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Conhecimento, experiência e formação: do médico ao professor de medicina. Estudo sobre a disciplina formação didático-pedagógica em Saúde nos cursos de Pós-graduação da Universidade Federal de Säo Paulo
(Universidade Federal de São Paulo (UNIFESP), 1997) Batista, Nildo Alves [UNIFESP]
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A fat-enriched, glucose-enriched diet markedly attenuates adiponectin mRNA levels in rat epididymal adipose tissue
(Portland Press, 2003-10-01) Naderali, E. K.; Estadella, Debora [UNIFESP]; Rocha, M.; Pickavance, L. C.; Fatani, S.; Denis, RGP; Williams, G.; Univ Liverpool; Universidade Federal de São Paulo (UNIFESP); Univ Complutense
Adiponectin levels are decreased in subjects with obesity, diabetes and coronary artery disease. in the present study, we have investigated whether the decrease in the levels and mRNA expression of adiponectin is due to obesity or to the diet itself. Wistar rats were either fed standard laboratory chow throughout (controls) or given a fat-enriched, glucose-enriched diet (diet-fed) for 2 days or 16 weeks. After 2 days of diet feeding, total body weight, fat pad masses and the plasma levels of glucose, insulin and leptin were all comparable between the two groups, while plasma NEFA (non-esterified fatty acid) and triacylglycerol levels were increased in the diet-fed animals (P < 0.01 for both). There was a marked (P < 0.01) decrease in plasma adiponectin levels. After 16 weeks of diet feeding, diet-fed rats had significantly higher body weight, fat pad mass and plasma levels of leptin, adiponectin, NEFA and triacylglycerol (P < 0.001 for all) compared with chow-fed controls, whereas plasma levels of glucose and insulin were similar in the two groups. After 2 days of diet feeding, there were no significant changes in Ob mRNA levels in epididymal fat, whereas there was a marked decrease in adiponectin mRNA levels. After 16 weeks of diet feeding, rats had significantly increased levels of Ob mRNA, but decreased adiponectin mRNA levels, in epididymal fat compared with the chow-fed group (P < 0.001 for both). These findings suggest that obesity per se is not a factor in the decreased adiponectin levels observed in obese subjects. We propose that the lipid profile of the plasma and/or the constituents of the diet consumed by rats may contribute to adiponectin levels more than obesity per se.
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Protective immunity against Trypanosoma cruzi infection in a highly susceptible mouse strain after vaccination with genes encoding the amastigote surface protein-2 and trans-sialidase
(Mary Ann Liebert Inc Publ, 2004-09-01) Vasconcelos, Jose Ronnie Carvalho de [UNIFESP]; Hiyane, Meire Ioshie [UNIFESP]; Marinho, Claudio Romero Farias; Claser, Carla [UNIFESP]; Machado, Alexandre de Magalhaes Vieira; Gazzinelli, Ricardo Tostes; Bruna-Romero, Oscar; Alvarez, Jose Maria; Boscardin, Silvia Beatriz [UNIFESP]; Rodrigues, Mauricio Martins [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP); Universidade Federal de Minas Gerais (UFMG); Fiocruz MS
Protective immunity against lethal infection is developed when BALB/c or C57BL/6 mice are immunized with plasmids containing genes from the protozoan parasite Trypanosoma cruzi. However, genetic vaccination of the highly susceptible mouse strain A/Sn promoted limited survival after challenge. This observation questioned whether this type of vaccination would be appropriate for highly susceptible individuals. Here, we compared the protective efficacy and the immune response after individual or combined genetic vaccination of A/Sn mice with genes encoding trans-sialidase (TS) or the amastigote surface protein-2 (ASP-2). After challenge, a significant proportion of A/Sn mice immunized with either the asp-2 gene or simultaneously with asp-2 and ts genes, survived infection. in contrast, the vast majority of mice immunized with the ts gene or the vector alone died. Parasitological and histological studies performed in the surviving mice revealed that these mice harbored parasites; however, minimal inflammatory responses were seen in heart and striated muscle. We used this model to search for an in vitro correlation for protection. We found that protective immunity correlated with a higher secretion of interferon-gamma by spleen cells on in vitro restimulation with ASP-2 and the presence of ASP-2-specific CD8 cells. Depletion of either CD4 or CD8 or both T-cell subpopulations prior to the challenge rendered the mice susceptible to infection demonstrating the critical contribution of both cell types in protective immunity. Our results reinforce the prophylactic potential of genetic vaccination with asp-2 and ts genes by describing protective immunity against lethal T. cruzi infection and chronic tissue pathology in a highly susceptible mouse strain.
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Spatial and temporal profiles for anti-inflammatory gene expression in leukocytes during a resolving model of peritonitis
(Amer Assoc Immunologists, 2006-04-01) Damazo, Amilcar S. [UNIFESP]; Yona, Simon; Flower, Roderick J.; Perretti, Mauro; Oliani, Sonia M. [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Barts & London Queen Mary Sch Med & Dent
The recent appreciation of the role played by endogenous counterregulatory mechanisms in controlling the outcome of the host inflammatory response requires specific analysis of their spatial and temporal profiles. In this study, we have focused on the glucocorticoid-regulated anti-inflammatory mediator annexin 1. Induction of peritonitis in wild-type mice rapidly (4 h) produced the expected signs of inflammation, including marked activation of resident cells (e.g., mast cells), migration of blood-borne leukocytes, mirrored by blood neutrophilia. These changes subsided after 48-96 h. In annexin 1(null) mice, the peritonitis response was exaggerated (similar to 40% at 4 h), with increased granulocyte migration and cytokine production. In blood leukocytes, annexin I gene expression was activated at 4, but not 24, h postzymosan, whereas protein levels were increased at both time points. Locally, endothelial and mast cell annexin I gene expression was not detectable in basal conditions, whereas it was switched on during the inflammatory response. The significance of annexin 1 system plasticity in the anti-inflammatory properties of dexamethasone was assessed. Clear induction of annexin 1 gene in response to dexamethasone. treatment was evident in the circulating and migrated leukocytes, and in connective tissue mast cells; this was associated with the steroid failure to inhibit leukocyte trafficking, cytokine synthesis, and mast cell degranulation in the annexin 1(null) mouse. In conclusion, understanding how inflammation is brought under control will help clarify the complex interplay between pro- and anti-inflammatory pathways operating during the host response to injury and infection.
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Stress and cardiac beta adrenoceptors
(Taylor & Francis Ltd, 2006-06-01) Santos, Iraides N.; Spadari-Bratfisch, Regina Celia [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade Estadual de Campinas (UNICAMP)
Most modern theories about stress recognize that although stress is not a disease, it may be the trigger for the majority of diseases when allostatic overload has been generated. During stress, the glucocorticoids and catecholamines play a key role in the regulation of physiological parameters and homeostasis during stress. in the heart, positive chronotropic, inotropic, and lusitropic responses to catecholamines are mediated by various subtypes of adrenergic receptors (beta-ARs), mainly beta(1)- and beta(2)-adrenergic receptors. beta-ARs also control cardiomyocyte growth and death, thus contributing to cardiac remodelling. the structural basis of each beta-AR subtype, as well as their signalling pathways, and adaptive responses to stress are discussed. the participation of beta(3)- and putative beta(4)- ARs in the control of cardiac function is also discussed, with emphasis on low affinity beta-AR isoforms and the role they play in the response to the catecholamines under stress. the changes in beta-AR signalling under pathogenic conditions as well as under stress are reviewed.
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Changes in the pro-inflammatory cytokine production and peritoneal macrophage function in rats with chronic heart failure
(Elsevier B.V., 2006-06-01) Batista, M. L.; Santos, Ronaldo Vagner Thomatieli dos [UNIFESP]; Cunha, L. M.; Mattos, K.; Oliveira, E. M.; Seelaender, M. C. L.; Rosa, L. F. B. P. Costa; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)
Chronic heart failure (CHF) is a state of immune activation, and pro-inflammatory cytokines play an important role in its development and progression. Macrophages (M phi s), when activated, are the main source of pro-inflammatory cytokines. We measured interjeukin-6 (IL-6), interleukin (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) production after lipopolysaccharide (LPS)-stimulation, as well as peritoneal M phi s migration, phagocytic capacity, chemotaxis index, and hydrogen peroxide production, in an attempt to clarify the role of this cell in an animal model of CHF. Ligature of the left coronary artery or sham operation was performed in adult Wistar rats. After 12 weeks, resident and total cell number, phagocytic capacity, chemotaxis index, and hydrogen peroxide production in M phi s were significantly higher in CHF than in control rats. the production of IL-6 and TNF-alpha was similarly significantly enhanced in CHF as compared with controls. M phi s obtained from CHF rats were more responsive to LPS, suggesting the existence, in vivo, of possible factor(s) modulating the production of pro-inflammatory cytokines. the results demonstrated that there is modification of peritoneal M phi s function along CHF development, possibly contributing to the pathophysiological process in the establishment of CHF. (c) 2006 Elsevier B.V. All rights reserved.
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Effects of medial amygdala inactivation on a panic-related behavior
(Elsevier B.V., 2006-09-25) Herdade, Karina Costa Paes; Strauss, Christiana Villela de Andrade; Zangrossi Junior, Helio; Viana, Milena de Barros [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP); Pontificia Univ Catolica
In the last years, the role played by the medial nucleus of the amygdala (MeA) in the modulation of fear- and anxiety-related behaviors has been increasingly investigated. This nucleus plays an important role in the processing of predator odor-induced defensive reactions, i.e. freezing and risk-assessment behaviors. Immunohistochemical evidence also indicates that the MeA may be involved in the regulation of escape, a defensive behavior related to panic attacks. in this study, we further addressed this question by investigating the effects of the reversible inactivation of the nucleus on escape behavior generated in male Wistar rats by two different aversive stimuli, electrical stimulation of the dorsal periaqueductal gray matter (dPAG) and exposure to one of the open arms of the elevated T-maze. Results showed that intra-MeA administration of either the reversible sodium channel blocker lidocaine (34 nmol/0.2 mu l) or the GABA(A) receptor agonist muscimol (0.22 nmol/0.2 mu l) raised the threshold of aversive electrical stimulation, increasing the amount of current that applied to the dPAG evokes escape, an antiaversive effect. Local microinjection of muscimol (0.22 nmol/0.2 mu l) inhibited escape behavior in the elevated T-maze, also suggesting an antiaversive effect. in this latter test, muscimol did not affect inhibitory avoidance, a behavior associated with generalized anxiety disorder. Muscimol effect in the elevated T-maze was independent of changes in general exploratory activity as measured in an open-field. Taken together, our data corroborate previous evidences suggesting that the MeA is involved in the modulation of escape. Dysfunction of this regulatory mechanism may be of relevance in the genesis/maintenance of panic disorder. (c) 2006 Elsevier B.V. All rights reserved.
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Ultrastructural morphometric analysis of ameloblasts exposed to fluoride during tooth development
(Springer, 2006-11-01) Ribeiro, Daniel Araki [UNIFESP]; Hirota, Luciane; Cestari, Tania Mary; Ceolin, Daniele Santi; Taga, Rumio; Assis, Gerson Francisco de; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
Since a considerable amount of the world population is exposed to high doses of fluoride, it is of special concern to investigate its action mechanisms during dental enamel development. in this study, the toxicity of fluoride in ameloblasts during enamel development was evaluated by means of ultrastructural morphometric analysis. A total of 18 male Wistar rats were distributed into three groups. in Group I, the animals received deionized drinking water ad libitum (negative control) and in Groups II and III, they received sodium fluorided (NaF) drinking water at doses of 7 and 100 ppm ad libitum, respectively, for 6 weeks. Morphometric data were expressed as volume density of the most significant organelles present in the secretory and maturation phases of amelogenesis such as RER, granules, lysosomes, phagic vacuoles, microfilaments and mitochondria. the results showed that the volume density of mitochondria in the 100 ppm experimental group was 29% (P < 0.05) higher than the control group in secretory ameloblasts. No remarkable differences were found in maturation ameloblasts for all organelles evaluated. Taken together, these data indicate that NaF at high doses is able to induce cellular damage in secretory ameloblasts, whereas no noxious effect was observed during maturation stage of amelogenesis as depicted by ultrastructural analysis.
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Biocompatibility of glass-ionomer cements using mouse lymphoma cells in vitro
(Blackwell Publishing, 2006-12-01) Ribeiro, Daniel Araki [UNIFESP]; Marques, Mariangela Esther Alencar; Salvadori, Daisy Maria Favero; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
Glass-ionomer cements are widely used in dentistry as restorative materials and adhesives for composite restorations. A number of genotoxicity studies have been conducted using these materials with results conflicting so far. Thus, the approach was aimed to look at the genotoxic and cytotoxic potential of three different glass-ionomer cements available commercially (Ketac Cem, Ketac Molar and Vitrebond) by the single cell gel (comet) assay and trypan blue exclusion test, respectively. for this, such materials were exposed to mouse lymphoma cells in vitro for 1 h at 37 degrees C. Data were assessed by Kruskall-Wallis non-parametric test. the results showed that all powders assayed did not show genotoxic effects. On the other hand, the liquid from Vitrebond at 0.1% dilution caused an increase of DNA injury. Significant statistically differences (P < 0.05) in cytotoxicity provoked by all powders tested were observed for exposure at 1000 mu g mL(-1) concentration and 100 mu g mL(-1) for Ketac Molar. With respect to liquids of glass-ionomer cements evaluated, the major toxic effect on cell viability was produced at 1%, beginning at the dilution of 0.5% for Vitrebond. Taken together, these results support the notion that some components of glass-ionomer cements show both genotoxic and cytotoxic effects in higher concentrations.
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Lack of effect of prior treatment with fluoride on genotoxicity of two chemical agents in vitro
(Karger, 2007-01-01) Ribeiro, Daniel Araki [UNIFESP]; Marques, Mariangela Esther Alencar; Salvadori, Daisy Maria Favero; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)
The goal of this study was to investigate the ability of fluoride to modulate the genotoxic effects induced by the oxidative agent hydrogen peroxide (H2O2) and the alkylating agent methyl methanesulfonate (MMS) in vitro by the single-cell gel ( comet) assay. Chinese hamster ovary cells were exposed in culture for 1 h at 37 degrees C to sodium fluoride at 7-100 mu g/ml. NaF-treated and control cells were then incubated with 0-10 mu M MMS in phosphate-buffered saline (PBS) for 15 min at 37 degrees C, or 7-100 mu M H2O2 in distilled water for 5 min on ice. Negative control cells were treated with PBS for 1 h at 37 degrees C. Clear concentration-related effects were observed for the two genotoxins. Increase of DNA damage induced by either MMS or H2O2 was not significantly altered by pretreatment with NaF. the data indicate that NaF does not modulate alkylation-induced genotoxicity or oxidative DNA damage as measured by the single-cell gel ( comet) assay. Copyright (c) 2007 S. Karger AG, Basel
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DNA damage in multiple organs after exposure to chlorhexidine in Wistar rats
(Elsevier B.V., 2007-03-01) Grassi, Tony Fernando; Camargo, Elaine Aparecida de; Salvadori, Daisy Maria Favero; Marques, Mariangela Esther Alencar; Ribeiro, Daniel Araki [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
Since chlorhexidine is effective against microorganisms, it is widely recommended in dentistry. However, studies have provided evidence that chlorhexidine is toxic for a variety of cell types. in order to identify potential genotoxins in different cell types, the purpose of this study was to investigate whether chlorhexidine digluconate is able to cause, in terms of DNA damage, alterations in leukocytes, liver, kidney and urinary bladder by the single cell gel (comet) assay. Ten male Wistar rats were divided into two groups: a negative control and the experimental group treated with 3 ml of 0.12% chlorhexidine digluconate by gavage once a day for 8 days. Statistically significant increases of DNA damage was observed in leukocytes and kidney cells of the chlorhexidine digluconate treated group as depicted by the mean tail moment. Taken together, the data indicate that leukocytes and kidney cells are potential targets for primary DNA damage following oral exposure to chlorhexidine digluconate as detected by single cell gel (comet) assay. (c) 2006 Elsevier GmbH. All rights reserved.
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Genotoxicity of corrosion eluates obtained from endosseous implants
(Lippincott Williams & Wilkins, 2007-03-01) Ribeiro, Daniel Araki [UNIFESP]; Matsumoto, Mariza Akemi; Marques Padovan, Luis Eduardo; Marques, Mariangela Esther Alencar; Salvadori, Daisy Maria Favero; Universidade Federal de São Paulo (UNIFESP); Univ Sagrado Coracao; Univ Estadual Paulista
Purpose: Commercially pure titanium alloys are currently used as metallic biomaterials in implantology. Corrosion phenomena appear to play a decisive role in metallic implant long-term behavior. Thus, the goal of this study was to examine the genotoxic potential of corrosion eluates obtained from dental implants using Chinese ovary hamster cells in vitro by the single-cell gel (comet) assay. This technique detects deoxyribonucleic acid strand breaks in individual cells in alkaline conditions.Materials and Methods: the materials tested included 3 dental implants commercially available. Each of the tested materials was corroded in a solution consisting of equal amounts of acetic acid and sodium chloride (0.1 M) for 1, 3, 7, 14, and 21 days. the Chinese ovary hamster cultures were then exposed to all corrosion eluates obtained from endosseous dental implants for 30 minutes at 37 degrees C.Results: None of the eluates was found to exhibit genotoxicity, regardless of the type of dental implant used.Conclusion: the results suggest that all dental implants tested in this study did not induce deoxyribonucleic acid breakage as depicted by the single-cell gel (comet) assay.
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The effects of ruthenium tetraammine compounds on vascular smooth muscle
(Elsevier B.V., 2007-03-01) Zanichelli, Patricia Graça; Estrela, Heder Frank Gianotto; Spadari-Bratfisch, Regina Celia [UNIFESP]; Grassi-Kassisse, Dora Maria; Franco, Douglas Wagner; Universidade Estadual de Campinas (UNICAMP); Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)
The time course of the relaxation effect induced by a single dose (3 x 10(-6) mol/L) of trans-[Ru(NH(3))(4)L(NO)](3+) (L = nic, 4-pic, py, imN, P(OEt)(3), SO(3)(2-), NH(3), and pz) species and sodium nitroprusside (4 x 10(-9) mol/L) was studied in aortic rings without endothelium and pre-contracted with noradrenaline (1 x 10(-6) mol/L). All the compounds induced a relaxing effect in the aortic rings, but the intensity and time of relaxation were different. Only the species where L = py, 4-pic, and P(OEt)(3) were able to induce 100% (99-100%) of the relaxing effect during the assay. trans-[Ru(NH(3))(4)(L)(NO)](3+) (L = SO(3)(2-) and NH(3)) showed the lowest relaxing effect (36 and 37%, respectively) when compared with the other compounds. Relationship was observed between the time corresponding to half of the maximum relaxation intensity observed and, respectively, k(-NO), E([Ru(NO)])(/[Ru(NO)])(0')(3+)(2+') in trans-[Ru(NH(3))(4)(L)(NO)](3+) species and E(Ru(III)/Ru(II))(0') in trans- [Ru(NH(3))(4)(L)(H(2)O)](3+) ions. These relationships strongly suggested that the NO liberation from the reduced nitrosyl complexes was responsible for the observed relaxation. (c) 2006 Elsevier Inc. All rights reserved.
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Biocompatibility of gutta-percha solvents using in vitro mammalian test-system
(Elsevier B.V., 2007-05-01) Ribeiro, Daniel Araki [UNIFESP]; Matsumoto, Mariza Akemi; Marques, Mariangela Esther Alencar; Salvadori, Daisy Maria Favero; Universidade Federal de São Paulo (UNIFESP); São Paulo State Univ
Objectives. Taking into consideration that DNA damage and cellular death play important roles during carcinogenesis, the purpose of the present study was to evaluate in vitro genotoxic or cytotoxic effects of chloroform and eucalyptol by single cell gel (comet) assay and trypan blue exclusion test, respectively.Study design. Chloroform and eucalyptol were exposed to Chinese hamster ovary cells in culture directly for 3 hours at 37 degrees C at final concentrations ranging from 1.25 to 10 mu L/mL. the negative control group was treated with vehicle control (phosphate-buffered solution), and the positive control group was treated with methyl metasulfonate (MMS, at 1 mu g/mL concentration). All data were analyzed by the Kruskal-Wallis nonparametric test followed by the Dunn test.Results. the results showed that both gutta-percha solvents were cytotoxic at concentrations of 2.5, 5, and 10 mu L/mL (P < .05). On the other hand, both solvents did not induce DNA breakage at 1.25 mu L/mL concentration.Conclusions. These results suggest that both chloroform or eucalyptol are strong cytotoxicants, but they may not be a factor that increases the level of DNA lesions in mammalian cells.
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Absence of DNA damage in multiple organs (blood, liver, kidney, thyroid gland and urinary bladder) after acute fluoride exposure in rats
(Sage Publications Ltd, 2007-05-01) Leite, Aline de Lima; Santiago, Joel Ferreira; Levy, Flavia Mauad; Maria, Andrea Gutierrez; Fernandes, Mileni da Silva; Salvadori, Daisy Maria Favero; Ribeiro, Daniel Araki [UNIFESP]; Rabelo Buzalaf, Marflia Afonso; Universidade de São Paulo (USP); Univ Estadual Paulista; Universidade Federal de São Paulo (UNIFESP)
Fluoride has been widely used in dentistry as a caries prophylactic agent. However, there has been some speculation that excess fluoride could cause an impact on genome integrity. in the current study, the potential DNA damage associated with exposure to fluoride was assessed in cells of blood, liver, kidney, thyroid gland and urinary bladder by the single cell gel (comet) assay. Male Wistar rats aging 75 days were distributed into seven groups: Groups 1 (control), 2, 3, 4, 5, 6 and 7 received 0 (deionized water), 10, 20, 40, 60, 80 and 100 mgF/Kg body weight from sodium fluoride (NaF), respectively, by gastrogavage. These groups were killed at 2 h after the administration of the fluoride doses. the level of DNA strand breaks did not increase in all organs evaluated and at all doses of NaF tested, as depicted by the mean tail moment. Taken together, our results suggest that oral exposure to NaF did not result in systemic genotoxic effect in multiple organs related to fluoride toxicity. Since DNA damage is an important step in events leading to carcinogenesis, this study represents a relevant contribution to the correct evaluation of the potential health risk associated with chemical exposure.
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Keratoacanthoma of the lower lip complicating discoid lupus erythematosus in a 14-year-old boy
(Blackwell Publishing, 2007-05-01) Minicucci, Eliana Maria; Weber, Silke Anna Theresa; Stolf, Hamilton Ometo; Marques, Mariangela Esther Alencar; Ribeiro, Daniel Araki [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
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Differential response related to genotoxicity between eggplant (Solanum melanogena) skin aqueous extract and its main purified anthocyanin (delphinidin) in vivo
(Elsevier B.V., 2007-05-01) Azevedo, Luciana; Lima, Patricia Lepage Alves de; Gomes, Jose Carlos; Stringheta, Paulo Cesar; Ribeiro, Daniel Araki [UNIFESP]; Salvadori, Daisy Maria Favero; Universidade de São Paulo (USP); Universidade Federal de Viçosa (UFV); Universidade Federal de São Paulo (UNIFESP)
Anthocyanins are the largest group of water-soluble pigments in the plant kingdom. A number of studies have demonstrated that anthocyanins present antioxidant capacity and show inhibitory effects on the growth of some cancer cells. Thus, the goal of this study was to evaluate both the antimutagenicity/antigenotoxicity and mutagenicity/genotoxicity of aqueous extract obtained from the Solanum melanogena, a possible novel source of anthocyanin, and its main purified anthocyanin extract (delphinidin), using the single cell (comet) assay and micronucleus test. Pretreatment with higher doses of the purified anthocyanin (10 and 20 mg/kg b.w.) led to a statistically significant reduction (p < 0.05) in the frequency of micronuclei in polychromatic erythrocytes induced by cyclophosphamide. the pattern of reduction ranged from 48% to 57% independent of concentration. No apparent: genotoxicity and mutagenicity was found for either the anthocyanin or delphinidin extracts. Taken together, these results suggest that mice pre-treated with specific compounds present in anthocyanins (delphinidin) displayed a lower incidence of mutations induced by cyclophosphamide. This finding emphasizes the potential of natural colorants to prevent mutations and also the applicability of genotoxic evaluation for improving health. Furthermore, the results presented here could be an additional argument to support the use of anthocyanins in the diet. (c) 2006 Published by Elsevier B.V.
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Involvement of the histaminergic system on appetitive learning and its interaction with haloperidol in goldfish
(Elsevier B.V., 2007-05-17) Medalha, Carla Christina [UNIFESP]; Mattioli, Rosana; Universidade Federal de São Paulo (UNIFESP); Universidade Federal de São Carlos (UFSCar)
This study investigated the actions of the histaminergic system on appetitive learning and memory, and its interaction with the dopaminergic system in goldfish. It consisted of nine sessions, in which fish were tested in a four-arm tank. On day 1, the animals were habituated for 10 min. On day 2, they were placed in one arm and had to find food at the left or the right arm. Time to begin feeding was recorded, and the procedure repeated for more 3 days (training phase). On training day 4, seven groups were injected with saline, seven with haloperidol (2.0 mg/kg) and one with DMSO solution before training and after feeding, three groups received saline, six chlorpheniramine (CPA) (1.0, 4.0 and 8.0 mg/kg), and Six L-histidine (LH) (25, 50 and 100 mg/kg). Saline groups were considered as control of CPA and LH treated groups and DMSO as control of haloperidol. A non-injected group was also included. Testing occurred after 24 h. A reversal procedure was conducted 24 h after testing and repeated for 3 days. the groups receiving CPA at 1.0 and 8.0 mg/kg and LH at 25, 50 and 100 mg/kg differed between Test and Reversal day 1. Pre-treatment with haloperidol plus 8.0 mg/kg of CPA and 25 and 50 mg/kg of LH reverted the treatment effect. However, in the groups treated with 1.0 mg/kg of CPA and 100 mg/kg of LH, the difference remained. This study confirmed the interaction between the histaminergic and the dopaminergic systems on memory process in goldfish. (C) 2007 Elsevier Ireland Ltd. All rights reserved.
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DNA damage and cellular death in oral mucosa cells of children who have undergone panoramic dental radiography
(Springer, 2007-06-01) Angelieri, Fernanda; Oliveira, Gabriela Rodrigues de; Sannomiya, Eduardo Kazuo; Ribeiro, Daniel Araki [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
Background Despite wide use as a diagnostic tool in medical and dental practice, radiography can induce cytotoxic effects and genetic damage.Objective To evaluate DNA damage (micronucleus) and cellular death (pyknosis, karyolysis and karyorrhexis) in exfoliated buccal mucosa cells taken from healthy children following exposure to radiation during dental radiography.Materials and methods A total of 17 children who had undergone panoramic dental radiography were included.Results We found no statistically significant differences (P > 0.05) between micronucleated oral mucosa cells in children before and after exposure to radiation. On the other hand, radiation did cause other nuclear alterations closely related to cytotoxicity including karyorrhexis, pyknosis and karyolysis.Conclusion Taken together, these results indicate that panoramic dental radiography might not induce chromosomal damage, but may be cytotoxic. Overall, the results reinforce the importance of evaluating the health side effects of radiography and contribute to the micronucleus database, which will improve our understanding and practice of this methodology in children.
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DNA damage and nitric oxide synthesis in experimentally infected balb/c mice with Trypanosoma cruzi
(Elsevier B.V., 2007-07-01) Ribeiro, Daniel Araki [UNIFESP]; Calvi, Sueli A.; Picka, Mariele M.; Persi, Eliana; Carvalho, Thais B. de; Caetano, Priscila K.; Nagoshi, Lidiana R.; Lima, Carlos R. G.; Machado, Jussara Marcondes; Salvadori, Daisy Maria Favero; Universidade Federal de São Paulo (UNIFESP); Univ Nacl Estadual São Paulo
This study aimed to evaluate whether experimental Chagas disease in acute phase under benznidazole therapy can cause DNA damage in peripheral blood, liver, heart, and spleen cells or induce nitric oxide synthesis in spleen cells. Twenty Balb/c mice were distributed into four groups: control (non-infected animals); Trypanosoma cruzi infected; T cruzi infected and submitted to benznidazole therapy; and only treated with benznidazole. the results obtained with the single cell gel (comet) assay showed that T cruzi was able induce DNA damage in heart cells of both benznidazole treated or untreated infected mice. Similarly, T cruzi infected animals showed an increase of DNA lesions in spleen cells. Regarding nitric oxide synthesis, statistically significant differences (p < 0.05) were observed in all experimental groups compared to negative control, the strongest effect observed in the T cruzi infected group. Taken together, these results indicate that T cruzi may increase the level of DNA damage in mice heart and spleen cells. Probably, nitric oxide plays an important role in DNA damaging whereas benznidazole was able to minimize induced T. cruzi genotoxic effects in spleen cells. (c) 2006 Elsevier Inc. All rights reserved.

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