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1.
Photodiagnosis Photodyn Ther ; 39: 103030, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35872352

RESUMO

More than half of the global population lives in areas where the Aedes aegypti mosquito is present. Efforts have been made to deal with the population of this mosquito in the larval and adult stages to prevent outbreaks of diseases (Dengue, Zika, Chikungunya, and Yellow Fever). In this scenario, photodynamic inactivation may be an effective alternative method to control this vector population. To evaluate the efficacy of the riboflavin - B2 vitamin - as photosensitizer (PS) in the photodynamic inactivation of Ae. aegypti larvae, different concentrations (0; 0.005; 0.010; 0.025; 0.050; 0.075 and 0.100 mg mL-1) were evaluated under white light from RGB LEDs at a light dose of 495.2  J cm-2. The results reveal that riboflavin can be successfully applied as a PS agent to photoinactivate Ae. aegypti larvae, showing its potential to deal with the larvae population.


Assuntos
Aedes , Fotoquimioterapia , Infecção por Zika virus , Zika virus , Aedes/fisiologia , Animais , Larva , Mosquitos Vetores , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Riboflavina/farmacologia
2.
J Photochem Photobiol B ; 224: 112323, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34598019

RESUMO

This work evaluated the photosensitizing activity of isomeric tetra-cationic porphyrins with peripheral [Pt(bpy)Cl]+ to control the larval population of Aedes aegypti by photodynamic action. The photolarvicidal activity of the tetra-platinated porphyrins at meta and para position (3-PtTPyP and 4-PtTPyP) was evaluated under blue (450 nm), green (525 nm), and red (625 nm) light illumination at 55.0 J cm-2. The meta isomer presented an efficient photolarvicidal activity even at a low concentration (1.2 ppm) in the presence of light, while the para counterpart was inactive regardless of the concentration and illumination. The different responses were related to the improved optical features and higher water solubility of 3-PtTPyP compared to 4-PtTPyP. Additionally, the potential environmental toxicity of 3-PtTPyP was tested in a plant model (Allium cepa test), with no toxicity detected for all used concentrations (1.2 to 12 ppm). Hence, this work reveals that 3-PtTPyP has a great potential to be employed to photodynamically control the insect vector population in an environmentally safe way.


Assuntos
Aedes/crescimento & desenvolvimento , Complexos de Coordenação/farmacologia , Larva/efeitos dos fármacos , Controle de Mosquitos/métodos , Fármacos Fotossensibilizantes/farmacologia , Compostos de Platina/química , Porfirinas/química , Animais , Complexos de Coordenação/química , Isomerismo
3.
ARS Vet, v. 37, n. 2, 067-073, jun. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4879

RESUMO

Little is known about the toxicity of immune modulators in fish. Zafirlukast is an anti-inflammatory that antagonizes cysteine leukotriene receptors (CysLTR1). Aiming to study immunomodulatory treatments on fish health, this study evaluated the clinical safety of oral zafirlukast treatment, through biochemical and hematological analyzes during acute inflammatory reaction in Nile tilapia (Oreochromis niloticus), induced by Aeromonas hydrophilabacterins. 72 young tilapias were randomly divided in 9 aquariums (100 L each, n=8) to compose the following treatments: T0 (control), T1 (Treatment with 250 μg zafirlukast) and T2 (Treatment with 500 μg zafirlukast). Eight animals were evaluated per treatment in three periods: six, 24 and 48 hours post-inoculation (HPI), blood collection was performed for hematological and serum biochemical evaluation. The study of hepatic and renal functionality revealed that treatment with both doses of zafirlukast did not result in changes in the circulating values of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, creatinine, triglycerides, cholesterol, and total protein, suggesting that the drug has not presented hepatotoxicity, as well as compromised liver and kidney functions. Tilapia submitted to treatment with 500 μg showed adverse hematological effects characterizedby polycythemia associated with microcytosis. Therefore, oral treatment with zafirlukast has demonstrated clinical safety at a therapeutic dose of 250 μg in tilapia during acute aerocystitis, although hematological changes were observed in tilapia treatedwith overdose of this leukotriene blocker.


Pouco se sabe sobre a toxicidade de imunomoduladores em peixes. Zafirlukast é um anti-inflamatório que antagoniza os receptores de leucotrienos cisteínicos (CysLTR1). Com o objetivo de estudar o efeito de tratamentos imunomoduladores sobre a saúde dos peixes, este estudo avaliou a segurança clínica do tratamento com zafirlucaste oral, por meio de análises bioquímicas e hematológicas durante reação inflamatória aguda em tilápia do Nilo (Oreochromis niloticus), induzida por bacterinas de Aeromonas hydrophila.Para tal, 72 tilápias jovens foram divididas aleatoriamente em 9 aquários (100 L cada, n=8) para compor os seguintes tratamentos: T0 (controle), T1 (Tratamento com 250 μg de zafirlucaste) e T2 (Tratamento com 500 μg de zafirlucaste). Oito animais foram avaliados por tratamento em três períodos: seis, 24 e 48 horas pós-inoculação (HPI), foi realizada coleta de sangue para avaliação hematológica e bioquímica sérica. O estudo da funcionalidade hepática e renal revelou que o tratamento com ambas as doses de zafirlucaste não resultou em alterações nos valores circulantes de aspartato aminotransferase (AST), alanina aminotransferase (ALT), fosfatase alcalina, creatinina, triglicerídeos, colesterol e proteína total, sugerindo que a droga não comprometeu as funçõeshepáticas e renais. As tilápias tratadas com 500 μg apresentaram efeitos hematológicos adversos caracterizados por policitemia associada a microcitose. Portanto, o tratamento oral com zafirlucaste demonstrou segurança clínica nadose de 250 μg em tilápiasdurante aerocistite aguda, embora alterações hematológicas tenham sido observadas em tilápias tratadas com sobredosagem deste bloqueador de leucotrieno.

4.
Neurobiol Learn Mem ; 160: 91-97, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29614375

RESUMO

Sleep deprivation is known to affect memory formation, but how it interacts with different memory systems is not completely understood. Adenosine, a homeostatic regulator of sleep that has an increased extracellular concentration during sleep deprivation, is one of the neuromodulators that may be involved in this interaction. The A1 adenosine receptor is involved in both sleep regulation and memory formation. Among other pathways, the A1 receptor decreases cAMP levels in the cytosol and thus also regulates protein kinase A (PKA) and exchange protein activated by cAMP (EPAC) activity. To verify the role of the A1 receptor in the memory impairment caused by sleep deprivation, we tested the effect of 96 h of sleep deprivation (SD) and the administration of DPCPX, an A1 receptor antagonist on male Wistar rats prior to the training sessions for two memory tasks that relies on the hippocampal function: the multiple trial inhibitory avoidance (MTIA) task, which also requires the striatum, and the contextual fear conditioning (CFC) task, which does not. We also evaluated the effect of SD, DPCPX and the MTIA training session on the protein expression levels of the A1 receptor, PKA phosphorylation and EPAC activity in both the hippocampus and the striatum. Sleep deprivation impaired the performance in the test sessions of both tasks; DPCPX was able to prevent the impairment in the MTIA test but not in the CFC test. SD increased A1 receptor protein expression levels in the striatum but not in the hippocampus and also decreased PKA phosphorylation in both structures; DPCPX prevented this decrease in the striatum, but not in the hippocampus. Finally, SD had no effect on EPAC activity in either of the structures. These results indicate that the A1 adenosine receptors play a role in the memory impairment caused by sleep deprivation in tasks that involve the striatum through modulation of the cAMP/PKA pathway.


Assuntos
Adenosina/metabolismo , Aprendizagem da Esquiva/fisiologia , Condicionamento Clássico/fisiologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Hipocampo , Transtornos da Memória , Receptor A1 de Adenosina/metabolismo , Privação do Sono , Antagonistas do Receptor A1 de Adenosina/farmacologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Condicionamento Clássico/efeitos dos fármacos , Regulação para Baixo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Masculino , Transtornos da Memória/metabolismo , Transtornos da Memória/fisiopatologia , Ratos , Ratos Wistar , Receptor A1 de Adenosina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Privação do Sono/metabolismo , Privação do Sono/fisiopatologia , Xantinas/farmacologia
5.
Behav Brain Res ; 331: 20-24, 2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28506620

RESUMO

Sleep deprivation impairs performance in emotional memory tasks, however this effect on memory is not completely understood. Possible mechanisms may involve an alteration in neurotransmission systems, as shown by the fact that many drugs that modulate neural pathways can prevent memory impairment by sleep loss. Gastrin releasing peptide (GRP) is a neuropeptide that emerged as a regulatory molecule of emotional memory through the modulation of other neurotransmission systems. Thus, the present study addressed the effect of intraperitoneal (IP) administration of bombesin (BB) (2.5, 5.0 and 10.0µg/kg), a GRP agonist, on the performance of Wistar rats in a multiple trail inhibitory avoidance (MTIA) task, after sleep deprivation, using the modified multiple platforms method (MMPM). Sleep deprived animals exhibited acquisition and retention impairment that was not prevented by BB injection. In addition, non-sleep deprived animals treated with BB before and after the training session, but not before the test, have shown a retention deficit. In summary, BB did not improve the memory impairment by sleep loss and, under normal conditions, produced a memory consolidation deficit.


Assuntos
Bombesina/farmacologia , Transtornos da Memória/induzido quimicamente , Memória/efeitos dos fármacos , Privação do Sono , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Fragmentos de Peptídeos/farmacologia , Ratos Wistar , Privação do Sono/tratamento farmacológico
6.
Artigo em Inglês | MEDLINE | ID: mdl-27280858

RESUMO

The interaction between chlorophyll (Chl) and silver nanoparticles (AgNPs) was evaluated by analyzing the optical behavior of Chl molecules surrounded by different concentrations of AgNPs (10, 60, and 100nm of diameter). UV-Vis absorption, steady state and time-resolved fluorescence measurements were performed for Chl in the presence and absence of these nanoparticles. AgNPs strongly suppressed the Chl fluorescence intensity at 678nm. The Stern-Volmer constant (KSV) showed that fluorescence suppression is driven by the dynamic quenching process. In particular, KSV was nanoparticle size-dependent with an exponential decrease as a function of the nanoparticle diameter. Finally, changes in the Chl fluorescence lifetime in the presence of nanoparticles demonstrated that the fluorescence quenching may be induced by the excited electron transfer from the Chl molecules to the metal nanoparticles.

8.
J Fluoresc ; 22(4): 1177-82, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22538833

RESUMO

In this work fluorescence-based method to assess the biodiesel production from different refined vegetable oils is presented. Four different refined oils (soybean, sunflower, canola, and corn) and their respective biodiesel were used and the fluorescence of the compounds contained in their compositions was taken as a probe. The results show that the fluorescence intensity of the biodiesel is lower than one verified in the vegetable oil. The data achieved point out that the ratio between the fluorescence intensity of biodiesel and oil is about 0.6 regardless of the vegetable oil feedstock investigated. Reduced content of fluorophores as well as low viscosity of the biodiesel regarding the oil have been raised as hypotheses to explain the low fluorescence intensity of the biodiesel. The results obtained may provide the basis for the development of an alternative method able to give fast and accurate information about the conversion of oil into biodiesel without the requirement of dilution or pre-treatment of the biodiesel.


Assuntos
Biocombustíveis , Óleos de Plantas/química , Espectrometria de Fluorescência/métodos , Fluorescência , Glicerol/química
9.
J Fluoresc ; 20(3): 645-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20145983

RESUMO

Two soybean cultivars, one conventional and a glyphosate-tolerant (transgenic), were submitted to the water stress and the chlorophyll a fluorescence induced by UV light was monitored daily during 16 days. In this work, 40 pots in total, 20 per cultivar were used in the investigation. Each cultivar was divided in two groups, the control group and the group submitted to the water stress. The stress response of the cultivars was monitored by red to far-red fluorescence ratio. The data indicate that the water stress induced the earliest changes on the fluorescence ratio and chlorophyll content for the conventional cultivar. In addition, a comparative analysis of the fluorescence ratios of the cultivars reveals that conventional plants have higher chlorophyll content than transgenic ones. This result might be useful in the development of methodologies able to distinguish conventional to transgenic apart.


Assuntos
Fluorescência , Glycine max/genética , Plantas Geneticamente Modificadas/genética , Água/análise , Água/metabolismo , Clorofila , Clorofila A , Desidratação/genética
10.
Appl Opt ; 48(30): 5728-32, 2009 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-19844308

RESUMO

Thermal lens (TL) spectrometry was applied to soybean biodiesel samples, in order to assess the behavior of their thermo-optical properties during the preparation before and after the washing process. The study was based on the thermal diffusivity parameter, which is highly sensitive and is related to the chemical composition of the sample. The results showed a difference of approximately 20% between the initial (unwashed) and the final (washed) steps of biodiesel production. This behavior indicates that the residue of the biodiesel production influences the thermal diffusivity value. Consequently, TL spectrometry can be a useful methodology for certifying the quality of biodiesel during production.


Assuntos
Antioxidantes/química , Fontes de Energia Bioelétrica , Difusão , Desenho de Equipamento , Etanol/química , Temperatura Alta , Metanol/química , Óptica e Fotônica , Óleo de Soja/química , Glycine max , Espectrofotometria/métodos
11.
Inorg Chem ; 47(2): 690-8, 2008 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-18081273

RESUMO

The bonding properties of cations in phosphate glasses determine many short- and medium-range structural features in the glass network, hence influencing bulk properties. In this work, Pb-Al-metaphosphate glasses (1 - x)Pb(PO(3))(2).xAI(PO(3))(3) with 0 < or = x < or = 1 were analyzed to determine the effect of the substitution of Pb by AI on the glass structure in the metaphosphate composition. The glass transition temperature and density were measured as a function of the Al concentration. The vibrational and structural properties were probed by Raman spectroscopy and nuclear magnetic resonance of (31)P, (27)AI, and (207)Pb. Aluminum incorporates homogeneously in the glass creating a stiffer and less packed network. The average coordination number for AI decreases from 5.9 to 5.0 as x increases from 0.1 to 1, indicating more covalent AI-O bonds. The coordination number of Pb in these glasses is greater than 8, showing an increasing ionic behavior for compositions richer in AI. A quantitative analysis of the phosphate speciation shows definite trends in the bonding of AIO(n) groups and phosphate tetrahedra. In glasses with x < 0.48, phosphate groups share preferentially only one nonbridging O corner with an AIO(n) coordination polyhedron. For x > 0.48 more than one nonbridging O can be linked to AIO(n) polyhedra. There is no corner sharing of O between AIO(n) and PbO(n) polyhedra nor between AIO(n) themselves throughout the compositional range. The PbO(n) coordination polyhedra show considerable nonbridging O sharing, with each O participating in the coordination sphere of at least two Pb. The bonding preferences determined for Al are consistent with the behavior observed in Na-AI and Ca-AI metaphosphates, indicating this may be a general behavior for ternary phosphate glasses.

12.
J. venom. anim. toxins incl. trop. dis ; 13(3): 620-639, 2007. graf
Artigo em Inglês | LILACS, VETINDEX | ID: lil-461648

RESUMO

Mice genetically selected for high (H) and low (L) antibody production (Selection IV-A) were used as murine experimental model. The aim of the present work was to evaluate the macrophagic activity and to characterize the immune response in Mycobacterium bovis-AN5 infected mice (3X107 bacteria). The response profile previously observed in such strains was not similar to that obtained during M. bovis infection; however, it corroborated works carried out using Selection I, which is very similar to Selection IV-A regarding infection by M. tuberculosis and Bacillus Calmette-Guérin (BCG). Considering bacterial recovery, LIV-A mice showed higher control of the infectious process in the lungs than in the spleen, whereas HIV-A mice presented more resistance in the spleen. With respect to macrophagic activity, hydrogen peroxide (H2O2) was probably not involved in the infection control since there was an inhibition in the production of this metabolite. Nitric oxide (NO) and TNF-a production seemed to be important in the control of bacterial replication and varied according to the strain, period and organ. Evaluation of the antibody production indicated that the multi-specific effect commonly observed in these strains was not the same in the response to M. bovis. Antibody concentrations were higher in LIV-A than in HIV-A mice at the beginning of the infection, being similar afterwards. Such data were compared with delayed-type hypersensitivity (DTH), which was more intense in HIV-A than in LIV-A mice, indicating that antibody production is independent of the capability to trigger DTH reactions and that cellular and humoral responses to M. bovis antigens show a polygenic control and an independent quantitative genetic regulation. Differences were observed among organs and metabolites, suggesting that different mechanisms play an important role in this infection in natural heterogeneous populations, indicating that NO, TNF-a and Th1 cytokines are involved in the infection control.(AU)


Assuntos
Animais , Camundongos , Imunidade , Formação de Anticorpos , Mycobacterium bovis , Peróxido de Hidrogênio
13.
Med Mycol ; 44(6): 505-14, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16966167

RESUMO

Mice genetically selected for high (H) and low (L) antibody production (HIV-A and LIV-A) were used in an experimental model of paracoccidioidomycosis. In a previous work, it was observed that male HIV-A animals were more susceptible to the infection due to adrenal gland damage. Male HIV-A and LIV-A animals were intravenously inoculated with Paracoccidioides brasiliensis (strain 18) and sacrificed 2, 4, 6, 8 and 10 weeks after inoculation. At each time interval, lungs and adrenals were removed to estimate recoverability of the fungus, as well as to determine Th1 (IFN-gamma, TNF-alpha) and Th2 (IL-4 and IL-10) cytokine profiles. While viable fungi recoverability from the lungs of HIV-A mice was higher after 4 and 8 weeks, there was less fungal recovery from the adrenals of LIV-A animals after the 2nd week, with total fungal elimination after the 8th week. With regard to Th2 cytokines, there was an inhibition in IL-4 production in the organs from infected animals, the extent of which varied according to the organ and the time period after initiation of infection. IL-10 production was found to be lower in both organs. Determination of Th1 cytokines revealed that IFN-gamma production increased in both organs, mainly in the adrenal of LIV-A after 8 and 10 weeks, when these animals showed a total fungal elimination. A significant difference was observed between HIV-A and LIV-A concerning TNF-alpha production in both organs and at all recovery times, in that LIV-A produced a higher level of this cytokine, mainly in the adrenal. These results may explain the high susceptibility of HIV-A to P. brasiliensis infection, is due, at least in part, to adrenal involvement. The higher production of Th1 cytokines by LIV-A in comparison to HIV-A mice may account for LIV-A resistance to P. brasiliensis infection. Our data reveal the importance of this experimental model in the study of the adrenal involvement in paracoccidioidomycosis, since this gland may be highly compromised in the patients, leading to the development of Addison's Disease.


Assuntos
Glândulas Suprarrenais/metabolismo , Citocinas/biossíntese , Pulmão/metabolismo , Paracoccidioides , Paracoccidioidomicose/imunologia , Células Th1/imunologia , Animais , Anticorpos Antifúngicos/biossíntese , Citocinas/análise , Masculino , Camundongos , Camundongos Endogâmicos , Células Th1/metabolismo , Células Th2/imunologia
14.
J. venom. anim. toxins incl. trop. dis ; 11(2): 198-212, May-Aug. 2005. tab, graf
Artigo em Inglês | LILACS | ID: lil-402364

RESUMO

Immune response to leptospirosis is mainly humorally mediated, and involves opsonization of leptospires for phagocytosis by macrophages and neutrophils. However, some aspects are still unknown. For a more detailed analysis of the cellular immune response to leptospirosis infection, trials were carried out in order to determine the hydrogen peroxide and nitric oxide (H2O2 and NO)production stimulated or not by Interferon-gamma. The participation of some specific cytokines, such as Tumor Necrosis Factor-alfa (TNF-alfa); Interferon-gamma (IFN-y); Interleukin-6 (IL-6); and Interleukin-4 (IL-4), in the immunopathology of this infection was also investigated. For this purpose, we analyzed the supernatant from peritonealmacrophage cell culture and the splenic cells of mice genetically selected as High (H) and Low (L) antibody producers, and inbred Balb/c mice infected with Leptospira interrogans serovar icterohaemorrhagiae. The IL-6 production varied from release speaks to inhibition in H, L, and Balb/c mice. The three strains presented constant and elevated production of TNF-alfa until day 14, suggesting its effective participation in the initial phase of the infection. Meanwhile, all the three strains presented a constant and irregular IFN-y production, with release peaks between the 7th and 14th days in L mice. The H and Balb/c mice strains presented a higher tendency to Th2 response pattern, whereas L mice tendend towards Th1 response


Assuntos
Animais , Masculino , Feminino , Citocinas , Imunidade Celular , Leptospirose/fisiopatologia , Leptospirose/imunologia , Camundongos , Fator de Necrose Tumoral alfa
15.
Inorg Chem ; 44(2): 423-30, 2005 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-15651890

RESUMO

Comprehension of short- and medium-range order of phosphate glasses is a topic of interest, due to the close relation between network structure and mechanical, thermal, and optical properties. In this work, the short-range structure of glasses (1 - x)Ca(PO(3))(2).xAl(PO(3))(3) with 0 < or = x < or = 0.47 was studied using solid-state nuclear magnetic resonance spectroscopy, Raman spectroscopy, density measurements, and differential scanning calorimetry. The bonding between a network modifier species, Al, and the network forming phosphate groups was probed using high-resolution nuclear magnetic resonance spectroscopy of (27)Al and (31)P. Changes in the compositional behavior of the density, glass transition temperature, PO(2) symmetric vibrations, and Al coordination number were verified at around x = 0.30. (31)P NMR spectra show the presence of phosphorus in Q(2) sites with nonbridging oxygens (NBOs) coordinated by Ca ions and also Q(2) sites with one NBO coordinated by Al (namely, Q(2)(1Al)). The changes in the properties as a function of x can be understood by considering the mean coordination number measured for Al and the formation of only Q(2) and Q(2)(1Al) species. It is possible to calculate that a network formed only by Q(2)(1Al) phosphates can just exist up to the upper limit of x = 0.48. Above this value, Q(2)(2Al) species should appear, imposing a major reorganization of the network. Above x = 0.30 the network undergoes a progressive reorganization to incorporate Al ions, maintaining the condition that only Q(2)(1Al) species are formed. These observations support the idea that bonding principles for cationic species inferred originally in binary phosphate glasses can also be extended to ternary systems.

16.
Br J Nutr ; 89(1): 89-96, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12568668

RESUMO

Chronic energy restriction, alpha-tocopherol supplementation and their interaction with exhaustive exercise were investigated. Eleven-week-old male Wistar rats (n 6x 10) were fed either a control (C), a 30 % carbohydrate-energy-restricted control (R) or an alpha-tocopherol-supplemented (S) diet for 5 months. The animals in each diet were divided into exercised (E) and non-exercised (NE) groups. Before killing, the exercised rats were required to run to exhaustion (39 (se 6), 69 (se 11) and 18 (se 2) min for the C, R and S groups, respectively). Lipid peroxidation (thiobarbituric acid-reactive substances; TBARS), protein damage (reactive carbonyls) and alpha-tocopherol were determined in gastrocnemius, liver, brain and/or plasma. There was no difference in lipid peroxidation between the R and C groups, but in liver and muscle peroxidation appeared significantly lower in the S than the other two diets. TBARS in the brain were similar in all groups. On the other hand, reactive carbonyls showed that both the R and S diets reduced protein damage in the brain, while exhaustive exercise increased it. For liver and muscle, however, reactive carbonyl levels were similar in all groups. alpha-Tocopherol supplementation increased the vitamin concentrations in liver, muscle and plasma, but exercise decreased them in plasma and brain. Carbohydrate-energy restriction increased (P=0.0025) resistance to exhaustive exercise considerably without depleting stores of alpha-tocopherol or exacerbating oxidative damage in monitored tissues. It is concluded that while exhaustive exercise promotes a tissue-specific oxidative damage detectable only in brain proteins, both experimental diets tended to ameliorate this condition.


Assuntos
Encéfalo/metabolismo , Carboidratos da Dieta/administração & dosagem , Ingestão de Energia/fisiologia , Estresse Oxidativo/fisiologia , Condicionamento Físico Animal/fisiologia , Animais , Peso Corporal/fisiologia , Dieta , Suplementos Nutricionais , Peroxidação de Lipídeos/fisiologia , Fígado/metabolismo , Masculino , Músculo Esquelético/metabolismo , Oxirredução , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Ratos , Ratos Wistar , alfa-Tocoferol/sangue , alfa-Tocoferol/farmacologia
17.
Med Mycol ; 38(4): 309-15, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10975699

RESUMO

High (H) and low (L) responder mice were selected for their ability to produce antibodies against sheep and human erythrocytes (Selection IV-A). In this selection, the difference in antibody responsiveness between H and L lines (HIV-A and LIV-A mice, respectively) was shown to depend mainly on macrophage function. The more rapid catabolism of antigens by macrophages in L mice has been suggested as the main cause of the low antibody production. Due to this high macrophage activity, L animals have been described as more resistant than H animals to intracellular pathogens. These animals were utilized as an experimental model of paracoccidioidomycosis. HIV-A and LIV-A mice were infected with Paracoccidioides brasiliensis by the intravenous route. As expected, H mice were more susceptible to P. brasiliensis with a shorter survival time and higher levels of specific antibodies when compared to L mice. Contrasting with the survival time, the lungs, spleen and liver from H mice showed typical nodular granulomas containing epithelioid and giant cells and few fungi. On the other hand, in LIV-A mice, the lesions of these organs were characterized by looser granulomas with irregular borders and the presence of a large number of fungi. However, the adrenal gland showed different lesion patterns. In H mice these lesions were extensive and characterized by loose granulomas with numerous fungi, while in LIV-A mice the lesions were small and limited to the cortex. Moreover the HIV-A mice presented higher levels of serum corticosterone when compared to LIV-A ones. The higher susceptibility of H mice could be attributed to the extensive lesions of the adrenal glands. These results suggest the use of the H line from the IV-A Selection as an experimental model for further studies of adrenal involvement in paracoccidioidomycosis.


Assuntos
Paracoccidioidomicose/imunologia , Glândulas Suprarrenais/patologia , Animais , Anticorpos Antifúngicos/sangue , Especificidade de Anticorpos , Corticosterona/sangue , Modelos Animais de Doenças , Suscetibilidade a Doenças , Fígado/patologia , Pulmão/patologia , Masculino , Camundongos , Paracoccidioidomicose/mortalidade , Paracoccidioidomicose/patologia
18.
J. venom. anim. toxins ; 6(2): 205-19, 2000. graf
Artigo em Inglês | LILACS | ID: lil-276609

RESUMO

Propolis has been the subject of several recent studies, with the aim of elucidating its biological and pharmacological properties. Propolis has a well-known antimicrobial activity as well as antioxidant, antitumoral, antiinflammatory, and regenerative properties, but literature about its effects on the immunes response in scarce. The goal of this work was to evaluate the propolis effect on macrophage activation by oxygen (H2O2) and nitrogen (NO) metabolite determination. Propolis was produced by africanized honeybees and hydroalcoholic solutions were prepared at different concentrations. Peritoneal macrophages were obtained from male BALB/c mice and culture cells were stimulated in vitro with propolis or interferon-gamma (IFN-gamma). In the in vivo assay, the animals were sacrificed after propolis treatment and cells were stimulated with IFN-gamma. We also investigated the co-stimulant action of propolis associated with IFN-gamma on macrophages. The results show that propolis induces a discreet elevation in H2O2 release and a mild inhibition of NO generation, depending on concentration. Propolis had no co-stimulant activity, diminishing IFN-gamma action on H2O2 and NO production. Data suggest that propolis acts on host non-specific immunity by macrophage activation.


Assuntos
Animais , Masculino , Ratos , Ativação de Macrófagos , Nitrogênio/metabolismo , Oxigênio/metabolismo , Peróxido de Hidrogênio/metabolismo , Própole/farmacologia , Abelhas , Interferon gama/metabolismo , Macrófagos Peritoneais
19.
Rev Soc Bras Med Trop ; 32(3): 229-34, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10380560

RESUMO

Leishmaniasis is a typical parasite infection whose protective immunity depends on macrophage activation. Susceptibility to Leishmania donovani infection was compared in H (high antibody responder) and L (low antibody responder) mice from selection IV-A. H mice infected intravenously with 10(7) amastigotes of L. donovani were more susceptible to infection than their L counterparts. This higher susceptibility was characterized by a higher splenic and hepatic parasite burden. An increased splenic index was observed in both lines after sixty days of infection. This splenomegaly was caused, at least partially, by an increase in the number of splenic cells as determined by direct counts of cells from spleen. The results show that selection IV-A is susceptible to visceral leishmaniasis, with the H line being more susceptible than the L line.


Assuntos
Leishmaniose Visceral/fisiopatologia , Animais , Anticorpos Antiprotozoários/biossíntese , Suscetibilidade a Doenças , Leishmania donovani , Masculino , Camundongos
20.
Mycopathologia ; 121(1): 1-5, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8437613

RESUMO

The antibody response against the antigen sheep red blood cells (SRBC) was investigated in mice pre-treated with formalin-killed Paracoccidioides brasiliensis or with cell wall fractions of the fungus. Pre-treatment with P. brasiliensis, as well as with the Fl fraction and beta-glucan significantly increased the anti-SRBC antibody response in the experimental groups as compared to the control group that received only SRBC. This immunomodulatory effect varied with the different doses employed and with pre-treatment time. We conclude that the cell wall fractions of P. brasiliensis might play an important role in the hypergammaglobulinemia associated with Paracoccidioidomycosis.


Assuntos
Hipergamaglobulinemia/microbiologia , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Animais , Formação de Anticorpos/fisiologia , Parede Celular/imunologia , Eritrócitos/imunologia , Hipergamaglobulinemia/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ovinos/imunologia
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