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101.
Luiz Henrique Agra Cavalcante-Silva Ana Carolina de Carvalho Correia José Maria Barbosa-Filho Bagnólia Araújo da Silva Bárbara Viviana de Oliveira Santos Daysianne Pereira de Lira Jéssica Celestino Ferreira Sousa George Emmanuel C. de Miranda Fabiana de Andrade Cavalcante Magna Suzana Alexandre-Moreira 《Marine drugs》2013,11(5):1553-1564
In this work, we investigated the spasmolytic effect of caulerpine, a bisindole alkaloid isolated from marine algae of the Caulerpa genus, on guinea pig ileum. Our findings indicated that caulerpine inhibited phasic contractions induced by carbachol (IC50 = 7.0 ± 1.9 × 10−5 M), histamine (IC50 = 1.3 ± 0.3 × 10−4 M) and serotonin (IC50 = 8.0 ± 1.4 × 10−5 M) in a non-selective manner. Furthermore, caulerpine concentration-dependently inhibited serotonin-induced cumulative contractions (pD′2 = 4.48 ± 0.08), shifting the curves to the right with Emax reduction and slope of 2.44 ± 0.21, suggesting a noncompetitive antagonism pseudo-irreversible. The alkaloid also relaxed the ileum pre-contracted by KCl (EC50 = 9.0 ± 0.9 × 10−5 M) and carbachol (EC50 = 4.6 ± 0.7 × 10−5 M) in a concentration-dependent manner. This effect was probably due to inhibition of Ca2+ influx through voltage-gated calcium channels (CaV), since caulerpine slightly inhibited the CaCl2-induced contractions in depolarizing medium without Ca2+, shifting the curves to the right and with Emax reduction. According to these results, the spasmolytic effect of caulerpine on guinea pig ileum seems to involve inhibition of Ca2+ influx through CaV. However, other mechanisms are not discarded. 相似文献
102.
Tatiana da Rosa Guimar?es Carlos Guillermo Quiroz Caroline Rigotto Simone Quintana de Oliveira Maria Tereza Rojo de Almeida éverson Miguel Bianco Maria Izabel Goulart Moritz Jo?o Luís Carraro Jorge Alejandro Palermo Gabriela Cabrera Eloir Paulo Schenkel Flávio Henrique Reginatto Cláudia Maria Oliveira Sim?es 《Marine drugs》2013,11(11):4176-4192
The n-butanol fraction (BF) obtained from the crude extract of the marine sponge Petromica citrina, the halistanol-enriched fraction (TSH fraction), and the isolated compounds halistanol sulfate (1) and halistanol sulfate C (2), were evaluated for their inhibitory effects on the replication of the Herpes Simplex Virus type 1 (HSV-1, KOS strain) by the viral plaque number reduction assay. The TSH fraction was the most effective against HSV-1 replication (SI = 15.33), whereas compounds 1 (SI = 2.46) and 2 (SI = 1.95) were less active. The most active fraction and these compounds were also assayed to determine the viral multiplication step(s) upon which they act as well as their potential synergistic effects. The anti-HSV-1 activity detected was mediated by the inhibition of virus attachment and by the penetration into Vero cells, the virucidal effect on virus particles, and by the impairment in levels of ICP27 and gD proteins of HSV-1. In summary, these results suggest that the anti-HSV-1 activity of TSH fraction detected is possibly related to the synergic effects of compounds 1 and 2. 相似文献
103.
104.
José L. Chávez Francis J. Pierce Todd V. Elliott Robert G. Evans Yunseop Kim William M. Iversen 《Precision Agriculture》2010,11(1):11-26
Precision irrigation systems can have inherent errors that affect the accuracy of variable water application rates controllers,
as well as affect the controllers’ performance when evaluated on different continuous move irrigation systems configurations.
The objective of this study was to assess the performance of a remote irrigation monitoring and control system (RIMCS) installed
on two separate linear move (LM) irrigation systems. The RIMCS varies water application rates by pulsing nozzles controlled
by solenoids connected via relays to a single board computer (SBC) with wireless Ethernet connection to a remote server. The
system also monitors irrigation system flow, pressure, position and wireless field sensor networks. The system was installed
on a LM irrigation system in Prosser, Washington, USA and on a LM in the Nesson Valley of North Dakota, USA. For the LM at
Prosser, four pre-defined irrigation patterns were imposed and variable rates were applied as a percentage of the nozzle base
application rate. Each nozzle was pulsed across the span length and along the LM travel direction. For the LM at the Nesson
Valley, a quadratic pattern was imposed pulsing banks of nozzles along the LM travel direction. Standard catch can tests were
performed and the system performance was evaluated by comparing measured catch can water depths with pre-determined target
values. The RIMCS accuracy was found to be in the range of the LM uniform water depth application uniformity coefficients
of 88–96%. The RIMCS was successfully transferred to another LM in North Dakota as indicated by the relatively low variable
rate application errors of –8.8 ± 8.1% and −0.14 ± 6.7% for the two spans. 相似文献
105.
Lima MD Fang S Lepró X Lewis C Ovalle-Robles R Carretero-González J Castillo-Martínez E Kozlov ME Oh J Rawat N Haines CS Haque MH Aare V Stoughton S Zakhidov AA Baughman RH 《Science (New York, N.Y.)》2011,331(6013):51-55
Multifunctional applications of textiles have been limited by the inability to spin important materials into yarns. Generically applicable methods are demonstrated for producing weavable yarns comprising up to 95 weight percent of otherwise unspinnable particulate or nanofiber powders that remain highly functional. Scrolled 50-nanometer-thick carbon nanotube sheets confine these powders in the galleries of irregular scroll sacks whose observed complex structures are related to twist-dependent extension of Archimedean spirals, Fermat spirals, or spiral pairs into scrolls. The strength and electronic connectivity of a small weight fraction of scrolled carbon nanotube sheet enables yarn weaving, sewing, knotting, braiding, and charge collection. This technology is used to make yarns of superconductors, lithium-ion battery materials, graphene ribbons, catalytic nanofibers for fuel cells, and titanium dioxide for photocatalysis. 相似文献
106.
Matías Santini Elsa Lucila Camadro Olga Noemí Marcellán Luis Ernesto Erazzú 《American Journal of Potato Research》2000,77(4):211-218
Five diploid hybrid families derived from crosses between haploids of three Argentinian cultivars and three diploid wild species,Solanum gourlayi, S. chacoense andS. spegazzinii, were evaluated in a field experiment in Balcarce. All plants were androsterile and, thus, could not be screened for 2n pollen production. Data on agronomic tuber traits were statistically analyzed. Differences among families were non-significant for tuber number/plant, but were significant for tuber weight/plant and dry matter content (with values above 21.0% in two of them). The relative frequencies of tubers in the categories established for size, skin texture, and eye depth were family dependent, but they were familiy independent in the categories established for tuber shape and skin color. Great morphological variability was detected for all the traits studied, and plants with high yield and high dry matter content were identified. These families can be used as sources of germplasm in breeding and to explore heterotic responses in 2x × 4x crosses, given the capacity of some plants to produce 2n eggs, as found in a related investigation. 相似文献
107.
Aparicio-Fernández X Reynoso-Camacho R Castaño-Tostado E García-Gasca T González de Mejía E Guzmán-Maldonado SH Elizondo G Yousef GG Lila MA Loarca-Pina G 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(1):35-40
Jamapa bean is a black Phaseolus vulgaris variety rich in condensed tannins, anthocyanins and flavonols with interesting biological activities. The objective of this
work was to evaluate the antiradical capacity (ARC) of a Jamapa bean methanolic extract (BME) and some of the proanthocyanidin-rich
fractions derived from it, using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The effect of the BME on some proteins involved
in apoptosis on HeLa cells was also evaluated. A strong correlation between proanthocyanidin concentration in BME and antiradical
capacity was found, suggesting that these compounds contribute significantly to antiradical activity. BME was a better radical
scavenger than butylated hydroxytoluene (45.6 and 33.9% ARC at 400 μM, respectively). Two proanthocyanidin-rich fractions
obtained after a preliminary separation of the BME using Toyopearl (TP4 and TP6) exhibited a higher antiradical activity than
the parent extract. The treatment of HeLa cells with 35 μg BME/ml/24 h increased the expression of Bax and Caspase-3, pro-apoptotic
proteins (6.13 and 1.2 times for Caspase-3 and Bax, respectively). The mechanism of action of some proteins involved in apoptosis
was also evaluated, and the results suggest that black Jamapa bean could be an important source of polyphenolic compounds
with potential biological use as antioxidant and anticancer agents. 相似文献
108.
Genetic parameters for spawning and growth traits in the Pacific white shrimp (Penaeus (Litopenaeus) vannamei) 下载免费PDF全文
Alejandra Caballero‐Zamora Eugenia Guadalupe Cienfuegos‐Rivas Hugo H Montaldo Gabriel Ricardo Campos‐Montes Alfonso Martínez‐Ortega Héctor Castillo‐Juárez 《Aquaculture Research》2015,46(4):833-839
The aim of this study was to estimate genetic parameters for spawning traits and growth traits in a breeding line of Pacific white shrimp, Penaeus (Litopenaeus) vannamei, selected for growth and survival. Traits studied were number of eggs (NE) and number of nauplii (NN) and female body weight at insemination (FWI) and body weight at 130 days of age (BW130). Genetic parameters were estimated using a multivariate animal model. Heritability for NE and NN were estimated as 0.13 ± 0.04 and 0.03 ± 0.04 respectively. The contribution to NN total variation due to ‘factors associated with male’ effect was estimated as 0.47 ± 0.07. In the cases of FWI and BW130, heritability was estimated as 0.44 ± 0.08 and 0.19 ± 0.03 respectively. Genetic correlation between FWI and NE was estimated as 0.49 ± 0.15, between FWI and NN as 0.54 ± 0.39 and between NE and NN as 0.27 ± 0.41, whereas the genetic correlations of FWI, NE and NN with BW130 were 0.30 ± 0.13, ?0.21 ± 0.19 and ?0.25 ± 0.38 respectively. Although it is important to perform more studies on this issue, our results found no evidence of a genetic antagonistic effect between female reproductive traits and body weight at harvesting (130 days of age) in P. vannamei. 相似文献
109.
110.