Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 837
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Prog Oceanogr ; 160: 186-212, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30573929

RESUMO

Ocean color measured from satellites provides daily global, synoptic views of spectral waterleaving reflectances that can be used to generate estimates of marine inherent optical properties (IOPs). These reflectances, namely the ratio of spectral upwelled radiances to spectral downwelled irradiances, describe the light exiting a water mass that defines its color. IOPs are the spectral absorption and scattering characteristics of ocean water and its dissolved and particulate constituents. Because of their dependence on the concentration and composition of marine constituents, IOPs can be used to describe the contents of the upper ocean mixed layer. This information is critical to further our scientific understanding of biogeochemical oceanic processes, such as organic carbon production and export, phytoplankton dynamics, and responses to climatic disturbances. Given their importance, the international ocean color community has invested significant effort in improving the quality of satellite-derived IOP products, both regionally and globally. Recognizing the current influx of data products into the community and the need to improve current algorithms in anticipation of new satellite instruments (e.g., the global, hyperspectral spectroradiometer of the NASA Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission), we present a synopsis of the current state of the art in the retrieval of these core optical properties. Contemporary approaches for obtaining IOPs from satellite ocean color are reviewed and, for clarity, separated based their inversion methodology or the type of IOPs sought. Summaries of known uncertainties associated with each approach are provided, as well as common performance metrics used to evaluate them. We discuss current knowledge gaps and make recommendations for future investment for upcoming missions whose instrument characteristics diverge sufficiently from heritage and existing sensors to warrant reassessing current approaches.

2.
J Clin Pharm Ther ; 42(3): 350-355, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28370067

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Neurotoxicity is a side effect of acyclovir. We report the first case, to our knowledge, whereby Bayesian-informed clearance estimates supported a therapeutic intervention for acyclovir-associated neurotoxicity. CASE SUMMARY: A 62-year-old male with the diagnosis of disseminated zoster was being treated with intravenous (IV) acyclovir when he developed symptoms of acute neurotoxicity. Acyclovir had been dose-adjusted for renal dysfunction according to traditional creatinine clearance estimates; however, as the patient was also on vancomycin, Bayesian estimates of vancomycin clearances were performed, which revealed a 2-fold lower creatinine clearance. In response to the Bayesian estimates, acyclovir was discontinued, and improvements in mentation were noted within 24 hours. WHAT IS NEW AND CONCLUSION: Alternate approaches to estimate renal function beyond Cockcroft-Gault, such as a Bayesian approach used in our patient, should be considered when population estimates are likely to be inaccurate and potentially dangerous to the patient.


Assuntos
Aciclovir/efeitos adversos , Antivirais/efeitos adversos , Síndromes Neurotóxicas/etiologia , Aciclovir/administração & dosagem , Antivirais/administração & dosagem , Teorema de Bayes , Creatinina/análise , Relação Dose-Resposta a Droga , Herpes Zoster/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Neurotóxicas/diagnóstico , Vancomicina/administração & dosagem , Vancomicina/farmacocinética
3.
J Appl Anim Welf Sci ; 26(4): 565-581, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35037536

RESUMO

Free-roaming dogs (FRD) represent a large proportion of the canine population in India and are often implicated as a source of conflict with humans. However, objective data on the attitudes and perceptions of local communities toward FRD are lacking. This study collected baseline data from 1141 households in Goa, India, on FRD feeding practices and assessed people's attitudes toward FRD in urban and rural communities. Additionally, respondents identified problems caused by FRD and proposed potential solutions.The study reported that 37% of respondents fed FRD with dog owners and Hindus being the most likely to feed. The majority of respondents agreed FRD were a menace (57%), a nuisance (58%) and scary (60%). Most respondents also agreed FRD were a vulnerable population (59%), that belong in communities (66%) and have a right to live on the streets (53%). Barking was the most commonly reported problem associated with FRD and the preferred solution was to impound FRD in shelters. This study reveals the complex and often misunderstood relationship between local communities and FRD and highlights potential strategies to reduce human-dog conflict.

4.
Indian J Exp Biol ; 50(1): 7-18, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22279935

RESUMO

Thyroid-related hormones regulate the efficiency and expression of sarco-endoplasmic reticulum calcium ATPases in cardiac and skeletal muscle. However, little is known about the relationship between thyroid hormones and calcium (Ca2+) homeostasis in the brain. It is hypothesized that manipulating rat thyroid hormone levels would induce significant brain Ca2+ adaptations consistent with clinical findings. Adult male Sprague-Dawley rats were assigned to one of three treatment groups for 28 days: control, hypothyroid (6-n-propyl-2-thiouracil (PTU), an inhibitor of thyroxine (T4) synthesis), and hyperthyroid (T4). Throughout, rats were given weekly behavioral tests. Ca2+ accumulation decreased in the cerebellum in both hyper- and hypothyroid animals. This was specific to different ER pools of calcium with regional heterogeneity in the response to thyroid hormone manipulation. Behavioral tasks demonstrated sensitivity to thyroid manipulation, and corresponded to alterations in calcium homeostasis. Ca2+ accumulation heterogeneity in chronic hyper- and hypothyroid animals potentially explains clinical manifestations of altered thyroid status.


Assuntos
Encéfalo/efeitos dos fármacos , Cálcio/metabolismo , Cerebelo/efeitos dos fármacos , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Tireoide (USP)/farmacologia , Hormônios Tireóideos/farmacologia , Animais , Comportamento Animal , Western Blotting , Encéfalo/citologia , Encéfalo/metabolismo , Cerebelo/citologia , Cerebelo/metabolismo , Homeostase , Hipertireoidismo/induzido quimicamente , Hipertireoidismo/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microssomos/efeitos dos fármacos , Microssomos/metabolismo , Ratos , Ratos Sprague-Dawley , Tiroxina/toxicidade , Tri-Iodotironina/farmacologia
5.
Osteoporos Int ; 22(10): 2623-31, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21161644

RESUMO

UNLABELLED: Despite advances in prevention, fall-related hospitalisation rates among older people are still increasing. Rates between 1998/1999 and 2008/2009 for non-facture-related injuries increased by 6.1% while fracture injuries declined by -0.4%. Varying trends in rates of different injury types makes it difficult to provide a definitive explanation for these changes. INTRODUCTION: Despite advances in fall prevention research and practice, the rate of fall-related hospitalisations continues to increase. However, hip fracture rates appear to be declining. An examination of trends in types of injuries that contribute to the overall fall injury rate is required to establish which injuries are driving the falls admission rate. The aim of this paper is to examine trends in fall-related injury hospital admissions by injury type in New South Wales (NSW), Australia. METHODS: A retrospective review of fall-related injury hospitalisations in NSW among individuals aged 65+ years, by injury type, was conducted from 1 July 1998 to 30 June 2009. Direct age-standardised admission rates were calculated. Negative binomial regression was used to examine the statistical significance of changes in trend over time of different hospitalised fall-related injuries. RESULTS: The fall-related hospitalisation rate increased by 1.7% each year (p < 0.0001; 95% confidence interval (CI), 1.3-2.1%). However, the rate of fracture declined by -0.4% (p < 0.03; 95% CI, -0.8-0.0%); whereas, the non-fracture rate increased by 6.1% (p < 0.0001; 95% CI, 5.5-6.7%) annually. Rates for severe head injuries, rib and pelvic fracture increased while those for hip and forearm fracture declined. CONCLUSIONS: It appears that while fall prevention efforts in NSW are not yet affecting the overall rate of injury hospitalisation, there has been a significant decline in the rates of some fractures. Opposing trends in the rates of other fracture admissions and a significant increase in the rate of non-fracture injuries associated with falls makes a definitive explanation for these changes difficult.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Fraturas Ósseas/epidemiologia , Hospitalização/tendências , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , New South Wales/epidemiologia , Estudos Retrospectivos , Ferimentos e Lesões/epidemiologia
6.
Integr Org Biol ; 3(1): obab015, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34337322

RESUMO

A number of nudibranchs, including Melibe engeli and Melibe pilosa, harbor symbiotic photosynthetic zooxanthellae. Melibe leonina spends most of its adult life on seagrass or kelp, capturing planktonic organisms in the water column with a large, tentacle-lined oral hood that brings food to its mouth. M. leonina also has an extensive network of digestive diverticula, located just beneath its translucent integument, that are typically filled with pigmented material likely derived from ingested food. Therefore, the focus of this project was to test the hypothesis that M. leonina accumulates symbiotic photosynthetic dinoflagellates in these diverticula. First, we conducted experiments to determine if M. leonina exhibits a preference for light, which would allow chloroplasts that it might be harboring to carry out photosynthesis. We found that most M. leonina preferred shaded areas and spent less time in direct sunlight. Second, we examined the small green circular structures in cells lining the digestive diverticula. Like chlorophyll, they exhibited autofluorescence when illuminated at 480 nm, and they were also about the same size as chloroplasts and symbiotic zooxanthellae. However, subsequent electron microscopy found no evidence of chloroplasts in the digestive diverticula of M. leonina; the structures exhibiting autofluorescence at 480 nm were most likely heterolysosomes, consistent with normal molluscan digestion. Third, we did not find evidence of altered oxygen consumption or production in M. leonina housed in different light conditions, suggesting the lack of any significant photosynthetic activity in sunlight. Fourth, we examined the contents of the diverticula, using HPLC, thin layer chromatography, and spectroscopy. The results of these studies indicate that the diverticula did not contain any chlorophyll, but rather harbored other pigments, such as astaxanthin, which likely came from crustaceans in their diet. Together, all of these data suggest that M. leonina does sequester pigments from its diet, but not for the purpose of symbiosis with photosynthetic zooxanthellae. Considering the translucent skin of M. leonina, the pigmented diverticula may instead provide camouflage.


Varios nudibranquios, incluidos Melibe engeli y Melibe pilosa, albergan zooxantelas fotosintéticas simbióticas. Melibe leonina pasa la mayoría de su vida adulta en pastos marinos o quelpo, donde captura organismos planctónicos en la columna de agua con una gran capucha oral forrada por tentáculos que llevan comida a su boca. Melibe leonina también tiene una extensa red de divertículos digestivos, ubicados justo debajo de su tegumento translúcido, que generalmente están llenos de material pigmentado probablemente derivado de alimentos ingeridos. Por lo tanto, el objetivo de este proyecto fue evaluar la hipótesis de que M. leonina acumula dinoflagelados fotosintéticos simbióticos en estos divertículos. Primero, realizamos experimentos para determinar si M. leonina se orienta hacia la luz, lo cual permitiría a los cloroplastos que podría albergar el realizar la fotosíntesis. Descubrimos que la mayoría de M. leonina prefería las áreas sombreadas y pasaba menos tiempo bajo la luz solar directa. En segundo lugar, examinamos las pequeñas estructuras circulares verdes en las células que recubren los divertículos digestivos. Al igual que la clorofila, exhibieron autofluorescencia cuando se iluminaban a 480 nm, y también tenían aproximadamente el mismo tamaño que los cloroplastos y las zooxantelas simbióticas. No obstante, la microscopía electrónica no produjo evidencia de cloroplastos en los divertículos digestivos de M. leonina. Es probable que las estructuras que exhibieron autofluorescencia en 480 nm fuesen heterolisosomas, lo cual es consistente con la digestión normal de moluscos. En tercer lugar, no encontramos evidencia de un consumo o producción de oxígeno alterado en M. leonina alojadas varias condiciones lumínicas, lo cual sugiere la ausencia de actividad fotosintética significativa en la presencia de luz solar. En cuarto lugar, examinamos el contenido de los divertículos mediante HPLC, cromatografía en capa fina, y espectroscopia. Los resultados de estos estudios indican que los divertículos no contenían clorofila, pero si otros pigmentos como la astaxantina que probablemente provenía de crustáceos en su dieta. Nuestros datos sugieren que M. leonina secuestra pigmentos de su dieta, pero no con el propósito de la simbiosis con zooxantelas fotosintéticas. Teniendo en cuenta la piel translúcida de M. leonina, los divertículos pigmentados podrían quizás proporcionar camuflaje.

7.
J Exp Med ; 162(6): 1878-91, 1985 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-3934318

RESUMO

Analysis of the IgG autoantibody subclass response in the collagen II autoimmune arthritis (CII AIA)-susceptible D1 strain mice revealed that the onset of disease was associated with a predominance of IgG2a autoantibody. In a comparative study, resistance in the B6 strain was associated with a deficient IgG2a autoantibody response. B6 IgG1, 2b, and 3 autoantibody responses generally overlapped those of arthritic D1 mice, and estimates of antibody crossreactivity and affinity were similar for both strains. In crosses between D1 and B6, arthritis developed only in those F1 mice with IgG2a autoantibody responses approximating or exceeding those in arthritic D1 mice. Additional studies with B6 and B10 strains suggested an alternate role for the IgG2b autoantibody response. In inbred strains with known genetic backgrounds, a dissociation between the magnitude of the total IgG autoantibody response and the percent of total as IgG2a was demonstrated. The H-2q, Ig-1c D1 strain was a high-total and high-percent IgG2a responder, while the H-2d, Ig-1c D2 strain was a low-total but high-percent IgG2a responder. The H-2b, Ig-1b B6 strain was a low-total and low-percent IgG2a responder, while the H-2b/q, Ig-1b/c (B6D1)F1 hybrid was a low-total but high-percent IgG2a responder. A further dissociation between high-percent IgG2a autoantibody responsiveness and the H-2 haplotype was demonstrated by the H-2 congenic B10.D2/n (H-2d, Ig-1b) strain, in which a low-percent IgG2a response was observed to differ from the D2 strain. High-percent IgG2a autoantibody responsiveness also appeared to be inherited as a dominant trait based upon high responses in all (B6D1)F1 hybrids and backcrosses to D1. These findings suggest that the H-2 haplotype is involved in the total IgG autoantibody response but that the relative fraction of the total response as IgG2a is independent of the H-2 haplotype and possibly related to Igh-C genes. C5-deficient SWR (H-2q, Ig-1c) mice were found to have a high total autoantibody response to mouse CII and IgG2a comparable to arthritic D1 mice, but these mice did not develop arthritis. Based upon these observations, we conclude that susceptibility to CII AIA requires the interaction of multiple genes, both major histocompatibility complex (MHC) and non-MHC, which influence the magnitude (total IgG) and the quality (IgG subclass) of the autoimmune response and the availability of appropriate mediators (C5) to initiate the inflammatory reaction.


Assuntos
Artrite Experimental/genética , Artrite/genética , Doenças Autoimunes/genética , Colágeno/imunologia , Genes MHC da Classe II , Imunoglobulina G/imunologia , Animais , Afinidade de Anticorpos , Artrite Experimental/imunologia , Autoanticorpos/biossíntese , Doenças Autoimunes/imunologia , Complemento C5/genética , Complemento C5/imunologia , Reações Cruzadas , Cruzamentos Genéticos , Ensaio de Imunoadsorção Enzimática , Feminino , Antígenos H-2/genética , Haploidia , Imunidade Inata , Imunoglobulina G/análise , Imunoglobulina G/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Especificidade da Espécie
8.
J Exp Med ; 172(5): 1331-9, 1990 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-1700052

RESUMO

Collagen arthritis (CA), an autoimmune model of rheumatoid arthritis (RA), has been studied in various animals. However, it has not been studied in an animal with a genetic background relevant to RA. We selected rats from a diabetic-resistant (DR) subline of the diabetic BB rat because they have an autoimmune disease-prone background, but not the immunodeficiencies of the diabetic BB rat, and the third hypervariable region (HVRIII) of the BB RT1.D beta gene appeared to encode a nucleotide sequence of the human HLA DR beta gene, which has been reported to be associated with susceptibility to RA. We synthesized oligonucleotide primers flanking the RT1.D beta HVRIII, cloned polymerase chain reaction-amplified DNA into M13mp18, and confirmed the presence of the susceptibility sequence (SS) (RRRAA) by the dideoxy sequencing method in a colony of DR BB/Wor-UTM rats. When immunized with human type II collagen (CII) in incomplete Freunds adjuvant (IFA), arthritis developed rapidly by day 10 with 100% incidence. Light and electron microscopy revealed an unusually severe and aggressive, bidirectional pattern of cartilage resorption by synovial and subchondral mononuclear and multinucleated inflammatory cells. These findings coincided with a predominant humoral response to the cyanogen bromide (CB) 11 fragment of the human CII molecule by the pathogenic IgG2a isotype. This study provides further support to the role of CA as a relevant RA model, the specific roles of the CB11 fragment as a major site of arthritogenic epitopes, and of antibody mechanisms in the pathogenesis of CA. Furthermore, the identification of an RA SS in an immune response gene of the DR BB rat presents a novel opportunity to determine with an animal model the role of other antigens as well as this SS in RA.


Assuntos
DNA/genética , Variação Genética/genética , Antígenos HLA-DR/genética , Região Variável de Imunoglobulina/genética , Ratos Endogâmicos BB/genética , Homologia de Sequência do Ácido Nucleico , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos/imunologia , Artrite Reumatoide/epidemiologia , Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Colágeno/imunologia , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/imunologia , Modelos Animais de Doenças , Suscetibilidade a Doenças , Epitopos/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Imunidade Celular/genética , Imunidade Celular/imunologia , Imunidade Celular/fisiologia , Imunidade Inata/genética , Imunidade Inata/imunologia , Incidência , Dados de Sequência Molecular , Ratos
9.
Integr Org Biol ; 2(1): obaa016, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33791559

RESUMO

The neuropeptide small cardioactive peptide (SCP) plays an integrative role in exciting various motor programs involved in feeding and locomotion in a number of gastropod species. In this study, immunohistochemistry, using monoclonal antibodies against SCPB, was used to localize SCPB-like-immunoreactive neurons in the central nervous system, and map their connections to various tissues, in the nudibranch, Melibe leonina. Approximately 28-36 SCPB-like-immunoreactive neurons were identified in the M. leonina brain, as well as one large neuron in each of the buccal ganglia. The neuropil of the pedal ganglia contained the most SCPB-like-immunoreactive varicosities, although only a small portion of these were due to SCPB-like-immunoreactive neurons in the same ganglion. This suggests that much of the SCPB-like immunoreactivity in the neuropil of the pedal ganglia was from neurons in other ganglia that projected through the pedal-pedal connectives or the connectives from the cerebral and pleural ganglia. We also observed extensive SCPB innervation along the length of the esophagus. Therefore, we investigated the impact of SCPB on locomotion in intact animals, as well as peristaltic contractions of the isolated esophagus. Injection of intact animals with SCPB at night led to a significant increase in crawling and swimming, compared to control animals injected with saline. Furthermore, perfusion of isolated brains with SCPB initiated expression of the swim motor program. Application of SCPB to the isolated quiescent esophagus initiated rhythmic peristaltic contractions, and this occurred in preparations both with and without the buccal ganglia being attached. All these data, taken together, suggest that SCPB could be released at night to arouse animals and enhance the expression of both feeding and swimming motor programs in M. leonina.


El neuropéptido pequeño péptido cardioactivo (SCP) juega un rol integrativo en inducir varios programas motores involucrados en la alimentación y locomoción de varias especies de gasterópodos. En este estudio se usó inmunohistoquímica con anticuerpos contra SCPB para localizar y describir la conectividad de neuronas con inmunoreacción semejante al SCPB en el sistema nervioso central del nudibranquio Melibe leonina. Identificamos entre 28 y 36 neuronas en el cerebro de M. leonina con inmunoreacción semejantes al SCPB, además de una neurona grande en cada ganglio bucal. El neuropilo del ganglio pedal contiene la mayor cantidad de varicosidades neuronales con inmunoreacción semejante al SCPB aunque sólo una fracción pequeña de éstas provenían de neuronas en el mismo ganglio. Esto sugiere que gran parte de la inmunoreacción semejante al SCPB en el neuropilo del ganglio pedal tienen su origen en neuronas en otros ganglios que enviaron sus proyecciones a través de los conectivos entre los ganglios pedales, o provenientes de los ganglios cerebral o pleural. Observamos además extensa inervación con immunoreacción semejante al SCPB a lo largo del esófago. Por lo tanto investigamos el impacto de SCPB en la locomoción de animales intactos, así también como las contracciones peristálticas en preparaciones de esófagos aislados. Inyecciones nocturnas de SCPB en animales intactos resultó en in incremento significante en rastreo y nado comparado con animales inyectados con soluciones salinas. Más aún, perfusión de cerebros aislados con SCPB inició programas de programas motores de nado. La aplicación de SCPB a preparaciones aisladas de esófagos inactivos inició contracciones peristálticas rítmicas, lo cual ocurrió igualmente en preparaciones con conexiones con el ganglio bucal presentes o ausentes. Tomados en conjunto, nuestros datos sugieren que SCPB podría ser liberado de forma nocturna para despertar los animales y aumentar la expresión de programas motores de alimentación y locomoción en M. leonina.

10.
Earth Syst Sci Data ; 12(2): 1123-1139, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-36419961

RESUMO

Light emerging from natural water bodies and measured by radiometers contains information about the local type and concentrations of phytoplankton, non-algal particles and colored dissolved organic matter in the underlying waters. An increase in spectral resolution in forthcoming satellite and airborne remote sensing missions is expected to lead to new or improved capabilities for characterizing aquatic ecosystems. Such upcoming missions include NASA's Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission; the NASA Surface Biology and Geology designated observable mission; and NASA Airborne Visible/Infrared Imaging Spectrometer - Next Generation (AVIRIS-NG) airborne missions. In anticipation of these missions, we present an organized dataset of geographically diverse, quality-controlled, high spectral resolution inherent and apparent optical property (IOP-AOP) aquatic data. The data are intended to be of use to increase our understanding of aquatic optical properties, to develop aquatic remote sensing data product algorithms, and to perform calibration and validation activities for forthcoming aquatic-focused imaging spectrometry missions. The dataset is comprised of contributions from several investigators and investigating teams collected over a range of geographic areas and water types, including inland waters, estuaries, and oceans. Specific in situ measurements include remote-sensing reflectance, irradiance reflectance, and coefficients describing particulate absorption, particulate attenuation, non-algal particulate absorption, colored dissolved organic matter absorption, phytoplankton absorption, total absorption, total attenuation, particulate backscattering, and total backscattering. The dataset can be downloaded from https://doi.org/10.1594/PANGAEA.902230 (Casey et al., 2019).

11.
Science ; 241(4874): 1807-10, 1988 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-2845573

RESUMO

Inherited myoclonus of Poll Hereford calves is characterized by hyperesthesia and myoclonic jerks of the skeletal musculature, which occur spontaneously and in response to sensory stimuli. The disease shows autosomal recessive inheritance, and significant proportions of the Poll Hereford herds in many countries are thought to be carriers of the mutant gene. Studies revealed a specific and marked (90 to 95 percent) deficit in [3H]strychnine binding sites in spinal cord membranes from myoclonic animals compared to controls, reflecting a loss of, or defect in, glycine/strychnine receptors. Spinal cord synaptosomes prepared from affected animals showed a significantly increased ability to accumulate [3H]glycine, indicating an increased capacity of the high-affinity neuronal uptake system for glycine. In contrast, stimulus-induced glycine release and spinal cord glycine concentrations were unaltered.


Assuntos
Mioclonia/veterinária , Receptores de Neurotransmissores/deficiência , Medula Espinal/fisiopatologia , Aminoácidos/metabolismo , Animais , Bovinos , Doenças dos Bovinos/genética , Doenças dos Bovinos/fisiopatologia , Mioclonia/genética , Mioclonia/fisiopatologia , Receptores de Glicina
12.
Ultrasound Obstet Gynecol ; 34(6): 720-3, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19725093

RESUMO

OBJECTIVE: To develop an in-utero stent placement training model. METHODS: The in-utero stent task trainer was constructed using a formalin-preserved gravid pig uterus. Altering the size of the uterine segment, changing the fluid level in the uterus and addition of a large Ziploc freezer bag variably filled with differing amounts of ultrasound gel can vary the procedural skill required. RESULTS: Thoracoamniotic and vesicoamniotic shunts can be simulated using this life-like model. The cost of eight to 10 learning stations is approximately US $ 60. Fetal position, maternal size and amniotic fluid status can be altered rapidly to increase the complexity of the procedure. CONCLUSIONS: This low-cost and realistic task trainer can provide the opportunity to practice in-utero shunt procedures in a non-clinical environment. This model should enhance learning and reinforce acquired skills.


Assuntos
Hidrotórax/cirurgia , Obstetrícia/educação , Stents , Obstrução do Colo da Bexiga Urinária/cirurgia , Animais , Competência Clínica , Feminino , Hidrotórax/diagnóstico por imagem , Hidrotórax/embriologia , Modelos Animais , Obstetrícia/economia , Obstetrícia/instrumentação , Suínos , Ultrassonografia , Obstrução do Colo da Bexiga Urinária/diagnóstico por imagem
13.
Front Mar Sci ; 4: 236, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29291196

RESUMO

Using a global ocean biogeochemical model combined with a forecast of physical oceanic and atmospheric variables from the NASA Global Modeling and Assimilation Office, we assess the skill of a chlorophyll concentrations forecast in the Equatorial Pacific for the period 2012-2015 with a focus on the forecast of the onset of the 2015 El Niño event. Using a series of retrospective 9-month hindcasts, we assess the uncertainties of the forecasted chlorophyll by comparing the monthly total chlorophyll concentration from the forecast with the corresponding monthly ocean chlorophyll data from the Suomi-National Polar-orbiting Partnership Visible Infrared Imaging Radiometer Suite (S-NPP VIIRS) satellite. The forecast was able to reproduce the phasing of the variability in chlorophyll concentration in the Equatorial Pacific, including the beginning of the 2015-2016 El Niño. The anomaly correlation coefficient (ACC) was significant (p < 0.05) for forecast at 1-month (R = 0.33), 8-month (R = 0.42) and 9-month (R = 0.41) lead times. The root mean square error (RMSE) increased from 0.0399 µg chl L-1 for the 1-month lead forecast to a maximum of 0.0472 µg chl L-1 for the 9-month lead forecast indicating that the forecast of the amplitude of chlorophyll concentration variability was getting worse. Forecasts with a 3-month lead time were on average the closest to the S-NPP VIIRS data (23% or 0.033 µg chl L-1) while the forecast with a 9-month lead time were the furthest (31% or 0.042 µg chl L-1). These results indicate the potential for forecasting chlorophyll concentration in this region but also highlights various deficiencies and suggestions for improvements to the current biogeochemical forecasting system. This system provides an initial basis for future applications including the effects of El Niño events on fisheries and other ocean resources given improvements identified in the analysis of these results.

14.
Front Mar Sci ; 4: 60, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29292403

RESUMO

The NASA PACE mission is a hyper-spectral radiometer planned for launch in the next decade. It is intended to provide new information on ocean biogeochemical constituents by parsing the details of high resolution spectral absorption and scattering. It is the first of its kind for global applications and as such, poses challenges for design and operation. To support pre-launch mission development and assess on-orbit capabilities, the NASA Global Modeling and Assimilation Office has developed a dynamic simulation of global water-leaving radiances, using an ocean model containing multiple ocean phytoplankton groups, particulate detritus, particulate inorganic carbon (PIC), and chromophoric dissolved organic carbon (CDOC) along with optical absorption and scattering processes at 1 nm spectral resolution. The purpose here is to assess the skill of the dynamic model and derived global radiances. Global bias, uncertainty, and correlation are derived using available modern satellite radiances at moderate spectral resolution. Total chlorophyll, PIC, and the absorption coefficient of CDOC (aCDOC), are simultaneously assimilated to improve the fidelity of the optical constituent fields. A 5-year simulation showed statistically significant (P <0.05) comparisons of chlorophyll (r = 0.869), PIC (r = 0.868), and aCDOC (r = 0.890) with satellite data. Additionally, diatoms (r = 0.890), cyanobacteria (r = 0.732), and coccolithophores (r = 0.716) were significantly correlated with in situ data. Global assimilated distributions of optical constituents were coupled with a radiative transfer model (Ocean-Atmosphere Spectral Irradiance Model, OASIM) to estimate normalized water-leaving radiances at 1 nm for the spectral range 250-800 nm. These unassimilated radiances were within -0.074 mW cm-2 µm1 sr-1 of MODIS-Aqua radiances at 412, 443, 488, 531, 547, and 667 nm. This difference represented a bias of -10.4% (model low). A mean correlation of 0.706 (P < 0.05) was found with global distributions of MODIS radiances. These results suggest skill in the global assimilated model and resulting radiances. The reported error characterization suggests that the global dynamical simulation can support some aspects of mission design and analysis. For example, the high spectral resolution of the simulation supports investigations of band selection. The global nature of the radiance representations supports investigations of satellite observing scenarios. Global radiances at bands not available in current and past missions support investigations of mission capability.

15.
Remote Sens Lett ; 8(12): 1102-1111, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29308292

RESUMO

A recent revision of the NASA global ocean colour record shows changes in global ocean chlorophyll trends. This new 18-year time series now includes three global satellite sensors, the Sea-viewing Wide Field of view Sensor (SeaWiFS), Moderate Resolution Imaging Spectroradiometer (MODIS-Aqua), and Visible Infrared Imaging Radiometer Suite (VIIRS). The major changes are radiometric drift correction, a new algorithm for chlorophyll, and a new sensor VIIRS. The new satellite data record shows no significant trend in global annual median chlorophyll from 1998 to 2015, in contrast to a statistically significant negative trend from 1998 to 2012 in the previous version. When revised satellite data are assimilated into a global ocean biogeochemical model, no trend is observed in global annual median chlorophyll. This is consistent with previous findings for the 1998-2012 time period using the previous processing version and only two sensors (SeaWiFS and MODIS). Detecting trends in ocean chlorophyll with satellites is sensitive to data processing options and radiometric drift correction. The assimilation of these data, however, reduces sensitivity to algorithms and radiometry, as well as the addition of a new sensor. This suggests the assimilation model has skill in detecting trends in global ocean colour. Using the assimilation model, spatial distributions of significant trends for the 18-year record (1998-2015) show recent decadal changes. Most notable are the North and Equatorial Indian Oceans basins, which exhibit a striking decline in chlorophyll. It is exemplified by declines in diatoms and chlorophytes, which in the model are large and intermediate size phytoplankton. This decline is partially compensated by significant increases in cyanobacteria, which represent very small phytoplankton. This suggests the beginning of a shift in phytoplankton composition in these tropical and subtropical Indian basins.

16.
J Bone Joint Surg Br ; 88(5): 606-13, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16645105

RESUMO

We compared peri-prosthetic bone mineral density between identical cemented and cementless LCS rotating platform total knee arthroplasties. Two matched cohorts had dual energy x-ray absorptiometry scans two years post-operatively using a modified validated densitometric analysis protocol, to assess peri-prosthetic bone mineral density. The knee that was not operated on was also scanned to enable the calculation of a relative bone mineral density difference. Oxford Knee and American Knee Society scores were comparable in the two cohorts. Statistical analysis revealed no significant difference in absolute, or relative peri-prosthetic bone mineral density with respect to the method of fixation. However, the femoral peri-prosthetic bone mineral density and relative bone mineral density difference were significantly decreased, irrespective of the method of fixation, particularly in the anterior distal portion of the femur, with a mean reduction in relative bone mineral density difference of 27%. There was no difference in clinical outcome between the cemented and cementless LCS total knee arthroplasty. However, both produce stress-shielding around the femoral implants. This leads us to question the use of more expensive cementless total knee components.


Assuntos
Artroplastia do Joelho , Densidade Óssea/fisiologia , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Cimentos Ósseos , Doenças Ósseas Metabólicas/fisiopatologia , Cimentação , Feminino , Fêmur/fisiopatologia , Colo do Fêmur/fisiopatologia , Humanos , Prótese do Joelho , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Osteoporose/fisiopatologia , Fatores Sexuais , Resultado do Tratamento
17.
Biochim Biophys Acta ; 1742(1-3): 151-60, 2004 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-15590065

RESUMO

Mobilization of intracellular calcium from inositol-1,4,5-triphosphate (IP3)-sensitive endoplasmic reticulum (ER) stores plays a prominent role in brain function. Mice heterozygous for the annexin A7 (Anx7) gene have a profound reduction in IP3 receptor function in pancreatic islets along with defective insulin secretion. We examined IP3-sensitive calcium pools in the brains of Anx7 (+/-) mice by utilizing ATP/Mg(2+)-dependent (45)Ca(2+) uptake into brain membrane preparations and tissue sections. Although the Anx7 (+/-) mouse brain displayed similar levels of IP3 binding sites and thapsigargin-sensitive (45)Ca(2+) uptake as that seen in wild-type mouse brain, the Anx7 (+/-) mouse brain Ca(2+) pools showed markedly reduced sensitivity to IP3. A potent and saturable Ca(2+)-releasing effect of recombinant ANX7 protein was demonstrated in mouse and rat brain membrane preparations, which was additive with that of IP3. We propose that ANX7 mobilizes Ca(2+) from an endoplasmic reticulum-like pool, which can be recruited to enhance IP3-mediated Ca(2+) release.


Assuntos
Anexina A7/fisiologia , Encéfalo/metabolismo , Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Animais , Anexina A7/genética , Anexina A7/metabolismo , Sequência de Bases , Primers do DNA , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley
18.
Cochrane Database Syst Rev ; (2): CD003420, 2005 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-15846664

RESUMO

BACKGROUND: Antithyroid drugs are widely used in the therapy of hyperthyroidism. There are wide variations in the dose, regimen or duration of treatment used by health professionals. OBJECTIVES: To assess the effects of dose, regimen and duration of antithyroid drug therapy for Graves' hyperthyroidism. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (Central), MEDLINE, EMBASE, BIOSIS, CINAHL, HEALTHSTAR, Current Controlled Trials and reference lists. We contacted investigators and hand searched conference abstracts. Most recent search: July 2004. SELECTION CRITERIA: Randomised and quasi-randomised trials of antithyroid medication for Graves' hyperthyroidism were used. DATA COLLECTION AND ANALYSIS: Trial allocation to included, excluded and awaiting assessment categories was made by consensus. Two reviewers independently extracted data and assessed trial quality. Pooling of data for primary outcomes, and select exploratory analyses were undertaken. MAIN RESULTS: Twenty-three randomised trials involving 3115 participants were included. Overall the quality of trials as reported was poor; specifically in terms of allocation concealment, assessor blinding and loss to follow-up. Four trials examined the effect of duration of therapy on relapse rates of Graves' hyperthyroidism. In one trial using the Titration regimen, longer duration therapy (18 months) had significantly fewer relapses (37% versus 58%) than six month therapy (Odds ratio (OR) 0.42, 95% confidence interval (CI) 0.18 to 0.96). In one quasi-randomised trial using the Block-Replace regimen, there was no significant difference between the six and 12 month (relapses rates 41% versus 35%) arms of the study. Extending the duration of therapy to over 18 months was not associated with improved relapse rates (Peto OR 0.75, 95% CI 0.39 to 1.43). Twelve trials examined the effect of Block-Replace versus Titration regimen. The relapse rates were similar in both groups at 51% in the Block-Replace group and 54% in the Titration group (Peto OR 0.86, 95% CI 0.68 to 1.08). Participants reporting rashes (10% versus 5%) and withdrawing due to side effects (16% versus 9%) were significantly higher in the Block-Replace group compared to the Titration group respectively. Three studies considered the addition of thyroxine with continued low dose antithyroid therapy after initial therapy with antithyroid drugs. There was significant heterogeneity between the studies and the difference between the two groups were not significant (Odds ratio 0.58, 95% CI 0.05 to 6.21). Four studies considered the addition of thyroxine alone after initial therapy with antithyroid drugs. There was no significant difference in the relapse rates between the groups after 12 months follow-up with relapse rates being 31% (88/282) with thyroxine and 29% (82/284) with placebo (Peto OR 1.15, 95% CI 0.79 to 1.67). AUTHORS' CONCLUSIONS: The evidence (based on four studies) suggests that the optimal duration of antithyroid drug therapy for the Titration regimen is 12 to 18 months. The six month Block-Replace regimen was found to be as effective as the 12 month treatment in one quasi-randomised study. The Titration (low dose) regimen had fewer adverse effects than the Block-Replace (high dose) regimen and was no less effective in trials (based on 12 trials) of equal duration. Continued thyroxine treatment following initial antithyroid therapy does not appear to provide any benefit in terms of recurrence of hyperthyroidism. The incidence of hypothyroidism was not reported and there were no deaths reported in the study populations.


Assuntos
Antitireóideos/administração & dosagem , Doença de Graves/tratamento farmacológico , Esquema de Medicação , Feminino , Humanos , Hipertireoidismo/tratamento farmacológico , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Tiroxina/administração & dosagem
20.
Stroke ; 32(4): 1012-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11283405

RESUMO

BACKGROUND AND PURPOSE: Grafts of MHP36 cells have previously been shown to reduce dysfunction after global ischemia in rats. To test their efficacy after focal ischemia, MHP36 cells were grafted 2 to 3 weeks after transient intraluminal middle cerebral artery occlusion (tMCAO) in rats. METHODS: MHP36 cells were implanted into the hemisphere contralateral to the lesion, with 8 deposits of 3 microL of cell suspension (25 000 cells per microliter). Sham grafted rats received equivalent volumes of vehicle. Three groups, sham-operated controls (n=11), MCAO+sham grafts (n=10), and MCAO+MHP36 grafts (n=11), were compared in 3 behavioral tests. RESULTS: In the bilateral asymmetry test, MCAO+MHP36 grafted rats exhibited neglect before grafting but subsequently showed no significant dysfunction, whereas MCAO+sham grafted rats showed stable sensorimotor deficits over 18 weeks relative to controls. MCAO+sham grafted rats demonstrated spontaneous motor asymmetry and increased rotational bias after injection of dopamine agonists. MCAO+MHP36 and control groups exhibited no bias in either spontaneous or drug-induced rotation. In contrast to motor recovery, MCAO+MHP36 grafted rats showed no improvement relative to MCAO+sham grafted rats in spatial learning and memory in the water maze. MCAO produced large striatal and cortical cavitations in both occluded groups. Lesion volume was significantly reduced (P<0.05) in the MCAO+MHP36 grafted group. The majority of MHP36 cells were identified within the intact grafted hemisphere. However, MHP36 cells were also seen in the cortex, striatum, and corpus callosum of the lesioned hemisphere. CONCLUSIONS: MHP36 cells may improve functional outcome after MCAO by assisting spontaneous reorganization in both the damaged and intact hemispheres.


Assuntos
Células Epiteliais/transplante , Neurônios/transplante , Transplante de Células-Tronco , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Anfetamina/farmacologia , Animais , Apomorfina/farmacologia , Comportamento Animal/efeitos dos fármacos , Diferenciação Celular , Linhagem Celular Transformada , Modelos Animais de Doenças , Dopaminérgicos/farmacologia , Células Epiteliais/citologia , Sobrevivência de Enxerto , Infarto da Artéria Cerebral Média/complicações , Masculino , Aprendizagem em Labirinto , Camundongos , Atividade Motora/efeitos dos fármacos , Neurônios/citologia , Ratos , Ratos Wistar , Tempo de Reação , Recuperação de Função Fisiológica , Células-Tronco/citologia , Acidente Vascular Cerebral/etiologia , Temperatura , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA