Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 43
Filtrar
1.
Reprod Domest Anim ; 50(6): 881-92, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26510939

RESUMO

Foetal membranes are essential tissues for embryonic development, playing important roles related to protection, breathing, nutrition and excretion. The amnion is the innermost extraembryonic membrane, which surrounds the foetus, forming an amniotic sac that contains the amniotic fluid (AF). In recent years, the amniotic membrane has emerged as a potential tool for clinical applications and has been primarily used in medicine in order to stimulate the healing of skin and corneal diseases. It has also been used in vaginal reconstructive surgery, repair of abdominal hernia, prevention of surgical adhesions and pericardium closure. More recently, it has been used in regenerative medicine because the amniotic-derived stem cells as well as AF-derived cells exhibit cellular plasticity, angiogenic, cytoprotective, immunosuppressive properties, antitumoural potential and the ability to generate induced pluripotent stem cells. These features make them a promising source of stem cells for cell therapy and tissue engineering. In this review, we discussed the development of the amnion, AF and amniotic cavity in different species, as well as the applicability of stem cells from the amnion and AF in cellular therapy.


Assuntos
Âmnio/citologia , Âmnio/crescimento & desenvolvimento , Terapia Baseada em Transplante de Células e Tecidos/métodos , Medicina Regenerativa/métodos , Líquido Amniótico , Animais , Diferenciação Celular , Feminino , Humanos , Células-Tronco Mesenquimais/citologia , Gravidez
2.
Plant Dis ; 97(5): 692, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-30722182

RESUMO

Tomato chlorosis virus (ToCV) and Tomato infectious chlorosis virus (TICV) are the two Solanaceae-infecting Crinivirus species (family Closteroviridae) of worldwide importance. In Brazil, only ToCV has been detected under natural conditions infecting tomato (Solanum lycopersicum), sweet pepper (Capsicum annuum), and potato (S. tuberosum), causing foliar chlorosis (1, 3). However, there are no formal reports of alternative weed hosts of ToCV. During crop surveys in Capão Bonito, São Paulo State, Brazil (May 2011), a high incidence (above 20%) of plants of the weed, cut leaf ground cherry (Physalis angulata L.) growing around and within a tomato (cv. Alambra) field with a high incidence of ToCV, were found displaying interveinal chlorosis on the lower leaves, similar to those induced by magnesium deficiency. The P. angulata plants also had high populations of whiteflies (Bemisia tabaci biotype B). Ten leaf samples were taken from individual symptomatic ground cherry and tomato plants for Crinivirus testing. Total nucleic acids were extracted from 2 g of symptomatic and healthy leaf tissues of both hosts using Whatman CF-11 cellulose (Sigma) as described (4). The purified double stranded RNA samples were used as a template in reverse transcription (RT)-PCR using specific primers targeting the p22 gene region in the genome of ToCV (2). Only the 566-bp ToCV-specific amplicon was detected in all field samples. Sequences of samples from the P. angulata and tomato cDNA amplicons were identical to each other (GenBank Accession No. JX187514) and they showed 99% identity with the ToCV RNA 1 from a tomato isolate from Florida (AY903447). This confirmed the initial hypothesis of Crinivirus infection. Cuttings of symptomatic P. angulata plants were also obtained and kept in a voile cage under greenhouse conditions together with healthy seedlings of P. angulata and the begomovirus-resistant inbred tomato line 'TX-468RG.' Fifty aviruliferous B. tabaci (biotype B) adults were placed in the cage. Similar symptoms were observed 50 days after exposure to whiteflies in both hosts. Transmission to P. angulata and to 'TX-468RG' was also confirmed via sequencing of ToCV-specific amplicon, demonstrating the infectivity of the isolate to both hosts. To our knowledge, this is the first report of P. angulata as a natural host of ToCV in Brazil. This weed is often present in the commercial fields because of its natural tolerance to herbicides currently used in tomato production. The ToCV-infected P. angulata plants might serve as alternative sources of inoculum for the surrounding tomato fields. The environmental persistence of P. angulata combined with its intense whitefly colonization might allow a year-round ToCV exposure for tomato plants under field conditions in this major production area of Brazil where at least 25 million tomato plants are cultivated annually. References: (1) J. C. Barbosa et al. Trop. Plant Pathol. 36: 256, 2011. (2) M. I. Font et al. Plant Dis. 86:696, 2002. (3) D. M. S. Freitas et al. Plant Dis. 96:593, 2012. (4) R. A. Valverde et al. Plant Dis. 74:285, 1990.

4.
Plant Dis ; 95(10): 1318, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30731658

RESUMO

Fruit rots caused by distinct fungal pathogens are commonly observed on tomatoes (Solanum lycopersicum L.) throughout all major production areas in Brazil. Samples of fruits displaying white mycelial growth associated with a profuse salmon-color sporulation were collected in greenhouse-grown tomatoes in Brasília-DF in February 2011. The isolated fungus displayed pink-to-white colonies containing several conidiophores with conidia. Mycelia displayed hyaline hyphae as much as 4 µm in diameter; conidiophores were simple or branched, 112 to 300 (360) µm long, and 2 to 4 µm wide. Conidia were produced in basipetal chains (frequently clustered), were ellipsoidal to pyriform with oblique and prominent truncate basal scars, two-celled, hyaline, and (14-) 16 to 26 (-28) × (6-) 7 to 10 (-12) µm. These characteristics allocated the specimen to Trichothecium roseum (Pers.). Koch's postulates were fulfilled for one fungal isolate by either spraying 10 intact fruits or by placing a drop of a spore suspension (adjusted to 105 conidia/ml) into three to five wounds created on 10 mature fruits of each of two tomato cultivars (Santa Clara and Dominador) by puncturing each fruit with a sterile needle. Five fruits of each cultivar were treated with sterile water as the mock-inoculated control treatment. Identical symptoms to those of the original fruit were observed only in the T. roseum-inoculated samples 5 to 7 days after using both inoculation procedures. Total DNA was extracted from a pure colony of the fungus growing on potato dextrose agar medium and used as template in PCR assays with the internal transcribed spacer (ITS)-4 (5'-TCCTCCGCTTATTGATATGC-3') and ITS-5 (5'-GGAAGTAAAAGTCGTAACAAGG-3') primer pair (2). A single amplicon of approximately 630 bp was observed and directly sequenced. Sequence analysis of the Brazilian isolate (GenBank No. JN081877) indicated identity levels of 99% with T. roseum isolates reported on Leucadendron xanthoconus in South Africa (GenBank No. EU552162) and isolates from strawberry fruits in South Korea (GenBank No. HM355750). However, phylogenetic analysis was unable to discriminate isolates of T. roseum from Passalora (GenBank No. EF432764) and Fusarium (GenBank No. GU183369) isolates, confirming the low genetic variability of the ITS region in Hypocreales (3). T. roseum has been reported to be infecting greenhouse tomatoes in the United States (4) and causing postharvest disease of tomatoes in Argentina (1). To our knowledge, this is the first report of T. roseum infecting greenhouse tomatoes in Brazil. References: (1) G. Dal Bello. Australas. Plant Dis. Notes 3:103, 2008. (2) N. L. Glass and G. C. Donaldson. Appl. Environ. Microbiol. 61:1323, 1995. (3) L. Lombard et al. Stud. Mycol. 66:31, 2010. (4) A. W. Welch, Jr. et al. Plant Dis. Rep. 59:255, 1975.

5.
Plant Dis ; 95(9): 1196, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30732032

RESUMO

Snap and common beans (Phaseolus vulgaris L.) are severely affected by Bean golden mosaic virus (BGMV) infection, so far the only begomovirus reported on these crops in Brazil (1). Samples of snap and common beans colonized by the whitefly Bemisia tabaci biotype B and displaying golden mosaic, chlorotic spots, and leaf distortion were collected in three production regions in Goiás State (Goianápolis, Luziânia, and Itaberaí) between 2003 and 2007. Total DNA extracted from leaf samples was used as template in PCR assays using universal primers targeting conserved regions of the DNA-A and DNA-B genomes (3). Begomovirus-specific amplicons were observed only with DNA template from symptomatic plants. Two single amplicons were observed for both genomic segments, indicating the presence of bipartite species in all samples. Sequence analysis of four isolates (named as GO-176, GO-260, GO-354, and GO-368) obtained from common bean samples indicated identity levels of approximately 95% with the DNA-A segment of BGMV (GenBank Accession No. FJ665283). However, the complete DNA-A sequence (GenBank Accession No. HM357459.1) of the GO-060 isolate (from a symptomatic snap bean plant collected in Goianápolis) displayed 76% identity with BGMV (GenBank Accession No. FJ665283) and 95% identity with the DNA-A of a Sida micrantha mosaic virus (SimMV) isolate (GenBank Accession No. EU908733.1) reported to be infecting okra (Abelmoschus esculentus L.) and 94.8% with a SimMV isolate reported to be infecting soybean (GenBank Accession No. FJ686693) in Brazil (2). Koch's postulates were fulfilled for the isolate GO-060 by inoculating a set of soybean and bean accessions via a biolistic approach. The ratio of positive PCR amplicons per total of inoculated plants were 15 of 16 for snap bean cv. Trepador, 9 of 10 for snap bean cv. Fartura, 18 of 24 for common bean cv. Olate Pinto, and 19 of 25 for common bean cv. Carioca. The isolate was also able to infect eight of nine soybean 'Doko' plants. Sequence analysis using symptomatic leaf samples (15 days after inoculation) confirmed SimMV as the causal agent. To our knowledge, this is the first report of a SimMV isolate infecting P. vulgaris. This virus is apparently fast expanding its host range from Malvaceae to Solanaceae species and leguminous hosts after the introduction of B. tabaci biotype B (2). More extensive surveys are necessary to access the current epidemiological importance of SimMV in both snap and common beans in Brazil. References: (1) J.C. Faria and D. P. Maxwell. Phytopathology 89:262, 1999. (2) F. R. Fernandes et al. Arch. Virol. 154:1567, 2009. (3) M. R. Rojas et al. Plant Dis. 77:340, 1993.

6.
Mycologia ; 102(5): 1163-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20943516

RESUMO

A new ascomycete genus placed in family Capnodiaceae found in the Brazilian Cerrado is described and designated Plurispermiopsis, type species P. cerradensis.


Assuntos
Ascomicetos/genética , Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Ascomicetos/ultraestrutura , Brasil , Cor , Ecossistema , Filogenia
7.
Plant Dis ; 94(2): 179-185, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30754269

RESUMO

The Ty-1 locus confers tolerance to monopartite and bipartite Begomovirus spp. (genus Begomovirus, family Geminiviridae) and this phenotype is improved in homozygous tomato lines. However, the gene Mi (Meloidogyne spp. resistance) is in repulsion phase linkage with Ty-1, which hampers the large-scale development of multiresistant inbred lines. Seventy-one Solanum (section Lycopersicon) accessions were whitefly inoculated with the bipartite Begomovirus sp. Tomato rugose mosaic virus (ToRMV) and simultaneously infested with a mixture of Meloidogyne incognita and M. javanica under greenhouse conditions in Brazil. Accessions were then transplanted into a nematode-infested field with natural ToRMV infection. A severity index was used to evaluate ToRMV reaction. Nematode evaluation was done by counting the number of galls per root system. Seventeen accessions with Meloidogyne spp. and ToRMV resistance were selected and evaluated in Spain against three monopartite Begomovirus spp. associated with the tomato yellow leaf curl virus disease, using infectious clones. Systemic infection was monitored by DNA hybridization. Five S. peruvianum accessions (PI-306811, PI-365951, LA-1609, LA-2553, and CNPH-1194) displayed nematode and broad-spectrum resistance to all Begomovirus spp. tested in both continents. From the breeding standpoint, accessions combining resistance to Meloidogyne spp. and to bipartite and monopartite Begomovirus spp. would be useful for the development of elite lines expressing all traits in homozygous condition.

8.
Eur J Paediatr Dent ; 10(2): 83-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19566374

RESUMO

AIM: This study aims to evaluate the bonding effectiveness of self-etch and etch-and-rinse adhesive systems in on intact and ground primary tooth enamel. STUDY DESIGN: Sixty primary incisors were divided into 6 groups according to the adhesive system (etch-and-rinse - Adper Single Bond 2 - SB, 2 steps self-etch -Clearfil SE Bond - SE, and 1 step self-etch - One Up Bond F Plus OBF) and to the substrate (ground or intact enamel): G1-SB/intact enamel; G2-SE/intact enamel; G3- OBF/intact enamel; G4-SB/ground enamel; G5- SE/ground enamel and G6-OBF/ground enamel. METHODS: Microshear bond test specimens were prepared with microhybrid composite and after 24h of water storage the microshear test was performed. STATISTICS: Data were submitted to statistical analysis using two-way ANOVA and Tukey's tests (p<0.05). RESULTS: Comparing the enamel characteristics (ground or intact) only when SE was used a statistically significant difference was found, as G2 (21.12+/-4.52) was statistically lower than G5 (33.29+/-5.44). Among the intact enamel groups, SB (26.11+/-7.56) was statistically superior to SE (21.12+/-4.52) and OBF (17.01+/-3.96). However, when comparisons were made among groups of ground enamel, SE (33.29+/-5.44) was significantly higher than SB (26.35+/-8.18) and OBF (17.52+/-3.46). CONCLUSION: The two-step self-etch adhesive system is a reliable alternative to etch and rinse adhesive systems on both ground and intact primary enamel.


Assuntos
Colagem Dentária , Cimentos Dentários , Esmalte Dentário , Análise de Variância , Humanos , Microscopia Eletrônica de Varredura
9.
Psychopharmacology (Berl) ; 192(1): 39-48, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17242924

RESUMO

RATIONALE: Several studies have shown the amnestic effects of ethanol (ETOH). However, while memory tasks in rodents can be markedly influenced by anxiety-like behavior and motor function, ETOH induces anxiolysis and different effects on locomotion, depending on the dose. OBJECTIVE: Verify the effects of ETOH in mice tested in the plus-maze discriminative avoidance task (PMDAT) concomitantly evaluating memory, anxiety-like behavior, and motor behavior. METHODS: ETOH acutely or repeatedly treated mice were submitted to the training session in a modified elevated plus-maze with two open and two enclosed arms, aversive stimuli in one of the enclosed arms, and tested 24 h later without aversive stimuli. Learning/memory, locomotion, and anxiety-related behavior were evaluated by aversive arm exploration, number of entries in all the arms and open arms exploration, respectively. RESULTS: Acute ETOH: (1) either increased (1.2-1.8 g/kg) or decreased (3.0 g/kg) locomotion; (2) decreased anxiety levels (1.2-3.0 g/kg); and (3) induced learning deficits (1.2-3.0 g/kg) and memory deficits (0.3-3.0 g/kg). After repeated treatment, sensitization and tolerance to hyperlocomotion and anxiolysis induced by 1.8 g/kg ETOH were observed, respectively, and tolerance to the amnestic effect of 0.6 (but not 1.8) g/kg ETOH occurred. CONCLUSION: Neither the anxiolytic nor the locomotor effects of ETOH seem to be related to its amnestic effect in the PMDAT. Additionally, data give support to the effectiveness of the PMDAT in simultaneously evaluating learning, memory, anxiety-like behavior, and motor activity by different parameters. Possible relationships between the behavioral alterations found are discussed.


Assuntos
Aprendizagem da Esquiva/efeitos dos fármacos , Depressores do Sistema Nervoso Central/farmacologia , Aprendizagem por Discriminação/efeitos dos fármacos , Etanol/farmacologia , Aprendizagem em Labirinto/efeitos dos fármacos , Animais , Ansiedade , Comportamento Animal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Memória/efeitos dos fármacos , Camundongos , Atividade Motora/efeitos dos fármacos
10.
J Phys Condens Matter ; 29(36): 365801, 2017 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-28675150

RESUMO

We introduce an exactly solvable hybrid spin-ladder model containing localized nodal Ising spins and interstitial mobile electrons, which are allowed to perform a quantum-mechanical hopping between the ladder's legs. The quantum-mechanical hopping process induces an antiferromagnetic coupling between the ladder's legs that competes with a direct exchange coupling of the nodal spins. The model is exactly mapped onto the Ising spin ladder with temperature-dependent two- and four-spin interactions, which is subsequently solved using the transfer-matrix technique. We report the ground-state phase diagram and compute the fermionic concurrence to characterize the quantum entanglement between the pair of interstitial mobile electrons. We further provide a detailed analysis of the local spin ordering including the pair and four-spin correlation functions around an elementary plaquette, as well as, the local ordering diagrams. It is shown that a complex sequence of distinct local orderings and frustrated correlations takes place when the model parameters drive the investigated system close to a zero-temperature triple coexistence point.

11.
Psychopharmacology (Berl) ; 184(1): 1-12, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16341847

RESUMO

RATIONALE: The amnesic effects of morphine may be related to its action on nociception, anxiety, or locomotion. This effect is also suggested to be related to state dependency. OBJECTIVES: The aims of this study were to verify the effects of morphine on mice tested in the plus-maze discriminative avoidance task (DAT) that uses light and noise as aversive stimuli and allows the concomitant evaluation of learning, memory, anxiety, and locomotion and also to verify the possible role of state-dependent learning in the effects of morphine. METHODS AND RESULTS: The DAT was conducted in a modified elevated plus-maze. In the training, the aversive stimuli were applied when mice entered in one of the enclosed arms, whereas in the test, no stimuli were applied. The main results showed that (1) pretraining morphine (5-20 mg/kg i.p.) induced retrieval deficits (evaluated by the time spent in the aversive arm in the test) but not acquisition deficits (evaluated by the decrease in aversive arm exploration along the training); (2) pretest morphine (5-10 but not 20 mg/kg) counteracted this deficit; (3) morphine induced hypolocomotion (decreased number of entries in the arms), irrespective of memory alterations; and (4) morphine did not alter anxiety-like behavior (evaluated by the time spent in the open arms) during the training. CONCLUSIONS: Morphine given before training induces retrieval deficits in mice tested in the DAT, and these deficits could be related to morphine-induced state-dependent learning. Neither the memory deficit induced by pretraining morphine nor the reversal of this deficit by pretest morphine seems to be related to anxiety levels or locomotor alterations.


Assuntos
Aprendizagem da Esquiva/efeitos dos fármacos , Discriminação Psicológica/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Morfina/farmacologia , Animais , Ansiedade , Relação Dose-Resposta a Droga , Luz , Masculino , Memória/efeitos dos fármacos , Camundongos , Ruído
12.
Pharmacol Biochem Behav ; 84(1): 142-7, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16753204

RESUMO

The effect of home cage conspecifics' behavior on locomotor sensitization to amphetamine (AMP) or ethanol (ETOH) were investigated. Female mice were repeatedly treated with saline or AMP (2.0 mg/kg for 13 days--Experiment 1) or saline or ETOH (1.8 g/kg for 21 days--Experiment 2) in home cages where all the animals had the same treatment (homogeneous home cages--HOM-HC) or in home cages where half of the animals were drug-treated and half of them were saline-treated (heterogeneous home cages--HET-HC). Behavioral sensitization was evaluated by the quantification of open-field locomotor activity after AMP or ETOH challenge injection, respectively. In both experiments, behavioral sensitization was potentiated in HOM-HC maintained animals. These results suggest that the behavioral sensitization phenomenon can be modified by home cage conspecifics' behavior.


Assuntos
Anfetamina/farmacologia , Comportamento Animal/efeitos dos fármacos , Etanol/farmacologia , Análise de Variância , Animais , Feminino , Camundongos
13.
Physiol Behav ; 86(1-2): 203-8, 2005 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16095638

RESUMO

World population is becoming older, and aging is a common risk factor for a number of pathologies. In this respect, it is important to study possible factors that could modify alterations implicated in the process of aging. The aim of the present study is to verify the effects of social isolation on the expression of orofacial movements in adult and old rats. Adult and old rats were housed isolated for 5 days or kept in their home cages in groups of six. Before and after this period, orofacial movements and open-field general activity were evaluated. Aging-induced orofacial movements were abolished by isolation. On the other hand, isolated adult rats presented an increase in orofacial movements. General activity was decreased by aging but was not modified by isolation. Our results indicate that social isolation produces different effects in adult and old rats, and these effects are specific for orofacial movements and not related to a decrease in general motor activity.


Assuntos
Envelhecimento/fisiologia , Músculos Faciais/inervação , Movimento/fisiologia , Isolamento Social , Animais , Comportamento Animal , Comportamento Exploratório/fisiologia , Locomoção/fisiologia , Masculino , Mastigação/fisiologia , Ratos , Ratos Endogâmicos WF , Fatores de Tempo , Língua/inervação , Língua/fisiologia
14.
Neuropharmacology ; 47(2): 263-72, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15223305

RESUMO

Tardive dyskinesia, the most serious iatrogenic movement disorder, has been tentatively associated with nigrostriatal dopaminergic supersensitivity and with oxidative stress. It is also suggested that long-term neuroleptic treatment does not cause oral dyskinesia (OD), but interacts with some substrate of brain aging, resulting in the premature emergence of OD, that can occur spontaneously with aging. In order to investigate a possible role of nigrostriatal dopaminergic supersensitivity and of oxidative stress in aging- and reserpine-induced OD, the stereotyped behavior induced by dopaminergic agonists, a functional index of dopaminergic striatal activity, as well as the striatal antioxidant enzymes glutathione peroxidase and catalase were assessed. We demonstrate that, opposite to normotensive Wistar rats (NWR), spontaneously hypertensive rats (SHR) do not develop aging- or reserpine-OD. There were no differences between NWR and SHR in stereotyped behavior or in striatal glutathione peroxidase activity. Adult and old SHR presented higher striatal catalase activity relative to NWR, and aging increased it only in SHR. The catalase inhibitor aminotriazole reverted the absence of aging- and reserpine-induced OD in SHR. Our results suggest an important role of striatal catalase in the development of reserpine- and aging-induced OD.


Assuntos
Envelhecimento/fisiologia , Catalase/fisiologia , Discinesia Induzida por Medicamentos/fisiopatologia , Neostriado/enzimologia , Reserpina , Amitrol (Herbicida)/farmacologia , Animais , Catalase/antagonistas & inibidores , Agonistas de Dopamina/farmacologia , Inibidores Enzimáticos/farmacologia , Glutationa Peroxidase/antagonistas & inibidores , Glutationa Peroxidase/metabolismo , Masculino , Neostriado/fisiologia , Estresse Oxidativo/fisiologia , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Comportamento Estereotipado/efeitos dos fármacos
15.
Neuropharmacology ; 46(6): 895-903, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15033349

RESUMO

Numerous animal and clinical studies have described memory deficits following sleep deprivation. There is also evidence that the absence of sleep increases brain oxidative stress. The present study investigates the role of hippocampal oxidative stress in memory deficits induced by sleep deprivation in mice. Mice were sleep deprived for 72 h by the multiple platform method-groups of 4-6 animals were placed in water tanks, containing 12 platforms (3 cm in diameter) surrounded by water up to 1 cm beneath the surface. Mice kept in their home cage or placed onto larger platforms were used as control groups. The results showed that hippocampal oxidized/reduced glutathione ratio as well as lipid peroxidation of sleep-deprived mice was significantly increased compared to control groups. The same procedure of sleep deprivation led to a passive avoidance retention deficit. Both passive avoidance retention deficit and increased hippocampal lipid peroxidation were prevented by repeated treatment (15 consecutive days, i.p.) with the antioxidant agents melatonin (5 mg/kg), N-tert-butyl-alpha-phenylnitrone (200 mg/kg) or vitamin E (40 mg/kg). The results indicate an important role of hippocampal oxidative stress in passive avoidance memory deficits induced by sleep deprivation in mice.


Assuntos
Hipocampo/fisiologia , Transtornos da Memória/metabolismo , Estresse Oxidativo/fisiologia , Privação do Sono/metabolismo , Animais , Hipocampo/metabolismo , Masculino , Transtornos da Memória/psicologia , Camundongos , Tempo de Reação/fisiologia , Privação do Sono/psicologia
16.
Psychopharmacology (Berl) ; 160(1): 9-18, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11862369

RESUMO

RATIONALE: The contradictory amphetamine effects on memory could be due to different protocols of amphetamine administration or the well-known anxiogenic effect of the drug. OBJECTIVE: The effects of different protocols of administration of amphetamine were investigated on mice tested in the plus-maze discriminative avoidance task (DAT), which provides simultaneous information about memory and anxiety. METHODS: Acutely pre- or post-training, 0.3, 1.0, or 3.0 mg/kg amphetamine-treated, 10-day chronically 3.0 mg/kg amphetamine-treated, 0.3 mg/kg amphetamine plus 0.25 mg/kg scopolamine and 3.0 mg/kg amphetamine plus 3.0 mg/kg tacrine-treated mice were conditioned to choose between two enclosed arms (one of which was aversive) while avoiding two open arms. Learning/memory was evaluated by the percentage time in the aversive enclosed arm (PTAV), and anxiety by the percentage time in the open arms (PTO). RESULTS: Given acutely before conditioning, amphetamine significantly decreased PTO in training, suggesting an anxiogenic effect, and significantly increased PTAV in the test, suggesting an amnestic action. Given acutely after the conditioning, no action of this drug on memory was found. After repeated treatment, the anxiogenic effect disappeared, while the amnestic effect remained. While no effects of subeffective doses of amphetamine and scopolamine co-administration were detected, tacrine attenuated the amnestic effect of amphetamine. CONCLUSIONS: Amphetamine has different effects on DAT when given pre- or post-training. While acute pre-training amnestic action is temporally correlated with an anxiogenic effect, there is tolerance to the anxiogenic but not to the amnestic effect after repeated administration. Because this acute amnestic effect of amphetamine is attenuated by tacrine, a possible relationship with cholinergic system cannot be discarded as a mechanism to amphetamine-induced amnesia in DAT.


Assuntos
Anfetamina/farmacologia , Aprendizagem da Esquiva/efeitos dos fármacos , Discriminação Psicológica/efeitos dos fármacos , Inibidores da Captação de Dopamina/farmacologia , Aprendizagem em Labirinto/efeitos dos fármacos , Animais , Inibidores da Colinesterase/farmacologia , Emoções/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Camundongos , Atividade Motora/efeitos dos fármacos , Antagonistas Muscarínicos/farmacologia , Escopolamina/farmacologia , Tacrina/farmacologia
17.
Psychopharmacology (Berl) ; 161(4): 340-7, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12073160

RESUMO

RATIONALE: While reserpine-induced oral movements (OM), an animal model of tardive dyskinesia, are more persistent in old than in adult rats, old animals present spontaneous OM, which are phenomenologically similar to those presented by reserpine-treated adult rats. We postulate that these OM may be the result of oxidative stress induced by both age and reserpine treatment. OBJECTIVES: We intended to determine the preventative effects of exogenous melatonin (one of the most important endogenous antioxidants) as well as suppression of endogenous melatonin via continuous exposure to light on reserpine- or age-induced OM in rats. METHODS: Adult (4 months of age) male Wistar rats were repeatedly treated with saline or melatonin (5 mg/kg, IP) and saline or reserpine and kept under a 12-h light/dark cycle for quantification of reserpine-induced OM as well as oxidative stress (via quantification of lipid peroxidation). To verify the effects of endogenous melatonin suppression on reserpine-induced OM, adult rats were repeatedly treated with saline or reserpine and continuously exposed to light. To verify the effects of exogenous melatonin on age-induced OM older (20 months of age) rats were long-term treated with saline or melatonin and kept under a 12-h light/dark cycle. RESULTS: Melatonin attenuated both reserpine- and age-induced OM. Reserpine enhanced striatal lipid peroxidation, that was prevented by melatonin co-administration. Continuous exposure to light increased spontaneous as well as reserpine-induced OM, indicating that endogenous melatonin may be involved in this movement disorder. CONCLUSIONS: We suggested that melatonin attenuates both reserpine- and age-induced OM in rats.


Assuntos
Discinesia Induzida por Medicamentos/tratamento farmacológico , Discinesia Induzida por Medicamentos/metabolismo , Melatonina/metabolismo , Melatonina/uso terapêutico , Fatores Etários , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Discinesia Induzida por Medicamentos/fisiopatologia , Iluminação/efeitos adversos , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/fisiologia , Masculino , Melatonina/farmacologia , Ratos , Ratos Wistar , Reserpina/farmacologia
18.
Brain Res Bull ; 60(1-2): 115-24, 2003 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-12725899

RESUMO

The effects of risperidone, an atypical neuroleptic, were investigated on two animal models of tardive dyskinesia (TD). The repeated administration of reserpine (1.0mg/kg) or haloperidol (2.0mg/kg) induces orofacial movements in mice, which are very similar to those observed in humans presenting TD. The effects of acute or repeated treatment with several doses of risperidone (0.1; 0.5; 2.0 or 4.0) on the expression and development of orofacial movements in reserpine- and haloperidol-treated male mice were investigated. The results showed that risperidone per se did not induce the development of orofacial movements. In addition, this drug was able to attenuate the expression and the development of reserpine-as well as haloperidol-induced orofacial movements. These results are in line with several clinical studies that suggest not only a lower incidence of TD in schizophrenic patients treated with risperidone, but also an antidyskinetic effect of this drug in patients previously treated with classical neuroleptics.


Assuntos
Antipsicóticos/uso terapêutico , Discinesia Induzida por Medicamentos/tratamento farmacológico , Risperidona/uso terapêutico , Administração Oral , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Haloperidol/administração & dosagem , Haloperidol/efeitos adversos , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Distribuição Aleatória , Reserpina/administração & dosagem , Reserpina/efeitos adversos
19.
Braz J Med Biol Res ; 34(12): 1561-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11717709

RESUMO

The aim of the present study was to identify the risk factors for ovarian failure in patients with systemic lupus erythematosus. Seventy-one women aged 17 to 45 years with systemic lupus erythematosus were studied. Patients were interviewed and their medical records reviewed. Demographic characteristics, clinical and serologic profiles, and menstrual and obstetric histories were recorded. Disease activity was measured by the systemic lupus erythematosus disease activity index. Serum FSH, LH, estradiol, progesterone, TSH, prolactin, and antimicrosomal and antithyroglobulin antibodies were measured. Patients who developed ovarian failure were compared to those who did not. Ovarian failure occurred in 11 patients (15.5%) and nine had premature menopause (11.3%). Cyclophosphamide administration and older patient age were found to be associated with ovarian failure. The cumulative cyclophosphamide dose was significantly higher in patients with ovarian failure than in those without this condition (18.9 vs 9.1 g; P = 0.04). The relative risk for ovarian failure in patients with cumulative cyclophosphamide dose higher than 10 g was 3.2. TSH levels were high in 100% of patients with ovarian failure who had received pulse cyclophosphamide. Ovarian failure, and premature menopause in particular, is common in patients with systemic lupus erythematosus, with the most important risk factors being cyclophosphamide dose and age. Thyroid problems may be another risk factor for ovarian failure in patients with lupus.


Assuntos
Lúpus Eritematoso Sistêmico/complicações , Insuficiência Ovariana Primária/etiologia , Adolescente , Adulto , Fatores Etários , Estudos de Coortes , Ciclofosfamida/efeitos adversos , Ciclofosfamida/sangue , Feminino , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/sangue , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Menopausa Precoce , Pessoa de Meia-Idade , Insuficiência Ovariana Primária/sangue , Insuficiência Ovariana Primária/induzido quimicamente , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco
20.
Arq Neuropsiquiatr ; 42(1): 9-13, 1984 Mar.
Artigo em Português | MEDLINE | ID: mdl-6732539

RESUMO

The neuroanatomic study of the orbitofrontal branch of the anterior cerebral artery was performed by simple and careful dissection in 50 human brains. The observation was carried out with stereoscopic magnifying glass. The results with regard to frequency and origin of the artery were the following: the orbitofrontal artery was present in 90% (45/50) of the cases on the right hemisphere and 92% (46/50) on the left hemisphere; in 26 cases (52%) on the right side and 34 cases (68%) on the opposite side, the artery arose between anterior communicating and frontopolar arteries; in 19 cases (38%) on the right side and 12 cases (24%) on the left side the vessel was not the classical first branch of the postcommunical segment of the anterior cerebral artery, it arose between the Heubner artery and the frontopolar artery. With regard at filogenetic signification of the orbitofrontal artery it has been formulated the hypothesis that the artery is homologous to posterior and anterior orbital branches of the anterior cerebral artery described by Watts in sub-human primates.


Assuntos
Artérias Cerebrais/anatomia & histologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa