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61.
Iserhard CA Kaminski LA Marchiori MO Teixeira EC Romanowski HP 《Neotropical Entomology》2007,36(4):612-615
Lepidopterism by Hylesia nigricans (Berg) moth is recorded for the first time in southern Brazil. Preventive strategies of control are proposed based on information on the biology and ecology of this moth. 相似文献
62.
Jaquelline Carla Valamiel de Oliveira-Silva Girley Francisco Machado-de-Assis Maykon Tavares Oliveira Nívia Carolina Noguieira Paiva Márcio Sobreira Silva Araújo Cláudia Martins Carneiro Olindo Assis Martins-Filho Helen Rodrigues Martins Marta de Lana 《Memórias do Instituto Oswaldo Cruz》2015,110(1):86-94
Trypanosoma cruzi strains from distinct geographic areas show differences in drug
resistance and association between parasites genetic and treatment response has been
observed. Considering that benznidazole (BZ) can reduce the parasite burden and
tissues damage, even in not cured animals and individuals, the goal is to assess the
drug response to BZ of T. cruzi II strains isolated from children of the
Jequitinhonha Valley, state of Minas Gerais, Brazil, before treatment. Mice infected
and treated with BZ in both phases of infection were compared with the untreated and
evaluated by fresh blood examination, haemoculture, polymerase chain reaction,
conventional (ELISA) and non-conventional (FC-ALTA) serologies. In mice treated in
the acute phase, a significant decrease in parasitaemia was observed for all strains.
Positive parasitological and/or serological tests in animals treated during the acute
and chronic (95.1-100%) phases showed that most of the strains were BZ resistant.
However, beneficial effect was demonstrated because significant reduction (p <
0.05%) and/or suppression of parasitaemia was observed in mice infected with all
strains (acute phase), associated to reduction/elimination of inflammation and
fibrosis for two/eight strains. BZ offered some benefit, even in not cured animals,
what suggest that BZ use may be recommended at least for recent chronic infection of
the studied region. 相似文献
63.
64.
Eric?R. Henry Andrea Mozzarelli Cristiano Viappiani Stefania Abbruzzetti Stefano Bettati Luca Ronda Stefano Bruno William?A. Eaton 《Biophysical journal》2015,109(6):1264-1272
Trapping quaternary structures of hemoglobin in single crystals or by encapsulation in silica gels has provided a demanding set of data to test statistical mechanical models of allostery. In this work, we compare the results of those experiments with predictions of the four major allosteric models for hemoglobin: the quaternary two-state model of Monod, Wyman, and Changeux; the tertiary two-state model of Henry et al., which is the simplest extension of the Monod-Wyman-Changeux model to include pre-equilibria of tertiary as well as quaternary conformations; the structure-based model of Szabo and Karplus; and the modification of the latter model by Lee and Karplus. We show that only the tertiary two-state model can provide a near quantitative explanation of the single-crystal and gel experimental results. 相似文献
65.
66.
Cristiano S. Moura Michal Abrahamowicz Marie-Eve Beauchamp Diane Lacaille Yishu Wang Gilles Boire Paul R. Fortin Louis Bessette Claire Bombardier Jessica Widdifield John G. Hanly Debbie Feldman Walter Maksymowych Christine Peschken Cheryl Barnabe Steve Edworthy Sasha Bernatsky CAN-AIM 《Arthritis research & therapy》2015,17(1)
IntroductionUse of disease-modifying anti-rheumatic drugs (DMARDs) in rheumatoid arthritis (RA) may prevent joint damage and potentially reduce joint replacement surgeries. We assessed the association between RA drug use and joint replacement in Quebec, Canada.MethodsA cohort of new-onset RA patients was identified from Quebec’s physician billing and hospitalization databases from 2002–2011. The outcome was defined using procedure codes submitted by orthopedic surgeons. Medication use was obtained from pharmacy databases. We used alternative Cox regression models with time-dependent variables measuring the cumulative effects of past use during different time windows (one model focussing on the first year after cohort entry) for methotrexate (MTX), and other DMARDs. Models were adjusted for baseline sociodemographics, co-morbidity and prior health service use, time-dependent cumulative use of other drugs (anti-tumor necrosis factor [anti-TNF] agents, other biologics, cyclooxygenase-2 inhibitors [COXIBs], nonselective nonsteroidal antiinflammatory drugs [NSAIDs], and systemic steroids), and markers of disease severity.ResultsDuring follow-up, 608 joint replacements occurred among 11,333 patients (median follow-up: 4.6 years). The best-fitting model relied on the cumulative early use (within the first year after cohort entry) of MTX and of other DMARDs, with an interaction between MTX and other DMARDs. In this model, greater exposure within the first year, to either MTX (adjusted hazard ratio, HR = 0.95 per 1 month, 95 % confidence interval, 95 % CI 0.93-0.97) or other DMARDs (HR = 0.97, 95 % CI 0.95-0.99) was associated with longer time to joint replacement.ConclusionsOur results suggest that longer exposure to either methotrexate (MTX) or other DMARDs within the first year after RA diagnosis is associated with longer time to joint replacement surgery.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0713-3) contains supplementary material, which is available to authorized users. 相似文献67.
Cristiano S. Mota Maria G. Rivas Carlos D. Brondino Isabel Moura José J. G. Moura Pablo J. González Nuno M. F. S. A. Cerqueira 《Journal of biological inorganic chemistry》2011,16(8):1255-1268
Metal-dependent formate dehydrogenases (Fdh) from prokaryotic organisms are members of the dimethyl sulfoxide reductase family
of mononuclear molybdenum-containing and tungsten-containing enzymes. Fdhs catalyze the oxidation of the formate anion to
carbon dioxide in a redox reaction that involves the transfer of two electrons from the substrate to the active site. The
active site in the oxidized state comprises a hexacoordinated molybdenum or tungsten ion in a distorted trigonal prismatic
geometry. Using this structural model, we calculated the catalytic mechanism of Fdh through density functional theory tools.
The simulated mechanism was correlated with the experimental kinetic properties of three different Fdhs isolated from three
different Desulfovibrio species. Our studies indicate that the C–H bond break is an event involved in the rate-limiting step of the catalytic cycle.
The role in catalysis of conserved amino acid residues involved in metal coordination and near the metal active site is discussed
on the basis of experimental and theoretical results. 相似文献
68.
Enantiopure Ti(IV) complexes bearing pseudo-C(3) amino triphenolate ligands have been synthesized and characterized. The complexes bearing ortho phenyl groups act as (1)H NMR chiral solvating agent (CSA) for the stereochemical analysis of a series of sulfoxides. The coordination of a Lewis base coligand (sulfoxide) and the presence of aromatic rings are the key structural factors for the efficiency of the CSA. 相似文献
69.
Assreuy AM Pinto NV Lima Mota MR Passos Meireles AV Cajazeiras JB Nobre CB Soares PM Cavada BS 《Protein and peptide letters》2011,18(11):1107-1111
The vasorelaxant effect of the lectin of Pisum arvense (PAL) seeds was investigated in rat aorta. PAL (10-100 μg/ml) was applied on aorta rings, with or without endothelium, pre-contracted with phenylephrine (Phe; 0.1 μM). Participation of endothelium derived relaxant factors was evaluated incubating the tissue with indomethacin (10 μM), L-nitro arginine methyl ester (L-NAME, 100 μM) and tetraethylammonium (TEA, 5 mM) before addition of PAL. The role of the lectin domain was investigated by addition of PAL into tissue in presence of glucose (3x 10?? M), or N-acetyl Dglucosamine (GlcNAc; 3 x 10?? M). The importance of extracellular calcium (Ca2?e) or interaction with muscarinic receptors in the relaxant effect was evaluated by addition of PAL into aorta rings containing calcium free solution (OCa) and atropine (1 μ M), respectively. PAL induced concentration-dependent relaxation in endothelized aorta (IC50 =58.38 ± 1.87 μg/ml), which was reversed by L-NAME and glucose. The lectin effect was totally inhibited when the preparation was inserted in OCa, but not in presence of atropine. Summarizing, our data showed a relaxant effect of PAL in isolated rat aorta rings in presence of endothelium, suggestive of interaction between the lectin carbohydrate binding sites with specific receptors located in vascular endothelial cells leading to nitric oxide synthase activation. This effect seems to require Ca2?e but is independent on muscarinic receptors interaction. 相似文献
70.
Dusio GF Cardani D Zanobbio L Mantovani M Luchini P Battini L Galli V Diana A Balsari A Rumio C 《Immunology and cell biology》2011,89(5):630-639
The innate immune system is present throughout the female reproductive tract and functions in synchrony with the adaptive immune system to provide protection in a way that enhances the chances for fetal survival, while protecting against potential pathogens. Recent data show that activation of Toll-like receptor (TLR)2 and 4 by low-molecular weight hyaluronic acid (LMW-HA) in the epidermis induces secretion of the antimicrobial peptide β-defensin 2. In the present work, we show that LMW-HA induces vaginal epithelial cells to release different antimicrobial peptides, via activation of TLR2 and TLR4. Further, we found that LMW-HA favors repair of vaginal epithelial injury, involving TLR2 and TLR4, and independently from its classical receptor CD44. This wound-healing activity of LMW-HA is dependent from an Akt/phosphatidylinositol 3 kinase pathway. Therefore, these findings suggest that the vaginal epithelium is more than a simple physical barrier to protect against invading pathogens: on the contrary, this surface acts as efficient player of innate host defense, which may modulate its antimicrobial properties and injury restitution activity, following LMW-HA stimulation; this activity may furnish an additional protective activity to this body compartment, highly and constantly exposed to microbiota, ameliorating the self-defense of the vaginal epithelium in both basal and pathological conditions. 相似文献