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.

Effect of water renewal on dominance hierarchy of juvenile Nile tilapia

RECAW - CNPq

Effect of photodynamic therapy on clinical isolates of Staphylococcus spp

Staphylococcus spp. are opportunistic microorganisms known for their capacity to develop resistance against antimicrobial agents. The objective of this study was to evaluate the effect of photodynamic therapy (PDT) on 20 Staphylococcus strains isolated from the human oral cavity, including S. aureus, S. schleiferi, S. epidermidis, S. capitis, S. haemolyticus, and S. lentus. A suspension of each Staphylococcus strain (10(6) cells/mL) was submitted to PDT using methylene blue and a low power laser. The isolated effects of methylene blue, laser treatment and ciprofloxacin were also evaluated. After the experimental treatments, 0.1 mL aliquots of the suspensions were seeded onto BHI agar for determination of the number of colony-forming units (CFU/mL). The results were analyzed by analysis of variance and Tukey's test (p < 0.05). The mean reduction in bacterial counts of the strains submitted to PDT ranged from 4.89 to 6.83 CFU (log10)/mL, with the observation of a decreasing susceptibility to treatment of S. schleiferi, S. haemolyticus, S. epidermidis, S. capitis, S. aureus, and S. lentus. The results showed that PDT was effective in reducing the number of viable cells of all clinical Staphylococcus isolates studied.

Effect of estrogen therapy, soy isoflavones, and the combination therapy on the submandibular gland of ovariectomized rats

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

Effect of low-calcium diet and grind diet on bone turnover of ovariectomized female rats

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

In vitro study of the Nd : YAG laser effect on human dental enamel: Optical and scanning electron microscope analysis

Objective: the Nd:YAG laser irradiation of dental enamel was evaluated in enamel demineralization experiments in a Streptococcus mutans culture media. Summary Background Data: Previous studies had shown that a continuous wave Nd:YAG laser at an energy of approximately 67 mJ may induce an increased acid resistance in human dental enamel when exposed to severe demineralization conditions. Methods: Enamel windows of 3 x 4 cm in the buccal surface were irradiated with a continuous wave Nd:YAG laser at a wavelength of 1,064 Ecm using energy densities of from 83.75 to 187.50 J/cm(2), Enamel windows of 3 x 4 cm on the lingual surface served as control (without the laser irradiation). The enamel windows were then exposed to a Streptococcus mutans culture media at a temperature of 37 degrees C for 15 and 21 days. The laser effects and demineralization were examined both by optical microscopy and scanning electron microscopy (SEM), Results: A comparison between the lased and the unlased windows of enamel showed fusion and recrystalization of the enamel and increased acid-resistance in all groups irradiated with the Nd:YAG laser, on the other hand, the 3 x 4 delimited enamel surfaces from the control group (not irradiated with the Nd:YAG laser) showed 100% deminerization, Conclusions: These findings are consistent with the finding that laser irradiation of dental results in significant reduction of the effective solubility of enamel mineral.

A note on the attenuation of the sommerfeld effect of a non-ideal system taking into account a MR damper and the complete model of a DC motor

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of annealing time on morphological characteristics of Ba(Zr,Ti)O-3 thin films

Ba(Zr0.50Ti0.50)O-3 thin films were prepared by the polymeric precursor method using the annealing low temperature of 300 degrees C for 8, 16, 24, 48, 96 and 192 It in a furnace tube with oxygen atmosphere. The X-ray diffraction patterns revealed that the film annealed for 192 h presented some crystallographic planes (1 0 0), (1 1 0) and (2 0 0) in its crystalline lattice. Fourier transformed infrared presented the formation of metal-oxygen stretching at around 756 cm(-1). The atomic force microscopy analysis presented the growth of granules in the Ba(Zr0.50Ti0.50)O-3 films annealed from 8 to 96 h. The crystalline film annealed for 192 h already presents grains in its perovskite structure. It evidenced a reduction in the thickness of the thin films with the increase of the annealing time. (C) 2006 Elsevier B.V. All rights reserved.

Well-Alloyed PtFe/C Nanocatalysts of Controlled Composition and Same Particle Size: Oxygen Reduction and Methanol Tolerance

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

Chlorination treatment of aqueous samples reduces, but does not eliminate, the mutagenic effect of the azo dyes Disperse Red 1, Disperse Red 13 and Disperse Orange 1

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

Preparation and bactericidal effect of composites based on crosslinked copolymers containing silver nanoparticles

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of lactic acid and UV irradiation on the cassava and corn starches

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

Effect of addition of different hydrocolloids on pasting, thermal, and rheological properties of cassava starch

Amidos e gomas são hidrocoloides frequentemente usados em sistemas alimentícios com a finalidade de fornecer textura, umidade e mobilidade de água. A interação amido-goma em sistemas alimentícios pode alterar o inchamento do grânulo de amido e as suas propriedades de gelatinização e reológicas. Neste trabalho, o efeito da adição de goma xantana (GX), carboximetilcelulose sódica (CMC) e carragena (CAR) nas concentrações de 0,15, 0,25, 0,35 e 0,45% (p/v) sobre as propriedades de pasta, térmicas e reológicas do amido de mandioca foi estudado. O Poder de inchamento (PI) e a Microscopia Eletrônica de Varredura (MEV) dos géis de amido também foram avaliados. Os resultados obtidos mostraram que a GX apresentou forte interação com o amido, penetrando entre os grânulos e provocando aumento das viscosidades de pasta, PI, G' e G, e redução da retrogradação do amido; CMCS aumentou as viscosidades de pasta, PI, G' e G das misturas, principalmente em função da sua maior capacidade de reter água, e não por causa da interação com o amido; CAR não modificou qualquer das propriedades do amido, porque não houve nenhuma interação entre essa goma e o amido de mandioca nas concentrações usadas.

Manipulation of fire ant density, Solenopsis spp., for short-term reduction of Diatraea saccharalis larval densities in Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of an experimental 4% titanium tetrafluoride varnish on dental erosion by a soft drink

Objectives: This in vitro study assessed the effect of an experimental 4%TiF4 varnish on enamel erosion.Methods: Sixty bovine enamel blocks were randomly allocated to each type of varnish:Duraphat((R)) -D (NaF, 2.26%F), Duofluorid((R))-F(NaF, 2.71% F), TiF4-T(2.45%F) and no-fluoride-P. After application of the varnishes, the blocks were subjected to six sequential pH cycles (cola drink for 10 min and artificial saliva for 50 min, each) per day, during 4 days. After the pH cycles, the blocks were maintained in artificial saliva for 18 h. Enamel alterations were determined in the 2nd and 4th days, using profilometry (wear) and microhardness (%SMHC) tests. Data were tested using ANOVA and Tukey's tests (p < 0.05).Results: the mean %SMHC (+/- S.D.) at the 2nd and 4th day was, respectively, D (-77.26 +/- 5.04(a) and -88.59 +/- 5.11(A)), F (-76.79 +/- 7.82(a) and -88.78 +/- 6.10(A)), T(-88.28 +/- 3.19(b) and -92.04 +/- 2.54(A,B)) and P (-87.96 +/- 2.23(b) and -94.15 +/- 1.14(B)). The mean wear (mu m +/- S.D.) at the 2nd and 4th day was, respectively, D (3.16 +/- 0.32(a) and 7.56 +/- 0.90(A)), F(3.35 +/- 0.78(a,b) and 7.92 +/- 0.98(A)), T (3.81 +/- 0.43(b) and 7.69 +/- 0.76(A)) and P (3.43 +/- 1.13(a,b) and 7.31 +/- 0.53(A)).Conclusions: the NaF varnishes reduced the softening, but had no effect on the reduction of the wear. The TiF4 varnish was not able to reduce the softening and wear. (C) 2007 Elsevier Ltd. All rights reserved.