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81.
Anti‐HSV‐1 and HSV‐2 Flavonoids and a New Kaempferol Triglycoside from the Medicinal Plant Kalanchoe daigremontiana 下载免费PDF全文
Fernanda Gouvêa Gomes Ürményi Georgia do Nascimento Saraiva Livia Marques Casanova Amanda dos Santos Matos Luiza Maria de Magalhães Camargo Maria Teresa Villela Romanos Sônia Soares Costa 《化学与生物多样性》2016,13(12):1707-1714
Kalanchoe daigremontiana (Crassulaceae) is a medicinal plant native to Madagascar. The aim of this study was to investigate the flavonoid content of an aqueous leaf extract from K. daigremontiana (Kd), and assess its antiherpetic potential. The major flavonoid, kaempferol 3‐O‐β‐d ‐xylopyranosyl‐(1 → 2)‐α‐l ‐rhamnopyranoside ( 1 ), was isolated from the AcOEt fraction (Kd‐AC). The BuOH‐soluble fraction afforded quercetin 3‐O‐β‐d ‐xylopyranosyl‐(1 → 2)‐α‐l ‐rhamnopyranoside ( 2 ) and the new kaempferol 3‐O‐β‐d ‐xylopyranosyl‐(1 → 2)‐α‐l ‐rhamnopyranoside‐7‐O‐β‐d ‐glucopyranoside ( 3 ), named daigremontrioside. The crude extract, Kd‐AC fraction, flavonoids 1 and 2 were evaluated using acyclovir‐sensitive strains of HSV‐1 and HSV‐2. Kd‐AC was highly active against HSV‐1 (EC50 = 0.97 μg/ml, SI > 206.1) and HSV‐2 (EC50 = 0.72 μg/ml, SI > 277.7). Flavonoids 1 and 2 showed anti‐HSV‐1 (EC50 = 7.4 μg/ml; SI > 27 and EC50 = 5.8 μg/ml; SI > 8.6, respectively) and anti‐HSV‐2 (EC50 = 9.0 μg/ml; SI > 22.2 and EC50 = 36.2 μg/ml; SI > 5.5, respectively) activities, suggesting the contribution of additional substances to the antiviral activity. 相似文献
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Daphne van Geemen Ana L. F. Soares Pim J. A. Oomen Anita Driessen-Mol Marloes W. J. T. Janssen-van den Broek Antoon J. van den Bogaerdt Ad J. J. C. Bogers Marie-José T. H. Goumans Frank P. T. Baaijens Carlijn V. C. Bouten 《PloS one》2016,11(2)
There is limited information about age-specific structural and functional properties of human heart valves, while this information is key to the development and evaluation of living valve replacements for pediatric and adolescent patients. Here, we present an extended data set of structure-function properties of cryopreserved human pulmonary and aortic heart valves, providing age-specific information for living valve replacements. Tissue composition, morphology, mechanical properties, and maturation of leaflets from 16 pairs of structurally unaffected aortic and pulmonary valves of human donors (fetal-53 years) were analyzed. Interestingly, no major differences were observed between the aortic and pulmonary valves. Valve annulus and leaflet dimensions increase throughout life. The typical three-layered leaflet structure is present before birth, but becomes more distinct with age. After birth, cell numbers decrease rapidly, while remaining cells obtain a quiescent phenotype and reside in the ventricularis and spongiosa. With age and maturation–but more pronounced in aortic valves–the matrix shows an increasing amount of collagen and collagen cross-links and a reduction in glycosaminoglycans. These matrix changes correlate with increasing leaflet stiffness with age. Our data provide a new and comprehensive overview of the changes of structure-function properties of fetal to adult human semilunar heart valves that can be used to evaluate and optimize future therapies, such as tissue engineering of heart valves. Changing hemodynamic conditions with age can explain initial changes in matrix composition and consequent mechanical properties, but cannot explain the ongoing changes in valve dimensions and matrix composition at older age. 相似文献
83.
Paula M. Nogueira Rafael R. Assis Ana C. Torrecilhas Elvira M. Saraiva Natália L. Pessoa Marco A. Campos Eric F. Marialva Cláudia M. Ríos-Velasquez Felipe A. Pessoa Nágila F. Secundino Jer?nimo N. Rugani Elsa Nieves Salvatore J. Turco Maria N. Melo Rodrigo P. Soares 《PLoS neglected tropical diseases》2016,10(8)
The immunomodulatory properties of lipophosphoglycans (LPG) from New World species of Leishmania have been assessed in Leishmania infantum and Leishmania braziliensis, the causative agents of visceral and cutaneous leishmaniasis, respectively. This glycoconjugate is highly polymorphic among species with variation in sugars that branch off the conserved Gal(β1,4)Man(α1)-PO4 backbone of repeat units. Here, the immunomodulatory activity of LPGs from Leishmania amazonensis, the causative agent of diffuse cutaneous leishmaniasis, was evaluated in two strains from Brazil. One strain (PH8) was originally isolated from the sand fly and the other (Josefa) was isolated from a human case. The ability of purified LPGs from both strains was investigated during in vitro interaction with peritoneal murine macrophages and CHO cells and in vivo infection with Lutzomyia migonei. In peritoneal murine macrophages, the LPGs from both strains activated TLR4. Both LPGs equally activate MAPKs and the NF-κB inhibitor p-IκBα, but were not able to translocate NF-κB. In vivo experiments with sand flies showed that both stains were able to sustain infection in L. migonei. A preliminary biochemical analysis indicates intraspecies variation in the LPG sugar moieties. However, they did not result in different activation profiles of the innate immune system. Also those polymorphisms did not affect infectivity to the sand fly. 相似文献
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Rafael Silva Menezes Aline Terra Soares Jair Gonzalez Marques Júnior Rafael Garcia Lopes Rafael Fonseca da Arantes Roberto Bianchini Derner Nelson Roberto Antoniosi Filho 《Journal of applied phycology》2016,28(5):2679-2686
The purposes of this study were to assess the influence of culture medium on biomass production, fatty acid, and pigment composition of Choricystis minor var. minor and to evaluate the use of this microalga as a source of fatty raw material for biodiesel production. Cultures of C. minor var. minor were grown using WC (Wright’s cryptophyte) and BBM (Bold’s Basal medium) media. BBM medium produced more biomass (984.3 mg L?1) compared to the WC medium (525.7 mg L?1). Despite this result, WC medium produced a higher methyl ester yield for biodiesel production than the BBM medium (170.0 and 90.2 mg g?1 of biomass, respectively). The average percentage of fatty acids obtained using the WC medium (17.0 %) was similar to soybean (18.0 %) and with similar biomass fatty acid profile. However, for pigment production, carotenoids and chlorophyll concentrations were twice as high when using the BBM medium. 相似文献
88.
Endothelial progenitor cells (EPC) participate in revascularization and angiogenesis. EPC can be cultured in vitro from mononuclear cells of peripheral blood, umbilical cord blood or bone marrow; they also can be transdifferentiated from mesenchymal stem cells (MSC). We isolated EPCs from Wharton's jelly (WJ) using two methods. The first method was by obtaining MSC from WJ and characterizing them by flow cytometry and their adipogenic and osteogenic differentiation, then applying endothelial growth differentiating media. The second method was by direct culture of cells derived from WJ into endothelial differentiating media. EPCs were characterized by morphology, Dil-LDL uptake/UEA-1 immunostaining and testing the expression of endothelial markers by flow cytometry and RT-PCR. We found that MSC derived from WJ differentiated into endothelial-like cells using simple culture conditions with endothelium induction agents in the medium. 相似文献
89.
Gorman Daniel Pucci Marinella Soares Lucy S. H. Turra Alexander Schlacher Thomas A. 《Ecosystems》2019,22(4):796-804
Ecosystems - Land–ocean coupling in the form of riverine inputs of terrestrial matter can constitute an energetic subsidy to food webs in nearshore coastal areas. In regions with distinctly... 相似文献