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991.
Samara R.B. Damasceno Francisco Rodrigo A.M. Oliveira Nathalia S. Carvalho Camila F.C. Brito Irismara S. Silva Francisca Beatriz M. Sousa Renan O. Silva Damião P. Sousa André Luiz R. Barbosa Rivelilson M. Freitas Jand-Venes R. Medeiros 《Life sciences》2014
Aims
The present study aimed to investigate the potential anti-inflammatory and anti-nociceptive effects of carvacryl acetate, a derivative of carvacrol, in mice.Main methods
The anti-inflammatory activity was evaluated using various phlogistic agents that induce paw edema, peritonitis model, myeloperoxidase (MPO) activity, pro and anti-inflammatory cytokine levels. Evaluation of antinociceptive activity was conducted through acetic acid-induced writhing, hot plate test, formalin test, capsaicin and glutamate tests, as well as evaluation of motor performance on rotarod test.Key findings
Pretreatment of mice with carvacryl acetate (75 mg/kg) significantly reduced carrageenan-induced paw edema (P < 0.05) when compared to vehicle-treated group. Likewise, carvacryl acetate (75 mg/kg) strongly inhibited edema induced by histamine, serotonin, prostaglandin E2 and compound 48/80. In the peritonitis model, carvacryl acetate significantly decreased total and differential leukocyte counts, and reduced levels of myeloperoxidase and interleukin-1 beta (IL-1β) in the peritoneal exudate. The levels of IL-10, an anti-inflammatory cytokine, were enhanced by carvacryl acetate. Pretreatment with carvacryl acetate also decreased the number of acetic acid-induced writhing, increased the latency time of the animals on the hot plate and decreased paw licking time in the formalin, capsaicin and glutamate tests. The pretreatment with naloxone did not reverse the carvacryl acetate-mediated nociceptive effect.Significance
In conclusion, the current study demonstrated that carvacryl acetate exhibited anti-inflammatory activity in mice by reducing inflammatory mediators, neutrophil migration and cytokine concentration, and anti-nociceptive activity due to the involvement of capsaicin and glutamate pathways. 相似文献992.
Liana Dantas da Costa e Silva Laise Carla Lima Verde Rodrigues Viviane Ramos dos Santos Mariangela da Costa Allgayer Alexandre de Barros Falcão Ferraz Helena Campos Rolla Patrícia Pereira Jaqueline Nascimento Picada 《Life sciences》2014
Aim
Lobeline is a natural alkaloid derived from Lobelia inflata that has been investigated as a clinical candidate for the treatment of alcoholism. In a pre-clinical trial, lobeline decreased the preference for and consumption of ethanol, due to the modulation of the nicotinic acetylcholine receptor. However, the interaction between lobeline and ethanol is poorly known and thus there are safety concerns.The present study was conducted to evaluate the mutagenic and genotoxic effects of lobeline and assess its modulation of ethanol-induced toxicological effects.Main methods
CF-1 male mice were divided into five groups. Groups received an intraperitoneal injection of saline solution, lobeline (5 or 10 mg/kg), ethanol (2.5 g/kg), or lobeline plus ethanol, once a day for three consecutive days. Genotoxicity was evaluated in peripheral blood using the alkaline comet assay. The mutagenicity was evaluated using both Salmonella/microsome assay in TA1535, TA97a, TA98, TA100, and TA102 Salmonella typhimurium strains and the micronucleus test in bone marrow. Possible liver and kidney injuries were evaluated using biochemical analysis.Key findings
Lobeline did not show genotoxic or mutagenic effects and did not increase the ethanol-induced genotoxic effects in blood. Lobeline also protected blood cells against oxidative damage induced by hydrogen peroxide. Biochemical parameters were not altered, indicating no liver or kidney injuries or alterations in lipid and carbohydrate metabolisms.Significance
These findings suggest that lobeline does not induce gene or chromosomal mutations, and that this lack of genetic toxicity is maintained in the presence of ethanol, providing further evidence of the safety of this drug to treat alcohol dependence. 相似文献993.
Claudia Mendon?a Bezerra Luciano Pamplona de Góes Cavalcanti Rita de Cássia Moreira de Souza Silvia Ermelinda Barbosa Samanta Cristina das Chagas Xavier Ana Maria Jansen Relrison Dias Ramalho Liléia Diotaiut 《Memórias do Instituto Oswaldo Cruz》2014,109(7):887-898
The role played by different mammal species in the maintenance of Trypanosoma
cruzi is not constant and varies in time and place. This study aimed to
characterise the importance of domestic, wild and peridomestic hosts in the
transmission of T. cruzi in Tauá, state of Ceará, Caatinga area,
Brazil, with an emphasis on those environments colonised by Triatoma
brasiliensis. Direct parasitological examinations were performed on
insects and mammals, serologic tests were performed on household and outdoor mammals
and multiplex polymerase chain reaction was used on wild mammals. Cytochrome b was
used as a food source for wild insects. The serum prevalence in dogs was 38% (20/53),
while in pigs it was 6% (2/34). The percentages of the most abundantly infected wild
animals were as follows: Thrichomys laurentius 74% (83/112)
and Kerodon rupestris 10% (11/112). Of the 749 triatomines
collected in the household research, 49.3% (369/749) were positive for T.
brasiliensis, while 6.8% were infected with T. cruzi
(25/369). In captured animals, T. brasiliensis shares a
natural environment with T. laurentius, K.
rupestris, Didelphis albiventris, Monodelphis
domestica, Galea spixii, Wiedomys
pyrrhorhinos, Conepatus semistriatus and Mus
musculus. In animals identified via their food
source, T. brasiliensis shares a natural environment with
G. spixii, K. rupestris, Capra hircus, Gallus
gallus, Tropidurus oreadicus and Tupinambis merianae.
The high prevalence of T. cruzi in household and peridomiciliar
animals reinforces the narrow relationship between the enzootic cycle and humans in
environments with T. brasiliensis and characterises it as
ubiquitous. 相似文献
994.
Maurício Bianchini Moresco Alan da Silveira Fleck Maria Fernanda Hornos Carneiro Fernando Barbosa Júnior Sergio Luis Amantea Claudia Ramos Rhoden 《Biological trace element research》2014,161(2):161-166
Asthma is a multifactorial disease and its severity varies with the inflammatory status of the patient. It has been hypothesized that deficiency of trace elements has an important role in the etiology of asthma. The aim of the study was to evaluate the concentration of trace elements in nails of adolescents with different degrees of airway inflammation. We assessed the prevalence of active and severe asthma in adolescents (n?=?106) through the ISAAC questionnaire. Subjects were allocated into two different groups according to the value of fraction exhaled nitric oxide (FeNO) measured. Also, nail specimens were collected in order to determine the concentration of accumulated trace elements (Cu, Zn, Mn, Se) by ICP-MS. It was performed Student’s t test to evaluate statistical differences between inflammatory groups considering normally distributed data. On the other hand, when data presented non-normal distribution, Mann-Whitney U test was utilized. Spearman coefficients were calculated to investigate correlations between FeNO and mineral concentrations. Exhaled NO was increased in male subjects. We found association between active asthma and elevated exhaled NO. There was no significant difference in Cu (4.40 vs. 4.52), Zn (84.66 vs. 79.48), Mn (0.59 vs. 0.76), and Se (0.18 vs. 0.19) concentrations (μg/g) among distinct FeNO groups as well as was not observed correlation between exhaled NO levels and any element. Deficiency of trace elements in nails were not associated with increased FeNO. 相似文献
995.
Taciana Martins Barbosa Paula Braga Gomes Anne-Sophie Bergeron André Melo Santos Cristiano Chagas Erika M. S. Freitas Carlos Daniel Perez 《Hydrobiologia》2014,734(1):201-212
Soft corals show a wide variety of reproductive strategies, including both asexual and sexual reproduction which can influence macro-evolutionary processes. The octocoral Carijoa riisei has an ample geographical distribution in Pacific and southern Atlantic and also in Caribbean region. This species was considered invasive in Hawaii, and its capacity for rapid proliferation is recognized, but recent studies, however, have indicated that it appears to be native to the Indo-Pacific region. The present study examined the reproductive biology of C. riisei in the Atlantic basin. The results were then compared to previous studies of the same species from the Pacific (Hawaii) and Caribbean (Puerto Rico) regions to examine the hypothesis that the reproductive patterns of C. riisei populations are the same throughout its geographical distribution, independent of its native or non-native status. Samples were collected on a monthly basis from May/2007 to April/2008 at Porto de Galinhas (Pernambuco State, Brazil). This species was found to have similar reproduction patterns in Brazil, the Caribbean, and in Hawaii (a gonochoric reproductive pattern and continuous and asynchronous gamete release). The similarities of their traits contribute to its rapid proliferation and occupation of spaces left by other species, independent of its native or non-native status. 相似文献
996.
Edson Victor Euclides de Andrade Ivo Jael Lourenço Palhas Geraldo Jorge Barbosa de Moura 《Hydrobiologia》2014,723(1):181-194
Tadpoles are found in diverse aquatic habitats, where they share resources in various dimensions. Tadpole assemblages were studied in two temporary ponds in Atlantic Rainforest. Our aim was to analyze the temporal and spatial distribution patterns and their correlation with abiotic factors. Tadpoles were sampled weekly using nets, from March to December 2008. Samples were collected during the day and at night, and taken near the shore and in the centre of the ponds. Samples in inshore and pond centres were taken from both areas with and without aquatic vegetation. The assemblage consisted of 15 species in pond A and 12 species in pond B. The majority of species was accidental, and used the pond continuously. The assemblage was predominantly diurnal, which may be related to greater activity rate. In pond A the tadpoles primarily used the centre of ponds, whereas in pond B tadpoles primarily used shore areas. However, some populations showed preferences for particular environments. In pond A, environmental heterogeneity in the centre had the greatest influence on tadpole abundance. Our data suggest that temporal distribution facilitated the coexistence of different species of tadpoles in the pond but this conclusion is tentative and requires verification. Hence, more data needs to be collected so that we can propose effective area management plans. 相似文献
997.
Aline Teixeira Amorim Lucas Miranda Marques Angelita Maria Oliveira Gusm?o Santos Hellen Braga Martins Maysa Santos Barbosa Izadora Souza Rezende Ewerton Ferraz Andrade Guilherme Barreto Campos Tássia Neves Lob?o Beatriz Araujo Cortez Telma Alvez Monezi Glaucia Maria Machado-Santelli Jorge Timenetsky 《Biological research》2014,47(1)
Background
Bacterial pathogens have many strategies for infecting and persisting in host cells. Adhesion, invasion and intracellular life are important features in the biology of mollicutes. The intracellular location of Ureaplasma diversum may trigger disturbances in the host cell. This includes activation or inhibition of pro and anti-apoptotic factors, which facilitate the development of host damage. The aim of the present study was to associate U. diversum infection in HEp-2 cells and apoptosis induction. Cells were infected for 72hs with four U. diversum clinical isolates and an ATCC strain. The U. diversum invasion was analyzed by Confocal Laser Scanning Microscopy and gentamicin invasion assay. The apoptosis was evaluated using pro-apoptotic and anti-apoptotic gene expression, and FITC Annexin V/Dead Cell Apoptosis Kit.Results
The number of internalized ureaplasma in HEp-2 cells increased significantly throughout the infection. The flow cytometry analysis with fluorochromes to detect membrane depolarization and gene expression for caspase 2, 3 and 9 increased in infected cells after 24 hours. However, after 72 hours a considerable decrease of apoptotic cells was observed.Conclusions
The data suggests that apoptosis may be initially induced by some isolates in association with HEp-2 cells, but over time, there was no evidence of apoptosis in the presence of ureaplasma and HEp-2 cells. The initial increase and then decrease in apoptosis could be related to bacterial pathogen-associated molecular pattern (PAMPS). Moreover, the isolates of U. diversum presented differences in the studied parameters for apoptosis. It was also observed that the amount of microorganisms was not proportional to the induction of apoptosis in HEp-2 cells. 相似文献998.
999.
Maria J. Ferraz Wouter W. Kallemeijn Mina Mirzaian Daniela Herrera Moro Andre Marques Patrick Wisse Rolf G. Boot Lianne I. Willems H.S. Overkleeft J.M. Aerts 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2014,1841(5):811-825
Gaucher disease (GD) and Fabry disease (FD) are two relatively common inherited glycosphingolipidoses caused by deficiencies in the lysosomal glycosidases glucocerebrosidase and alpha-galactosidase A, respectively. For both diseases enzyme supplementation is presently used as therapy. Cells and tissues of GD and FD patients are uniformly deficient in enzyme activity, but the two diseases markedly differ in cell types showing lysosomal accumulation of the glycosphingolipid substrates glucosylceramide and globotriaosylceramide, respectively. The clinical manifestation of Gaucher disease and Fabry disease is consequently entirely different and the response to enzyme therapy is only impressive in the case of GD patients. This review compares both glycosphingolipid storage disorders with respect to similarities and differences. Presented is an update on insights regarding pathophysiological mechanisms as well as recently available biochemical markers and diagnostic tools for both disorders. Special attention is paid to sphingoid bases of the primary storage lipids in both diseases. The value of elevated glucosylsphingosine in Gaucher disease and globotriaosylsphingosine in Fabry disease for diagnosis and monitoring of disease is discussed as well as the possible contribution of the sphingoid bases to (patho)physiology. This article is part of a Special Issue entitled New Frontiers in Sphingolipid Biology. 相似文献
1000.
Carolina M. Koeller Hanke van der Wel Christa L. Feasley Fernanda Abreu Juliana Dutra Barbosa da Rocha Fabrício Montalv?o Patrícia Fampa Flávia C. G. dos Reis Georgia C. Atella Thaís Souto-Padrón Christopher M. West Norton Heise 《Eukaryotic cell》2014,13(10):1312-1327
All life cycle stages of the protozoan parasite Trypanosoma cruzi are enveloped by mucin-like glycoproteins which, despite major changes in their polypeptide cores, are extensively and similarly O-glycosylated. O-Glycan biosynthesis is initiated by the addition of αGlcNAc to Thr in a reaction catalyzed by Golgi UDP-GlcNAc:polypeptide O-α-N-acetyl-d-glucosaminyltransferases (ppαGlcNAcTs), which are encoded by TcOGNT1 and TcOGNT2. We now directly show that TcOGNT2 is associated with the Golgi apparatus of the epimastigote stage and is markedly downregulated in both differentiated metacyclic trypomastigotes (MCTs) and cell culture-derived trypomastigotes (TCTs). The significance of downregulation was examined by forced continued expression of TcOGNT2, which resulted in a substantial increase of TcOGNT2 protein levels but only modestly increased ppαGlcNAcT activity in extracts and altered cell surface glycosylation in TCTs. Constitutive TcOGNT2 overexpression had no discernible effect on proliferating epimastigotes but negatively affected production of both types of trypomastigotes. MCTs differentiated from epimastigotes at a low frequency, though they were apparently normal based on morphological and biochemical criteria. However, these MCTs exhibited an impaired ability to produce amastigotes and TCTs in cell culture monolayers, most likely due to a reduced infection frequency. Remarkably, inhibition of MCT production did not depend on TcOGNT2 catalytic activity, whereas TCT production was inhibited only by active TcOGNT2. These findings indicate that TcOGNT2 downregulation is important for proper differentiation of MCTs and functioning of TCTs and that TcOGNT2 regulates these functions by using both catalytic and noncatalytic mechanisms. 相似文献