Synthesis and characterization of (3-Aminopropyl)trimethoxy-silane (APTMS) functionalized Gd2O3:Eu(3+) red phosphor with enhanced quantum yield.

We report the surface modification of nanocrystalline Gd2O3:Eu(3+) phosphor by (3-Aminopropyl)trimethoxysilane (APTMS). The nanoparticles were first coated with silica using the Stöber process, and then annealed at 650 °C for 2 h. Afterwards, APTMS was functionalized onto the silica layer to obtain Gd2O3:Eu(3+) nanoparticles bearing amine groups on the surface. The effect of silica coating, and the subsequent annealing process on the crystallization of the nanophosphor were analyzed by x-ray diffraction (XRD). High-resolution transmission electron microscopy (HR-TEM) confirmed the presence of a silica layer of ∼45 nm thickness. X-ray photoelectron (XPS) and Fourier transform infrared (FTIR) spectroscopy confirmed the presence of silica and the amine groups. Photoluminescence (PL) analysis demonstrated an increased emission after functionalization of nanoparticles. Absolute quantum yield (QY) measurements revealed an 18% enhancement in QY in functionalized nanoparticles compared with unmodified nanoparticles, which is of great importance for their biomedical applications.

Efecto analgésico del Lupinus mutabilis S (chocho) comparado con morfina / Analgesic effect of Lupinus mutabilis S (chocho) compared to morphine

El Lupinus mutabilis Sweet es una planta con alto contenido calórico y marcados efectos farmacológicos, por lo que pertenece al grupo de plantas nutracéuticas. Objetivo: Comparar la acción analgésica del Lupinus mutabilis S, con el de la Morfina, utilizando la técnica estandarizada de CYTED, del Plantar-test. Materiales y métodos: Utilizamos 50 ratones albinos, machos, de la cepa Holtzman, de aproximadamente 25 gramos de peso, obtenidos del bioterio del MINSA-Chorrillos, a los que previamente se les acondicionó en el bioterio de la Facultad de Medicina Humana de la Universidad San Martín de Porres y suministró alimento y agua. Se les distribuyó en cinco grupos, G1: Control negativo; G2: Lupinus mutabilis, 300 mg/kg; G3: Lupinus mutabilis, 300 mg/kg + Naloxona, 5 mg/kg; G4: Morfina, 10 mg/kg; y, G5: Morfina, 10 mg/kg + Naloxona, 5 mg/kg. Se determinó el umbral doloroso basal de cada uno de los animales en los diferentes grupos utilizando el test del Hot Plate, el mismo que se repitió a los 30, 60 y 90 ,imutos posteriores a la administración, vía intraperitoneal, de las sustancias correspondientes a cada grupo. Los resultados obtenidos fueron analizados estadisticamente con el programa Graph Pad Prism y Excel XP. Resultados: Apreciamos un efecto analgésico del Lupinus similar al de la Morfina, el mismo que fue bloqueado por Naloxona tanto en el grupo tratado con Morfina como en el tratado con Lupinus mutabilis, a la 1/2 hora. Conclusiones: El Lupinus mutabilis S, mostró un buen efecto analgésico, que al igual que la Morfina fue bloqueado por Naloxona.

Lupinus mutabilis Sweet is a plant with high calorie content and many pharmacological effects; therefore, we consider it as a nutraceutic plant. Objective: The present investigation was made with the purpose of comparing the analgesic properties of Lupinus mutabilis S with Morphine, using the standardized technique of CYTED from Plantar Test. Materials and Method: We used fifty albino mice; male of Holtzman bred weighing 25 grams approximately and got from biotherius at MINSA, Chorrillos, to whom previous conditioning in the biotherius from Facultad de Medicina Humana at Universidad de San Martin de Porres and supply of food and water, distributed in the following five groups, G1: Negative control groups, G2: Lupinus mutabilis 300 mg/kg; G3: Lupinus mutabilis, 300 mg/kg+Naloxoma, 5 mg/kg; G4: Morphine, 10 mg/kg and G5: Morphine. 10 mg/kg+Naloxona, 5 mg/kg. It was determined the basal painful threshold to each one of the animals in different groups, using the test of the Hot Plate, the same thing was repeated at 30, 60 and 90 minutus after administration by intraperitoneal via of substances according to each group. The results were analyzed statistically with the program GraphPad Prism and Excel XP. Results: We appreciate an analgesic effect of Lupinus mutabilis Sweet similar to morphine, the same that was blocked by Naloxone in both group treated with Morphine and Lupinus mutabilis at the first 30 minutes. Conclusions: Lupinus mutabilis Sweet showed a good pharmacological action, which like to Morphine that was blockaded by Naloxone.

EDC and sulfo-NHS functionalized on PVC-g-PEGMA for streptokinase immobilization.

In this work, streptokinase (SK) coenzyme was coupled onto functionalized graft copolymer poly(vinyl chloride)-g-poly(ethylene glycol)methacrylate (PEGMA) using the water soluble carbodiimide 1-ethyl-3-(3-dimethyl aminopropyl carbodiimide hydrochloride) and sulfo-N-Hydroxysulfo succinimide. Different graft values of PEGMA copolymers were prepared via preirradiation method in air by using ultraviolet light. SK was coupled onto graft copolymer and the enzyme activity was determined before and after immobilization. Surface morphology, grafting, and enzymatic activity were studied by using infrared spectroscopy, atomic force microscopy, and fluorescence microscopy. Results revealed that graft value of 0.15 provide optimum conditions to retain original SK activity, the enzyme distribution was 2.8 µg cm-2 of copolymer surface and kinetic parameters, K m and V max were 0.14 µM and 29.8 µM min-1, respectively.

Nano and micro reoriented domains and their relation with the crystal structure in the New Fe1.5Zn1.5B7O13Cl boracite.

New iron-zinc chlorine single crystals of Fe1.5Zn1.5B7O13Cl boracite were grown by chemical transport reactions in closed quartz ampoules, at a temperature of 1173 K. The crystal structure was characterized by X-ray powder diffraction (XRD) using the Rietveld refinement method and belongs to the trigonal/rombohedral system with space group R3c (No. 161). The cell parameters were a = 8.5726(1) angstroms, c = 21.0116(4) angstroms, V = 1337.26(3) angstroms3 and Z = 6. The refinement successfully proceeded and ended with sound merit figure values chi2 = 2.25, R(B) = 6.12%. Chemical analysis was performed with X-ray energy dispersive spectroscopy (EDS) and X-ray fluorescence (XRF). Ferroelectric nano and micro reoriented domains were found in this material using polarizing optical microscopy (PLM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The examination by TEM showed that in the trigonal/rombohedral system of Fe1.5Zn1.5B7O13Cl nanodomain structures exist. Thin (50-100 nm) mostly planar domains parallel to (100) were frequently observed in Fe1.5Zn1.5B7O13Cl boracite.

A new red-emitting La(1-x)Pr(x)Sr2AlO5 phosphor powder prepared by combustion synthesis.

New red luminescent powders of La(1-x)Pr(x)Sr2AlO5 (x = 0.01 at.) were prepared by the combustion synthesis method. Microstructural properties were characterized by using X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The La(1-x)Pr(x)Sr2AlO5 X-ray diffraction pattern revealed a tetragonal phase. Morphology of the grains showed nanobars with sizes of approximately 550 nm in length. Photoluminescence, cathodoluminescence and diffuse reflectance were analyzed in detail. Photoluminescence revealed two narrow emission peaks located at lambda(em1) = 497 nm (green) and lambda(em2) = 620 nm and a single maximum excitation peak of lambda(ex) = 287 nm. The cathodoluminescence spectrum confirmed the peaks detected by photoluminescence analysis. The absorbance spectrum showed broad absorption with a maximum around lambda = 280 nm, which agrees with the maximum excitation peak detected by photoluminescence.

Evaluation of the IITC tail cuff blood pressure recorder in the rat against intraarterial pressure according to criteria for human devices.

National standards govern the manufacture and marketing of medical devices in the United States, including those for indirect blood pressure measurement in man. There are no comparable standards for devices for recording in laboratory animals. Noninvasive tail cuff blood pressure (BP) recording in the rat is widely accepted, but beset by methodologic difficulties. Intraarterial recording is regarded as the "gold standard" but is invasive and also susceptible to methodologic error. We compared the IITC Mark 12 photoelectric/oscillometric tail cuff system (IITC Life Sciences, Woodland Hills, CA) versus simultaneous femoral intraarterial recordings in spontaneously hypertensive rats, during anesthesia and 1 to 2 days after recover (150 recordings under each condition), according to the guidelines for human data collection and analysis suggested the American National Standard for automated sphygmomanometers. Within- and between-observer disagreements in estimates made by two observers from 40 anesthetized recordings were less for intraarterial measurements than for the tail cuff method. Within-observer differences (mean +/- SD of differences [SDD]) for systolic, diastolic, and mean pressure were 0 +/- 1, 0 +/- 1, and 0 +/- 1 mm Hg for intraarterial versus -1 +/- 3, 0 +/- 8, and 0 +/- 5 mm Hg for tail cuff. Between-observer differences were 0 +/- 2, 0 +/- 1, and 6 +/- 2 mm Hg versus 5 +/- 4, 13 +/- 7, and 0 +/- 5 mm Hg, respectively. Differences between tail cuff and intraarterial methods were 16 +/- 13, -5 +/- 11, and 2 +/- 8 mm Hg in anesthetized animals and 8 +/- 14, -5 +/- 9, and 0 +/- 9 mm Hg in conscious animals (39% to 82% of differences exceeded 5 mm Hg). The upper limits of clinically acceptable disagreement in the American National Standard are: mean of 5 mm Hg, SDD of 8 mm Hg. The disagreement between tail cuff and intraarterial recordings cannot be ascribed to either method with certainty. These findings do not support the manufacturer's guarantee of tail-cuff readings within "5 mm Hg of intraarterial." Inaccuracy and unreliability of devices intended for laboratory animal use have considerable scientific, fiscal, and ethical implications. Marketing of these devices should also be governed by rigorous standards.