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281.
282.
S L Pires T S de Assis R N de Almeida J M Filho C Julien I A de Medeiros 《Phytomedicine》2000,7(2):91-98
The acute cardiovascular effects of an aqueous fraction of the ethanolic extract of the leaves (AFL) of Albizia inopinata (Harms) G. P. Lewis (Leguminosae) were studied in rats using a combined in vivo and in vitro approach. In conscious, unrestrained rats, AFL (5, 10 and 20 mg/kg(-1) body wt. i.v., randomly) produced a significant and dose-dependent hypotension associated with increases in heart rate and cardiac output, and with a strong reduction in total peripheral resistances. The hypotensive response to AFL (20 mg/kg(-1) body wt.) was attenuated significantly after nitric oxide (NO) synthase blockade (L-NAME, 20 mg/kg(-1) body wt. i.v.). Furthermore, under these conditions, the associated tachycardia was inhibited completely. In isolated rat aortic rings, increasing concentrations of AFL (10, 20, 40 and 80 microg/ml(-1)) were able to antagonize the effects of phenylephrine- (1 microM) and KCl- (80 mM) induced contractions (IC50 value 65 +/- 4 and 54 +/- 6 microg/ml(-1), respectively). The smooth muscle-relaxant activity of AFL was inhibited similarly either removal of the vascular endothelium or by L-NAME (10 and 100 microM), but was not affected significantly by atropine (1 microM) or indomethacin (10 microM). In isolated rat atrial preparations, AFL (30, 100, 300 and 500 microg/ml(-1)) produced concentration-related negative inotropic and chronotropic effects (IC50 value = 274 +/- 53 and 335 +/- 23 microg/ml(-1), respectively). These results suggest that in rats, the hypotensive effect of AFL is due to a peripheral vasodilation, at least partly secondary to the release of NO by the vascular endothelium. The direct cardio-depressant actions of AFL are of little importance in the systemic effects of the extract. 相似文献
283.
Luísa Mendes-Jorge David Ramos Andreia Valen?a Mariana López-Luppo Virgínia Maria Rico Pires Joana Catita Victor Nacher Marc Navarro Ana Carretero Alfonso Rodriguez-Baeza Jesús Ruberte 《PloS one》2014,9(9)
Iron is essential in the retina because the heme-containing enzyme guanylate cyclase modulates phototransduction in rods and cones. Transferrin endocytosis is the classical pathway for obtaining iron from the blood circulation in the retina. However, the iron storage protein ferritin has been also recently proposed as an iron carrier. In this study, the presence of Scara5 and its binding to L-ferritin was investigated in the retina. Our results showed that Scara5, the specific receptor for L-ferritin, was expressed in mouse and human retinas in many cell types, including endothelial cells. Furthermore, we showed that intravenously injected ferritin crossed the blood retinal barrier through L-ferritin binding to Scara5 in endothelial cells. Thus, suggesting the existence of a new pathway for iron delivery and trafficking in the retina. In a murine model of photoreceptor degeneration, Scara5 was downregulated, pointing out this receptor as a potential player implicated in retinopathy and also as a possible therapeutic target. 相似文献
284.
Santos Gabriella Sousa Sinoti Simone Batista Pires de Almeida Fabrício Tavares Cunha Silveira Dâmaris Simeoni Luiz Alberto Gomes-Copeland Kicia Karinne Pereira 《Plant Cell, Tissue and Organ Culture》2020,143(1):13-29
Plant Cell, Tissue and Organ Culture (PCTOC) - Galantamine is an alkaloid in the Amaryllidaceae family widely used in the treatment of Alzheimer's disease. Since its approval for clinical use... 相似文献
285.
Makenzie E. Mabry Julia M. Brose Paul D. Blischak Brittany Sutherland Wade T. Dismukes Christopher A. Bottoms Patrick P. Edger Jacob D. Washburn Hong An Jocelyn C. Hall Michael R. McKain Ihsan Al-Shehbaz Michael S. Barker M. Eric Schranz Gavin C. Conant J. Chris Pires 《American journal of botany》2020,107(8):1148-1164
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287.
The ability of Cynara cardunculus L. protease to perform peptide synthesis was investigated using an aqueous organic biphasic system and the amino acid derivatives CBZ.Phe and Met.OMe. The reaction products were separated by RP-HPLC and identified by amino acid analysis and by EI-MS. Significant amounts of the dipeptide CBZ.Phe.Met.OMe was produced within 24h by Cynara cardunculus L. protease as compared with the amount produced by pepsin under the same conditions. 相似文献
288.
Christiane Maria Ayo Ana Vitória da Silveira Camargo Fábio Batista Frederico Rubens Camargo Siqueira Mariana Previato Fernando Henrique Antunes Murata Aparecida Perpétuo Silveira-Carvalho Amanda Pires Barbosa Cinara de Cássia Brand?o de Mattos Luiz Carlos de Mattos 《PloS one》2015,10(12)
This study investigated whether polymorphisms of the MICA (major histocompatibility complex class I chain-related gene A) gene are associated with eye lesions due to Toxoplasma gondii infection in a group of immunocompetent patients from southeastern Brazil. The study enrolled 297 patients with serological diagnosis of toxoplasmosis. Participants were classified into two distinct groups after conducting fundoscopic exams according to the presence (n = 148) or absence (n = 149) of ocular scars/lesions due to toxoplasmosis. The group of patients with scars/lesions was further subdivided into two groups according to the type of the ocular manifestation observed: primary (n = 120) or recurrent (n = 28). Genotyping of the MICA and HLA alleles was performed by the polymerase chain reaction-sequence specific oligonucleotide technique (PCR-SSO; One Lambda®) and the MICA-129 polymorphism (rs1051792) was identified by nested polymerase chain reaction (PCR-RFLP). Significant associations involving MICA polymorphisms were not found. Although the MICA*002~HLA-B*35 haplotype was associated with increased risk of developing ocular toxoplasmosis (P-value = 0.04; OR = 2.20; 95% CI = 1.05–4.60), and the MICA*008~HLA-C*07 haplotype was associated with protection against the development of manifestations of ocular toxoplasmosis (P-value = 0.009; OR: 0.44; 95% CI: 0.22–0.76), these associations were not statistically significant after adjusting for multiple comparisons. MICA polymorphisms do not appear to influence the development of ocular lesions in patients diagnosed with toxoplasmosis in this study population. 相似文献
289.
290.
Priscila Oliveira dos Santos Anderson Messias Rodrigues Geisa Ferreira Fernandes Silvia Helena Marques da Silva Eva Burger Zoilo Pires de Camargo 《PLoS neglected tropical diseases》2015,9(2)