Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Int J Neurosci ; 133(2): 194-200, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33736564

RESUMO

Purpose:Tau hyperphosphorylation is a modification frequently observed after brain ischemia which has been related to the aggregation of this protein, with subsequent cytoskeletal damage, and cellular toxicity. The present study tests the hypothesis of using glucosamine, an agent that increases protein O-GlcNAcylation, to decrease the levels of phosphorylation in Tau during ischemia-reperfusion.Material and methods: Transient focal ischemia was artificially induced in male Wistar rats by occlusion of the middle cerebral artery (MCAO) with an intraluminal monofilament. A single dose of intraperitoneal glucosamine of 200 mg/kg diluted in normal saline (SSN) was administered 60 min before ischemia. Histological brain sections were processed using indirect immunofluorescence with primary antibodies (anti-O-GlcNAc and anti pTau-ser 396). The Image J software was used to calculate the immunofluorescence signal intensity.Results: The phosphorylation of Tau at the serine residue 396 had a significant decrease with the administration of glucosamine during ischemia-reperfusion compared with the administration of placebo.Conclusions: These results show that glucosamine can reduce the phosphorylation levels of Tau in rodents subjected to ischemia and cerebral reperfusion, which implies a neuroprotective role of glucosamine.


Assuntos
Isquemia Encefálica , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Ratos , Animais , Masculino , Glucosamina/farmacologia , Proteínas tau/metabolismo , Fosforilação , Ratos Wistar , Isquemia Encefálica/tratamento farmacológico , Isquemia , Reperfusão , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Fármacos Neuroprotetores/farmacologia
2.
Tree Physiol ; 42(7): 1364-1376, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35038335

RESUMO

Drought-related tree mortality is a global phenomenon that currently affects a wide range of forests. Key functional variables on plant hydraulics, carbon economy, growth and allocation have been identified and play a role in tree drought responses. However, tree mortality thresholds based on such variables are difficult to identify, especially under field conditions. We studied several Aleppo pine populations differently affected by an extreme drought event in 2014, with mortality rates ranging from no mortality to 90% in the most severely affected population. We hypothesized that mortality is linked with high levels of xylem embolism, i.e., hydraulic dysfunction, which would also lead to lower tree resistance to drought in subsequent years. Despite not finding any differences among populations in the vulnerability curves to xylem embolism, there were large differences in the hydraulic safety margin (HSM) and the hydraulic dysfunction level. High mortality rates were associated with a negative HSM when xylem embolism reached values over 60%. We also found forest weakening and post-drought mortality related to a low hydraulic water transport capacity, reduced plant growth, low carbohydrate contents and high pest infestation rates. Our results highlight the importance of drought severity and the hydraulic dysfunction level on pine mortality, as well as post-drought conditions during recovery processes.


Assuntos
Pinus , Árvores , Secas , Florestas , Pinus/fisiologia , Árvores/fisiologia , Água/fisiologia , Xilema/fisiologia
3.
Med. intensiva ; 34(6): [1-8], 2017. tab, fig
Artigo em Espanhol | LILACS | ID: biblio-883568

RESUMO

Introducción: El objetivo del estudio es describir y analizar la función tiroidea en el paciente crítico. Describir si algún patrón se asocia a una mayor tasa de mortalidad. Métodos: Se analizó a todos los pacientes ingresados en nuestra Unidad de Cuidados Intensivos, entre enero de 2015 y agosto de 2016, y que permanecieron allí, al menos, siete días. Resultados: Se incluyeron 242 pacientes. Se hallaron diferencias significativas en los valores medios de los índices de gravedad entre los no supervivientes y los supervivientes: SOFA (10,45 vs. 7,9); APACHE II (24,42 vs. 20,71); SAPS II (63,14 vs. 50,69). Se encontraron diferencias estadísticamente significativas en los valores medios de T3 en el grupo de supervivientes y no supervivientes: 1,5 pg/ml vs. 1,15 pg/ml (p <0,001; IC95% 0,224 ± 0,487). No hubo diferencias estadísticamente significativas en los valores medios de T4 y TSH. Al realizar el subanálisis según grupo de ingreso, no se hallaron diferencias estadísticamente significativas entre las cifras de TSH, T3 o T4. Sí hubo diferencias significativas en los valores medios de T3 en la mayor parte de los subgrupos. Conclusiones: Se hallaron diferencias estadísticamente significativas entre los valores medios de T3 en el grupo de supervivientes y no supervivientes. Los valores de T3 parecen asociarse a la mortalidad. Su descenso no parece asociarse a la enfermedad subyacente, sino a su gravedad.(AU)


Introduction: The aim of this study is to describe and analyse the thyroid function in the critically ill patient, and to describe if any pattern is associated with a higher mortality rate. Methods: Patients admitted to the Intensive Care Unit, between January 2015 and August 2016, with a stay of seven days or more, were enrolled. Results: Two hundred and forty-two patients were included. Significant differences were observed in the severity scores related to mortality during their stay in the Intensive Care Unit (no survivors vs. survivors): SOFA (10.45 vs. 7.9); APACHE II (24.42 vs. 20.71); SAPS II (63.14 vs. 50.69). Statistically significant differences were observed in the mean values of T3 between survivors and non-survivors: 1.5 pg/ml vs. 1.15 pg/ml (p <0.001; CI95% 0.224 ± 0.487). There were no statistically significant differences in the mean values of T4 and TSH. After subgroup analysis according to the admission group, no significant differences among the TSH, T3 and T4 values were detected. However a statistically difference in T3 average value was found in most subgroups. Conclusions: A statistically significant difference was found in mean T3 values in survivors and non-survivors. T3 concentration appears to be associated with mortality. Decrease of this thyroid hormone does not seem to associate with the underlying disease, but with its severity.(AU)


Assuntos
Humanos , Glândula Tireoide , Glândulas Endócrinas , Mortalidade
4.
Int J Neurosci ; 125(12): 936-40, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25350870

RESUMO

Tumor Necrosis Factor-alpha (TNF-α) is an immunomodulatory and proinflammatory cytokine implicated in neuro-inflammation and neuronal damage in response to cerebral ischemia. The present study tested the hypothesis that anti-TNF-α agents may be protective against cerebral infarction. Transient focal ischemia was artificially induced in anesthetized adult male Wistar rats (300-350 g) by middle cerebral artery occlusion (MCAO) with an intraluminal suture. TNF-α function was interfered with either a chimeric monoclonal antibody against TNF-α (infliximab-7 mg/kg) aiming to TNF-α soluble and membrane-attached form; or a chimeric fusion protein of TNF-α receptor-2 with a fragment crystallizable (Fc) region of IgG1 (etanercept-5 mg/kg) aiming for the TNF-α soluble form. Both agents were administered intraperitoneally 0 or 6 h after inducing ischemia. Infarct volume was measured by 2,3,5-triphenyltetrazolium chloride staining. Cerebral infarct volume was significantly reduced in either etanercept or infliximab-treated group compared with non-treated MCAO rats 24 h after reperfusion. These results suggest that anti-TNF-α agents may reduce focal ischemic injury in rats.


Assuntos
Lesões Encefálicas/prevenção & controle , Etanercepte/uso terapêutico , Infliximab/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo , Animais , Infarto Encefálico/etiologia , Infarto Encefálico/prevenção & controle , Lesões Encefálicas/etiologia , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , Masculino , Ratos , Ratos Wistar , Fatores de Tempo , Fator de Necrose Tumoral alfa/imunologia
5.
Enferm. glob ; 13(33): 318-327, ene. 2014.
Artigo em Espanhol | IBECS | ID: ibc-118498

RESUMO

Existen diversas organizaciones y movimientos humanitarios a nivel mundial que tratan de luchar contra las expresiones de deshumanización, sin embargo, continúa la presencia de situaciones que son causas de dolor en el mundo, por lo que debemos constituir una sociedad para que el mundo sea civilizado, vivir por la calidad de vida y no por acumular cifras estadísticas. El cuidado es una característica común de todos los seres vivos. Por consiguiente, el cuidado humano se reconoce como un concepto universal, inherente a la humanidad. Heidegger, el filósofo por excelencia del cuidado, reconoce que éste es "una constitución ontológica, siempre subyacente a todo lo que el ser humano emprende, proyecta y hace". Enfermería como profesión de naturaleza social intenta que su personal, bajo una óptica humanista, ayude a la persona solicitante del cuidado a reforzar potencialidades y/o minimizar desequilibrios en su estado de salud, por ello reconoce al ser humano como un ser complejo, misterioso, estructurado por diversas dimensiones que van de lo orgánico a lo espiritual, de lo tangible a lo intangible; con inclusión del aspecto social e histórico, que lo define como un ser de interrelaciones permanentes consigo mismo y el mundo. Bajo esta perspectiva, en enfermería, se procura reconocer que la persona cuidada es una entidad única, poseedora de atributos: conciencia, intelecto, dignidad, emociones, sentimientos y saberes, por lo tanto, el cuidado en enfermería asume una dimensión humanista y comprensiva del ser, cuya subjetividad está estructurada por sus vivencias y significados, sentimientos, emociones, intuiciones, razonamientos (AU)


Nowadays, there exist several organizations of humanitarian movements all over the world which try to fight against the dehumanization expressions; however there still exists the presence of situations which are the reasons of pain in the world. That is why we must construct a better and civilized world in which people worries about the quality of life instead of accumulating statistical numbers .Care is a common feature of all human beings. Therefore, human care is recognized as a universal concept, inherent in humanity. Heidegger, the philosopher for excellence of care, recognizes that this is "an ontological constitution that is always underlying to all what the human beings begin, project and make." Nursing as a profession of social nature tries that its staff , under an humanistic perspective , helps the person interested in care to reinforce his /her abilities and /or to minimize imbalances in her /his state of health .That is why it recognizes the human beings as a complex , mysterious and structured in several dimensions being that range from the organic to the spiritual, from the tangible to the intangible , including the social and historical aspect , which defines it as a being of permanent relationships with himself and the world. Under this point of view, nursing tries to recognize that the cared person is a unique entity which has attributes such as: awareness, intellect, dignity, emotions, feelings and knowledge. Therefore, the nursing care assumes a comprehensive and humanistic dimension of the human being whose subjectivity is structured by his experiences ,meanings , feelings , emotions , intuitions ,and reasoning (AU)


Assuntos
Humanos , Masculino , Feminino , Cuidados de Enfermagem/organização & administração , Cuidados de Enfermagem/normas , Cuidados de Enfermagem/tendências , Relações Interpessoais , Prática Profissional/ética , Prática Profissional/legislação & jurisprudência , Prática Profissional/normas , Cuidados de Enfermagem/ética , Cuidados de Enfermagem/métodos , Cuidados de Enfermagem , Apoio Social , Impacto Psicossocial , Prática Profissional/organização & administração , Prática Profissional
6.
Appl Radiat Isot ; 71 Suppl: 75-80, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22494894

RESUMO

A Monte Carlo calculation, using the MCNPX code, was carried out in order to estimate the photon and neutron spectra in two locations of two linacs operating at 15 and 18 MV. Detailed models of both linac heads were used in the calculations. Spectra were estimated below the flattening filter and at the isocenter. Neutron spectra show two components due to evaporation and knock-on neutrons. Lethargy spectra under the filter were compared to the spectra calculated from the function quoted by Tosi et al. that describes reasonably well neutron spectra beyond 1 MeV, though tends to underestimate the energy region between 10(-6) and 1 MeV. Neutron and the Bremsstrahlung spectra show the same features regardless of the linac voltage.


Assuntos
Nêutrons , Aceleradores de Partículas , Fótons , Método de Monte Carlo
7.
Plant Dis ; 92(11): 1589, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30764454

RESUMO

In the United States, yellows disease of sugar beet (Beta vulgaris), which causes wilt, early death, and yield reduction, is caused primarily by Fusarium oxysporum f. sp. betae (3,4), but F. graminearum (2) has also been implicated. During the past 3 years, a similar disease causing yellowing and severe decline appeared in some sugar beet fields of central and southwest Minnesota planted with cultivars resistant to yellows. The disease has become a concern to the local sugar beet industry, which produces 56% of sugar beets in the United States. From 2005 to 2007, isolations were made from sugar beets collected in commercial fields and from a Fusarium screening nursery showing symptoms of yellowing, interveinal chlorosis, scorching, stunting, vascular discoloration of the taproot, and early death of plants. Of 96 Fusarium isolates recovered and used in root-dip inoculation trials in the greenhouse, 58 were pathogenic to sugar beets. On the basis of morphology, 12 were identified as F. oxysporum, 6 as F. graminearum, and 40 as a novel Fusarium species. The remaining 38 isolates were nonpathogenic. All three pathogenic Fusarium species were isolated from taproots, but only the novel Fusarium was isolated from petioles. In culture, the novel Fusarium exhibited a bright orange color on the underside of potato dextrose agar medium and produced micro- and macroconidia sparsely. Hyphal tip isolates of all novel Fusarium isolates were pathogenic, causing typical yellowing symptoms and plant death to the Fusarium yellows susceptible sugar beet cv. VDH46177 in replicated greenhouse trials. Isolates were successfully reisolated from the symptomatic plants, fulfilling Koch's postulates. Restriction fragment length polymorphism (RFLP) endonuclease digestion patterns (Alu1, Fnu4HI, HaeIII, and HhaI) of the internal transcribed spacer (ITS) region of 40 pathogenic novel isolates showed a distinct pattern compared with known Fusarium species. Thin layer chromatography analysis of 13 novel isolates detected the type A trichothecenes neosolaniol and 4,15-diacetoxyscirpenol. Partial sequences of the translation elongation factor 1-α (TEF) from 12 single-spored novel Fusarium isolates were generated. BLAST analysis of the TEF sequence against the FUSARIUM-ID (1) and GenBank databases did not match any known Fusarium species. On the basis of pathogenicity, morphology, RFLP patterns, mycotoxin production, and TEF sequence analysis it appears that this is a new species of Fusarium, but additional multilocus phylogenetic analyses are warranted. The natural occurrence of this novel Fusarium pathogen in sugar beet may have implications in breeding for resistance to Fusarium yellows, since yellow decline has been observed in purportedly Fusarium-tolerant cultivars in the Minnesota and North Dakota production regions. References: (1) D. M. Geiser et al. Eur. J. Plant Pathol. 110:473, 2004. (2) L. E. Hanson. Plant Dis. 90:686, 2006. (3). L. E. Hanson. Plant Dis. 90:1554, 2006. (4) C. E. Windels et al. Plant Dis. 89:341, 2005.

8.
Plant Foods Hum Nutr ; 58(4): 285-97, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15354788

RESUMO

Common beans (Phaseolus vulgaris L) contain a number of antinutritional factors such as condensed tannins. Reducing tannin concentration might contribute to improving the nutritional quality of common bean. But polyphenolics are involved in resistance to diseases and pests, and reducing tannin concentration may have a negative effect on plant resistance. Furthermore, the effects of tannin on disease resistance in different gene pools or in different seed colors are not defined. To investigate these effects, 790 accessions from a common bean core collection were investigated. Data were subjected to independent sample t-tests, and the calculation of correlation coefficients. The mean coat extracts of black and red bean classes were highest (with 0.129 g/g and 0.124 g/g of seed coat, respectively). Among the gene pools, the coat extract was greater in the Middle American gene pool (0.129 g/g) than in the Andean gene pool (0.108 g/g). Coat extract in the Andean gene pool was positively correlated with susceptibility to Middle American isolates of anthracnose and to common bacterial blight, but negatively correlated with susceptibility to Andean isolates of angular leaf spot and to empoasca. Only empoasca damage showed negative correlation with coat extract in the Middle American gene pool. However within gene pools, the coat extracts of different seed classes varied in correlations with reactions to disease and pest infestations. Significant correlations were particularly associated with the black seed class in both gene pools. The relationships between coat extract and disease reactions are complex. A better understanding will help breeders to select germplasm with improved nutritional quality without adversely affecting disease resistance.


Assuntos
Controle Biológico de Vetores , Phaseolus/fisiologia , Doenças das Plantas/genética , Sementes/fisiologia , Taninos/imunologia , Cruzamento , Cor , Pool Gênico , Genótipo , Imunidade Inata/fisiologia , Phaseolus/genética , Doenças das Plantas/microbiologia , Sementes/genética
9.
J Physiol ; 528(Pt 3): 419-33, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11060121

RESUMO

Ca2+ sparks were monitored by confocal laser-scanning microscopy of fluo-3 at video rates, in fast twitch muscle fibres, stimulated by exposure to caffeine and/or low [Mg2+]. Scanning was in two spatial dimensions ('2D') or 2D plus time, at 4 ms per image frame. Sparks were identified in 2D images of normalized fluorescence by an automatic procedure, which also evaluated the event's location and morphometric parameters. Most sparks were circular, but some were elongated, especially in caffeine. Separation of the spark from circular symmetry was quantified by its eccentricity (length/width - 1). In an internal solution with 0.4 mM [Mg2+], sparks (989 events in 4 cells) had amplitude 0.73, width 1.94 microm, length 2.12 microm and eccentricity not significantly different from 0. Upon application of 1 mM caffeine, length (of 2578 events in the same cells) increased significantly (by 0.41 microm, or 19 %), width increased by 0.18 microm (9 %) and amplitude decreased slightly. The eccentricity became significantly different from 0, and the sparks' long axis predominantly oriented parallel to the plane of the Z disks. More than 10 % of the events in caffeine had length greater than 4 microm, a relatively flat top, and a sharp termination at both ends of the major axis. Additionally, there was only a weak correlation between eccentricity and amplitude. These properties suggest that the elongated events are produced by simultaneous opening of multiple channels within a junction, rather than anisotropic diffusion of Ca2+ or random overlap of round sparks. Elongated events often increased in eccentricity early in their evolution. Then, most remained elongated during their rise and decay, while others spread spatially in the plane of the Z disks. In 1-2 % of the events, the centre of mass migrated in space, over time, at approximately 0.1 microm x ms(-1). These spatio-temporal features require the involvement of multiple release channels, at spatially resolvable locations. Because sources often spread over distances greater than 1 or 2 microm, and arrays of junctional elements (couplons) are at most 1.2 microm long, it must be possible for activation of release to propagate between neighbouring couplons, especially under the influence of caffeine and/or low [Mg2+].


Assuntos
Cálcio/metabolismo , Microscopia Confocal , Músculo Esquelético/metabolismo , Compostos de Anilina , Animais , Cafeína/farmacologia , Corantes Fluorescentes , Técnicas In Vitro , Magnésio/farmacologia , Músculo Esquelético/efeitos dos fármacos , Concentração Osmolar , Rana pipiens , Fatores de Tempo , Xantenos
10.
J Dermatol ; 26(12): 808-12, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10659502

RESUMO

Encephalocraniocutaneous lipomatosis is a rare neurocutaneous syndrome characterized by lipomatous hamartomas ranging in size from a few millimeters to several centimeters and affecting the head. Ocular anomalies and a variable degree of mental retardation with or without convulsions are usually observed. This disorder should be distinguished from other mosaic neurocutaneous phenotypes such as Proteus syndrome, oculocerebrocutaneous syndrome, and nevus sebaceous syndrome. We report the clinicopathologic findings of a 4-year-old Brazilian girl affected by this syndrome and review the literature. To our best knowledge, this is the first documented case of encephalocraniocutaneous lipomatosis occurring sporadically in South America.


Assuntos
Síndromes Neurocutâneas , Pré-Escolar , Diagnóstico Diferencial , Feminino , Hamartoma/patologia , Humanos , Deficiência Intelectual , Lipoma/patologia , Síndromes Neurocutâneas/patologia
11.
Obstet Gynecol ; 68(2): 204-8, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3090492

RESUMO

A clinical trial of levonorgestrel-releasing Norplant implants used for contraception was undertaken in two cities in Colombia. Through two years in which 389 women had accumulated 594 years of use, there were no pregnancies. In a comparison group of copper intrauterine device acceptors, the one-year pregnancy rate was 1.1 per 100. Menstrual disturbances associated with progestin-only administration were the principal side-effects, and the major reason for cessation of use. Continuation among users of the implants was at the same or at a higher rate than observed among users of the intrauterine device. Advantages and disadvantages of alternate sites for implant placement are discussed.


Assuntos
Norgestrel/administração & dosagem , Adolescente , Adulto , Ensaios Clínicos como Assunto , Colômbia , Implantes de Medicamento , Feminino , Humanos , Dispositivos Intrauterinos de Cobre , Levanogestrel , Ciclo Menstrual/efeitos dos fármacos , Distúrbios Menstruais/induzido quimicamente , Norgestrel/efeitos adversos , Gravidez , Estudos Prospectivos , Estereoisomerismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...