Digital radiography for determination of primary tooth length: in vivo and ex vivo studies

Background. Methods for determining the root canal length of the primary tooth should yield accurate and reproducible results. In vitro studies show some limitations, which do not allow their findings to be directly transferred to a clinical situation. Aim. To compare the accuracy of radiographic tooth length obtained from in vivo digital radiograph with that obtained from ex vivo digital radiograph. Method. Direct digital radiographs of 20 upper primary incisors were performed in teeth (2/3 radicular resorption) that were radiographed by an intraoral sensor, according to the long-cone technique. Teeth were extracted, measured, and mounted in a resin block, and then radiographic template was used to standardise the sensor-target distance (30 cm). The apparent tooth length (APTL) was obtained from the computer screen by means of an electronic ruler accompanying the digital radiography software (CDR 2.0), whereas the actual tooth length (ACTL) was obtained by means of a digital calliper following extraction. Data were compared to the ACTL by variance analysis and Pearson’s correlation test. Results. The values for APTL obtained from in vivo radiography were slightly underestimated, whereas those values obtained from ex vivo were slightly overestimated. No significance was observed between APTL and ACTL. Conclusion. The length of primary teeth estimated by in vivo and ex vivo comparisons using digital radiography was found to be similar to the actual tooth length.

Determination of estrogenic mycotoxins in environmental water samples by low-toxicity dispersive liquid-liquid microextraction and liquid chromatography-tandem mass spectrometry

A novel, simple, rapid and eco-friendly method based on dispersive liquid-liquid microextraction using a bromosolvent was developed to determine six estrogenic mycotoxins (zearalenone, zearalanone, alpha-zearalanol, beta-zearalanol, alpha-zearalenol and beta-zearalenol) in water samples by liquid chromatography-electrospray ionization tandem mass spectrometry in the negative mode (LC-ESI-MS/MS). The optimal conditions for this method include the use of 100 mu L bromocyclohexane as an extraction solvent (using a non-dispersion solvent), 10 mL of aqueous sample (adjusted to pH 4), a vortex extraction time of 2 min, centrifugation for 10 min at 3500 rpm and no ionic strength adjustment. The calibration function was linear and was verified by applying the Mandel fitting test with a 95% confidence level. No matrix effect was observed. According to the relative standard deviations (RSDs), the precision was better than 13% for the repeatability and intermediate precision. The average recoveries of the spiked compounds ranged from 81 to 118%. The method limits of detection (LOD) and quantification (LOQ) considering a 125-fold pre-concentration step were 4-20 and 8-40 ng L-1, respectively. Next, the method was applied to the analysis of the environmental aqueous samples, demonstrating the presence of beta-zearalanol and zearalanone in the river water samples. (C) 2015 Elsevier B.V. All rights reserved.

Development of a simple method for determination of NO2 in air using digital scanner images

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

LC-MS/MS quantitative determination of tetrapterys mucronata alkaloids, a plant occasionally used in ayahuasca preparation

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

Measurement of the inclusive 3-jet production differential cross section in proton-proton collisions at 7 TeV and determination of the strong coupling constant in the TeV range

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

beta-Lactamase-based biosensor for the electrochemical determination of benzylpenicillin in milk

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

Ethanol intake-induced apoptosis in glial cells and axonal disorders in the cerebellar white matter of UChA rats (voluntary ethanol consumers)

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

iCONVERT: an integrated device for the UV-assisted determination of H2S via mid-infrared gas sensors

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

Ditregra - An auxiliary program for structural determination of diterpenes

This work describes the creation of heuristics rules based on 13C-NMR spectroscopy that characterize several skeletal types of diterpenes. Using a collection of 2745 spectra we built a database linked to the expert system SISTEMAT. Several programs were applied to the database in order to discover characteristic signals that identify with a good performance, a large diversity of skeletal types. The heuristic approach used was able to differentiate groups of skeletons based firstly on the number of primary, secondary, tertiary and quaternary carbons, and secondly the program searches, for each group, if there are ranges of chemical shifts that identifies specific skeletal type. The program was checked with 100 new structures recently published and was able to identify the correct skeleton in 65 of the studied cases. When the skeleton has several hundreds of compounds, for example, the labdanes, the program employs the concept of subskeletal, and does not classify in the same group labdanes with double bounds at different positions. The chemical shift ranges for each subskeletal types and the structures of all skeletal types are given. The consultation program can be obtained from the authors. © 1997 - IOS Press. All rights reserved.

Development and validation of an economic, environmental friendly and stability-indicating analytical method for determination of ampicillin sodium for injection by RP-HPLC

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

Validation of a stability indicating capillary electrophoresis method for the determination of darunavir in tablets and comparison with the of infrared absorption spectroscopic method

Darunavir (DRV) is a protease inhibitor used in the treatment of HIV infection, which constitutes a keystone in the therapy of patients infected with this virus. There is no monograph described in official compendia. The literature provides few methods of analysis for the determination of DRV in pharmaceuticals which include TLC, IR, UPLC, HPLC, HPLC-MS, HPLC-MS/MS, but there are no reports of the use of capillary electrophoresis (CE) for the determination of this drug. Thus, this research proposed the development and validation of a CE method for the determination of DRV in tablets. The method was completely validated according to the International Conference on Harmonization guidelines, showing linearity, selectivity, precision, accuracy and robustness. The migration was achieved in less than 1 minute using fused-silica uncoated capillary with an id of 50 μm and total length of 21 cm and voltage of +20 kV. The sample injection was performed in the hydrodynamic mode. The method was linear over the concentration range of 50-200 μg mL-1 with correlation coefficient 0.9998 and limits of detection and quantification of 7.29 and 22.09 μg mL-1, respectively. The drug was subjected to acid, base, oxidation and photolysis degradation. Degradation products were found interfering with the assay of DRV, therefore the method can be regarded as stability indicating. The validated method is useful and appropriate for the routine quality control of DRV in tablets.

Validation of a stability-indicating HPLC method with diode array detection for the determination of beclomethasone dipropionate in aqueous suspension for nebulizer

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Development and validation of infrared spectroscopy method for the determination of darunavir in tabets

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Validation of a HPLC method for determination of glutamine in food additives using post-column derivatization

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Exploratory study of electromyographic behavior of the vastus medialis and vastus lateralis at neuromuscular fatigue onset

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)