RESUMO
Thermal-stress events associated with climate change cause coral bleaching and mortality that threatens coral reefs globally. Yet coral bleaching patterns vary spatially and temporally. Here we synthesize field observations of coral bleaching at 3351 sites in 81 countries from 1998 to 2017 and use a suite of environmental covariates and temperature metrics to analyze bleaching patterns. Coral bleaching was most common in localities experiencing high intensity and high frequency thermal-stress anomalies. However, coral bleaching was significantly less common in localities with a high variance in sea-surface temperature (SST) anomalies. Geographically, the highest probability of coral bleaching occurred at tropical mid-latitude sites (15-20 degrees north and south of the Equator), despite similar thermal stress levels at equatorial sites. In the last decade, the onset of coral bleaching has occurred at significantly higher SSTs (â¼0.5 °C) than in the previous decade, suggesting that thermally susceptible genotypes may have declined and/or adapted such that the remaining coral populations now have a higher thermal threshold for bleaching.
Assuntos
Adaptação Fisiológica , Antozoários/fisiologia , Mudança Climática , Análise de Variância , Animais , Recifes de Corais , Temperatura Alta , Oceano Índico , Oceano PacíficoRESUMO
This research investigated the reproductive biology (sex ratio, hermaphroditic pattern, size and age at maturity) of Cephalopholis argus, known locally in Hawaii by its Tahitian name roi. The results suggest that C. argus exhibits monandric protogyny (female gonad differentiation with female to male sex change) with females reaching sexual maturity at 1.2 years (95% c.i.: 0.6, 1.6) and 20.0 cm total length (LT ; 95% c.i.: 19.6, 21.2). The female to male sex ratio was 3.9:1. The average age and LT at sex change was 11.5 years (95% c.i.: 11.1, 12.9) and 39.9 cm (95% c.i.: 39.5, 41.2), respectively. Current information on spawning seasonality of this species is incomplete, but based on the occurrence of spawning capable and actively spawning females, spawning probably takes place from May to October. Evidence of lunar spawning periodicity was found, with an increased proportion of spawning capable and actively spawning females, and an increased female gonado-somatic index during first quarter and full-moon phases. This information fills a valuable information gap in Hawaii and across the species' native range.
Assuntos
Bass/fisiologia , Reprodução/fisiologia , Animais , Bass/anatomia & histologia , Feminino , Gônadas/fisiologia , Havaí , Masculino , Lua , Ovário , Processos de Determinação Sexual/fisiologia , Razão de Masculinidade , Maturidade SexualRESUMO
To examine the indirect effects of fishing on energy allocation in non-target prey species, condition and reproductive potential were measured for five representative species (two-spot red snapper Lutjanus bohar, arc-eye hawkfish Paracirrhites arcatus, blackbar devil Plectroglyphidodon dickii, bicolour chromis Chromis margaritifer and whitecheek surgeonfish Acanthurus nigricans) from three reef-fish communities with different levels of fishing and predator abundance in the northern Line Islands, central Pacific Ocean. Predator abundance differed by five to seven-fold among islands, and despite no clear differences in prey abundance, differences in prey condition and reproductive potential among islands were found. Body condition (mean body mass adjusted for length) was consistently lower at sites with higher predator abundance for three of the four prey species. Mean liver mass (adjusted for total body mass), an indicator of energy reserves, was also lower at sites with higher predator abundance for three of the prey species and the predator. Trends in reproductive potential were less clear. Mean gonad mass (adjusted for total body mass) was high where predator abundance was high for only one of the three species in which it was measured. Evidence of consistently low prey body condition and energy reserves in a diverse suite of species at reefs with high predator abundance suggests that fishing may indirectly affect non-target prey-fish populations through changes in predation and predation risk.
Assuntos
Recifes de Corais , Peixes/fisiologia , Cadeia Alimentar , Animais , Pesqueiros , Peixes/anatomia & histologia , Gônadas/anatomia & histologia , Fígado/anatomia & histologia , Tamanho do Órgão , Ilhas do Pacífico , Densidade Demográfica , Dinâmica Populacional , Comportamento Predatório , ReproduçãoRESUMO
Nutrient uptakes and metabolite production by equine morula and blastocyst stage embryos were determined by non-invasive microfluorometry. Equine morula took up equal amounts of both pyruvate and glucose. However, at the early blastocyst there was a small increase in glucose uptake and, by the expanded blastocyst stage, glucose was the predominant nutrient. Expanded blastocysts took up five times more glucose than pyruvate. Expanded blastocysts exhibited an exponential increase in glucose uptake and lactate production with respect to both diameter and surface area. As less than 50% of the glucose was accounted for by lactate production, the equine blastocyst appears to have a significant capacity to oxidize glucose. Embryos with a higher morphological grade consumed more nutrients than those with a poorer morphology. However, there was a large range in nutrient consumption within the highest grade blastocysts. This suggests that nutrient uptake may be useful as a viability marker of equine blastocysts.
Assuntos
Blastocisto/metabolismo , Glucose/metabolismo , Cavalos/embriologia , Mórula/metabolismo , Animais , Blastocisto/citologia , Tamanho Celular , Citofotometria , Feminino , Cavalos/metabolismo , Ácido Láctico/metabolismo , Mórula/citologia , Ácido Pirúvico/metabolismoRESUMO
Cryopreservation of equine embryos with conventional slow-cooling procedures has proven challenging. An alternative approach is vitrification, which can minimize chilling injuries by increasing the rates of cooling and warming. The open pulled straw (OPS) and cryoloop have been used for very rapid cooling and warming rates. The objective of this experiment was to compare efficacy of vitrification of embryos in OPS and the cryoloop to conventional slow cool procedures using 0.25 mL straws. Grade 1 or 2 morulae and early blastocysts (< or = 300 microm in diameter) were recovered from mares on Day 6 or 7 post ovulation. Twenty-seven embryos were assigned to three cryopreservation treatments: (1) conventional slow cooling (0.5 degrees C/min) with 1.8 M ethylene glycol (EG) and 0.1 M sucrose, (4) vitrification in OPS in 16.5% EG, 16.5% DMSO and 0.5 M sucrose, or (3) vitrification with a cryoloop in 17.5% EG, 17.5% DMSO, 1 M sucrose and 0.25 microM ficoll. Embryos were evaluated for size and morphological quality (Grade 1 to 4) before freezing, after thawing, and after culture for 20 h. In addition, propidium iodide (PI) and Hoechst 33342 staining were used to assess percent live cells after culture. There were no differences (P > 0.1) in morphological grade or percent live cells among methods. Mean grades for embryos after culture were 2.9 +/- 0.2, 3.1 +/- 0.1, and 3.3 +/- 0.2 for conventional slow cooling, OPS and cryoloop methods, respectively. Embryo grade and percent live cells were correlated, r = 0.66 (P < 0.004). Thus OPS and the cryoloop were similarly effective to conventional slow-cooling procedures for cryopreserving small equine embryos.
Assuntos
Criopreservação/veterinária , Cavalos/embriologia , Animais , Benzimidazóis/química , Criopreservação/métodos , Feminino , Corantes Fluorescentes/química , Cavalos/fisiologia , Inseminação Artificial/veterinária , Masculino , Microscopia de Fluorescência/veterinária , Gravidez , Propídio/químicaRESUMO
In the past, there has been no consistent, objective method of following patients undergoing botulinum toxin injections for treatment of laryngeal dystonia. Herein, the application of translaryngeal resistance measurements to 15 dysphonic patients is described. Laryngeal resistance is calculated from analysis of translaryngeal pressure and airflow during the utterance /pi/, and found to fall predictably after successful toxin injection. In our series of patients, laryngeal resistance dropped by 69.1% after initial toxin injection. The changes in resistance over time correlate with subjective impressions of voice quality. Translaryngeal resistance measurements can be used objectively to follow patients longitudinally after injection and to collect objective data for analysis. No previously described measurements have met all these criteria. Laryngeal resistance measurement is an ideal method of documenting the results of botulinum toxin injection for the treatment of focal laryngeal dystonia.
Assuntos
Toxinas Botulínicas/uso terapêutico , Músculos Laríngeos/fisiopatologia , Laringismo/terapia , Prega Vocal/fisiopatologia , Distúrbios da Voz/terapia , Resistência das Vias Respiratórias/fisiologia , Feminino , Seguimentos , Humanos , Laringismo/epidemiologia , Laringismo/fisiopatologia , Masculino , Pessoa de Meia-Idade , Ventilação Pulmonar/fisiologia , Fatores de Tempo , Distúrbios da Voz/epidemiologia , Distúrbios da Voz/fisiopatologia , Qualidade da VozRESUMO
BACKGROUND: Vitamin B12 deficiency may result in a number of neurological and neuropsychiatric disorders. Patients with human immunodeficiency virus type 1 (HIV-1) infection may have a high rate of vitamin B12 deficiency and nervous system disease. Vitamin B12 deficiency may contribute to neurological disease in HIV-1-infected individuals. OBJECTIVE: To evaluate the possible contribution of vitamin B12 deficiency to neurological disease in HIV-1-infected individuals. MAIN OUTCOME MEASURES: Comparison of serum vitamin B12 levels with neurological, neuropsychological, and mood state abnormalities in 153 HIV-1-positive subjects and 57 high-risk seronegative controls. A subgroup of 67 subjects underwent additional extensive clinical neurophysiological, cerebrospinal fluid, and magnetic resonance imaging evaluations. RESULTS: No statistically significant relationships were noted between vitamin B12 levels and abnormalities on any of the measures examined. CONCLUSIONS: This study does not indicate an important role for vitamin B12 deficiency in the neurological disease of HIV-1 infection.
Assuntos
Infecções por HIV/complicações , HIV-1 , Doenças do Sistema Nervoso/etiologia , Deficiência de Vitamina B 12/etiologia , Adulto , Feminino , Infecções por HIV/fisiopatologia , Infecções por HIV/psicologia , Humanos , Masculino , Doenças do Sistema Nervoso/fisiopatologia , Doenças do Sistema Nervoso/psicologia , Testes Neuropsicológicos , Vitamina B 12/sangue , Deficiência de Vitamina B 12/fisiopatologia , Deficiência de Vitamina B 12/psicologiaRESUMO
The diagnosis of postinfectious encephalomyelitis with symmetric lesions in the basal ganglia was confirmed by magnetic resonance imaging in 2 patients. A 7-year-old patient experienced severe dystonia and hyperreflexia; magnetic resonance imaging demonstrated bilateral lesions in the putamina and basis pontes. The other patient, a 2-year-old female, manifested hypotonia, facial grimacing, and athetosis. Symmetric lesions in the globus pallidus and substantia nigra were demonstrated by imaging studies. The nature and monophasic course of illness in these 2 patients, as well as the symmetric involvement of specific regions of the basal ganglia, may result from an immune-mediated postinfectious demyelinating process.
Assuntos
Gânglios da Base/diagnóstico por imagem , Encefalomielite/diagnóstico por imagem , Infecções , Gânglios da Base/patologia , Criança , Encefalomielite/diagnóstico , Encefalomielite/etiologia , Feminino , Globo Pálido/diagnóstico por imagem , Globo Pálido/patologia , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Putamen/diagnóstico por imagem , Putamen/patologia , Substância Negra/diagnóstico por imagem , Substância Negra/patologia , Tomografia Computadorizada por Raios XRESUMO
The double-labeling, fluorescent dye technique was used in order to demonstrate the extent to which the central processes of renal afferent neurons directly project to the brainstem. One injection of a fluorescent dye was placed in the cortex of the left kidney of male rats, and a second injection of a different dye was placed into the lower medulla. The results demonstrate that some of the renal afferents directly project to the medulla but not to higher regions of the brain. A total of approximately 8% of renal afferents were typically shown to have direct projections.
Assuntos
Tronco Encefálico/anatomia & histologia , Córtex Renal/inervação , Medula Espinal/anatomia & histologia , Vias Aferentes/anatomia & histologia , Animais , Mapeamento Encefálico , Masculino , RatosRESUMO
The neuronal cell bodies of the afferent fibers innervating the urinary system and the adrenal gland were identified utilizing the method of the retrograde transport of the fluorescent dyes, fast blue and nuclear yellow. Fast blue was injected into the bladder, left ureter, or left adrenal gland, and nuclear yellow was injected into the left kidney of the same animal. The results demonstrate that each organ receives a discrete sensory innervation and that none of the sensory neurons innervating the organs have collateral inputs to the kidney. The location of the DRG cell bodies indicates that more caudally placed organs are innervated by more caudally placed DRG. These findings confirm previous localization studies of the kidney afferents, and support the effectiveness of the use of the fluorescent dye method to localize peripheral afferent cell bodies.
Assuntos
Glândulas Suprarrenais/inervação , Nervos Espinhais/anatomia & histologia , Sistema Urinário/inervação , Animais , Corantes Fluorescentes , Gânglios Espinais/anatomia & histologia , Rim/inervação , Masculino , Neurônios Aferentes , Ratos , Ureter/inervação , Bexiga Urinária/inervaçãoRESUMO
The location of cell bodies of renal sensory neurons was studied. Small injections of a fluorescent dye (True Blue or Fast Blue) were placed into either the right or left kidney of male or female rats. Whereas no differences were detected in the labeling patterns of males vs females, right kidney injections did label slightly higher dorsal root ganglia than left injections. In all cases the labeling was confined to the T6-L2 ganglia ipsilateral to the injection.
Assuntos
Gânglios Espinais/anatomia & histologia , Rim/inervação , Animais , Feminino , Corantes Fluorescentes , Gânglios Espinais/citologia , Rim/citologia , Masculino , Microscopia de Fluorescência , Neurônios Aferentes/citologia , Ratos , Ratos EndogâmicosRESUMO
The present study has used the fluorescent dye tracing technique in order to determine the exact location of neuronal somata within the subicular cortex which project to the diencephalon, telencephalon (entorhinal cortex), or to both via axonal collaterals. The greatest collateralization to the two sites is found in the neurons of the subiculum proper. In this region approximately one-third of all neurons project to both the entorhinal cortex and the hypothalamus (either the mammillary bodies or the ventral medial hypothalamic nucleus). The hypothalamic and cortical projection cell bodies in this region are intermingled extensively with each other. In the cytoarchitectonically more organized regions of the subicular cortex, i.e. the pre-, para- and postsubiculum, the situation is quite different. In these areas neurons project to the hypothalamus or entorhinal cortex but very seldom does a single neuron project to both areas, and the neuronal somata are spatially segregated according to their projections. The entorhinal cortex projecting somata are located in layer two whereas the hypothalamic neurons are in the deeper layer. The somata projecting to the thalamus are the most deeply located neurons in all regions of the subicular cortex, and extremely few collateralize to the entorhinal cortex.
Assuntos
Axônios/ultraestrutura , Córtex Cerebral/anatomia & histologia , Hipotálamo/anatomia & histologia , Sistema Límbico/anatomia & histologia , Animais , Dominância Cerebral/fisiologia , Vias Eferentes/anatomia & histologia , Hipocampo/anatomia & histologia , Masculino , Corpos Mamilares/anatomia & histologia , Microscopia de Fluorescência , Muridae , Neurônios/ultraestrutura , Núcleos Talâmicos/anatomia & histologia , Núcleo Hipotalâmico Ventromedial/anatomia & histologiaRESUMO
Retinoic acid-binding protein (RABP) has been detected in the nuclei of chick embryo skin and Lewis lung tumor. The nuclear binding component showed the same ligand specificity and sedimentation value as the cytosol RABP. Whereas pronase completely digested the nuclear binding component, DNase showed 40%, and RNase showed negligible digestive action. Retinoic acid binding to the nuclear RABP was completely inhibited by a mercurial, and the inhibition was reversed by dithiothreitol. The nonspecific uptake of retinoic acid by Lewis drug nuclei and chick embryo skin nuclei was inhibited up to 50% by cytosol RABP. The maximal inhibitory effect produced by cytosol RABP was after 45-min incubation. Incubation of Lewis lung tumor with [3H]retinoic acid resulted in the appearance of nuclear RABP: [3H]retinoic acid in the nuclei. The complex formed was weak, and most of the bound retinoic acid could be removed by dialysis.