RESUMEN
Three new caryophyllane-type sesquiterpenoids, linariophyllenes A-C (1-3), two new hamamelitol derivatives, linaritols A (4) and B (5), two new chromones, linariosides A (6) and B (7), and three known chromones, cnidimol C (8), monnieriside A (9), and undulatoside A (10), were identified from the aerial parts of Evolvulus linarioides. The structures of these compounds were elucidated by NMR, MS, and IR data. The absolute configurations of compounds 1-5 and 7 were established via electronic circular dichroism data. The anti-inflammatory potential of compounds 1-5 and 7-10 was evaluated by determining their ability to inhibit the production of nitric oxide (NO) and proinflammatory cytokine IL-1ß by stimulated J774 macrophages. Compounds tested at noncytotoxic concentrations inhibited NO production by macrophages, exhibiting IC50 values between 17.8 and 66.2 µM, and inhibited IL-1ß production by stimulated macrophages by 72.7-96.2%.
Asunto(s)
Convolvulaceae/química , Componentes Aéreos de las Plantas/química , Animales , Antiinflamatorios no Esteroideos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Dicroismo Circular , Cromatografía de Gases y Espectrometría de Masas , Interleucina-1beta/antagonistas & inhibidores , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Ratones , Estructura Molecular , Óxido Nítrico/antagonistas & inhibidores , Extractos Vegetales/química , Espectrofotometría InfrarrojaRESUMEN
The generation of microstructured patterns on the surface of a specific polymeric material could radically improve their performance in a particular application. Most of the interactions with the environment occur at the material interface; therefore, increasing the exposed active surface considerably improves their range of application. In this article, a simple and reliable protocol to form spontaneous wrinkled patterns using a hydrogel layer is reported. For this purpose, we took advantage of the doctor blade technique in order to generate homogenous films over solid substrates with controlled thickness and large coverage. The hydrogel wrinkle formation involves a prepolymerization step which produces oligomers leading to a solution with increased viscosity, enough for doctor blade deposition. Subsequently, the material was exposed to vacuum and plasma to trigger wrinkled pattern formation. Finally, a UV-polymerization treatment was applied to fix the undulations on top. Interestingly, the experimental parameters allowed us to finely tune the wrinkle characteristics (period, amplitude, and orientation). For this study, two main aspects were explored. The first one is related to the role of the substrate functionalization on the wrinkle formation. The second study correlates the deswelling time and its relationship with the dimensions and distribution of the wrinkle pattern. In the first batch, four different 3-(trimethoxysilyl)propyl methacrylate (TSM) concentrations were used to functionalize the substrate in order to enhance the adhesion between hydrogel film and the substrate. The wrinkles formed were characterized in terms of wrinkle amplitude, wavelength, pattern roughness, and surface Young modulus, by using AFM in imaging and force spectroscopy modes. Moreover, the chemical composition of the hydrogel film cross-section and the effect of the plasma treatment were analyzed with confocal Raman spectroscopy. These results demonstrated that an oxidized layer was formed on top of the hydrogel films due to the exposure to an argon plasma.
Asunto(s)
Argón , Metilgalactósidos , Gases em Plasma , Argón/química , Metilgalactósidos/química , Microscopía de Fuerza Atómica , Gases em Plasma/química , Polimerizacion , Espectrometría Raman , VacioRESUMEN
An analytical liquid-liquid extraction-gas chromatography-mass spectrometry (LLE-GC-MS) method was developed and validated for the determination of trihalomethanes (THMs) in environmental samples. The compounds studied were trichloromethane (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and tribromomethane (TBM). The calibration curves for the THMs showed high linearity in the range of 1-1000 µg L-1. Studies of intra-day and inter-day precision, limit of detection (LOD), limit of quantification (LOQ), accuracy, and recovery were performed with low (10 µg L-1), medium (40 µg L-1), and high (200 µg L-1) concentrations of THMs. The intra-day and inter-day precision RSD varied in the ranges of 0.17-6.95% and 0.26-15.70%, respectively. No statistical differences were observed between the analysis of the concentration of certified reference materials (CRM 4M8140-U) and the values reported by CRM, indicating the good accuracy of the proposed method. The recovery was 88.75-119.21%. The LOD and LOQ were smaller than 0.13 and 0.40 µg L-1. Compared with reported LLE-GC-MS methods, the validated method had similar LOD and enhanced LOQ, precision, accuracy, and recovery. Also, the method is robust, selective to THMs, and the total time for the extraction and GC separation of THMs is about 18 min. The method was useful for detecting and quantifying low concentrations of TCM (40-80 µg L-1) formed by water chlorination in the presence of Microcystis aeruginosa cyanobacteria, thus demonstrating its applicability for monitoring THMs in real samples.
Asunto(s)
Monitoreo del Ambiente/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Extracción Líquido-Líquido/métodos , Trihalometanos/análisis , Contaminantes Químicos del Agua/análisis , Cloroformo/análisis , Halogenación , Microcystis/metabolismo , Agua/químicaRESUMEN
The aim of this study was to evaluate the influence of ultrasound application on the bond strength of self-adhesives resin cements to dentin. Twenty-four third molars were randomly divided into 4 groups (n = 6/group): G1 - RelyX Unicem; G2 - Maxcem Elite; G3 - RelyX Unicem and ultrasound application; G4 - Marcem Elite and ultrasound application. Composite resin blocks were luted to flat dentin with a load of 500 g for 2 min, followed by light polymerization in G1 and G2. In G3 and G4, the ultrasound device was applied for 20 s on the composite resin block, followed by 500 g load for 1 min and 40 s, and light polymerization. After storage in distilled water at 37 degrees C for 24 h, six tooth/resin sets were cut parallel to the long axis of the tooth, in the x and y directions, with a cross section area of -0.80 mm2. Twenty-four specimens were obtained for each group and submitted to microtensile bond strength (microTBS) testing in a universal testing machine at 0.5 mm/min crosshead speed. According to two-way ANOVA, resin cement (p = 0.000) and cementation method (p = 0.002) were significant. Interaction was not significant (p = 0.676). According to Student's-t test (alpha = 0.05), the microTBS mean with ultrasound application (13.74 MPa) was statistically higher than without it (10.57 MPa). The microTBS mean of RelyX Unicem (13.95 MPa) was statistically higher than Maxcem Elite (10.36 MPa). The ultrasound application increased the microTBS of the RelyX Unicem and Maxcem Elite to dentin.
Asunto(s)
Recubrimiento Dental Adhesivo , Dentina , Ensayo de Materiales , Cementos de Resina , Ultrasonografía , Humanos , Técnicas In Vitro , Tercer MolarRESUMEN
Se llevó a cabo un estudio de hemoglobinopatías en una muestra de la población infantil de la ciudad de Cartagena, analizandosa un total de 230 pacientes, 130 masculinos (56,5 por ciento) y 100 femeninos (43,4 por ciento); se encontraron 23 muestras con alteraciones en las hemoglobinas, lo que representa una frecuencia del 10 por ciento
Asunto(s)
Humanos , Niño , Hemoglobinopatías/clasificación , Hemoglobinopatías/epidemiologíaRESUMEN
Con base en 3 estudios de Malformación Congénita llevada en Popayán (1977-1978), Barranquilla (1987-1988) y Cartagena (1991-1992), se hizo un análisis de los casos encontrados de Síndrome de Down. El total de la población estudiada fue de 14.519, encontrándose 50 niños con Síndrome de Down, (incidencia de 3,3 x 1000). Se hizo un análisis de la edad materna, edad paterna, sexo, frecuencia y antecedentes de uso de anticonceptivos