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1.
Sci Rep ; 14(1): 2155, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38272959

RESUMO

In animal communication, functionally referential alarm calls elicit the same behavioral responses as their referents, despite their typically distinct bioacoustic traits. Yet the auditory forebrain in at least one songbird species, the black-capped chickadee Poecile atricapillus, responds similarly to threat calls and their referent predatory owl calls, as assessed by immediate early gene responses in the secondary auditory forebrain nuclei. Whether and where in the brain such perceptual and cognitive equivalence is processed remains to be understood in most other avian systems. Here, we studied the functional neurogenomic (non-) equivalence of acoustic threat stimuli perception by the red-winged blackbird Agelaius phoeniceus in response to the actual calls of the obligate brood parasitic brown-headed cowbird Molothrus ater and the referential anti-parasitic alarm calls of the yellow warbler Setophaga petechia, upon which the blackbird is known to eavesdrop. Using RNA-sequencing from neural tissue in the auditory lobule (primary and secondary auditory nuclei combined), in contrast to previous findings, we found significant differences in the gene expression profiles of both an immediate early gene, ZENK (egr-1), and other song-system relevant gene-products in blackbirds responding to cowbird vs. warbler calls. In turn, direct cues of threats (including conspecific intruder calls and nest-predator calls) elicited higher ZENK and other differential gene expression patterns compared to harmless heterospecific calls. These patterns are consistent with a perceptual non-equivalence in the auditory forebrain of adult male red-winged blackbirds in response to referential calls and the calls of their referents.


Assuntos
Passeriformes , Aves Canoras , Animais , Masculino , Vocalização Animal/fisiologia , Aves Canoras/fisiologia , Prosencéfalo/fisiologia , Transcriptoma , Percepção Auditiva/fisiologia
2.
Food Chem Toxicol ; 151: 112095, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33689855

RESUMO

Skin cancer is a public health problem due to its high incidence. Ultraviolet radiation (UVR) is the main etiological agent of this disease. Photochemoprotection involves the use of substances to avoid damage caused by UV exposure. The aim of this work was to determine the phytochemical fingerprint and photochemoprotective effect against UVB radiation-induced skin damage such as erythema and carcinogenesis of H. mociniana methanolic extract (MEHm). The chemical composition of the MEHm was analysed by LC/ESI-MS/MS. Three quercetin derivatives, two pectinolides, and two caffeic acid derivatives were identified in the methanolic extract. MEHm has antioxidant effect and it is not cytotoxic in HaCaT cells. Phytochemicals from H. mociniana have a photochemopreventive effect because they absorb UV light and protect HaCaT cells from UVR-induced cell death. Also, in SKH-1 mice -acute exposure-, it decreased erythema formation, modulating the inflammatory response, reduced the skin damage according to histological analysis and diminished p53 expression. Finally, MEHm protects from photocarcinogenesis by reducing the incidence and multiplicity of skin carcinomas in SKH-1 mice exposed chronically to UVB radiation.


Assuntos
Eritema/prevenção & controle , Hyptis/química , Neoplasias Induzidas por Radiação/prevenção & controle , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Protetores contra Radiação/farmacologia , Neoplasias Cutâneas/prevenção & controle , Raios Ultravioleta , Animais , Carcinogênese/efeitos dos fármacos , Linhagem Celular , Eritema/etiologia , Feminino , Humanos , Camundongos , Camundongos Pelados , Neoplasias Cutâneas/patologia
3.
Nat Biotechnol ; 18(10): 1055-9, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11017042

RESUMO

Here we describe a procedure for cloning pigs by the use of in vitro culture systems. Four healthy male piglets from two litters were born following nuclear transfer of cultured somatic cells and subsequent embryo transfer. The initiation of five additional pregnancies demonstrates the reproducibility of this procedure. Its important features include extended in vitro culture of fetal cells preceding nuclear transfer, as well as in vitro maturation and activation of oocytes and in vitro embryo culture. The cell culture and nuclear transfer techniques described here should allow the use of genetic modification procedures to produce tissues and organs from cloned pigs with reduced immunogenicity for use in xenotransplantation.


Assuntos
Clonagem de Organismos/métodos , Suínos/embriologia , Suínos/genética , Animais , Contagem de Células , Diferenciação Celular , Núcleo Celular/genética , Núcleo Celular/metabolismo , Células Cultivadas , Técnicas de Cultura , DNA/análise , DNA/genética , Transferência Embrionária , Feminino , Fertilização in vitro , Feto/citologia , Feto/metabolismo , Humanos , Masculino , Repetições de Microssatélites/genética , Oócitos/citologia , Oócitos/metabolismo , Gravidez , Reprodutibilidade dos Testes , Transfecção , Transplante Heterólogo
4.
Am J Crit Care ; 6(2): 127-31, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9172849

RESUMO

BACKGROUND: Cardiopulmonary bypass can increase pulmonary vascular tone and decrease ventilation-perfusion matching by impairing the pulmonary endothelial production of nitric oxide. OBJECTIVES: We tested the hypothesis that inhalation of exogenous nitric oxide decreases the ratio of mean pulmonary arterial pressure to mean system arterial pressure and the intrapulmonary shunt fraction and increases the ratio of arterial blood oxygen tension to fraction of inspired oxygen in patients in whom the ratio of mean pulmonary arterial pressure to mean systemic arterial pressure is more than 0.50, and the ratio of arterial blood oxygen tension to fraction of inspired oxygen is less than 300 mm Hg in the first 24 hours after cardiopulmonary bypass surgery. METHODS: Only those patients who had estimates of the ratio of mean pulmonary arterial pressure to mean systemic arterial pressure and the ratio of arterial blood oxygen tension to fraction of inspired oxygen determined preoperatively were enrolled. Hemodynamic variables were recorded, and blood samples were obtained for oximetric analysis 5 minutes before and 30 minutes after inhalation of nitric oxide began. The concentration of nitric oxide inhaled was maintained at 20 parts per million. The data were analyzed by using Friedman's repeated measures analysis of variance. RESULTS: Thirteen patients were enrolled in the study. The mean preoperative ratio of mean pulmonary arterial pressure to mean systemic arterial pressure was 0.63 +/- 0.08 (standard error of the mean), and the mean preoperative ratio of arterial blood oxygen tension to fraction of inspired oxygen was 131 +/- 15 mm Hg. No differences between preoperative and postoperative values were detected. Inhalation of nitric oxide decreased the ratio of mean pulmonary arterial pressure to mean systemic arterial from 0.53 +/- 0.07 to 0.39 +/- 0.5 and increased the ratio of arterial blood oxygen tension to fraction of inspired oxygen from 167 +/- 35 mm Hg to 235 +/- 45 mm Hg. Inhalation of nitric oxide also decreased the intrapulmonary shunt fraction from 0.29 +/- 0.05 to 0.19 +/- 0.04. CONCLUSIONS: Inhalation of nitric oxide selectively decreases pulmonary vascular tone and increases ventilation-perfusion matching in patients with persistent pulmonary hypertension and hypoxemia after surgery requiring cardiopulmonary bypass. Inhalation of nitric oxide may be a valuable adjunctive therapy for these patients.


Assuntos
Ponte Cardiopulmonar , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão/tratamento farmacológico , Óxido Nítrico/uso terapêutico , Administração por Inalação , Adolescente , Adulto , Artérias , Criança , Pré-Escolar , Hemodinâmica/efeitos dos fármacos , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Oxigênio/sangue , Período Pós-Operatório , Resistência Vascular/efeitos dos fármacos , Relação Ventilação-Perfusão/efeitos dos fármacos
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