Reversed phase HPLC determination of zidovudine in rat plasma and its pharmacokinetics after a single intranasal dose administration

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

Development and validation of HPLC method for analysis of dexamethasone acetate in microemulsions

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Associação entre polimorfismos funcionais nos genes da MMP-7 e MMP-9 e o perfil clinicopatológico do carcinoma epidermóide de língua

Matrix metalloproteinase-7 (MMP-7) and -9 (MMP-9) modulate important functions strictly related to the development, invasion and metastasis of several human cancers among them the squamous cell carcinoma of the tongue (SCCT). However, individual genetic factors such as the functional single nucleotide polymorphisms (SNPs) influence the pattern of protein expression of these MMPs and thus may be related to the variability observed in the clinical behavior of patients with SCCT. In this context, the present cross-sectional study aimed to evaluate the association between the frequency of the functional SNPs MMP-7 -181 A/G and MMP-9 -1562 C/T and the clinical (age, gender and metastasis) and pathological (malignancy histological grading and immunohistochemistry expression) features of SCCT cases. Genotyping of these SNPs were performed by PCR-RFLP on DNA samples from 71 cases of SCCT and 60 individuals without cancer who constitute the control group. Among the results of this research, it was observed that the frequency of the polymorphic alleles MMP-7 -181 G and MMP-9 -1562 T in SCCT patients was 28% and 12%, respectively, and the frequency of the heterozygotes A/G (PR = 2.00; p < 0.001) and C/T (PR = 1.54; p = 0.014) were significantly higher in the patient group than in the controls. The prevalence of patients carrying the combination of SNPs studied was significantly associated with SCCT cases (PR = 2.00; p = 0.011) and metastasis (PR = 2.00; p < 0.001). Furthermore, with the frequency of SNPs analyzed, the age, gender, histological grading and immunoreactivity of MMP-7 and MMP-9 formed clinical and pathological parameters relevant to the identification of population subgroups more related to the development of SCCT and metastasis. Based on these results, it is suggested that the protein expression levels of MMP-7 and -9 substantially influence the balance between their pro- and anticancer biological functions and hence the clinicopathological profile of the squamous cell carcinoma of the tongue

Study of copper complexes adsorbed on a silica gel surface chemically modified with 2-amino-1,3,4-thiadiazole

The isotherms of adsorption of CuX2 (X=Cl-, Br-, ClO4-) by silica gel chemically modified with 2-amino-1,3,4-thiadiazole were studied in acetone and ethanol solutions: at 298 K. The following equilibria constants (in 1 mol(-1)) were determined: (a) CuCl2: 3.5 x 10(3) (ac), 2.0 x 10(3) (eth); (b) CuBr2: 2.8 x 10(3) (ac), 2.0 x 10(3) (eth); (c) Cu(ClO4)(2): 1.8 x 10(3) (ac), 1.0 x 10(3) (eth); ac = acetone, eth = ethanol. The electron spin resonance spectra of the surface complexes indicated a tetragonal distorted structure in the case of lower degrees of metal loading on the chemically modified surface. The d-d electronic transition spectra showed that for the ClO4-, complex, the peak of absorption did not change for any degree of metal loading, and for Cl- and Br- complexes, the peak maxima shifted to a higher energy region with a lower metal loading. (C) 1998 Elsevier B.V. B.V. All rights reserved.

Spatial variability of forage yield and soil physical attributes of a Brachiaria decumbens pasture in the Brazilian Cerrado

The objective of this study was to analyze variability, linear and spatial correlations of forage dry mass yield (FDM) and dry matter percentage (DM%) of Brachiaria decumbens with the bulk density (BD), gravimetric (GM) and volumetric (VM) moisture, mechanical resistance to penetration (RP) and organic matter content (OM), at depths 1 (0-0.10 m) and 2 (0.10-0.20 m), in a Red Latosol (Oxisol), in order to select an indicator of soil physical quality and identify possible causes of pasture degradation. The geostatistical grid was installed to collect soil and plant data, with 121 sampling points, over an area of 2.56 ha. The linear correlation between FDM × DM% and FDM × BD2 was low, but highly significant. Spatial correlations varied inversely and positively, respectively. Except for DM% and BD, at both depths, the other attributes showed average to high variability, indicating a heterogeneous environment. Thus, geostatistics emerges as an important tool in understanding the interactions in pasture ecosystems, in order to minimize possible causes of degradation and indicate better alternatives for soil-plant-animal management. The decrease in FDM and increased BD1 are indicators of physical degradation (compaction) of Red Latosol (Oxisol), particularly in the places with the highest concentration of animals and excessive trampling, in Cerrado conditions, in the municipality of Selvíria, Mato Grosso do Sul State, Brazil.

Tobacco smoke-induced left ventricular remodelling is not associated with metalloproteinase-2 or -9 activation

Aim: To investigate the role of MMP-2 and MMP-9 in cardiac remodelling induced by tobacco smoke exposure in rats.Methods: Rats were allocated into two groups: C (n = 9): control animals; ETS (n = 9): exposed to tobacco smoke. After 4months, the animals underwent echocardiography, morphometric study and determination of MMP-2 and MMP-9 activity.Results: ETS rats had larger diastolic (C= 15.6 +/- 1.2 mm/kg, ETS = 18.0 +/- 0.9 mm/kg; p < 0.001) and systolic (C= 7.3 +/- 1.2 mm/kg, ETS = 9.2 0.9 mm/kg; p = 0.001) ventricular diameters adjusted for body weight. Fractional shortening (C= 53 +/- 4.8%, ETS = 48 +/- 3.3%; p = 0.031) and ejection fraction (C= 0. 89 +/- 0.03 5 ETS = 0. 86 +/- 0.02; p = 0.03 0) were smaller in the ETS group. Myocyte cross-sectional area (C= 245 8 mu m(2), ETS=253 8 mu m(2); p = 0.028) was higher in ETS rats. There were no differences in MNtP-2 (C=50 +/- 14%; ETS 43 +/- 11%, p 0.22 +/- 8) or MMP-9 (C=0.36 +/- 0.3%; ETS=0.62 +/- 0.3%, p=0.630) activity between the groups.Conclusion: MMP-2 and MMP-9 did not participate in the remodelling process induced by tobacco smoke exposure. (c) 2007 European Society of Cardiology. Published by Elsevier B.V. All rights reserved.

Hiperinsuflação manual combinada com compressão torácica expiratória para redução do período de internação em UTI em pacientes críticos sob ventilação mecânica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Short courses of mechanical ventilation with high-O-2 levels in elderly rat lungs

Purpose: To evaluate the effects of mechanical ventilation (MV) of high-oxygen concentration in pulmonary dysfunction in adult and elderly rats. Methods: Twenty-eight adult (A) and elderly (E), male rats were ventilated for 1 hour (G-AV1 and G-EV1) or for 3 hours (G-AV3 and G-EV3). A and E groups received a tidal volume of 7 mL/kg, a positive end-expiratory pressure of 5 cm H2O, respiratory rate of 70 cycles per minute, and an inspiratory fraction of oxygen of 1. We evaluated total protein content and malondialdehyde in bronchoalveolar lavages (BAL) and performed lung histomorphometrical analyses. Results: In G-EV1 animals, total protein in BAL was higher (33.0 +/- 1.9 mu g/mL) compared with G-AV1 (23.0 +/- 2.0 mu g/mL). Upon 180 minutes of MV, malondialdehyde levels increased in elderly (G-EV3) compared with adult (G-AV3) groups. Malondialdehyde and total proteins in BAL after 3 hours of MV were higher in elderly group than in adults. In G-EV3 group we observed alveolar septa dilatation and significative increase in neutrofiles number in relation to adult group at 60 and 180 minutes on MV. Conclusion: A higher fraction of inspired oxygen in short courses of mechanical ventilation ameliorates the parameters studied in elderly lungs.

Alpha(2)-adrenergic activation in the lateral parabrachial nucleus induces NaCi intake under conditions of systemic hyperosmolarity

The inhibition of sodium intake by increased plasma osmolarity may depend on inhibitory mechanisms present in the lateral parabrachial nucleus. Activation of alpha(2)-adrenergic receptors in the lateral parabrachial nucleus is suggested to deactivate inhibitory mechanisms present in this area increasing fluid depletion-induced 0.3 M NaCl intake. Considering the possibility that lateral parabrachial nucleus inhibitory mechanisms are activated and restrain sodium intake in animals with increased plasma osmolarity, in the present study we investigated the effects on water and 0.3 M NaCl intake produced by the activation of alpha(2)-adrenergic receptors in the lateral parabrachial nucleus in rats with increased plasma osmolarity. Male Holtzman rats with stainless steel cannulas implanted bilaterally into the lateral parabrachial nucleus were used. One hour after intragastric 2 M NaCl load (2 ml), bilateral injections of moxonidine (alpha(2)-adrenergic/imidazoline receptor agonist, 0.5 nmol/0.2 mu l, n=10) into the lateral parabrachial nucleus induced a strong ingestion of 0.3 M NaCl intake (19.1 +/- 5.5 ml/2 h vs. vehicle: 1.8 +/- 0.6 ml/2 h), without changing water intake (15.8 +/- 3.0 ml/2 h vs. vehicle: 9.3 +/- 2.0 ml/2 h). However, moxonidine into the lateral parabrachial nucleus in satiated rats not treated with 2 M NaCl produced no change on 0.3 M NaCl intake. The pre-treatment with RX 821002 (alpha(2)-adrenergic receptor antagonist, 20 nmol/0.2 mu l) into the lateral parabrachial nucleus almost abolished the effects of moxonidine on 0.3 M NaCl intake (4.7 +/- 3.4 ml/2 h). The present results suggest that alpha(2)-adrenergic receptor activation in the lateral parabrachial nucleus blocks inhibitory mechanisms, thereby allowing ingestion of hypertonic NaCl under conditions of extracellular hyperosmolarity. We suggest that during cell dehydration, circuits subserving sodium appetite are activated, but at the same time strongly inhibited through the lateral parabrachial nucleus. (c) 2006 IBRO. Published by Elsevier Ltd. All rights reserved.

Senna occidentalis Link. (Caesalpiniaceae) imbibition curves for NaCl osmotic potential levels up to 0.6 MPa

An investigation is reported on the statistical model of imbibition curves of the seeds of Senna occidentalis Link. (Caesalpiniaceae), up to Phase II (start of root emission) in osmotic potential levels (0; -0.2; -0.4 and -0.6 MPa), induced NaCl or PEG 6000. The statistical model for both solutions was y = a [1 b exp(-cx)] where y is the fresh matter of seed in g, and x the time of evaluation in h. The analysis of variance of the estimated parameters, showed that with the NaCl solution, the -0.4 and -0.6 MPa levels differed significantly from the 0 and -0.2 MPa levels, and that with the PEG solution, the -0.6 MPa differed from the rest. Prolongation of Phase II occurred as the potential decreased, with both solutions. More reduction in water uptake and prolongation of this phase occurred with the PEG treatment.

Determination of Cd(II), Cu(II) and Ni(II) in aqueous samples by ICP-OES after on-line preconcentration in column packed with silica modified with 2-aminothiazole

This work describes the synthesis and characterization of 2-aminothiazole modified silica gel (SiAT) and the studies of adsorption and pre-concentration (in batch and using a flow-injection system coupled with optical emission spectrometer) of Cd(II), Cu(II) and Ni(II) in aqueous medium. The adsorption capacity for each metal ions in mmolg(-1) was: Cu(II) = 1.18, Ni(II) = 1.15 and Cd(II) = 1.10. The results obtained in the flow experiments showed about 100% of recovering of the metal ions adsorbed in a mini-column packed with 100 mg of SiAT, using 100 mu L of 2.0 mol L-1 HCl solution as eluent. The quantitative sorption-desorption of the metal ions made possible the application of a flow-injection system in the pre-concentration and quantification by ICP-OES of metal ions at trace level in natural water samples.

A solid paraffin-based carbon paste electrode modified with 2-aminothiazole organofunctionalized silica for differential pulse adsorptive stripping analysis of nickel in ethanol fuel

A solid paraffin-based carbon paste electrode modified with 2-aminothiazole organofunctionalized silica (SiAt-SPCPE) was applied to Ni2+ determination in commercial ethanol fuel samples. The proposed method comprised four steps: (1) Ni2+ preconcentration at open circuit potential directly in the ethanol fuel sample, (2) transference of the electrode to an electrochemical cell containing DMG, (3) differential pulse voltammogram registering and (4) surface regeneration by polishing the electrode. The proposed method combines the high Ni2+ adsorption capacity presented by 2-aminothiazole organofunctionalized silica with the electrochemical properties of the Ni(DMG)2 complex, whose electrochemical reduction provides the analytical signal.All experimental parameters involved in the proposed method were optimized. Using a preconcentration time of 20 min, it was obtained a linear range from 7.5 x 10(-9) to 1.0 x 10(-6) mol L-1 with detection limit of 2.0 x 10(-9) mol L-1. Recovery values between 96.5 and 102.4% were obtained for commercial samples spiked with 1.0 mu mol L-1 Ni2+ and the developed electrode was totally stable in ethanolic solutions. The contents of Ni2+ found in the commercial samples using the proposed method were compared to those obtained by graphite furnace atomic absorption spectroscopy by using the F- and t-test. Neither the F- nor t-values exceeded the critical values at 95% confidence level, confirming that there are not statistical differences between the results obtained by both methods. These results indicate that the developed electrode can be successfully employed to reliable Ni2+ determination in commercial ethanol fuel samples without any sample pretreatment or dilution step. (c) 2006 Elsevier B.V. All rights reserved.

Determination of Cu, Ni, and Zn in fuel ethanol by FAAS after enrichment in column packed with 2-aminothiazole-modified silica gel

This work describes the synthesis and characterization of 2-aminothiazole-modified silica gel (SiAT), as well as its application for preconcentration (in batch and column technique) of Cu(II), Ni(II) and Zn(II) in ethanol medium. The adsorption capacities of SiAT determined for each metal ion were (mmol g(-1)): Cu(II)=1.20, Ni(II)=1.10 and Zn(II)=0.90. In addition, results obtained in flow experiments, showed a recovery of ca. 100% of the metal ions adsorbed in a column packed with 500 mg of SiAT. The eluent was 2.0 mol L-1 HCl. The sorption-desorption of the studied metal ions made possible the development of a preconcentration method for metal ions at trace level in fuel ethanol using flame AAS for their quantification.

Search for flavor changing neutral currents via quark-gluon couplings in single top quark production using 2.3 fb(-1) of p(p)over-bar collisions

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Study of Z Boson Production in PbPb Collisions at root s(NN)=2.76 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)