RESUMO
PURPOSE: This randomized clinical trial aimed to evaluate the postoperative sensitivity of different resin composite/adhesive materials, placed either by an incremental or bulk-fill technique in posterior resin composite replacement of amalgam restorations. METHODS AND MATERIALS: A total of 47 patients with good overall health and at least four class I or class II amalgam restorations to be replaced participated in this study. The characteristics of 188 cavities were registered and randomly restored using incremental (Z350XT, 3M) or bulk-fill (Filtek Bulk Fill, 3M; Sonic Fill, Kerr; and Opus Bulk Fill, FGM) technique. The postoperative sensitivity was assessed using a Visual Analog Scale (0-100) after 24 hours, 7 days, and 30 days. Pain scores were temporally analyzed using Friedman test followed by Dunn post hoc test (α=0.05). The frequency of tests was calculated according to the frequency and percentage of the McNemar test. RESULTS: The restorative technique and the bulk-fill system used did not affect the postoperative sensitivity, except for Filtek Bulk Fill group, which presented less postoperative sensitivity after 24 hours (p=0.037). Regardless of the restorative material, the postoperative sensitivity decreased after 24 hours, and no differences were found after 7 and 30 days. CONCLUSIONS: After 1 week, the filling technique and the bulk-fill system have no influence on the postoperative sensitivity.
Assuntos
Cárie Dentária , Restauração Dentária Permanente , Resinas Compostas/uso terapêutico , Assistência Odontológica , Materiais Dentários , Restauração Dentária Permanente/métodos , HumanosRESUMO
BACKGROUND: The chromosomal microarray analysis (CMA) is recommended as a first-tier test for individuals with developmental delay (DD)/intellectual disability (ID) and/or multiple congenital anomalies. However, owing to high costs, this technique is not widely performed for diagnostic purposes in several countries. The aim of this study was to identify clinical features that could favour the hypothesis of genomic imbalances (GIs) in individuals with DD/ID. METHODS: The sample consisted of 63 individuals, and all of them underwent a detailed evaluation by a clinical geneticist and were investigated by the CMA. They were divided into two groups. Group A composed of 20 individuals with pathogenic copy number variants (CNVs); and group B composed of 43 individuals with normal CMA results or variants of uncertain clinical significance (VUS). RESULTS: Pathogenic GIs were found in 20 cases (32%), including 11 individuals with an abnormal karyotype, VUS was found in five individuals (8%) and the results were normal in 38 individuals (60%). Major anomalies were found in 15/20 (75%) individuals in group A against 35/43 (81%) in group B. Dysmorphisms (≥5) were found in 17/20 (85%) in group A and 41/43 (95%) in group B. The most frequent major anomalies detected in group A were congenital heart disease, epilepsy and renal malformation; and in group B, they were malformations of central nervous system, congenital heart disease, microcephaly, epilepsy and hearing impairment. There was no significant statistical difference among the frequencies in groups A and B. CONCLUSIONS: Evidences point that every individual with DD/ID, with no specific clinical suspicion, should have screening for GIs as a first-tier test, regardless of the presence or absence of additional major anomalies or dysmorphisms. Future studies with a similar design would be helpful, especially in countries where the access to new technologies is still limited.
Assuntos
Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/genética , Variação Estrutural do Genoma/genética , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Fenótipo , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Análise em Microsséries , Adulto JovemRESUMO
Castor cake is a by-product of the extraction of oil from from seeds of castor plants (Ricinus communis). This by-product contains high levels of proteins, but a toxic protein, ricin, limits its use as an animal feed. Ricin can be efficiently inactivated by treatment with calcium oxide (CaO), which can be evaluated by a cytotoxicity assay using LLC-MK2 cells. The mechanism by which the CaO treatment inactivates ricin, however, is unclear. We report the structural changes responsible for ricin inactivation. Purified ricin was treated with 0.6% CaO and then analyzed by mass spectrometry. This treatment degraded the ricin at preferential sites. The aqueous CaO solution had a pH >12, which preferentially cleaved asparagine residues, followed by glutamine, serine and glycine residues. The alkaline pH affected the tertiary structure of the ricin, cleaving its polypeptide chains and thereby eliminating its cytotoxic activity.
Assuntos
Citotoxinas/toxicidade , Ricina/toxicidade , Animais , Compostos de Cálcio/farmacologia , Linhagem Celular , Óxidos/farmacologia , Proteômica , Ricina/antagonistas & inibidoresRESUMO
Dithiocarbamates are a non-systemic group of pesticides widely used to protect crops from fungal diseases. The current methodology used by monitoring laboratories to determine dithiocarbamates in food involves the analysis of CS(2) generated after hydrolysis of the compound present in the sample. This method does not identify the origin of the CS(2) detected, which may or may not be related to the presence of pesticides leading to a potential overestimation of the dietary dithiocarbamate intake. In this paper, 520 food samples (papaya, banana, apple, strawberry, orange, potato, tomato, rice and dry beans) collected in the local market of the Federal District, Brazil, were analyzed for dithiocarbamate content. Detectable levels (> or =10.10 mg/kg CS(2)) were found in 60.8% of the samples, with the highest levels (up to 3.8 mg/kg) found in strawberry, papaya and banana. No residues were found in rice (polished) and only one dry bean sample had detectable levels of the fungicides. Detectable residues were found in the pulp of banana, papaya (including the seeds) and orange (50-62% of the analyzed samples). An exposure assessment, based on dithiocarbamate levels detected in the food crops analyzed in this study, confirms that the intake of dithiocarbamates through food consumption in the country does not represent a health risk to consumers, i.e., the estimated daily intake is less than the acceptable daily intake. Furthermore, the implementation of more selective methodologies to individually analyze these compounds in food monitoring programs in Brazil is not necessary.
Assuntos
Qualidade de Produtos para o Consumidor , Etilenobis (ditiocarbamatos)/análise , Contaminação de Alimentos/análise , Fungicidas Industriais/análise , Resíduos de Praguicidas/análise , Brasil , Produtos Agrícolas/química , Etilenobis (ditiocarbamatos)/toxicidade , Análise de Alimentos , Fungicidas Industriais/toxicidade , Humanos , Concentração Máxima Permitida , Resíduos de Praguicidas/toxicidade , Medição de RiscoRESUMO
AIMS: The thermal stability of isolated and extracted recombinant green fluorescent protein (GFPuv) was evaluated by analysing the loss of fluorescence intensity. METHODS AND RESULTS: GFPuv was expressed by Escherichia coli, extracted by the three-phase partitioning method and purified by elution through an hydrophobic interaction column. The collected fractions were further diluted in Tris-HCl-EDTA (pH 8.0) and subjected to continuous heating at set temperatures (45-95 degrees C). From a standard curve relating fluorescence intensity to GFPuv concentration, the loss of fluorescence intensity was converted to denatured GFPuv concentration (microg ml-1). To determine the extent of the thermal stability of GFPuv, decimal reduction times (D-values), z-value and energy of activation (Ea) were calculated. CONCLUSIONS: For temperatures between 45 and 70 degrees C, extracted native GFPuv activity decreased from 11 to 75% relative to initial native protein concentration above 70 degrees C, the average decrease in GFPuv fluorescence was between 72 to 83%. SIGNIFICANCE AND IMPACT OF THE STUDY: The thermal stability of GFPuv provides the basis for its potential utility as a fluorescent biological indicator to assess the efficacy of the treatment of liquids and materials exposed to steam.
Assuntos
Proteínas Luminescentes/química , Proteínas Recombinantes/química , Clonagem Molecular , Escherichia coli/genética , Fluorescência , Proteínas de Fluorescência Verde , Temperatura Alta , Indicadores e Reagentes , Cinética , Proteínas Luminescentes/isolamento & purificação , Desnaturação Proteica , Proteínas Recombinantes/isolamento & purificação , Temperatura , Fatores de Tempo , Transformação BacterianaRESUMO
Dithiocarbamates are a class of fungicides extensively used in many crops worldwide. The current residue definition of dithiocarbamates in food for compliance with maximum residue limits, at national and international levels, is total residues arising from the use of any or each dithiocarbamate fungicide, determined as CS(2). The analytical method most frequently used to analyze dithiocarbamate residues in food for monitoring purposes was proposed more than 30 years ago. In this method, total dithiocarbamates are decomposed to CS(2), which is purified and reacted with a cupric reagent. The yellow complex formed is quantified by spectrophotometry. In this paper, a new reaction system for the purification and complexation of CS(2) is proposed. The new system is less fragile than the traditional design, is easier to assemble, and allows for a higher sample throughput, in addition to being of low cost. Recovery of added mancozeb, thiram, or ziram (0.15-8.0 mg/kg) in rice, beans, apple, banana, orange, papaya, tomato, cucumber, and potato ranged from 82 to 120%, with relative standard deviations from 0 to 10% (n = 3 or 5). Analysis of apple, tomato, and papaya samples with field-incurred dithiocarbamate residues showed comparable results using both the traditional and the new reaction systems.
Assuntos
Dissulfetos/química , Etilenobis (ditiocarbamatos)/análise , Análise de Alimentos/métodos , Fungicidas Industriais/análise , Resíduos de Praguicidas/análise , Espectrofotometria/métodos , Fabaceae/química , Frutas/química , Oryza/química , Verduras/químicaRESUMO
BACKGROUND: Chronic hypoxia has been shown to modulate nitric oxide (NO) responses in different cell models, but the relationship between hypoxia and NO synthase (NOS) regulation in humans was not studied. We studied the relationship between endothelial and inducible NOS (eNOS and iNOS) activities and expression and chronic hypoxia in children with cyanotic and acyanotic congenital heart defects. METHODS AND RESULTS: Right atrial tissue was excised from 18 patients during cardiac surgery. eNOS and iNOS activities were measured by conversion of L-[H(3)]arginine to L-[H(3)]citrulline. Gene expression of eNOS and iNOS was quantified by competitive reverse transcription-polymerase chain reaction. The eNOS activity and expression were significantly reduced in cyanotic hearts compared with acyanotic hearts: 0.38+/-0.14 versus 1.06+/-0.11 pmol. mg(-1). min(-1) (P<0.0001) and 0.54+/-0.08 versus 0.80+/-0.10 relative optical density (ROD) of cDNA (P<0.0001), respectively. In contrast, iNOS activity and expression were significantly higher in cyanotic than in acyanotic children: 7.04+/-1.20 versus 4.17+/-1.10 pmol. mg(-1). min(-1) (P<0.0001) and 2.55+/-0.11 versus 1.91+/-0.18 ROD of cDNA (P<0.0001), respectively. CONCLUSIONS: Hypoxia downregulates eNOS activity and gene expression in cardiac tissue from patients with cyanotic congenital heart defects. By contrast, iNOS activity and expression are increased in cyanotic children and may represent an alternative mechanism to counteract the effects of hypoxia in the cardiovascular system. Therefore, a novel adaptive mechanism during hypoxia is suggested.
Assuntos
Cianose/enzimologia , Cardiopatias Congênitas/enzimologia , Hipóxia/enzimologia , Óxido Nítrico Sintase/metabolismo , Adaptação Fisiológica , Adolescente , Apêndice Atrial/enzimologia , Gasometria , Criança , Pré-Escolar , Cianose/etiologia , Regulação para Baixo , Feminino , Expressão Gênica , Átrios do Coração/enzimologia , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/cirurgia , Hemodinâmica , Humanos , Lactente , Recém-Nascido , Masculino , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
OBJECTIVE: To conduct a chronic dietary risk assessment of the pesticides registered in Brazil up until 1999. METHODS: The Theoretical Maximum Daily Intake (TMDI) for each pesticide was calculated using the Brazilian maximum residue limits and food consumption data from IBGE, the Brazilian Statistical Institute. The risk characterization was done comparing the TMDI with the acceptable daily intakes (ADI) from other countries and from the Codex Alimentarius. RESULTS: The TMDI was higher than the ADI (%ADI>100) at least in one Brazilian metropolitan region for 23 pesticides. Sixteen compounds are organophosphate insecticides, with methyl parathion having the TMDI exceeding the most toxicological parameter (%ADI N=9,300). Rice, beans, citrus and tomato were the commodities which most contributed to the ingestion. From the compounds under higher risk, only 6 were registered according to the Law 98.816/90, which concerns the use of pesticides in the country. CONCLUSIONS: The compounds identified in the study as presenting a potential health concern to the Brazilian consumers, and the commodities which most contributed to the ingestion, should be prioritized by the government in pesticide residue monitoring programs and in the re-registration process. In addition, residue data in food as consumed, processing factors and appropriate consumption data should be generated to allow further studies.
Assuntos
Análise de Alimentos , Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Brasil , Humanos , Concentração Máxima Permitida , Resíduos de Praguicidas/intoxicação , Medição de RiscoRESUMO
The pH and calcium ion release of three root canal sealers--Sealapex, Sealer 26, and Apexit--were assessed at 24 and 48 hr, and at 7 and 30 days after spatulation. After manipulation, the sealers were placed in 1-cm-long tubes measuring 4 mm in diameter and immersed in a glass flask containing 10 ml of deionized water, which was hermetically sealed and stored at 37 degrees C. The tubes were removed at the scheduled times and the water in which they were immersed was tested for pH with a pHmeter and for released calcium by atomic absorption spectrophotometry. Starting 48 hr after immersion, Selapex produced an alklaine pH and released significantly higher calcium amounts compared with the other two sealers, with even more pronounced results after 30 days. On the basis of the results obtained, we conclude that Sealapex presented the highest calcium and hydroxyl release, especially after longer time intervals, whereas Sealer 26 showed highest release during the initial periods (i.e. during its setting time). Apexit presented the least satisfactory results.
Assuntos
Materiais Restauradores do Canal Radicular/química , Análise de Variância , Bismuto/química , Cálcio/química , Hidróxido de Cálcio/química , Concentração de Íons de Hidrogênio , Radical Hidroxila/química , Teste de Materiais , Salicilatos/química , Estatísticas não ParamétricasRESUMO
The flexible approach to tympanoplasty has been found to be adaptable to various forms of pathologic conditions found in the temporal bone, including inflammation and infection, congenital stenosis, benign and malignant tumors, and traumatic injuries. This approach finds its best indication among all pathologic conditions in the temporal bone, in the surgical treatment of otitis media, and its sequelae. A procedure conceived to treat this dynamic process must be adaptable to new circumstances and new findings and be ready to manage unexpected situations. The flexible tympanoplasty is a step-wise approach designed to explore the contents of the middle ear methodically and in the process disclose, confirm, and often treat disease.