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941.
942.
Flavio Tocci Moreira Silvia Cristina Ramos Andrea Moreira Monteiro Tatiana Helfenstein Magnus Gidlund Nagila Raquel Teixeira Damasceno Antonio Martins Figueiredo Neto Maria Cristina Izar Francisco Antonio Helfenstein Fonseca 《Life sciences》2014
Aims
To compare the effects of two of the most effective lipid-lowering therapies with similar LDL-cholesterol reduction capacity on the innate and adaptive immune responses through the evaluation of autoantibodies anti-oxidized LDL (anti-oxLDL Abs) and electronegative LDL [LDL(−)] levels.Main methods
We performed a prospective, randomized, open label study, with parallel arms and blinded endpoints. One hundred and twelve subjects completed the study protocol and received rosuvastatin 40 mg or ezetimibe/simvastatin 10/40 mg for 12 weeks. Lipids, apolipoproteins, LDL(−), and anti-oxLDL Abs (IgG) were assayed at baseline and end of study.Key findings
Main clinical and laboratory characteristics were comparable at baseline. Lipid modifications were similar in both treatment arms, however, a significant raise in anti-oxLDL Abs levels was observed in subjects treated with rosuvastatin (p = 0.026 vs. baseline), but not in those receiving simvastatin/ezetimibe. (p = 0.233 vs. baseline), thus suggesting modulation of adaptive immunity by a potent statin. Titers of LDL(−) were not modified by the treatments.Significance
Considering atherosclerosis as an immune disease, this study adds new information, showing that under similar LDL-cholesterol reduction, the choice of lipid-lowering therapy can differently modulate adaptive immune responses. 相似文献943.
Claudia Mendon?a Bezerra Luciano Pamplona de Góes Cavalcanti Rita de Cássia Moreira de Souza Silvia Ermelinda Barbosa Samanta Cristina das Chagas Xavier Ana Maria Jansen Relrison Dias Ramalho Liléia Diotaiut 《Memórias do Instituto Oswaldo Cruz》2014,109(7):887-898
The role played by different mammal species in the maintenance of Trypanosoma
cruzi is not constant and varies in time and place. This study aimed to
characterise the importance of domestic, wild and peridomestic hosts in the
transmission of T. cruzi in Tauá, state of Ceará, Caatinga area,
Brazil, with an emphasis on those environments colonised by Triatoma
brasiliensis. Direct parasitological examinations were performed on
insects and mammals, serologic tests were performed on household and outdoor mammals
and multiplex polymerase chain reaction was used on wild mammals. Cytochrome b was
used as a food source for wild insects. The serum prevalence in dogs was 38% (20/53),
while in pigs it was 6% (2/34). The percentages of the most abundantly infected wild
animals were as follows: Thrichomys laurentius 74% (83/112)
and Kerodon rupestris 10% (11/112). Of the 749 triatomines
collected in the household research, 49.3% (369/749) were positive for T.
brasiliensis, while 6.8% were infected with T. cruzi
(25/369). In captured animals, T. brasiliensis shares a
natural environment with T. laurentius, K.
rupestris, Didelphis albiventris, Monodelphis
domestica, Galea spixii, Wiedomys
pyrrhorhinos, Conepatus semistriatus and Mus
musculus. In animals identified via their food
source, T. brasiliensis shares a natural environment with
G. spixii, K. rupestris, Capra hircus, Gallus
gallus, Tropidurus oreadicus and Tupinambis merianae.
The high prevalence of T. cruzi in household and peridomiciliar
animals reinforces the narrow relationship between the enzootic cycle and humans in
environments with T. brasiliensis and characterises it as
ubiquitous. 相似文献
944.
Leonardo José de Moura Carvalho Aline da Silva Moreira Cláudio Tadeu Daniel-Ribeiro Yuri Chaves Martins 《Memórias do Instituto Oswaldo Cruz》2014,109(5):577-588
Cerebral malaria (CM) is a life-threatening complication of Plasmodium
falciparum malaria that continues to be a major global health problem.
Brain vascular dysfunction is a main factor underlying the pathogenesis of CM and can
be a target for the development of adjuvant therapies for the disease. Vascular
occlusion by parasitised red blood cells and vasoconstriction/vascular dysfunction
results in impaired cerebral blood flow, ischaemia, hypoxia, acidosis and death. In
this review, we discuss the mechanisms of vascular dysfunction in CM and the roles of
low nitric oxide bioavailability, high levels of endothelin-1 and dysfunction of the
angiopoietin-Tie2 axis. We also discuss the usefulness and relevance of the murine
experimental model of CM by Plasmodium berghei ANKA to identify
mechanisms of disease and to screen potential therapeutic interventions. 相似文献
945.
Annaliese S. Mason Matthew N. Nelson Junko Takahira Wallace A. Cowling Gustavo Moreira Alves Arkaprava Chaudhuri Ning Chen Mohana E. Ragu Jessica Dalton-Morgan Olivier Coriton Virginie Huteau Frédérique Eber Anne-Marie Chèvre Jacqueline Batley 《Genetics》2014,197(1):273-283
Production of allohexaploid Brassica (2n = AABBCC) is a promising goal for plant breeders due to the potential for hybrid heterosis and useful allelic contributions from all three of the Brassica genomes present in the cultivated diploid (2n = AA, 2n = BB, 2n = CC) and allotetraploid (2n = AABB, 2n = AACC, and 2n = BBCC) crop species (canola, cabbages, mustards). We used high-throughput SNP molecular marker assays, flow cytometry, and fluorescent in situ hybridization (FISH) to characterize a population of putative allohexaploids derived from self-pollination of a hybrid from the novel cross (B. napus × B. carinata) × B. juncea to investigate whether fertile, stable allohexaploid Brassica can be produced. Allelic segregation in the A and C genomes generally followed Mendelian expectations for an F2 population, with minimal nonhomologous chromosome pairing. However, we detected no strong selection for complete 2n = AABBCC chromosome complements, with weak correlations between DNA content and fertility (r2 = 0.11) and no correlation between missing chromosomes or chromosome segments and fertility. Investigation of next-generation progeny resulting from one highly fertile F2 plant using FISH revealed general maintenance of high chromosome numbers but severe distortions in karyotype, as evidenced by recombinant chromosomes and putative loss/duplication of A- and C-genome chromosome pairs. Our results show promise for the development of meiotically stable allohexaploid lines, but highlight the necessity of selection for 2n = AABBCC karyotypes. 相似文献
946.
Mariana Moreira Claudino Thaisa Francielle Souza Domingos Geisiane Alves da Silva Rainiomar Raimundo Fonseca Diana Negrão Cavalcanti Eladio Flores Sanchez Valéria Laneuville Teixeira André Lopes Fuly 《Journal of applied phycology》2014,26(5):2047-2054
The ability of extracts and fractions of the red seaweed Plocamium brasiliense to inhibit hemorrhagic, edematogenic, hemolytic, clotting and proteolytic activities of Lachesis muta snake venom was analyzed. In Brazil, snakebites by L. muta are low (2 %) when compared to Bothrops genus (90 %); however, their lethality indexes are three times higher than Bothrops. Envenomation by L. muta venom results in hemorrhage, pain, necrosis, hemolysis, myotoxicity, and death. Since antivenom does not efficiently neutralize local effects, a large number of researchers have attempted to identify molecule(s) from natural sources to inhibit such activities to use them as an alternative treatment for snakebite. We tested four extracts of seaweed P. brasiliense obtained with solvents of increasing polarities: n-hexane (HEX), dichloromethane (DCM), ethyl acetate (ACE), and hydroalcohol (HYD). Extracts of alga or fractions were incubated with L. muta venom, and then, biological assays were performed. The extracts, except the HYD, inhibited all the assays but with different potencies. The DCM extract fully inhibited all activities. Moreover, DCM and HEX extracts inhibited hemolysis induced by a phospholipase A2 isolated from L. muta venom (LM-PLA2-I). A fraction from HEX enriched in cholesterol isolated from HEX extract inhibited proteolysis by L. muta venom and hemolysis by LM-PLA2-I; in contrast, monoterpenes isolated from DCM extract did not inhibit both activities. Seaweeds may be a promising source of natural inhibitors of the toxic effects caused by snakebite by L. muta venom, and they may be used to develop new strategies for antivenom treatment. 相似文献
947.
Maria Fernanda Antunes Cruz Fabrício Ávila Rodrigues Ana Paula Cardoso Diniz Maurilio Alves Moreira Everaldo Gonçalves Barros 《Journal of Phytopathology》2014,162(2):133-136
Asian soybean rust (ASR), caused by Phakopsora pachyrhizi, is one of the most important diseases on soybean. At the moment, ASR is managed mainly with fungicides due to the absence of commercial cultivars with resistance to this disease. This study evaluated the effects of acibenzolar‐Smethyl (ASM), jasmonic acid (JA), potassium silicate (PS) and calcium silicate (CS) on soybean resistance to ASR. The ASM, JA and PS were sprayed to leaves 24 h prior to inoculation with P. pachyrhizi. The CS was amended to the soil. The incubation period (time from the inoculation until symptoms development) was longer for plants growing in soil amended with CS or sprayed with ASM in comparison with plants sprayed with water (control). Plants sprayed with ASM had longer latent period (time from the inoculation until signs appearance) in comparison with the control plants. Plants sprayed with PS showed fewer uredia per cm² of leaf in relation to the control plants. The ASM and PS were the most effective treatments in reducing the ASR symptoms in contrast to the JA and CS treatments. The JA served as an inducer of susceptibility to ASR. 相似文献
948.
Background
The details of the functional interaction between G proteins and the G protein coupled receptors (GPCRs) have long been subjected to extensive investigations with structural and functional assays and a large number of computational studies.Scope of review
The nature and sites of interaction in the G-protein/GPCR complexes, and the specificities of these interactions selecting coupling partners among the large number of families of GPCRs and G protein forms, are still poorly defined.Major conclusions
Many of the contact sites between the two proteins in specific complexes have been identified, but the three dimensional molecular architecture of a receptor-Gα interface is only known for one pair. Consequently, many fundamental questions regarding this macromolecular assembly and its mechanism remain unanswered.General significance
In the context of current structural data we review the structural details of the interfaces and recognition sites in complexes of sub-family A GPCRs with cognate G-proteins, with special emphasis on the consequences of activation on GPCR structure, the prevalence of preassembled GPCR/G-protein complexes, the key structural determinants for selective coupling and the possible involvement of GPCR oligomerization in this process. 相似文献949.
950.
Ana Paula B. Moreira Gwen Duytschaever Luciane A. Chimetto Tonon Graciela M. Dias Milene Mesquita Margo Cnockaert Ronaldo B. Francini-Filho Paul De Vos Cristiane C. Thompson Fabiano L. Thompson 《Current microbiology》2014,69(4):405-411
Three novel isolates (A-354T, A-328, and A-384) were retrieved from apparently healthy scleractinian Madracis decactis in the remote St Peter & St Paul Archipelago, Mid-Atlantic Ridge, Brazil. The novel isolates formed a distinct lineage based on the phylogenetic reconstruction using the 16S rRNA and pyrH gene sequences. They fell into the Mediterranei clade and their closest phylogenetic neighbour was V. mediterranei species, sharing upto 98.1 % 16S rRNA gene sequence similarity. Genomic analysis including in silico DDH, MLSA, AAI and genomic signature distinguished A-354T from V. mediterranei LMG 19703 (=AK1) with values of 33.3, 94.2, 92 %, and 11.3, respectively. Phenotypically, the novel isolates can be differentiated from V. mediterranei based on the four following features. They do not grow at 8 % NaCl; use d-gluconic acid but not l-galactonic acid lactone as carbon source; and do not have the fatty acid C18:0. Differentiation from both the other Mediterranei clade species (V. maritimus and V. variabilis) is supported by fifteen features. The novel species show lysine decarboxylase and tryptophan deaminase, but not gelatinase and arginine dihydrolase activity; produce acetoin; use α-d-lactose, N-acetyl-d-galactosamine, myo-Inositol, d-gluconic acid, and β-hydroxy-d,l-butyric acid; and present the fatty acids C14:0 iso, C15:0 anteiso, C16:0 iso, C17:0 anteiso, and C17:1x8c . Whole-cell protein profiles, based on MALDI-TOF, showed that the isolates are not clonal and also distinguished them from the closes phylogenetic neighbors. The name Vibrio madracius sp. nov. is proposed to encompass these novel isolates. The G+C content of the type strain A-354T (=LMG 28124T=CBAS 482T) is 44.5 mol%. 相似文献