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1.
Lett Appl Microbiol ; 75(2): 281-292, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35313037

RESUMO

Essential oils encapsulated in a polymeric matrix can be used as an alternative method to control fungi and mycotoxins. The essential oils were extracted by hydrodistillation and characterized by gas chromatography. The nanofibres were produced from poly (acid lactic) (PLA) containing essential oils by the Solution Blow Spinning method. The antifungal and antimicotoxygenic properties were evaluated against Aspergillus ochraceus and Aspergillus westerdijkiae by the fumigation method. Terpinen-4-ol (20·23%), sabinene (20·18%), 1·8-cineole (16·69%) and γ-terpinene (11·03%) were the principal compounds present in the essential oil from Alpinia speciosa, whereas citral (97·67%) was dominant from Cymbopogon flexuosus. Microscopy images showed that the addition of essential oils caused an increase in the diameter of the nanofibres. The infrared spectroscopy results indicated the presence of essential oils in the PLA nanofibres. Differential scanning calorimetry curves also indicated the existence of interactions between the essential oils and polymeric macromolecules through their plasticizing action. The hydrophobic character of nanofibres was revealed by the contact angle technique. An antifungal effect was observed, the mycelial growths (3·25-100%) and the synthesis of ochratoxin A (25·94-100%) were inhibited by the presence of the nanofibres. The results suggest that bioactive nanofibres hold promise for application to control toxigenic fungi.


Assuntos
Alpinia , Cymbopogon , Nanofibras , Óleos Voláteis , Alpinia/química , Antifúngicos/farmacologia , Aspergillus , Cymbopogon/química , Fungos , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Poliésteres
2.
Lett Appl Microbiol ; 74(5): 831-838, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35138674

RESUMO

Considering that plasmid conjugation is a major driver for the dissemination of antimicrobial resistance in bacteria, this study aimed to investigate the effects of residual concentrations of antimicrobial growth promoters (AGPs) in poultry litter on the frequencies of IncFII-FIB plasmid conjugation among Escherichia coli organisms. A 2 × 5 factorial trial was performed in vitro, using two types of litter materials (sugarcane bagasse and wood shavings) and five treatments of litter: non-treated (CON), herbal alkaloid sanguinarine (SANG), AGPs monensin (MON), lincomycin (LCM) and virginiamycin (VIR). E. coli H2332 and E. coli J62 were used as donor and recipient strains, respectively. The presence of residues of monensin, lincomycin and virginiamycin increased the frequency of plasmid conjugation among E. coli in both types of litter materials. On the contrary, sanguinarine significantly reduced the frequency of conjugation among E. coli in sugarcane bagasse litter. The conjugation frequencies were significantly higher in wood shavings compared with sugarcane bagasse only in the presence of AGPs. Considering that the presence of AGPs in the litter can increase the conjugation of IncFII-FIB plasmids carrying antimicrobial resistance genes, the real impact of this phenomenon on the dissemination of antimicrobial resistant bacteria in the poultry production chain must be investigated.


Assuntos
Anti-Infecciosos , Infecções por Escherichia coli , Saccharum , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Celulose/farmacologia , Conjugação Genética , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Lincomicina/farmacologia , Monensin , Plasmídeos/genética , Aves Domésticas/microbiologia , Virginiamicina/farmacologia
3.
Int Endod J ; 50(7): 646-651, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27400743

RESUMO

AIM: To compare the effectiveness of large apical preparations and complementary canal preparation with the Self-Adjusting File (SAF) in removing endotoxins from the root canal of teeth with apical periodontitis. METHODOLOGY: Ten single-rooted and single-canaled teeth with post-treatment apical periodontitis were selected. Endotoxin samples were taken after removal of the root filling (S1), after chemomechanical preparation (CMP) using 2.5% NaOCl and an R25 file (S2), after CMP using 2.5% NaOCl and an R40 file (S3) and after complementary CMP using the SAF system (S4). Limulus amebocyte lysate (LAL) was used to measure endotoxin levels. The Friedman and Wilcoxon tests were used to compare endotoxin levels at each clinical intervention (P < 0.05). RESULTS: After root filling removal, endotoxin was detected in 100% of the root canals (S1, 4.84 EU mL-1 ). CMP with the R25 file was able to significantly reduce endotoxin levels (P < 0.05). Increased levels of endotoxin removal were achieved by apical preparation with the R40 file (P < 0.05). Complementary CMP with SAF did not significantly reduce endotoxin levels (P > 0.05) following the use of the R40 instrument. CONCLUSIONS: Apical enlargement protocols were effective in significantly reducing endotoxin levels. Complementary preparation with the SAF system failed to eliminate residual endotoxin contents beyond those obtained with the R40 instrument.


Assuntos
Instrumentos Odontológicos , Endotoxinas/análise , Periodontite Periapical/terapia , Preparo de Canal Radicular/instrumentação , Humanos , Periodontite Periapical/microbiologia , Retratamento , Hipoclorito de Sódio/uso terapêutico
4.
Climacteric ; 19(6): 594-598, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27426988

RESUMO

Premature ovarian insufficiency has the following causes: genetic, autoimmune, metabolic, infectious, and iatrogenic dysfunctions (including radiotherapy, chemotherapy and surgery). However, premature ovarian insufficiency remains without a definite cause in a substantial number of cases. This article describes GAPO syndrome in association with premature ovarian insufficiency, as well as a novel ANTXR1 gene mutation. Histopathological study of the ovaries of a woman with hypergonadotropic hypogonadism revealed extensive deposition of hyaline extracellular material, with bilateral parenchymal atrophy and follicular depletion. Molecular study revealed a novel ANTXR1 gene mutation. The homozygous c.378 + 3A > G transition at the consensus donor splice site of intron 4 was identified. Our results support the involvement of ANTRX1 gene mutations in deregulated extracellular matrix. In addition, our study identified a novel ANTXR1 mutation causing GAPO syndrome, indicating it as a new cause of early loss of ovarian function.


Assuntos
Alopecia/complicações , Anodontia/complicações , Transtornos do Crescimento/complicações , Atrofias Ópticas Hereditárias/complicações , Insuficiência Ovariana Primária/etiologia , Adulto , Alopecia/genética , Anodontia/genética , Matriz Extracelular/patologia , Feminino , Transtornos do Crescimento/genética , Homozigoto , Humanos , Hialina , Hipogonadismo/genética , Proteínas dos Microfilamentos , Mutação , Proteínas de Neoplasias/genética , Atrofias Ópticas Hereditárias/genética , Ovário/patologia , Insuficiência Ovariana Primária/genética , Insuficiência Ovariana Primária/patologia , Receptores de Superfície Celular/genética
5.
IEEE Trans Biomed Eng ; 54(1): 162-5, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17260869

RESUMO

The design and testing of a "dry" active electrode for electroencephalographic recording is described. A comparative study between the EEG signals recorded in human volunteers simultaneously with the classical Ag-AgCl and "dry" active electrodes was carried out and the reported preliminary results are consistent with a better performance of these devices over the conventional Ag-AgCl electrodes.


Assuntos
Eletrodos , Eletroencefalografia/instrumentação , Titânio/química , Materiais Biocompatíveis/química , Impedância Elétrica , Eletroencefalografia/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Estudos de Viabilidade , Projetos Piloto
6.
Int J Oral Maxillofac Surg ; 44(3): 377-88, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25467739

RESUMO

The aim of this systematic review was to evaluate the survival and success rates of osseointegrated implants determined in longitudinal studies that conducted a follow-up of at least 10 years. A broad electronic search was conducted in MEDLINE/PubMed and the Cochrane Central Register of Controlled Trials (CENTRAL) for relevant publications in indexed journals, evaluating the clinical performance of dental implants. Using inclusion and exclusion criteria, two reviewers analyzed titles, abstracts, and complete articles, prioritizing studies of the randomized clinical trial type. A total of 23 articles were included in this review. Ten prospective studies, nine retrospective studies, and four randomized clinical trials, which evaluated 7711 implants, were selected. The mean follow-up time of the studies included was 13.4 years. All of the studies reported survival rates and mean marginal bone resorption values, with cumulative mean values of 94.6% and 1.3mm, respectively. Fourteen studies related success rates. Taking into consideration the disparate outcome measures employed to assess dental implant performance and within the limitations of this systematic review, we may affirm that osseointegrated implants are safe and present high survival rates and minimal marginal bone resorption in the long term.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Falha de Restauração Dentária , Seguimentos , Humanos , Estudos Longitudinais , Resultado do Tratamento
7.
J Chromatogr Sci ; 38(11): 469-76, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11105769

RESUMO

Seven liquid solvent systems--dichloromethane, dichloromethane-pentane (1:1), freon 113, diethyl ether-pentane (1:1 and 1:9), ethyl acetate-pentane (with and without an additional salting-out effect) (1:3 and 1:20), and seven solid-phase extraction (SPE) systems (Amberlite XAD-2, 4, 7, and 16; Porapak Q; C8; and C18)--are comparatively studied. The distribution coefficients between the extraction system and a hydroalcoholic solution (12% v/v in ethanol, pH = 3.2) of 14 selected volatile compounds belonging to different chemical families and polarities are calculated. The results are processed by factor analysis and cluster analysis, and the following conclusions are reached. First, the efficiency of extraction decreases in this order: polymeric sorbents > silica-based sorbents > liquid-liquid systems with salting-out effect approximately dichloromethane > rest of liquid solvents. Second, the addition of salt mainly increases the recovery of compounds with Lewis acid properties. Third, the efficiency of the extraction of a liquid solvent depends not only on its polarity but also on its solubility in water. Fourth, in regards to the selectivity of the SPE systems, Porapak Q is the best to extract nonpolar compounds, Amberlite XAD 4 and 16 provide the least selective extraction profiles, and C8 and C18 have a special ability to extract compounds with a Brønstedt-Lowry character. Results indicate that in all cases liquid solvents can be replaced satisfactorily by SPE systems.


Assuntos
Bebidas Alcoólicas/análise , Odorantes , Solventes , Adsorção , Cromatografia Gasosa/métodos , Concentração de Íons de Hidrogênio , Resinas Sintéticas , Sílica Gel , Dióxido de Silício , Soluções , Volatilização
8.
Arq Neuropsiquiatr ; 59(2-A): 238-41, 2001 Jun.
Artigo em Português | MEDLINE | ID: mdl-11400033

RESUMO

OBJECTIVE: to alert that use of dimethicone plus homatropine in infants up to two months, may cause episodes of transitory extrapyramidal disturbances. METHOD: report 6 infants up to two months old, in daily use of dimethicone plus homatropine, that presented typical symptoms of the basal ganglia dysfunction, characterized by repeated crisis of short duration with tonic back shift of the head (opisthotonos), deviation of the eyes upward with looking fixed and terror expression, maintained in extending hypertonia posture of the 4 members and cry and/or guttural sounds emission. RESULTS: the extrapyramidal symptoms disappeared (and did not return) after interruption of dimethicone plus homatropine. Abnormalities were not verified in neurological examination, EEG and blood tests. CONCLUSIONS: the associated dimethicone/homatropine can produce in infants with less than 2 months, basal ganglia disturbances. The differentiation of these symptoms with the widespread epileptic crisis is essential, in order to avoid the erroneous use of antiepileptic drugs.


Assuntos
Doenças dos Gânglios da Base/induzido quimicamente , Parassimpatolíticos/efeitos adversos , Simeticone/efeitos adversos , Tropanos/efeitos adversos , Cólica/tratamento farmacológico , Quimioterapia Combinada , Feminino , Humanos , Lactente , Recém-Nascido
9.
Waste Manag ; 31(2): 370-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20943365

RESUMO

Sustainable waste management system for effluents treatment sludge has been a pressing issue for pulp and paper sector. Recycling is always recommended in terms of environmental sustainability. Following an approach of waste valorisation, this work aims to demonstrate the technical viability of producing fiber-cement roof sheets incorporating cellulose primary sludge generated on paper and pulp mills. From the results obtained with preliminary studies it was possible to verify the possibility of producing fiber-cement sheets by replacing 25% of the conventional used virgin long fiber by primary effluent treatment cellulose sludge. This amount of incorporation was tested on an industrial scale. Environmental parameters related to water and waste, as well as tests for checking the quality of the final product was performed. These control parameters involved total solids in suspension, dissolved salts, chlorides, sulphates, COD, metals content. In the product, parameters like moisture, density and strength were controlled. The results showed that it is possible to replace the virgin long fibers pulp by primary sludge without impacts in final product characteristics and on the environment. This work ensures the elimination of significant waste amounts, which are nowadays sent to landfill, as well as reduces costs associated with the standard raw materials use in the fiber-cement industrial sector.


Assuntos
Celulose/química , Materiais de Construção/análise , Papel , Reciclagem/métodos , Eliminação de Resíduos/métodos , Resíduos
10.
Braz J Biol ; 70(4): 955-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21180899

RESUMO

We studied the feeding ecology of two Hylinae anurans (Hypsiboas raniceps and Scinax acuminatus), living sympatrically and syntopically in the Pantanal of Miranda, Mato Grosso do Sul State, Brazil. The two hylid species had similar relative mouth width but differed in body size. The diet of the two frog species were composed of arthropodan prey. Both species consumed 11 different prey types, of which seven were common among them. Hypsiboas raniceps had a larger niche breadth (B(A) = 0.64) than S. acuminatus (B(A) = 0.48). Trophic niche overlap among frog species was 60.7 %. Our data are suggestive that although for many anurans the diet simply tend to reflect prey availability in the microhabitat, these two frog species, despite sharing similar microhabitat and period of activity (thus potentially exposed to a similar array of preys), tends to differ somewhat in diet (about 40%) which may result from some intrinsic ecological aspects to each of them (e.g. ecophysiology) and/or differences in body size.


Assuntos
Anuros/fisiologia , Ecossistema , Comportamento Alimentar/fisiologia , Animais , Anuros/anatomia & histologia , Anuros/classificação , Artrópodes , Tamanho Corporal , Brasil , Conteúdo Gastrointestinal , Estações do Ano
11.
J Food Sci ; 72(6): S345-51, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17995689

RESUMO

A procedure for the general taste dilution analysis (TDA) of wine has been optimized and applied to characterize the tastants of 5 different wines. Samples are concentrated first by vacuum distillation at 20 degrees C to obtain a dearomatized concentrate. Such concentrate is redissolved in water and injected in a semipreparative C18-high performance liquid chromatography (HPLC) column. The effluent is separated in fractions that are collected and concentrated by vacuum distillation. Sequential dilutions of the fractions are further evaluated by a sensory panel to assess the intensity of the basic tastes and in-mouth sensations. Fractions were also submitted to HPLC-mass spectrometry (MS) analysis to screen for known tastants of wines. The Taste Dilution chromatograms showed that taste differences between wines are mainly located in fractions 1, 2, and 6, and are mainly related to bitterness and astringency. Different aspects of the method setup and of its reliability are evaluated and discussed.


Assuntos
Cromatografia Líquida de Alta Pressão/normas , Espectrometria de Massas/normas , Paladar , Vinho/análise , Vinho/classificação , Fracionamento Químico , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Sensibilidade e Especificidade , Fatores de Tempo , Vácuo
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