Structural evaluation of the effects of chronic ethanol ingestion on the testis of Calomys callosus

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação em escala laboratorial da utilização do processo eletrolítico no tratamento de águas

Water treatment uses chlorine for disinfection causing formation of trihalomethanes. In this work, an electrolytic water pre-treatment was studied and applied to the water from a fountainhead. The action against microorganisms was evaluated using cast-iron and aluminum electrodes. Assays were made in laboratory using the electrolytic treatment. After 5 min of electrolysis the heterotrophic bacteria count was below 500 cfu/mL and complete elimination of total and fecal coliforms was observed. Using electrolytic treatment as a pretreatment of conventional tap water treatment is proposed.

Caffeine effect on mortality and oviposition in successive generations of Aedes aegypti

OBJETIVO: Experimentos anteriores mostraram que a cafeína bloqueia o desenvolvimento de Aedes aegypti (Diptera, Culicidae) na fase larval, inibindo conseqüentemente a produção de adultos. O objetivo do estudo foi obter dados que pudessem sugerir desenvolvimento de resistência dos mosquitos à cafeína. MÉTODOS: Foi avaliada a produção de adultos em gerações sucessivas, a partir de ovos produzidos na geração anterior e a taxa de oviposição em cada geração, utilizando meios contendo cafeína a 200 e 500 µg/ml e água de torneira proveniente de poço artesiano como controle. Os experimentos foram conduzidos em São José do Rio Preto, entre 2002 e 2005. Nos testes estatísticos foram utilizados a análise exploratória de dados e algoritmos de alisamento. RESULTADOS: Ocorreu redução crescente da produção de adultos, nas duas concentrações, ao longo das gerações, mas apenas no experimento a 200 µg/ml os dados foram estatisticamente significantes. Quanto à oviposição, a análise dos números mostra redução crescente e acentuada na média de ovos por fêmea, no experimento tratado. CONCLUSÕES: Não houve evidência de resistência ao longo das gerações devido ao tratamento com cafeína. Os resultados encontrados podem reforçar a indicação da cafeína como uma alternativa aos principais agentes de controle do Ae. aegypti atualmente usados, contra os quais os mosquitos têm desenvolvido resistência.

Deposição eletrolítica catódica e anódica simultâneas para minimizar interferências de cobre e chumbo na determinação espectrofotométrica de cádmio em água e alimentos via reação com Verde de Malaquita e iodeto

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Construção de pilhas elétricas simples: Um experimento integrado de química e física

Neste artigo são descritas formas simples e de baixo custo de se montar pilhas, empregando-se placas de zinco, magnésio e cobre mergulhadas diretamente nas soluções eletrolíticas. Como soluções eletrolíticas podem ser empregadas suco de frutas cítricas, ou mesmo apenas água de torneira. A tensão e corrente produzidas pelas pilhas montadas são suficientes para acionar dispositivos com baixa demanda de potência, como relógios analógicos e digitais . Os experimentos podem ser explorados como simples demonstração de transformação de energia química em elétrica para alunos do nível fundamental, ou utilizados como práticas interdisciplinares de Física e Química para alunos mais avançados.

Determinação do ponto de colheita e indução à abertura floral do crisântemo cultivar White Polaris em diferentes concentrações de sacarose

Realizou-se pesquisa objetivando determinar o melhor entre quatro pontos de colheita da haste floral de crisântemos de maço do tipo pompom cv. White Polaris a concentração mais adequada de sacarose para tratamento de pulsing dessas hastes: estas foram colhidas em estufa de produção comercial, nos pontos preestabelecidos e transportadas para laboratório, onde foram totalmente imersas em água de torneira, à sombra, durante três horas. Selecionaram-se as hastes pela uniformidade do seu desenvolvimento e cortaram-nas sob água na base do caule, entre 50 e 60 cm, e identificadas, o que permitiu avaliar as mudanças morfológicas associadas às inflorescências individuais. As hastes foram distribuídas e mantidas nos diferentes tratamentos de pulsing durante 24 horas, à luz branca contínua de 1.500 lux, 60 a 90% de umidade relativa do ar e temperatura ambiente de 25 ± 2°C. Após o tratamento de pulsing, as hastes foram transferidas para água destilada, permanecendo por 10 horas sob luz branca contínua, nas mesmas condições de laboratório citadas. A vida floral em vaso começou a ser avaliada na instalação do experimento, após o tratamento de pulsing, e terminou quando as folhas e pétalas perderam a turgescência e o valor decorativo. As hastes colhidas em estádio de botão (25 e 50% de abertura das inflorescências apicais) não alcançaram o ponto de abertura adequado em nenhuma das seis concentrações de sacarose (0 a 146,07 mol/m³); as concentrações de 116,9 146,1 mol/m³, porém, estimularam, em geral, a abertura de botões. Os pontos de colheita 1 e 2 (100 e 75% de abertura das inflorescências apicais respectivamente) apresentaram bons resultados em todas as concentrações de sacarose.

Manutenção da qualidade e aumento da longevidade floral de crisântemo cv. White polaris

0 objetivo do trabalho foi determinar o melhor tratamento pós-colheita para manutenção floral e aumento da longevidade de crisântemo de maço do tipo pompom (Dendranthema grandiflorum (Ramat.) S. Kitamura) cv. White Polaris. Estabeleceu-se como ponto de colheita o momento em que as hastes apresentavam três inflorescências apicais com as pétalas externas em ângulo de 45° em relação à horizontal. Durante o ensaio em laboratório, as hastes, colhidas em estufa de produção comercial, após totalmente imersas em água de torneira, à sombra, durante três horas, foram cortadas sob água na base do caule entre 50 e 60 cm. As hastes foram distribuídas nos diferentes tratamentos de pulsing durante 24 horas, com luz contínua de 1.500 lux, 60 a 90% de umidade relativa do ar e temperatura ambiente de 25 ± 2°C. No primeiro experimento, testou-se a eficiência de 8-hidroxiquinolina (8-HQ) e tiabendazole (TBZ) como germicidas de manutenção da qualidade na solução de pulsing; testaram-se, também, dois reguladores de crescimento, a saber: ácido giberélico (GA3), 6-benzilaminopurina (6-BA) ou a mistura dos dois, com o objetivo de preservar a cor e a turgidez da folhagem. Os melhores resultados foram com 8-HQ (0,69 mol/m³) e GA3 (0,058 mo1/m³). No segundo experimento, avaliaram-se os seguintes inibidores de etileno: tiossulfato de prata (STS), nitrato de prata (AgNO3) e cloreto de cobalto (COC1(2)). A melhor resposta foi obtida com AgNO3 (2,9 e 4,4 mo1/m³).

Adhesives with different pHs: Effect on the MTBS of chemically activated and light-activated composites to human dentin

Purpose: To evaluate the bond strength between human dentin and composites, using two light-activated single-bottle total-etch adhesive systems with different pHs combined with chemically activated and light-activated-composites. The tested hypothesis was that the dentin bond strength is not influenced by an adhesive system of low pH, combined with chemically activated or light-activated composites. Material and Method: Flat dentin surfaces of twenty-eight human third molars were allocated in 4 groups (n=7), depending on the adhesive system: (One Step Plus-OS and Prime & Bond NT-PB) and composite (light-activated Filtek Z-100 [Z100] and chemically activated Bisfil 2B [B2B]). Each adhesive system was applied on acid-etched dentin and then one of the composites was added to form a 5 mm-high resin block. The specimens were stored in tap water (37 degrees C/24 h) and sectioned into two axes, x and y. This was done with a diamond disk under coolant irrigation to obtain beams with a cross-section area of approximately 0.8 mm(2). Each specimen was then attached to a custom-made device and submitted to the microtensile test (1 mm.min(-1)). Data were analyzed using two-way ANOVA and Tukey's tests (p<0.05). Results: the anticipated hypothesis was not confirmed (p<0.0001). The bond strengths (MPa) were not statistically different between the two adhesive systems when light-activated composite was used (OS+Z100 = 24.7 +/- 7.1(a); PB+Z100 = 23.8 +/- 5.7(a)). However, with use of the chemically activated composite (B2B), PB (7.8 +/- 3.6(b) MPa) showed significantly lower dentin bond strengths than OS (32.2 +/- 7.6(a)). Conclusion: the low pH of the adhesive system can affect the bond of chemically activated composite to dentin. on the other hand, under the present conditions, the low pH did not seem to affect the bond of light-activated composites to dentin significantly.

Toxic effects of alcohol intake on prostate of rats

BACKGROUND. The present report was carried out to determine whether alcohol intake could induce prostate lesions.METHODS. We tested male rats for 300 days. Animals were divided into three groups: controls received only tap water as liquid diet; the chronic alcohol intake group received only ethanol solution in semivoluntary research; and the withdrawal group received the same treatment as chronic alcohol intake until 240 days, after which they reverted to drinking water.RESULTS. Chronic alcohol intake increased lipoperoxide concentrations and acid phosphatase activities. Cu-Zn superoxide dismutase (SOD) was decreased at 60 days, but approached controls values at 300 days following treatment. The serum increased alkaline phosphatase, and alanine transaminase activities reflected the chronic toxic effect of ethanol.CONCLUSIONS. Since SOD activity was unable to scavenge superoxide radical and lipoperoxide formation, we can conclude that superoxide is an important intermediate in prostate damage of chronic alcohol intake. (C) 1997 Wiley-Liss, Inc.

Electrochemical reduction and determination of Cibacron Blue F3GA at poly-L-lysine modified glassy carbon electrode

The oxidation of a reactive dye, Cibacron Blue F3GA, CB, (C.I. 61211), widely used in the textile industries to color natural fibers, was studied by electrochemical techniques. The oxidation on glassy carbon electrode occurs in two steps at 2.0 < pH < 10 involving one electron transfer each to the amine group leading to the imide derivative. Stable films of poly-L-lysine (PLL) in the presence of glutaraldehyde (GA) 97.5%:2.5% on glassy carbon electrode can be used to detect low levels of dye using its oxidation peak at +0.75V by voltammetry. Linear calibration graphs were obtained for the CB reactive dye, from 1.0 X 10(-6) to 1.0 X 10(-5) mol L-1 in B-R buffer, pH 2.0, using a pre-concentration off-line during 10 min. The detection limit (3 sigma/slope) was calculated to be 4.5 X 10(-8) mol L-1. Films of PLL can readily be applied for the determination of CB dye bearing aminoanthraquinone as chromophore and chlorotriazinyl as reactive group at concentrations at least 100 times lesser than using a glassy carbon electrode without modification. The method described was applied for the determination of CB dye in tap water and raw water collected from the municipal treatment plant with a recovery of 89.2% +/- 5.4 and 88.0% +/- 6.5, respectively. (c) 2005 Elsevier Ltd. All rights reserved.

Experimental alcoholism and pathogenesis of prostatic diseases in UChB rats

Previous studies have shown that long-term alcohol treatment has negative effects on prostatic stromal-epithelial interaction. Thus, the aim of the present study was to analyze the histochemical, immunohistochemical and ultrastructural alterations that occur in the prostatic stroma and epithelium of rats submitted to chronic alcohol ingestion and alcohol abstinence, as well as to establish the relationship between these changes and prostatic diseases. Thirty male rats (10 Wistar and 20 UChB rats) were divided into three experimental groups: the control group received tap water, the alcoholic group received ethanol diluted to 10 degrees G.L. for 150 days, and the abstinent group received the same liquid diet as the alcoholic group up to 120 days of treatment and only tap water for 30 days thereafter. At the end of treatment, all animals were sacrificed and the ventral lobe of the prostate was removed and processed for histochemical, immunohistochemical and ultrastructural analyses. In addition, plasma testosterone levels were measured. The results showed, prostatic intraepithelial neoplasia, infolding of the epithelium towards the stroma, stromal hypertrophy and the presence of inflammatory cells in alcoholic animals. In the abstinent group, alterations were noted mainly in the stromal area. In conclusion, ethanol triggers alterations in prostatic epithelial and stromal compartments, affecting the stromal microenvironment and predisposing the organ to pathological processes. (C) 2006 International Federation for Cell Biology. Published by Elsevier Ltd. All rights reserved.

Compact disks, a new source for gold electrodes. Application to the quantification of copper by PSA

In this work we describe a versatile and very sensitive way for copper quantification by potentiometric stripping analysis using gold electrodes obtained from recordable compact disks (CDs). This new source of electrodes (CDtrodes) shown similar performance to the commercial gold electrodes with superior versatility and lower cost. Recordable CDs contains a highly pure gold film with thickness between 50 and 100 nm and superficial area of ca. 100 cm(2). The working electrode developed was used successfully in stationary cell and many experimental parameters have been optimized. For copper, the detection limit attained was 30 ng L-1 (600 s deposition time) with remarkable precision (standard deviation of 1.8 % for 20 repetitive measurements using 25 mu gL(-1) of copper with 60 s of deposition time). The gold electrode developed was used for analysis of copper in sugar cane spirits and tap water samples. The results were compared with those obtained by atomic absorption spectroscopy.

Toxicity of chronic ethanol ingestion and superoxide radical formation on seminal vesicles of rats

The toxic effects of chronic ethanol ingestion were evaluated in male adult rats for 300 days. The animals were divided into three groups: the controls received only tap water as liquid diet; the chronic ethanol ingestion group received only ethanol solution (30%) in semivoluntary research; and the withdrawal group received the same treatment as chronic ethanol-treated rats until 240 days, after which they reverted to drinking water. Chronic ethanol ingestion induced increased lipoperoxide levels and acid phosphatase activities in seminal vesicles. Cu-Zn superoxide dismutase (SOD) decreased from its basal level 70.8 +/- 3.5 to 50.4 +/- 1.6 U/mg protein at 60 days of chronic ethanol ingestion. As changes in GSH-PX activity were observed in rats after chronic ethanol ingestion, while SOD activities were decreased in these animals, it is assumed that superoxide anion elicits lipoperoxide formation and induces cell damage before being converted to hydrogen peroxide by SOD. Ethanol withdrawal induced increased SOD activity and reduced seminar vesicle damage, indicating that the toxic effects were reversible, since increased SOD activity was adequate to scavenge superoxide radical formation. Superoxide radical is an important intermediate in the toxicity of chronic ethanol ingestion. Copyright (C) 1996 Elsevier B.V. Ltd

Evidence of thermostable amylolytic activity from Rhizopus microsporus var. rhizopodiformis using wheat bran and corncob as alternative carbon source

Rhizopus microsporus var. rhizopodiformis produced high levels of alpha-amylase and glucoamylase under solid state fermentation, with several agricultural residues, such as wheat bran, cassava flour, sugar cane bagasse, rice straw, corncob and crushed corncob as carbon sources. These materials were humidified with distilled water, tap water, or saline solutions-Segato Rizzatti (SR), Khanna or Vogel. The best substrate for amylase production was wheat bran with SR saline solution (1:2 v/v). Amylolytic activity was still improved (14.3%) with a mixture of wheat bran, corncob, starch and SR saline solution (1:1:0.3:4.6 w/w/w/v). The optimized culture conditions were initial pH 5, at 45 degrees C during 6 days and relative humidity around 76%. The crude extract exhibited temperature and pH optima around 65 degrees C and 4-5, respectively. Amylase activity was fully stable for 1 h at temperatures up to 75 degrees C, and at pH values between 2.5 and 7.5.

Fetal and maternal lesions of cyanide dosing to pregnant goats

The present work evaluated the pathological effects in both dams and their fetuses of cyanide ingestion during pregnancy using goat as animal model. From the Day 24 of pregnancy, three pregnant goats were dosed by gavage with 3.0 mg KCN/kg bw/day, and two others received only tap water. All dams were euthanized and necropsied at Day 120 of pregnancy. The fetuses were examined carefully for gross abnormalities. Determinations of cyanide and thiocyanate were performed in maternal and fetal blood and in amniotic fluid. Samples of several organs were collected for histopathologic evaluation. No clinical changes were seen in any animal throughout the pregnancy. No malformations or dead fetuses were observed: however, placenta from one treated goat presented increased cotyledon surface area occupied by vascular lumina. Histological lesions in KCN-treated dams consisted of vacuolation of hepatocytes and thyroid follicular cells, increased number of vacuoles on thyroid follicular colloid. and spongiosis of cerebral, internal capsule, and cerebellar peduncles tracts. Fetuses from these mothers showed vacuolation of hepatocytes and thyroid follicular cells, and spheroids in the cerebellar white matter. Levels of cyanide and thiocyanate were higher in maternal than fetal blood, which suggests that these substances were largely but not freely transferred from mothers to fetuses. (C) 2009 Elsevier B.V. All rights reserved.