Avaliação in vivo do potencial estrogênico de amostra de água para consumo humano produzida por estação de tratamento do estado de São Paulo

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

Efeitos da congelação lenta e da vitrificação na viabilidade, ultraestrutura e expressão gênica de embriões caninos produzidos in vivo

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

Efeito protetor in vivo de vacinas de células dendríticas sensibilizadas com RNA de células MC-38 pré-tratadas com agentes antineoplásticos em concentrações efetivas minímas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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.

Effects of pH and fluoride concentration of dentifrices on fluoride levels in saliva, biofilm, and biofilm fluid in vivo

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

Imprinted gene expression in in vivo- And in vi/ro-produced bovine embryos and chorio-allantoic membranes

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

Evaluation of the anti-mycobacterium tuberculosis activity and in vivo acute toxicity of annona sylvatic

Background The recent emergence of extensively multidrug-resistant Mycobacterium tuberculosis strains has further complicated the control of tuberculosis. There is an urgent need for the development of new molecular candidates antitubercular drugs. Medicinal plants have been an excellent source of leads for the development of drugs. The aim of this study was to evaluate the in vitro activity of 28 alcoholic extracts and essential oils of native and exotic Brazilian plants against Mycobacterium tuberculosis and to further study these extracts through chemical fractionation, the isolation of their constituents, and an evaluation of the in vivo acute toxicity of the active extracts. To the best of our knowledge this is the first chemical characterization, antituberculosis activity and acute toxicity evaluation of Annona sylvatica. Methods The anti-mycobacterial activity of these extracts and their constituent compounds was evaluated using the resazurin reduction microtiter assay (REMA). To investigate the acute toxicity of these extracts in vivo, female Swiss mice were treated with the extracts at doses of 500, 1000 and 2000 mg · kg-1 of body weight. The extracts were characterized by LC-MS, and the constituents were isolated and identified by chromatographic analysis of spectroscopic data. Results Of the 28 extracts, the methanol extract obtained from the leaves of Annona sylvatica showed anti-mycobacterial activity with an minimal inhibitory concentration (MIC) of 184.33 μg/mL, and the ethyl acetate fraction (EAF) resulting from liquid-liquid partitioning of the A. sylvatica extract showed an MIC of 115.2 μg/mL. The characterization of this extract by LC-MS identified flavonoids and acetogenins as its main constituents. The phytochemical study of the A. sylvatica EAF resulted in the isolation of quercetin, luteolin, and almunequin. Conclusions Among the compounds isolated from the EAF, luteolin and almunequin were the most promising, with MICs of 236.8 μg/mL (827.28 μM) and 209.9 μg/mL (328.48 μM), respectively. The acute administration of the EAF fraction in doses of 500, 1000, and 2000 mg · kg-1 of body weight did not cause signs of toxicity in the treated animals.

Post-thaw viability of in vivo-produced canine blastocysts cryopreserved by slow freezing

The objectives were to evaluate the reexpansion blastocoele rate, post-thaw viability, and in vitro development of canine blastocysts cryopreserved by slow freezing in 1.0 m glycerol (GLY) or 1.5 m ethylene glycol (EG). Fifty-one in vivo-produced canine blastocysts were randomly allocated in two groups: GLY (n = 26) and EG (n = 25). After thawing, embryos from MO were immediately stained with the fluorescent probes propidium iodide and Hoechst 33 342 to evaluate cellular viability. Frozen-thawed embryos from M3 and M6 were cultured in SOFaa medium + 10% FCS at 38.5 degrees C under an atmosphere of 5% CO2 with maximum humidity, for 3 and 6 days, respectively, and similarly stained. The blastocoele reexpansion rate (24 h after in vitro culture) did not differ between GLY (76.5%) and EG (68.8%). Post-thaw viable cells rate were not significantly different between GLY and EG (66.5 +/- 4.8 and 57.3 +/- 4.8, respectively, mean +/- SEM), or among MO (62.3 +/- 5.7%), M3 (56.9 +/- 6.0%), and M6 (66.5 +/- 6.0%). In conclusion, canine blastocysts cryopreserved by slow freezing in 1.0 m glycerol or 1.5 m ethylene glycol, had satisfactory blastocoele reexpansion rates, similar post-thawing viability, and remained viable for up to 6 days of in vitro culture. (C) 2012 Elsevier Inc. All rights reserved.

In vivo hydroquinone exposure impairs MCP-1 secretion and monocyte recruitment into the inflamed lung

Alveolar macrophages (AMs) are important cells in the resolution of the inflammatory process and they come into direct contact with inhaled pollutants. Hydroquinone (HQ) is an environmental pollutant and a component of cigarette smoke that causes immunosuppressive effects. In the present work, we showed that mice exposed to low levels of aerosolized HQ (25 ppm; 1 h/day/5 days) presented impaired mononuclear cell migration to the lipopolysaccharide (LPS)-inflamed lung. This may have been due to reduced monocyte chemoattractant protein-1 (MCP-1) secretion into bronchoalveolar lavage fluid (BALF), and it was not related to alterations to mononuclear cell mobilization into the blood or adhesion molecules expression on mononuclear cell membranes. Corroborating the actions of HQ on MCP-1 secretion, reduced MCP-1 concentrations were also found in the supernatant of ex vivo AM and tracheal tissue collected from HQ-exposed mice. A direct action of HQ on MCP-1 secretion, resulting from impaired gene synthesis, was verified by in vitro incubation of naive AMs or tracheal tissue with HQ. The role of reduced levels of MCP-1 in the BALF on monocyte migration was analysed in the human monocytic lineage THP-1 in in vitro chemotaxis assays, which showed that the reduced concentrations of MCP-1 found in the BALF or cell supernatants from HQ-exposed mice impaired cell migration. Considering the fact that MCP-1 presents a broad spectrum of actions on pathophysiological conditions and that resident mononuclear cells are involved in lung tissue homeostasis and in immune host defence, the mechanism of HQ toxicity presented herein might be relevant to the genesis of infectious lung diseases in smokers and in inhabitants of polluted areas. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

In vivo accuracy of conventional and digital radiographic methods in confirming root canal working length determination by Root ZX

Objectives: To compare, in vivo, the accuracy of conventional and digital radiographic methods in determining root canal working length. Material and Methods: Twenty-five maxillary incisor or canine teeth from 22 patients were used in this study. Considering the preoperative radiographs as the baseline, a 25 K file was inserted into the root canal to the point where the Root ZX electronic apex locator indicated the APEX measurement in the screen. From this measurement, 1 mm was subtracted for positioning the file. The radiographic measurements were made using a digital sensor (Digora 1.51) or conventional type-E films, size 2, following the paralleling technique, to determine the distance of the file tip and the radiographic apex. Results: The Student "t" test indicated mean distances of 1.11 mm to conventional and 1.20 mm for the digital method and indicated a significant statistical difference (p<0.05). Conclusions: The conventional radiographic method was found to be superior to the digital one in determining the working length of the root canal.

Influence of pulp condition on the accuracy of an electronic foramen locator in posterior teeth: an in vivo study

The aim of this study was to assess, in vivo, the accuracy of the NovApex (R) electronic foramen locator in determining working length (WL) in vital and necrotic posterior teeth. The NovApex (R) was used in 144 canals: 35 teeth with vital pulps (68 canals) and 42 teeth with necrotic pulps (76 canals). WL was measured with the NovApex (R) locator and confirmed using the radiographic method. Differences between electronic and radiographic measurements ranging between 0.0 and 0.4 millimeters were classified as acceptable; differences equal to or greater than 0.5 millimeter were considered unacceptable. Pearson's chi-square test was used to assess the influence of pulp condition on the accuracy of NovApex (R) (alpha = 0.05). Regardless of pulp condition, differences between electronic and radiographic WL measurements were acceptable in 73.61% of the canals. No statistically significant differences in accuracy were observed when comparing vital and necrotic canals (p > 0.05). There were 38 unacceptable measurements. In none of these cases was the file tip located beyond the radiographic apex; in 32, it was located short of the NovApex (R) measurement. Pulp condition had no significant effect on the accuracy of NovApex (R).

In vivo study of laser irradiation of fractionated drug administration based mechanism for effective photodynamic therapy in rat liver

Up-regulation of stress-activated proteins in cancer cells plays a protective role against photodynamic induced apoptosis. Post photodynamic therapy extracted normal rat liver tissue usually shows a fraction of surviving cells, the photodynamic resistant cells, residing in the necrotic region. To treat these photo-dynamic resistant cells a technique has been proposed based on fractionated drug administration of diluted photosensitizer, keeping the net concentration (5 mg/kg) constant, and subsequently varying drug light interval (DLI). Flourescence measurements were made for the presence of photosensitizer in a tissue. For qualitative analysis both histological and morphological studies were made. Although preliminary aim of this approach was not achieved but there were some interesting observation made i.e. for higher dilution of photosensitizer there was a sharp boundary between necrotic and normal portion of tissue. An increase in the absorption coefficient (alpha) from 2.7 -> 2.9 was observed as photosensitizer was diluted while the corresponding threshold dose (D (th)) persistently decreases from (0.10 -> 0.02) J/cm(2) when irradiated with a 635 nm laser fluence of 150 J/cm(2).

In silico and in vivo analysis reveal a novel gene in Saccharomyces cerevisiae trehalose metabolism

Abstract Background The ability to respond rapidly to fluctuations in environmental changes is decisive for cell survival. Under these conditions trehalose has an essential protective function and its concentration increases in response to enhanced expression of trehalose synthase genes, TPS1, TPS2, TPS3 and TSL1. Intriguingly, the NTH1 gene, which encodes neutral trehalase, is highly expressed at the same time. We have previously shown that trehalase remains in its inactive non-phosphorylated form by the action of an endogenous inhibitor. Recently, a comprehensive two-hybrid analysis revealed a 41-kDa protein encoded by the YLR270w ORF, which interacts with NTH1p. Results In this work we investigate the correlation of this Trehalase Associated Protein, in trehalase activity regulation. The neutral trehalase activity in the ylr270w mutant strain was about 4-fold higher than in the control strain. After in vitro activation by PKA the ylr270w mutant total trehalase activity increased 3-fold when compared to a control strain. The expression of the NTH1 gene promoter fused to the heterologous reporter lacZ gene was evaluated. The mutant strain lacking YLR270w exhibited a 2-fold increase in the NTH1-lacZ basal expression when compared to the wild type strain. Conclusions These results strongly indicate a central role for Ylr270p in inhibiting trehalase activity, as well as in the regulation of its expression preventing a wasteful futile cycle of synthesis-degradation of trehalose.

Monitoramento in vivo por imagem por ressonância magnética de células C6 de glioma marcadas com nanopartículas superparamagnéticas de óxido de ferro

OBJECTIVE: The aim of the current study was to monitor the migration of superparamagnetic iron oxide nanoparticle (SPION)-labeled C6 cells, which were used to induce glioblastoma tumor growth in an animal model, over time using magnetic resonance imaging (MRI), with the goal of aiding in tumor prognosis and therapy. METHODS: Two groups of male Wistar rats were used for the tumor induction model. In the first group (n=3), the tumors were induced via the injection of SPION-labeled C6 cells. In the second group (n=3), the tumors were induced via the injection of unlabeled C6 cells. Prussian Blue staining was performed to analyze the SPION distribution within the C6 cells in vitro. Tumor-inducing C6 cells were injected into the right frontal cortex, and subsequent tumor monitoring and SPION detection were performed using T2- and T2*-weighted MRI at a 2T field strength. In addition, cancerous tissue was histologically analyzed after performing the MRI studies. RESULTS: The in vitro qualitative evaluation demonstrated adequate distribution and satisfactory cell labeling of the SPIONs. At 14 or 21 days after C6 injection, a SPION-induced T2- and T2*-weighted MRI signal reduction was observed within the lesion located in the left frontal lobe on parasagittal topography. Moreover, histological staining of the tumor tissue with Prussian Blue revealed a broad distribution of SPIONs within the C6 cells. CONCLUSION: MRI analyses exhibit potential for monitoring the tumor growth of C6 cells efficiently labeled with SPIONs.

Comparison of indigestible markers from in situ and in vivo incubation to predict apparent digestibility in hay- and corn-fed horses

Four castrated crossbred horses were used in a randomized block design to study the use of indigestible internal markers iNDF and iADF obtained in situ (from bovines) or in vivo (from equines). Treatments consisted of determining digestibility by the direct method comprising total feces collection (TC) and by the indirect method comprising internal markers iNDF and iADF obtained by in situ incubation in bovine rumen or in vivo by the mobile nylon bag (MNB) technique with horses. iNDF-IV and iADF-IV resulted in better marker recovery rate (RR) (91.50%), similar to TC. The in situ technique resulted in lower RR values for the two indigestible markers, averaging 86.50% (p < 0.05). Estimates of the nutrient coefficient of digestibility (CD) were adequately predicted by iADF-IV, for horses fed on hay exclusively, with rates 46.41, 48.16, 47.92 and 45.51% for dry matter (DM), organic matter (OM), FDN and gross energy, respectively. Results show that MNB may be used to obtain iADF in horses fed on coast-cross hay exclusively, whereas NDFi and ADFi were selected for horses fed on mixed diets to predict the coefficient of nutrient digestibility.