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1.
Int. j. high dilution res ; 21(2): 15-16, May 6, 2022.
Article in English | LILACS, HomeoIndex | ID: biblio-1396738

ABSTRACT

Conventional science regards the study of UHD (highly homeopathically potentized) solutions as pseudo-science. However, an increasing number of rigorous scientific investigations demonstrate differences in physicochemical and physical characteristics of such solutions. Strictly chemically regarded, they correspond to highly distilled water. Our research team developed a system of physicochemical and UV spectrographic measurements, whereby the differences may be consistently confirmed with high statistical significance.Methods:For measurement of the physicochemical parameters,we usedpH,electrical conductivity,and oxidation-reduction potential (ORP)sensors.For UV/VIS spectroscopymeasurements,we useda Macherey-Nagelspectrophotometer.For UHD research, we used two batches of substances: Russian (R) and Brazilian (B). In R, distilled water (W) was used for dilutions and potencies as follows: potentized water (W cH9), potentized dilution of antibodies to interferon-gamma (Abs IFNγ cH9), the same original substance in the form of a mixture of potencies (Abs IFNγ cH12, cH30, cH50, shortly Abs IFNγ mix). Furthermore, we prepared higher potencies of the substances (supplementary potentiation) in a specially prepared solution and measured their characteristics. In B, the solution was used for further dilutions and potencies as follows: potentized water (W cH1) and Glyphosate potencies (Gly cH6 => cH8, cH30 => cH 32, and cH200 => cH 202).For direct or post-hoc analysis, we used Wilcoxon signed-rank test, two-tailed.Results:UV-VIS spectroscopy (R): measurements of received liquids potentized for further cH1 show statistically significant differences between all substances, except between water W and W cH9 at 260 nm. Significant differences (p-values) were as follows: Abs IFNγ mixvs. W= 0.007; Abs IFNγ mixvs.W cH9=0.008; Abs IFNγ cH9vs. W=0.044; Abs IFNγ cH9vs.W cH9= 0.026; Abs IFNγ mixvs.W cH9= 0.007; W vs.W cH9= 0.506.Physicochemical measurements:R: measurementsdemonstrated statistical difference only in pH (Abs IFNγ mix towards all others). Significant differences (p-values) were as follows: Abs IFNγ mixvs. W=0.022; Abs IFNγ mixvs.W cH9=0.005; Abs IFNγ mixvs.Abs IFNγ cH9=0.025. After supplementarypotentiation, we obtained a more conspicuous picture with many statistical differences in conductivity and ORP, ranging from p= 0.001 to 0.046.A difference between water and potentized water has also been demonstrated.B: the measurements demonstrated statistical differences mainly in pH between Gly cH8 and the rest and between Gly cH202 and W cH1.Significant differences (p-values) were as follows:Gly cH8vs. Gly cH32 =0.027; Gly cH8vs. Gly cH202 = 0.011; Gly cH8vs. W cH1= 0.014; Gly cH202vs. W cH1= 0.034.Conclusion:UV/VIS at wavelength 260 nm Abs IFNγ mix discloses a pattern similar to exclusion zone (EZ)water at 270 nm.By additional potentiation and with physicochemical measurements, we obtained higher statistical differences than in the original dilutions.In contrast, UV/VIS spectroscopy showed more conspicuous results without additional potentiation. However, the very act of succussion becomes very distinct


Subject(s)
Water/analysis , Potency , Chemical Phenomena , Photoelectron Spectroscopy
2.
Prensa méd. argent ; 108(3): 157-164, 20220000.
Article in English | LILACS, BINACIS | ID: biblio-1373258

ABSTRACT

Este artículo cubre los conceptos básicos de un nuevo modelo de homeopatía que se basa en la termodinámica química. La equivalencia entre el compuesto que causa la enfermedad en una persona saludable y el compuesto que causa la enfermedad en una persona enferma, lo que llevó a esta interpretación del nuevo modelo de homeopatía, está bien considerado. Se han considerado el mecanismo de curación, la Ley de los Similares y la Ley de los Infinitesimales. Este artículo también analiza los conceptos básicos del mecanismo de dilución y su influencia en la concentración final de moléculas de remedio en soluciones homeopáticas. El número máximo de pasos sucesivos que impliquen una molienda vigorosa y se consideró la dilución donde todavía es posible la existencia de una concentración terapéutica.


Tis article covers the basics of a new model of homeopathy that is grounded in chemical thermodynamics. Te equivalence between the disease-causing compound in a heathy person and the disease-causing compound in an ill person, which led to this interpretation of the new model of homeopathy, is well considered. Te mechanism of curing, the Law of Similars, and the Law of Infinitesimals were considered. Tis article also discusses the basics of the dilution mechanism and its influence on the final concentration of remedy molecules in homeopathic solutions. Te maximum number of succession steps involving vigorous grinding and dilution where the existence of a therapeutic concentration is still possible was considered


Subject(s)
Humans , Thermodynamics , Cure in Homeopathy/methods , Small Doses , Law of Similars/methods , Potency , Dilution/methods , Chemical Phenomena , Homeopathy/methods
3.
J. res. dent ; 10(1): 9-13, jan.-mar2022.
Article in English | LILACS, BBO | ID: biblio-1378178

ABSTRACT

Aim To evaluate physicochemical properties and semi-quantitative elemental analysis of AH Plus Jet with samples from the beginning, middle and final portions of the automix syringe system. Methodology Three experimental groups based on the source of the material used (beginning, middle and final portion) were established for each of the evaluated properties. Setting time, flow and radiopacity were evaluate following ANSI/ADA n. 57 specification. Set specimens was used in the semi-quantitative elemental analysis in an energy-dispersive X ray spectroscopy and scanning-electron microscopy (EDS/SEM). Statistical analysis was performed using one-way ANOVA followed by Tukey test (P<0.05). Results Flow, setting time, solubility and EDS/SEM tests showed no significant differences among the three portions of the automix syringe (P>0.05). Radiopacity test showed significant differences in the beginning of the syringe comparing to the middle and final portions (P<0.05). EDS/SEM analysis identified the presence of C, O, Al, Ca, Zr and W. The element Al, however, was found only in the final portion of the syringe. Conclusions The results of AH Plus Jet suggested an adequate ratio of the components, without segregation between organic and inorganic components, since the results of setting time, flow, solubility and EDS/SEM analysis presented similar values regardless of the portion of the syringe from where the sealer was taken.


Subject(s)
Humans , Root Canal Filling Materials , Solubility , Chemical Phenomena
4.
Braz. J. Pharm. Sci. (Online) ; 58: e19517, 2022. tab, graf
Article in English | LILACS | ID: biblio-1383995

ABSTRACT

Nordihydroguaiaretic acid (NDGA) is a natural product obtained by the alkaline extraction of dried plants of Larrea tridentata species. Due to the biological properties presented, such as antioxidant, anti-inflammatory, antiviral and cytotoxic capacity, this compound is being increasingly studied. In this review, it was evaluated the benefits of NDGA against different animal models. Besides that, it was found that this compound has antitumor activity similar to its synthetic derivative terameprocol in prostate tumors. The hypoglycemic effect may be evidenced by the inhibition of sugar uptake by NDGA; in obesity, studies have observed that NDGA presented a positive regulatory effect for Peroxisome proliferator-activated receptors (PPAR-α) involved in the oxidation of hepatic fatty acids and reduced the expression of lipogenic genes. Regarding its antioxidant potential, its mechanism is related to the ability to in vitro scavenging reactive substances. Although there are several studies demonstrating the benefits of using NDGA, there are also reports of its toxicity, mainly of liver damage and nephrotoxicity


Subject(s)
Masoprocol/analysis , Chemical Phenomena , Antiviral Agents/pharmacology , Plants/classification , Biological Products/analysis , In Vitro Techniques/methods , Models, Animal , Toxicity , Hypoglycemic Agents/pharmacology , Neoplasms , Antioxidants/pharmacology
5.
Acta Paul. Enferm. (Online) ; 35: eAPE00771, 2022. tab, graf
Article in Portuguese | LILACS, BDENF | ID: biblio-1364239

ABSTRACT

Resumo Objetivo Avaliar a qualidade microbiológica do leite humano pasteurizado proveniente de um Banco de Leite Humano do Estado de São Paulo. Métodos Estudo descritivo conduzido com 29 amostras de leite humano ordenhado pasteurizado (LHOP) obtidas entre julho de 2015 a março de 2016 por meio da avaliação dos registros da acidez titulável bem como da quantificação da microbiota heterotrófica (mesófilos, psicrófilos, termófilos), coliformes totais e termotolerantes, fungos filamentosos e leveduriformes e Staphylococcus spp. Realizou-se a avaliação dos parâmetros físico-químicos por meio do potencial hidrogeniônico-pH, teor energético-K e acidez Dornic-ºD. Análises estatísticas descritivas e bivariadas foram conduzidas. Resultados Evidenciou-se nas amostras a presença de psicrófilos (17,24%), termófilos (27,59%), mesófilos (55,17%), fungos filamentosos e leveduriformes (41,38%) e ausência de Staphylococcus spp. Detectou-se a presença de 82,76% de coliformes no teste presuntivo. Já no teste confirmativo VB constatou-se a presença de 54,16% de coliformes totais e no teste EC 33,33% de coliformes termotolerantes. Os valores de pH e de K não apresentaram oscilações, enquanto que, na expressão da acidez entre 3º a 15°D detectou-se crescimento microbiano. O microrganismo mesófilo, apresentou correlação positiva com variável da acidez Dornic (r=0.44;p=0.01). Conclusão A partir da avaliação da qualidade microbiológica das amostras de LHOP descartado e consideradas impróprias para consumo no referido BLH, especificamente com relação aos indicadores microbiológicos das condições de higiene, sugere que a inviabilidade das amostras possam estar associadas às boas práticas de manipulação do alimento.


Resumen Objetivo Evaluar la calidad microbiológica de la leche humana pasteurizada proveniente de un banco de leche humana del estado de São Paulo. Métodos Estudio descriptivo realizado con 29 muestras de leche humana ordeñada pasteurizada (LHOP) obtenidas entre julio de 2015 y marzo de 2016 por medio de la evaluación de los registros de acidez titulable, así como de la cuantificación de la microbiota heterótrofa (mesófilos, psicrófilos, termófilos), coliformes totales y termotolerantes, hongos filamentosos y levaduriformes y Staphylococcus spp. Se realizó la evaluación de los parámetros físico-químicos mediante el potencial de hidrógeno (pH), valor energético (K) y acidez Dornic-ºD. Se llevaron a cabo análisis descriptivos y bivariados. Resultados Se observó en las muestras la presencia de psicrófilos (17,24 %), termófilos (27,59 %), mesófilos (55,17 %), hongos filamentosos y levaduriformes (41,38 %) y ausencia de Staphylococcus spp. Se detectó la presencia del 82,76 % de coliformes en la prueba presuntiva. Por otro lado, en la prueba confirmativa VB se confirmó la presencia del 54,16 % de coliformes totales, y en la prueba EC se verificó el 33,33 % de coliformes termotolerantes. Los valores de pH y de K no presentaron oscilaciones, mientras que se detectó crecimiento microbiano en la expresión de la acidez entre 3 y 15°D. El microrganismo mesófilo presentó correlación positiva con variable de la acidez Dornic (r=0.44; p=0.01). Conclusión A partir de la evaluación de calidad microbiológica de las muestras de LHOP descartadas y consideradas inapropiadas para consumo en el BLH mencionado, especialmente respecto a los indicadores microbiológicos de las condiciones de higiene, se sugiere que la inviabilidad de las muestras pueda estar asociada con las buenas prácticas de manipulación del alimento.


Abstract Objective To assess the microbiological quality of pasteurized human milk from a Human Milk Bank in the State of São Paulo. Methods This is a descriptive study conducted with 29 pasteurized expressed human milk (PEHM) samples obtained between July 2015 and March 2016 by assessing titratable acidity records as well as quantifying heterotrophic microbiota (mesophiles, psychrophiles, thermophiles), total and thermotolerant coliforms, filamentous and yeast-like fungi and Staphylococcus spp. The physical-chemical parameters were assessed via hydrogen-pH potential, K-energy content and Dornic-ºD acidity. Descriptive and bivariate statistical analyzes were conducted. Results The presence of psychrophiles (17.24%), thermophiles (27.59%), mesophiles (55.17%), filamentous and yeast-like fungi (41.38%) and absence of Staphylococcus spp were evidenced in the sample. The presence of 82.76% of coliforms was detected in the presumptive test. In the confirmatory VB test, the presence of 54.16% of total coliforms was found and, in the EC test, we verified 33.33% of thermotolerant coliforms. The pH and K values did not show oscillations, whereas, in the expression of acidity between 3º and 15°D, microbial growth was detected. The mesophilic microorganism showed a positive correlation with the Dornic acidity variable (r=0.44; p=0.01). Conclusion Based on the microbiological quality assessment of the HMB samples discarded and considered unfit for consumption in the HMB, specifically regarding the microbiological indicators of hygiene conditions, it suggests that the infeasibility of the samples may be associated with good food handling practices.


Subject(s)
Chemical Phenomena , Pasteurization , Food Handling , Milk, Human/microbiology , Brazil , Epidemiology, Descriptive , Microbiological Techniques , Milk Banks
6.
Braz. j. oral sci ; 20: e212098, jan.-dez. 2021. ilus
Article in English | LILACS, BBO | ID: biblio-1281101

ABSTRACT

Aim: This study aimed to evaluate the pH, Ca2+ release, solubility, and antimicrobial activity of calcium hydroxide (Ca(OH)2) pastes in association with different substances. Methods: Sixty acrylic teeth (n=10) were filled with pastes that associated Ca(OH)2 with the following substances: benzalkonium chloride 5% (G1) and 50% (G2) both in propylene glycol, arnica glycolic extract (G3), green tea glycolic extract (G4), Calen/PMCC™ (G5), and Calen™ (G6). In the group G1 to G4 were used 1g of Ca(OH)2 powder with 0,8g of vehicle. pH and Ca2+ release was measured after 7, 15, and 30 days. For solubility, micro-CT was used immediately and at the periods of 7, 15, and 30 days. For the antimicrobial analysis, a biofilm of E. faecalis was induced in vitro on bovine dentin discs. Live/dead viability dye and confocal scanning microscopy were used. Results: The highest pH values occurred on the first 7 days, and the G6, G1, G3, and G5 presented the highest pH values at this period (P <0.05). Ca2+ release was higher in all groups at 7 days, with the highest values observed in G1, G5, and G6. The volume of all pastes showed no significant difference in the intragroup analysis at 7 and 15 days (P <0.05). G1 and G2 showed the highest antimicrobial action (P <0.05). For the biovolume, there was difference between the G6 and the other groups (P >0.05) with G1 presenting the lowest values. Conclusion: Benzalkonium chloride 5% increases the antimicrobial action of the Ca(OH2), without impairs physicochemical properties


Subject(s)
Root Canal Filling Materials , Calcium Hydroxide , Biofilms , Chemical Phenomena , Anti-Infective Agents
7.
Biomédica (Bogotá) ; 41(3): 555-589, jul.-set. 2021. tab, graf
Article in Spanish | LILACS | ID: biblio-1345403

ABSTRACT

Resumen En la última década se ha incrementado el número de estudios y publicaciones sobre las vesículas extracelulares y los exosomas. En Colombia, ha habido interés y avances en su estudio, lo que se evidencia en el aumento de publicaciones y proyectos de investigación. Sin embargo, este es un campo de investigación aún en desarrollo, con desafíos analíticos y limitaciones técnicas, por lo cual, en el planteamiento de los proyectos de investigación y desarrollo, es necesario considerar cuál es el estado del campo científico a nivel mundial en cuanto a la nomenclatura y la clasificación de las vesículas extracelulares, las técnicas, recursos, requisitos y especificaciones de calidad y las instituciones que regulan el campo. La respuesta a esta pregunta permitirá desarrollar estudios que cumplan con los estándares internacionales, y las exigencias y recomendaciones institucionales. Sin embargo, la información científica disponible se encuentra dispersa y no todos los aspectos son tratados a cabalidad. En este actualización se condensa la información disponible y se presentan los términos oficiales para denominar las vesículas extracelulares y la nomenclatura aceptada actualmente, así como la evolución del campo, la homogenización de los parámetros experimentales, el establecimiento de autoridades científicas, instituciones y recursos, y las recomendaciones que se han generado a nivel mundial para el desarrollo de investigaciones en vesículas extracelulares, incluidos su aislamiento, caracterización y estudio funcional. Por último, se analiza el contexto nacional de una forma crítica, teniendo en cuenta las fortalezas institucionales, los errores usualmente cometidos, y las técnicas y tecnologías analíticas disponibles.


Abstract In the last decade, the number of studies and publications on extracellular vesicles (EV) and exosomes has boomed. Colombia has displayed interest and progress in their study as shown in the increase of research project publications and products. However, this research field is still developing and has its own analytical challenges and technical limitations. For planning research projects and developing EV studies it is necessary to consider what is the state of the scientific field worldwide concerning EV nomenclature and classification, available techniques, resources, requirements and quality specifications, and the institutions that regulate the field. Answering this question will elicit EV studies that comply with international standards and respond to institutional demands and recommendations. However, the scientific information available is scattered and not all the aspects are considered in full. In this update, the available information is condensed and the official terms and currently defined nomenclature is presented, as well as the evolution of the field, the homogenization of the experimental parameters, the establishment of scientific authorities, institutions, and resources, and the recommendations generated worldwide for their development and research including their isolation, characterization, and functional studies. Finally, I analyzed the national context in a critical way, considering institutional strengths, common mistakes, and available analytical techniques and technologies.


Subject(s)
Extracellular Vesicles , Chemistry Techniques, Analytical , Resource Guide , Cell-Derived Microparticles , Exosomes , Chemical Phenomena , Terminology as Topic
8.
Rev. Asoc. Odontol. Argent ; 109(2): 137-143, ago. 2021.
Article in Spanish | LILACS | ID: biblio-1348435

ABSTRACT

El propósito de esta revisión bibliográfica es aportar información actualizada acerca de las características de los dientes bovinos en relación con su uso como sustitutos de dientes humanos en trabajos de investigación. De acuerdo con la información registrada, los dientes bovinos serían excelentes sustitutos de la dentición humana para la realización de ensayos de laboratorio con el esmalte dental como modelo experimental (AU)


The purpose of this bibliographic review is to provide updated information about the characteristics of bovine teeth to be used as substitutes for human teeth in dental research. According to the information recorded, bovine teeth appear to be excellent substitutes for human dentition for conducting laboratory tests, using dental enamel as an experimental model (AU)


Subject(s)
Cattle , Cattle , Dental Research , Dental Enamel/anatomy & histology , Tooth Erosion , Data Interpretation, Statistical , Dental Bonding , Chemical Phenomena , Dental Enamel/ultrastructure , Hardness Tests
9.
Acta amaz ; 51(2): 171-180, jun. 2021.
Article in English | LILACS | ID: biblio-1353481

ABSTRACT

Os sistemas agroflorestais (SAFs) integram, com práticas sustentáveis, culturas agrícolas e florestais para produção de madeira e alimentos, conservando os serviços ambientais e a biodiversidade. O freijó, Cordia goeldiana, tem potencial para cultivo na Amazônia para fins madeireiros, porém dados sobre as características de sua madeira em SAFs são escassas. Objetivou-se determinar as propriedades físico-mecânicas e aplicações tecnológicas da madeira de freijó produzida em um SAF multiestratificado estabelecido no estado de Rondônia, Brasil em 1996. No SAF, as espécies agrícolas e madeireiras foram estabelecidas em renques duplos no espaçamento 5,0 m x 2,5 m. Abateram-se três árvores de freijó com 19 anos de idade, para caracterização química, física (densidade e estabilidade dimensional) e mecânica (compressão, flexão estática, dureza Janka e cisalhamento) da madeira. A madeira de freijó apresentou composição química similar à de madeiras nobres tropicais, peso moderado (582,63 kg m-3) e estabilidade dimensional elevada em comparação com outras madeiras consagradas no mercado (retração longitudinal, radial e tangencial = 0,25, 4,27 e 6,83%, respectivamente). Os valores de resistência à compressão paralela (32,32 MPa) e perpendicular (8.02 MPa), resistência específica (55,32 MPa kg-1 m-3), dureza Janka paralela (2373,33 N) e perpendicular (2326,67 N), resistência à flexão estática (63,5 MPa) e ao cisalhamento (5,94 MPa) foram semelhantes aos valores observados em outras madeiras tropicais de alta densidade, produzidas em monocultivo e florestas naturais. A madeira em estudo é adequada para fabricação de produtos de alto valor agregado, como móveis finos, pisos residenciais, instrumentos musicais e peças estruturais. (AU)


Subject(s)
Wood , Ecosystem , Chemical Phenomena , Chemical Phenomena , Mechanical Tests
10.
Dent. press endod ; 11(1): 35-39, Jan-Apr2021. Tab
Article in English | LILACS | ID: biblio-1348160

ABSTRACT

Introdução: O tratamento endodôntico busca sanificar o sistema de canais radiculares para permitir adequada obturação tridimensional. Para tanto, necessita-se de materiais plásticos, como a guta-percha, associados a cimentos endodônticos com adequadas características físico-químicas. Métodos: Comparação das propriedades físico-químicas tempo de endurecimento e escoamento dos cimentos endodônticos AH Plus e Sealer Plus, de acordo com a especificação 57 da American National Standard Institute/American Dental Association para materiais obturadores. Resultados: O tempo de endurecimento do AH Plus foi de 1178 minutos e do Sealer Plus foi de 422 minutos. O escoamento do APlus foi de 3259 milímetros e do Sealer Plus, 3150 milímetros. Conclusões: O tempo de endurecimento do AH Plus foi maior quando comparado ao do cimento Sealer Plus, e não houve diferença estatística no escoamento entre os cimentos estudados (AU).


Introduction: Endodontic treatment seeks to sanitize the root canal system to allow adequate three-dimensional filling, for which plastic materials such as guttapercha are required, associated with endodontic cements with adequate physico-chemical characteristics. Methods: Comparison of the physico-chemical properties hardening and flow time of the AH Plus and Sealer Plus endodontic sealers according to the American Dental Association / American Dental Association Specification 57 for sealing materials. Results: The hardening time of the AH Plus was 1178 minutes and the Sealer Plus was 422 minutes. The AH Plus flow was 3259 millimeters and the Sealer Plus was 3150 millimeters. Conclusions: The AH Plus hardening time was higher when compared to the Sealer Plus cement and there was no statistical difference in the flow between the cements studied (AU).


Subject(s)
Humans , Root Canal Obturation , Dental Cements , Gutta-Percha , Chemical Phenomena , Dental Pulp Cavity
11.
Rev. Ateneo Argent. Odontol ; 64(1): 77-82, 2021.
Article in Spanish | LILACS | ID: biblio-1252984

ABSTRACT

A pesar de los avances e innovaciones de los materiales dentales, la microfiltración marginal y la contracción durante la polimerización continúan siendo una de las causas principales del fracaso de los tratamientos en odontología restauradora. Un sellado marginal correcto será posible cuando las fuerzas de adhesión superen las fuerzas generadas por la contracción de polimerización y las fuerzas generadas por los cambios dimensionales térmicos posteriores a la polimerización, por lo que investigaciones previas demostraron que estas limitaciones pueden ser superadas con el uso de resinas Bulk Fill como material de relleno de cavidades extensas y profundas de dientes posteriores. Estas resinas. de relleno masivo, están recibiendo atención, principalmente porque se pueden colocar, a diferencia de las resinas convencionales, en incrementos de 4 mm sin afectar la contracción de la polimerización, la adaptación de la cavidad o el grado de conversión. El objetivo de la presente revisión bibliográfica es describir la contracción de polimerización y la consecuente filtración marginal que sufren las resinas compuestas para el sector posterior Bulk Fill con base de datos de la literatura (AU)


Despite advances and innovations in dental materials, marginal microfiltration and shrinkage during polymerization continue to be one of the main causes of treatment failure in Restorative Dentistry. A correct marginal seal will be possible when the adhesion forces exceed the forces generated by polymerization contraction and the forces generated by post-polymerization thermal dimensional changes, for which previous research has shown that these limitations can be overcome with the use of Bulk Fill resins as filling material for large and deep posterior tooth cavities, these massive filling resins are receiving attention mainly because they can be placed, unlike conventional resins, in 4 mm increments without affecting polymerization shrinkage. , cavity adaptation or degree of conversion. The objective of the present bibliographic review is to describe the polymerization contraction and consequent marginal filtration suffered by Composite Resins for the Bulk Fill posterior sector with a literature database (AU)


Subject(s)
Humans , Dental Marginal Adaptation , Composite Resins , Dental Leakage , Polymerization , Materials Testing , Chemical Phenomena , Dental Cavity Preparation , Dental Restoration, Permanent/instrumentation
12.
Braz. arch. biol. technol ; 64: e21200117, 2021. tab
Article in English | LILACS | ID: biblio-1285553

ABSTRACT

Abstract This study evaluated the effects of three chemical pretreatments of biomass sorghum (BS): dilute alkaline (PTA1 and PTA2), dilute acid (PTB1 and PTB2) and alkaline hydrogen peroxide (PTC1 and PTC2) in the enzymatic hydrolysis and ethanol production. Among the six investigated conditions, the pretreatment with 7.36% H2O2 (PTC2) was the most efficient in the lignin removal and preservation of the polysaccharide fraction. After the enzymatic hydrolysis, increases in the glucose and xylose concentrations were observed in the pretreated BS hydrolysates, mainly in PTB1 and PTC1. All the hydrolysates obtained low concentrations of inhibitors. In the alcoholic fermentations with Pichia stiptis, the greatest ethanol yield was obtained in PTB1 hydrolysate (3.84 g L-1), corresponding to 16.15% of yield. The highest ethanol yield in PTB1 hydrolysate can be justified by the maximum concentration of xylose obtained in this hydrolysate, demonstrating the potential of P. stiptis in the fermentation of pentose to ethanol. The results indicated that biomass sorghum is an alternative lignocellulose source with potential for the production of second generation ethanol, opening up prospects for additional studies.


Subject(s)
Biomass , Ethanol , Chemical Phenomena , Hydrogen Peroxide , Metals, Alkali
13.
Rev. cuba. invest. bioméd ; 40(supl.1): e1450, 2021. tab
Article in Spanish | LILACS, CUMED | ID: biblio-1289473

ABSTRACT

Introducción: La Minthostachys mollises una planta aromática que crece en América Latina y produce aceites esenciales con acción antimicrobiana. Objetivo: Determinar la actividad del aceite esencial de Minthostachys mollis en diferentes concentraciones, comparado con doxiciclina y fluconazol frente a Porphyromonas gingivalis, Staphylococcus aureus y Candida albicans, a las 24, 48 y 72 horas. Métodos: Se realiza estudio experimental in vitro y longitudinal. Se prepararon 15 pocillos por subgrupo para evaluar el efecto inhibitorio de todas las concentraciones, dando un total de 360 pocillos. Por cromatografía de gases acoplada a espectrometría de masas se identificaron los componentes químicos del aceite esencial. Se analizó el efecto inhibitorio por el método de difusión de Kirby-Bauer en Agar Columbia y Agar Muller Hinton. El análisis estadístico se realizó mediante la prueba ANOVA y Tukey. Resultados: En el análisis químico se identificó principalmente pulegona (30,17 por ciento) y mentona (16,55 por ciento). Los halos de inhibición de Minthostachys mollis al 100 por ciento a las 24, 48 y 72 horas frente a la Porphyromonas gingivalis, midieron: 10,2 mm, 9,8 mm y 9,6 mm, respectivamente; frente al Staphylococcus aureus, midieron: 10,4 mm, 9,7 mm y 9,4 mm, respectivamente; y, por último, frente a Candida albicans midieron: 9,8 mm, 8,9 mm y 8,5 mm, respectivamente. Todas las concentraciones de Minthostachys mollis presentaron un efecto antimicrobiano significativamente menor que el fluconazol y la doxiciclina (p < 0,001). Conclusiones: El aceite esencial de Minthostachys mollis al 100 % presentó su mejor actividad inhibitoria frente al Staphylococcus aureus, la Porphyromonas gingivalis y la Candida albicans a las 24 horas. Sin embargo, este efecto antimicrobiano disminuye a medida que pasa el tiempo(AU)


Introduction: Minthostachys mollis is an aromatic plant species growing in Latin America which produces essential oils with antimicrobial activity. Objective: Determine the activity of essential oil from Minthostachys mollis at various concentrations as compared with doxycycline and fluconazole against Porphyromonas gingivalis, Staphylococcus aureus and Candida albicans at 24, 48 and 72 hours. Methods: An in vitro experimental longitudinal study was conducted. Fifteen wells were prepared per subgroup to evaluate the inhibitory effect of all concentrations, for a sum total of 360 wells. Chemical components of the essential oil were identified by gas chromatography-mass spectrometry. The inhibitory effect was analyzed with the Kirby-Bauer diffusion method in Mueller-Hinton and Columbia agar. Statistical analysis was based on ANOVA and Tukey's test. Results: Chemical analysis mainly found pulegone (30.17 percent) and menthone (16.55 percent). The inhibition halos of 100 percent Minthostachys mollis at 24, 48 and 72 hours against Porphyromonas gingivalis measured 10.2 mm, 9.8 mm and 9.6 mm, respectively, against Staphylococcus aureus they measured 10.4 mm, 9.7 mm and 9.4 mm, respectively, and against Candida albicans they measured 9.8 mm, 8.9 mm and 8.5 mm, respectively. The antimicrobial effect of Minthostachys mollis at all concentrations was significantly lower than that of fluconazole and doxycycline (p < 0.001). Conclusions: The essential oil from 100% Minthostachys mollis displayed its best inhibitory activity against Staphylococcus aureus, Porphyromonas gingivalis and Candida albicans at 24 hours. However, such antimicrobial effect decreases with the passing of time(AU)


Subject(s)
Humans , Male , Female , In Vitro Techniques , Oils, Volatile , Fluconazole , Analysis of Variance , Chromatography, Gas , Porphyromonas gingivalis , Gas Chromatography-Mass Spectrometry , Longitudinal Studies , Chemical Phenomena
14.
Article in English | LILACS, BBO | ID: biblio-1287481

ABSTRACT

ABSTRACT Objective: To investigate the antibacterial, mechanical, physical properties and water sorption of flowable dental composites containing 3,4-dihydropyrimidin-2(1H)-ones. Material and Methods: 3,4-dihydropyrimidin-2(1H)-ones was synthesized and the antibacterial activity of flowable dental composites containing 0-5 wt% 3,4-dihydropyrimidin-2(1H)-ones and also of their mechanical and physical properties on flowable dental composites were investigated. Flexural strength was measured by a three-point bending test. Compressive strength (CS), Water sorption (WS) and depth of cure (DOC) were investigated. The data were analyzed by One-way ANOVA test. The level of significance was determined as p<0.01. Results: The direct contact test demonstrates that by increasing the 3,4-dihydropyrimidin-2(1H)-ones content, the bacterial growth is significantly diminished (p<0.001). The average flexural strength results show that with increasing 3,4-dihydropyrimidin-2(1H)-ones until 3% in the composite, no significant difference was observed in flexural strength (p>0.001) and the mean of compressive strength results show no significant difference between 0-4% groups (p>0.001). The mean of water sorption and depth of cure results shows no significant difference between groups (p>0.001). Conclusion: Incorporation of 3,4-dihydropyrimidin-2(1H)-ones into flowable resin composites in 3% wt can reduce the activity of Streptococcus mutans.


Subject(s)
Streptococcus mutans/immunology , Microbial Sensitivity Tests , Composite Resins , Compressive Strength , Anti-Bacterial Agents/immunology , Analysis of Variance , Sorption Detoxification , Chemical Phenomena , Flexural Strength , Iran
15.
Rev. Asoc. Colomb. Cien. Biol. (En línea) ; 2(33): 46-59, 2021. graf, mapas, tab
Article in Spanish | LILACS, COLNAL | ID: biblio-1379275

ABSTRACT

Introducción: Los ríos andinos en Colombia están fuertemente influenciados por diferentes actividades antrópicas. Los macroinvertebrados han sido utilizados para evaluar la calidad del agua en estos ecosistemas. Objetivo: Este estudio analizó el comportamiento de diferentes índices basados en macroinvertebrados para evaluar la calidad del agua del tramo medio-bajo del río Jordán en Jamundí (Colombia). Materiales y métodos: Se ubicaron tres estaciones de muestreo: E1 (1173 m.s.n.m.), E2 (1069 m.s.n.m.) y E3 (1019 m.s.n.m.). Se colectaron individuos en grava, bolos y macrófitas (n=15) y se midieron las concentraciones de variables fisicoquímicas y microbiológicas (n=15). Se evaluaron los índices de calidad de agua ICA-NSF y bióticos (BMWP/Univalle, ASPT y EPT) y los índices de Shannon-Weaver, Margalef y Simpson. Se realizó una correlación de Spearman entre las matrices de similitud biótica y ambiental. Resultados: El ICA-NSF presentó variaciones espacio temporales no significativas entre las estaciones de muestreo, con calidades de agua entre "regular" y "excelente". Los índices de diversidad mostraron que la equidad y riqueza son mayores en la estación E1. El BMWP/Univalle evidenció la influencia de las diferentes actividades sobre la subcuenca del río Jordán, clasificando la estación E1 como "Buena", E2 "Aceptable" y E3 "Dudosa". Las variables que mejor explicaron el patrón de diversidad fueron las asociadas a la contaminación orgánica (DBO5 y Coliformes totales). Conclusiones: Integralmente, los índices muestran que la mejor calidad del agua se presenta en la estación E1 donde la influencia de las actividades antrópicas es menor.


Introduction: Andean rivers in Colombia are heavily influenced along the drainage basin by various human activities. Aquatic macroinvertebrates have been used in different water environments to assess water quality in rivers. Objective: This study analyzed the behavior of different biotic indices to assess water quality of the lower middle section of the Jordan River in the department of Valle del Cauca, Colombia. Materials and methods: Sampling sites were situated at different altitudes as well with different anthropogenic influences. Physicochemical and microbiological parameters (n = 15) were measured, simultaneously with biological variables. Individuals were collected in gravel, pebbles and macrophytes (n = 15) using Surber nets (0.36 m2, 500 µm) a screen net (1.6 m2, 350 µm) and a D-net (0.9 m2, 500 µm). The water quality index (NSF ICA), biotic indices BMWP/Univalle, ASPT, EPT, and the Shannon-Weaver Equity index, Margalef Diversity index and Simpson's dominance index were evaluated to determine the macroinvertebrate assemblage through sampling sites. Spearman correlation between matrices of biotic and environmental similarity, using PRIMER® software was used to determine relationship between physicochemical variables and biodiversity. Results: The water quality index ICA-NSF showed spatio-temporal variations with water qualities between "regular" and "excellent". Diversity indices showed that equity and wealth are greater at site E1, where the influence of pollution is low. Biotic indices behaved variably, BMWP/Univalle index reflected more adequately the influence of human activities of the Jordan River sub-basin. Conclusions: The variables that best explained the pattern of diversity were those associated with organic pollution (BOD5 and total coliforms).


Subject(s)
Water Quality , Statistics, Nonparametric , Chemical Phenomena
16.
Rev. Ateneo Argent. Odontol ; 63(2): 18-22, nov. 2020. ilus
Article in Spanish | LILACS | ID: biblio-1150445

ABSTRACT

El grafeno y sus derivados son muy utilizados en ciencia y tecnología por los beneficios que otorgan sus propiedades fisicoquímicas. En el área de la salud en particular, se destacan sus propiedades biológicas debido a su elevada biocompatibilidad, interacción celular y su actividad antibacteriana. La incorporación de grafeno en ciertos materiales permite obtener un material combinado con propiedades mejoradas. Un ejemplo de ello es la incorporación industrial de óxido de grafeno en metacrilato de metilo para generar un polímero (PMMA) mejorado, no solo desde el punto de vista mecánico, sino también una notoria ventaja en la respuesta biológica de los tejidos blandos. Este artículo describe el caso clínico de un paciente de 70 años, que concurrió a la consulta buscando alternativas de tratamiento para mejorar la retención y estabilidad de las prótesis para optimizar la función masticatoria, una alternativa que impacte positivamente sobre su calidad de vida. El plan de tratamiento contempló el reemplazo de las prótesis removibles por prótesis híbridas en ambos maxilares, confeccionadas con PMMA modificado industrialmente con óxido de grafeno, previa colocación de cinco implantes en cada arco (AU)


Graphene and its derivatives are widely used in science and technology due to the benefits provided by their physicochemical properties. In the health area, specifically, its biological properties stand out, due to its high biocompatibility, cellular interaction, and its antibacterial activity. The incorporation of graphene in certain materials allows obtaining a combined material with improved properties. An example of this is the industrial incorporation of graphene oxide in methyl methacrylate, to generate an improved polymer (PMMA), not only from a mechanical point of view, but also a notable advantage in the biological response of soft tissues. This article describes the clinical case of a 70-year-old patient, who attended the consultation looking for treatment alternatives to improve the retention and stability of the prostheses to optimize the masticatory function, or an alternative that had a positive impact on their quality of lifetime. The treatment plan contemplated the replacement of removable prostheses with hybrid prostheses in both jaws, made with PMMA industrially modified with graphene oxide, after placing five implants in each arch (AU)


Subject(s)
Humans , Male , Aged , Polymers , Biocompatible Materials , Methylmethacrylates/chemistry , Mouth Rehabilitation , Dental Prosthesis, Implant-Supported , Chemical Phenomena
17.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1424-1432, July-Aug. 2020. tab, graf
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1131495

ABSTRACT

Objetivou-se, com este estudo, avaliar o efeito de dietas com diferentes níveis de energia no consumo de nutrientes, na produção e na composição do leite, no peso corporal e na relação benefício:custo de uma produção de cabras leiteiras. Foram utilizadas nove cabras, distribuídas em quadrado latino triplo 3 x 3. O ensaio teve duração de 60 dias, divididos em três períodos de 20 dias. Avaliaram-se rações completas contendo três níveis de energia: 65%, 70% e 75% de NDT. Os consumos de matéria seca, proteína bruta e matéria mineral foram superiores (P<0,05) nas dietas com maiores níveis de energia em comparação à dieta com 65% de NDT. A produção de leite foi semelhante (P>0,05) nas cabras recebendo dietas contendo 70% e 75% de NDT, todavia foi superior (P<0,05) à produção de leite das cabras recebendo dieta com 65% de NDT. A dieta com 75% de NDT possibilitou maior (P<0,05) peso corporal final, quando comparada com as dietas contendo 65% e 70% de NDT. Não foi observada diferença (P>0,05) para os parâmetros físico-químicos de gordura, lactose, proteína bruta, extrato seco desengordurado, densidade, sais e condutividade do leite. Portanto, cabras alimentadas com níveis de energia entre 70% e 75% de NDT na dieta total aumentam a produção de leite, porém 75% de NDT na dieta proporciona melhor relação benefício:custo, havendo, para cada R$ 1,00 no custo investido na alimentação, R$ 1,52 de retorno financeiro.(AU)


The objective of this study was to evaluate the effect of diets with different energy levels on nutrient intake, milk production and composition, body weight and benefit:cost ratio of a dairy goat production. Nine goats were distributed in a triple 3 x 3 latin square design. The experiment lasted for 60 days, divided into three 20-day periods. Complete rations containing three energy levels were evaluated: 65%, 70% and 75% of TDN. The dry matter intake, crude protein and mineral matter consumption were higher (P <0.05) in the diets with higher levels of energy compared to the diet with 65% of TDN. Milk production was similar (P> 0.05) in goats receiving diets containing 70% and 75% TDN, but these diets produced more milk (P<0.05) than the diet with 65% of TDN. The diet with 75% of TDN allowed a higher (P<0.05) final body weight (P<0.05) when compared to diets containing 65% and 70% TDN. There was no difference (P> 0.05) in the physical-chemical parameters of fat, lactose, crude protein, defatted dry extract, density, salts and conductivity of the milk. Therefore, goats fed with diets of 70% and 75% of TDN in the total diet increased milk production. However, the diet with 75% of TDN provides a better benefit:cost ratio, as for every $ 1.00 in the cost invested, there was $ 1.52 of financial return.(AU)


Subject(s)
Animals , Body Weight , Goats , Milk/chemistry , Animal Feed/analysis , Chemical Phenomena
18.
Rev. Ateneo Argent. Odontol ; 62(1): 31-38, jun. 2020. ilus
Article in Spanish | LILACS | ID: biblio-1148166

ABSTRACT

Se analizan aspectos fármaco-tecnológicos y clínicos de biocerámicos bioabsorbibles compuestos por biovidrios con capacidad osteogénica y microbicida, para ser utilizados como relleno bioactivo en el conducto radicular y como tratamiento terapéutico en el sitio de a lesión apicoperirradicular de origen endodóntico. Mediante un diagrama ternario se consideraron las diversas variables cuyos valores determinan las diferentes fases de los vidrios bioactivos, hasta alcanzar la formación de hidroxiapatita, cuando se someten a un medio biológico. Se analizaron composición y mecanismo de acción en la reparación posendodóntica, que parte de la integración del biomaterial al tejido duro sano, sin formación de fibrosis o proceso inflamatorio inmune (AU)


Pharmacotechnological and clinical aspects of bioabsorbable bioceramics composed of bioglasses with osteogenic and microbicidal capacity are analyzed, to be used as a bioactive filler in the root canal and as a therapeutic treatment at the site of an apicoperiradicular lesion of endodontic origin. By means of a ternary diagram, the various variables whose values determine the different phases of the bioactive glasses were considered, until reaching the formation of hydroxyapatite, when subjected to a biological medium. Composition and mechanism of action were analyzed in post-endodontic repair, which starts from the integration of the biomaterial into healthy hard tissue, without the formation of fibrosis or an immune inflammatory process (AU)


Subject(s)
Biocompatible Materials , Ceramics , Durapatite , Absorbable Implants , Glass , Osteogenesis/physiology , Periapical Diseases/therapy , Wound Healing , Calcarea Silicata , Bone Substitutes , Chemical Phenomena
19.
Rev. Eugenio Espejo ; 14(1): 95-104, 20200615.
Article in Spanish | LILACS | ID: biblio-1117195

ABSTRACT

Las restauraciones dentales con técnica indirecta fueron concebidas con el propósito de optimizar las propiedades mecánicas, físicas y químicas de los materiales polimerizados. En tal sentido, se realizó una investigación cuyo objetivo fue comparar restauraciones mediante la técnica indirecta utilizando resina híbrida (P60/3M) y un cerómero (Ceramage-Shofu), a través de la resistencia flexural y la estabilidad del color. Se realizó un estudio observacional comparativo en 30 muestras estructuradas en forma de bloques, distribuidas en 2 grupos, ambos con 15 piezas, en el primero (G1) se utilizó resina Filtek P60/3M; mientras que, en el segundo (G2) se empleó cerómero marca Ceramage-Shofu. el 80,00% de las piezas del grupo 1 evolucionó de A1 a B1; sin embargo, en el grupo 2 (piezas de resina), la transformación resultó desfavorable, más del 50% alcanzó una categoría imprecisa entre los valores B3 y B4. A través de la prueba U Mann Whitney se determinó la existencia de una diferencia significativa entre ambos grupos, así como entre los estados inicial y final del color de las piezas en ambos grupos (p<0,001). La prueba t de Student permitió comparar los valores medios, obteniéndose diferencias significativas (p<0,001), en cuanto a la resistencia observada en ambos materiales odontológicos. Los resultados relativos a la resistencia flexural y la estabilidad del color entre los dos biomateriales odontológicos analizados, permitió establecer una diferencia estadísticamente significativa entre estos.


Dental restorations using indirect technique were developed to optimize the mechanical, physical and chemical properties of the polymerized materials. In this sense, this research was carried out in order to compare restorations by the indirect technique using hybrid resin (P60 / 3M) and a ceromer (Ceramage-Shofu) through flexural resistance and color stability. A comparative and observational study was carried out in 30 samples structured in the form of blocks, distributed in 2 groups, 15 pieces each one; in the first (G1) Filtek P60 / 3M resin were analyzed; while, in the second (G2), Ceramage-Shofu brand ceromer was used. 80.00% of the pieces in group 1 evolved from A1 to B1; however, in group 2 (resin pieces), the transformation was unfavorable, more than 50% selecting an imprecise category between the B3 and B4 values. The U Mann Whitney test determined the existence of a significant difference between both groups, as well as between the initial and final states of the color of the pieces in both groups (p <0.001). The Student's t-test compares the mean values, obtaining different differences (p <0.001), regarding the resistance observed in both dental materials. The results related to flexural resistance and color stability between the two dental biomaterials analyzed establish a statistically significant difference between them.


Subject(s)
Humans , Male , Female , Biocompatible Materials , Color , Dental Materials , Chemical Phenomena , Flexural Strength
20.
Biosci. j. (Online) ; 36(2): 606-618, 01-03-2020. tab, ilus
Article in English | LILACS | ID: biblio-1146428

ABSTRACT

The radish (Raphanus sativus L.) is a vegetable of the Brassicaceae family cultivated worldwide and has several medicinal properties. Its biological activities are related to various secondary metabolites present in the species, especially phenolics. Thus, the objectives of this study were the chemical analysis and evaluation of the antioxidant and antimicrobial activities of the dry extract and fractions of the fodder turnip leaves (R. sativus var. oleiferus Metzg.). Samples were analyzed by mass spectrometry and the antioxidant activity was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical method and the reducing power method. Antimicrobial activity was determined by the agar diffusion and microdilution methods. The total phenols were concentrated in the butanol fraction (121.27 mg GAE/g) and the flavonoids were concentrated in the ethyl acetate fraction (98.02 mg EQ/g). The ethyl acetate fraction showed the best antioxidants results, with 83.45% of free radical scavenging and 11.34% of ferric ions reduction. The analysis of antimicrobial activity showed that the dry extract had the highest average zone of inhibition against Bacillus subtilis (18.67 mm). Smaller values of the minimum inhibitory concentration for Micrococcus luteus were, and the ethyl acetate fraction showed a lower minimum inhibitory concentration (0.1 mg/ml) for that microorganism. There was a strong correlation between the antioxidant activity and the content of phenols and flavonoids. The results showed the potential antioxidant and antimicrobial activities of this extract with the ethyl acetate fraction being most promising for further studies.


O rabanete(Raphanus sativus L.) é um vegetal da família Brassicaceae cultivado em todo o mundo e possui diversas propriedades medicinais. Suas atividades biológicas estão relacionadas aos vários metabólitos secundários presentes na espécie, especialmente os compostos fenólicos. Desta forma, os objetivos deste estudo foram realizar análises químicas e avaliar as atividades antioxidante e antimicrobiana do extrato seco e das frações das folhas de R. sativus var. oleiferus Metzg. As amostras foram analisadas em espectrômetro de massas e o potencial antioxidante foi avaliado pelos métodos do radical DPPH (2,2-difenil-1-picrilhidrazila) e do poder redutor. A atividade antimicrobiana foi determinada pelos métodos de difusão em ágar e da microdiluição. Observou-se que os fenóis totais se concentraram na fração butanólica (121,27 mg EAG/g), enquanto que e os teores de flavonoides concentraram-se na fração acetato de etila (98,02 mg EQ/g). A fração acetato de etila apresentou os melhores resultados antioxidantes, com porcentagem de sequestro dos radicais DPPH de 83,45% e com porcentagem de redução dos íons férrico de 11,34%. A análise da atividade antimicrobiana revelou que o extrato seco teve maior média de halos de inibição frente ao Bacillus subtilis(18,67 mm). Os menores valores da concentração inibitória mínima foram para Micrococcus luteus, sendo que a fração acetato de etila demonstrou menor concentração inibitória mínima (0,1 mg/mL) para esse micro-organismo. Houve uma forte correlação entre a atividade antioxidante e o teor de fenóis e de flavonoides. Os resultados demonstraram potenciais ações antioxidante e antimicrobiana do extrato e das frações avaliados, sendo a fração acetato de etila promissora para estudos posteriores.


Subject(s)
Raphanus , Anti-Infective Agents , Antioxidants , Plants, Medicinal , Bacillus subtilis , Micrococcus luteus , Brassicaceae , Phenolic Compounds , Chemical Phenomena
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