New Nanostructured Silica Adjuvant (SBA-15) Employed to Produce Antivenom in Young Sheep Using Crotalus durissus terrificus and Apis mellifera Venoms Detoxified by Cobalt-60

Equine antivenom is considered the only treatment for animal-generated envenomations, but it is costly. The study aimed to produce Apis mellifera (Africanized honeybee) and Crotalus durissus terrificus (C.d.t.) antivenoms using nanostructured silica (SBA-15) as adjuvant and cobalt-60 (60Co)-detoxified venoms utilizing young sheep. Natural and 60Co-irradiated venoms were employed in four different hyperimmunization protocols. Thus, 8 groups of 60- to 90-d-old sheep were hyperimmunized, enzyme-linked immunosorbent assay (ELISA) serum titers collected every 14 d were assessed clinically daily, and individual weight were measured, until d 84. Incomplete Freund's (IFA) and nanostructured silica (SBA15) adjuvants were compared. The lethal dose (LD50) for both venoms was determined following intraperitoneal (ip) administration to mice. High-performance liquid chromatography on reversed phase (HPLC-RP) was used also to measure the 60Co irradiation effects on Apis venom. At the end of the study, sheep were killed in a slaughterhouse. Kidneys were histologically analyzed. LD50 was 5.97 mg/kg Apis and 0.07 mg/kg C.d.t. for native compared to 13.44 mg/kg Apis and 0.35 mg/kg C.d.t. for irradiated venoms. HPLC revealed significant differences in chromatographic profiles between native and irradiated Apis venoms. Native venom plus IFA compared with SBA-15 showed significantly higher antibody titers for both venoms. Apis-irradiated venom plus IFA or SBA-15 displayed similar antibody titers but were significantly lower when compared with native venom plus IFA. Weight gain did not differ significantly among all groups. 60Co irradiation decreased toxicity and maintained venom immunogenic capacity, while IFA produced higher antibody titers. SBA-15 was able to act as an adjuvant without producing adverse effects. Hyperimmunization did not affect sheep weight gain, which would considerably reduce the cost of antiserum production, as these sheep were still approved for human consumption even after being subjected to hyperimmunization.

Genetic Responses to Nanostructured Calcium-phosphate-coated Implants

Nanostructured calcium phosphate (CaP) has been histologically and biomechanically proven to enhance osseointegration of implants; however, conventional techniques were not sufficiently sensitive to capture its biological effects fully. Here, we compared the conventional removal torque (RTQ) evaluation and gene expression in tissues around nanostructured CaP-coated implants, using real-time RT-PCR, with those of uncoated implants, in a rabbit model. At 2 wks, RTQ values were significantly higher, alkaline phosphatase (ALP) expression was significantly higher, and runt-related transcription factor 2 and tumor necrosis factor-alpha expressions were significantly lower in the coated than in the uncoated implants. This indicates that inflammatory responses were suppressed and osteoprogenitor activity increased around the CaP-coated surface. At 4 wks, although RTQ values did not significantly differ between the 2 groups, ALP and osteocalcin (OCN) were significantly up-regulated in the coated group, indicating progressive mineralization of the bone around the implant. Moreover, an osteoclast marker, adenosine triphosphatase, which indicates acidification of the resorption lacunae, was significantly higher for the coated implants, suggesting gradual resorption of the CaP coating. This study reveals detailed genetic responses to nanostructured CaP-coated implants and provides evidence that the effect of nanotopography is significant during the osseointegration cascade.

Histological and three-dimensional evaluation of osseointegration to nanostructured calcium phosphate-coated implants

Nanostructures on implant surfaces have been shown to enhance osseointegration; however, commonly used evaluation techniques are probably not sufficiently sensitive to fully determine the effects of this process. This study aimed to observe the osseointegration properties of nanostructured calcium phosphate (CaP)-coated implants, by using a combination of three-dimensional imaging and conventional histology. Titanium implants were coated with stable CaP nanoparticles using an immersion technique followed by heat treatment. Uncoated implants were used as the control. After topographical and chemical characterizations, implants were inserted into the rabbit femur. After 2 and 4 weeks, the samples were retrieved for micro-computed tomography and histomorphometric evaluation. Scanning electron microscopy evaluation indicated that the implant surface was modified at the nanoscale by CaP to obtain surface textured with rod-shaped structures. Relative to the control, the bone-to-implant contact for the CaP-coated implant was significantly higher at 4 weeks after the implant surgery. Further, corresponding 3-D images showed active bone formation surrounding the implant. 3-D quantification and 2-D histology demonstrated statistical correlation; moreover, 3-D quantification indicated a statistical decrease in bone density in the non-coated control implant group between 2 and 4 weeks after the surgery. The application of 3-D evaluation further clarified the temporal characteristics and biological reaction of implants in bone. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Influence of rare earth doping on the structural and catalytic properties of nanostructured tin oxide

Nanoparticles of tin oxide, doped with Ce and Y, were prepared using the polymeric precursor method. The structural variations of the tin oxide nanoparticles were characterized by means of nitrogen physisorption, carbon dioxide chemisorption, X-ray diffraction, and X-ray photoelectron spectroscopy. The synthesized samples, undoped and doped with the rare earths, were used to promote the ethanol steam reforming reaction. The SnO2-based nanoparticles were shown to be active catalysts for the ethanol steam reforming. The surface properties, such as surface area, basicity/base strength distribution, and catalytic activity/selectivity, were influenced by the rare earth doping of SnO2 and also by the annealing temperatures. Doping led to chemical and micro-structural variations at the surface of the SnO2 particles. Changes in the catalytic properties of the samples, such as selectivity toward ethylene, may be ascribed to different dopings and annealing temperatures.

Doping saturation in dye-sensitized solar cells based on ZnO:Ga nanostructured photoanodes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Al3+ environments in nanostructured ZnAl2O4 and their effects on the luminescence properties

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A Joint Experimental and Theoretical Study on the Nanomorphology of CaWO4 Crystals

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Platinum-coated nanostructured oxides for active catalytic electrodes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Electronic structure, growth mechanism and photoluminescence of CaWO4 crystals

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of variations in annealing temperature and metallic cations on nanostructured molybdate thin films

Crystalline molybdate thin films were prepared by the complex polymerization method. The AMoO(4) (A = Ca, Sr, Ba) films were deposited onto Si wafers by the spinning technique. The Mo-O bond in the AMoO(4) structure was confirmed by FTIR spectra. X-ray diffraction revealed the presence of crystalline scheelite-type phase. The mass, size, and basicity of A(2+) cations was found to be dependent on the intrinsic characteristics of the materials. The grain size increased in the following order: CaMoO4 < SrMoO4 < BaMoO4. The emission band wavelength was detected at around 576 nm. Our findings suggest that the material's morphology and photoluminescence were both affected by the variations in cations (Ca, Sr, or Ba) and in the thermal treatment.

Thermal evaporation furnace with improved configuration for growing nanostructured inorganic materials

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Synthesis and characterization of mesoporous TiO2 nanostructured films prepared by a modified sol-gel method for application in dye solar cells

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fabrication of coaxial TiO2/Sb2S3 nanowire hybrids for efficient nanostructured organic- inorganic thin film photovoltaics

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

NIR luminescent Er3+/Yb3+ co-doped SiO2-ZrO2 nanostructured planar and channel waveguides: Optical and structural properties

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

O papel dos modificadores de rede na produção da fotoluminescência no CaWO4

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)