Papers by Robson Bernardo
Journal of Engineering Research, Mar 28, 2023
Biphenyl polychlorinated (PCBs) belongs to a class of products persistent, bio accumulative and t... more Biphenyl polychlorinated (PCBs) belongs to a class of products persistent, bio accumulative and toxic synthetic organic chemicals. They are highly lipophilic pollutants and can accumulate in the food chain and adipose tissue. Although the use and production of PCBs have been severely banned in many countries, the legislation allows for the operation of equipment already installed, until it is fully replaced or replaced with a PCB-free product. The present study has the objective of verifying the presence of PCBs in the Bengalas River, in the Municipality of Nova Friburgo. Three collection points were analyzed monthly in the river from its source. The samples were collected monthly and lyophilized for a period of seven months. Subsequently, they were subjected to solid phase extraction (silica) with dichloromethane:hexane (1: 1: v/v) solvent. The samples were evaporated in a nitrogen atmosphere and analyzed by gas chromatography coupled to Mass Spectrometry (GC-MS), using tetrachloromethoxyylene as an internal standard. The analyses showed the presence of different types of PCBs and this result implies important deleterious effects on aquatic life as well as on those that use the waters of the river.
Objective: The main goal of this work was to evaluate the therapeutic potential of green SPIONs p... more Objective: The main goal of this work was to evaluate the therapeutic potential of green SPIONs produced with coconut water for treating cutaneous leishmaniasis caused by Leishmania amazonensis. Materials and methods: Optical and electron microscopy techniques were used to evaluate the effects on cell proliferation, infectivity percentage, and ultrastructure. Results: SPIONs were internalized by both parasite stages, randomly distributed by the cytosol located mainly in membrane-bound compartments. The selectivity index for intracellular amastigotes was higher than 240 times compared to current drugs used to treat the disease. Conclusion: The synthesized SPIONs showed an important and promising anti-Leishmania activity and can be considered a strong candidate for a new therapeutic approach for treating leishmaniases.
Journal of Engineering Research
All content in this magazine is licensed under a Creative Commons Attribution License. Attributio... more All content in this magazine is licensed under a Creative Commons Attribution License. Attribution-Non-Commercial-Non-Derivatives 4.0 International (CC BY-NC-ND 4.0).
Revista Cubana de Farmacia, 2016
Introduccion : el clorhidrato de merformina es un ingrediente farmaceuticamente activo utilizado ... more Introduccion : el clorhidrato de merformina es un ingrediente farmaceuticamente activo utilizado en el tratamiento de la Diabetes Mellitus tipo 2, el cual presenta una buena absorcion en el tracto gastrointestinal. En el mercado brasileno, se comercializan diversos medicamentos conteniendo este farmaco . Objetivo: estudiar el perfil de disolucion de dos medicamentos, para predecir su intercambiabilidad en condiciones " in vivo ". Metodos: las muestras (producto de referencia y similares) se analizaron a traves de su perfil de disolucion con las especificaciones de acuerdo con la Farmacopea Brasilena (5a ed). Las alicuotas de 10 mL se pipetearon durante un intervalo de tiempo de 5 a 45 minutos, en el cual fue determinado el porcentaje de farmaco disuelto. Resultados: el porcentaje de farmaco disuelto del producto de referencia en el ultimo momento fue 95,66 %, mientras que el farmaco similar solo demostro un 20,32 %. Tambien se analizo en un durometro manual la resistencia ...
Brazilian Journal of Health Review
A nanotecnologia é um dos campos da ciência que mais cresceu nos últimos anos com perspectivas de... more A nanotecnologia é um dos campos da ciência que mais cresceu nos últimos anos com perspectivas de revolucionar em várias áreas. Isto impulsiona cada vez mais a sua investigação e pesquisa em laboratórios e indústrias em todo o mundo. Como, por exemplo, a sua associação à área química. Neste âmbito, emerge a necessidade de serem realizadas reações nas quais utilizam-se elementos de baixo impacto ao meio ambiente, que alcancem alta eficiência e baixo custo, pois a atividade química está drasticamente relacionada à área ambiental, na criação de resíduos industriais que causam grande impacto ao meio ambiente. Com a perspectiva de minimizar estes desafios, o trabalho em questão, desenvolveu a síntese de nanoferritas de zinco utilizando produtos naturais, tal como o sumo do limão Taiti (Citrus latifolia). A presença do ácido cítrico tem como objetivo estabilizar as nanopartículas, que foram produzidas através do emprego do método Sol-Gel utilizando nitrato de ferro e zinco como precursore...
Acta Amazonica, 2020
This is the first study to investigate mercury (Hg) contamination in felid species in the Brazili... more This is the first study to investigate mercury (Hg) contamination in felid species in the Brazilian Amazon. We collected 26 fur samples from wild felids of four species (Puma concolor, Panthera onca, Leopardus pardalis and Leopardus wiedii) occurring in the Mamirauá and Amanã sustainable development reserves, in the state of Amazonas. Samples were from museum specimens, except for five P. onca samples collected from free-living individuals. Total Hg concentrations ranged from 0.12 to 48.1 µg g-1. Concentrations of Hg did not differ significantly between museum specimens and live individuals of P. onca, but varied significantly among species, with significantly higher concentrations for P. onca and L. pardalis, which could be related to factors such as diet and habitat.
Orbital: The Electronic Journal of Chemistry, 2018
In 2009, human hair samples were collected in Brazilian sites historically contaminated with orga... more In 2009, human hair samples were collected in Brazilian sites historically contaminated with organochlorine to assess the level of contamination with DDT and its metabolites in local human populations (Santos and São Vicente Estuary-São Paulo State). 122 hair samples from members of four contaminated community were collected (Pilões and Água Fria, Cubatão Center, Continental São Vicente and Guarujá), along with one noncontaminated sample (Bertioga). DDT and its metabolites were detected in approximately 70.0% of the hair samples from all areas, and its concentrations ranged from 50.3 ng.g-1 to 141.8 ng.g-1 in Cubatão Center and Pilões and Água Fria, respectively. The highest p,p'-DDT concentration was detected in Pilões and Água Fria (134 ng.g-1) and, Cubatão Center (43.9 ng.g-1) exhibited the lowest concentration. There was not a clear association between the occurrence of evaluated diseases and DDT detection in hair. None of the locally produced groceries appeared to be risk factors for the presence of DDT in hair. However, DDT concentrations found in this study showed an increase of DDT available for human exposure. These results strengthen the evidence of current exposure routes between DDT and the population of the estuarine region; therefore, this issue deserves further investigation.
Journal of Biochemistry, 2003
Sphingosine-1-phosphate (S1P) and phosphatidylinositol-4 phosphate [PtdIns(4)P] are important sec... more Sphingosine-1-phosphate (S1P) and phosphatidylinositol-4 phosphate [PtdIns(4)P] are important second messengers in various cellular processes. Here, we show that S1P and PtdIns(4)P are formed in purified basolateral membranes (BLM) derived from kidney proximal tubules, indicating the presence of a plasma membrane associated SPK (BLM-SPK) and phosphatidylinositol-4 kinase (PI-4K). We observed that S1P synthesis is linear with time, dependent on protein concentration, and saturable in the presence of increasing concentrations of sphingosine. Different from the observations on cytosolic SPKs, the formation of S1P by BLM-SPK is Mg(2+)-independent and insensitive to the classical inhibitor of the cytosolic SPKs, DL-threo-dihydrosphingosine. With sphingosine as substrate, the enzyme shows cooperative kinetics (n = 3.4) with a K(0.5) value of 0.12 mM, suggesting that BLM-SPK is different from the previously characterized cytosolic SPK. The formation of PtdIns(4)P markedly inhibits BLM-SPK activity. Conversely, a strong activation of PtdIns(4)P synthesis by the formation of S1P is observed. Taken together, these results indicate that (i) basolateral membranes from kidney cells harbor a SPK activity that potentially regulates renal epithelium function, and (ii) the formation of S1P mediated by SPK enhances PI-4K activity, while PtdIns(4)P in turn inhibits SPK, suggesting an interplay between these lipid signaling molecules. These findings suggest the possibility of crosstalk between sphingolipids and glycerolipids, which might be involved in the regulation of transepithelial fluxes across the BLM of kidney cells.
Nuclear migration is regulated by the LIS1 protein, which is the regulatory subunit of platelet a... more Nuclear migration is regulated by the LIS1 protein, which is the regulatory subunit of platelet activating factor (PAF) acetyl-hydrolase, an enzyme complex that inactivates the lipid mediator PAF. Among other functions, PAF modulates cell proliferation, but its effects upon mechanisms of the cell cycle are unknown. Here we show that PAF inhibited interkinetic nuclear migration (IKNM) in retinal proliferating progenitors. The lipid did not, however, affect the velocity of nuclear migration in cells that escaped IKNM blockade. The effect depended on the PAF receptor, Erk and p38 pathways and Chk1. PAF induced no cell death, nor a reduction in nucleotide incorporation, which rules out an intra-S checkpoint. Notwithstanding, the expected increase in cyclin B1 content during G2-phase was prevented in the proliferating cells. We conclude that PAF blocks interkinetic nuclear migration in retinal progenitor cells through an unusual arrest of the cell cycle at the transition from S to G2 pha...
Aim: The primary goal of this work was to synthesize low-cost superparamagnetic iron oxide nanopa... more Aim: The primary goal of this work was to synthesize low-cost superparamagnetic iron oxide nanoparticles (SPIONs) with the aid of coconut water and evaluate the ability of macrophages to internalize them. Our motivation was to determine potential therapeutic applications in drug-delivery systems associated with magnetic hyperthermia. Materials & methods: We used the following characterization techniques: X-ray and electron diffractions, electron microscopy, spectrometry and magnetometry. Results: The synthesized SPIONs, roughly 4 nm in diameter, were internalized by macrophages, likely via endocytic/phagocytic pathways. They were randomly distributed throughout the cytoplasm and mainly located in membrane-bound compartments. Conclusion: Nanoparticles presented an elevated intrinsic loss power value and were not cytotoxic to mammalian cells. Thus, we suggest that low-cost SPIONs have great therapeutic potential.
This is the first study to investigate mercury (Hg) contamination in felid species in the Brazili... more This is the first study to investigate mercury (Hg) contamination in felid species in the Brazilian Amazon. We collected 26 fur samples from wild felids of four species (Puma concolor, Panthera onca, Leopardus pardalis and Leopardus wiedii) occurring in the Mamirauá and Amanã sustainable development reserves, in the state of Amazonas. Samples were from museum specimens, except for five P. onca samples collected from free-living individuals. Total Hg concentrations ranged from 0.12 to 48.1 µg g-1. Concentrations of Hg did not differ significantly between museum specimens and live individuals of P. onca, but varied significantly among species, with significantly higher concentrations for P. onca and L. pardalis, which could be related to factors such as diet and habitat.
Nanomedicine, 2018
The primary goal of thiswork was to synthesize low-cost superparamagnetic iron oxide nanoparticle... more The primary goal of thiswork was to synthesize low-cost superparamagnetic iron oxide nanoparticles
(SPIONs) with the aid of coconut water and evaluate the ability of macrophages to internalize them. Our
motivation was to determine potential therapeutic applications in drug-delivery systems associated with
magnetic hyperthermia. Materials & methods: We used the following characterization techniques: X-ray
and electron diffractions, electron microscopy, spectrometry and magnetometry. Results: The synthesized
SPIONs, roughly 4 nm in diameter, were internalized by macrophages, likely via endocytic/phagocytic
pathways. They were randomly distributed throughout the cytoplasm and mainly located in membranebound
compartments. Conclusion: Nanoparticles presented an elevated intrinsic loss power value and
were not cytotoxic to mammalian cells. Thus, we suggest that low-cost SPIONs have great therapeutic
potential.
Journal of Environmental Science and Engineering B
The increasing use of pharmaceuticals throughout the world is generating a new environmental prob... more The increasing use of pharmaceuticals throughout the world is generating a new environmental problem where they are found in low concentrations, but the long-term risks to various organisms, as well as human health, are not yet known. These drugs, as well as their metabolites, are introduced into aquatic environments through excretions or discharges and may cause the same exposure as POPs (Persistent Organic Pollutants) due to its continued entry into the environment. The aim of this work is to develop a sensitive analytical method for the detection of ibuprofen and its metabolites in the Bengalas river that crosses the city of Nova Friburgo in the state of Rio de Janeiro. Three collection points were analyzed monthly in the river from its source, as well as points of treated water throughout the city. The samples were collected monthly and lyophilized. Subsequently, they were subjected to a solid phase extraction (silica) with the solvent dichloromethane: hexane (1:1; v/v). The samples were evaporated over a nitrogen atmosphere and subjected to a LC-MS (Liquid Chromatography with Mass Spectrometry) with 5% acetic acid gradient: acetonitrile as the mobile phase. In the search for drugs, there were found ions and fragments of ibuprofen (m/z 206, 205, 177) that were sought and compared to with their standard. These indicators can result in deleterious effects on aquatic life in these bodies of water, as well as on those who use this water from the Bengalas river.
ACTA AMAZONICA CITE AS: Lopes, M.C.B.; Carvalho, G.O.; Bernardo, R.R.; Macedo, J.; Lino, A.S.; Ra... more ACTA AMAZONICA CITE AS: Lopes, M.C.B.; Carvalho, G.O.; Bernardo, R.R.; Macedo, J.; Lino, A.S.; Ramalho, E.E.; Kasper, D.; Meire, R.O.; TORRES, J.P.M.; Malm, O. 2020. Total mercury in wild felids occurring in protected areas in the central Brazilian Amazon. ABSTRACT This is the first study to investigate mercury (Hg) contamination in felid species in the Brazilian Amazon. We collected 26 fur samples from wild felids of four species (Puma concolor, Panthera onca, Leopardus pardalis and Leopardus wiedii) occurring in the Mamirauá and Amanã sustainable development reserves, in the state of Amazonas. Samples were from museum specimens, except for five P. onca samples collected from free-living individuals. Total Hg concentrations ranged from 0.12 to 48.1 µg g-1. Concentrations of Hg did not differ significantly between museum specimens and live individuals of P. onca, but varied significantly among species, with significantly higher concentrations for P. onca and L. pardalis, which could...
In the present study, our main objective was to evaluate the biological activity and the kinetics... more In the present study, our main objective was to evaluate the biological activity and the kinetics of the humoral immune response in Swiss Webster mice using the biotherapic agent Trypanosoma cruzi 30DH.This compound was prepared following the pharmacotechnique described by Roberto Costa. Trypanosoma cruzi 30DH was evaluated by the parasitemia parameters and the humoral immune response, performed by Indirect Immunefluorescence Reaction (RIFI) to analyse IgM and IgG antibodies. Based on the biological activity, 50% of the animals in the group treated with the biotherapic agent survived. The group which received treatment and infection simutaneously and in the control group had 100% mortality. Higher IgG levels in the group of animals previously treated with the compound could be observed, presenting 1:80 and with sub-patent parasitemia. Our results suggest that the previous treatment with the biotherapic agent showed a humoral immune response, with higher serological titers and absenc...
Planta Med, 1999
A new steroidal saponin has been isolated from the rhizomes of Costus spicatus and its structure ... more A new steroidal saponin has been isolated from the rhizomes of Costus spicatus and its structure was elucidated as (3 beta, 22 alpha, 25R) -26-(beta-D-glucopyranosyloxy)-2-methoxyfurost-5-en-3-yl O-D-apio-beta-D-furanosyl-(1-->4)-O-[alpha-L-rhamnopyranosyl-(1--> 2)]- beta-D-glucopyranoside by means of IR, MS, NMR and chemical evidence.
Phytochemistry
A new rotenoid glycoside, clitoriacetal , was isolated from the roots of Clitoria fairchildiana. ... more A new rotenoid glycoside, clitoriacetal , was isolated from the roots of Clitoria fairchildiana. Its structure was established by spectroscopic and chemical methods.
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Papers by Robson Bernardo
(SPIONs) with the aid of coconut water and evaluate the ability of macrophages to internalize them. Our
motivation was to determine potential therapeutic applications in drug-delivery systems associated with
magnetic hyperthermia. Materials & methods: We used the following characterization techniques: X-ray
and electron diffractions, electron microscopy, spectrometry and magnetometry. Results: The synthesized
SPIONs, roughly 4 nm in diameter, were internalized by macrophages, likely via endocytic/phagocytic
pathways. They were randomly distributed throughout the cytoplasm and mainly located in membranebound
compartments. Conclusion: Nanoparticles presented an elevated intrinsic loss power value and
were not cytotoxic to mammalian cells. Thus, we suggest that low-cost SPIONs have great therapeutic
potential.
(SPIONs) with the aid of coconut water and evaluate the ability of macrophages to internalize them. Our
motivation was to determine potential therapeutic applications in drug-delivery systems associated with
magnetic hyperthermia. Materials & methods: We used the following characterization techniques: X-ray
and electron diffractions, electron microscopy, spectrometry and magnetometry. Results: The synthesized
SPIONs, roughly 4 nm in diameter, were internalized by macrophages, likely via endocytic/phagocytic
pathways. They were randomly distributed throughout the cytoplasm and mainly located in membranebound
compartments. Conclusion: Nanoparticles presented an elevated intrinsic loss power value and
were not cytotoxic to mammalian cells. Thus, we suggest that low-cost SPIONs have great therapeutic
potential.