Glial cells have been implicated in temporal lobe epilepsy in humans and in its models. Astrocytes are lost in several brain regions after acute seizures induced by pilocarpine and may suffer hyperplasia at subsequent time points. This study investigated the effect of N-methyl-(2S,4R)-trans-4-hydroxy-L-proline (NMP) on astrocytes exposed to cytotoxic concentrations of pilocarpine. Astrocytes were incubated with pilocarpine (half maximal inhibitory concentration (IC50)=31.86 mM) for 24 h. Afterwards, they were treated with NMP at concentrations ranging from 3.12 to 100 μg/mL for 24 h. Cell viability was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cytoplasmic reactive oxygen species (ROS) and mitochondrial transmembrane potential (ΔΨm) were analyzed by flow cytometry using 2',7'-dichlorofluorescein diacetate (DCFH-DA) and rhodamine-123 (Rho123), respectively. Expression of glial fibrillary acidic protein (GFAP) and voltage-dependent anion channel-1 (VDAC-1) were measured by western blot. Pilocarpine significantly decreased cell viability and mitochondrial potential and increased ROS concentration significantly by 6.7 times compared to the control. NMP concentrations ≥25 µg/mL protected astrocytes against pilocarpine-induced injury in a concentration-dependent manner. Concomitantly, NMP reduced cytoplasmic ROS accumulation to 27.3, 24.8, and 12.3% in the groups treated with 25, 50, and 100 µg/mL NMP, respectively. NMP also protected mitochondria from pilocarpine-induced depolarization. These effects were associated with improvement of pilocarpine-induced GFAP and VDAC-1 overexpression, which are important biomarkers of astrocyte dysfunction. In conclusion, the improvement of ROS accumulation, VDAC-1 overexpression, and mitochondrial depolarization are possible mechanisms of the NMP protective action on reactive astrocytes.

RESUMO A utilização de diferentes doses de herbicidas pode promover resposta fisiológica diferenciada em gramíneas do mesmo gênero. Este trabalho foi proposto com o objetivo de avaliar as respostas fisiológicas de B. ruziziensis e B. decumbens submetidas aos herbicidas glyphosate e fluazifop-p-butyl. Os tratamentos foram arranjados no esquema fatorial 2 x 6, com cinco repetições, sendo duas gramíneas (B. decumbens cv. Basilisk e B. ruziziensis) e seis doses dos herbicidas: 0,00, 0,25, 0,50, 1,00, 1,5 e 2,00 vezes a dose comercial indicada pelos fabricantes. Aos 7, 15, 21 e 30 dias após aplicação dos herbicidas (DAA), foi avaliada a eficiência de captação de energia luminosa sensíveis ao glyphosate que ao fluazifop-p-butyl. Com relação ao fluazifop-p-butyl, B. ruziziensis foi mais sensível que B. decumbens, e, aos 45 dias após o corte, B. decumbens submetida a doses de até 100 g ha-1 foi capaz de regenerar seu aparato fotossintético.

ABSTRACT Different doses of herbicides can promote a differentiated physiological response in grasses of the same genus. This study has been proposed in order to evaluate physiological responses of B. ruziziensis and B. decumbens submitted to glyphosate and fluazifop-p-butyl. Treatments were distributed in a 2 x 6 factorial design with five repetitions, being two grasses: B. decumbens cv. Basilisk and B. ruziziensis with six doses of herbicides: 0.00; 0.25; 0.50; 1.00; 1.5 and 2.00 times the commercial dose recommended by manufacturers. At 7, 15, 21, and 30 days after herbicide application (DAA) chlorophyll luminous energy uptake efficiency was evaluated. Plants subjected to glyphosate at 7 days after application (DAA) showed minimum fluorescence of 270 and 245 quantum-1 electrons to B. ruziziensis and B. decumbens, respectively, levels increased by 350% when compared to the control, and at 15 DAA the treated plants have completely dried up. At 15 DAA, both forage species submitted to the fluazifop-p-butyl showed a 25% reduction in Fv/Fm ratio compared with the control and there was no significant difference between the lowest and highest doses applied. B. ruziziensis and B. decumbens are more sensitive to glyphosate than fluazifop-p-butyl. Regarding fluazifop-p-butyl, B. ruziziensis was more sensitive than B. decumbens and at 45 days after cutting B. decumbens plants submitted to doses up to 100 g ha-1 were able to regenerate their photosynthetic apparatus.

RESUMO Objetivou-se com este trabalho avaliar a seletividade do capimbraquiária e do capim-ruziziensis, submetidos à aplicação de herbicidas em pósemergência. O experimento foi realizado em casa de vegetação. O delineamento experimental foi em blocos casualizados com cinco repetições. Os tratamentos foram dispostos em esquema fatorial (8 x 2) + 2, sendo oito herbicidas: nicosulfuron, clomazone, glyphosate, fluazifop-p-butil + fomesafen, lactofen, fomesafen, fluazifopp-butil e mesotrione, em duas espécies forrageiras, Brachiaria decumbens cv. Basilisk (capim-braquiária) e Brachiaria ruziziensis (capim-ruziziensis), mais duas testemunhas, sem aplicação dos herbicidas. Os herbicidas estudados apresentaram menor intoxicação nas plantas de capim-braquiária, quando comparadas às de capim-ruziziensis. O nicosulfuron e glyphosate promoveram maior intoxicação no capim-braquiária e capim-ruziziensis, em comparação aos demais herbicidas. O glyphosate, fluazifop-p-butil + fomesafen, fluazifop-p-butil, mesotrione e nicosulfuron afetaram a relação fluorescência variável/fluorescência máxima (Fv/Fm) em ambas as espécies, indicando efeito na cadeia de transporte de elétrons promovido por esses herbicidas. Os resultados demonstraram que as plantas de capim-braquiária e capim-ruziziensis apresentam maior suscetibilidade ao glyphosate, fluazifop-pbutil + fomesafen, fluazifop-p-butil, mesotrione e nicosulfuron.

ABSTRACT This study was conducted in order to evaluate the selectivity of signal grass and congo grass, submitted to post-emergence herbicide application. The experiment was conducted under greenhouse conditions, in Diamantina, Minas Gerais state, and it was arranged in a randomized block design, with five replications. Treatments were set in factor scheme (8 x 2) + 2. Eight herbicides (nicosulfuron; clomazone; glyphosate; fluazifop-p-butyl + fomesafen; lactofen; fomesafen; fluazifop-p-butyl and mesotrione) were applied in doses recommended by the manufacturer on two fodder species: Brachiaria decumbens cv. Basilisk (signal grass) and Brachiaria ruziziensis (congo grass); in addition, there were two control samples without herbicide application, for a total of 18 treatments. The evaluated herbicides showed less intoxication on signal grass when compared to congo grass. Nicosulfuron and glyphosate promoted higher intoxication on both species when compared to the other herbicides. Glyphosate, fluazifop-p-butyl + fomesafen, fluazifop-p-butyl, mesotrione and nicosulfuron affected the ratio variable / maximum fluorescence (Fv/Fm) in both species, indicating an effect provided by these herbicides on the electron transport chain. Results demonstrated that signal grass and congo grass have higher susceptibility to glyphosate, fluazifop-p-butyl + fomesafen, fluazifop-p-butyl, mesotrione and nicosulfuron. congo grass shows higher susceptibility to the studied herbicides when compared to signal grass.

Resistance training evokes myocardial adaptation; however, the effects of a single resistance exercise session on cardiac performance are poorly understood or investigated. This study aimed to investigate the effects of a single resistance exercise session on the myocardial contractility of spontaneously hypertensive rats (SHRs). Male 3-month-old SHRs were divided into two groups: control (Ct) and exercise (Ex). Control animals were submitted to sham exercise. Blood pressure was measured in conscious rats before the exercise session to confirm the presence of arterial hypertension. Ten minutes after the exercise session, the animals were anesthetized and killed, and the hearts were removed. Cardiac contractility was evaluated in the whole heart by the Langendorff technique and by isometric contractions of isolated left ventricular papillary muscles. SERCA2a, phospholamban (PLB), and phosphorylated PLB expression were investigated by Western blot. Exercise increased force development of isolated papillary muscles (Ex=1.0±0.1 g/mg vs Ct=0.63±0.2 g/mg, P<0.05). Post-rest contraction was greater in the exercised animals (Ex=4.1±0.4% vs Ct=1.7±0.2%, P<0.05). Papillary muscles of exercised animals developed greater force under increasing isoproterenol concentrations (P<0.05). In the isolated heart, exercise increased left ventricular isovolumetric systolic pressure (LVISP; Δ +39 mmHg; P<0.05) from baseline conditions. Hearts from the exercised rats presented a greater response to increasing diastolic pressure. Positive inotropic intervention to calcium and isoproterenol resulted in greater LVISP in exercised animals (P<0.05). The results demonstrated that a single resistance exercise session improved myocardial contractility in SHRs.

O solo é um ambiente bastante heterogêneo que permite o estabelecimento de diversas populações de microrganismos, cujo equilíbrio é afetado por fatores bióticos e abióticos. Este trabalho teve como objetivo avaliar o efeito de doses dos herbicidas mesotrione e fluazifop-p-butil e duas épocas de avaliação na atividade e biomassa microbiana do solo cultivado com o cultivar de mandioca Cacau-UFV, bem como a colonização das raízes por fungos micorrízicos arbusculares. Dois ensaios foram realizados em ambiente protegido, constituindo-se da aplicação em pós-emergência do mesotrione nas doses de 72, 108, 144 e 216 g ha-1 e do fluazifop-p-butil nas doses de 100, 150, 200 e 300 g ha-1, além de uma testemunha sem aplicação. Aos 30 e 60 dias após a aplicação (DAA) dos herbicidas, amostras de solo foram coletadas para determinação da taxa respiratória do solo (TR), do carbono da biomassa microbiana (CBM) e do quociente metabólico (qCO2), sendo também avaliada a colonização das raízes por fungos micorrízicos arbusculares. O fluazifop-p-butil aumentou a TR, o CBM e a porcentagem de raízes de mandioca colonizada por fungos micorrízicos na avaliação realizada aos 60 DAA. Já os maiores efeitos do mesotrione sobre os indicadores microbiológicos do solo foram até os 30 DAA, e aos 60 DAA as alterações foram minimizadas. Conclui-se que os herbicidas alteram os indicadores microbianos do solo, sendo os efeitos dependentes do produto, da dose aplicada e também da época de avaliação.

Soil is a very heterogeneous environment that allows the establishment of wide range of microorganisms populations, whose balance is affected by biotic and abiotic factors. This study has aimed to assess the effect of doses of mesotrione and fluazifop-p-butyl herbicides and two assessment periods on microbial activity and biomass of soil cultivated with cassava Cacau-UFV cultivar, besides the root colonization by arbuscular mycorrhizal fungi. Two trials were conducted in a protected environment where was realized post-emergence application of mesotrione in the doses of 72, 108, 144 and 216 g ha-1 and fluazifop-p-butyl in the doses of 100, 150, 200 and 300 g ha-1, besides a control without application. Soil samples were collected for determination of soil respiratory rate (RR), microbial biomass carbon (MBC), metabolic quotient (qCO2), and colonization of roots by arbuscular mycorrhizal fungi at the 30 and 60 days after applications (DAA) of the herbicides. Fluazifop-p-butyl increased the RR, MBC and the percentage of cassava roots colonized by mycorrhizal fungi in the assessment performed at 60 DAA. The larger effects of mesotrione on soil microbial indicators were up to 30 DAA, being the changes minimized at 60 DAA. It is concluded that the herbicides alter the soil microbial indicators, with effects dependent of the product, of dose applied and also of the period of assessment.

A Spiranthera odoratissima A. St.-Hil. (manacá) é um arbusto cujas raízes são utilizadas popularmente contra dores musculares, de estômago e de cabeça, disfunções hepáticas, reumatismo, e como estimulante do apetite. As folhas são empregadas como depurativo do sangue, nas afecções renais e hepáticas. O objetivo deste trabalho foi realizar o estudo morfo-anatômico de S. odoratissima, bem como a triagem fitoquímica, a determinação dos teores de água, cinzas totais e insolúveis em ácido. O material vegetal foi coletado em Leopoldo de Bulhões/ Goiás e os estudos morfo-anatômicos e a triagem fitoquímica foram realizados utilizando as técnicas convencionais. Verificou-se que a folha é hipoestomática, com estômatos anomocíticos e a epiderme apresenta papilas na face abaxial. O mesofilo é dorsiventral e a nervura principal possui drusas de oxalato de cálcio e cavidades secretoras. O pecíolo apresenta sistema vascular em forma circular. Na raiz, em crescimento primário, observou-se cilindro vascular com organização diarca. Na prospecção fitoquímica detectaram-se fenóis, taninos, cumarinas, flavonoides, triterpernos/esteróis, antraquinonas e antocianinas nas folhas e alcaloides, cumarinas, amido e saponinas nas raízes. Esses resultados são parâmetros importantes para o controle de qualidade dessa matéria-prima vegetal.

Spiranthera odoratissima A. St.-Hil. (manacá) is a shrub whose roots are popularly used against stomach pains, headache, muscle pain, liver disorders, rheumatism and as an appetite stimulant. The leaves are used as a blood depurative and for liver and kidney disease. The purpose of this work was to perform the morphological and anatomical study, the phytochemical screening and determine the water content and the levels of total and acid of S. odoratissima. The plant material was collected in Leopoldo de Bulhões/ Goiás and the morpho-anatomical studies and the phytochemical screening were performed using conventional techniques. It was verified that the leaf is hypostomatic, with anomocytic stomata and the epidermis has papillae on the abaxial surface. The mesophyll is dorsiventral and the midrib presents druses of calcium oxalate and secretory cavities. The petiole has a circular vascular system. The root in primary growth presents vascular cylinder with diarchic organization. Phenols, tannins, coumarins, flavonoids, triterpenes/sterols, anthraquinones and anthocyanins were detected in the phytochemical screening of the leaves, and alkaloids, coumarins, saponins and starch were detected in the roots. These results are important parameters for the quality control of the vegetal raw material.

Neste trabalho, avaliou-se a taxa fotossintética e a eficiência do uso da água em cultivares de mandioca (Coimbra, Platina, IAC-12, Coqueiro e Cacau-UFV), pulverizados com cinco doses do mesotrione (0, 72, 108, 144 e 216 g ha-1). Aos 45 dias após aplicação do herbicida, foram avaliados o CO2 consumido, o carbono interno, a taxa fotossintética, a condutância estomática de vapores de água, a taxa de transpiração, a temperatura da folha e a eficiência do uso da água. O cultivar Platina mostrou-se menos afetado pelo mesotrione. Apenas neste cultivar as doses aplicadas de 144 e 216 g ha-1 não alteraram a taxa fotossintética das plantas. A temperatura da folha dos cultivares de mandioca também não foi alterada pelo herbicida; entretanto, observou-se redução na eficiência de uso da água para o cultivar Coqueiro.

Efficiency of the photosynthetic rate and water use was evaluated in cassava cultivars (Coimbra, Platina, IAC-12, Coqueiro, and Cacau-UFV), sprayed with five mesotrione rates (0, 72, 108, 144, and 216 g ha-1). CO2 consumed, internal carbon, photosynthetic rate, water vapor stomatal conductance, transpiration rate, leaf temperature, and water use efficiency were assessed 45 days after application of the herbicide. Platina cultivar was found to be less affected by mesotrione. Only in this cultivar, the applied rates of 144 and 216 g ha-1 did not alter the photosynthetic rate of the plants. The leaf temperature of the cassava cultivars was not affected by the herbicide, either; however, reduced water use efficiency was observed in the Coqueiro cultivar.

Avaliaram-se a rentabilidade e a viabilidade econômica da implantação de um sistema de produção de leite em free-stall. Foi realizada uma pesquisa técnico-mercadológica para definir os investimentos necessários e determinar os custos de cada fator de produção. Considerou-se um modelo de produção composto por 100 vacas em lactação, com produção média total de 2595 litros de leite por dia. O custo operacional total mensal foi de R$27.787,39, tendo a nutrição como a variável de maior relevância, representando 62,7% do custo. Para a receita bruta mensal, obteve-se o valor de R$43.817,50 e a consequente receita líquida mensal de R$16.030,11. Observou-se rentabilidade de 12,2% ao ano, com valor presente líquido negativo de R$131.627,39. Concluiu-se que o modelo proposto mostrou-se economicamente inviável levando-se em consideração os preços estimados.

The economical profitability and viability of the implantation of a milk production system in free stall were evaluated. A technical-market analysis was done to define the necessary investment as well as to determine the costs of each production factor. A production model with 100 lactating cows averaging 2,595 liters of daily production was considered. The total monthly operational cost was R$27,781.39 showing that nutrition is the variable with higher relevance (62.7% of the cost). For the monthly gross income a value of R$43,817.50 was obtained and, consequently, the monthly net income (NI)was R$16,030.11. A 12.2% profitability per year from NI rendering a deficit net value of R$131,627.39. Considering the estimated prices it is concluded that the proposed model was economically unfeasible.

Chronic lead exposure induces hypertension in humans and animals, affecting endothelial function. However, studies concerning acute cardiovascular effects are lacking. We investigated the effects of acute administration of a high concentration of lead acetate (100 µΜ) on the pressor response to phenylephrine (PHE) in the tail vascular bed of male Wistar rats. Animals were anesthetized with sodium pentobarbital and heparinized. The tail artery was dissected and cannulated for drug infusion and mean perfusion pressure measurements. Endothelium and vascular smooth muscle relaxation were tested with acetylcholine (5 µg/100 µL) and sodium nitroprusside (0.1 µg/100 µL), respectively, in arteries precontracted with 0.1 µM PHE. Concentration-response curves to PHE (0.001-300 µg/100 µL) were constructed before and after perfusion for 1 h with 100 µΜ lead acetate. In the presence of endothelium (E+), lead acetate increased maximal response (Emax) (control: 364.4 ± 36, Pb2+: 480.0 ± 27 mmHg; P < 0.05) and the sensitivity (pD2; control: 1.98 ± 0.07, 2.38 ± 0.14 log mM) to PHE. In the absence of endothelium (E-) lead had no effect but increased baseline perfusion pressure (E+: 79.5 ± 2.4, E-: 118 ± 2.2 mmHg; P < 0.05). To investigate the underlying mechanisms, this protocol was repeated after treatment with 100 µM L-NAME, 10 µM indomethacin and 1 µM tempol in the presence of lead. Lead actions on Emax and pD2 were abolished in the presence of indomethacin, and partially abolished with L-NAME and tempol. Results suggest that acute lead administration affects the endothelium, releasing cyclooxygenase-derived vasoconstrictors and involving reactive oxygen species.

Um modelo experimental de sinovite em pôneis foi usado para avaliar o efeito do parecoxib, um antiinflamatório não-esteroidal (AINE) seletivo injetável. Cinco dias após indução da sinovite, três pôneis foram tratados com 0,55mg/kg/dia (IV) de parecoxib e três receberam solução salina 0,9% (IV) por cinco dias. A avaliação de parâmetros clínicos dos animais e físico-químicos do líquido sinovial foi realizada antes da indução de sinovite, antes e 12, 24, 48, 72, 96 e 120 horas após o início do tratamento. A injeção intra-articular com adjuvante completo de Freund induziu sinovite de intensidade moderada a grave. Os pôneis tratados com parecoxib apresentaram diminuição do grau de claudicação; manutenção da flexão articular, do comprimento do passo, da temperatura retal e da freqüência cardíaca; e atenuação do grau de efusão articular. Embora o parecoxib, na dose utilizada, não tenha apresentado efeito sobre os parâmetros do líquido sinovial das articulações com sinovite, sua ação antipirética, antiinflamatória e principalmente analgésica foi observada.

An experimental synovitis model was used in ponies to evaluate the effect of parecoxib, a selective non steroidal anti-inflammatory drug (NSAID). Five days after synovitis induction, three ponies received parecoxib (IV) 0.55mg/kg/day and three ponies received sterile 0.9% saline solution (IV) for five days. Clinical parameters and synovial fluid were evaluated before synovitis induction, prior treatment and 12, 24, 48, 96, and 120 hours after the first treatment. The intra-articular injection of Freund's complete adjuvant induced a moderate to severe synovitis. The parecoxib treated ponies showed lameness reduction; maintenance of stride length, articular flexion, temperature, and heart rate; and attenuation of articular effusion. Although the used dosage of parecoxib had no effect on evaluated synovial fluid parameters, antipyretic, anti-inflammatory, and especially analgesic effects were observed.

Com o objetivo de avaliar a germinação de sementes de soja e o desenvolvimento inicial de plântulas, cujas plantas-mãe foram tratadas com subdoses de herbicidas sistêmicos nâo-seletivos em estádios avançados de desenvolvimento, realizaram-se experimentos a campo, em laboratório e em casa-de-vegetação na Faculdade de Agronomia da UFRGS, em Porto Alegre, RS, durante o período 1995/97. Os tratamentos constaram das aplicações a campo dos herbicidas 2,4-D nas doses de 5 e l0g/ha e.a., imawpyr a 25 e 50g/ha e.a. e sulfosate a 25 e 50g/ha e.a., usados no início do florescimento (estádio R1) ou no início da formação de legumes (estádio R3) das plantas de soja. Comprovou-se que a aplicação de imawpyr sobre plantas de soja no início da formação de legumes reduz, a germinação das sementes nelas formadas. A aplicação de 2,4-D e de sulfosate não afeiam a germinação das sementes de soja, nas doses testadas, independente se aplicados no início do florescimento ou da formação de legumes das plantas-mãe. Os parâmetros altura de plântula, massa seca da parte aérea, da parte radicular e total das plântulas da progênie não são afetados pêlos herbicidas aplicados nos estádios Ri e Rj das plantas-mãe de soja. No entanto, as aplicações dos herbicidas 2,4-D (a 5 e l0g/ha e.a.), imazapyr (a 25 e 50g/ha e.a.) e sulfosate (a 25 e 50g/ha e.a.), efetuadas no início da formação dos legumes das plantas-mãe, reduzem os comprimentos do hipocótilo e da raiz, das plântulas da progênie.

The purpose of ïhis research was to evaluate germination of soybean seeds and initial development of seediings, whose mother plants were treated with sub-rates of svstemic nonselective herbicides during late stages of development. Field, laboratory, and greenhouse experiments were carried ouï aï Agronomy School of UFRGS, in Porto Alegre, RS, during the period 1995/97. Treatments consisted offield appiications of the herbicides 2,4-D at rates of 5 and l0g/ha a. e., imazapvr at 25 and 50g/ha a.e., and sulfosate at 25 and 50g/ha a.e. The se herbicides were sprayed eiïher at beginning of flowering (R1 stage) or at beginning ofpod development (R3 stage) of soybean plants. It was proved that appiication of imazapyr on sovbean plants at beginning of pod development decreased germination of seeds formed on those plants. The appiication of 2,4-D and sulfosate did not ajfect soybean seed germination, at tested rates, independentiy if appiied eiïher at beginning of flowering or pod development of the mother plants. Seediing ïzeight, dry matter of shoots, of roots and total dry matter of seediings of the progeny were not affected by herbicides appiied at Ri and Rs stages of sovbean plants. However, sprayings of herbicides 2,4-D (at 5 and l0g/ha a.e.), imazapyr (at 25 and 50g/ha a.e.), and sulfosate (at 25 and 50g/ha a.e.), appiied at beginning of pod development of mother plants, in general reduced hvpocotyl and root lengtli of sovbean seed-lings of tire progeny.