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Probiotic viability, metabolite concentrations, physicochemical parameters, and volatile compounds were characterized in Gueuze beers formulated with probiotic lactic acid bacteria (LAB) and yeast. Additionally, the sensory profile of the beers and the resistance of the probiotics to digestion were determined. The use of 2 International Bitterness Units resulted in high concentrations of probiotic LAB but a decline in probiotic yeast as pH decreased. Secondary fermentation led to the consumption of maltose, citric acid, and malic acid, and the production of lactic and propionic acids. Carbonation and storage at 4 °C had minimal impact on probiotic viability. The addition of probiotic LAB resulted in a distinct aroma profile with improved sensory characteristics. Our results demonstrate that sour beers produced with probiotic LAB and a probiotic yeast, and fermented using a two-step fermentation process, exhibited optimal physicochemical parameters, discriminant volatile compound profiles, promising sensory characteristics, and high probiotic concentrations after digestion.
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Cerveja , Fermentação , Probióticos , Paladar , Compostos Orgânicos Voláteis , Cerveja/análise , Cerveja/microbiologia , Probióticos/metabolismo , Probióticos/análise , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/química , Humanos , Digestão , Lactobacillales/metabolismo , Lactobacillales/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/química , Viabilidade MicrobianaRESUMO
The aim of this research was to graft gallic acid (GA) onto high methoxyl pectin (HMP) through the redox-pair of ascorbic acid (Aa) and hydrogen peroxide (H2O2) with one- and two-pot procedures. The effectiveness of the both procedures and the chemical, physical and antioxidant properties of the obtained HMP-GA were evaluated. HMP-GAone-pot (23.3 ± 0.21 mg GA Equivalent (GAE)/g) and HMP-GAtwo-pot (32.3 ± 0.52 mg GAE/g) were best obtained at H2O2/Aa molar ratio-HMP/GA weight ratio of 9.0-0.5 and 16.0-0.5, respectively. The UV-Vis and FT-IR spectra and along with their derivative and thermal gravimetric analyses, revealed differences between HMP-GAone-pot and HMP-GAtwo-pot. The latter exhibited a greater antioxidant capacity than the former in single electron transfer (ET), hydrogen atom transfer (HAT), and ET-HAT mixed assays. The chemical differences can be attributed to side reactions that may have interfered with the grafting reaction. Consequently, HMP-GA, possessing unique antioxidant and prebiotic properties, can be synthesized through redox-pair procedures.
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Antioxidantes , Ácido Gálico , Peróxido de Hidrogênio , Oxirredução , Pectinas , Pectinas/química , Ácido Gálico/química , Antioxidantes/química , Peróxido de Hidrogênio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Ácido Ascórbico/químicaRESUMO
In recent years, antimony sulfide (Sb2S3) has been investigated as a photovoltaic absorber material due to its suitable absorber coefficient, direct band gap, extinction coefficient, earth-abundant, and environmentally friendly constituents. Therefore, this work proposes Sb2S3 film preparation by an effective two-step process using a new graphite box design and sulfur distribution, which has a high repeatability level and can be scalable. First, an Sb thin film was deposited using the RF-Sputtering technique, and after that, the samples were annealed with elemental sulfur into a graphite box, varying the sulfurization time from 20 to 50 min. The structural, optical, morphological, and chemical characteristics of the resulting thin films were analyzed. Results reveal the method's effectivity and the best properties were obtained for the sample sulfurized during 40 min. This Sb2S3 thin film presents an orthorhombic crystalline structure, elongated grains, a band gap of 1.69 eV, a crystallite size of 15.25 Å, and a nearly stoichiometric composition. In addition, the formation of a p-n junction was achieved by depositing silver back contact on the Glass/FTO/CdS/Sb2S3 structure. Therefore, the graphite box design has been demonstrated to be functional to obtain Sb2S3 by a two-step process.
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Many neurological disorders have a distinctive colonic microbiome (CM) signature. Particularly, children with autism spectrum disorders (ASD) exhibit a very dissimilar CM when compared to neurotypical (NT) ones, mostly at the species level. Thus far, knowledge on this matter comes from high-throughput (yet very expensive and time-consuming) analytical platforms, such as massive high-throughput sequencing of bacterial 16S rRNA. Here, pure (260/280 nm, ~1.85) stool DNA samples (200 ng.µL-1) from 48 participants [39 ASD, 9 NT; 3-13 y] were used to amplify four candidate differential CM markers [Bacteroides fragilis (BF), Faecalibacterium prausnitzii (FP), Desulfovibrio vulgaris (DV), Akkermansia muciniphila (AM)], using micro-organism-specific oligonucleotide primers [265 bp (BF), 198 bp (FP), 196 bp (DV), 327 bp (AM)] and a standardized two-step [low (step 1: °Tm-5 °C) to high (stage 2: °Tm-0 °C) astringent annealing] PCR protocol (2S-PCR). The method was sensitive enough to differentiate all CM biomarkers in the studied stool donors [↑ abundance: NT (BF, FP, AM), ASD (DV)], and phylogenetic analysis confirmed the primers' specificity.
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INTRODUCTION: Carious lesions have traditionally been treated by non-selective (complete or total) removal of carious tissue. However, due to its risks and adverse effects, carious tissue removal techniques have been developed, based on the preservation of tooth tissue, including the stepwise removal. The objective of this summary is to clarify the uncertainty about the effectiveness and safety of the stepwise removal technique compared to complete removal. METHODS: To answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by searching multiple sources of information, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from identified reviews, reanalyzed data from primary studies, performed a meta-analysis, and prepared summary tables of results using the GRADE method. RESULTS AND CONCLUSIONS: We identified three systematic reviews that included five primary studies, four of them corresponding to randomized trials. We concluded that stepwise removal may reduce the risk of pulp exposure, the risk of signs and symptoms of pulp disease and the risk of restoration failure, but the certainty of the evidence is low.
INTRODUCCION: Las lesiones cariosas han sido tradicionalmente tratadas mediante la remoción total (completa o no selectiva) del tejido cariado. Sin embargo, debido a sus riesgos y efectos adversos, se han desarrollado nuevas técnicas de remoción del tejido cariado, basadas en la conservación del tejido dentario, entre ellas la remoción en dos pasos o stepwise. El objetivo de este resumen es aclarar la incertidumbre sobre la efectividad y la seguridad de la técnica de remoción en dos pasos (stepwise) comparado con la remoción total. MÉTODOS: Para responder esta pregunta utilizamos Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante búsquedas en múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, reanalizamos los datos de los estudios primarios, realizamos un metaanálisis, preparamos tablas de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES: Identificamos tres revisiones sistemáticas que en conjunto incluyeron cinco estudios primarios, de los cuales cuatro corresponden a ensayos aleatorizados. Concluimos que la remoción en dos pasos (stepwise) podría disminuir el riesgo de exposición pulpar, el riesgo de aparición de signos y síntomas pulpares y la falla en la restauración, pero la certeza de la evidencia es baja.
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Cárie Dentária , Bases de Dados Factuais , Cárie Dentária/terapia , Humanos , Revisões Sistemáticas como Assunto , Resultado do TratamentoRESUMO
Today's lifespan of companies tends to be low in the so-called micro-, small-, and medium-sized enterprises (MSMEs). Organizational life cycle (OLC) theory indicates that organizational aging is related, but not determined, by the firm chronological age or its size. Therefore, a firm's aging should be analyzed by other factors such as flexibility. The literature considers flexibility as an essential capability, a source of competitive advantage, and an enabler of long-term growth for MSMEs. However, little attention in emerging economies has been paid to examine the nuances of this concept in relation to the OLC in this type of companies. Additionally, studies tend to analyze flexibility as a general term, ignoring that it is a polymorphic concept. That is why there is a need to research the different categories of flexibility. Drawing on a quantitative approach conducting a factor analysis, a two-step cluster, and decision tree analysis to interrogate data from 257 MSMEs in Mexico, this study provides evidence of different dimensions of strategic and structural flexibility that help to characterize and predict the growth, maturity, and declining stages of MSMEs. Our results show that mature firms present more strategic and structural flexible characteristics than those involved in growth or decline stages. The flexible factors that help classify and predict an MSME in the maturity stage include open communication, decentralized decision making, and formalization. We provide a model with these results to illuminate unaddressed issues regarding the broad term of flexibility and its relationship to OLC.
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INTRODUCTION AND OBJECTIVES: Implementation of a one-step strategy for diagnosis of active Hepatitis C virus (HCV) infection would encourage the early diagnosis and reduce the time to access antiviral treatments. The aim of this study was to evaluate the impact of a HCV one-step diagnosis compared to the traditional two-step protocol in terms of the time required for patients to be seen by specialists and the time taken to start antiviral treatment. MATERIAL AND METHODS: A comparative study was carried out to assess two diagnostic algorithms (one-step and two-step) for active HCV infection. Serological markers were quantified using the same serum sample to determine both anti-HCV antibodies (HCV-Ab) and HCV core antigen (HCV-cAg) by Architect i2000 SR kit. In this period, a multidisciplinary procedure was started for telematics referral of viremic patients. RESULTS: One-step approach reduced the time required for patient HCV diagnosis, referral to a specialist, access to treatment, and eliminated the loss of patients to follow-up. Significant differences were observed between one-step and two-step diagnosis methods in the time required for patients to be seen by a specialist (18 days [Interquartile range (IQR) = 14-42] versus 107 days [IQR = 62-148]) and for the initiation of treatment (54 days [IQR = 43-75] versus 200 days [IQR = 116-388]), mainly for patients with advanced fibrosis (35 days [IQR = 116-388] versus 126 days [IQR = 152-366]). CONCLUSIONS: Use of HCV-cAg has proven to be a useful tool for screening patients with active hepatitis C. The development of a multidisciplinary protocol for the communication of results improved the efficiency of the care process.
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Antivirais/uso terapêutico , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/análise , Antígenos da Hepatite C/análise , Hepatite C/diagnóstico , Telemedicina/métodos , Feminino , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos , MasculinoRESUMO
OBJECTIVES: To evaluate the performance of a two-step strategy compared with the International Ovarian Tumor Analysis (IOTA) - Assessment of Different NEoplasias in the adneXa (ADNEX) model for preoperative classification of adnexal masses. METHODS: An ambispective diagnostic accuracy study based on ultrasound data collected at one university hospital between 2012 and 2018. Two ultrasonographers classified the adnexal masses using IOTA Simple Rules (first step). Not classifiable masses were evaluated using the IOTA ADNEX model (second step). Also, all masses were classified using the IOTA ADNEX model. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), positive likelihood ratio (LR+) and negative likelihood ratio (LR-), and receiver operating characteristic (ROC) curve were estimated. A P value of <.05 was used to determine statistical significance. RESULTS: The study included 548 patients and 606 masses. Patients' median age was 41 years with an interquartile range between 32 and 51 years. In the first step, 89 (14%) masses were not classifiable. In the second step, 55 (61.8%) masses were classified as malignant. Furthermore, for the totality of 606 masses, the IOTA ADNEX model estimated the probability that 126 (20.8%) masses were malignant. The two-step strategy had a sensitivity, specificity, PPV, NPV, LR+, LR-, and ROC curve of 86.8%, 91.01%, 51.9%, 98.4%, 9.7, 0.1, and 0.889, respectively; compared to IOTA ADNEX model that had values of 91.8%, 87.16%, 44.4%, 99%, 7.1, 0.09, and 0.895, respectively. CONCLUSION: The two-step strategy shows a similar diagnostic performance when compared to the IOTA ADNEX model. The IOTA ADNEX model involves only one step and can be more practical, and thus would be recommended to use.
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Doenças dos Anexos , Neoplasias Ovarianas , Anexos Uterinos/diagnóstico por imagem , Doenças dos Anexos/diagnóstico por imagem , Adulto , Diagnóstico Diferencial , Feminino , Hospitais , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico por imagem , Sensibilidade e Especificidade , UltrassonografiaRESUMO
OBJECTIVE: To compare perinatal outcomes in pregnant women diagnosed with gestational diabetes using the one-step and the two-step test. METHODS: Meta-analysis of observational studies pregnancies women with gestational diabetes from January 2014 to February 2019. The outcomes studied were induction of labor and delivery, preterm delivery, fetal macrosomia, neonatal hypoglycemia, hyperbilirubinemia, low birth weight, and admission to the neonatal intensive care unit. RESULTS: Eight studies were included with a population of 108,609 pregnancies. Statistical differences were obtained for fetal macrosomia RR0.9 (95%CI0.85-0.97; I20%) and neonatal hypoglycemia RR1.1 (95%CI1.01-1.40; I248.5%). CONCLUSION: Neonatal macrosomia appears to be less present when the one-step diagnostic test is used and neonatal hypoglycemia was lower with the two-step test. Register PROSPERO CRD42020215062.
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Diabetes Gestacional/fisiopatologia , Macrossomia Fetal/patologia , Recém-Nascido de Baixo Peso/crescimento & desenvolvimento , Nascimento Prematuro/patologia , Feminino , Macrossomia Fetal/epidemiologia , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez , Nascimento Prematuro/epidemiologiaRESUMO
Stenting has become an important adjunctive tool for assisting coil embolization in complex-shaped intracranial aneurysms. However, as a secondary effect, stent deployment has been related to both immediate and delayed remodeling of the local vasculature. Recent studies have demonstrated that this phenomenon may assume different roles depending on the treatment stage. However, the extent of such event on the intra-aneurysmal hemodynamics is still unclear; especially when performing two-step stent-assisted coiling (SAC). Therefore, we performed computational fluid dynamics (CFD) analysis of the blood flow in four bifurcation aneurysms focusing on the stent healing period found in SAC as a two-step maneuver. Our results show that by changing the local vasculature, the intra-aneurysmal hemodynamics changes considerably. However, even though changes do occur, they were not consistent among the cases. Furthermore, by changing the local vasculature not only the shear levels change but also the shear distribution on the aneurysm surface. Additionally, a geometric analysis alone can mislead the estimation of the novel hemodynamic environment after vascular remodeling, especially in the presence of mixing streams. Therefore, although the novel local vasculature might induce an improved hemodynamic environment, it is also plausible to expect that adverse hemodynamic conditions might occur. This could pose a particularly delicate condition since the aneurysm surface remains completely exposed to the novel hemodynamic environment during the stent healing period. Finally, our study emphasizes that vascular remodeling should be considered when assessing the hemodynamics in aneurysms treated with stents, especially when evaluating the earlier stages of the treatment process.
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Aneurisma IntracranianoRESUMO
Los métodos de clasificación permiten explorar y analizar grandes conjuntos de datos visualmente, lo cual es de gran utilidad para tomar decisiones rápidas. El objetivo fue comparar dos métodos de análisis de clúster para big data en variables demográficas de las provincias del Ecuador. Se hizo uso de un estudio observacional de tipo comparativo mediante la representación simultanea del HJ-Biplot y el método Two Step (clúster bietápico), a través del software MultBiplot y SPSS. Los datos corresponden a variables demográficas de interés sociosanitarias tasa de mortalidad general, tasa de mortalidad infantil, tasa de natalidad, densidad poblacional, porcentaje urbano y esperanza de vida, medidas en las provincias del Ecuador. Se utilizaron datos provenientes del Instituto de Estadísticas y Censos INEC. Se analizó la asociación entre variables y se identificaron clústeres de las provincias del Ecuador según estas variables demográficas. Según la representación simultánea del HJ-Biplot se identificaron 3 clústeres, el clúster 1 son provincias con mayor densidad poblacional y tasas de mortalidad general, pero valores bajos de tasas de natalidad, el clúster 2 agrupa provincias con mayor esperanza de vida y tasas de mortalidad infantil pero bajos valores de tasa de natalidad y el clúster 3 están las provincias con valores altos de tasas de natalidad y valores bajos de densidad poblacional, esperanza de vida, tasas de mortalidad general y mortalidad infantil, distintos resultados se obtuvieron con el método Two Step. Se pudo concluir que estos métodos son de utilidad para explorar las similitudes entre las provincias según variables demográficas.
The classification methods allow to explore and analyze big data sets visually, which is very useful for making quick decisions. This work aimed to compare of two methods of cluster analysis for big data in demographic variables of the provinces of Ecuador. An observational study of comparative type was carried out through the simultaneous representation of the HJ/Biplot and the Two Step method (two-stage cluster), through the MultBiplot and SPSS software. The data correspond to demographic variables of socio-health interest, general mortality rate, infant mortality rate, birth rate, population density, urban percentage and life expectancy, measured in the provinces of Ecuador. Data from Statistics and Census Institute were used. The association between variables was analyzed and clusters of the provinces of Ecuador were identified according to these demographic variables. According to the simultaneous representation of the HJBiplot, 3 clusters were identified, cluster 1 are provinces with higher population density and general mortality rates, but low birth rates values, cluster 2 are provinces with higher life expectancy and mortality rates infantile but low birth rate values and cluster 3 are the provinces with high birth rates values and low population density, life expectancy, general mortality and infant mortality rates, different results were obtained with the Two Step method. It was concluded that these methods are useful for exploring the similarities between provinces according to demographic variables.
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Humanos , Análise por Conglomerados , Demografia , Modelos Estatísticos , Estatísticas Vitais , Equador/epidemiologiaRESUMO
Climbing plants are being increasingly viewed as models for bioinspired growing robots capable of spanning voids and attaching to diverse substrates. We explore the functional traits of the climbing cactus Selenicereus setaceus (Cactaceae) from the Atlantic forest of Brazil and discuss the potential of these traits for robotics applications. The plant is capable of growing through highly unstructured habitats and attaching to variable substrates including soil, leaf litter, tree surfaces, rocks, and fine branches of tree canopies in wind-blown conditions. Stems develop highly variable cross-sectional geometries at different stages of growth. They include cylindrical basal stems, triangular climbing stems and apical star-shaped stems searching for supports. Searcher stems develop relatively rigid properties for a given cross-sectional area and are capable of spanning voids of up to 1 m. Optimization of rigidity in searcher stems provide some potential design ideas for additive engineering technologies where climbing robotic artifacts must limit materials and mass for curbing bending moments and buckling while climbing and searching. A two-step attachment mechanism involves deployment of recurved, multi-angled spines that grapple on to wide ranging surfaces holding the stem in place for more solid attachment via root growth from the stem. The cactus is an instructive example of how light mass searchers with a winged profile and two step attachment strategies can facilitate traversing voids and making reliable attachment to a wide range of supports and surfaces.
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The acquisition is the most time-consuming step performed by a Global Navigation Satellite System (GNSS) receiver. The objective is to detect which satellites are transmitting and what are the phase and Doppler frequency shift of the signal. It is the step with the highest computational complexity, especially for signals subjected to large Doppler shifts. Improving acquisition performance has a large impact on the overall performance of the GNSS reception. In this paper, we present a two-step Global Positioning System (GPS) acquisition algorithm whose first step performs an incremental correlation to find a coarse pair of phase and frequency and the second step, triggered by the variance of the largest correlation values, refines the first step. The proposed strategy, based on the conventional time-domain serial algorithm, reduces the average execution time of the acquisition process to about 1/5 of the conventional acquisition while keeping the same modest logic hardware requirements and slightly better success and false-positive rates. Additionally, the new method reduces memory usage by a factor that is proportional to the signal's sampling frequency. All these advantages over conventional acquisition contribute together to significantly improve the overall performance and cost of GPS receivers.
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BACKGROUND: The geographical accessibility of health services is an important issue especially in developing countries and even more for those sharing a border as for Haiti and the Dominican Republic. During the last 2 decades, numerous studies have explored the potential spatial access to health services within a whole country or metropolitan area. However, the impacts of the border on the access to health resources between two countries have been less explored. The aim of this paper is to measure the impact of the border on the accessibility to health services for Haitian people living close to the Haitian-Dominican border. METHODS: To do this, the widely employed enhanced two-step floating catchment area (E2SFCA) method is applied. Four scenarios simulate different levels of openness of the border. Statistical analysis are conducted to assess the differences and variation in the E2SFCA results. A linear regression model is also used to predict the accessibility to health care services according to the mentioned scenarios. RESULTS: The results show that the health professional-to-population accessibility ratio is higher for the Haitian side when the border is open than when it is closed, suggesting an important border impact on Haitians' access to health care resources. On the other hand, when the border is closed, the potential accessibility for health services is higher for the Dominicans. CONCLUSION: The openness of the border has a great impact on the spatial accessibility to health care for the population living next to the border and those living nearby a road network in good conditions. Those findings therefore point to the need for effective and efficient trans-border cooperation between health authorities and health facilities. Future research is necessary to explore the determinants of cross-border health care and offers an insight on the spatial revealed access which could lead to a better understanding of the patients' behavior.
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Área Programática de Saúde , Países em Desenvolvimento , Emigração e Imigração/tendências , Acessibilidade aos Serviços de Saúde/tendências , Turismo Médico/tendências , Área Programática de Saúde/economia , Países em Desenvolvimento/economia , República Dominicana/epidemiologia , Feminino , Haiti/epidemiologia , Acessibilidade aos Serviços de Saúde/economia , Humanos , Masculino , Turismo Médico/economiaRESUMO
Background: In 1980, Reuben Andresen observed that in certain individuals, obesity did not increase mortality, introducing an atypical phenotype called "healthy obese". Other studies reported that 10-15 % of lean individuals presented insulin resistance, hyperglycemia and dyslipidemia. The objective of this study was to evaluate biochemical and clinical characteristics of metabolic phenotypes in Maracaibo city. Methods: A descriptive, cross-sectional study with a randomized multistage sampling was performed including 1226 non diabetic individuals from both sexes. For phenotype definition, the subjects were first classified according to their BMI into Normal-Weight, Overweight and Obese; then divided in metabolically healthy and unhealthy using a two-step analysis cluster. To evaluate the relationship with coronary risk, a multiple logistic regression model was performed. Results: In the studied population, 5.2% (n=64) corresponded to unhealthy lean subjects, and 17.4% (n=217) to healthy obese subjects. Metabolically unhealthy normal-weight (MUNW) phenotype was found in males in 53.3% in contrast to 51.3% of metabolically unhealthy obese (MUO) phenotype found in females. An association between metabolically unhealthy phenotypes and a higher risk of a coronary event was found, especially for obese individuals (MHO: OR=1.85 CI95%: 1.11-3.09; p=0.02 and MUO: OR=2.09 CI95%: 1.34-3.28; p<0.01). Conclusion: Individuals with atypical metabolic phenotypes exist in Maracaibo city. Related factors may include insulin resistance, basal glucose levels, and triglycerides levels. Lastly, cardiovascular risk exhibited by healthy obese individuals should be classified in categories of major coronary risk related to lean subjects.
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Plasma electrolytic oxidation (PEO) of niobium plates were done electrochemically in two steps with electrolytes containing phosphorous and calcium being observed the formation of crystalline apatite. All samples were submitted to a first step of PEO using an electrolyte containing phosphate ions. The second oxidization step was made using three different electrolytes. Some samples were oxidized by PEO in electrolyte containing calcium, while in other samples it was used two mixtures of phosphoric acid and calcium acetate monohydrate solutions. Three different surface layers were obtained. The morphology and chemical composition of the films were analyzed by scanning electronic microscopy (SEM), and energy dispersive spectroscopy (EDS) respectively. It was observed that all samples submitted to two-step oxidation shown porous surface and a calcium and phosphorus rich layer. Average surface roughness (Ra) was measured by a profilometer remaining in the sub-micrometric range. The contact angle by sessile drop technique, using 1µL of distilled water was performed with an optical goniometer. It was verified a higher hydrophilicity in all surfaces compared to the polished niobium. Orthorhombic Nb2O5 was identified by XRD in the oxide layer. Crystalline apatite was identified by XRD in surfaces after the second oxidation made with the Ca-rich electrolyte and a mixture of an electrolyte richer in Ca compared to P. These results indicate that a two-step oxidized niobium surface present great features for applications in the osseointegration processes: favorable chemical composition that increase the biocompatibility, the formation of crystalline niobium pentoxide (orthorhombic), high hydrophilicity and formation of crystalline calcium phosphate (apatite) under adequate electrolyte composition.
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Eletrólise , Apatitas , Microscopia Eletrônica de Varredura , Nióbio , Oxirredução , Propriedades de Superfície , TitânioRESUMO
Platycladus orientalis has a lifespan of several thousand years in China, making it a good plant in which to study aging at the molecular level, but this requires sufficient quantities of high-quality P. orientalis RNA. However, no appropriate methods have been reported for total RNA isolation from P. orientalis leaves. The TRIzol method did not extract RNA, while cetyltrimethylammonium bromide, sodium dodecyl sulfate-phenol, and plant RNAout kit (Tianz, Inc., China) protocols resulted in low yields of poor quality RNA. Isolating total RNA using the Spectrum Plant Total RNA Kit (Sigma-Aldrich, St. Louis, MO, USA) resulted in a high-quality product but a low yield. However, the two-step removal of polyphenols and polysaccharides in the improved plant RNAout kit protocol resulted in the isolation of RNA with a 28S:18S rRNA ratio of band intensities that was ~2:1, the A260/A280 absorbance ratio was 2.03, and the total RNA yield from P. orientalis leaves was high. This protocol was tested on different P. orientalis tissues of different ages and on leaves of five other Cupressaceae plants. The total RNAs were successfully used in complementary DNA synthesis for transcriptome sequencing and would be suitable to use in additional experiments. The results of this study will benefit future studies in Cupressaceae plants.
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RNA/isolamento & purificação , Folhas de Planta/genética , Cupressaceae/genética , Polissacarídeos , Dodecilsulfato de Sódio , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Perfilação da Expressão Gênica , Polifenóis , Sequenciamento do ExomaRESUMO
OBJECTIVES: This study evaluated the bond strength of a two-step conventional adhesive system to dentin pretreated with 2.5 % titanium tetrafluoride (TiF(4)) according to application timing (before or after acid conditioning) and primer/adhesive application method (active or passive). MATERIALS AND METHODS: Dentin surfaces were randomly treated with different adhesive procedures (n = 6): etching with phosphoric acid (PA) + primer/adhesive (Adper Single Bond 2/3M ESPE) actively applied; PA + primer/adhesive passively applied; TiF(4) before PA + primer/adhesive actively applied; TiF(4) before PA + primer/adhesive passively applied; TiF(4) after PA + primer/adhesive actively applied; and TiF(4) after PA + primer/adhesive passively applied. A composite block was built onto the tooth, which was sectioned into sticks (adhesive area of approximately 1 mm(2)). Microtensile bond strength tests and the failure mode were determined. RESULTS: Two-way ANOVA revealed no significant interaction between TiF(4) application timing and primer/adhesive application method (p = 0.184). The use of TiF(4), before or after PA significantly increased bond strength values (p < 0.001). There was no significant difference in bond strength values when using TiF4 before or after PA. The primer/adhesive application method had no influence on bond strength, regardless of whether TiF(4) was used (p = 0.906). Failure mode was predominantly adhesive. CONCLUSIONS: The use of TiF(4) promoted higher immediate bond strength to dentin. The conventional adhesive system may be applied either actively or passively, regardless of TiF(4) application timing. CLINICAL SIGNIFICANCE: Pretreatment with TiF(4) increased bond strength in a conventional two-step adhesive system to dentin, regardless of the primer/adhesive application method and the timing of dentin pretreatment.
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Colagem Dentária , Cimentos Dentários/química , Adesivos Dentinários/química , Fluoretos/química , Titânio/química , Condicionamento Ácido do Dente , Humanos , Técnicas In Vitro , Resistência à TraçãoRESUMO
La técnica de grabado ácido en esmalte representa el hito que marca la puerta de entrada para el establecimiento de la odontología adhesiva. Producto de que el sustrato adamantino pudiese presentar comportamiento refractario a la técnica convencional de grabado ácido es que se plantea una técnica en dos tiempos operatorios, la cual pudiese disminuir dicho comportamiento resistente al grabado ácido y combatir así el fenómeno de la filtración marginal de las resinas compuestas. En este estudio se utilizaron 30 terceros molares sanos, en los cuales se realizaron cavidades clases V en las caras vestibulares y linguales/palatinas, las cuales fueron obturadas con resina compuestas utilizando técnica de grabado ácido convencional y técnica de grabado ácido en dos tiempos operatorios, respectivamente. Estos especímenes fueron sometidos a un proceso de termociclado en presencia de un agente colorante marcador. Luego de un proceso de termociclado, las muestras fueron cortadas transversalmente para evaluar el porcentaje de penetración del agente marcador. El análisis de los resultados demostró que las restauraciones realizadas con técnica de grabado ácido en dos tiempos operatorios presentaron menores valores de filtración marginal, existiendo diferencias significativas entre ambos grupos estudiados.
The acid etch technique is the fact that marks the starting point for the establishment of the adhesive dentistry era. But as the enamel structure may have a resistant behavior towards the conventional acid etch technique ,a two-step acid etch technique is presented. This would diminish the aforementioned resistant behavior of enamel to the conventional acid etch technique, and minimize as well, the marginal leakage phenomenon of the composite materials. In this study 30 sound recently extracted molars were used. Equal class V cavities preparations were made in the buccal and palatal/lingual faces of each tooth. Buccal cavities were filled with composite before the use of the conventional acid etch technique, as adhesive method, while in the lingual/palatal faces the two-step acid etch technique was used. The samples were subjected to thermal cycles in the presence of a dying agent. After the thermocycling process, the samples were cut transversely to assess the percentage of penetration of the staining agent. The analysis of the results showed that there was a significant statistical difference between both groups. Moreover the restorations made with the two-step acid etch technique presented lower values of marginal leakage.
Assuntos
Humanos , Infiltração Dentária , Condicionamento Ácido do Dente/métodos , Resinas Compostas/química , Técnicas In VitroRESUMO
Mosquitoes are responsible for the transmission of pathogens that cause devastating human diseases such as malaria and dengue. The current increase in mean global temperature and changing sea level interfere with precipitation frequency and some other climatic conditions which, in general, influence the rate of development of insects and etiologic agents causing acceleration as the temperature rises. The most common strategy employed to combat target mosquito species is the Integrated Vector Management (IVM), which comprises the use of multiple activities and various approaches to preventing the spread of a vector in infested areas. IVM programmes are becoming ineffective; and the global scenario is threatening, requiring new interventions for vector control and surveillance. Not surprisingly, there is a growing need to find alternative methods to combat the mosquito vectors. The possibility of using transgenic mosquitoes to fight against those diseases has been discussed over the last two decades and this use of transgenic lines to suppress populations or to replace them is still under investigation through field and laboratory trials. As an alternative, the available transgenic strategies could be improved by coupling suppression and substitution strategies. The idea is to first release a suppression line to significantly reduce the wild population, and once the first objective is reached a second release using a substitution line could be then performed. Examples of targeting this approach against vectors of malaria and dengue are discussed.