Pulmonary neutrophil recruitment and bronchial reactivity in formaldehyde-exposed rats are modulated by mast cells and differentially by neuropeptides and nitric oxide

We have used a pharmacological approach to study the mechanisms underlying the rat lung injury and the airway reactivity changes induced by inhalation of formaldehyde (FA) (1% formalin solution, 90 min once a day, 4 days). The reactivity of isolated tracheae and intrapulmonary bronchi were assessed in dose-response curves to methacholine (MCh). Local and systemic inflammatory phenomena were evaluated in terms of leukocyte countings in bronchoalveolar lavage (BAL) fluid, blood, bone marrow lavage and spleen. Whereas the tracheal reactivity to MCh did not change, a significant bronchial hyporesponsiveness (BHR) was found after FA inhalation as compared with naive rats. Also, FA exposure significantly increased the total cell numbers in BAL, in peripheral blood and in the spleen, but did not modify the counts in bone marrow. Capsaicin hindered the increase of leukocyte number recovered in BAL fluid after FA exposure. Both compound 48/80 and indomethacin were able to prevent the lung neutrophil influx after FA, but indomethacin had no effect on that of mononuclear cells. Following FA inhalation, the treatment with sodium cromoglycate (SCG), but not with the nitric oxide (NO) synthase inhibitor L-NAME, significantly reduced the total cell number in BAL. Compound 48/80, L-NAME and SCG significantly prevented BHR to MCh after FA inhalation, whereas capsaicin was inactive in this regard. on the other hand, indomethacin exacerbated BHR. These data suggest that after FA inhalation, the resulting lung leukocyte influx and BHR may involve nitric oxide, airway sensory fibers and mast cell-derived mediators. The effect of NO seemed to be largely restricted to the bronchial tonus, whereas neuropeptides appeared to be linked to the inflammatory response, therefore indicating that the mechanisms responsible for the changes of airway responsiveness caused by FA may be separate from those underlying its inflammatory lung effects. (c) 2005 Elsevier B.V. All rights reserved.

Clavulanic acid production by immobilized cells if Streptomyces clavuligerus

A clavulanic acid production process with immobilized Streptomyces clavuligerus cells was investigated. Cells were immobilized in diatomaceous earth, calcium alginate gel as well as in the form of natural pellets and cultivated in shake flasks in a medium containing glycerol and soytone as the carbon and nitrogen sources, respectively. In all experiments growth occurred in the first 48 h and glycerol consumption after 72 h, while clavulanic acid production was observed between 48 and 60h, with gradual degradation after this period. The natural pellets presented higher product concentration as compared with the cells immobilized in supports. However, calcium alginate was found to be the best support in relation to cell retention capacity.

Radiographic and histomorphometric analysis of bone healing using autogenous graft associated with platelet-rich plasma obtained by 2 different methods

The aim of this study was to conduct radiographic and histomorphometric analysis of bone healing in the calvaria of rabbits, using an autogenous graft associated with PRP obtained by 2 different methods. Thirty rabbits were divided into control and experimental groups. Lesions were produced in the calvaria and filled with autogenous graft ( control) or autogenous graft and PRP obtained by the Anitua or modified Sonnleitner methods. The animals were humanely killed 15 days after surgery and the calvarias were radiographed. The radiographs were digitized to assess the radiographic density. By histologic images of the lesion, the bone matrix was quantified. There were no significant differences in the radiographic density and the bone matrix area between the groups. The association of PRP with autogenous bone did not improve the healing process, irrespective of the method used early during healing.

Sorption and preconcentration of some heavy metals by 2-mercaptobenzothiazole-clay

2-Mercaptobenzothiazole loaded on previously treated clay was prepared, characterized and used for sorption and preconcentration of Hg(II), Pb(II), Zn(II), Cd(II), Cu(II) and Mn(II) from an aqueous solution. The support used was a natural clay previously treated with sulphuric acid solution. Adsorption isotherms of metal ions from aqueous solutions as function of pH were studied at 298 K. Conditions for quantitative retention and elution were established for each metal by batch and column methods. The chemically treated clay was very selective to Hg(II) in solution in which Zn(II), Cd(II), Pb(II), Cu(II) and Mn(II) were also present. © 1995.

Enhanced photocatalytic reduction of Hg(II) in aqueous medium by 2-aminothiazole-modified TiO2 particles

This work describes the synthesis and characterization of 2-aminothiazole-modified titania and its application on Hg (II) photoreduction in aqueous medium. Infrared spectroscopy confirmed the chemical modification of the titania matrix. The number of 2-aminothiazole groups attached to the titania was determined by Kjeldahl's method. The photocatalytic experiments were carried out in a cylindrical photoreactor thermostatted at 298 K. The resulting modified photocatalyst 2-aminothiazole titania (TiAT) revealed an enhance in the Hg (II) photoreduction capacity at studied pH values (3, 7 and 9). In addition, sorption studies showed that the photocatalyst TiAT presented a lower equilibrium time and a higher sorption capacity of Hg(II) ion, demonstrating that sorption plays a fundamental role in the photoreduction mechanism. ©2006 Sociedade Brasileira de Química.

Fluoride intake from regular and low fluoride dentifrices by 2-3-year-old children: Influence of the dentifrice flavor

This study evaluated the fluoride intake from dentifrices with different fluoride concentrations ([F]) by children aged 24-36 months, as well as the influence of the dentifrice flavor in the amount of fluoride ingested during toothbrushing. Thirty-three children were randomly divided into 3 groups, according to the [F] in the dentifrices: G-A (523 μgF/g), G-B (1,062 μgF/g) and G-C (1,373 μgF/g). Dentifrices A and B are marketed for children, while dentifrice C is a regular product. The amount of F ingested was indirectly obtained, subtracting the amount expelled and the amount left on the toothbrush from the amount initially loaded onto the brush. The results were analyzed by ANOVA, Tukey's test and linear regression analysis (p < 0.05). Children ingested around 60% of the dentifrice loaded onto the brush, but no significant differences were seen among the groups (p > 0.05). Mean daily fluoride intake from dentifrice for G-A, G-B and G-C was 0.022 a, 0.032 a and 0.061 b mg F/kg body weight, respectively (p < 0.01). There was a strong positive correlation (r = 0.86, p < 0.0001) between the amount of dentifrice used and the amount of fluoride ingested during toothbrushing. The results indicate the need for instructing children's parents and care givers to use a small amount of dentifrice (< 0.3 g) to avoid excessive ingestion of fluoride. The use of low-[F] dentifrices by children younger than 6 years also seems to be a good alternative to minimize fluoride intake. Dentifrice flavor did not influence the percentage of fluoride intake.

Invasion of differentiated intestinal caco-2 cells is a sporadic property among atypical enteropathogenic escherichia coli strains carrying common intimin subtypes

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

Effect of LPS treatment on the viability and chemokine synthesis by epithelial cells and gingival fibroblasts

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

Radiographic and clinical evaluation of zygomatico-maxillary complex fractures treated by 2.0 miniplates system

The zygomaticomaxillary complex (ZMC) is the second highly incidental of facial fractures. According to the anatomical complexity, there are many reports in the literature about this trauma, mainly related to treatment for these fractures. With the purpose of evaluating clinically and radiographically the stability of unilateral zygomatic fractures treated by surgical reduction and fixed in two points by stable internal fixation, this research was proposed. Twenty patients with zygomatic fractures were evaluated and compared with twenty nonfractured patients. The results showed that there were no statistically significant differences among the obtained data, perimeter and area, of the treated and contra-lateral sides of the experimental group. When compared to the control group the differences were not statistically significant. We also performed a comparison of the distance between the nasal bone and zygomatic prominence in all groups the results were also satisfactory.

Antigenicity of Primary Endodontic Infection against Macrophages by the Levels of PGE(2) Production

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

Propolis immunomodulatory activity on TLR-2 and TLR-4 expression by chronically stressed mice

Our group has been investigating the immunomodulatory activity of propolis in stressed mice. In this work, we wish to report the action of propolis in chronically stressed mice, assessing the Toll-like receptor (TLR2 and TLR-4) expression by spleen cells and corticosterone levels as a stress indicator. Male C57BL/6 mice were divided into four groups: G1 was considered the control; G2 was treated with propolis (200mg kg(-1)); G3 was submitted to restraint stress for 14 days; and G4 was treated with propolis and immediately submitted to stress. After sacrifice, spleens were removed and TLR-2 and TLR-4 gene expression was analysed. TLR-2 and TLR-4 expression was increased in propolis-treated mice, and propolis administration to stressed mice prevented the inhibition of TLR-2 and TLR-4 expression. No differences were seen in the corticosterone levels among the groups. Propolis exerted an immunomodulatory action in chronically stressed mice, upregulating TLR-2 and TLR-4 mRNA expression, contributing to the recognition of microorganisms and favouring the initial steps of the immune response during stress.

Inhibitory effect of PGE(2) on the killing of Paracoccidioides brasiliensis by human monocytes can be reversed by cellular activation with cytokines

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

Cytologic analysis of alterations induced by smoking and by alcohol consumption

Objective: To analyze cytologically the buccal mucosa of smoking and nonsmoking volunteers to determine what cellular changes are induced by cigarettes and alcohol consumption. Study Design: In order to evaluate cellular changes induced by smoking and alcohol consumption, exfoliative cytology was used for the analysis of mucosal smears obtained from the buccal mucosa of 25 smokers and 25 nonsmokers. The number of cigarettes consumed, duration of smoking, presence or absence of alcohol ingestion, ingested alcohol dose and frequency of consumption, and most frequently used type of alcoholic beverage were determined using a questionnaire. Three smears from each individual stained by the Papanicolaou method were analyzed quantitatively and qualitatively under a light microscope by 2 experienced examiners in terms of inflammatory and dysplastic alterations and of the degree of epithelial maturation. Results: Although numerous alterations were observed in smokers they corresponded up to only Papanicolaou class II and were not significantly different from nonsmokers (Mann-Whitney and χ 2 tests, p < 0.05). A higher proportion of inflammatory cells (polymorphonuclear and mononuclear cells) were obtained from smokers as compared to nonsmokers, while the proportion of bacteria was similar in the 2 groups. Conclusion: The findings indicate that even after a short period of cigarette use and alcohol consumption, inflammatory alterations were detectable on exfoliative cytology of the buccal mucosa in a young group, demonstrating the usefulness of cytology for early detection in smokers. © The International Academy of Cytology.

Zoledronic acid decreases gene expression of vascular endothelial growth factor and basic fibroblast growth factor by human epithelial cells

Delayed wound healing in patients taking bisphosphonates could result from decreased expression of growth factors, which are directly related to cell proliferation and migration. In this study, we evaluated the gene expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) by epithelial cells exposed to zoledronic acid 5 μmol for 48 h using real-time polymerase chain reaction. The gene expression of VEGF and bFGF by epithelial cells exposed to zoledronic acid decreased by 34% and 51%, respectively (p = 0.0001 and p = 0.0001). We conclude that zoledronic acid can decrease the expression of growth factors by epithelial cells. © 2013 The British Association of Oral and Maxillofacial Surgeons.

MRE11A and SKP2 genes are associated with the increased cytotoxicity induced by the synergistic effects of cisplatin and gemcitabine in bladder cancer cells

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