Avaliação dos efeitos do biperideno, diazepam e neuropeptídeos S sobre a memória e a ansiedade na tarefa do labirinto em T elevado em camundongos

Anxiety is an emotional phenomenon, and normally it is interpreted as an adaptative behavior front to adversities. In its pathological form, anxiety can severely affect aspects related to the personal and professional life. Studies have shown a close relationship between anxiety disorders and aversive memory processing. Considering that the pharmacotherapy of anxiety disorders is still limited, innovative anxiolytic agents are needed. In this regard, neuropeptides systems are interesting therapeutic targets to the treatment of psychopathologies. Neuropeptide S (NPS), a 20-aminoacid peptide, is the endogenous ligand of a G-protein coupled receptor (NPSR), which has been reported to evoke hyperlocomotion, awakefull states, besides anxiolysis and memory improvements in rodents. This study aimed to investigate the effects of biperiden (BPR; an amnesic drug), diazepam (DZP; an anxiolytic drug) and NPS at three distinct times: pre-training, post-training, and pre-test, in order to assess anxiety and memory process in the same animal model. The elevated Tmaze (ETM) is an apparatus derived from the elevated plus-maze test, which consists of one enclosed and two open arms. The procedure is based on the avoidance of open spaces learned during training session, in which mice were exposed to the enclosed arm as many times as needed to stay 300 s. In the test session, memory is assessed by re-exposing the mouse to the enclosed arm and the latency to enter an open arm was recorded. When injected pre-training, BPR (1 mg/kg) impaired learning and memory processing; DZP (1 and 2 mg/kg) evoked anxiolysis, but only at the dose of 2 mg/kg impaired memory; and NPS 0.1 nmol induced anxiolysis without affecting memory. Post-training injection of DZP (2 mg/kg) or BPR (1 and 3 mg/kg) did not affect memory consolidation, while the post-trainning administration of NPS 1 nmol, but not 0.1 nmol, improved memory in mice. Indeed, pre-trainning administration of NPS 1 nmol did not prevent memory impairment elicited by BPR (2 mg/kg, injected before training). In the open field test, BPR 1 mg/kg and NPS 1 nmol induced hyperlocomotion in mice. In conclusion, the proposed ETM task is practical for the detection of the anxiolytic and amnesic effects of drugs. The anxiolytic and memory enhancement effects of NPS were detected in the ETM task, and reinforce the role of NPS system as an interesting therapeutic target to the treatment of anxiety disorders

Avaliação da hipermídia no processo de ensino e aprendizagem da física: o caso da gravitação

Neste artigo são apresentados os principais resultados obtidos em uma atividade realizada para avaliar um software hipermídia destinado ao ensino e à aprendizagem da Física. Para a realização desta pesquisa, foi desenvolvido, aplicado e avaliado um sistema hipermídia para o ensino de Gravitação, com base nas pesquisas em ensino de Ciências. Foram considerados também os princípios fundamentais que caracterizam a hipermídia enquanto linguagem que permite o acesso não-linear à informação e a apresentação desta com a utilização dos recursos gráficos, sonoros, interativos e de animação do computador, e ainda suas implicações para as práticas de ensino. A maior parte dos professores e dos estudantes envolvidos na pesquisa avaliou positivamente o software quanto a seus aspectos técnicos, pedagógicos e motivacionais. O estudo forneceu evidências de que a hipermídia contribui para a aprendizagem de Física de modo motivador e significativo para os alunos do ensino médio.

O problema do Hiker Dice em tabuleiro compacto: um estudo algorítmico

The Hiker Dice was a game recently proposed in a software designed by Mara Kuzmich and Leonardo Goldbarg. In the game a dice is responsible for building a trail on an n x m board. As the dice waits upon a cell on the board, it prints the side that touches the surface. The game shows the Hamiltonian Path Problem Simple Maximum Hiker Dice (Hidi-CHS) in trays Compact Nth , this problem is then characterized by looking for a Hamiltonian Path that maximize the sum of marked sides on the board. The research now related, models the problem through Graphs, and proposes two classes of solution algorithms. The first class, belonging to the exact algorithms, is formed by a backtracking algorithm planed with a return through logical rules and limiting the best found solution. The second class of algorithms is composed by metaheuristics type Evolutionary Computing, Local Ramdomized search and GRASP (Greed Randomized Adaptative Search). Three specific operators for the algorithms were created as follows: restructuring, recombination with two solutions and random greedy constructive.The exact algorithm was teste on 4x4 to 8x8 boards exhausting the possibility of higher computational treatment of cases due to the explosion in processing time. The heuristics algorithms were tested on 5x5 to 14x14 boards. According to the applied methodology for evaluation, the results acheived by the heuristics algorithms suggests a better performance for the GRASP algorithm

Subchronic Toxicity Evaluation of a Treated Urban Sewage Sludge

Disposal of tons of sludge produced daily by sewage treatment plants in large cities is a serious problem. Because recycling and application in agriculture have been proposed, the Brazilian National Environmental Council (CONAMA, 2006) issued a legal norm that regulates the use of the sewage sludge (SS) in crops. Due to the complex chemical nature of such products, characterization by analytical methods for health and environmental risk assessment has severe limitations. To overcome such limitations, it is necessary to (1) assess the toxicological potential of SS and (2) identify possible adverse effects in vivo in order to provide critical information for future environmental regulations. The present study was conducted to determine the potential toxicity of SS obtained from a representative urban treatment plant located in the São Paulo State, Brazil. Male and female Wistar rats were fed ad libitum a pelleted diet containing varying amounts of SS. No relevant clinical, hematological, urinary, or gross organ morphological alterations were observed in both genders of rats orally exposed to SS at up to 3.8 g/kg/d for 90 d. Sewage slude produced increased incidence of centrilobular hepatocyte hyperplasia at the high dose and significantly increased aspartate aminotransferease (AST) activities at all doses in both genders. Although the present data indicate some liver involvement, these alterations were considered adaptative and not toxicologically relevant, as the responses were relatively mild, not dose dependent, and no other parameters were markedly affected. The present results may contribute to the establishment of protocols for potential usage in SS agricultural soil application.

Respostas morfológicas em Guibourtia hymenifolia (Moric.) J. Leonard (Fabaceae) e Genipa americana L. (Rubiaceae), submetidas ao estresse por deficiência nutricional e alagamento do substrato

Foram estudadas as respostas plásticas em duas espécies nativas. em G. hymenifolia, não foram verificadas modificações morfológicas significativas, exceto quanto ao conteúdo de amido de reserva, que foram menores nos lotes capacidade de campo desnutrido (CCD) e alagamento desnutrido (ALD). em Genipa americana os indivíduos do lote (CCN - capacidade de campo nutrido) exibiram raízes adventícias com aerênquima distinto, mais freqüentes nas plantas do lote controle submetidas ao alagamento (ALN - alagado nutrido). Nessa última espécie, nos lotes ALN, verificou-se o surgimento de aerênquima lisógeno no caule, além da hipertrofia lenticelar. A diversidade de respostas às condições de alagamento, aliada à uma larga ocorrência de populações de Genipa americana em áreas sazonalmente inundadas, como por exemplo no Pantanal de Miranda-MS, sugere um complexo de interações entre caractes adaptativos morfológicos e fisiológicos, sendo o potencial gênico fundamental neste tipo de resposta.

Construção de conceitos de física moderna e sobre a natureza da ciência com o suporte da hipermídia

Apresentam-se os resultados de uma pesquisa sobre a construção de conceitos de Física Moderna e sobre a natureza da Ciência com o apoio da hipermídia, que envolveu a produção e avaliação de um software educacional. A proposta didática fundamentou-se na Teoria da Aprendizagem de Ausubel, em orientações para a implementação de sistemas hipermídia educacionais e em abordagens derivadas da pesquisa em Ensino de Ciências, dentre as quais o enfoque Ciência-Tecnologia-Sociedade, ponderações quanto à importância pedagógica da História e Filosofia da Ciência e considerações sobre a inserção de Física Moderna no Ensino Médio. O programa foi avaliado por pesquisadores de Ensino de Física e licenciandos de Física e, após a incorporação de algumas sugestões realizadas, foi testado por estudantes do terceiro ano do Ensino Médio de uma escola pública. Obtiveram-se indícios de que o uso do computador foi fator de motivação dos estudantes; a diversidade de elementos de mídia auxiliou-os a fixar a atenção sobre o conteúdo e favoreceu a visualização e interpretação dos fenômenos, facilitando ainda o raciocínio; o hipertexto estruturado em conformidade com princípios ausubelianos contribuiu para a percepção da relação entre os conceitos e ajudou no desenvolvimento de subsunçores para apoiar a aprendizagem subseqüente. Constatou-se que a proposta didática avaliada favoreceu a evolução das concepções da maior parte dos estudantes quanto ao conceito de equivalência massa-energia e suas implicações; às relações entre Ciência, Tecnologia e Sociedade, incluindo aspectos ambientais e políticos; ao papel da Ética no desenvolvimento e aplicação dos conhecimentos científicos; ao progresso da Ciência ao longo do tempo.

Diagnóstico de crianças com alterações específicas de linguagem por meio de escala de desenvolvimento

Alterações específicas do desenvolvimento da linguagem (AEDL) devem ser identificadas precocemente, pois tais alterações podem interferir nos aspectos sociais e escolares da criança. O objetivo dessa pesquisa foi verificar o desempenho de crianças com diagnóstico de AEDL, em comparação com o de crianças normais, por meio da Escala de Desenvolvimento Comportamental de Gesell e Amatruda (EDCGA). Foram selecionadas 25 crianças de 3 a 6 anos com o diagnóstico de AEDL (grupo estudado - GE) e 50 crianças normais da mesma faixa etária (grupo controle - GC). As crianças do GC apresentaram desempenho satisfatório e melhor que as crianças do GE, em todos os campos da escala. O valor da mediana do GE foi limítrofe nos comportamentos adaptativo e social-pessoal, já no de linguagem foi discrepantemente rebaixado. Concluímos que as alterações de linguagem interferiram na avaliação dos outros campos do desenvolvimento (adaptativo e pessoal-social). Apesar da interferência, a escala pode ser instrumento útil no diagnóstico de AEDL.

Germination of Styrax camporum Pohl. seeds in response to substrate types, moisture contents and the seed morphology

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

SOCIAL-CONTROL OF GROWTH IN FISH

This review concerns the phenomenon of heterogeneous growth (Het-G) in fish. Het-G is characterized by different growth rates between conspecifics. Although genetic determination on Het-G is recognized, grouping increases the difference in size between conspecifics. This review focuses on population factors and the mechanisms underlying the socially mediated Het-G are summarized and discussed. The aim of this paper is to arrive at a general statement explaining why grouping decreases mean growth and why it suppresses growth only in some individuals. The mechanisms described are: a) food competition, b) chemical factors released by conspecifics, and c) social stress. Social stress is analyzed in terms of the effect on appetite, digestive processes and metabolism. It is proposed that the predominant mechanism promoting socially mediated growth suppression is related to the social habit of the species. The biological significance of growth heterogeneity in fish is also discussed. Growth variability is suggested as an adaptative strategy to optimize survival of the population in a restricted space.

Roots, leaves and scapes anatomy of species of Paepalanthus subgenus Platycaulon (Eriocaulaceae)

The anatomical features of roots, leaves and scapes of the subgenus Platycaulon, genus Paepalanthus (Eriocaulaceae) that grow in the Brasilian rupestrian fields of Serra do Cipo - MG - Brazil were studied. The following main anatomical features were found: epidermis cells of varied thicknesses, chlorenchyma with compact or spread organization and leaf margin shape in the leaves; the scapes with continuous or discontinuous endodermis, divided or undivided pericycle, vascular bundles absent in the cortex and in the pith. These anatomical characteristics of the leaves and scapes occur in different species and can be used to separate them into Divise or Conferti sections. It was possible to confirm the proposed taxonomy based only on the morphological characteristics. Other anatomical features such as: presence or absence of air in the cortex roots and hypodermis which originate water parenchyma reserves in the mesophyll, can be an adaptative response that plants towards produce the environmental factors in this ecosystem.

EFFECT OF MACROPHAGE BLOCKADE ON THE RESISTANCE OF INBRED MICE TO PARACOCCIDIOIDES-BRASILIENSIS INFECTION

The effect of macrophage blockade on the natural resistance and on the adaptative immune response of susceptible (B10.D2/oSn) and resistant (A/Sn) mice to Paracoccidioides brasiliensis infection was investigated. B10.D2/oSn and A/Sn mice previously injected with colloidal carbon were infected ip with yeast cells to determine the 50% lethal dose, and to evaluate the anatomy and histopathology, macrophage activation, antibody production and DTH reactions. Macrophage blockade rendered both resistant and susceptible mice considerably more susceptible to infection, as evidenced by increased mortality and many disseminated lesions. P. brasiliensis infection and/or carbon treatment increased the ability of macrophages from resistant mice to spread up to 25 days after treatment. In susceptible mice the enhanced spreading capacity induced by carbon treatment was impaired at ail assayed periods except at 1 week after infection. Macrophage blockade enhanced DTH reactions in resistant mice, but did not alter these reactions in susceptible mice, which remained anergic. To the contrary, macrophage blockade enhanced specific antibody production by susceptible mice, but did nor affect the low levels produced by resistant mice. The effect of macrophage blockade confirms the natural tendency of resistant animals to mount DTH reactions in the course of the disease and the preferential antibody response developed by susceptible mice after P. brasiliensis infection. on the whole, macrophage functions appear to play a fundamental role in the natural and acquired resistance mechanisms to P. brasiliensis infection.

A linearly tunable low-voltage CMOS transconductor with improved common-mode stability and its application to (gm)-C filters

A linearly tunable low-voltage CMOS transconductor featuring a new adaptative-bias mechanism that considerably improves the stability of the processed-signal common,mode voltage over the tuning range, critical for very-low voltage applications, is introduced. It embeds a feedback loop that holds input devices on triode region while boosting the output resistance. Analysis of the integrator frequency response gives an insight into the location of secondary poles and zeros as function of design parameters. A third-order low-pass Cauer filter employing the proposed transconductor was designed and integrated on a 0.8-mum n-well CMOS standard process. For a 1.8-V supply, filter characterization revealed f(p) = 0.93 MHz, f(s) = 1.82 MHz, A(min) = 44.08, dB, and A(max) = 0.64 dB at nominal tuning. Mined by a de voltage V-TUNE, the filter bandwidth was linearly adjusted at a rate of 11.48 kHz/mV over nearly one frequency decade. A maximum 13-mV deviation on the common-mode voltage at the filter output was measured over the interval 25 mV less than or equal to V-TUNE less than or equal to 200 mV. For V-out = 300 mV(pp) and V-TUNE = 100 mV, THD was -55.4 dB. Noise spectral density was 0.84 muV/Hz(1/2) @1 kHz and S/N = 41 dB @ V-out = 300 mV(pp) and 1-MHz bandwidth. Idle power consumption was 1.73 mW @V-TUNE = 100 mV. A tradeoff between dynamic range, bandwidth, power consumption, and chip area has then been achieved.

The Variable Sample Size (X)over-bar Chart with Estimated Parameters

The VSS X chart, dedicated to the detection of small to moderate mean shifts in the process, has been investigated by several researchers under the assumption of known process parameters. In practice, the process parameters are rarely known and are usually estimated from an in-control Phase I data set. In this paper, we evaluate the (run length) performances of the VSS chart when the process parameters are estimated, we compare them in the case where the process parameters are assumed known and we propose specific optimal control chart parameters taking the number of Phase I samples into account.

Metabolic adaptations induced by long-term fasting in quails

After up to 21 days without food, adult male quails (Coturnix coturnix japonica) lost about 45% of the initial body weight (100-150 g). As in naturally fast-adapted and larger birds, three phases were identified during prolonged fasting in quails. Phase I lasted 2-3 days and was characterized by a rapid decrease in the rate of body weight loss and high fat mobilization. Phase II was longer and characterized by a slow and steady decline in the rates of body weight loss and of nitrogen excretion. The third (critical) period was marked by an abrupt increase in the rates of body weight loss and of nitrogen excretion. Despite their small size, the duration of phase II in quails was relatively long, a clear advantage for the study of the relationships between the several metabolic events that occur during this crucial adaptative period. Also, the beginning of phase III could be precisely determined. Changes in blood glucose, plasma FFA and triacylglycerols levels, as well as in liver and carcass lipid content were similar to those found in other species of birds. Therefore, quails seem to be a suitable model to investigate the biochemical mechanisms involved in the metabolic adjustments to prolonged food deprivation in non fasting-adapted birds. © 1995.

Bupivacaína, Ropivacaína e Levobupivacaína em Analgesia e Anestesia de Parto. Repercussões Materno-Fetais

Background and Objectives - Bupivacaine has been a very useful local anesthetic in Obstetrics in spite of its potential cardiotoxicity. In obstetric analgesia, ropivacaine is preferred to bupivacaine, and levobupivacaine is less cardiotoxic than the racemic mixture. The aim of this study was to compare the maternal-fetal effects of bupivacaine, ropivacaine and levobupivacaine in obstetric analgesia and anesthesia. Methods - Participated in this study 33 term pregnant women, physical status ASA I and II submitted to epidural anesthesia who received 18.75 mg (in 15 ml completed with 9% saline) of: GI - bupivacaine, GII - ropivacaine, and GIII - levobupivacaine. Pain intensity, sensory block level, onset time, quality of analgesia, motor block intensity, analgesia duration and time for labor resolution were evaluated. For vaginal delivery, 40 mg (in 8 ml of saline) of the same local anesthetic were used; for cesarean delivery, the dose has been mg in 20 ml solution. Newborns of these mothers were evaluated through the Apgar score in minutes 1, 5 and 10, and through the Amiel-Tison method (neurologic and adaptative capacity score - NACS) at 30 min, 2 h, and 24 h. Results - There were no significant statistical differences among groups as to sensory block level, onset time, quality of analgesia, labor analgesia duration, time for labor resolution, and Apgar scores at minute 1. Ast to motor block, GIII > GII and GI was intermediary. In relation to pain intensity, there was a trend for GI > GIII. For Apgar scores in minute 5, GII > (GI = GIII), and in minute 10 (GI = GII) < GIII. NACS at 2 h showed, GII > GI > GIII, and at 24 h, GII > GIII > GI. Conclusions - Ropivacaine has relieved maternal pain with less motor block. Newborns of GII mothers (ropivacaine) showed the best Apgar and NACS scores.