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1.
Molecules ; 20(6): 10839-47, 2015 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-26111172

RESUMEN

A new natural halogen-containing stilbene derivative was isolated from the leaves of Cajanus cajan (L.) Millsp. and identified as 3-O-(3-chloro-2-hydroxyl-propanyl)-longistylin A by comprehensive spectroscopic and chemical analysis, and named cajanstilbene H (1). It is the first halogen-containing stilbene derivative found from plants. In human mesenchymal stem cells (hMSC) from bone marrow, 1 did not promote cell proliferation, but distinctly enhanced osteogenic differentiation of hMSC in time- and dose-dependent manners. In six human cancer cell lines, 1 showed a moderate inhibitory effect on cell proliferation, with IC50 values of 21.42-25.85 µmol·L(-1).


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Células Madre Mesenquimatosas/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Extractos Vegetales/administración & dosificación , Cajanus/química , Halógenos/administración & dosificación , Halógenos/química , Humanos , Extractos Vegetales/química , Hojas de la Planta/química , Estilbenos/administración & dosificación , Estilbenos/química
2.
Biosci Biotechnol Biochem ; 76(2): 404-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22313780

RESUMEN

Hot-water extracts prepared from nine out of 12 samples of dried edible Laminaria reduced the viable numbers of Aggregatibacter actinomycetemcomitans, Staphylococcus aureus, and Esherichia coli below the detection limit after incubation for 5 min when combined with lactoperoxidase, glucose oxidase, and glucose. Some extracts showed higher bactericidal activity and a higher OI(-) concentration in the assay mixture after ultrafiltration.


Asunto(s)
Antibacterianos/química , Lactoperoxidasa/farmacología , Laminaria/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Aggregatibacter actinomycetemcomitans/efectos de los fármacos , Aniones , Antibacterianos/aislamiento & purificación , Escherichia coli/efectos de los fármacos , Glucosa , Glucosa Oxidasa , Halógenos/administración & dosificación , Lactoperoxidasa/uso terapéutico , Staphylococcus aureus/efectos de los fármacos
3.
Braz Dent J ; 18(1): 54-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17639202

RESUMEN

This study evaluated the effect of blue light emitting diode (LED) and quartz tungsten halogen (QTH) on the degree of conversion (DC) of an etch-and-rinse Single Bond adhesive system (SB) and a mixture composed of primer solution and resin bond from Clearfil SE Bond self-etching adhesive system (CB) using Fourier transform infrared analysis (FTIR). Adhesives were applied to potassium bromide pellet surfaces and FTIR analyses were performed before and after photo-activation for 10 s with either LED (Freelight 1 - 400 mw/cm(2)) or QTH (XL 3000 - 630 mw/cm(2)) light-curing units (n=8). Additional FTIR spectra were obtained from photo-activated samples stored in distilled water for 1 week. The DC was calculated by comparing the spectra obtained from adhesive resins before and after photo-activation. The results were analyzed by two-way split-plot ANOVA and Tukey's test (p<0.05). Both adhesive systems exhibited low DC (%) immediately after photo-activation (SB/QTH: 18.7 +/- 3.9; SB/LED: 13.5 +/- 3.3; CF/QTH: 13.6 +/- 1.9; CF/LED: 6.1 +/- 1.0). The DC of samples light-cured with LED was lower than DC of those light-cured with QTH, immediately after light curing and after 1 week (SB/QTH: 51.3 +/- 6.6; SB/LED: 50.3 +/- 4.8; CF/QTH: 56.5 +/- 2.9; CF/LED: 49.2 +/- 4.9). The LED curing unit used to photo-activate the adhesive resins promoted lower DC than the QTH curing unit both immediately after light curing and 1 week after storage in water.


Asunto(s)
Adhesivos/efectos de la radiación , Bisfenol A Glicidil Metacrilato/efectos de la radiación , Luz , Cementos de Resina/efectos de la radiación , Adhesivos/química , Bisfenol A Glicidil Metacrilato/química , Halógenos/administración & dosificación , Cementos de Resina/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos
4.
Braz. dent. j ; Braz. dent. j;18(1): 54-59, 2007. tab, graf
Artículo en Inglés | LILACS | ID: lil-461438

RESUMEN

This study evaluated the effect of blue light emitting diode (LED) and quartz tungsten halogen (QTH) on the degree of conversion (DC) of an etch-and-rinse Single Bond adhesive system (SB) and a mixture composed of primer solution and resin bond from Clearfil SE Bond self-etching adhesive system (CB) using Fourier transform infrared analysis (FTIR). Adhesives were applied to potassium bromide pellet surfaces and FTIR analyses were performed before and after photo-activation for 10 s with either LED (Freelight 1 - 400 mw/cm²) or QTH (XL 3000 - 630 mw/cm²) light-curing units (n=8). Additional FTIR spectra were obtained from photo-activated samples stored in distilled water for 1 week. The DC was calculated by comparing the spectra obtained from adhesive resins before and after photo-activation. The results were analyzed by two-way split-plot ANOVA and Tukey's test (p<0.05). Both adhesive systems exhibited low DC ( percent) immediately after photo-activation (SB/QTH: 18.7 ± 3.9; SB/LED: 13.5 ± 3.3; CF/QTH: 13.6 ± 1.9; CF/LED: 6.1 ± 1.0). The DC of samples light-cured with LED was lower than DC of those light-cured with QTH, immediately after light curing and after 1 week (SB/QTH: 51.3 ± 6.6; SB/LED: 50.3 ± 4.8; CF/QTH: 56.5 ± 2.9; CF/LED: 49.2 ± 4.9). The LED curing unit used to photo-activate the adhesive resins promoted lower DC than the QTH curing unit both immediately after light curing and 1 week after storage in water.


Este estudo avaliou a influência de sistemas de fotoativação no grau de conversão (GC) de sistemas adesivos por meio da análise infravermelha transformada de Fourier (FTIR). Os sistemas adesivos Single Bond (SB) e Clearfil SE Bond (CF) foram aplicados em pastilhas de brometo de potássio e fotoativados com luz halógena (XL 3000 - 630 mw/cm²) (QTH) e LED (Elipar Freelight 1 - 400 mw/cm²) por 10 s (n=8). Foram obtidos espectros de FTIR antes e imediatamente após a fotoativação, e tambem após 1 semana de armazenamento em água destilada. Calculou-se o GC comparando-se a razão entre os picos das bandas dos espectros, antes e após a fotoativação. Os resultados de GC foram submetidos à ANOVA e ao teste de Tukey (p<0,05). Para ambos os sistemas adesivos, o GC ( por cento) obtido imediatamente após a fotoativação com LED foi inferior ao obtido utilizando-se QTH (SB/QTH: 18,7 ± 3,9; SB/LED: 13,5 ± 3,3; CF/QTH: 13,6 ± 1,9; CF/LED: 6,1 ± 1,0). Após uma semana foi observado um aumento significativo no GC de todos os grupos, porém os valores dos grupos fotoativados com LED mantiveram-se inferiores aos obtidos com QTH (SB/QTH: 51,3 ± 6,6; SB/LED: 50,3 ± 4,8; CF/QTH: 56,5 ± 2,9; CF/LED: 49,2 ± 4,9). O GC dos adesivos fotoativados com LED foi inferior ao observado após fotoativação com QTH, imediatamente após fotoativação como após 1 semana de armazenamento em água.


Asunto(s)
Adhesivos/efectos de la radiación , Bisfenol A Glicidil Metacrilato/efectos de la radiación , Luz , Cementos de Resina/efectos de la radiación , Adhesivos/química , Bisfenol A Glicidil Metacrilato/química , Halógenos/administración & dosificación , Cementos de Resina/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos
5.
Asunción; s.e; 20041000. 41 p. ilus.
Monografía en Español | LILACS, BDNPAR | ID: biblio-1018774

RESUMEN

Lo agentes antimicrobianos son ampliamente usados en el consultorio odontológico. Estos antimicrobianos se desarrollan cada día más, para elegir el que realmente será de utilidad, sin dañar al equipo, instrumentales pero sobre todo para no lastimar al paciente, se los deben conocer y manejarlos correctamente. La intención de este trabajo es describir agentes antimicrobianos de acción no selectiva específicamente para ser usados como agentes de desinfección, especialmente los objetos inanimados y mencionando el posible uso como agentes antisépticos. Se describirán los agentes desinfectantes de conocida efectividad, por ellos se limitarán a escribir las familias de los halógenos, fenólicis y aldehídos, sustancias que en la actualidad, son de mayor reconocimiento como agentes antimicrobianos.


Asunto(s)
Humanos , Aldehídos/administración & dosificación , Desinfección/métodos , Farmacología , Fenoles/administración & dosificación , Halógenos/administración & dosificación , Odontología
7.
Avian Dis ; 42(1): 140-5, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9533091

RESUMEN

The ability of a novel oxy-halogen formulation (OHF) to alter the development of bordetellosis (turkey coryza) in large white turkey poults was assessed. Bordetella avium (BA)-infected (1-day-of-age) and noninfected control poults received 0, 0.008%, or 0.016% of an OHF continuously in the drinking water. At 4, 7, 10, 14, and 17 days of age, reisolation of BA from infected poults was attempted. Infected poults receiving 0.016% OHF exhibited significantly lower cumulative BA reisolation rates (90%) when compared with infected poults receiving 0 (96.7%) or 0.008% OHF (100%). At 7, 14, and 17 days of age, infected poults in the OHF-treated groups were significantly heavier than those BA-challenged poults receiving control water. Feed utilization was significantly improved from hatch to 7 days of age in BA-infected poults receiving OHF when compared with infected poults receiving control water. Clinical symptoms were severe only in untreated, infected poults and were mild or absent in all others. Damage to the tracheal epithelium, as measured by scanning electron microscopy, paralleled the clinical signs. Tracheal epithelial damage was virtually eliminated by OHF administration in infected poults. These results suggest that OHF treatment ameliorates many of the symptoms frequently associated with bordetellosis in young turkeys.


Asunto(s)
Infecciones por Bordetella/veterinaria , Bordetella/patogenicidad , Halógenos/uso terapéutico , Enfermedades de las Aves de Corral , Pavos/crecimiento & desarrollo , Administración Oral , Animales , Bordetella/aislamiento & purificación , Infecciones por Bordetella/tratamiento farmacológico , Infecciones por Bordetella/prevención & control , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Células Epiteliales/ultraestructura , Halógenos/administración & dosificación , Microscopía Electrónica de Rastreo , Tráquea/patología , Abastecimiento de Agua
9.
Eisei Shikenjo Hokoku ; (110): 48-53, 1992.
Artículo en Japonés | MEDLINE | ID: mdl-1364436

RESUMEN

In the risk assessment of chemicals to humans, it is a very important step to determine no-observed-adverse-effect-levels (NOAEL) or lowest-observed-adverse-effect-levels (LOAEL) from animal experiments. Recently, short-term screening tests, such as 28-day repeated dose toxicity test, are carried out in accordance with the regulative guidelines for the safety evaluation of chemicals. However, many problems still remain in the risk assessment to human based on short-term toxicity studies. For this reason, we studied the relationships between the exposure periods and NOAELs or LOAELs in repeated dose toxicity tests using available test results of 18 halogenated compounds. The ratios between each NOAEL or LOAEL of short-term tests (14, 28 days, 13 weeks and 6 month) and those of long-term tests (longer than one year) were calculated on the basis of same animal species, route and toxic effect. From this study, it was considered that exposures above 13 weeks were needed to satisfy the present safety factor considerations for setting an acceptable daily intake (ADI).


Asunto(s)
Halógenos/toxicidad , Pruebas de Toxicidad , Administración por Inhalación , Administración Oral , Animales , Femenino , Halógenos/administración & dosificación , Masculino , Ratones , Ratas , Medición de Riesgo , Factores de Tiempo
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