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排序方式: 共有701条查询结果,搜索用时 15 毫秒
91.
Luciana Albuquerque Fred A. Rainey M. Fernanda Nobre Milton S. da Costa 《Systematic and applied microbiology》2010
Two red-pigmented isolates, with optimum growth temperatures between 45 and 50 °C, were recovered from a hot spring in the Furnas, Área da Fonte 1825 on the Island of São Miguel in the Azores. Phylogenetic analysis of the 16S rRNA gene sequences showed that these organisms represented a new species of the genus Meiothermus. These new isolates could be distinguished from other strains of the species of the genus Meiothermus primarily by the fatty acid composition and polar lipid pattern, since they did not possess 2-OH fatty acids or glycolipid variant GL-1a. Moreover, the two new isolates had the lowest growth temperature range of any of the known species of the genus Meiothermus. On the basis of the results presented here we propose the name Meiothermus granaticius for the new species represented by strains AF-68T (=DSM 23260T = LMG 25524T) and AF-49 (=DSM 23259 = LMG 25525). 相似文献
92.
Babiker MH Gonzalez LF Ryan J Albuquerque F Collins D Elvikis A Frakes DH 《Journal of biomechanics》2012,45(3):440-447
Embolic coiling is the most popular endovascular treatment available for cerebral aneurysms. Nevertheless, the embolic coiling of wide-neck aneurysms is challenging and, in many cases, ineffective. Use of highly porous stents to support coiling of wide-neck aneurysms has become a common procedure in recent years. Several studies have also demonstrated that high porosity stents alone can significantly alter aneurysmal hemodynamics, but differences among different stent configurations have not been fully characterized. As a result, it is usually unclear which stent configuration is optimal for treatment. In this paper, we present a flow study that elucidates the influence of stent configuration on cerebral aneurysm fluid dynamics in an idealized wide-neck basilar tip aneurysm model. Aneurysmal fluid dynamics for three different stent configurations (half-Y, Y and, cross-bar) were first quantified using particle image velocimetry and then compared. Computational fluid dynamics (CFD) simulations were also conducted for selected stent configurations to facilitate validation and provide more detailed characterizations of the fluid dynamics promoted by different stent configurations. In vitro results showed that the Y stent configuration reduced cross-neck flow most significantly, while the cross-bar configuration reduced velocity magnitudes within the aneurysmal sac most significantly. The half-Y configuration led to increased velocity magnitudes within the aneurysmal sac at high parent-vessel flow rates. Experimental results were in strong agreement with CFD simulations. Simulated results indicated that differences in fluid dynamic performance among the different stent configurations can be attributed primarily to protruding struts within the bifurcation region. 相似文献
93.
Bioactivity of crude extracts and some constituents of Blutaparon portulacoides (Amaranthaceae). 总被引:1,自引:0,他引:1
M J Salvador E O Ferreira E M F Pral S C Alfieri S Albuquerque I Y Ito D A Dias 《Phytomedicine》2002,9(6):566-571
Crude extracts (aerial parts and roots, both dried), methylenedioxyflavonol, and a mixture of acyl steryl glycosides isolated from Blutaparon portulacoides, were assayed for their toxicity against Trypanosoma cruzi trypomastigotes and Leishmania amazonensis amastigotes from axenic cultures. The antimicrobial activity was also investigated, in a screening conducted using fifteen strains of Gram-positive and Gram-negative bacteria, along with the yeasts, Candida albicans and Candida tropicalis. To assess the antibacterial activity of the isolated compounds, the minimum inhibitory concentrations (MICs) were determined. There are no reports of acyl steryl glycosides in the genus Blutaparon and their biological activities are being evaluated for the first time. 相似文献
94.
M.W. Biavatti P.C. Vieira M.F.G.F. da Silva J.B. Fernandes S. Albuquerque C.M.I. Magalhes F.C. Pagnocca 《Phytomedicine》2001,8(2):121-124
The hexane extract of the stems of Raulinoa echinata afforded the sesquiterpenes germacrene D (6), 1beta,6alpha-dihydroxy-4-(15)-eudesmene (4) and oplopanone (5); the triterpenes squalene, isomultiflorenol (7), isobauerenol (8) and friedelin (9); the protolimonoids melianone (2) and melianodiol (3); and the pyranocoumarin 3-(1'-1'-dimethylallyl)-lomatin (1), which has not been reported previously as a natural product; together with beta-sitosterol. The hexane extract and some of these compounds were assayed in vitro against trypomastigote forms of Trypanosoma cruzi. Brine shrimp lethality and antimicrobial activities of the crude extract and pure compounds were also evaluated. 相似文献
95.
96.
The presence of muscarinic receptors in sheep and rat pineals was detected by binding of [3H]quinuclidinyl benzilate ([3H]QNB), a potent and specific muscarinic antagonist. [3H]QNB binding to sheep pineal membrane resuspensions was saturable and reversible, with a rate constant for association at 37°C of 6×108M?1min?1 and a rate constant for dissociation of 1×10?2min?1. Kinetic and saturation experiments yielded an equilibrium dissociation constant of 13–18 pM and a concentration of binding sites equivalent to 1.1 pmol/g of original wet weight. This is only about 5% of the level of β-adrenergic receptors. Competition by a variety of cholinergic drugs confirmed the muscarinic nature of the binding sites. Experiments in rats failed to detect a significant decrease in pineal [3H]QNB binding following bilateral superior cervical ganglionectomy, suggesting that the binding sites are not localized exclusively on sympathetic terminals. 相似文献
97.
Leticia Campos André Nascimento Ulysses Albuquerque Elcida Araújo 《Human ecology: an interdisciplinary journal》2016,44(6):775-782
Different criteria are used by human populations around the world in the selection of preferred natural resources. In this study, the following hypotheses were tested: 1) the preference for food native species is related to the number of uses for which the species are cited; 2) the categories of food and medicinal use equally influence the selection of a species as preferred; 3) the preference among native food species is related to its frequency and abundance in the areas of collection. Data collection on species preference was conducted in communities located near the Araripe National Forest (FLONA) in Ceará, Northeastern, Brazil. Both the hypothesis that the preference would relate to the number of uses attributed to species and the hypothesis that food and medicinal categories equally influence the selection of species as preferred ones were corroborated. It was concluded in this study that people optimize both use and collection of native resources using criteria such as the versatility of uses for species and the abundance of the resource in the preferred collection areas. It is believed that this trend may be an adaptive strategy adopted by local communities for the exploitation of native resources. 相似文献
98.
99.
Marcos Vinicius Antunes de Lemos Elisa Peripolli Mariana Piatto Berton Fabiele Loise Braga Feitosa Bianca Ferreira Olivieri Nedenia Bonvino Stafuzza Rafael Lara Tonussi Sabrina Kluska Hermenegildo Lucas Justino Chiaia Lenise Mueller Adrielli Mathias Ferrinho Angelica Simone Cravo Prereira Henrique Nunes de Oliveira Lucia Galvão de Albuquerque Fernando Baldi 《Journal of applied genetics》2018,59(2):203-223
The aim of this study was to analyze the association between the copy number variation regions (CNVRs) and fatty acid profile phenotypes for saturated (SFA), monosaturated (MUFA), polyunsaturated (PUFA), ω6 and ω3 fatty acids, PUFA/SFA and ω6/ω3 ratios, as well as for their sums, in Nellore cattle (Bos primigenius indicus). A total of 963 males were finished in feedlot and slaughtered with approximately 2 years of age. Animals were genotyped with the BovineHD BeadChip (Illumina Inc., San Diego, CA, USA). The copy number variation (CNV) detection was performed using the PennCNV algorithm. Log R ratio (LRR) and allele B frequency (BAF) were used to estimate the CNVs. The association analyses were done using the CNVRuler software and applying a logistic regression model. The phenotype was adjusted using a linear model considering the fixed effects of contemporary group and the animal age at slaughter. The fatty acid profile was analyzed on samples of longissimus thoracis muscle using gas chromatography with a 100-m capillary column. For the association analysis, the adjusted phenotypic values were considered for the traits, while the data was adjusted for the effects of the farm and year of birth, management groups at birth, weaning, and superannuation. A total of 186 CNVRs were significant for SFA (43), MUFA (42), PUFA (66), and omega fatty acid (35) groups, totaling 278 known genes. On the basis of the results, several genes were associated with several fatty acids of different saturations. Olfactory receptor genes were associated with C12:0, C14:0, and C18:0 fatty acids. The SAMD8 and BSCL2 genes, both related to lipid metabolic process, were associated with C12:0. The RAPGEF6 gene was found to be associated with C18:2 cis-9 cis-12 n-6, and its function is related to regulation of GTPase activity. Among the results, we highlighted the olfactory receptor activity (GO:0004984), G-protein-coupled receptor activity (GO:0004930), potassium:proton antiporter activity (GO:0015386), sodium:proton antiporter activity (GO:0015385), and odorant-binding (GO:0005549) molecular functions. A large number of genes associated with fatty acid profile within the CNVRs were identified in this study. These findings must contribute to better elucidate the genetic mechanism underlying the fatty acid profile of intramuscular fat in Nellore cattle. 相似文献
100.
Souza AP Albuquerque C Torronteguy C Frasson A Maito F Pereira L Duval da Silva V Zerwes F Raynes D Guerriero V Bonorino C 《Cell stress & chaperones》2009,14(3):301-310
HspBP1 is a co-chaperone that binds to and regulates the chaperone Hsp70 (Hsp70 is used to refer to HSPA1A and HSPA1B). Hsp70
is known to be elevated in breast tumor tissue, therefore the purpose of these studies was to quantify the expression of HspBP1
in primary breast tumors and in serum of these patients with a follow-up analysis after 6 to 7 years. Levels of HspBP1, Hsp70,
and anti-HspBP1 antibodies in sera of breast cancer patients and healthy individuals were measured by enzyme-linked immunosorbent
assay. Expression of HspBP1 was quantified from biopsies of tumor and normal breast tissue by Western blot analysis. The data
obtained were analyzed for association with tumor aggressiveness markers and with patient outcome. The levels of HspBP1 and
Hsp70 were significantly higher in sera of patients compared to sera of healthy individuals. HspBP1 antibodies did not differ
significantly between groups. HspBP1 levels were significantly higher in tumor (14.46 ng/μg protein, n = 51) compared to normal adjacent tissue (3.17 ng/μg protein, n = 41, p < 0.001). Expression of HspBP1 was significantly lower in patients with lymph node metastasis and positive for estrogen receptors.
HspBP1 levels were also significantly lower in patients with a higher incidence of metastasis and death following a 6 to 7-year
follow-up. The HspBP1/Hsp70 molar ratio was not associated with the prognostic markers analyzed. Our results indicate that
low HspBP1 expression could be a candidate tumor aggressiveness marker.
This work was supported by FAPERGS, CNPq, and the National Institute of General Medical Sciences grant number GM072628-02
(V.G.)
The expression of HspBP1 (an Hsp70 co-chaperone) was analyzed in tumor samples and sera from breast cancer patients. HspBP1
is over expressed in these tumors and a seven year follow-up analysis found an association with a poor prognosis. Chaperones
have been shown to play important roles in tumor biology and immunology; therefore, we believe the data in this study will
serve as a basis for the formulation of a new hypothesis on chaperone-co-chaperone interactions and their role in tumor growth. 相似文献