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1.
Effect of a high-intensity static magnetic field on sciatic nerve regeneration in the rat 总被引:2,自引:0,他引:2
P G Cordeiro B R Seckel C D Miller P T Gross R E Wise 《Plastic and reconstructive surgery》1989,83(2):301-308
The effect of a high-intensity static magnetic field on peripheral nerve regeneration is evaluated in rat sciatic nerve. Forty-four rats underwent sciatic nerve repair using polyethylene nerve guides. Postoperatively, the animals were exposed to a 1-tesla magnetic field for 12 hours per day for 4 weeks with appropriate controls. Our results demonstrate that a 1-tesla static magnetic field has no statistically significant effect on nerve regeneration as determined by myelinated axon counts and electrophysiologic studies. Also, the specific orientation of the sciatic nerve with respect to the magnetic field has no influence on axonal growth or nerve conduction. Periods of restraint of 12 hours per day for 4 weeks significantly inhibit weight gain but have no effect on peripheral nerve regeneration. 相似文献
2.
Ochratoxin A was produced, at concentrations of about 200 mg kg1 of dry beans (Phaseolus vulgaris L.) of each of five Brazilian commercial varieties. Both intact and decorticated kernels of the varieties Preto, Branco, Rosinha, Roxo and Carioca (22% moisture) were inoculated withAspergillus alutaceous and incubated at 25°C for 28 days. Results from thin-layer and column chromatography, mass, infrared, 1H-nuclear magnetic resonance and UV-spectrometry showed that 1) the common bean is a highly stimulatory substrate for the bioproduction of ochratoxin A and 2) the putative toxin extracted by the method of Soares & Rodriguez-Amaya was in fact ochratoxin A. Removal of the seed coat resulted in increased OTA production for all varieties, particularly for the Rosinha, Roxo and Carioca. 相似文献
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4.
Daniela S. Carneiro-Torres Inês Cordeiro Ana Maria Giulietti Paul E. Berry Ricarda Riina 《Brittonia》2011,63(1):122-132
While conducting a floristic inventory of Croton from the Brazilian Caatinga, three new species were discovered. Croton arenosus, Croton glandulosobracteatus, and Croton harleyi are described and illustrated here. Based on morphological characters, Croton glandulosobracteatus is proposed to belong to section Barhamia, and C. arenosus and C. harleyi to section Geiseleria. 相似文献
5.
N. J. Cordeiro J. C. Lovett E. Mulungu G. G. Maina J. H. Gerstle 《Biodiversity and Conservation》2006,15(3):971-983
The Lower Kihansi Hydropower Project in southern Tanzania caused the diversion of the Kihansi River from the Kihansi Gorge
in the year 2000. By sampling the understorey avifauna prior to diversion, we examined (i) whether the adjacent Udagaje Gorge
was an adequate control for observations in the Kihansi Gorge; (ii) which species of conservation interest occurred; and,
(iii) which season best suited annual monitoring. Species composition and capture rates at three and two elevational transects
in the Kihansi Gorge and Udagaje Gorge, respectively, confirmed that Udagaje had a comparable avifaunal assemblage to Kihansi.
The cold season was most appropriate for population monitoring because >2 times more individuals were captured in the cold
than hot season at both gorges, and at least four altitudinal migrants were present in the cold but not hot season. Post-diversion
sampling revealed that only the Upper Kihansi transect suffered a significant decrease in number of individuals, a result
that was driven largely by a decline in the Little Greenbul, Andropadus virens. This transect is closest to the Kihansi waterfall and associated spray zone which were lost after river diversion. Lack
of differences in bird communities at other transects after diversion illustrates that early post-diversion effects on birds
are probably concentrated near the base of the main falls. Together with studies of other biota in Kihansi, we propose that
long-term monitoring is necessary to understand the factors that regulate changes in species composition of this threatened
forest site. 相似文献
6.
Mónica Oleastro Rita Cordeiro Armelle Ménard Yoshio Yamaoka Dulciene Queiroz Francis Mégraud Lurdes Monteiro 《BMC microbiology》2009,9(1):248
Background
The homB gene is a Helicobacter pylori disease-marker candidate, strongly associated with peptic ulcer disease, while homA, its paralogue gene with 90% sequence identity, is correlated with non-ulcer dyspepsia. The HomB encoded outer membrane protein was shown to contribute to the proinflammatory properties of H. pylori and also to be involved in bacterial adherence. 相似文献7.
Comment on ‘Island biogeography: patterns of marine shallow‐water organisms’ by Hachich et al., Journal of Biogeography (2015)
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Sérgio P. Ávila Ricardo Cordeiro Ricardo Haroun Peter Wirtz 《Journal of Biogeography》2016,43(12):2515-2516
In a recent article, Hachich et al. (2015, Journal of Biogeography, 42 , 1871–1882) studied the large‐scale biogeographical patterns of the species–area, species–island age and species–isolation relationships associated with marine shallow‐water groups (reef fish, gastropods and seaweeds) from 11 Atlantic archipelagos. We here express our concerns regarding the data accuracy used to compute the different models that tested the null hypothesis of species richness being independent of the selected variables. In our commentary, we focus mainly on the use of out‐of‐date checklists of gastropod and seaweed species from different archipelagos, but we also point out inaccuracies in some island age estimates and explain our disagreement with the use of the 200 m depth limit for the shallow‐water gastropods and seaweeds. 相似文献
8.
Fiuza SM Gomes C Teixeira LJ Girão da Cruz MT Cordeiro MN Milhazes N Borges F Marques MP 《Bioorganic & medicinal chemistry》2004,12(13):3581-3589
The antiproliferative and cytotoxic properties of polyphenolic acid derivatives, structurally related with the natural models caffeic and gallic acids, have been tested in human cervix adenocarcinoma cells (HeLa). Simultaneous structural information was obtained for these compounds through theoretical ab initio methods. This study was conducted for the following esters: methyl caffeate (MC, 1), propyl caffeate (PC, 2), octyl caffeate (OC, 3), methyl gallate (MG, 4), propyl gallate (PG, 5) and octyl gallate (OG, 6). A significant growth-inhibition effect was assessed for some of these compounds, clearly dependent on their structural characteristics. Marked structure-activity relationships (SARs)--namely the number of hydroxyl ring substituents--were found to rule the biological effect of such systems. 相似文献
9.
J Vitoriano-Souza Nd Moreira A Teixeira-Carvalho CM Carneiro FA Siqueira PM Vieira RC Giunchetti SA Moura RT Fujiwara MN Melo AB Reis 《PloS one》2012,7(7):e40745
Vaccine adjuvants are substances associated with antigens that are fundamental to the formation of an intense, durable, and fast immune response. In this context, the use of vaccine adjuvants to generate an effective cellular immune response is crucial for the design and development of vaccines against visceral leishmaniasis. The objective of this study was to evaluate innate inflammatory response induced by the vaccine adjuvants saponin (SAP), incomplete Freund's adjuvant (IFA), and monophosphoryl lipid A (MPL). After a single dose of adjuvant was injected into the skin of mice, we analyzed inflammatory reaction, selective cell migration, and cytokine production at the injection site, and inflammatory cell influx in the peripheral blood. We found that all vaccine adjuvants were able to promote cell recruitment to the site without tissue damage. In addition, they induced selective migration of neutrophils, macrophages, and lymphocytes. The influx of neutrophils was notable at 12 h in all groups, but at other time points it was most evident after inoculation with SAP. With regard to cytokines, the SAP led to production of interleukin (IL)-2, IL-6, and IL-4. IFA promoted production of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, IL-6, IL-17, IL-4, and IL-10. We also observed that MPL induced high production of IL-2, TNF-α, and IFN-γ, in addition to IL-6, IL-17, and IL-10. In peripheral blood, values of certain cell populations in the local response changed after stimulation. Our data demonstrate that the three vaccine adjuvants stimulate the early events of innate immune response at the injection site, suggesting their ability to increase the immunogenicity of co-administered antigens. Moreover, this work provides relevant information about elements of innate and acquired immune response induced by vaccine adjuvants administered alone. 相似文献
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