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51.
do Prado Joyce Rodrigues Rocha Rita G. Bissoli-Silva Heitor Mendes-Oliveira Ana Cristina Pontes Regeane C. L. de A Maués Paula Cristina R. Costa Leonora Pires 《Biodiversity and Conservation》2022,31(11):2683-2697
Biodiversity and Conservation - The Amazon region is a mosaic of distinct areas of endemism (AoE), each with its evolutionary relationships and biotic assemblages. Among them, the Tapajós AoE... 相似文献
52.
Márcia Almeida Araújo Alexandre Silvana Gomes Benzecry Andre Machado Siqueira Sheila Vitor-Silva Gisely Cardoso Melo Wuelton Marcelo Monteiro Heitor Pons Leite Marcus Vinícius Guimar?es Lacerda Maria das Gra?as Costa Alecrim 《PLoS neglected tropical diseases》2015,9(4)
Background
The relationship between malaria and undernutrition is controversial and complex. Synergistic associations between malnutrition and malaria morbidity and mortality have been suggested, as well as undernutrition being protective against infection, while other studies found no association. We sought to evaluate the relationship between the number of malaria episodes and nutritional statuses in a cohort of children below 15 years of age living in a rural community in the Brazilian Amazon.Methodology/Principal Findings
Following a baseline survey of clinical, malaria and nutritional assessment including anthropometry measurements and hemoglobin concentration, 202 children ranging from 1 month to 14 years of age were followed for one year through passive case detection for malaria episodes. After follow-up, all children were assessed again in order to detect changes in nutritional indicators associated with malaria infection. We also examined the risk of presenting malaria episodes during follow-up according to presence of stunting at baseline. Children who suffered malaria episodes during follow-up presented worse anthropometric parameters values during this period. The main change was a reduction of the linear growth velocity, associated with both the number of episodes and how close the last or only malaria episode and the second anthropometric assessment were. Changes were also observed for indices associated with chronic changes, such as weight-for-age and BMI-for-age, which conversely, were more frequently observed in children with the last or only episode occurring between 6 and 12 months preceding the second nutritional assessment survey. Children with inadequate height-for-age at baseline (Z-score < -2) presented lower risk of suffering malaria episodes during follow-up as assessed by both the log-rank test (p =0.057) and the multivariable Cox-proportional hazards regression (Hazard Ratio = 0.31, 95%CI [0.10; 0.99] p=0.049).Conclusions
Malaria was associated with impaired nutritional status amongst children in an endemic area of the Western Brazilian Amazon where P. vivax predominates. Our data all supports that the association presents differential effects for each age group, suggesting distinct pathophysiology pathways. We were also able to demonstrate that undernourishment at baseline was protective to malaria during follow-up. These findings support an intriguing interaction between these conditions in the rural Amazon and the need for a more integrative approach by health systems in endemic areas. 相似文献53.
Lung production of platelet-activating factor acetylhydrolase in oleic acid-induced acute lung injury 总被引:11,自引:0,他引:11
Salluh JI Pino AV Silva AR Gomes RN Souza HS e Silva JR Jandre FC Giannella-Neto A Zimmerman GA Stafforini DM Prescott SM Castro-Faria-Neto HC Bozza PT Bozza FA 《Prostaglandins, leukotrienes, and essential fatty acids》2007,77(1):1-8
Platelet-activating factor (PAF) is a proinflammatory mediator that plays a central role in acute lung injury (ALI). PAF- acetylhydrolases (PAF-AHs) terminate PAF's signals and regulate inflammation. In this study, we describe the kinetics of plasma and bronchoalveolar lavage (BAL) PAF-AH in the early phase of ALI. Six pigs with oleic acid induced ALI and two healthy controls were studied. Plasma and BAL samples were collected every 2h and immunohistochemical analysis of PAF-AH was performed in lung tissues. PAF-AH activity in BAL was increased at the end of the experiment (BAL PAF-AH Time 0=0.001+/-0.001 nmol/ml/min/g vs Time 6=0.031+/-0.018 nmol/ml/min/g, p=0.04) while plasma activity was not altered. We observed increased PAF-AH staining of macrophages and epithelial cells in the lungs of animals with ALI but not in healthy controls. Our data suggest that increases in PAF-AH levels are, in part, a result of alveolar production. PAF-AH may represent a modulatory strategy to counteract the excessive pro-inflammatory effects of PAF and PAF-like lipids in lung inflammation. 相似文献
54.
Fortini Evandro Alexandre Batista Diego Silva de Castro Kamila Motta Silva Tatiane Dulcineia Felipe Sérgio Heitor Sousa Correia Ludmila Nayara Freitas Chagas Kristhiano Farias Letícia Monteiro Leite João Paulo Viana Otoni Wagner Campos 《Plant Cell, Tissue and Organ Culture》2020,142(3):595-611
Plant Cell, Tissue and Organ Culture (PCTOC) - Photoperiod regulates different morphophysiological processes in plants, directly impacting photosynthetic performance and, consequently, primary and... 相似文献
55.
Samanta Etel Treiger Borborema Jo?o Alberto Osso Junior Heitor Franco de Andrade Junior Nanci do Nascimento 《Memórias do Instituto Oswaldo Cruz》2013,108(5):623-630
Pentavalent antimonials such as meglumine antimoniate (MA) are the
primary treatments for leishmaniasis, a complex disease caused by protozoan
parasites of the genus Leishmania . Despite over 70 years of
clinical use, their mechanisms of action, toxicity and pharmacokinetics have not
been fully elucidated. Radiotracer studies performed on animals have the
potential to play a major role in pharmaceutical development. The aims of this
study were to prepare an antimony radiotracer by neutron irradiation of MA and
to determine the biodistribution of MA in healthy and Leishmania
(Leishmania) infantum chagasi-infected mice. MA
(Glucantime(r)) was neutron irradiated inside the IEA-R1 nuclear
reactor, producing two radioisotopes, 122Sb and 124Sb, with high radionuclidic
purity and good specific activity. This irradiated compound presented
anti-leishmanial activity similar to that of non-irradiated MA in both in vitro
and in vivo evaluations. In the biodistribution studies, healthy mice showed
higher uptake of antimony in the liver than infected mice and elimination
occurred primarily through biliary excretion, with a small proportion of the
drug excreted by the kidneys. The serum kinetic curve was bi-exponential, with
two compartments: the central compartment and another compartment associated
with drug excretion. Radiotracers, which can be easily produced by neutron
irradiation, were demonstrated to be an interesting tool for answering several
questions regarding antimonial pharmacokinetics and chemotherapy. 相似文献
56.
Noriko A. Cassman Johnny R. Soares Agata Pijl Késia S. Lourenço Johannes A. van Veen Heitor Cantarella Eiko E. Kuramae 《Environmental microbiology》2019,21(4):1241-1254
The nitrification inhibitors (NIs) 3,4-dimethylpyrazole (DMPP) and dicyandiamide (DCD) can effectively reduce N2O emissions; however, which species are targeted and the effect of these NIs on the microbial nitrifier community is still unclear. Here, we identified the ammonia oxidizing bacteria (AOB) species linked to N2O emissions and evaluated the effects of urea and urea with DCD and DMPP on the nitrifying community in a 258 day field experiment under sugarcane. Using an amoA AOB amplicon sequencing approach and mining a previous dataset of 16S rRNA sequences, we characterized the most likely N2O-producing AOB as a Nitrosospira spp. and identified Nitrosospira (AOB), Nitrososphaera (archaeal ammonia oxidizer) and Nitrospira (nitrite-oxidizer) as the most abundant, present nitrifiers. The fertilizer treatments had no effect on the alpha and beta diversities of the AOB communities. Interestingly, we found three clusters of co-varying variables with nitrifier operational taxonomic units (OTUs): the N2O-producing AOB Nitrosospira with N2O, NO3−, NH4+, water-filled pore space (WFPS) and pH; AOA Nitrososphaera with NO3−, NH4+ and pH; and AOA Nitrososphaera and NOB Nitrospira with NH4+, which suggests different drivers. These results support the co-occurrence of non-N2O-producing Nitrososphaera and Nitrospira in the unfertilized soils and the promotion of N2O-producing Nitrosospira under urea fertilization. Further, we suggest that DMPP is a more effective NI than DCD in tropical soil under sugarcane. 相似文献
57.
58.
Antimicrobial and mechanical properties of acrylic resins with incorporated silver-zinc zeolite - part I 总被引:1,自引:0,他引:1
Objective: The purpose of this in vitro study was to evaluate the antimicrobial activity of acrylic resins containing different percentages of silver and zinc zeolite, and to assess whether the addition of zeolite alters the flexural and impact strength of the resins. Background: The characteristics of acrylic resins support microorganism development that can threaten the health of the dentures user. Material and methods: A microwave‐polymerised (Onda‐Cryl) and two heat‐polymerised (QC20 and Lucitone 550) acrylic resins were used. The materials were handled according to the manufacturers’ instructions. Fifty rectangular‐shaped specimens (8 × 10 × 4mm) were fabricated from each resin and assigned to 5 groups (n = 10) according to their percentage of Irgaguard B5000 silver–zinc zeolite (0%– control, 2.5%, 5.0%, 7.5% and 10%). Flexural strength and Izod impact strength were evaluated. The antimicrobial activity against two strains of Candida albicans and two strains of Streptococcus mutans was assessed by agar diffusion method. Data were analysed statistically by one‐way anova and Tukey’s test at 5% significance level. Results: The addition of 2.5% of Irgaguard B5000 to the materials resulted in antimicrobial activity against all strains. Flexural strength decreased significantly with the addition of 2.5% (QC20 and Lucitone 550) and 5.0% (Onda‐Cryl) of Irgaguard B5000. The impact strength decreased significantly with the addition of 2.5% (Lucitone 550) and 5.0% (QC20 and Onda‐Cryl) of zeolite. Conclusion: The addition of silver–zinc zeolite to acrylic resins yields antimicrobial activity, but may affect negatively the mechanical properties, depending on the percentage of zeolite. 相似文献
59.
Prostaglandin E2 and dexamethasone regulate eosinophil differentiation and survival through a nitric oxide- and CD95-dependent pathway. 总被引:1,自引:0,他引:1
Carla P Jones Heitor A Paula Neto Jamil Assreuy B Boris Vargaftig Maria Ignez Gaspar Elsas P Xavier Elsas 《Nitric oxide》2004,11(2):184-193
Apoptosis, involving both CD95/CD95L interactions and their modulation by nitric oxide (NO), is central to regulation of mature eosinophil numbers. However, its role in regulating eosinophil production from bone-marrow precursors is unknown. We examined the effects of prostaglandin E2 (PGE2) and dexamethasone on eosinophil differentiation and survival in murine bone-marrow cultures, and their relationship to: NO production as well as CD95/CD95L-dependent apoptosis. Bone-marrow cultures were established with IL-5, alone or in association with PGE2, dexamethasone or both. PGE2 (10(-7)M) inhibited eosinophil differentiation by selectively inducing apoptosis in developing eosinophils. Dexamethasone (10(-7)M) protected developing eosinophils from PGE2-induced apoptosis. Since dexamethasone prevents induction of nitric oxide synthase (NOS), we evaluated the role of NO in the effects of both PGE2 and dexamethasone. NO donors (SNAP and SNP) down-modulated eosinophil precursor responses to IL-5. SNAP induced apoptosis through a dexamethasone-resistant mechanism. The NOS inhibitors, Nomega-nitro-L-arginine and aminoguanidine, blocked the effects of PGE2 on developing eosinophils. PGE2 was ineffective in bone-marrow from knockout mice lacking inducible NOS. PGE2 up-regulated CD95 and CD95L expression in developing eosinophils. Neither PGE2 nor SNAP were effective in cultures from CD95L-deficient gld mice. These data suggest that PGE2 induces apoptosis in developing eosinophils through inducible NOS, leading to NO-dependent activation of the CD95L/CD95 pathway, while dexamethasone antagonizes the effects of PGE2 on the same targets. 相似文献
60.
Elias Silva dos Santos Dermeval Heitor Souza Gritta Jailton Souza de Almeida 《Molecular simulation》2016,42(8):605-610
The dynamic behaviour of adenosine triphosphate sulfurylase (ATPs) is analysed to investigate its energetic interactions with inhibitors recently studied theoretically and tested experimentally. The interactions between ATPs and three inhibitors namely, 2,2′-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS), butylated hydroxytoluene (BHT), and 3-tert-butyl-4-hydroxyanisole (BHA) in aqueous solution were studied via molecular dynamics simulations. The results of the absolute and relative free energies reveal the existence of synergism in the system. Additionally, the system demonstrates strong steric effect between ABTS and BHA that is not only due to the size of these inhibitors but also their surroundings. 相似文献