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1.
Int J Mol Sci ; 24(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38069161

RESUMO

The angiotensin II type 2 (AT2) receptor has a role in promoting insulin sensitivity. However, the mechanisms underlying the AT2 receptor-induced facilitation of insulin are still not completely understood. Therefore, we investigated whether acute in vivo administration of AT2 receptor agonist compound 21 (C21) could activate insulin signaling molecules in insulin-target tissues. We report that, in male C57BL/6 mice, an acute (5 min, 0.25 mg/kg; i.v.) injection of C21 induces the phosphorylation of Akt and ERK1/2 at activating residues (Ser473 and Thr202/Tyr204, respectively) in both epididymal white adipose tissue (WAT) and heart tissue. In WAT, the extent of phosphorylation (p) of Akt and ERK1/2 induced by C21 was approximately 65% of the level detected after a bolus injection of a dose of insulin known to induce maximal activation of the insulin receptor (IR). In the heart, C21 stimulated p-Akt to a lesser extent than in WAT and stimulated p-ERK1/2 to similar levels to those attained by insulin administration. C21 did not modify p-IR levels in either tissue. We conclude that in vivo injection of the AT2 receptor agonist C21 activates Akt and ERK1/2 through a mechanism that does not involve the IR, indicating the participation of these enzymes in AT2R-mediated signaling.


Assuntos
Insulinas , Proteínas Proto-Oncogênicas c-akt , Camundongos , Animais , Masculino , Fosforilação , Sistema de Sinalização das MAP Quinases , Camundongos Endogâmicos C57BL , Tecido Adiposo/metabolismo , Receptor Tipo 2 de Angiotensina/metabolismo
2.
Agora USB ; 23(1)jun. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1533571

RESUMO

La formación docente, la investigación educativa, las relaciones pedagógicas y el saber articulan una compleja discusión que, en particular, pueden estar mediada por la "narrativa pedagógica"; es decir, un método que nos ayuda en la indagación por la acción docente y la experiencia "pedagógica", como crisis que se abre, profundiza, pero no se resuelve". Esto con el fin de descubrir interrogantes que nos conduzca a potenciales producciones "colaborativa[s] de saber pedagógico, la reconstrucción de la memoria pedagógica de la escuela y la transformación de las prácticas educativas" (Suárez, 2011, p. 17). Este dispositivo de transformación centra su atención en los relatos de experiencia docente que pregunta, relacionan, participan, focalizan y construyen estrategias para la indagación y reflexión a través de las narrativas.


Teacher training, educational research, pedagogical relations, and knowledge articulate a complex discussion that, in particular, can be mediated by the "pedagogical narrative;" that is to say, a method that helps us in the inquiry into the teaching action and the pedagogical experience. This in order to discover questions that lead us to potential "collaborative" productions of pedagogical knowledge, the reconstruction of the pedagogical memory of the school, and the transformation of educational practices (Suárez, 2011, p. 17). This transformation device focuses its attention on the accounts of teaching experience that question, relate, participate, focus, and build strategies for inquiry and reflection through narratives.

3.
Nat Prod Bioprospect ; 13(1): 9, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36939940

RESUMO

The Genisteae tribe belongs to the Fabaceae family. The wide occurrence of secondary metabolites, explicitly highlighting the quinolizidine alkaloids (QAs), characterizes this tribe. In the present study, twenty QAs (1-20), including lupanine (1-7), sparteine (8-10), lupanine (11), cytisine and tetrahydrocytisine (12-17), and matrine (18-20)-type QAs were extracted and isolated from leaves of three species (i.e., Lupinus polyphyllus ('rusell' hybrid), Lupinus mutabilis, and Genista monspessulana) belonging to the Genisteae tribe. These plant sources were propagated under greenhouse conditions. The isolated compounds were elucidated by analyzing their spectroscopical data (MS, NMR). The antifungal effect on the mycelial growth of Fusarium oxysporum (Fox) of each isolated QA was then evaluated through the amended medium assay. The best antifungal activity was found to be for compounds 8 (IC50 = 16.5 µM), 9 (IC50 = 7.2 µM), 12 (IC50 = 11.3 µM), and 18 (IC50 = 12.3 µM). The inhibitory data suggest that some QAs could efficiently inhibit Fox mycelium growth depending on particular structural requirements deduced from structure-activity relationship scrutinies. The identified quinolizidine-related moieties can be involved in lead structures to develop further antifungal bioactives against Fox.

4.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1536163

RESUMO

Una serie de amidas N-alquilsustituidas 1-16 fueron sintetizadas a partir de malonato de dietilo y ésteres de alquilo derivados de los aminoácidos L-triptófano, L-alanina, L-fenilalanina y L-tirosina. Los métodos de síntesis empleados involucraron calentamiento por irradiación de microondas empleando tanto un ácido de Lewis (AlCl3) o 4-dimetilaminopiridina (DMAP) como catalizador y auxiliar nucleofílico, respectivamente. Los resultados sugieren que el uso de irradiación de microondas y de DMAP conlleva mejores rendimientos en un tiempo de reacción más corto. Para ilustrar las diferencias observadas, se presentan las propuestas mecanísticas de cada método de reacción para la formación de amidas N-alquilsustituidas. Finalmente, las amidas sintetizadas se evaluaron en condiciones in vitro frente a Fusarium oxysporum; mostraron actividad antifúngica a diferentes niveles (0,40 mM < IC50 < 29,1 mM), lo cual indicó que las variaciones de la actividad observada de este grupo de compuestos pueden deberse al efecto de la amida acíclica como bioisóstero no clásico de algunas fitoalexinas heterocíclicas.


N-alkyl substituted amides 1-16 were synthesized from diethyl malonate and alkyl esters derived from the amino acids L -tryptophan, L -alanine, L -phenylalanine, and L -tyrosine. In addition, a microwave-assisted protocol was employed using a Lewis acid (AlCl3) or dimethylaminopyridine (DMAP) as a catalyst and nucleophilic auxiliary, respectively, affording the desired compounds. The results suggest that DMAP-catalyzed reactions under microwave irradiation yield higher during short reaction times. Each reaction method's mechanistic proposals for forming N-alkyl-substituted amides are presented to illustrate the observed differences. The synthesized amides were evaluated under in vitro conditions against Fusarium oxysporum. The compounds exhibited antifungal activity at different levels (0.40 mM < IC50 < 29.1 mM). These results indicated that the observed activity variations of this compound group might be due to the effect of acyclic amide as a non-classical bioisostere of some heterocyclic phytoalexins.


Uma série de amidas N-alquil substituídas foram sintetizadas a partir de malonato de dietila e ésteres alquílicos derivados dos aminoácidos ʟ-triptofano, L -alanina, L-fenilalanina e L-tirosina. Os métodos de síntese empregados foram realizados usando aquecimento por irradiação de micro-ondas empregando um ácido de Lewis (AlCl3) ou dimetilaminopiridina (DMAP) como catalisador. Os resultados sugerem que a irradiação de micro-ondas usando DMAP leva a melhores rendimentos em um tempo de reação mais curto. Para ilustrar as diferenças observadas, são apresentadas as propostas mecanísticas de cada método de reação para a formação de amidas N-alquilsubstituídas. Finalmente, as amidas sintetizadas foram avaliadas in vitro contra Fusarium oxysporum, mostrando atividade antifúngica em diferentes níveis (0.40 mM < IC50 < 29.1 mM), o que indica que as variações observadas na atividade desse grupo de compostos podem ser devidas ao efeito de amida acíclica como um bioisóstero não clássico de algumas fitoalexinas heterocíclicas.

5.
Molecules ; 27(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35011535

RESUMO

Fusarium oxysporum is an aggressive phytopathogen that affects various plant species, resulting in extensive local and global economic losses. Therefore, the search for competent alternatives is a constant pursuit. Quinolizidine alkaloids (QA) are naturally occurring compounds with diverse biological activities. The structural diversity of quinolizidines is mainly contributed by species of the family Fabaceae, particularly the genus Lupinus. This quinolizidine-based chemo diversity can be explored to find antifungals and even mixtures to address concomitant effects on F. oxysporum. Thus, the antifungal activity of quinolizidine-rich extracts (QREs) from the leaves of eight greenhouse-propagated Lupinus species was evaluated to outline promising QA mixtures against F. oxysporum. Thirteen main compounds were identified and quantified using an external standard. Quantitative analysis revealed different contents per quinolizidine depending on the Lupinus plant, ranging from 0.003 to 32.8 mg/g fresh leaves. Bioautography showed that all extracts were active at the maximum concentration (5 µg/µL). They also exhibited >50% mycelium growth inhibition. All QREs were fungistatic except for the fungicidal QRE of L. polyphyllus Lindl. Angustifoline, matrine, 13α-hydroxylupanine, and 17-oxolupanine were ranked to act jointly against the phytopathogen. Our findings constitute reference information to better understand the antifungal activity of naturally afforded QA mixtures from these globally important plants.


Assuntos
Antifúngicos/farmacologia , Lupinus/química , Extratos Vegetais/farmacologia , Quinolizidinas/farmacologia , Antifúngicos/química , Cromatografia Gasosa-Espectrometria de Massas , Efeito Estufa , Lupinus/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Quinolizidinas/química
6.
Agora USB ; 19(2): 537-546, jul.-dic. 2019.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1054794

RESUMO

Resumen El proyecto de la naturaleza y el proyecto del conocimiento han sido intervenidos por la razón como instrumento de la acumulación de la riqueza y el poder. La hermana naturaleza, a la cual pertenecemos, ha sido convertida en recursos extraíbles y utilizables, no como bienes de uso para un mejor vivir, sino como valor de cambio al servicio de la acumulación del capital, de allí su deterioro (y el nuestro). Ahora bien, si es la razón de la producción para el mercado, la que condujo al deterioro ambiental y a la fragmentación del saber y a la valoración ciega de lo instrumental como conocimiento prevalente, bien vale hacer un alto en el camino y, en las casas del saber, volver a pensar en libertad dos puntos nodales: el equilibrio de la naturaleza y el desarrollo del saber para la emancipación.


Abstract The project of nature and the project of knowledge have been intervened for reason as an instrument of the accumulation of wealth and power. Sister nature, to which we belong, has been converted into removable and usable resources, not as goods of use for a better living, but as a value of exchange at the service of the accumulation of capital. Hence, its deterioration (and ours). However, if it is the reason for the production for the market, which led to environmental deterioration and fragmentation of knowledge, and the blind assessment of the instrumental as prevalent knowledge, it is good to make a stop on the way. In addition, in the houses of knowledge, to rethink two nodal points in freedom: the balance of nature and the development of knowledge for emancipation.

7.
Sci Total Environ ; 690: 1203-1217, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31470483

RESUMO

The unregulated oil exploitation in the Northern Ecuadorian Amazon Region (NEAR), mainly from 1964 to the 90's, led to toxic compounds largely released into the environment. A large majority of people living in the Amazon region have no access to drinking water distribution systems and collects water from rain, wells or small streams. The concentrations of major ions, trace elements, PAHs (polycyclic aromatic hydrocarbons) and BTEX (benzene, toluene, ethylbenzene, xylenes) were analyzed in different water sources to evaluate the impacts of oil extraction and refining. Samples were taken from the NEAR and around the main refinery of the country (Esmeraldas Oil Refinery/State Oil Company of Ecuador) and were compared with domestic waters from the Southern region, not affected by petroleum activities. In most of the samples, microbiological analysis revealed a high level of coliforms representing significant health risks. All measured chemical compounds in waters were in line with national and international guidelines, except for manganese, zinc and aluminum. In several deep-water wells, close to oil camps, toluene concentrations were higher than the natural background while PAHs concentrations never exceeded individually 2 ng·L-1. Water ingestion represented 99% of the total exposure pathways for carcinogenic and non-carcinogenic elements (mainly zinc) in adults and children, while 20% to 49% of the Total Cancer Risk was caused by arsenic concentrations. The health index (HI) indicates acceptable chronic effects for domestic use according the US-EPA thresholds. Nevertheless, these limits do not consider the cocktail effects of metallic and organic compounds. Furthermore, they do not include the social determinants of human exposure, such as socio-economic living conditions or vulnerability. Most (72%) of interviewed families knew sanitary risks but a discrepancy was observed between knowledge and action: religious beliefs, cultural patterns, information sources, experience and emotions play an important role front to exposure.


Assuntos
Água Potável/química , Exposição Ambiental/análise , Poluição por Petróleo/estatística & dados numéricos , Percepção Social , Poluição da Água/estatística & dados numéricos , Equador , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Humanos , Compostos Orgânicos , Poluição por Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos , Rios , Poluentes Químicos da Água , Poluição da Água/análise , Qualidade da Água
8.
Physiol Rep ; 6(16): e13824, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30156060

RESUMO

The renin-angiotensin system modulates insulin action. Angiotensin type 1 receptor exerts a deleterious effect, whereas the angiotensin type 2 receptor (AT2R) appears to have beneficial effects providing protection against insulin resistance and type 2 diabetes. To further explore the role of the AT2R on insulin action and glucose homeostasis, in this study we administered C57Bl/6 mice with the synthetic agonist of the AT2R C21 for 12 weeks (1 mg/kg per day; ip). Vehicle-treated animals were used as control. Metabolic parameters, glucose, and insulin tolerance, in vivo insulin signaling in main insulin-target tissues as well as adipose tissue levels of adiponectin, and TNF-α were assessed. C21-treated animals displayed decreased glycemia together with unaltered insulinemia, increased insulin sensitivity, and increased glucose tolerance compared to nontreated controls. This was accompanied by a significant decrease in adipocytes size in epididymal adipose tissue and significant increases in both adiponectin and UCP-1 expression in this tissue. C21-treated mice showed an increase in both basal Akt and ERK1/2 phosphorylation levels in the liver, and increased insulin-stimulated Akt activation in adipose tissue. This positive modulation of insulin action induced by C21 appeared not to involve the insulin receptor. In C21-treated mice, adipose tissue and skeletal muscle became unresponsive to insulin in terms of ERK1/2 phosphorylation levels. Present data show that chronic pharmacological activation of AT2R with C21 increases insulin sensitivity in mice and indicate that the AT2R has a physiological role in the conservation of insulin action.


Assuntos
Resistência à Insulina/fisiologia , Receptor Tipo 2 de Angiotensina/agonistas , Sulfonamidas/farmacologia , Tiofenos/farmacologia , Adipócitos/efeitos dos fármacos , Adiponectina/metabolismo , Tecido Adiposo/metabolismo , Animais , Glicemia/metabolismo , Tamanho Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Esquema de Medicação , Avaliação Pré-Clínica de Medicamentos/métodos , Teste de Tolerância a Glucose , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Receptor Tipo 2 de Angiotensina/fisiologia , Transdução de Sinais , Sulfonamidas/administração & dosagem , Tiofenos/administração & dosagem , Fator de Necrose Tumoral alfa/metabolismo
9.
Epilepsy Res ; 140: 184-191, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29414526

RESUMO

OBJECTIVE: Focal cortical dysplasia (FCD) is a common pathology in focal drug resistant epilepsy (DRE). Voxel based morphometric MRI analysis has been proposed as an adjunct to visual detection of FCD, which remains challenging given the subtle radiographic appearance of FCD. This study evaluates the diagnostic value of morphometric analysis program (MAP) in focal DRE with pathology-confirmed FCD. METHODS: Automated morphometric analysis program analysis generated z-score maps derived from T1 images, referenced to healthy adult or pediatric controls for each of 39 cases with pathology-confirmed FCD. MAP identified abnormal extension of gray matter into white matter (MAP-E) and blurring of the gray-white matter junction (MAP-J), independently of clinical data and other imaging modalities. MRI was visually reviewed by neuroradiologists as part of usual clinical care, and independently re-reviewed retrospectively by a neuroradiologist with >10-years' experience in epilepsy MRI. Sensitivity and specificity were calculated for MRI, MAP, scalp-EEG, PET and SISCOM compared to resection area (RA). RESULTS: In this cohort of 39 histologically proven FCD cases, the sensitivity and specificity of MAP-J [64% (95% CI 48%-77%) and 96% (95% CI 93%-0.98%)] and MAP-E [74% (95% CI 59%-86%) and 94% (95% CI 91%-97%)] were higher than qualitative MRI review, SISCOM, and FDG-PET. Initial MRI review detected FCD in 17, expert review identified 26. Among cases not detected by initial MRI review, MAP-J correctly identified FCD in 12 additional cases and MAP-E in 13 cases. Among cases not detected by expert MRI review, MAP-J correctly identified 6 and MAP-E 8 cases. Excellent surgical outcome was achieved in 76% of patients. SIGNIFICANCE: MAP showed favorable sensitivity compared to visual inspection and other non-invasive imaging modalities. MAP complements non-invasive imaging evaluation for detection of FCD in focal DRE patients.


Assuntos
Encéfalo/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Adolescente , Adulto , Encéfalo/cirurgia , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/cirurgia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Malformações do Desenvolvimento Cortical/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Substância Branca/diagnóstico por imagem , Substância Branca/cirurgia , Adulto Jovem
10.
PLoS One ; 12(8): e0183278, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28813513

RESUMO

Mas receptor (MasR) is a G protein-coupled receptor proposed as a candidate for mediating the angiotensin (Ang)-converting enzyme 2-Ang (1-7) protective axis of renin-angiotensin system. Because the role of this receptor is not definitively clarified, determination of MasR tissue distribution and expression levels constitutes a critical knowledge to fully understanding its function. Commercially available antibodies have been widely employed for MasR protein localization and quantification, but they have not been adequately validated. In this study, we carried on an exhaustive evaluation of four commercial MasR antibodies, following previously established criteria. Western Blotting (WB) and immunohistochemistry studies starting from hearts and kidneys from wild type (WT) mice revealed that antibodies raised against different MasR domains yielded different patterns of reactivity. Furthermore, staining patterns appeared identical in samples from MasR knockout (MasR-KO) mice. We verified by polymerase chain reaction analysis that the MasR-KO mice used were truly deficient in this receptor as MAS transcripts were undetectable in either heart or kidney from this animal model. In addition, we evaluated the ability of the antibodies to detect the human c-myc-tagged MasR overexpressed in human embryonic kidney cells. Three antibodies were capable of detecting the MasR either by WB or by immunofluorescence, reproducing the patterns obtained with an anti c-myc antibody. In conclusion, although three of the selected antibodies were able to detect MasR protein at high expression levels observed in a transfected cell line, they failed to detect this receptor in mice tissues at physiological expression levels. As a consequence, validated antibodies that can recognize and detect the MasR at physiological levels are still lacking.


Assuntos
Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Anticorpos/metabolismo , Western Blotting , Linhagem Celular , Imunofluorescência , Células HEK293 , Humanos , Imuno-Histoquímica , Rim/metabolismo , Camundongos , Camundongos Knockout , Miocárdio/metabolismo , Proto-Oncogene Mas , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Crit Care Med ; 45(7): e674-e682, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28406812

RESUMO

OBJECTIVE: The prognostic role of electroencephalography during and after targeted temperature management in postcardiac arrest patients, relatively to other predictors, is incompletely known. We assessed performances of electroencephalography during and after targeted temperature management toward good and poor outcomes, along with other recognized predictors. DESIGN: Cohort study (April 2009 to March 2016). SETTING: Two academic hospitals (Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland; Mayo Clinic, Rochester, MN). PATIENTS: Consecutive comatose adults admitted after cardiac arrest, identified through prospective registries. INTERVENTIONS: All patients were managed with targeted temperature management, receiving prespecified standardized clinical, neurophysiologic (particularly, electroencephalography during and after targeted temperature management), and biochemical evaluations. MEASUREMENTS AND MAIN RESULTS: We assessed electroencephalography variables (reactivity, continuity, epileptiform features, and prespecified "benign" or "highly malignant" patterns based on the American Clinical Neurophysiology Society nomenclature) and other clinical, neurophysiologic (somatosensory-evoked potential), and biochemical prognosticators. Good outcome (Cerebral Performance Categories 1 and 2) and mortality predictions at 3 months were calculated. Among 357 patients, early electroencephalography reactivity and continuity and flexor or better motor reaction had greater than 70% positive predictive value for good outcome; reactivity (80.4%; 95% CI, 75.9-84.4%) and motor response (80.1%; 95% CI, 75.6-84.1%) had highest accuracy. Early benign electroencephalography heralded good outcome in 86.2% (95% CI, 79.8-91.1%). False positive rates for mortality were less than 5% for epileptiform or nonreactive early electroencephalography, nonreactive late electroencephalography, absent somatosensory-evoked potential, absent pupillary or corneal reflexes, presence of myoclonus, and neuron-specific enolase greater than 75 µg/L; accuracy was highest for early electroencephalography reactivity (86.6%; 95% CI, 82.6-90.0). Early highly malignant electroencephalography had an false positive rate of 1.5% with accuracy of 85.7% (95% CI, 81.7-89.2%). CONCLUSIONS: This study provides class III evidence that electroencephalography reactivity predicts both poor and good outcomes, and motor reaction good outcome after cardiac arrest. Electroencephalography reactivity seems to be the best discriminator between good and poor outcomes. Standardized electroencephalography interpretation seems to predict both conditions during and after targeted temperature management.


Assuntos
Coma/etiologia , Eletroencefalografia , Parada Cardíaca/complicações , Parada Cardíaca/fisiopatologia , Idoso , Biomarcadores , Feminino , Parada Cardíaca/mortalidade , Parada Cardíaca/terapia , Humanos , Hipotermia Induzida , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
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