Artificial antibodies for troponin T by its imprinting on the surface of multiwalled carbon nanotubes: Its use as sensory surfaces

A novel artificial antibody for troponin T (TnT) was synthesized by molecular imprint (MI) on the surface of multiwalled carbon nanotubes (MWCNT). This was done by attaching TnT to the MWCNT surface, and filling the vacant spaces by polymerizing under mild conditions acrylamide (monomer) in N,N′-methylenebisacrylamide (cross-linker) and ammonium persulphate (initiator). After removing the template, the obtained biomaterial was able to rebind TnT and discriminate it among other interfering species. Stereochemical recognition of TnT was confirmed by the non-rebinding ability displayed by non-imprinted (NI) materials, obtained by imprinting without a template. SEM and FTIR analysis confirmed the surface modification of the MWCNT. The ability of this biomaterial to rebind TnT was confirmed by including it as electroactive compound in a PVC/plasticizer mixture coating a wire of silver, gold or titanium. Anionic slopes of 50 mV decade−1 were obtained for the gold wire coated with MI-based membranes dipped in HEPES buffer of pH 7. The limit of detection was 0.16 μg mL−1. Neither the NI-MWCNT nor the MWCNT showed the ability to recognize the template. Good selectivity was observed against creatinine, sucrose, fructose, myoglobin, sodium glutamate, thiamine and urea. The sensor was tested successfully on serum samples. It is expected that this work opens new horizons on the design of new artificial antibodies for complex protein structures

Prognostic value of the percentage of positive fragments in biopsies from patients with localized prostate cancer

OBJECTIVE: To assess the prognostic value of the percentage of positive fragments (PPF) in biopsies from patients with localized prostate cancer (PCa) undergoing radical prostatectomy. MATERIALS AND METHODS: During the period from March 1991 to November 2000, 440 patients were selected. Cases receiving neoadjuvant or adjuvant hormone therapy, or adjuvant radiotherapy, were excluded, as were cases presenting Gleason scores higher than 6 at biopsy. PPF was defined as the total number of fragments divided by the total number of biopsy fragments times 100. This variable was initially divided into categories from 0 to 25%, 25.1% to 50%, 50.1 to 75% and 75% to 100%. During the postoperative period, patients were assessed every 2 months for 1 year, then every 6 months for 5 years, and then yearly. Biochemical recurrence was defined as serum PSA higher than or equal to 0.4 ng/mL. Median follow-up was 60 months. RESULTS: One hundred and nine (24.8%) of the 440 patients under study had biochemical recurrence. In the univariate analysis, PPF significantly influenced disease-free survival (log-rank, p < 0.001), and patients with PPF between 75 and 100% presented a risk of a biochemical recurrence of the disease 3 times higher than patients with PPF between 0 and 25% (p < 0.001). After the Cox regression analysis, both serum PSA (p = 0.001) and PPF (p < 0.001) showed to be independent predictive factors for disease-free survival following surgery. CONCLUSION: PPF measurement in biopsy is a simple and practical method, which should be routinely used as a predictive factor for biochemical recurrence in patients with PCa presenting Gleason scores between 2 and 6.Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina (EPM) Division of UrologyUNIFESP, EPM, Division of UrologySciEL

Effects of the consumption of polyunsaturated fatty acids on the oxidative status of adult dogs

The present study evaluated the alterations of the oxidative stress markers in adult dogs fed with high levels of PUFA from the mixture of soybean oil enriched with docosahexaenoic acid (DHA) and supplemented with a natural algae-based antioxidant (AOX). Twelve healthy adult (2 years old) Beagle dogs (6 males and 6 females, 11.20 ± 1.92 kg BW), were distributed in 2 completely randomized blocks design and fed with 4 experimental diets coated with 2 lipid sources: saturated (13% bovine tallow) or unsaturated (13% soybean oil enriched with DHA), supplemented or not with 500 mg of AOX for 4 wk, intercalated with a 4 wk adaptation period. Blood samples were collected on days 0, 15, and 30 of each block. Glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), sulfhydryl group (SH), protein carbonylation, thiobarbituric acid reactive substances (TBARS), and total reactive antioxidant potential (TRAP) were evaluated in the serum, while GSH-Px, SOD, glutathione S-transferase (GST), catalase (CAT), SH, and TBARS were measured in erythrocytes. There was no significant difference in most of the oxidative markers evaluated. In contrast, GST activity in erythrocytes was greater in the animals that consumed the diets coated with bovine tallow compared to dogs that consumed diets coated with soybean oil enriched with DHA (P < 0.05). Serum from dogs fed on diets supplemented with AOX presented greater TRAP values (P < 0.05). These data demonstrate that the concentrations of unsaturated fatty acids used in the diets for dogs were not sufficient to cause large changes in the oxidative status. It was not possible to evaluate the efficiency of the natural antioxidant in maintaining the oxidative balance of the animals as it appears that the oxidative status of the dogs was not challenged by the unsaturated diets. Our findings also suggest that dogs, as descendants from carrion carnivores, may have some natural protection against oxidatio

NIR micro beam-splitter by saw-dicing of glass substrate for Optical Coherence Tomography

This paper reports the fabrication of a near infrared (NIR) micro beam-splitter (MBS) for Optical Coherence Tomography (OCT) applications. The proposed configuration is based on saw-dicing micromachining of glass substrate combined with thin film deposition of a dielectric multilayer. In order to obtain a splitting with horizontal and vertical transmitted/reflected beams, a 45° surface was fabricated with conventional dicing blades. A dielectric multilayer based only in four thin films was optimized for NIR range (800-900 nm) and for a 50/50 non-polarized split ratio. This multilayer is deposited in the 45° micro machined surface. The MBS offers the possibility of wafer-level alignment and assembly, representing the first step towards OCT miniaturization.- (undefined

Phenolic profile by HPLC-MS, biological potential, and nutritional value of a promising food: Monofloral bee pollen

The objective of this study was to determine physicochemical and phenolic profiles as well the antioxidant and antimicrobial capacities of monofloral bee pollen samples from Brazil. Traditional methods were used. The phenolic profile was determined by high-performance liquid chromatography-mass spectrometry (HPLC-MS). The protein (10.6–33.9 g/100g), lipids (3.2–8.3 g/ 100g), ashes (2.6–3.8 g/100g), total phenolic (5.6–29.7 mg GAE/g), and total flavonoid (0.3– 19.0 mg QE/g) values were variable, even between products with the same botanical origin. The minerals analyzed were found in amounts varying between 10 mg/kg and 9.1 g/kg. Each product presented specific color parameters. Myrcia bee pollen presented the greater antioxidant capacity, and Mimosa scabrella bee pollen from Santa Catarina state was the most efficient in inhibiting bacteria and yeasts. Among the compounds identified by HPLC-MS, flavonoid 3-O-glycosides predominated. The physicochemical and phenolic profiles of each sample were distinct, and there was no pattern between monofloral products of the same pollen type.The authors are grateful to beekeepers who provided samples. MM Moreira is also grateful to FCT/MEC and FEDER, under the Partnership Agreement PT2020 through the project UID/QUI/50006/2013 - POCI/01/0145/FERDER/007265.info:eu-repo/semantics/publishedVersio

Metodologia para identificação do componente fundamental da tensão da rede baseada no algoritmo recursivo da TDF

Considering the increasing demand on digital processing techniques for power electronics and power systems application, this paper deals with the use of a Recursive Discrete Fourier Transform (RDFT) for phase angle, frequency and magnitude identification of the grid fundamental voltages, irrespective to waveform distortions, frequency or amplitude deviations. It will be discussed that if the fundamental frequency of the measured voltages exactly matches the frequency for which the DFT has been designed, an ordinary RDFT algorithm is completely able to provide the necessary information about phase, frequency and magnitude. Two additional algorithms have been proposed to ensure the correct performance if the frequency departs from its nominal value: one for phase correction and another for identification of the fundamental component magnitude. Moreover, it is important to point out that by means of the proposed algorithms, the fundamental component can be identified in less than 2 cicles, independently of the input voltage signal. The analysis of the RDFT has been performed by means of simulation results. In order to evaluate the behavior of the RDFT in a practical system, experimental results regarding to the synchronization of a small generator and the power grid will be presented.Considerando a crescente utilização de técnicas de processamento digital de sinais em aplicações de sistemas eletrônicos e ou de potência, este artigo discute o uso da Transformada Discreta de Fourier Recursiva (TDFR) para identificação do ângulo de fase, da freqüência e da amplitude das tensões fundamentais da rede, independente de distorções na forma de onda ou de transitórios na amplitude. Será discutido que, se a freqüência fundamental das tensões medidas coincide com a freqüência a qual a TDF foi projetada, um simples algoritmo TDFR é completamente capaz de fornecer as informações requeridas de fase, freqüência e amplitude. Dois algoritmos adicionais são propostos para garantir seu desempenho correto quando a freqüência difere do seu valor nominal: um deles para a correção do erro de fase do sinal de saída e outro para identificação da amplitude do componente fundamental. Além disto, destaca-se que através dos algoritmos propostos, independentemente do sinal de entrada, a identificação do componente fundamental pode ser realizada em, no máximo, 2 ciclos da rede. Uma análise dos resultados evidenciados pela TDFR foi desenvolvida através de simulações computacionais. Também serão apresentados resultados experimentais referentes ao sincronismo de um gerador síncrono com a rede elétrica, através dos sinais fornecidos pela TDFR.38139

Riscos coletivos e impacto do uso de agrotóxicos sobre a saúde humana e ambiental: um estudo piloto de saúde ocupacional

Este artigo mostra os resultados obtidos em um projeto de avaliação do impacto do uso de agrotóxicos sobre uma comunidade agrícola do cstado do Rio dc Janciro ativamcntc cnvolvida com o uso dc pcsticidas. A abordagem utilizada foi de avaliaçào de riscos ocupacionais e coletivos. já que além do grupo de trabalhadores ocupacionalmente cxpostos aos agrotóxicos. também foi avaliado um grupo de crianças ejovens da comunidade. alguns dos quais também trabalhadores rurais. Os resultados obtidos demonstram claramente que ocorre superexposição aos pesticidas utilizados. evidenciando agravos nào só à saúde das populações expostas. mas também ao meio ambiente

Unveiling the efficiency of microwave-assisted hydrothermal treatment for the preparation of SrTiO3 mesocrystals

Material processing has become essential for the proper control, tuning and consequent application of the properties of micro/nanoparticles. In this case, we report herein the capability of the microwaveassisted hydrothermal (MAH) method to prepare the SrTiO3 compound, as a case study of inorganic compounds. Analyses conducted by X-ray diffraction, X-ray photoelectron and X-ray absorption spectroscopies confirmed that the MAH route enables the formation of pristine SrTiO3. The results indicated that the combination of thermal and non-thermal effects during the MAH treatment provides ideal conditions for an efficient and rapid synthesis of pristine SrTiO3 mesocrystals. Scanning electron microscopy images revealed a cube-like morphology (of ca. 1 mm) formed via a self-assembly process, influenced by the MAH time. Additionally, photoluminescence measurements revealed a broad blue emission related to intrinsic defects, which decreased with the MAH synthesis time