , Perciformes/fisiología , Caracteres Sexuales , Animales , Femenino , Masculino , Razón de MasculinidadRESUMEN
It has been observed that microbubbles may pass through the pulmonary circulation of dogs and humans during exercise. In humans, this phenomenon has been associated with lower pulmonary artery pressures, enhanced right ventricular function and greater exercise capacity. In the exercising Thoroughbred horse, extraordinarily high cardiac outputs exert significant pulmonary vascular stresses. The aim of this study was to determine, using contrast echocardiography, whether Thoroughbred horses performing strenuous exercise developed pulmonary transit of agitated contrast microbubbles (PTAC). At rest, agitated contrast was observed in the right ventricle, but not in the left ventricle. However, post-exercise microbubbles were observed in the left ventricle, confirming the occurrence of PTAC with exercise but not at rest. Further investigation is warranted to investigate whether this phenomenon may be associated with superior physiology and performance measures as has been implicated in other species.
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Medios de Contraste/farmacología , Caballos/fisiología , Pulmón/irrigación sanguínea , Microburbujas/veterinaria , Condicionamiento Físico Animal/fisiología , Circulación Pulmonar/fisiología , Animales , MasculinoAsunto(s)
Explotaciones Pesqueras/métodos , Peces/fisiología , Procesamiento de Imagen Asistido por Computador/métodos , Animales , Embrión no Mamífero/embriología , Embrión no Mamífero/fisiología , Desarrollo Embrionario , Peces/embriología , Peces/crecimiento & desarrollo , Lenguado/embriología , Lenguado/crecimiento & desarrollo , Lenguado/fisiología , Óvulo/fisiologíaAsunto(s)
Proteínas de Peces/genética , Regulación del Desarrollo de la Expresión Génica , Kisspeptinas/genética , Receptores Acoplados a Proteínas G/genética , Dorada/genética , Animales , Proteínas de Peces/metabolismo , Kisspeptinas/metabolismo , Larva/genética , Larva/crecimiento & desarrollo , Larva/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Receptores Acoplados a Proteínas G/metabolismo , Dorada/crecimiento & desarrollo , Dorada/metabolismoRESUMEN
In the present study, we developed and validated real-time quantitative RT-PCR assays for a suite of genes involved in the brain-pituitary gonadal axis in fish including kisspeptin genes and its receptor (Kiss1, kiss2, kissr4) and gonadotropin-releasing hormone genes (sbGnRH, sGnRH, cGnRHII) in the brain, and gonadotropin genes (fshß and lhß) in the pituitary. Sex steroid profiles (T and 11-KT) and gonadal development were also studied over a full annual reproductive cycle in adult male sea bass. The cDNA partial sequence of sea bass kissr4 encoding 185 amino acids showed a high degree of conservation with other fish kissr4 subtype. Results clearly showed a seasonal profile for Kiss1, kiss2 and kissr4 mRNAs. Kissr4, fshß and lhß levels increased gradually and peaked during spermatogenesis (January) while Kiss1, kiss2, cGnRH-II as well as steroids showed peaks during early spawning (March). No significant seasonal changes were observed for sbGnRH and sGnRH expression. These results support the possible involvement of the kiss genes and their receptor (kissr4) in the seasonal control sea bass reproduction. However, a lack of correlation between kiss genes and sbGnRH expression and the mismatch between kisspeptin and the onset of gonadotropin surge contrast with previous findings.
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Lubina/metabolismo , Kisspeptinas/metabolismo , Reproducción/fisiología , Animales , Hormona Liberadora de Gonadotropina/metabolismo , Masculino , Estaciones del AñoRESUMEN
In order to investigate the potential role of the kisspeptin system in the entrainment of reproduction in Atlantic cod, qPCR assays were developed for kiss2 and its receptor kissr4. mRNA expression was monitored in the brain over a full reproductive cycle in 2 populations of males and females: 1) a maturing population (exposed to simulated natural photoperiod, SNP) and 2) a maturation inhibited population (exposed to constant light, LL). Pituitary expression of gonadotropin subunit mRNA (fshß and lhß) was also measured. Results from this study indicated no clear temporal pattern in expression of kiss2 or kissr4 mRNAs in either population of cod, however acute elevations were apparent in maturing (SNP) individuals, namely an elevation in kiss2 in vitellogenic females and spermiating males and spikes in kissr4 during early vitellogenesis in females and spermatogenesis in males. Gonadotropin mRNA expression displayed strong amplitudinal changes over time with fshß and lhß mRNA expression increasing towards spawning in maturing individuals. No firm conclusions on the role of the kisspeptin system in cod puberty can be drawn at this stage, however mRNA increases in kiss2 and kissr4 may elude to conserved kisspeptin functions in cod and opens up interesting avenues on potential gender specific functions.
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Gadus morhua/crecimiento & desarrollo , Gadus morhua/genética , Gonadotropinas/genética , Kisspeptinas/genética , Fotoperiodo , Maduración Sexual/genética , Animales , Clonación Molecular , Femenino , Perfilación de la Expresión Génica , Masculino , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , Especificidad de la EspecieRESUMEN
In the last two decades, there has been a significant change in the technology of clinical thermometry. Mercury-in-glass thermometers have been replaced with electronic devices that offer faster readings with minimal inconvenience to the patient. Each user should be aware of the characteristics and limitations of these devices to interpret correctly the temperature reading on the display. The article provides an insight into commonly used clinical thermometers, how they determine each temperature reading and, crucially, how users affect the measurement process.
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Benchmarking , Temperatura Corporal , Evaluación en Enfermería/métodos , Termómetros/provisión & distribución , Axila , Sesgo , Calibración , Oído , Frente/irrigación sanguínea , Humanos , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Monitoreo Fisiológico/enfermería , Mucosa Bucal , Evaluación en Enfermería/normas , Recto , Reproducibilidad de los Resultados , Arterias Temporales , Termografía/instrumentación , Termografía/métodos , Termografía/enfermería , Termómetros/normas , Membrana TimpánicaRESUMEN
Seasonality is an important adaptive trait in temperate fish species as it entrains or regulates most physiological events such as reproductive cycle, growth profile, locomotor activity and key life-stage transitions. Photoperiod is undoubtedly one of the most predictable environmental signals that can be used by most living organisms including fishes in temperate areas. This said, however, understanding of how such a simple signal can dictate the time of gonadal recruitment and spawning, for example, is a complex task. Over the past few decades, many scientists attempted to unravel the roots of photoperiodic signalling in teleosts by investigating the role of melatonin in reproduction, but without great success. In fact, the hormone melatonin is recognized as the biological time-keeping hormone in fishes mainly due to the fact that it reflects the seasonal variation in daylength across the whole animal kingdom rather than the existence of direct evidences of its role in the entrainment of reproduction in fishes. Recently, however, some new studies clearly suggested that melatonin interacts with the reproductive cascade at a number of key steps such as through the dopaminergic system in the brain or the synchronization of the final oocyte maturation in the gonad. Interestingly, in the past few years, additional pathways have become apparent in the search for a fish photoneuroendocrine system including the clock-gene network and kisspeptin signalling and although research on these topics are still in their infancy, it is moving at great pace. This review thus aims to bring together the current knowledge on the photic control of reproduction mainly focusing on seasonal temperate fish species and shape the current working hypotheses supported by recent findings obtained in teleosts or based on knowledge gathered in mammalian and avian species. Four of the main potential regulatory systems (light perception, melatonin, clock genes and kisspeptin) in fish reproduction are reviewed.
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Peces/fisiología , Sistemas Neurosecretores/fisiología , Fotoperiodo , Reproducción/fisiología , Animales , Ritmo CircadianoRESUMEN
Photoperiod is perceived by pineal photoreceptors and transduced into rhythmic melatonin signals. These rhythms can be influenced by light intensity and spectral content. In this study we compared the light sensitivity of Atlantic salmon, European sea bass and Atlantic cod by testing ex vivo the effect of different intensities and narrow bandwidth lights on nocturnal melatonin suppression by isolated pineal glands in a flow-through culture system. Using combinations of neutral density and bandpass interference filters we tested a range of light intensities (ranging from 1.22x10(13) to 3.85x10(6) photons s(-1) cm(-2)) and three wavelengths of 80 nm width (472, 555 and 661 nm corresponding to blue, green and red, respectively). Results showed clear species specific light intensity and spectral sensitivities, with cod being from 100 to 1000 times more sensitive than sea bass and salmon. Regarding the influence of spectrum, red light was less efficient on suppressing melatonin than blue and green in salmon but results were not as clear in the two other species studied. Finally, the first evidence of relative photoreception in teleosts was obtained in cod suggesting that the definition of illuminance thresholds (day/night perception) would depend on the day intensity. Indeed, a single order of magnitude increase or decrease in day intensity was shown to elicit a significant shift in the intensity response curve of night-time melatonin suppression. Taken together, this study demonstrated species specific light intensity and spectral sensitivities within temperate teleosts.
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Lubina/metabolismo , Gadus morhua/metabolismo , Luz , Fotoperiodo , Glándula Pineal/metabolismo , Glándula Pineal/efectos de la radiación , Salmo salar/metabolismo , Animales , Regulación de la Expresión Génica/genética , Regulación de la Expresión Génica/fisiología , Melatonina/metabolismo , RadioinmunoensayoRESUMEN
The aim of this study was to compare the circadian control of melatonin production in teleosts. To do so, the effects of ophthalmectomy on circulating melatonin rhythms were studied along with ex vivo pineal culture in six different teleosts. Results strongly suggested that the circadian control of melatonin production could have dramatically changed with at least three different systems being present in teleosts when one considers the photic regulation of pineal melatonin production. First, salmonids presented a decentralized system in which the pineal gland responds directly to light independently of the eyes. Then, in seabass and cod both the eyes and the pineal gland are required to sustain full night-time melatonin production. Finally, a third type of circadian control of melatonin production is proposed in tilapia and catfish in which the pineal gland would not be light sensitive (or only slightly) and required the eyes to perceive light and inhibit melatonin synthesis. Further studies (anatomical, ultrastructural, retinal projections) are needed to confirm these results. Ex vivo experiments indirectly confirmed these results, as while the pineal gland responded normally to day-night rhythms in salmonids, seabass and cod, only very low levels were obtained at night in tilapia and no melatonin could be measured from isolated pineal glands in catfish. Together, these findings suggest that mechanisms involved in the perception of light and the transduction of this signal through the circadian axis has changed in teleosts possibly as a reflection of the photic environment in which they have evolved in.
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Ritmo Circadiano/fisiología , Peces/metabolismo , Melatonina/biosíntesis , Glándula Pineal/metabolismo , Animales , Enucleación del Ojo , Luz , Modelos Biológicos , Estimulación Luminosa , Glándula Pineal/efectos de la radiaciónRESUMEN
The purpose of this study was to determine and compare the light sensitivity of two commercially important, phylogenetically different teleost species in terms of melatonin production. Three series of experiments were performed on both Atlantic salmon and European sea bass. First, a range of light intensities were tested ex vivo on pineal melatonin production in culture during the dark phase. Then, light transmission through the skull was investigated, and finally short-term in vivo light sensitivity trials were performed. Results showed that sea bass pineal gland ex vivo are at least 10 times more sensitive to light than that of the salmon. Light intensity threshold in sea bass appeared to be between 3.8 x 10(-5) and 3.8 x 10(-6) W/m2 in contrast to 3.8 x 10(-4) and 3.8 x 10(-5) W/m2 in salmon. These highlighted species-specific light sensitivities of pineal melatonin production that are likely to be the result of adaptation to particular photic niches. Light transmission results showed that a significantly higher percentage of light penetrates the sea bass pineal window relative to salmon, and confirmed that penetration is directly related to wavelength with higher penetration towards the red end of the visible spectrum. Although results obtained in vivo were comparable, large differences between ex vivo and in vivo were observed in both species. The pineal gland in isolation thus appeared to have different sensitivities as the whole animal, suggesting that retinal and/or deep brain photoreception may contribute, in vivo, to the control of melatonin production.
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Oscuridad , Peces/fisiología , Luz , Melatonina/fisiología , Animales , Ensayo de Inmunoadsorción Enzimática , Especificidad de la EspecieRESUMEN
When the diatom, Phaeodactylum tricornutum, and the microalga, Dunaliella tertiolecta, are cultured together in a chemostat at dilution factors of approximately 0.5 day-1, the diatom develops the higher population density. At dilution factors above 1.2 day-1 the inability of the diatom to assimilate nutrient as fast as it flows into the chemostat results in the microalga generating the larger population. This change in population densities is accompanied by an increase in the chlorophyll content of the diatom and a decrease in the chlorophyll content of the microalga. Two species of phytoplankton can coexist when they compete for nutrient in a chemostat providing they do not otherwise interact. When the species do interact coexistence in a stable steady state is possible providing intraspecies interactions exceed the interactions between the species. Both species adjust their consumption to minimise the concentration of nutrient in the chemostat and their growth is modified to match the dilution factor of the flow.
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Adaptación Fisiológica , Chlorophyta/crecimiento & desarrollo , Diatomeas/crecimiento & desarrollo , Clorofila/metabolismo , Chlorophyta/metabolismo , Técnicas de Cocultivo , Diatomeas/metabolismo , SimbiosisRESUMEN
AIM: To investigate whether 4 weeks of oral supplementation with coenzyme Q10 (CoQ10) would increase its concentration in skeletal muscle, and affect aerobic power (VO2max) and oxygen consumption during submaximal exercise in healthy, physically active men. METHODS: Six volunteers with an average (+/-SD) age of 29.7+/-7.2 years and VO2max of 39.4+/-8.5 mL.kg-1.min-1, participated in a single-blind trial. The experiment consisted of 4 2-week phases, in the order of placebo run-in, CoQ10 supplementation (150 mg daily), CoQ10 (150 mg) plus vitamin E (1,000 IU daily), and placebo wash-out. A three-stage cycle economy test (4 minutes at each of 50, 100, and 150 watts), followed by a VO2max test (25 watts increment every minute till exhaustion), were performed prior to the supplementation and at the end of each phase. Blood samples were taken pre and post each VO2max test, and biopsy samples were obtained from the vastus lateralis muscle pre and post the 4 weeks of CoQ10 supplementation. RESULTS: The plasma CoQ10 concentration was significantly elevated by the supplementation (P<0.05), however, it did not vary significantly pre and post each exercise test (P>0.05). The muscle CoQ10 concentration, VO2max ventilatory threshold, exercise economy and oxygen deficit showed no significant changes in response to the supplementation. CONCLUSION: It was speculated that the non-significant effects of supplementation in healthy, non CoQ10-deficient men could be due to either that the mitochondrial membrane is normally saturated with CoQ10, or that the selected exercise testing protocol and variables were not sensitive enough to detect the effects.