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51.
Leite AC de Lima RS Moreira DR Cardoso MV Gouveia de Brito AC Farias Dos Santos LM Hernandes MZ Kiperstok AC de Lima RS Soares MB 《Bioorganic & medicinal chemistry》2006,14(11):3749-3757
A novel series of thiosemicarbazone and aminoacyl-thiazolidones derivatives were synthesized. Their structure suggests that these compounds could have anti-Trypanosoma cruzi activity. Biological evaluation indicates that some of these compounds are able to inhibit the growth of T. cruzi in concentrations non-cytotoxic to mammalian cells. Docking studies were carried out in order to investigate the binding pattern of these compounds for the T. cruzi cruzain (TCC) protein, and these showed a significant correlation with experimental data. 相似文献
52.
de Moura e Dias Mariana dos Reis Louzano Sandra Aparecida da Conceição Lisiane Lopes da Conceição Fernandes Rayssa de Oliveira Mendes Tiago Antônio Pereira Solange Silveira de Oliveira Leandro Licursi Gouveia Peluzio Maria do Carmo 《Probiotics and antimicrobial proteins》2021,13(6):1621-1631
Probiotics and Antimicrobial Proteins - The development of adjuvant therapies for obesity treatment is justified by the high prevalence of this disease worldwide, and the relationship between... 相似文献
53.
Gouveia AM Guimarães CP Oliveira ME Sá-Miranda C Azevedo JE 《The Journal of biological chemistry》2003,278(7):4389-4392
It is now generally accepted that Pex5p, the receptor for most peroxisomal matrix proteins, cycles between the cytosol and the peroxisomal compartment. According to current models of peroxisomal biogenesis, this intracellular trafficking of Pex5p is coupled to the transport of newly synthesized peroxisomal proteins into the organelle matrix. However, direct evidence supporting this hypothesis was never provided. Here, using an in vitro peroxisomal import system, we show that insertion of Pex5p into the peroxisomal membrane requires the presence of cargo proteins. Strikingly the peroxisomal docking/translocation machinery is also able to catalyze the membrane insertion of a Pex5p truncated molecule lacking any known cargo-binding domain. These results suggest that the cytosol/peroxisomal cycle in which Pex5p is involved is directly or indirectly regulated by Pex5p itself and not by the peroxisomal docking/translocation machinery. 相似文献
54.
The objective of this study was to evaluate the effects of equine chorionic gonadotropin (eCG) treatment on the number of induced accessory corpora lutea (CL), plasma progesterone concentrations and pregnancy rate in cross-bred heifers after transfer of frozen-thawed (1.5M ethylene glycol) embryos. All recipients received 500 microg PGF2alpha (dl-cloprostenol, i.m.) at random stages of the estrous cycle (Day 0) and were observed for estrus for 7 days. On Day 14, heifers detected in estrus between 2 and 7 days after PGF2alpha treatment were randomly allocated to four groups ( n=83 per group) and given 0 (control), 200, 400, or 600 IU of eCG. Two days later (Day 16), these recipients were given PGF2alpha and observed for estrus. Six to eight days after detection of estrus, plasma samples were collected to determine progesterone concentration and ultrasonography was performed to observe ovarian structures. Heifers with multiple CL or a single CL >15 mm in diameter received an embryo by direct transfer. Embryos of excellent and good quality were thawed and transferred to the recipients by the same veterinarian. Pregnancy was diagnosed by ultrasonography and confirmed by transrectal palpation 21 and 83 days after embryo transfer (ET), respectively. Plasma progesterone concentrations on the day of transfer (Day 7 of the estrous cycle) were 3.9+/-0.7, 4.2+/-0.4,6.0+/-0.4 and 7.8+/-0.6 ng/ml for groups Control, 200, 400, and 600, respectively (Control versus treated groups P=0.009; 200 versus 400 and 600 groups P=0.0001; and 400 versus 600 P=0.012 ). Conception rates 83 days after ET were 41.9, 50.0, 25.0, and 20.9% for groups Control, 200, 400, and 600, respectively (200 versus 400 and 600 groups P=0.0036 ). In conclusion, an increase in progesterone concentration, induced by eCG treatment, did not improve pregnancy rates in ET recipients. Conversely, there was a decline in conception rates in the animals with the highest plasma progesterone concentrations. 相似文献
55.
Acceptor specificity of the human leukocyte alpha3 fucosyltransferase: role of FucT-VII in the generation of selectin ligands 总被引:2,自引:2,他引:0
Britten CJ; van den Eijnden DH; McDowell W; Kelly VA; Witham SJ; Edbrooke MR; Bird MI; de Vries T; Smithers N 《Glycobiology》1998,8(4):321-327
The alpha3 fucosyltransferase, FucT-VII, is one of the key
glycosyltransferases involved in the biosynthesis of the sialyl Lewis X
(sLex) antigen on human leukocytes. The sialyl Lewis X antigen
(NeuAcalpha(2-3)Galbeta(1-4)[Fucalpha(1-3)]GlcNAc-R) is an essential
component of the recruitment of leukocytes to sites of inflammation,
mediating the primary interaction between circulating leukocytes and
activated endothelium. In order to characterize the enzymatic properties of
the leukocyte alpha3 fucosyltransferase FucT-VII, the enzyme has been
expressed in Trichoplusia ni insect cells. The enzyme is capable of
synthesizing both sLexand sialyl-dimeric-Lexstructures in vitro , from
3'-sialyl-lacNAc and VIM-2 structures, respectively, with only low levels
of fucose transfer observed to neutral or 3'-sulfated acceptors. Studies
using fucosylated NeuAcalpha(2-3)-(Galbeta(1- 4)GlcNAc)3-Me acceptors
demonstrate that FucT-VII is able to synthesize both di-fucosylated and
tri-fucosylated structures from mono- fucosylated precursors, but
preferentially fucosylates the distal GlcNAc within a polylactosamine
chain. Furthermore, the rate of fucosylation of the internal GlcNAc
residues is reduced once fucose has been added to the distal GlcNAc. These
results indicate that FucT-VII is capable of generating complex selectin
ligands, in vitro , however the order of fucose addition to the lactosamine
chain affects the rate of selectin ligand synthesis.
相似文献
56.
57.
L. Campenni’ B. P. Nobre C. A. Santos A. C. Oliveira M. R. Aires-Barros A. M. F. Palavra L. Gouveia 《Applied microbiology and biotechnology》2013,97(3):1383-1393
Today microalgae represent a viable alternative source for high-value products. The specie Chlorella protothecoides (Cp), heterotrophically grown, has been widely studied and provides a high amount of lutein and fatty acids (FA) and has a good profile for biodiesel production. This work studies carotenoid and FA production by autotrophic grown Cp. Cp was grown until the medium’s nitrogen was depleted, then diluted in NaCl solution, resulting in nutritional, luminosity, and salinity stresses. Different NaCl concentrations were tested (10, 20, 30 g/L) at two different dilutions. After dilution, a color shifting from green to orange-red was noticed, showing carotenoid production. The best production of both carotenoids and FA was attained with a 20 g/L NaCl solution. The total carotenoid content was 0.8 % w/w (canthaxanthin (23.3 %), echinenone (14.7 %), free astaxanthin (7.1 %), and lutein/zeaxanthin (4.1 %)). Furthermore, the total lipid content reached 43.4 % w/w, with a FA composition of C18:1 (33.64 %), C16:0 (23.30 %), C18:2 (11.53 %), and less than 12 % of C18:3, which is needed to fulfill the biodiesel quality specifications (EN 14214). 相似文献
58.
59.
Long-term pattern of population dynamics in the field vole from central Europe: cyclic pattern with amplitude dampening 总被引:1,自引:0,他引:1
Ana Gouveia Vladimír Bejček Jiří Flousek František Sedláček Karel Šťastný Jan Zima Nigel G. Yoccoz Nils Chr. Stenseth Emil Tkadlec 《Population Ecology》2015,57(4):581-589
The subject of population cycles is regarded as controversial due to a number of unsettled questions such as whether or not cyclic patterns are governed by the same processes at high and low latitudes in Europe. Recent evidence suggests that the dynamics at high and low latitudes share the common temporal pattern of vole dynamics referred to as collapsing population cycles. Despite concurrent interest, the key contention around the causal mechanisms that drive population cycles remains a hot topic in ecology. The aims of this study are to supplement information on the seasonal population dynamics of the field vole Microtus agrestis in the Czech Republic by analysing 25 years of time series data. By applying robust estimation procedures, we estimated several parameters to describe population dynamics, such as population variability, amplitude dampening, cycle period, order of the dynamics and the structure of density dependence. The parameters indicate that field vole dynamics in central Europe are highly variable, cyclic dynamics of order two, with peaks in abundance occurring regularly at intervals of 4–5 years. In addition to exhibiting population cycles, the field vole populations show a pattern of dampened amplitude as observed elsewhere in Europe, including northern latitudes. By analysing temporal trends in seasonal abundances, population growth rates and environmental temperatures, we did not obtain evidence to support the hypothesis that amplitude dampening results from the negative effect of increasingly mild winters on winter population growth rates. 相似文献
60.
Filippe Elias de Freitas Soares José Humberto de Queiroz Jackson Victor de Araújo Paula Viana Queiroz Angélica de Souza Gouveia Emy Hiura 《Biocontrol Science and Technology》2015,25(3):337-344
Nematophagous fungi produce chitinases that may be important in the process of infection of eggs and larvae of nematodes. This study aimed to produce, purify, characterise and test the nematicidal action of extracellular chitinases produced by Monacrosporium thaumasium on Panagrellus redivivus. Mycelia from M. thaumasium were used to inoculate a solid medium for chitinase production. The enzymes were purified using a specific technique of adsorption for chitinases. The chitinase activity was determined at different pHs and temperatures. NF34 produced two distinct chitinases (27 and 30 kDa). After 72 hours, these enzymes provided a significant reduction (80%; p < 0.01) of the number of P. redivivus larvae, compared to control. It was shown that isolate NF34 produced chitinases with nematicidal activity. Thus, other experimental designs on geohelminths or even arthropods that transmit diseases may become a new aspect of the field of study of biological control using predatory nematophagous fungi. 相似文献