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71.
Cavalcanti MG Mesquita JS Madi K Feijó DF Assunção-Miranda I Souza HS Bozza MT 《PloS one》2011,6(9):e25259
Background
Macrophage migration inhibitory factor (MIF) is essential for controlling parasite burden and survival in a model of systemic Toxoplasma gondii infection. Peroral T. gondii infection induces small intestine necrosis and death in susceptible hosts, and in many aspects resembles inflammatory bowel disease (IBD). Considering the critical role of MIF in the pathogenesis of IBD, we hypothesized that MIF participates in the inflammatory response induced by oral infection with T. gondii.Methodology/Principal Findings
Mif deficient (Mif−/−) and wild-type mice in the C57Bl/6 background were orally infected with T. gondii strain ME49. Mif−/− mice had reduced lethality, ileal inflammation and tissue damage despite of an increased intestinal parasite load compared to wt mice. Lack of MIF caused a reduction of TNF-α, IL-12, IFN-γ and IL-23 and an increased expression of IL-22 in ileal mucosa. Moreover, suppressed pro-inflammatory responses at the ileal mucosa observed in Mif−/− mice was not due to upregulation of IL-4, IL-10 or TGF-β. MIF also affected the expression of matrix metalloproteinase-9 (MMP-9) but not MMP-2 in the intestine of infected mice. Signs of systemic inflammation including the increased concentrations of inflammatory cytokines in the plasma and liver damage were less pronounced in Mif−/− mice compared to wild-type mice.Conclusion/Significance
In conclusion, our data suggested that in susceptible hosts MIF controls T. gondii infection with the cost of increasing local and systemic inflammation, tissue damage and death. 相似文献72.
Lígia Maria Mendonça Vieira Heitor Avelino de Abreu Richard Michael Grazul 《Inorganica chimica acta》2009,362(6):2060-1943
The fluoroquinolones constitute an important class of synthetic antimicrobial agents. The interaction between these compounds and metallic cations has been investigated primarily with the goal of identifying the functional groups directly linked to the metal. Furthermore, there has been some additional work investigating the effect of metal ions upon antibacterial activity. The vast majority of the metallic complexes reported in the literature show coordination of the fluoroquinolone through the carboxylate and the carbonyl oxygen atoms. In this work, we report the synthesis and characterization of platinum(II) complexes with ciprofloxacin, levofloxacin, ofloxacin, sparfloxacin, and gatifloxacin. The resulting complexes present the fluoroquinolone coordinated through the nitrogen atoms of the piperazine ring, which is unusual. The proposed structures were supported by spectroscopic evidence (IR, NMR, and mass spectra) as well as by theoretical studies. 相似文献
73.
Intraperitoneal but not intravenous cryopreserved mesenchymal stromal cells home to the inflamed colon and ameliorate experimental colitis 总被引:1,自引:0,他引:1
Castelo-Branco MT Soares ID Lopes DV Buongusto F Martinusso CA do Rosario A Souza SA Gutfilen B Fonseca LM Elia C Madi K Schanaider A Rossi MI Souza HS 《PloS one》2012,7(3):e33360
Background and Aims
Mesenchymal stromal cells (MSCs) were shown to have immunomodulatory activity and have been applied for treating immune-mediated disorders. We compared the homing and therapeutic action of cryopreserved subcutaneous adipose tissue (AT-MSCs) and bone marrow-derived mesenchymal stromal cells (BM-MSCs) in rats with trinitrobenzene sulfonic acid (TNBS)–induced colitis.Methods
After colonoscopic detection of inflammation AT-MSCs or BM-MSCs were injected intraperitoneally. Colonoscopic and histologic scores were obtained. Density of collagen fibres and apoptotic rates were evaluated. Cytokine levels were measured in supernatants of colon explants. For cell migration studies MSCs and skin fibroblasts were labelled with Tc-99m or CM-DiI and injected intraperitonealy or intravenously.Results
Intraperitoneal injection of AT-MSCs or BM-MSCs reduced the endoscopic and histopathologic severity of colitis, the collagen deposition, and the epithelial apoptosis. Levels of TNF-α and interleukin-1β decreased, while VEGF and TGF-β did not change following cell-therapy. Scintigraphy showed that MSCs migrated towards the inflamed colon and the uptake increased from 0.5 to 24 h. Tc-99m-MSCs injected intravenously distributed into various organs, but not the colon. Cm-DiI-positive MSCs were detected throughout the colon wall 72 h after inoculation, predominantly in the submucosa and muscular layer of inflamed areas.Conclusions
Intraperitoneally injected cryopreserved MSCs home to and engraft into the inflamed colon and ameliorate TNBS-colitis. 相似文献74.
Dettoni JL Consolim-Colombo FM Drager LF Rubira MC Souza SB Irigoyen MC Mostarda C Borile S Krieger EM Moreno H Lorenzi-Filho G 《Journal of applied physiology (Bethesda, Md. : 1985)》2012,113(2):232-236
Sleep deprivation is common in Western societies and is associated with increased cardiovascular morbidity and mortality in epidemiological studies. However, the effects of partial sleep deprivation on the cardiovascular system are poorly understood. In the present study, we evaluated 13 healthy male volunteers (age: 31 ± 2 yr) monitoring sleep diary and wrist actigraphy during their daily routine for 12 nights. The subjects were randomized and crossover to 5 nights of control sleep (>7 h) or 5 nights of partial sleep deprivation (<5 h), interposed by 2 nights of unrestricted sleep. At the end of control and partial sleep deprivation periods, heart rate variability (HRV), blood pressure variability (BPV), serum norepinephrine, and venous endothelial function (dorsal hand vein technique) were measured at rest in a supine position. The subjects slept 8.0 ± 0.5 and 4.5 ± 0.3 h during control and partial sleep deprivation periods, respectively (P < 0.01). Compared with control, sleep deprivation caused significant increase in sympathetic activity as evidenced by increase in percent low-frequency (50 ± 15 vs. 59 ± 8) and a decrease in percent high-frequency (50 ± 10 vs. 41 ± 8) components of HRV, increase in low-frequency band of BPV, and increase in serum norepinephrine (119 ± 46 vs. 162 ± 58 ng/ml), as well as a reduction in maximum endothelial dependent venodilatation (100 ± 22 vs. 41 ± 20%; P < 0.05 for all comparisons). In conclusion, 5 nights of partial sleep deprivation is sufficient to cause significant increase in sympathetic activity and venous endothelial dysfunction. These results may help to explain the association between short sleep and increased cardiovascular risk in epidemiological studies. 相似文献
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This paper describes a biomolecular classification methodology based on multilayer perceptron neural networks. The system developed is used to classify enzymes found in the Protein Data Bank. The primary goal of classification, here, is to infer the function of an (unknown) enzyme by analysing its structural similarity to a given family of enzymes. A new codification scheme was devised to convert the primary structure of enzymes into a real-valued vector. The system was tested with a different number of neural networks, training set sizes and training epochs. For all experiments, the proposed system achieved a higher accuracy rate when compared with profile hidden Markov models. Results demonstrated the robustness of this approach and the possibility of implementing fast and efficient biomolecular classification using neural networks. 相似文献
78.
Wanessa Teixeira Gomes Barreto Gisele Braziliano de Andrade Lúcio André Viana Grasiela Edith de Oliveira Porfírio Filipe Martins Santos Alessandra Cabral Perdomo Jéssica Soares do Carmo Alanderson Rodrigues da Silva Taynara Rocha Maltezo Heitor Miraglia Herrera 《Systematic parasitology》2018,95(4):383-389
Despite the great diversity of coccidians, to our knowledge, no coccidian infections have been described in Oecomys spp. In this context, we examined Oecomys mamorae Thomas (Rodentia: Cricetidae) from the Brazilian Pantanal for infections with enteric coccidia. Nine individuals were sampled, and one was found to be infected. The oöcysts were recovered through centrifugal flotation in sugar solution. Using morphological and morphometric features, we described a new species of Cystoisospora Frenkel, 1977. Sporulated oöcysts were ovoidal 20.0–29.1 × 16.4–23.2 (26.7 × 21.2) µm and contained two sporocysts, 12.9–19.1 × 9.4–13.9 (16.4 × 12.4) µm, each with four banana-shaped sporozoites. Polar granule and oöcyst residuum were both absent. We documented the developmental forms in the small intestine and described the histopathological lesions in the enteric tract. Our results indicate that the prevalence of Cystoisospora mamorae n. sp. in O. mamorae is low, and tissue damage in the enteric tract is mild, even in the presence of coccidian developmental stages. 相似文献
79.
Heitor G. Araújo-Filho Lucindo J. Quintans-Júnior André S. Barreto Jackson R. G. S. Almeida Rosana S. S. Barreto Jullyana S. S. Quintans 《Neurochemical research》2016,41(4):647-658
Peripheral nerve injury (PNI) is a serious public health problem that is linked with motor, sensory and autonomic deficits. Given the fact that this type of disorder leads to a decreased quality of life in most patients and adherence of available drugs is limited and have adverse effects, we investigated the efficacy of natural products in a PNI model. The search terms plants, medicinal, nerve regeneration, nerve crush, sciatic nerve as well as MeSH terms or free-text words were used to retrieve English language articles in PubMed, Scopus, Web of Science and LILACS published until July 2015. After sciatic nerve crush, natural products have improved significantly motor performance, sensory function and electrical conductance measured over weeks. Among the pharmacological targets suggested by the action of natural products, there were citations on the activation of the antiapoptotic signaling pathway, modulation in the expression of pro-inflammatory cytokines and neurotrophic factors. The systematic review provides scientific evidence that natural products are pharmacologically effective in the treatment of PNI such as sciatic nerve crush. 相似文献
80.
Agronomic and environmental implications of sugarcane straw removal: a major review 总被引:1,自引:0,他引:1 下载免费PDF全文
João Luís Nunes Carvalho Roberta Corrêa Nogueirol Lauren Maine Santos Menandro Ricardo de Oliveira Bordonal Clovis Daniel Borges Heitor Cantarella Henrique C. Junqueira Franco 《Global Change Biology Bioenergy》2017,9(7):1181-1195
Large‐scale bioenergy demand has triggered new approaches to straw management in Brazilian sugarcane fields. With the progressive shift from a burned to a nonburned harvest system, most of the straw presently retained on the soil surface has become economically viable feedstock for bioenergy production. The trade‐offs between the need to preserve soil quality and produce more bioenergy have been the subject of intense discussion. This study presents a synthesis of available information on the magnitude of the main impacts of straw removal from sugarcane fields for bioenergy production and therefore represents an easily available resource to guide management decisions on the recommended amount of straw to be maintained on the field to take advantage of the agronomic, environmental, and industrial benefits. Crop residues remaining on sugarcane fields provide numerous ecosystem services including nutrient recycling, soil biodiversity, water storage, carbon accumulation, control of soil erosion, and weed infestation. Furthermore, several studies reported higher sugarcane production under straw retention on the field, while few suggest that straw may jeopardize biomass production in cold regions and under some specific soil conditions. Pest control is among the parameters favored by straw removal, while N2O emissions are increased only if straw is associated with the application of N fertilizer and vinasse. An appropriate recommendation, which is clearly site specific, should be based on a minimum mass of straw on the field to provide those benefits. Overall, this review indicates that most of the agronomic and environmental benefits are achieved when at least 7 Mg ha?1 of dry straw is maintained on the soil surface. However, modeling efforts are of paramount importance to assess the magnitude and rates of straw removal considering the several indicators involved in this complex equation, so that an accurate straw recovery rate could be provided to producers and industry toward greater sustainability. 相似文献