Cristiane Cademartori Danesi

Pre-treatment with ebselen and vitamin E modulate acetylcholinesterase activity: interaction with demyelinating agents

The ethidium bromide (EB) demyelinating model was associated with vitamin E (Vit E) and ebselen (Ebs) treatment to evaluate acetylcholinesterase (AChE) activity in the striatum (ST), hippocampus (HP), cerebral cortex (CC) and erythrocytes. Rats were divided into seven groups: I—Control (saline), II—(canola); III—(Ebs), IV—(Vit E); V—(EB); VI—(EB + Ebs) and VII—(EB + Vit E). At 3 days after the EB injection, AChE activity in the CC and HC was significantly reduced in groups III, IV, V, VI and VII (p < 0.05) and in the ST it was reduced in groups III and V (p < 0.05) when compared to the control group. At 21 days after the EB injection, AChE activity in the CC was significantly reduced in groups III, IV and V, while in groups VI and VII a significant increase was observed when compared to the control group. In the HC and ST, AChE activity was significantly reduced in groups V, VI and VII when compared to the control group (p < 0.05). In the erythrocytes, at 3 days after the EB injection, AChE activity was significantly reduced in groups III, IV, V, VI and VII and at 21 days there was a significant reduction only in groups VI and VII (p < 0.05) when compared to the control group. In conclusion, this study demonstrated that Ebs and Vit E interfere with the cholinergic neurotransmission by altering AChE activity in the different brain regions and in the erythrocytes. Furthermore, treatment with Vit E and Ebs protected against the demyelination lesion caused by EB. In this context, we can suggest that ebselen and Vit E should be considered potential therapeutics and scientific tools to be investigated in brain disorders associated with demyelinating events.

Prevalência e fatores associados às manifestações bucais em pacientes HIV positivos atendidos em cidade sul-brasileira

The aim of the study was to assess the prevalence of oral lesions in AIDS patients and identify associated factors. A cross-sectional study collected data from interviews, clinical examination, and a review of medical records for adult patients treated at the HIV/AIDS clinic in the University Hospital of the Federal University in Rio Grande, Rio Grande do Sul State, Brazil, focusing on socio-demographic, immune status, and treatment factors. Poisson regression was used in a hierarchical analytical model. From April 2006 to January 2007, 300 patients were observed (51% males; mean age 40 years). Of the total, 39% presented oral lesions, with candidiasis as the most frequent (59.1%), followed by hairy leukoplakia (19.5%). Women showed a lower risk of oral lesions, and there was an inverse association with CD4 count. Increased risk was associated with lower schooling, low income, smoking, alcohol addiction, time since HIV seroconversion, and higher viral load. The data confirm the increased prevalence of opportunistic oral lesions and show their relationship to socioeconomic conditions and modifiable habits and customs.O objetivo deste estudo foi avaliar a prevalencia de lesoes bucais entre pacientes HIV positivos e identificar fatores associados a tais lesoes. Foi realizado estudo transversal que coletou dados mediante entrevista, exame clinico e consulta aos prontuarios medicos de pacientes adultos atendidos no Servico de HIV-AIDS do Hospital Universitario da Universidade Federal do Rio Grande, Rio Grande do Sul, Brasil, sendo considerados fatores socio-demograficos, imunologicos e terapeuticos. Foi utilizada a regressao de Poisson num modelo hierarquico de analise. Entre abril de 2006 a janeiro de 2007 foram observados 300 pacientes, sendo 51% do sexo masculino e media de idade de 40 anos; 39% apresentaram lesoes bucais, sendo a candidiase a mais frequente (59,1%), seguida de leucoplasia pilosa (19,5%). As mulheres apresentaram um risco menor, com observância de uma associacao inversa com o CD4. Houve um risco maior entre aqueles pacientes com menor escolaridade, menor renda, tabagistas, dependentes do alcool, com maior tempo de infeccao pelo HIV e carga viral mais elevada. Os dados confirmaram a elevada prevalencia das manifestacoes bucais oportunistas e evidenciaram a sua relacao com a situacao social, assim como sua relacao com determinados habitos e costumes passiveis de modificacao.

Evaluation of the genotoxicity of cisplatin, paclitaxel and 5-fluorouracil combined treatment in the Drosophila wing-spot test

The somatic mutation and recombination test in Drosophila melanogaster was applied to analyze the mutagenic and recombinagenic activity of the chemotherapeutic drugs cisplatin, paclitaxel, and 5-fluorouracil, comparing the effects observed in combinatory treatments with those observed in single administrations. The results obtained in two different genotypes allowed to quantitatively and qualitatively estimate the contribution of genotoxic effects. The results obtained with the individual drug treatments showed that cisplatin and 5-fluorouracil were genotoxic, being able to increase the frequency of total spots on both genotypes. While cisplatin preferentially induced DNA damage of recombinational origin, all the damages induced by 5-fluorouracil were caused by gene and/or chromosome mutations, and the aneuploidogenic compound paclitaxel was not genotoxic. The combination of these drugs does not exert a synergist genotoxic effect in both genotypes compared to the single-agent administration. Instead, it was observed a modification in the proportion of mutation and recombination to the final genotoxicity observed. The antiproliferative activity of PAC could be responsible for the non-synergic genotoxic effect observed. Based on our results it is possible to suggest that cisplatin/paclitaxel/5-fluorouracil treatment regimen cannot impose a higher risk of the development of genotoxicity-associated secondary tumors in comparison to their individual applications.

Neuroprotective effects of quercetin on memory and anxiogenic-like behavior in diabetic rats: Role of ectonucleotidases and acetylcholinesterase activities

The present study investigated the protective effect of quercetin (Querc) on memory, anxiety-like behavior and impairment of ectonucleotidases and acetylcholinesterase (AChE) activities in brain of streptozotocin-induced diabetic rats (STZ-diabetes). The type 1 diabetes mellitus was induced by an intraperitoneal injection of 70mg/kg of streptozotocin (STZ), diluted in 0.1M sodium-citrate buffer (pH 4.5). Querc was dissolved in 25% ethanol and administered by gavage at the doses of 5, 25 and 50mg/kg once a day during 40days. The animals were distributed in eight groups of ten animals as follows: vehicle, Querc 5mg/kg, Querc 25mg/kg, Querc 50mg/kg, diabetes, diabetes plus Querc 5mg/kg, diabetes plus Querc 25mg/kg and diabetes plus Querc 50mg/kg. Querc was able to prevent the impairment of memory and the anxiogenic-like behavior induced by STZ-diabetes. In addition, Querc prevents the decrease in the NTPDase and increase in the adenosine deaminase (ADA) activities in SN from cerebral cortex of STZ-diabetes. STZ-diabetes increased the AChE activity in SN from cerebral cortex and hippocampus. Querc 50mg/kg was more effective to prevent the increase in AChE activity in the brain of STZ-diabetes. Querc also prevented an increase in the malondialdehyde levels in all the brain structures. In conclusion, the present findings showed that Querc could prevent the impairment of the enzymes that regulate the purinergic and cholinergic extracellular signaling and improve the memory and anxiety-like behavior induced by STZ-diabetes.

Mutagenic evaluation of combined paclitaxel and cisplatin treatment in somatic cells of Drosophila melanogaster

Recent studies have added paclitaxel (PAC) to traditional cisplatin (CIS) regimen to treat squamous cell carcinoma of the head and neck. The target of these antineoplastic agents is nuclear DNA for CIS and microtubules for PAC, although it is not restricted to malignant cells. In this study, the genotoxicity of the combined treatment of PAC and CIS was investigated using the standard version of the wing Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster. Quantitative and qualitative genotoxic effects of these compounds were estimated by comparing wing spot frequencies in marker-heterozygous to balancer-heterozygous flies. Two different concentrations of PAC (0.0025 and 0.005mM) and CIS (0.025 and 0.05mM) as well as combinations of them were employed. The results demonstrated that the spindle poison PAC alone was not genotoxic in this test system, while CIS was able to induce a high incidence of DNA damage in both genotypes, mainly related to somatic recombination. The data obtained for the combined treatments showed that its genotoxicity varied with the concentrations used. In small concentrations the number of total spots induced by combination was reduced in relation to CIS 0.025mM just for marker-heterozygous flies, showing that somatic recombination was the prevalent event involved. At higher concentrations the combined treatment showed significant reductions in the frequencies of large single spots, for both genotypes, and twin spots for marker-heterozygous flies, but did not significantly reduce the total spots frequency in either genotype. The data suggest that aneugenic activity of PAC could be responsible for the reduction in the genotoxicity of CIS.

Genotoxicity testing of combined treatment with cisplatin, bleomycin, and 5-fluorouracil in somatic cells of Drosophila melanogaster.

The simultaneous treatment with the cross-linking agent cisplatin, the radiomimetic antitumoral drug bleomycin, and the anti-metabolite drug 5-fluorouracil has been used as a regimen to treat patients with squamous cell carcinoma of the head and neck. Considering that these drugs interact directly with DNA, one of the important late-occurring complications from treatment of primary malignancies is the therapy-related secondary cancers as a result of the genotoxic activity of the drugs on normal cells. In this sense, the genotoxicity of this combination was evaluated using the wing somatic mutation and recombination test in Drosophila melanogaster. The mutant spots observed in marker-heterozygous and balancer-heterozygous flies were compared in order to quantitatively and qualitatively estimate the genotoxic effect of these drugs. Cisplatin (0.003 and 0.006mM), bleomycin (0.005 and 0.01mM), and both combinations preferentially induced recombinational events, while mutation is the major event regarding the genetic toxicity of 5-fluorouracil (0.025 and 0.05mM). The combination of these drugs produced synergistic and antagonistic genotoxic effects, depending on the concentrations used, which could impose a higher risk of secondary effects associated with their genotoxic effects, emphasizing the importance of long-term monitoring in patients being treated with these drugs.

CONTRIBUIÇÃO AO ESTUDO DO CISTO RADICULAR REVISÃO DA LITERATURA

Os autores apresentam revisao da literatura sobre o cisto radicular. Sao abordados topicos, taiscomo: etiologia, patogenia, caracteristicas clinicas, caracteristicas radiograficas, caracteristicashistopatologicas e outros aspectos relevantes associados a lesao. O objetivo desta revisao daliteratura foi realizar uma avaliacao da patologia, coletando a opiniao de varios pesquisadores eresultados de pesquisas sobre o assunto.

Role of the adjunctive antimicrobial photodynamic therapy to periodontal treatment at plasmatic oxidative stress and vascular behavior

BACKGROUND To evaluate for the first time in vivo the effects of methylene blue (MB) photosensitizer dissolved in ethanol in antimicrobial photodynamic therapy (aPDT) as adjuvant periodontal treatment, at plasmatic oxidative stress and vascular behavior in rat model. METHODS Wistar rats were divided into negative control (NC, no periodontitis) and positive control (PC, with periodontitis, without any treatment). The other groups had periodontitis and were treated with scaling and root planing (SRP); SRP+aPDT+MB dissolved in water (aPDT I); SRP+aPDT+MB dissolved in ethanol (aPDT II). The periodontitis was induced by ligature at the mandibular right first molar. At 7/15/30days, rats were euthanized, the plasma was used to determine oxidative stress parameters and gingival tissue for histomorphometric analysis. RESULTS PC showed higher thiobarbituric acid reactive substances levels in 7/15/30days. aPDT II was able to block the lipid peroxidation, especially between 15th and 30th days. Glutathione reduced levels were consumed in PC, aPDT I and II groups throughout the experiment. aPDT II increased the vitamin C levels which were restored in this group in the 30th day. aPDT II group showed the highest number of blood vessels. CONCLUSION In summary, the aPDT with MB dissolved in ethanol provides better therapeutic responses in periodontitis treatment.

Dental flossing as a diagnostic method for proximal gingivitis: a validation study

This study evaluated the clinical diagnosis of proximal gingivitis by comparing two methods: dental flossing and the gingival bleeding index (GBI). One hundred subjects (aged at least 18 years, with 15% of positive proximal sites for GBI, without proximal attachment loss) were randomized into five evaluation protocols. Each protocol consisted of two assessments with a 10-minute interval between them: first GBI/second floss, first floss/second GBI, first GBI/second GBI, first tooth floss/second floss, and first gum floss-second floss. The dental floss was slid against the tooth surface (TF) and the gingival tissue (GF). The evaluated proximal sites should present teeth with established point of contact and probing depth ≤ 3mm. One trained and calibrated examiner performed all the assessments. The mean percentages of agreement and disagreement were calculated for the sites with gingival bleeding in both evaluation methods (GBI and flossing). The primary outcome was the percentage of disagreement between the assessments in the different protocols. The data were analyzed by one-way ANOVA, McNemar, chi-square and Tukeys post hoc tests, with a 5% significance level. When gingivitis was absent in the first assessment (negative GBI), bleeding was detected in the second assessment by TF and GF in 41.7% (p < 0.001) and 50.7% (p < 0.001) of the sites, respectively. In the absence of gingivitis in the second assessment (negative GBI), TF and GF detected bleeding in the first assessment in 38.9% (p = 0.004) and 58.3% (p < 0.001) of the sites, respectively. TF and GF appears to be a better diagnostic indicator of proximal gingivitis than GBI.

CANDIDÍASE BUCAL REVISÃO DA LITERATURA

A candidiase e a infeccao micotica bucal mais comumente diagnosticada. No âmbito da Odontologia, a candidiase assume destacada importância nos pacientes portadores de aparelhos proteticos.O objetivo desta revisao da literatura e reunir os dados mais importantes sobre esta doenca, permitindo ao academico e profissional uma ampla visao sobre o assunto. Os autores abordam os fatoresetiologicos desta patologia, apresentam os tipos de manifestacoes bucais frequentes e suas caracteristicas clinicas e microscopicas, as tecnicas diagnosticas, o tratamento, o prognostico bemcomo nocoes de prevencao.