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1.
Exp Gerontol ; 156: 111607, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34715304

RESUMEN

The effects of aging on ROS production and DNA damage were assessed in hematopoietic stem cells (HSCs) from apolipoprotein E-deficient (ApoE-/-) mice (2-, 12- and 24-month-old), a traditional experimental model of atherogenic dyslipidemia. HSCs from aged ApoE-/- mice were associated with increased ROS levels, leading to loss quiescence, DNA damage, apoptosis and telomere shortening. The concurrence of lack of ApoE and aging result in exhaustion and senescence of HSCs accompanied by increased oxidative stress and inflammation. Therefore, our data open avenues to a better understanding of age-related changes and genetic factors, which may synergistically compromise the efficacy of aged HSC recovery and/or transplantation.


Asunto(s)
Células Madre Hematopoyéticas , Estrés Oxidativo , Envejecimiento , Animales , Apolipoproteínas E/genética , Senescencia Celular , Daño del ADN , Ratones , Ratones Endogámicos C57BL , Especies Reactivas de Oxígeno
2.
Photodiagnosis Photodyn Ther ; 34: 102312, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33930577

RESUMEN

Fourier Transform-Infrared (FT-IR) absorption spectroscopy has been used to investigate pathophysiological changes caused by sepsis. Sepsis has been defined as a potentially fatal organic dysfunction caused by a dysregulated host response to infection and can lead a patient to risk of death. This study used samples consisting of the blood plasma of mice which were induced to sepsis state, compared to a healthy group using FT-IR associated with attenuated total reflectance (ATR) spectroscopy. For statistical analysis, principal components analysis (PCA) and linear discriminant analysis (LDA) were applied, independently, to the second derivative spectra of both the fingerprint (900-1800 cm-1) and the high wavenumber (2800-3100 cm-1) regions. The technique efficiently differentiated the blood plasma of the two groups, sepsis and healthy mice, the analysis indicating that fatty acids and lipids in the blood samples could be an important biomarker of sepsis.


Asunto(s)
Fotoquimioterapia , Sepsis , Animales , Atención a la Salud , Humanos , Ratones , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes , Espectroscopía Infrarroja por Transformada de Fourier
3.
Arq. bras. med. vet. zootec. (Online) ; 72(3): 895-900, May-June, 2020. ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1129565

RESUMEN

An adult, female, 31kg body weight, free range Myrmecophaga tridactyla was referred for medical consultation due to apathy, dehydration, intense flatulence and fetid stools. The animal was submitted to chemical restraint and physical examination, blood count, fecal analysis, and vaginal cytology and abdominal ultrasonography were performed. Good nutritional status and clinical variables within the normal range were observed at physical examination. At vaginal cytology leukocytes, spermatozoa and a large proportion of cornified cells (superficial) were observed, indicating estrus and recent copula. At ultrasound examination it was possible to locate, identify, evaluate and measure the ovaries and the uterine structures, cervix, body, lumen, myometrium and endometrium, a fact never reported in the literature for this species. These data can be used as reference for clinical evaluation of the reproductive tract in Myrmecophaga tridactyla females considered vulnerable species, for the diagnosis of reproductive pathologies, biotechnologies application or estrous cycle evaluation.(AU)


Uma fêmea, com 31kg de peso corporal, de Myrmecophaga tridactyla, de vida livre, foi apresentada para consulta médica em razão de apatia, desidratação, flatulência intensa e fezes fétidas. O animal foi submetido à contenção química e foram realizados exame físico, hemograma, análise fecal, citologia vaginal e ultrassonografia abdominal. Ao exame físico, foi determinado bom estado nutricional e variáveis clínicas dentro da faixa de normalidade. Na citologia vaginal, foram observados leucócitos, espermatozoides e uma grande proporção de células cornificadas (superficiais), indicando estro e cópula recente. No exame ultrassonográfico, foi possível localizar, identificar, avaliar e mensurar os ovários e as estruturas uterinas, o colo do útero, o corpo do útero, o lúmen, o miométrio e o endométrio, fato nunca relatado na literatura para essa espécie. Esses dados podem ser utilizados como referência para avaliação clínica do trato reprodutivo de fêmeas de Myrmecophaga tridactyla considerada espécie vulnerável, para o diagnóstico de patologias reprodutivas, aplicação de biotecnologias ou avaliação do ciclo estral.(AU)


Asunto(s)
Animales , Femenino , Ovario/diagnóstico por imagen , Útero/diagnóstico por imagen , Xenarthra/anatomía & histología , Genitales/diagnóstico por imagen , Ultrasonografía/veterinaria , Ciclo Estral
4.
Braz. j. biol ; 79(4): 659-664, Nov. 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1001473

RESUMEN

Abstract The Doce River basin has suffered the largest environmental accident ever occurred in Brazil with the influx of tailings from Fundão and Santarém, belonging to Samarco mining company, due to the disaster in Mariana. A spill between 50 and 60 million m3 of tailings was estimated by the company. According to Samarco, the wastewater was composed mainly of clay, silt and heavy metals like iron, copper and manganese. Thereby, the objective of the present study was evaluated the genotoxic damage in juvenile of Geophagus brasiliensis (Quoy e Gaimard, 1824) exposed to Doce river water before (DRWBA - Doce River water before acident) and after (DRWAA - Doce River water after acident) the influx of tailings from the Germano and Santarém Dam disasters in Mariana, MG, Brazil. For this, 24 individuals of the species G. brasiliensis (obtained on IFES/ALEGRE fish culture) were submitted to a bioassay with three treatments and eight replicates. The treatments were: 1) Control water (water from the urban water supply system, filtered with a 0.45 µm membrane), 2) DRBA and 3) DRAA. After 96 h, these fishes were anesthetized to remove blood for evaluation of genotoxic damage (micronucleus and comet). For the bioassay, a total of 80 L of The Doce River water were collected before the influx of tailings and after the influx and then submitted to metal quantification analysis. Fish exposed to DRWBA and DRWAA treatments showed a significant increase in both the number of erythrocyte micronuclei and the DNA damage index in relation to the control fish; however, they did not present any differences between the two treatments. The results demonstrate that the DRWBA treatment was already genotoxic for the fish, mainly due to dissolved Cu concentrations in the water. The DRWAA treatment probably presented genotoxicity due to the increase in the dissolved fraction and synergistic effects of several metals found in the tailings of the Mariana accident.


Resumo A bacia do Rio Doce sofreu o maior acidente ambiental com o influxo de rejeitos de Fundão e Santarém, pertencentes à empresa de mineração Samarco, devido ao desastre em Mariana. Um derramamento entre 50 e 60 milhões de m3 de rejeitos foi estimado pela empresa. De acordo com a Samarco, o rejeito despejado era composto principalmente de argila, silte e alguns metais pesados como ferro, cobre e manganês. Com isso, o presente estudo teve como objetivo avaliar os danos genotóxicos em juvenis de Geophagus brasilienses expostos a água do rio Doce antes (DRWAA - água do Rio Doce antes do acidente) e depois (DRWBA- água do Rio Doce depois do acidente) da chegada dos rejeitos do rompimento das barragens de Germano e Santarém em Mariana, MG, Brasil. Para isso, 24 indivíduos da espécie G. brasilienses (obtidos na piscicultura do IFES/ALEGRE) foram submetidos a um bioensaio com três tratamentos e oito réplicas. Os tratamentos eram: 1) Controle (com água do abastecimento urbano, filtrada com filtro analítico de 0,45 µm); 2) DRWBA e 3) DRWAA. Após um período de 96 h, esses peixes foram anestesiados para retirada de sangue para avaliação dos danos genotóxicos (micronúcleo e cometa). Para a realização do bioensaio, um total de 80 L de água do Rio Doce foram coletados antes da chegada dos rejeitos e outros 80 L foram coletados depois da chegada dos rejeitos e ambas foram submetidas a análises de quantificação de metal. Os peixes expostos ao DRWBA e ao DRWAA apresentaram um aumento significativo na quantidade de micronúcleos eritrocitários e no índice de danos do DNA em relação aos peixes controle, no entanto não apresentaram diferenças entre si. Os resultados obtidos demonstram que a DRWBA já era genotóxica para os peixes, principalmente, em função das concentrações de Cu dissolvido na água. A DRWAA apresentou genotixicidade, provavelmente, em função do aumento da fração dissolvida e do efeito sinérgico de diversos metais presentes nos rejeitos do acidente de Mariana.


Asunto(s)
Animales , Daño del ADN/efectos de los fármacos , Metales Pesados/análisis , Metales Pesados/clasificación , Cíclidos/fisiología , Cíclidos/genética , Desastres , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/clasificación , Contaminantes Químicos del Agua/toxicidad , Brasil , Monitoreo del Ambiente/métodos , Metales Pesados/toxicidad , Ríos/química , Agua Dulce/química , Minería
5.
Sci Rep ; 9(1): 14620, 2019 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-31601823

RESUMEN

Galectin-3 (Gal-3) controls intercellular and cell-extracellular matrix interactions during immunological responses. In chronic inflammation, Gal-3 is associated with fibrotic events, regulates B cell differentiation and delays lupus progression. Gal-3 deficient mice (Lgals3-/-) have intense germinal center formation and atypical plasma cell generation correlated to high levels IgG, IgE, and IgA. Here, we used pristane (2,6,10,14-tetramethylpentadecane) to induce lupus-like syndrome in Lgals3-/- and Lgals3+/+ BALB/c mice. Mesentery and peritoneal cells were monitored because promptly react to pristane injected in the peritoneal cavity. For the first time, mesenteric tissues have been associated to the pathogenesis of experimental lupus-like syndrome. In Lgals3+/+ pristane-induced mice, mesentery was hallmarked by intense fibrogranulomatous reaction restricted to submesothelial regions and organized niches containing macrophages and B lymphocytes and plasma cells. In contrast, Lgals3-/- pristane-treated mice had diffuse mesenteric fibrosis affecting submesothelium and peripheral tissues, atypical M1/M2 macrophage polarization and significant DLL1+ cells expansion, suggesting possible involvement of Notch/Delta pathways in the disease. Early inflammatory reaction to pristane was characterized by significant disturbances on monocyte recruitment, macrophage differentiation and dendritic cell (DC) responses in the peritoneal cavity of pristane-induced Lgals3-/- mice. A correlative analysis showed that mesenteric damages in the absence of Gal-3 were directly associated with severe portal inflammation and hepatitis. In conclusion, it has suggested that Gal-3 orchestrates histological organization in the mesentery and prevents lupoid hepatitis in experimental lupus-like syndrome by controlling macrophage polarization, Notch signaling pathways and DC differentiation in mesenteric structures.


Asunto(s)
Galectina 3/metabolismo , Hepatitis/inmunología , Lupus Eritematoso Sistémico/inmunología , Macrófagos Peritoneales/inmunología , Mesenterio/patología , Animales , Modelos Animales de Enfermedad , Femenino , Fibrosis , Galectina 3/genética , Hepatitis/patología , Humanos , Inyecciones Intraperitoneales , Hígado/inmunología , Hígado/patología , Lupus Eritematoso Sistémico/inducido químicamente , Lupus Eritematoso Sistémico/complicaciones , Mesenterio/citología , Mesenterio/inmunología , Ratones , Ratones Noqueados , Terpenos/administración & dosificación , Terpenos/inmunología
6.
Braz J Biol ; 79(4): 659-664, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30462813

RESUMEN

The Doce River basin has suffered the largest environmental accident ever occurred in Brazil with the influx of tailings from Fundão and Santarém, belonging to Samarco mining company, due to the disaster in Mariana. A spill between 50 and 60 million m3 of tailings was estimated by the company. According to Samarco, the wastewater was composed mainly of clay, silt and heavy metals like iron, copper and manganese. Thereby, the objective of the present study was evaluated the genotoxic damage in juvenile of Geophagus brasiliensis (Quoy e Gaimard, 1824) exposed to Doce river water before (DRWBA - Doce River water before acident) and after (DRWAA - Doce River water after acident) the influx of tailings from the Germano and Santarém Dam disasters in Mariana, MG, Brazil. For this, 24 individuals of the species G. brasiliensis (obtained on IFES/ALEGRE fish culture) were submitted to a bioassay with three treatments and eight replicates. The treatments were: 1) Control water (water from the urban water supply system, filtered with a 0.45 µm membrane), 2) DRBA and 3) DRAA. After 96 h, these fishes were anesthetized to remove blood for evaluation of genotoxic damage (micronucleus and comet). For the bioassay, a total of 80 L of The Doce River water were collected before the influx of tailings and after the influx and then submitted to metal quantification analysis. Fish exposed to DRWBA and DRWAA treatments showed a significant increase in both the number of erythrocyte micronuclei and the DNA damage index in relation to the control fish; however, they did not present any differences between the two treatments. The results demonstrate that the DRWBA treatment was already genotoxic for the fish, mainly due to dissolved Cu concentrations in the water. The DRWAA treatment probably presented genotoxicity due to the increase in the dissolved fraction and synergistic effects of several metals found in the tailings of the Mariana accident.


Asunto(s)
Cíclidos , Daño del ADN/efectos de los fármacos , Desastres , Metales Pesados , Animales , Brasil , Cíclidos/genética , Cíclidos/fisiología , Monitoreo del Ambiente/métodos , Agua Dulce/química , Metales Pesados/análisis , Metales Pesados/clasificación , Metales Pesados/toxicidad , Minería , Ríos/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/clasificación , Contaminantes Químicos del Agua/toxicidad
7.
Science ; 356(6344): 1269-1272, 2017 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-28642434

RESUMEN

In the lower solar atmosphere, the chromosphere is permeated by jets known as spicules, in which plasma is propelled at speeds of 50 to 150 kilometers per second into the corona. The origin of the spicules is poorly understood, although they are expected to play a role in heating the million-degree corona and are associated with Alfvénic waves that help drive the solar wind. We compare magnetohydrodynamic simulations of spicules with observations from the Interface Region Imaging Spectrograph and the Swedish 1-m Solar Telescope. Spicules are shown to occur when magnetic tension is amplified and transported upward through interactions between ions and neutrals or ambipolar diffusion. The tension is impulsively released to drive flows, heat plasma (through ambipolar diffusion), and generate Alfvénic waves.

8.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467242

RESUMEN

Abstract The Doce River basin has suffered the largest environmental accident ever occurred in Brazil with the influx of tailings from Fundão and Santarém, belonging to Samarco mining company, due to the disaster in Mariana. A spill between 50 and 60 million m3 of tailings was estimated by the company. According to Samarco, the wastewater was composed mainly of clay, silt and heavy metals like iron, copper and manganese. Thereby, the objective of the present study was evaluated the genotoxic damage in juvenile of Geophagus brasiliensis (Quoy e Gaimard, 1824) exposed to Doce river water before (DRWBA Doce River water before acident) and after (DRWAA Doce River water after acident) the influx of tailings from the Germano and Santarém Dam disasters in Mariana, MG, Brazil. For this, 24 individuals of the species G. brasiliensis (obtained on IFES/ALEGRE fish culture) were submitted to a bioassay with three treatments and eight replicates. The treatments were: 1) Control water (water from the urban water supply system, filtered with a 0.45 µm membrane), 2) DRBA and 3) DRAA. After 96 h, these fishes were anesthetized to remove blood for evaluation of genotoxic damage (micronucleus and comet). For the bioassay, a total of 80 L of The Doce River water were collected before the influx of tailings and after the influx and then submitted to metal quantification analysis. Fish exposed to DRWBA and DRWAA treatments showed a significant increase in both the number of erythrocyte micronuclei and the DNA damage index in relation to the control fish; however, they did not present any differences between the two treatments. The results demonstrate that the DRWBA treatment was already genotoxic for the fish, mainly due to dissolved Cu concentrations in the water. The DRWAA treatment probably presented genotoxicity due to the increase in the dissolved fraction and synergistic effects of several metals found in the tailings of the Mariana accident.


Resumo A bacia do Rio Doce sofreu o maior acidente ambiental com o influxo de rejeitos de Fundão e Santarém, pertencentes à empresa de mineração Samarco, devido ao desastre em Mariana. Um derramamento entre 50 e 60 milhões de m3 de rejeitos foi estimado pela empresa. De acordo com a Samarco, o rejeito despejado era composto principalmente de argila, silte e alguns metais pesados como ferro, cobre e manganês. Com isso, o presente estudo teve como objetivo avaliar os danos genotóxicos em juvenis de Geophagus brasilienses expostos a água do rio Doce antes (DRWAA água do Rio Doce antes do acidente) e depois (DRWBA- água do Rio Doce depois do acidente) da chegada dos rejeitos do rompimento das barragens de Germano e Santarém em Mariana, MG, Brasil. Para isso, 24 indivíduos da espécie G. brasilienses (obtidos na piscicultura do IFES/ALEGRE) foram submetidos a um bioensaio com três tratamentos e oito réplicas. Os tratamentos eram: 1) Controle (com água do abastecimento urbano, filtrada com filtro analítico de 0,45 µm); 2) DRWBA e 3) DRWAA. Após um período de 96 h, esses peixes foram anestesiados para retirada de sangue para avaliação dos danos genotóxicos (micronúcleo e cometa). Para a realização do bioensaio, um total de 80 L de água do Rio Doce foram coletados antes da chegada dos rejeitos e outros 80 L foram coletados depois da chegada dos rejeitos e ambas foram submetidas a análises de quantificação de metal. Os peixes expostos ao DRWBA e ao DRWAA apresentaram um aumento significativo na quantidade de micronúcleos eritrocitários e no índice de danos do DNA em relação aos peixes controle, no entanto não apresentaram diferenças entre si. Os resultados obtidos demonstram que a DRWBA já era genotóxica para os peixes, principalmente, em função das concentrações de Cu dissolvido na água. A DRWAA apresentou genotixicidade, provavelmente, em função do aumento da fração dissolvida e do efeito sinérgico de diversos metais presentes nos rejeitos do acidente de Mariana.

9.
Ecohealth ; 13(4): 743-760, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27638472

RESUMEN

This study analyzed the evolution of socioeconomic, sanitary, and personal factors as well as spatiotemporal changes in the prevalence of helminthiasis and giardiasis in urban Amazonian children between 2003 and 2011. Child age, lack of sanitation, and lack of access to bottled water were identified as significant associated factors for helminthiasis and giardiasis. There was an overall improvement in socioeconomic and sanitary conditions in the city resulting in decreased helminth prevalences from 12.42 to 9.63% between 2003 and 2010, but the prevalence increased to 15.03% in 2011 due to migratory movement and unstable sanitary conditions. As for Giardiasis, socioeconomic and environmental changes were not enough to reduce prevalence (16% in 2003 and 23% in 2011). Spatial analysis identified a significant cluster for helminthiasis in an area of poor housing conditions. Control programs in the Amazon need to target high-risk areas focusing changes in sanitation, water usage, and health education.


Asunto(s)
Giardiasis/epidemiología , Helmintiasis/epidemiología , Factores Socioeconómicos , Niño , Preescolar , Ciudades , Femenino , Giardiasis/economía , Helmintiasis/economía , Humanos , Masculino , Prevalencia , Factores de Riesgo , Saneamiento
10.
Braz J Biol ; 76(1): 233-44, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26871748

RESUMEN

The morphology and anatomy of the flower of Dalechampia alata, as well as the chemical nature of the exudates secreted in the inflorescence were studied using light microscope. This is the first report showing the presence of colleters in the genus Dalechampia. In the staminate flower occur a group of small secretory glands. The histochemical results indicate that the substance secreted from the glands is lipidic and resinuous in nature, while in the colleters it consists of polysaccharides and lipid-rich substances. The ovule of D. alata are anatropous, subglobose and bitegmic. It presents obturator, micropyle occluded by nucellar beak and meristematic activity in the ovary wall. The secretion produced in the stigmatic and transmitting tissue consists of polysaccharides.


Asunto(s)
Euphorbiaceae/anatomía & histología , Euphorbiaceae/química , Animales , Inflorescencia/anatomía & histología , Inflorescencia/química
11.
Braz. j. biol ; 76(1): 233-244, Feb. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-774511

RESUMEN

Abstract The morphology and anatomy of the flower of Dalechampia alata, as well as the chemical nature of the exudates secreted in the inflorescence were studied using light microscope. This is the first report showing the presence of colleters in the genus Dalechampia. In the staminate flower occur a group of small secretory glands. The histochemical results indicate that the substance secreted from the glands is lipidic and resinuous in nature, while in the colleters it consists of polysaccharides and lipid-rich substances. The ovule of D. alata are anatropous, subglobose and bitegmic. It presents obturator, micropyle occluded by nucellar beak and meristematic activity in the ovary wall. The secretion produced in the stigmatic and transmitting tissue consists of polysaccharides.


Resumo A morfologia e anatomia das flores de Dalechampia alata, bem como a natureza química dos exsudatos secretados na inflorescência foram analisadas utilizando microscopia de luz. Este é o primeiro relato de coléteres para o gênero Dalechampia. Um grupo de pequenas glândulas secretoras ocorre nas flores estaminadas. Os resultados dos testes histoquímicos indicam que a substância secretada pelas glândulas apresenta natureza lipídica e resinosa, enquanto nos coléteres a secreção é constituída de polissacarídeos e lipídeos. O ovulo de D. alata é anátropo, subgloboso e bitegumentado. A presença de obturador, projeção do tecido nucelar pela micrópila e atividade meristemática na parede do ovário foram relatadas. A secreção do estigma e do tecido transmissor é constituída de polissacarídeos.


Asunto(s)
Animales , Euphorbiaceae/anatomía & histología , Euphorbiaceae/química , Inflorescencia/anatomía & histología , Inflorescencia/química
12.
Rev. bras. plantas med ; 17(3): 392-397, Jul-Sep/2015. tab, graf
Artículo en Portugués | LILACS | ID: lil-752554

RESUMEN

RESUMO No Brasil, a família Malvaceae está representada por aproximadamente 200 espécies e algumas foram descritas como gastroproteroras. Pavonia alnifolia A.St.-Hil. (Malvaceae) foi selecionada após uma abordagem quimiossistemática, considerando-se sua potencial capacidade em prevenir lesões gástricas. Assim, a atividade gastroprotetora do extrato etanólico de caules de P. alnifolia foi avaliada utilizando o modelo de indução aguda da lesão gástrica por etanol acidificado em camundongos. Além disso, foram quantificados o teor de flavonóides, pelo método de cloreto de alumínio, e de polifenóis, pelo método Folin-Ciocalteu, uma vez que a relação desses componentes com a proteção gástrica foi evidenciada. Os ensaios apontaram redução acentuada das lesões gástricas em camundongos tratados com o extrato da planta em todas as doses ensaiadas (10, 100 e 300 mg/kg). Esse efeito pode estar relacionado com a presença de polifenóis, cujo teor encontrado foi 74,3 ± 7,5 µg equivalente de pirogalol/mg do material vegetal examinado e 82,7 ± 7,1 µg equivalente de pirogalol /mg da amostra no extrato preparado por percolação e teor de flavonoides totais, que por sua vez apresentou um resultado de 17,1 ± 1,4 µg/mg de extrato. O extrato apresentou proteção da mucosa gástrica e este efeito pode estar relacionado à presença dos polifenóis e flavonóides encontrados


ABSTRACT Gastro protective activity of the Pavonia alnifolia A.St.-Hil. extract. In Brazil, the Malvaceae family is represented by at about 200 species. Some of those species are known as gastro protective ones. The Pavonia alnifolia A.St.-Hil (Malvaceae) was selected after a chemosystematic approach. The gastro preventive activity of the ethanol extract of stems Pavonia alnifolia was evaluated through the use of the Ethanol:chlroridric acid model on mice. The quantification of the total flavonoids (aluminum chloride method) and total polyphenols (Folin-Ciocalteu method) was also performed since the relation of those components with gastric protection has been previously highlighted. The tests showed a significant reduction of the ulcer formation in the mice treated with the plant extract (10, 100 and 300 mg/kg). This effect may be related to the presence of polyphenols whose content was found to be 74.3 ± 7.5 µg/mg of vegetal material and 82.7 ± 7.1 µg/mg of crude extract and flavonoids, which in turn showed a content of 17.1 ± 1.4 µg/mg dry extract


Asunto(s)
Extractos Vegetales/análisis , Malvaceae/clasificación , Flavonoides/análisis , Polifenoles/análisis
13.
Science ; 346(6207): 1255757, 2014 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-25324399

RESUMEN

The heating of the outer solar atmospheric layers, i.e., the transition region and corona, to high temperatures is a long-standing problem in solar (and stellar) physics. Solutions have been hampered by an incomplete understanding of the magnetically controlled structure of these regions. The high spatial and temporal resolution observations with the Interface Region Imaging Spectrograph (IRIS) at the solar limb reveal a plethora of short, low-lying loops or loop segments at transition-region temperatures that vary rapidly, on the time scales of minutes. We argue that the existence of these loops solves a long-standing observational mystery. At the same time, based on comparison with numerical models, this detection sheds light on a critical piece of the coronal heating puzzle.

14.
Science ; 346(6207): 1255732, 2014 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-25324398

RESUMEN

The solar chromosphere and transition region (TR) form an interface between the Sun's surface and its hot outer atmosphere. There, most of the nonthermal energy that powers the solar atmosphere is transformed into heat, although the detailed mechanism remains elusive. High-resolution (0.33-arc second) observations with NASA's Interface Region Imaging Spectrograph (IRIS) reveal a chromosphere and TR that are replete with twist or torsional motions on sub-arc second scales, occurring in active regions, quiet Sun regions, and coronal holes alike. We coordinated observations with the Swedish 1-meter Solar Telescope (SST) to quantify these twisting motions and their association with rapid heating to at least TR temperatures. This view of the interface region provides insight into what heats the low solar atmosphere.

15.
Eur J Pharm Sci ; 48(4-5): 781-9, 2013 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-23298578

RESUMEN

In order to reach the bloodstream and thus the target receptor, an orally-administered drug must first cross the intestinal barrier, which can occur via a paracellular, passive transcellular, or carrier-mediated uptake and/or efflux process (active or concentration gradient-driven). Our work aimed to explore the transport mechanism of the antiretroviral lamivudine (deoxycytidine nucleoside analogue), using a three-part strategy: in vitro, an ex vivo and an in situ method, represented by PAMPA, rat jejunum patches and rat Single Pass Intestinal Perfusion (SPIP), respectively. The determined permeability coefficients were compared with those from a published Caco-2 and MDCK study. Computational prediction of human jejunal permeability was explored, using various non-human permeability coefficients as descriptors. The ex vivo technique was performed in Franz-type diffusion cells, mounted with male Wistar rat jejunum segment patches. PAMPA was performed with an acceptor solution simulating the binding of serum proteins, an artificial membrane impregnated with egg lecithin/cholesterol and a gradient of pH between donor and acceptor solutions. The SPIP was conducted by proximal jejunum cannulation and drug perfusion in a constant flow rate of 0.2 mL/min. The outcomes of our studies showed the following predicted pattern for lamivudine effective jejunal permeability: P(eff)(exvivoA>B)>P(eff)(SPIP)>P(eff)(exvivo B>A)>P(eff)(Caco-2)≈P(eff)(MDCK)≈P(eff)(PAMPA), strongly suggesting that this compound has carrier-mediated uptake as its dominant transport mechanism. Notwithstanding, Caco-2 cells may indicate an under-expression of uptake transporters and possibly an over-expression efflux transporters, compared to that found in the rat jejunum.


Asunto(s)
Fármacos Anti-VIH/metabolismo , Yeyuno/metabolismo , Lamivudine/metabolismo , Modelos Biológicos , Animales , Transporte Biológico , Humanos , Técnicas In Vitro , Masculino , Perfusión , Permeabilidad , Ratas , Ratas Wistar
16.
Braz J Med Biol Res ; 42(7): 685-91, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19578649

RESUMEN

Nitric oxide (NO) influences renal blood flow mainly as a result of neuronal nitric oxide synthase (nNOS). Nevertheless, it is unclear how nNOS expression is modulated by endogenous angiotensin II, an inhibitor of NO function. We tested the hypothesis that the angiotensin II AT1 receptor and oxidative stress mediated by NADPH oxidase contribute to the modulation of renal nNOS expression in two-kidney, one-clip (2K1C) hypertensive rats. Experiments were performed on male Wistar rats (150 to 170 g body weight) divided into 2K1C (N = 19) and sham-operated (N = 19) groups. nNOS expression in kidneys of 2K1C hypertensive rats (N = 9) was compared by Western blotting to that of 2K1C rats treated with low doses of the AT1 antagonist losartan [10 mg x kg(-1) x day(-1); N = 5] or the superoxide scavenger tempol [0.2 mmol x kg(-1) x day(-1); N = 5], which still remain hypertensive. After 28 days, nNOS expression was significantly increased by 1.7-fold in the clipped kidneys of 2K1C rats and by 3-fold in the non-clipped kidneys of 2K1C rats compared with sham rats, but was normalized by losartan. With tempol treatment, nNOS expression increased 2-fold in the clipped kidneys and 1.4-fold in the non-clipped kidneys compared with sham rats. The changes in nNOS expression were not followed by changes in the enzyme activity, as measured indirectly by the cGMP method. In conclusion, AT1 receptors and oxidative stress seem to be primary stimuli for increased nNOS expression, but this up-regulation does not result in higher enzyme activity.


Asunto(s)
Angiotensina II/fisiología , Hipertensión Renovascular/enzimología , NADPH Oxidasas/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo I/metabolismo , Estrés Oxidativo/efectos de los fármacos , Angiotensina II/antagonistas & inhibidores , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Animales , Óxidos N-Cíclicos/farmacología , Modelos Animales de Enfermedad , Hipertensión Renovascular/fisiopatología , Losartán/farmacología , Masculino , NADPH Oxidasas/fisiología , Estrés Oxidativo/fisiología , Ratas , Ratas Wistar , Marcadores de Spin
17.
Braz. j. med. biol. res ; 42(7): 685-691, July 2009. graf, tab
Artículo en Inglés | LILACS | ID: lil-517800

RESUMEN

Nitric oxide (NO) influences renal blood flow mainly as a result of neuronal nitric oxide synthase (nNOS). Nevertheless, it is unclear how nNOS expression is modulated by endogenous angiotensin II, an inhibitor of NO function. We tested the hypothesis that the angiotensin II AT1 receptor and oxidative stress mediated by NADPH oxidase contribute to the modulation of renal nNOS expression in two-kidney, one-clip (2K1C) hypertensive rats. Experiments were performed on male Wistar rats (150 to 170 g body weight) divided into 2K1C (N = 19) and sham-operated (N = 19) groups. nNOS expression in kidneys of 2K1C hypertensive rats (N = 9) was compared by Western blotting to that of 2K1C rats treated with low doses of the AT1 antagonist losartan (10 mg·kg-1·day-1; N = 5) or the superoxide scavenger tempol (0.2 mmol·kg-1·day-1; N = 5), which still remain hypertensive. After 28 days, nNOS expression was significantly increased by 1.7-fold in the clipped kidneys of 2K1C rats and by 3-fold in the non-clipped kidneys of 2K1C rats compared with sham rats, but was normalized by losartan. With tempol treatment, nNOS expression increased 2-fold in the clipped kidneys and 1.4-fold in the non-clipped kidneys compared with sham rats. The changes in nNOS expression were not followed by changes in the enzyme activity, as measured indirectly by the cGMP method. In conclusion, AT1 receptors and oxidative stress seem to be primary stimuli for increased nNOS expression, but this up-regulation does not result in higher enzyme activity.


Asunto(s)
Animales , Masculino , Ratas , Angiotensina II/fisiología , Hipertensión Renovascular/enzimología , NADPH Oxidasas/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo I/metabolismo , Estrés Oxidativo/efectos de los fármacos , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Angiotensina II/antagonistas & inhibidores , Óxidos N-Cíclicos/farmacología , Modelos Animales de Enfermedad , Hipertensión Renovascular/fisiopatología , Losartán/farmacología , NADPH Oxidasas/fisiología , Estrés Oxidativo/fisiología , Ratas Wistar , Marcadores de Spin
18.
Mol Biotechnol ; 39(2): 89-95, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18327551

RESUMEN

Social and economical development is closely associated with technological innovation and a well-developed biotechnological industry. In the last few years, Brazil's scientific production has been steadily increasing; however, the number of patents is lagging behind, with technological and translational research requiring governmental incentive and reinforcement. The Cell and Molecular Therapy Center (NUCEL) was created to develop activities in the translational research field, addressing concrete problems found in biomedical and veterinary areas and actively searching for solutions by employing a genetic engineering approach to generate cell lines over-expressing recombinant proteins to be transferred to local biotech companies, aiming at furthering the development of a national competence for local production of biopharmaceuticals of widespread use and of life-saving importance. To this end, mammalian cell engineering technologies were used to generate cell lines over-expressing several different recombinant proteins of biomedical and biotechnological interest, namely, recombinant human Amylin/IAPP for diabetes treatment, human FVIII and FIX clotting factors for hemophilia, human and bovine FSH for fertility and reproduction, and human bone repair proteins (BMPs). Expression of some of these proteins is also being sought with the baculovirus/insect cell system (BEVS) which, in many cases, is able to deliver high-yield production of recombinant proteins with biological activity comparable to that of mammalian systems, but in a much more cost-effective manner. Transfer of some of these recombinant products to local Biotech companies has been pursued by taking advantage of the São Paulo State Foundation (FAPESP) and Federal Government (FINEP, CNPq) incentives for joint Research Development and Innovation partnership projects.


Asunto(s)
Biofarmacia , Comunicación Interdisciplinaria , Proteínas Recombinantes/biosíntesis , Transferencia de Tecnología , Amiloide/biosíntesis , Animales , Baculoviridae/metabolismo , Biotecnología , Proteínas Morfogenéticas Óseas/biosíntesis , Brasil , Línea Celular , Factor IX/biosíntesis , Factor VIII/biosíntesis , Hormona Folículo Estimulante/biosíntesis , Ingeniería Genética , Vectores Genéticos/biosíntesis , Humanos , Polipéptido Amiloide de los Islotes Pancreáticos , Investigación/economía , Investigación/organización & administración , Spodoptera/virología
19.
J Eur Acad Dermatol Venereol ; 20(6): 651-6, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16836490

RESUMEN

Though used occasionally, systemic therapies in severe childhood psoriasis have not been systematically investigated. Cyclosporin A (CysA) is effective in adults with severe psoriasis but there are no extensive data regarding the efficacy and safety of its use in childhood psoriasis. In this paper, we describe six children aged between 11 months and 13 years (average: 7.6 years) treated with CysA microemulsion formulation for severe psoriasis, who had been unresponsive to other treatments. The CysA dose ranged from 2 to 4 mg/kg/day, for periods varying from 8 to 105 weeks (mean: 54 weeks). Dose tapering was gradual after lesion improvement and adjusted according to clinical response. Adjuvant therapy with topical steroids, vitamin D3 ointments, coal tar preparations or anthralin was used in all children. Acitretin was used in three patients for short periods. The children were regularly monitored for serum renal and liver function and blood pressure. Improvement of skin lesions was achieved after between 4 and 30 (mean: 12) weeks of treatment, with complete remission in three children. Relapse of lesions occurred in the other children during CysA reduction, but they responded to a dose increase. The treatment was found to be well tolerated and with no significant side-effects. CysA can be used in carefully selected and monitored patients and may represent an alternative tool for severe episodes of psoriasis in children, when other therapies are unsuccessful.


Asunto(s)
Ciclosporina/uso terapéutico , Fármacos Dermatológicos/uso terapéutico , Psoriasis/tratamiento farmacológico , Adolescente , Niño , Preescolar , Ciclosporina/efectos adversos , Fármacos Dermatológicos/efectos adversos , Femenino , Humanos , Lactante , Masculino , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
20.
DNA Cell Biol ; 17(1): 39-49, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9468221

RESUMEN

The rat CYP3A subfamily of cytochrome P450 consists of steroid- and drug-metabolizing enzymes inducible by pregnenolone 16alpha-carbonitrile and by supra-physiological doses of dexamethasone. The induction of CYP3A by dexamethasone has been proposed to be mediated by a mechanism distinct from the glucocorticoid receptor mediated response. However, a synergistic induction of CYP3A has been observed with physiological doses of glucocorticoids and other CYP3A inducers. We have identified the presence of a glucocorticoid-responsive element in the CYP3A1/IGC2 gene that mediates the induction with physiological doses of glucocorticoids. A 219-bp dexamethasone responsive fragment of the CYP3A1/IGC2 gene localized at -2100/-1882 bp upstream of the transcription initiation site was identified in transfection experiments with HepG2 cells. Maximum induction was achieved with 50-100 nM dexamethasone. DNase I footprinting analysis revealed two glucocorticoid receptor-protected sequences in the 5' flank of the CYP3A1/IGC2 gene. Point mutations in footprint I (-1982/-1960-bp) completely abolished binding and transcription activation whereas a mutation in footprint II (-2001/-1986-bp) only decreased the binding and had no effect on transcription activation. These results led to the conclusion that the glucocorticoid response element present in footprint I mediated the dexamethasone response in transfection experiments with HepG2 cells. Pregnenolone 16alpha-carbonitrile failed to induce any transcriptional effect mediated by this response element in the HepG2 cells.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Glucocorticoides/fisiología , Oxigenasas de Función Mixta/genética , Regiones Promotoras Genéticas , Animales , Secuencia de Bases , Citocromo P-450 CYP3A , Huella de ADN , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica , Humanos , Datos de Secuencia Molecular , Ratas , Receptores de Glucocorticoides/fisiología , Eliminación de Secuencia , Transfección , Células Tumorales Cultivadas
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