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31.
Zampronio AR Melo MC Silva CA Pelá IR Hopkins SJ Souza GE 《Mediators of inflammation》1994,3(5):365-373
The aim of this study was to investigate the pyrogenic activity of factor(s) released by rat peritoneal macrophages following a brief stimulation with LPS. The effect of this factor on the number of circulating leukocytes and serum Fe, Cu and Zn levels, was also evaluated. The possibility that the content of interleukin (IL)-1beta, IL-6 and tumour necrosis factor (TNF) in the supernatant could explain the observations was investigated. Supernatant produced over a period of 1 h by peritoneal macrophages, following a 30 min incubation with LPS at 37 degrees C, was ultrafiltered through a 10 000 MW cut-off Amicon membrane, sterilized, and concentrated 2.5, 5, 10 and 20 times. The intravenous (i.v.) injection of this supernatant induced a concentration-dependent fever in rats with a maximal response at 2 h. The pyrogenic activity was produced by macrophages elicited with thioglycollate and by resident cells. The supernatants also induced neutrophilia and reduction in Fe and Zn 6 h after the injection. Absence of activity in boiled supernatants, or supernatants from macrophages incubated at 4 degrees C with LPS, indicates that LPS was not responsible for the activity. In vitro treatment with indomethacin (Indo), dexamethasone (Dex), or cycloheximide (Chx) did not modify the release of pyrogenic activity into the supernatant or its effects on the reduction in serum metal levels. Although Chx abolished the production of mediator(s) inducing neutrophilia, and Dex reduced the induction of IL-1beta, TNF and IL-6, injection of the highest concentration of these cytokines detected in the supernatants did not induce fever. In vivo treatment with Dex, but not Indo, abolished the fever induced by the supernatant. These results suggest that macrophages contain pre-formed pyrogenic mediator(s), not related to IL-1beta, IL-6 or TNF, that acts indirectly and independently of prostaglandtn. It also seems likely that the pyrogenic activity is related to the factor responsible for the reduction of serum Fe and Zn levels, but not the neutrophilia. 相似文献
32.
Karina Motta Melo Ingrid Reale Alves Julio Cesar Pieczarka José Augusto de Oliveira David Cleusa Yoshiko Nagamachi Cesar Koppe Grisolia 《Genetics and molecular biology》2013,36(3):425-429
The frequency of spontaneous micronucleus (MN) formation in fish species needs to be determined to evaluate their usefulness for genotoxic biomonitoring. The definition of a good bioindicator takes into account the current knowledge of its metabolic traits as well as other factors including its feeding behavior and relationship to the environment. In this study, we compared the basal frequencies of micronucleated erythrocytes and nuclear abnormalities (NA) among different species of the fish Order Gymnotiformes (Rhamphichthys marmoratus, Steatogenys elegans, Sternopygus macrurus, Parapteronotus hasemani, Gymnotus mamiraua, Gymnotus arapaima, Brachyhypopomus beebei, Brachyhypopomus n. sp. BENN) sampled in several localities of the Eastern Amazon. A baseline of MN and NA frequency in these fish was determined, enabling the identification of potentially useful species as models for genotoxicity studies. Only one impacted sample collected at a site in the River Caripetuba showed a significant number of NAs, which may be due to the release of wastewater by neighbouring mining industries and by the burnt fuel released by the small boats used by a local community. Our results may provide support for further studies in areas of the Eastern Amazon affected by mining, deforestation and other anthropogenic activities. 相似文献
33.
Maternal protein restriction during gestation and lactation in the rat results in increased brain levels of kynurenine and kynurenic acid in their adult offspring 下载免费PDF全文
34.
35.
The Brazilian Atlantic Forest is a Biodiversity Hotspot, yet many biological groups in this biome are poorly known. We compiled
information on the diversity of Atlantic Forest tiger moths (Arctiidae) and assessed the resemblance among localities, whether
arctiid assemblages are concordant with major vegetation types, and the importance of environmental factors in structuring
the variation among assemblages. Additionally, we developed a procedure composed of subsampling and procrustean analysis to
assess the robustness of the results from community composition ordinations when localities differ in species richness. To
do this, we built a database from specimens deposited in the ten most important Brazilian entomological collections, and mapped
species richness in one-degree latitude/longitude grid cells. We employed Principal Coordinates Analysis to assess similarities
among the best-sampled localities. We obtained 8,667 records including 1,193 species, representing 60 and 20% of the estimated
Brazilian and Neotropical faunas, respectively. Our subsampling procedure indicated that the ordination was not greatly affected
by differences in species richness, and was congruent with major vegetation types. Lowland localities on the seacoast were
quite distinct in species composition. A second group included localities in montane areas in the southeast part of the biome.
The last group included localities in the southern region and those with Araucaria forests, and was associated with long distances
from the ocean, even distribution of precipitation throughout the year, and large annual temperature ranges. 相似文献
36.
de Aquino TM Liesen AP da Silva RE Lima VT Carvalho CS de Faria AR de Araújo JM de Lima JG Alves AJ de Melo EJ Góes AJ 《Bioorganic & medicinal chemistry》2008,16(1):446-456
In the present communication, a new series of 2-[(phenylmethylene)hydrazono]-4-oxo-3-phenyl-5-thiazolidineacetic acids (2a-p) have been synthesized. Benzaldehyde 4-phenyl-3-thiosemicarbazones substituted (1a-p) were also obtained and used as intermediate to give the title compounds. All synthesized compounds were characterized by IR, (1)H and (13)C NMR. The in vitro anti-Toxoplasma gondii activity of 1a-p and 2a-p was evaluated. The 4-thiazolidinones (2a-p) were screened for their in vitro antimicrobial activity. For anti-Toxoplasma gondii activity, in general, all compounds promoted decreases in the percentage of infected cells leading to parasite elimination. These effects on intracellular parasites also caused a decrease in the mean number of tachyzoites. In addition, most of the 4-thiazolidinones showed more effective toxicity against intracellular parasites, with IC(50) values ranging from 0.05 to 1 mM. According to results of antimicrobial activity, compounds 2f, 2l, and 2p showed best activity against Mycobacterium luteus, 2c was more active against Mycobacterium tuberculosis, and 2g, 2l, and 2n showed same activity as nistatin (standard drug) against Candida sp. (4249). 相似文献
37.
Paulo FP Pimenta Alessandra S Orfano Ana C Bahia Ana PM Duarte Claudia M Ríos-Velásquez Fabrício F Melo Felipe AC Pessoa Giselle A Oliveira Keillen MM Campos Luis Martínez Villegas Nilton Barnabé Rodrigues Rafael Nacif-Pimenta Rejane C Sim?es Wuelton M Monteiro Rogerio Amino Yara M Traub-Cseko José BP Lima Maria GV Barbosa Marcus VG Lacerda Wanderli P Tadei Nágila FC Secundino 《Memórias do Instituto Oswaldo Cruz》2015,110(1):23-47
In the Americas, areas with a high risk of malaria transmission are mainly located in
the Amazon Forest, which extends across nine countries. One keystone step to
understanding the Plasmodium life cycle in Anopheles species from the Amazon Region
is to obtain experimentally infected mosquito vectors. Several attempts to colonise
Ano- pheles species have been conducted, but with only short-lived success or no
success at all. In this review, we review the literature on malaria transmission from
the perspective of its Amazon vectors. Currently, it is possible to develop
experimental Plasmodium vivax infection of the colonised and field-captured vectors
in laboratories located close to Amazonian endemic areas. We are also reviewing
studies related to the immune response to P. vivax infection of Anopheles aquasalis,
a coastal mosquito species. Finally, we discuss the importance of the modulation of
Plasmodium infection by the vector microbiota and also consider the anopheline
genomes. The establishment of experimental mosquito infections with Plasmodium
falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide
interesting models for studying malaria in the Amazonian scenario is important.
Understanding the molecular mechanisms involved in the development of the parasites
in New World vectors is crucial in order to better determine the interaction process
and vectorial competence. 相似文献
38.
Unfolding kinetics of beta-lactoglobulin induced by surfactant and denaturant: a stopped-flow/fluorescence study 下载免费PDF全文
The beta-->alpha transition of beta-lactoglobulin, a globular protein abundant in the milk of several mammals, is investigated in this work. This transition, induced by the cationic surfactant dodecyltrimethylammonium chloride (DTAC), is accompanied by partial unfolding of the protein. In this work, unfolding of bovine beta-lactoglobulin in DTAC is compared with its unfolding induced by the chemical denaturant guanidine hydrochloride (GnHCl). The final protein states attained in the two media have quite different secondary structure: in DTAC the alpha-helical content increases, leading to the so-called alpha-state; in GnHCl the amount of ordered secondary-structure decreases, resulting in a random coil-rich final state (denatured, or D, state). To obtain information on both mechanistic routes, in DTAC and GnHCl, and to characterize intermediates, the kinetics of unfolding were investigated in the two media. Equilibrium and kinetic data show the partial accumulation of an on-pathway intermediate in each unfolding route: in DTAC, an intermediate (I(1)) with mostly native secondary structure but loose tertiary structure appears between the native (beta) and alpha-states; in GnHCl, another intermediate (I(2)) appears between states beta and D. Kinetic rate constants follow a linear Chevron-plot representation in GnHCl, but show a more complex mechanism in DTAC, which acts like a stronger binding species. 相似文献
39.
Lynch LF Lynch MI Ferreira RS Vasconcelos MS Melo N Ferreira S Malagueño E 《Memórias do Instituto Oswaldo Cruz》2011,106(5):625-628
Ocular toxoplasmosis can result in recurrent uveitis. Studies have shown that a correlation between active ocular toxoplasmosis and the presence of anti-Toxoplasma gondii secretory IgA (SIgA) in tears. This study compares anti-T. gondii SIgA levels in patients' tears during the acute and inactive phases of toxoplasmic uveitis. Twenty-nine positive tear specific SIgA for T. gondii patients with acute toxoplasmic uveitis were selected and were followed-up for at least two years, when the anti-T. gondii SIgA tears levels were determined. Specific SIgA for T. gondii was negative in 22 patients (75.86%) and positive in seven patients (24.13%) of whom six (85.7%) were followed over three years. Average SIgA levels during the acute phase are 1.54 and decrease significantly to 0.72 (p = 0.0001) during the inactive phase of disease. Because anti-T. gondii SIgA in the tear is negative in 75.86% of patients after the acute phase of infection, T. gondii SIgA levels may be used as a complementary diagnostic marker for active ocular toxoplasmosis. 相似文献
40.
da Silva AJ Coelho AL Simas AB Moraes RA Pinheiro DA Fernandes FF Arruda EZ Costa PR Melo PA 《Bioorganic & medicinal chemistry letters》2004,14(2):431-435
Edunol (3), a pterocarpan isolated from Harpalyce brasiliana, a plant used in the northeast of Brazil against snakebites, was obtained by synthesis and showed antimyotoxic, antiproteolytic and PLA2 inhibitor properties. These proprieties could be improved through the synthesis of a bioisoster (5), where the prenyl group was replaced by the benzyl group. 相似文献