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Global approaches for ecological restoration in urban environments
2025 - BERTOLETI, ISABELLA A. F.; FERREIRA, MAURICIO L.; GOMES, EDUARDO P. C.; RODRIGUES, ELAINE A.; NIEVOLA, CATARINA C.
Since the Industrial Revolution, global urbanization has expanded rapidly, leading to serious implications for human well-being and biodiversity. The rapid construction of cities has resulted in significant habitat loss, especially in the context of anticipated climate changes. Identifying trends in forest restoration in urban areas can contribute to implementing adaptive and mitigating measures that support future public policies. Using the PRISMA method, this study aimed to identify scientific articles describing restoration approaches in urban forests, focusing on trends that facilitate model development in urban regions facing rising temperatures and droughts. Our results show that, despite convergence favoring ecological restoration in urban areas, the scientific knowledge supporting model development is still in progress. Most reviewed articles focused on countries with temperate forests, while none addressed the tropics. Our results highlight that restoration requires a strategic approach, prioritizing native species and combining local knowledge with scientific expertise. Community involvement and continuous monitoring are crucial to maintaining ecological functions and adapting to rapid climate-related changes occurring globally, especially in the tropical zone. We also emphasize that forest restoration strategies in cities should be incorporated into long-term urban policies and not remain solely within the scope of compensatory actions. This work highlights a gap in forest restoration in urban areas and highlights the importance of countries in tropical regions developing more research with these approaches.
Feasibility study of the use of a silicon photomultiplier coupled to a scintillator for kVp measurement based on spectrometry
2025 - SILVA, JONATHAN R. da; MURATA, HELIO M.; SANTOS, LEONARDO C. dos; ALCANTARA NUNEZ, JUAN A.; CARVALHO, DIEGO V. de S.; SANTOS, ADELSON D. dos; BANOS RODRIGUEZ, UBALDO; POTIENS, MARIA da P. A.; BONIFACIO, DANIEL A. B.
This study proposes a spectroscopic and non-invasive approach to measure the kVp of an X-ray tube using a silicon photomultiplier (SiPM) coupled to a GaGG scintillator crystal. Several experimental setups were explored to assess the feasibility and performance in measuring the kVp based on international standards IEC 61267:2005 and IEC 61676:2002. The energy spectrum was obtained through pulse height analysis. System calibration was performed using radioactive sources emitting characteristic X-rays and gamma radiation. Determination of the maximum energy of the X-ray spectrum was based on a linear regression aiming for a goodness of fit to reduce uncertainty in kVp. The approach was successfully evaluated for specific radiology beams, including mammography, with a maximum uncertainty of 6.5% in the kVp values for the tested beam qualities.
GMP compliant microbiological monitoring in hot cells for radiopharmaceuticals preparations
2025 - SANTOS, RODRIGO da S.; ZAPPAROLI, CARLOS L.; SANTOS, JOEL M. dos; CAETANO, GABRIELA F. da R.; CAVALCANTI, MARCELO de G. P.; ANDRADE, DELVONEI A.
Radiopharmaceuticals are produced inside specialized equipment named hot cell. The integration between cleanrooms and hot cells allows the radiopharmaceutical production to meet radiological protection and Good Manufacturing Practices (GMP) standards, as established by regulatory agencies. The installation of a hot cell in a pharmaceutical cleanroom is a complex activity that must be documented and validated through qualification protocols. This study aims to perform microbiological monitoring in a hot cell for aseptic radiopharmaceutical preparations at the IPEN radiopharmacy facilities, considering the active air, settle plates, contact plates, and indirect samples of gloves and clamps, as part of the equipment’s Operation Qualification (OQ) protocol. Microbiological monitoring was performed in five chambers of the hot cell (grade A and B). Four of the five chambers presented microbiological contamination within the limits established by the standard for all tests performed. The fifth chamber (Material Outlet) presented technical and construction limitations that prevented the active air sample test from being performed, so the hot cell partially met the regulatory requirements. Complementary tests, such as air cleaning by concentration of non-viable particles, detection of leaks in filtration systems, and air flow testing will contribute to justify the classification of the Material Outlet chamber.
Flowability of NbC-based cermets for additive manufacturing via L-PBF
2025 - CONDOTTA, RODRIGO; MIRANDA, FABIO; PEREIRA, NATHALIA M. G.; SANTOS, MARCELO O. dos; RODRIGUES, DANIEL; JANASI, SUZILENE R.; ORTEGA, FERNANDO S.; BATALHA, GILMAR F.
Niobium-based refractory alloys have attracted attention in several industrial areas, such as metalworking, steelmaking, military, and armoring applications, among others. The production of these refractory alloys using additive manufacturing techniques, specifically selective laser fusion in a powder bed (L-PBF), has been a major challenge; this is primarily due to the complex optimization of the sintering process parameters required to obtain dense parts, free of porosity or cracks, and to achieve highly homogeneous layers in the powder bed. However, the success of L-PBF is highly dependent on the physical properties of the powders used in the process. Key factors such as good flowability, reduced particle size and narrow distribution, sphericity, and density influence powder spreading, powder layer uniformity, and the final part integrity. Furthermore, properties of the composite, such as hardness, toughness, and wear resistance, can be modified by changing the cermet composition, which could also negatively impact its flowability. This work aims to evaluate the physical properties of NbC-based cermets with different compositions to better understand their influence on metallic powder flowability. Optimizing powder properties and flowability through processing parameters is crucial for L-PBF to fully harness the potential of NbC-based cermets, thereby paving the way for their broader adoption in high-performance applications.
Aplicação da irradiação por feixe de elétrons para remediação de compostos farmacêuticos na água
2025 - TOMINAGA, FLAVIO K.; SILVA, THALITA T.; LEO, PATRICIA; BORRELY, SUELI I.
Um número significativo de produtos farmacêuticos tem sido lançado no ambiente aquático. Esses compostos não são completamente removidos pelas estações de tratamento de água e esgoto. Além disso, esses contaminantes não são comumente monitorados e possuem potencial para causar efeitos adversos à saúde humana e ao meio ambiente. A irradiação por feixe de elétrons (EBI) tem sido aplicada como uma um método alternativo sustentável na gestão da água, sendo eficaz na remoção de poluentes orgânicos recalcitrantes em baixas doses. Este estudo tem como objetivo avaliar o efeito da EBI na toxicidade de quatro fármacos das classes anti-inflamatório (ácido acetilsalicílico), antidepressivo (fluoxetina), antibiótico (ciprofloxacina) e antidiabético (metformina), utilizando organismos de diferentes níveis tróficos (Daphnia similis, Vibrio fischeri e Saccharomyces cerevisiae). O espectro UV-Vis mostrou alterações em todos os perfis de curvas para os fármacos após irradiação com 2,5 kGy. Os resultados de toxicidade indicaram que os efeitos variaram conforme o organismo e o fármaco estudado. Para o ácido acetilsalicílico, foi observado aumento da toxicidade para os três organismos. Em contraste, para a fluoxetina, foi alcançada uma redução significativa da toxicidade (60%) para D. similis, enquanto não foram notadas alterações de toxicidade para a bactéria e a levedura. Em relação à metformina, os subprodutos radiolíticos foram tóxicos apenas para o microcrustáceo, possivelmente devido à presença residual de peróxido de hidrogênio. Por fim, para a ciprofloxacina, verificou-se um aumento da toxicidade em D. similis e V. fischeri, enquanto foi observada a detoxificação em S. cerevisiae. Em conclusão, este estudo demonstrou que a EBI é eficaz na remoção de fármacos e destacou a importância da utilização de diferentes organismos para uma avaliação de toxicidade mais abrangente.
Stability improvement of irradiated polymer composites by inorganic compounds
2025 - ZAHARESCU, TRAIAN; LUGAO, ADEMAR B.
The long-term usage of polymer products necessitates addressing the appropriate preservation of their low oxidation state that extends the warranty period. The addition of pertinent stabilization components into the composite formulations (synthesis and natural antioxidants, pristine and doped oxides, clays or couples of them) produces an improvement in the kinetic parameters characterizing the accelerated degradation that occurs during high-energy exposures. The competition between the material ageing and the mitigation of oxidation is controlled by the protection efficiency. In this paper, the main advantages of inorganic structures in comparison to classical organic antioxidants are emphasized. A significant improvement in stability, simultaneously associated with the enhancing of functional characteristics, the lack of migration, low cost and easy accessibility, make the reevaluation of certain fillers as stabilizers appropriate. The correlation between the functional properties and the filler nature in polymer materials may be reconsidered for the assessment of the participation capability of inorganic structures in the inhibition of oxidation by the inactivation of free radicals. The lifetimes of degradation intermediates extended by the activities of inorganic compounds are increased by means of electrical interactions involving the unpaired electrons of molecular fragments. These physical contributions are reflected in chemical stability. An essential feature for the presented inorganic options is a strong impact on the recycling technologies of polymers by radiation processing. Plastic products, including all categories of macromolecular materials, can gain an increased durability through the inorganic alternative of protection.
Diamond-like carbon in ventricular assist devices
2025 - SA, ROSA C. L. de; LEAO, TARCISIO F.; SILVA, EVANDRO D. da; LOPES JUNIOR, GUILHERME B.; NISHIDA, BRENO; SOUSA SOBRINHO, JOSE R. C. de; RAMIREZ-RAMOS, MARCO A.; MORO, JOAO R.; CORAT, EVALDO J.; TRAVA-AIROLDI, VLADIMIR J.; BOCK, EDUARDO G. P.
Diamond-like carbon (DLC) coatings have become a prominent strategy to enhance the performance and hemocompatibility of ventricular assist devices (VADs). This review presents a comprehensive overview of the historical development of DLC coatings for VADs, the main DLC deposition techniques, types of blood pumps, substrate materials, and specific applications in VADs. DLC coatings, deposited via methods such as plasma-enhanced chemical vapor deposition, offer high hardness, chemical inertness, excellent wear resistance, and hemocompatibility, making them suitable for blood-contacting components in continuous-flow centrifugal pumps and continuous axial-flow pumps. The ability to apply DLC to various substrates, including metals and polymers, further broadens its biomedical utility. Comparative analysis with other hemocompatible coatings, such as heparin, titanium nitride, and 2-methacryloyloxyethyl phosphorylcholine polymers, demonstrates that DLC provides a unique balance of durability and blood compatibility, although challenges remain regarding long-term adhesion and stability. Advances in doped and nanostructured DLC films continue to improve antimicrobial and antithrombotic properties. Overall, DLC coatings represent a significant advancement in the quest for safer, longer-lasting VADs, but further research is needed to optimize their clinical performance and address remaining limitations.
Enhanced ethanol reforming with catalytic active ruthenium species derived from solid solution in lanthanum chromite
2025 - MORAES, TAMARA S.; FERLAUTO, ANDRE S.; TINTI, VICTOR B.; FLORIO, DANIEL Z. de; PIAZZOLLA, FERNANDO; MIURA, YOHEI; DEAN, DAVID P.; PHAM, HIEN N.; MILLER, JEFFREY T.; DATYE, ABHAYA K.; FONSECA, FABIO C.
Ethanol steam reforming (ESR) is a promising route for renewable hydrogen production, but it requires highly active and coke-resistant catalysts to efficiently convert ethanol into hydrogen-rich mixtures. The ESR catalytic activity is investigated in single-phase LaCr1−xRuxO3 solid solutions with 0.0 ≤ x ≤ 0.20. Highly active ruthenium species are formed at the surface of the oxide in operando during ESR at 600 °C. These species have remarkable stability for ESR with strong resistance to coke formation, resembling single-atom catalysts. Samples reduced ex situ at higher temperature (900 °C) exhibit Ru exsolved nanoparticles with lower catalytic stability than the species obtained in operando during the ESR reaction. X-ray absorption spectroscopy and high-resolution transmission electron microscopy reveal that small metallic Ru species (≤ 2 nm) are formed under ESR reaction conditions, whereas in samples exsolved at 900 °C such species coexist with larger exsolved Ru particles (~5 nm), which are more likely to deactivate. The experimental results provide an innovative approach for solid solution-derived species in a refractory oxide matrix that are valuable for designing robust catalysts for ESR.
Surfactant-free polyol synthesis of effective Pd-Cu nanomaterials for H2/O2 solid polymer electrolyte fuel cells
2025 - ISIDORO, ROBERTA A.; KOKOH, KOUAKOU B.; SAHIN, NIHAT E.; FONSECA, FABIO C.; NAPPORN, TEKO W.; SANTIAGO, ELISABETE I.
This study presents a facile synthesis of carbon-supported binary palladium-copper (Pd-Cu/C) nanomaterials designed to achieve competitive catalytic activity while reducing material costs in solid polymer electrolyte (SPE) fuel cells. A surfactant-free, microwave-heated polyol process is employed to synthesize Pd/C and Pd-Cu/C nanomaterials with mean particle size below 4.0 nm. The electrocatalytic activity toward the oxygen reduction reaction (ORR) and the corresponding kinetic parameters of Pd-Cu/C electrodes with varying compositions are systematically interrogated using rotating disk electrode (RDE) measurements. Notably, Tafel analysis reveals a slope of 60 ± 2 mV per decade at low current densities, indicating that the first electron transfer to molecular oxygen (O2) is the rate-determining step. At higher current densities, a slope of 144 ± 8 mV per decade suggests a transition to proton-coupled electron transfer as the dominant mechanism. Furthermore, electrochemical performance of membrane-electrode assemblies (MEAs) reveals a peak power density of 475 mW cm−2 with a Pd/C cathode under optimal operating conditions. However, increasing the Cu content in the Pd-Cu/C catalysts results in a marked decrease in current density, likely due to partial Cu dissolution. These findings highlight the potential of binary Pd-Cu nanomaterials as promising alternatives to platinum-based catalysts for Pt-free SPE fuel cell applications.
Physical characterization of composites based on yttria-stabilized zirconia and doped lanthanum gallate
2025 - FUJIMOTO, TALITA G.; SERIACOPI, V.; MACHADO, IZABEL F.; MUCCILLO, REGINALDO; MUCCILLO, ELIANA N. S.
This work reports a systematic study on the microstructure, electrical conductivity, and nanoindentation of 8 mol% yttria-stabilized zirconia (8YSZ) and La0.9Sr0.1Ga0.8Mg0.2O3-δ (LSGM), in both pure form and as composites. The main purpose was to evaluate the effects of the minor phase on the properties of the composite materials. Commercial 8YSZ was the major phase. Pure LSGM and composites consisting of 1, 10, and 20 wt.% LSGM were prepared by the solid-state reaction method. Sintering experiments were carried out from 1200°C to 1450°C. The temperature of maximum shrinkage decreased with increasing LSGM content. The average grain size of the composites was dependent on the relative proportion of the minor phase. Interface reactions occurred during sintering. Electrical conductivity of the composites was found to be lower compared to that of 8YSZ. The hardness showed no significant variation with the minor phase content, although a beneficial effect on the elastic modulus was noted for composites containing 10 wt.% LSGM.
Forensic determination of adhesive vinyl microplastics in urban soils
2025 - SEBASTIAO, G. I. A.; RANI-BORGES, B.; DIPOLD, J.; FREITAS, A. Z.; WETTER, N. U.; ANDO, R. A.; WALDMAN, W. R.
Plastic production and consumption hubs are mainly concentrated in urban centers, causing the soil in these places to become sinks of plastic fragments. Adhesive vinyl polymers are widely used in various commercial sectors and, to the best of our knowledge, this is the first study to investigate the potential for this type of material to form microplastics in urban soils. This proof-of-concept work started by studying the soil around a sign made of adhesive vinyl that had been exposed to the weather for eight years and showed evident signs of degradation, like cracking and color fading. We separated the microplastics with a two-step density separation protocol and selected only the microplastics targeted by this research, finding up to 5,570 fragments produced from 1 cm2 of adhesive vinyl film. In the soil below the sign, we registered 5.6 × 10^4 fragments kg^-1 of dry soil on its topsoil layer (0–10 cm), 1.2 × 10^4 fragments kg^-1 in the 10–20 cm layer, and 1 × 10^4 fragments kg^-1 in the 20–30 cm layer. At a distance of 1 and 2 m from the sign, the highest concentration of fragments was also in the topsoil, respectively 9.3 × 10^3 and 5.3 × 10^2 fragments kg^-1. We also observed that vertical and horizontal transport was not favored, causing the formation of hotspots near the source and that the area of the fragments did not influence vertical transport. Another important finding regarding the characterization technique is that degraded polyvinyl chloride is unlikely to be identified through FTIR without comparison to the source. Here, we presented a low-cost forensic assessment of the association between the presence of MPs and its source that can be used both for the development of public policies and for setting up quality controls for polluting companies. The results here presented reveal the need to rethink the use and types of materials used for visual identities and signage in urban environments.
The EDXRF analysis to monitor iron deficiency anemia
2024 - GOES, M. P. O.; ZAMBONI, C. B.; BENEDITO, M. G. M.; AZEVEDO, M. R. A.
Iron Deficiency Anemia is a significant global issue, particularly affecting pregnant women and young children. Traditional methods of diagnosing iron-deficiency anemia generally require extensive and costly laboratory procedures. This study explores the feasibility of using portable Energy Dispersive X-ray Fluorescence (EDXRF) technology for assessing iron concentration in whole blood samples from donors diagnosed with iron deficiency anemia. The results indicated a marked decrease in iron levels in the blood samples from patients with anemia compared to the control group. The EDXRF technique demonstrated several advantages, including simplicity in sample collection, rapid measurement time, and low cost. This method is particularly promising for use in situations where biological material is limited, such as in pediatric practices for newborns. The study concludes that portable EDXRF technology is an effective and efficient tool for diagnosing iron deficiency anemia, potentially improving diagnostic accessibility and outcomes.
Development of spheroid in co-culture of prostate tumor with human fibroblast, using the hanging drop technique with plate inversion for analysis of GammaCell220 irradiation in Co-60
2026 - MONTEIRO, T.; RODRIGUES, A. A.; SILVA, G. D.; SANTOS, E. C.; FALCAO, P. L.; PRUDENTE, S. R.; PAZ, M. M.; VIEIRA, D. D.
The development of tumor spheroids in co-culture with human fibroblasts represents an innovative approach to modeling the prostate cancer microenvironment and assessing radiation effects. In this study, we employed the "hanging drop" technique in conjunction with plate inversion to generate three-dimensional spheroids composed of prostate tumor cells (LNCAP cell line) co-cultivated with human fibroblasts. This approach aims to create a more representative in vivo-like tumor environment, facilitating a detailed analysis of the interactions between tumor cells and fibroblasts in 3D conditions. The formed spheroids were exposed to gamma radiation using a GammaCell 220 irradiator with Co-60, with the goal of investigating the effects of radiation on both fibroblastic and tumor cells. Gamma radiation is known to induce cell death, and this study examines how such damage impacts cellular morphology within the spheroid microenvironment.
Determination of the total retention capacity of 99Mo in anionic extracting agent
2024 - YAMAZAKI, I. M.; MOREIRA, D. S.; DIAS, M. S.; SENEDA, J. A.; KOSKINAS, M. F.
The Nuclear Metrology Laboratory (LMN) at IPEN-CNEN/SP is developing a research project aimed at studying analytical techniques for determining radioactive impurities emitting alpha and beta particles. This project started with the determination of impurities present in ^99Mo, which is used to obtain the radiopharmaceutical ^99mTc by means of radiochemical separation in the ^99Mo/^99mTc generator. The study of the anionic extracting agent Strata X-A, widely used in quality analysis, was carried out by means of a breakthrough curve in order to validate its total exchange capacity for Mo. The breaking point was determined at (2.75 +/- 0.14) mL, showing that just one 0.5 g Strata X-A cartridge is sufficient to retain 1.0 mL of a (Na2MoO4 + ^99Mo) solution at a concentration of 2.42 g L^-1.
Evaluation of the combination of linear alkylbenzene sulfonate (LAS) with emerging pollutants
2024 - GARCIA, V. S. G.; TOMINAGA, F. K.; BOIANI, N. F.; FEHER, A.; BORRELY, S. I.
The presence of surfactants and other emerging pollutants in water bodies has become a major environmental concern in several places around the world, since these pollutants cause adverse problems in aquatic ecosystems and compromise public health regarding the supply of good quality water. These pollutants often originate from various sources, including industrial activities, pharmaceuticals, and personal care products. A critical aspect of this issue is that many of these pollutants and their mixtures are difficult to degrade in biological treatment processes, requiring auxiliary treatments. Electron beam technology has been applied in various environmental matrices to degrade these pollutants, helping not only to increase degradability, but also to reduce the toxicity of these compounds. The present work aimed to evaluate the single and combined effects of the LAS surfactant with emerging pollutants (caffeine and the antibiotic ciprofloxacin) on the aquatic organism Daphnia similis. The electron beam (EB) treatment for reducing the toxicity of isolated compounds was also evaluated. The organisms were exposed to samples (non-irradiated and irradiated LAS and mixtures) for 48 hours, and the observed effect was immobility. Toxicity was evaluated through EC50 (median effective concentration) calculations. The EC50 values showed a high toxicity level for the LAS surfactant, with EC50s below 9%. Caffeine and ciprofloxacin EC50 data were higher than 20%. The EC50% values of the mixtures were close to the values of the isolated compounds. After EB treatment (5 kGy), about 70% acute toxicity reduction was obtained for the LAS surfactant. The combined presence of surfactants and emerging pollutants in aquatic matrices requires a comprehensive approach to monitoring and mitigating their impacts in order to protect aquatic ecosystems and human health.
Protocol for handling contaminated maritime cargo returned to the country
2024 - ALMEIDA, M. C.; PERROTTA, P. R.; SANTOS, R.; ANDRADE, D. A.; WASSERMAN, M. A. V.
Responding to nuclear and radiological incidents is part of the responsibilities of the agency whose mission is nuclear and radiological safety; in the Brazilian case, the National Nuclear Energy Commission (CNEN), an autonomous structure of the Ministry of Science, Technology and Innovation (MCTI), Brazil. In 2022, the Nuclear and Radiological Emergency Response System (SAER) was activated to respond to a finding in a maritime container. The cargo, returned from abroad from a transshipment port due to the detection of an internal radioactive source, arrived in the country at the Port of Suape, in Pernambuco. It was then analyzed by the CNEN technical team, following regulatory norms and protocols. After work to remove the containerized packed material — metal scrap — the radioactive source was located and identified during the operation carried out in Caruaru-PE, headquarters of the metal scrap holding company. Immediately, the source was collected by the Regional Center for Nuclear Sciences - Northeast (CRCN-NE), in compliance with the country's safety regulations. Qualified and well-trained teams resulted in reliability of the process.
Research collaboration dynamics at the National Nuclear Energy Commission (CNEN)
2024 - JORDAO, A. A.; ARTHUR, V.
The growing recognition of university-industry collaborations as a strategic alternative for economic and social development at regional and national levels has fostered a continuous academic and political debate. Moreover, university-industry collaboration emerges as a strategic pathway for research production, particularly in developing and emerging countries. However, there is a scarcity of studies on university-industry collaboration oriented toward research production, as well as on its respective impacts, especially economic and social ones. To help fill this gap, this research examined the dynamics of research collaboration at the National Nuclear Energy Commission (CNEN), as well as its respective scientific, economic, and social impacts over the past three decades — the longest available data series, which adds originality and novelty to the research. Based on a descriptive and evaluative informetric analysis of internationally indexed publications in the Scopus (Elsevier) database, accessed through the SciVal platform, it was found that publications co-authored by CNEN with industry, government, and international actors, although less frequent, achieved greater resonance and influence in international knowledge networks, attracted more attention and interest from the international community, significantly exceeded the average expectation for similar publications, and exerted a more significant influence on patentable technologies and public policy formulation. These results may be useful for informing policies and guiding pathways to increase the prolificacy and impact of research.
Sustainable synthesis of cobalt nanoparticles for supercapacitor application
2024 - DUARTE, M.; FOO, C. T.; GONCALVES, K. O.; SILVA, D. V.; FARIA JR, R. N.; SAKATA, S. K.
The growing demand for renewable energy sources and the continuous increase in global energy demand are responsible for the need to develop new forms of energy storage. In this context, supercapacitors emerged due to properties such as high charge density, long durability, and reduced environmental impact. This work aims to develop electrodes based on cobalt oxide synthesized by ionizing radiation for use in supercapacitors. Synthesis by ionizing radiation consists of a sustainable and ecological approach to the production of nanoparticles, reducing the need for toxic reagents and high temperatures. Cobalt oxide nanoparticles were synthesized by irradiating a solution of cobalt acetate, followed by vacuum filtration and drying. The electrochemical properties of the material were evaluated using cyclic voltammetry in 1 M KOH. The results indicated that the cobalt oxide electrodes have a significant energy storage capacity, indicating their potential for use in supercapacitors.
Radiolabeling of porcine, murine growth hormone and a potential antagonist G118R-mGH for biodistribution study
2024 - NUNES, A. P.; MENEZES, F.; ALMEIDA, L. A.; POMIN, S. A.; FALCAO, P. L.; SOARES, C. R. J.
This study aimed to radiolabel porcine growth hormone (pGH), murine growth hormone (mGH), and its antagonist (G118R-mGH) with the iodine radioisotopes ¹³¹I and ¹²³I, to investigate the biodistribution and brain transport of these hormones. Radiolabeling was performed using the Chloramine T method, a protein iodination technique. The radiolabeled products were characterized by physicochemical techniques such as SDS-PAGE, size-exclusion high-performance liquid chromatography (HPLC-SE), and ascending paper chromatography, with measurements performed using single-photon emission computed tomography (SPECT). These measurements demonstrated high radiochemical purity, exceeding 95%, and preservation of molecular size. In vitro stability assays indicated that the radiotracers maintained their integrity for at least 24 hours. In vivo biodistribution studies in mice revealed distinct tissue distribution patterns for mGH and G118R-mGH, suggesting different uptake and metabolism mechanisms. The use of ¹²³I allowed for SPECT-CT imaging studies, which proved important for assessing the ability of mGH and G118R-mGH to cross the blood-brain barrier and distribute in specific regions of the brain. The results obtained in this work highlight the versatility of the radiolabeling protocol employed and its potential for investigating complex biological processes and application in research.
Effect of irradiation on residues from avocado oil processing
2024 - BARROS, J. P. A. A.; RONDAN-FLORES, L. M.; NEGRAO, B. G.; BARREIRA, D. A. S.; BENEDETTI, V. F.; SALIBA, A. S. M. C.; ALENCAR, S. M.; VILLAVICENCIO, A. L. C. H.
In the agro-industrial process, sustainability is an essential characteristic, and the reuse of waste plays an important role in this regard. However, in most cases, these materials are improperly discarded, leading to environmental, economic, and social implications. In this context, there arises a need to utilize waste by extracting nutritional substances that prevent food waste, developing by-products, and adding value to raw materials. It is worth noting that agro-industrial waste from the food industry contains significant amounts of nutrients and bioactive compounds, such as phenolics, antioxidants, carotenoids, fibers, vitamins, and minerals. For example, agro-industrial waste from avocado processing, such as the peel, seeds, and pulp after oil extraction, contains a large amount of bioactive compounds that may have some application. In view of this, the use of ionizing radiation can be considered an innovative technology that has been applied in various processes in the food industry, and it can be used to increase and/or preserve these compounds present in the waste. Thus, the objective of this study was to evaluate the effects of ionizing radiation on waste from avocado oil processing, such as the seed, peel, and extracted pulp. To achieve this objective, the samples were extracted through physical and chemical processes, obtaining a dry extract that was used for analyses of phenolic compound content and antioxidant activity. The results showed that doses of 5 kGy were sufficient to increase the amount of these compounds and antioxidant activity. The peel and seed, which contain the highest amount of compounds, were also the wastes that showed the greatest improvement with the irradiation process. At a dose of 10 kGy, the avocado peel showed significant improvement in both phenolic compound content and antioxidant activity. These results suggest that the use of ionizing radiation technology can be used in the reuse of agro-industrial waste. The results of this study indicated that ionizing radiation did not cause degradation of the compounds, providing strong evidence of one of the benefits of this technique, which is to preserve and maintain food quality.

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