Characterization of metallic electrical contacts to SnO2 thin films lightly doped with Eu3+ ions, and photo-induced resistivity

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Photo-Induced Dipole Relaxation Current in Natural Amethyst

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

On line extraction and separation of bendiocarb, methomyl, methylparathion, and pentachlorophenol pesticides from raw milk

A high performance liquid chromatography (HPLC) method for extraction and determination of pesticides from raw milk was developed. The method involves direct injection of raw milk samples on a bovine serum albumin-dimethyl-octyl-silica gel (BSA-Si-Cs) column. The mobile phase 0.05 mol.L-1 phosphate buffer pH6.0 in acetonitrile (70:30 v/v) was employed for extraction and separation of bendiocarb, methylparathion, pentachlorophenol, and methomyl pesticides. The method shows good results of recovery in the pesticides studied, higher than 99.6%.

The influence of visual inter-hemispheric connections on spiking, assembly and LFP activities, and their phase relationship during figure-ground stimulation

Desde os descobrimentos pioneiros de Hubel e Wiesel acumulou-se uma vasta literatura descrevendo as respostas neuronais do córtex visual primário (V1) a diferentes estímulos visuais. Estes estímulos consistem principalmente em barras em movimento, pontos ou grades, que são úteis para explorar as respostas dentro do campo receptivo clássico (CRF do inglês classical receptive field) a características básicas dos estímulos visuais como a orientação, direção de movimento, contraste, entre outras. Entretanto, nas últimas duas décadas, tornou-se cada vez mais evidente que a atividade de neurônios em V1 pode ser modulada por estímulos fora do CRF. Desta forma, áreas visuais primárias poderiam estar envolvidas em funções visuais mais complexas como, por exemplo, a separação de um objeto ou figura do seu fundo (segregação figura-fundo) e assume-se que as conexões intrínsecas de longo alcance em V1, assim como as conexões de áreas visuais superiores, estão ativamente envolvidas neste processo. Sua possível função foi inferida a partir da análise das variações das respostas induzidas por um estímulo localizado fora do CRF de neurônios individuais. Mesmo sendo muito provável que estas conexões tenham também um impacto tanto na atividade conjunta de neurônios envolvidos no processamento da figura quanto no potencial de campo, estas questões permanecem pouco estudadas. Visando examinar a modulação do contexto visual nessas atividades, coletamos potenciais de ação e potenciais de campo em paralelo de até 48 eletrodos implantados na área visual primária de gatos anestesiados. Estimulamos com grades compostas e cenas naturais, focando-nos na atividade de neurônios cujo CRF estava situado na figura. Da mesma forma, visando examinar a influência das conexões laterais, o sinal proveniente da área visual isotópica e contralateral foi removido através da desativação reversível por resfriamento. Fizemos isso devido a: i) as conexões laterais intrínsecas não podem ser facilmente manipuladas sem afetar diretamente os sinais que estão sendo medidos, ii) as conexões inter-hemisféricas compartilham as principais características anatômicas com a rede lateral intrínseca e podem ser vistas como uma continuação funcional das mesmas entre os dois hemisférios e iii) o resfriamento desativa as conexões de forma causal e reversível, silenciando temporariamente seu sinal, permitindo conclusões diretas a respeito da sua contribuição. Nossos resultados demonstram que o mecanismo de segmentação figurafundo se reflete nas taxas de disparo de neurônios individuais, assim como na potência do potencial de campo e na relação entre sua fase e os padrões de disparo produzidos pela população. Além disso, as conexões laterais inter-hemisféricas modulam estas variáveis dependendo da estimulação feita fora do CRF. Observamos também uma influência deste circuito lateral na coerência entre potenciais de campo entre eletrodos distantes. Em conclusão, nossos resultados dão suporte à ideia de um mecanismo complexo de segmentação figura-fundo atuando desde as áreas visuais primárias em diferentes escalas de frequência. Esse mecanismo parece envolver grupos de neurônios ativos sincronicamente e dependentes da fase do potencial de campo. Nossos resultados também são compatíveis com a hipótese que conexões laterais de longo alcance também fazem parte deste mecanismo

High-performance liquid chromatographic separation and identification of polyphenolic compounds from the infusion of Davilla elliptica St. Hill

The isolation of polyphenolic compounds from an infusion of the Brazilian plant Davilla elliptica (Dilleniaceae), used as tea by virtue of its digestive properties, is described. An improved preparative HPLC method was used in order to isolate pure polyphenols from the complex mixture. Liquid-liquid extraction and solid-phase extraction were employed to minimise the interference of polymeric compounds and to provide an enriched fraction of the compounds of interest. The identification of the isolated compounds was performed using analytical HPLC as well as direct injection electrospray ionisation ion trap tandem mass spectrometry (ESI-IT-MS/MS). The high flavonoid content suggests that D. elliptica may be a promising source of compounds to produce natural phytomedicines. Copyright (C) 2007 John Wiley & Sons, Ltd.

Induced crystallization on tellurite 20Li(2)O-80TeO(2) glass

Crystallization kinetics and structure of 20Li(2)O-80TeO(2) glasses are studied using x-ray diffraction, Fourier transform infrared spectroscopy and differential scanning calorimetry techniques. XRD results show gamma-TeO2, alpha-TeO2 and Li2Te2O5 phase crystallization in the glass matrix. The infrared band structure of this glass is similar to that observed in glassy TeO2. Activation energies were evaluated from Lorentzian three-peak deconvolution of the DSC crystallization peak recorded at different particle sizes. As the obtained activation values were very close, it was not possible to establish a hierarchy on the crystallization of this glass. In addition, the height of the Lorentzian peaks ( delta T-P1, delta T-P2 and delta T-P3) for each sample was measured and plotted against the nucleation temperature. The presence of two maxima at around 284 and 304 degrees C suggests at least two maximum nucleation temperatures in the studied 20Li(2)O-80TeO(2) glass.

Thermally stimulated crystallization glass system of (20-x)LiO2-80TeO(2)-xWO(3)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

No mutations found in exon 2 of gene p16CDKN2A during rat tongue carcinogenesis induced by 4-nitroquinoline-1-oxide

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

Cytokines and acute-phase serum proteins as markers of inflammatory regression during pulmonary tuberculosis treatment

Tuberculosis is still increasing and was declared a worldwide sanitary emergency by the World Health Organization (WHO) in 1995. Its control is difficult due to long treatment duration and lack of markers of treatment success or failure. Cytokines such as IFN-gamma and TNF-alpha, a central factor in immune response against Mycobacterium tuberculosis, are responsible for the interaction between T lymphocytes and the infected macrophage and are also produced during this interaction. As proinflammatory cytokines have a close relationship with mycobacteria clearance, in fact even preceding it, they could be used as markers for inflammatory activity and response to treatment. Proinflammatory cytokines act in the liver and stimulate a strong local and systemic acute-phase response as a result of homeostatic and physiological responses also induced by them. Acute-phase proteins produced by cytokine activity are useful diagnostic markers that could also be used to monitor treatment response as they can be serially quantified. The objective of this study was to evaluate IFN-gamma, TNF-alpha, IL-10 and TGF-beta production in supernatant of peripheral blood mononuclear cell (PBMC) and monocyte (MO) cultures, as well as serum acute-phase response through total protein, albumin, globulin, C-reactive protein (CRP), alpha-1-acid glycoprotein (AGP), and erythrocyte sedimentation rate (ESR) as regression markers of inflammatory response during pulmonary tuberculosis treatment. Twenty blood donors (G1) from the Blood Bank at Botucatu School of Medicine's University Hospital (BSM-UH) were evaluated once and 28 pulmonary tuberculosis patients (G2): 13 from BSM-UH and 15 from the Bauru State Health Secretariat. Patients were evaluated at three moments of treatment: before (M1), at three months (M2), and at the end (M3). Cytokines were determined in 20ml of peripheral blood (ELISA), with or without activation: lipopolysaccharide (LPS) for MO culture and phytohemagglutinin (PHA) for PBMC culture. Acute-phase protein behavior in G2 throughout treatment was: Globulins: M1> M2, M1> M3 (rho < 0.001); CRP: M1> M2> M3 (.< 0.001); AGP for men: M1> M2, M1> M3 (rho < 0.001); ESR for men: M1> M2, M1> M3 (rho < 0.0016) and for women: M1> M2 (.< 0.025). Comparison between cytokine levels found in supernatant of MO and PBMC cultures, with and without stimulus, in G1 and G2 during treatment showed: TNF-alpha (with/ without LPS) at M1: G2> G1; at M2: G2> G1 (rho < 0.001); (without LPS) at M3: G2> G1 (rho < 0.001), (with LPS) at M3: G2> G1 (rho < 0.028); IFN-. (with and without PHA) at M1: G2> G1; at M2: G2> G1 (rho < 0.001); IL-10 (with and without LPS) at M1: G2> G1; at M2: G2> G1; at M3: G2> G1 (rho < 0.001); TGF-beta (with and without LPS) at M1: G2> G1; at M2: G2> G1 (rho < 0.001), (without LPS) at M3: G2> G1 (rho < 0.001). In G2, all cytokines in supernatant of MO and PBMC cultures, with and without stimulus, showed: M1> M2> M3 (rho < 0.01). Levels of globulins, CRP, AGP, and ESR in patients with pulmonary tuberculosis before treatment (M1) were significantly higher than reference values, suggesting their use as diagnostic markers and indicators of treatment. The CRP decreasing values along treatment could be taken as a marker of the regression of inflammatory process and of response to treatment in patients with pulmonary tuberculosis.Regarding cytokines, there was significant increase in TNF-alpha, IFN-gamma, IL-10, and TGF-alpha levels before and at three months treatment, with and without stimulus; in TNF-a and IL-10 lvels, with and without stimulus, as well as in TGF-alpha levels without stimulus at six months. Patients had higher levels of all studied cytokines than controls before treatment, and these values decreased along treatment. In this study, pulmonary tuberculosis patients showed a Th0 cytokine profile before treatment, with the production of both Th1 (IFN-gamma) and Th2 (IL-10) cytokines, in addition to TNF-alpha inflammatory and TGF-alpha regulatory and fibrosis-inducer cytokines. At the end of treatment, all had evolved to Th2 profile, probably in an attempt to reduce the harmful effects of the proinflammatory activity of the Th1 cytokine profile and of the still above-normal levels of TNF-alpha. The high levels of TGF-alpha, also found in these patients, are related to its important role in the extracellular matrix deposition and fibrosis induction that characterize tuberculosis healing process. IFN-gamma was the only cytokine reaching normal levels at the end of treatment, which suggests its use as a marker of response to treatment.

Effect of lycopene on doxorubicin-induced cardiotoxicity: An echocardiographic, histological and morphometrical assessment

Doxorubicin is an excellent chemotherapeutic agent utilized for several types of cancer but the irreversible doxorubicin-induced cardiac damage is the major limitation for its use. Oxidative stress seems to be associated with some phase of the toxicity mechanism process. To determine if lycopene protects against doxorubicin-induced cardiotoxicity, male Wistar rats were randomly assigned either to control, lycopene, doxorubicin or doxorubicin + lycopene groups. They received corn oil (control, doxorubicin) or lycopene (5 mg/kg body weight a day) (lycopene, doxorubicin + lycopene) by gavage for a 7-week period. They also received saline (control, lycopene) or doxorubicin (4 mg/kg) (doxorubicin, doxorubin + lycopene) intraperitoneally by week 3, 4 5 and 6. Animals underwent echocardiogram and were killed for tissue analyses by week 7. Mean lycopene levels (nmol/kg) in liver were higher in the doxorubicin + lycopene group (5822.59) than in the lycopene group (2496.73), but no differences in lycopene were found in heart or Plasma of these two groups. Lycopene did not prevent left ventricular systolic dysfunction induced by doxorubicin. However, morphologic examination revealed that doxorubicin-induced myocyte damage was significantly suppressed in rats treated with lycopene. Doxorubicin treatment was followed by increase of myocardium interstitial collagen volume fraction. Our results show that: (i) doxorubicin-induced cardiotoxicity was confirmed by echocardiogram and morphological evaluations; (ii) lycopene absorption was confirmed by its levels in heart, liver and plasma; (iii) lycopene supplementation provided myocyte protection without preventing interstitial collagen accumulation increase; (iv) doxorubicin-induced cardiac dysfunction was not prevented by lycopene supplementation; and (v) lycopene depletion was not observed in plasma and tissues from animals treated with doxorubicin.

Coffee and Caffeine Protect against Liver Injury Induced by Thioacetamide in Male Wistar Rats

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

Mate attenuates DNA damage and carcinogenesis induced by diethylnitrosamine and thermal injury in rat esophagus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The role of the TP53 gene during rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide

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

Follicular Development in Ewes During Natural and Prostaglandins Induced Estrous Cycle

The follicular development was evaluated in ovine females during natural and prostaglandin-F(2 alpha) (PG) induced estrous cycle. Ewes were randomly divided in two treatments (n=7/treatment): T1 with natural cycle and T2 synchronized with two injections of PG. From one day before PG injection until next ovulation, daily transrectal ultrasonography was done. All follicles >= 2 mm were assessed. During the interovulatory intervals, follicular growth and regression occurred in a wave like pattern (2-3 waves). The maximum diameter of the largest follicle of the first wave was greater in T1 (5.83 +/- 0.31 mm) compared with T2 (5.0 +/- 0.1 mm; P<0.01), but there was no significant difference among the emergency day of largest follicle, during the growth phase of the follicular waves. The duration of the plateau phase in wave 2 differed between the two treatments (P<0.05) showing 0.83 +/- 0.31 and 1.83 +/- 0.17 d, for natural and synchronized treatment, respectively. Growth rate did not differ between treatments. Presence of new luteal tissue was detected on day 3 after ovulation. In conclusion, the follicular development was similar in female ovine during natural and PG induced estrous cycle.

Water deprivation-induced sodium appetite

A water deprived animal that ingests only water efficiently corrects its intracellular dehydration, but remains hypovolemic, in negative sodium balance, and with high plasma renin activity and angiotensin II. Therefore, it is not surprising that it also ingests sodium. However, separation between thirst and sodium appetite is necessary to use water deprivation as a method to understand the mechanisms subserving sodium appetite. For this purpose, we may use the water deprivation-partial repletion protocol, or WD-PR. This protocol allows performing a sodium appetite test after the rat has quenched its thirst; thus, the sodium intake during this test cannot be confounded with a response to thirst. This is confirmed by hedonic shift and selective ingestion of sodium solutions in the sodium appetite test that follows a WD-PR. The separation between thirst and sodium appetite induced by water deprivation permits the identification of brain states associated with sodium intake in the appetite test. One of these states relates to the activation of angiotensin II All receptors. Other states relate to cell activity in key areas, e.g. subfornical organ and central amygdala, as revealed by immediate early gene c-Fos immunoreactivity or focal lesions. Angiotensin II apparently sensitizes the brain of the water deprived rat to produce an enhanced sodium intake, as that expressed by spontaneously hypertensive and by young normotensive rat. The enhancement in sodium intake produced by history of water deprivation is perhaps a clue to understand the putative salt addiction in humans.The paper represents an invited review by a symposium, award winner or keynote speaker at the Society for the Study of Ingestive Behavior [SSIB] Annual Meeting in Portland, July 2009. (C) 2010 Published by Elsevier B.V.