Navegação Periódicos - Resumos por ano de publicação "2021"

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  • IPEN-DOC 28618

    DEL MASTRO, NELIDA L. ; GERVASONI, J.L.. Women in the nuclear field promoting Latin American integration. Biophysical Reviews, v. 13, n. 6, p. 1517-1517, 2021. DOI: 10.1007/s12551-021-00844-3

    Abstract: Nuclear energy is used for the generation of electricity, but also for the production of radioisotopes, desalination of sea water and also for the production of hydrogen. Activities in the nuclear field are in the area of science, technology and innovation that has long belonged to an essentially male domain, in which the contributions of women were neglected or underestimated. The central idea for the creation of Women in Nuclear, WiN Global, was to support and encourage women working in nuclear science and technology and encourage the promotion of understanding and knowledge of the benefits of the peaceful use of nuclear energy by the public. WiN Global currently has predominantly female members coming from 129 different countries, belonging to chapters or individually. Today, WiN Global is integrated by 53 WiN Global chapters. Forty-nine countries have their own chapters and there are also regional and international ones. The history of Latin American integration started during the political independence movement of the countries of the New Continent. Since then, up and downs were overcome in order to keep a regional ambiance of good relationship. In the present study, a new form of integration is presented by the efforts of the women working in the nuclear ambit. This important movement involves Latin American WiN chapters (such as WiN Argentina, WiN Brazil, WiN ARCAL) promoting activities for the integration of our region. In order to quantify, to some extent, the participation of Latin American women, this paper presents a survey crossing data of the number of related publications to help to address an objective analysis of the trend of this integration.

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  • IPEN-DOC 28619

    VIEIRA, DANIEL P. . Three-dimensional cellular culture system for testing of biological effects of radiations in tumoral and non-tumoral models. Biophysical Reviews, v. 13, n. 6, p. 1521-1521, 2021. DOI: 10.1007/s12551-021-00844-3

    Abstract: In vitro cell cultures are a well-known controlled test system used to analyze tumor physiologic responses upon negative stimuli. Updated techniques, us-ing three-dimensional organization of cells in cultures, are being increasingly used to this purpose. Research organizations and industry are striving to pro-duce in vitro tumor surrogates that could be better test systems to antitumor agents as new compounds or to study radiation effects on cancers. The presentation will show some techniques currently used to build and maintain these specific cell cultures, and how experiments are evolving towards the production of tumoroids, or tumoral organoids, which will include various cell types and additive manufacturing.

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  • IPEN-DOC 28615

    LIMA, MAYELLE M.P. ; NASCIMENTO, PAMELA F. do ; NASCIMENTO, ANA C.G. ; VIEIRA, DANIEL P. . A simple and quick method to generate in vitro tridimensional tumor bodies from a human breast adenocarcinoma (MCF7) using magnetic aggregation technique. Biophysical Reviews, v. 13, n. 6, p. 1470-1470, 2021. DOI: 10.1007/s12551-021-00845-2

    Abstract: INTRODUCTION Tumor physiology studies have to rely on efficient and representative models, as animal-based or in vitro tridimensional cell constructs. The work used magnetite (Fe3O4) nanoparticles produced by electron-beam induced chemical reduction to give cells the ability to form aggregates when submitted to a magnetic field, and thus to produce micro tumors in vitro. OBJECTIVES The work aimed to produce human breast adenocarcinoma mini tumors (BAMT's) in vitro. MATERIALS AND METHODS Paramagnetic iron oxide nanoparticles (PION’s) were synthesized through electron-beam induced Fe3+ reduction and subsequent coprecipitation. Due to its poly-L-lysine coating, PION’s were adsorbed on cell membranes ofMCF7 (human breast adenocarcinoma). Cells were seeded in 24-well cell culture plates pre-treated overnight with Pluronic® F-127 to prevent cell adhesion and kept in culture conditions under magnetic fields for at least 6 days. BAMT's were differentially stained with Hoescht 33342 and ethidium bromide and imaged by wide-field fluorescence microscopy. DISCUSSION AND RESULTS BAMT's appeared as integer and well-defined cellular aggregates, with sparse dead cells stained by ethidium bromide. These structures can be further used for in vitro tumor studies, as BAMT’s are supposed to be more reliable models than monolayer cultures. Treatment of wells with poloxamer caused a mild to moderated cell-repellent effect, similar to those found in commercially available products, only by a fraction of the cost. CONCLUSION The experiments succesfully produced mini tumors prone to be used in in vitro studies.

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  • IPEN-DOC 28976

    SILVA, MARIA E. da C. ; RODRIGUES, RENATA B. ; ULIAN, ANDRESSA A.. Revisão das propriedades metabólicas do Bacillus subtilis e suas aplicações biotecnológicas favoráveis à biocenose. Revista Multidisciplinar em Saúde, v. 2, n. 2, 2021. DOI: 10.51161/rems/1157

    Abstract: Introdução: O gênero Bacillus é considerado um grupo altamente heterogêneo de bactérias, catalogadas em 268 diferentes tipos de espécies e 7 subespécies, tem formato de bastonete e pertence a família Bacilaceae. Ações dessa bactéria não se limitam à promoção da saúde humana, se estendem a macro benefícios no ecossistema e, a consolida como ferramenta no combate ao desequilíbrio ambiental. Mediante os expressivos benefícios, algumas espécies se tornaram foco de relevantes estudos, como o Bacillus subtilis. Essa espécie possui características categóricas, como, pertencem as rizobactérias Gram-positivas e promotoras de crescimento de plantas, termófila, saprófita, produz catalase positiva, não patogênica e capaz de realizar esporulação para manutenção de sua demanda metabólica e inibe a esporulação de fungos. Além disso, sintetiza biossurfactantes e antibióticos com diversas aplicabilidades biotecnológicas, principalmente na biorremediação de solos e água contaminados. O B. subtilis expressa algumas características antimicrobianas, incluindo antifúngicas, e até mesmo nematicidas, esta última característica foi a menos subestimada, considerando as aplicações de tratamento para doenças de nematoides. Enfatizando a produção dos diversos antibióticos, entre eles, lantibióticos e outros, gerados de forma não ribossômica, outras substâncias secundárias, como os compostos policetídeos com propriedade farmacológica, conhecida popularmente por claritromicina e azitromicina. Um exemplo de antibiótico polipeptídico produzido pelo B.subtilis é a bacitracina. Objetivo: Elucidar a ação antimicrobiana e biossurfactantes do B.subtilis, caracterizando-as como propriedades singulares de seu metabolismo que contribuem na síntese de produtos biotecnológicos sem acometer o meio ambiente. Metodologia: Revisão bibliográfica sistemática em sites como: Pubmed, scielo e sciencedirect, utilizando os descritores: “Bacillus subtilis”, “biossurfactantes” e “antimicrobianos”. Resultados: Através da revisão literária foi possível observar um padrão das informações a respeito do Bacillus subtilis que foram tanto como estáveis em suas relações como de suas causalidades, gerando uma nova visão à biotecnologia a favor da vida. Conclusão: Partindo da premissa de que o B.subtilis é uma espécie promotora do equilíbrio da biocenose, essa revisão possibilitou unir informações à nova perspectiva da capacidade promotora do seus metabólitos, principalmente os biossurfactantes e os antimicrobianos que possuem inúmeras aplicabilidades biotecnológica e, a sua coexistência para o fazer o bem à biocenose.

    Palavras-Chave: bacteria; bacillus subtilis; biotechnology; metabolites; ecosystems

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  • IPEN-DOC 28610

    PINTO, MAYARA S. ; SILVA, CAMILA R. ; SALVEGO, CAMILA de A. ; SIMOES, MARTHA R. . Red LED irradiation impacts the cytotoxic response of murine breast cancer cells to ionizing radiation. Biophysical Reviews, v. 13, n. 6, p. 1385-1385, 2021. DOI: 10.1007/s12551-021-00845-2

    Abstract: INTRODUCTION Breast cancer is a disease of worldwide importance since it is considered the 5th leading cause of cancer deaths. Triple-negative breast cancer (TNBC) is a molecular subtype that presents resistance to conventional radiotherapy, demanding high doses of ionizing radiation (IR) for a prolonged period of treatment. On the other hand, low-level light irradiation (LLLI) has been studied to sensitize cells before IR exposure. However, the literature is poor regarding the association of both techniques in TNBC cells. OBJECTIVES Thus, we aimed to assess the effect of LLLI before IR exposure on two TNBC cell lineages. MATERIALS AND METHODS MDA-MB-231 (human TNBC) and 4T1 (murine TNBC) were cultivated, seeded at a density of 2.5 x 10 5 cells/cm², and maintained in an incubator (37ºC, 5% of CO2) overnight. LLLI was performed with a red LED (λ= 660 ± 11 nm, 38.2 mW/cm²) delivering energies of 1.2 J and 6.0 J. One-h after LLLI, the cells were submitted to both 2.5 and 5.0 Gy doses from a 60 CO source. After 24-h, mitochondrial activity (MA) was quantified by MTT assay with n= 9/group. DISCUSSION AND RESULTS Our data showed that 4T1 cells exposed to LLLI at 1.2 J exhibited higher MA than cells exposed to IR2.5. In contrast, cells exposed to 6 J of LLLI showed lower MA than IR5. Concerning MDA-MB231 cells, no statistically significant differences were noticed among groups regardless of IR and LLLI doses. CONCLUSION These findings indicate that LLLI before IR could sensitize only murine breast cancer. Besides, an appropriate combination of IR and LLLI doses seems to play a role to kill TNBC cells.

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  • IPEN-DOC 28609

    SOUZA, MARESSA D.F. de ; ITRI, ROSANGELA; RIBEIRO, MARTHA S. . Reconstitution of Leishmania plasma membrane to understand the photodynamic effect. Biophysical Reviews, v. 13, n. 6, p. 1384-1384, 2021. DOI: 10.1007/s12551-021-00845-2

    Abstract: INTRODUCTION Leishmaniasis is an important neglected disease. Photodynamic therapy (PDT) has been used to fight cutaneous leishmaniasis showing good results. However, PDT mechanisms in Leishmania parasites are not yet completely clarified. OBJECTIVES In this work, our objective was to develop a protocol to produce giant plasma membrane vesicles (GPMVs) from Leishmania amazonensis promastigotes to understand the mechanisms of action of methylene blue (MB)-mediated PDT on the cell membrane of parasites. MATERIALS AND METHODS For membrane extraction, several techniques were tested. The osmotic shock was the technique that presented the best yield and effectiveness. Phosphate and protein measurements were performed to confirm membrane extraction. For the growth of GPMVs, the best technique was electroforming using different frequencies and voltages in 4 cycles. Reconstituted GPMVs were observed by phase-contrast light microscopy. Subsequently, PDT was applied to GPMVs dispersed in an aqueous solution containing 50 μM MB and we verified the changes in permeability before and after exposure to light. The same processwas applied to giant unilamellar vesicles (GUVs) with lipid compositions similar to the parasite membrane. DISCUSSION AND RESULTS The electroforming technique with the protocol developed in this work made it possible to obtain GPMVs froma promastigote membrane isolate of L. amazonensis. The membrane isolation technique was effective to extract the parasite's membrane while preserving lipids and proteins. In GUVs we observe an increase in the area during PDT in different compositions and loss of contrast. The GPMVs showed a loss of contrast as well as the GUVs but did not show an increase in area. CONCLUSION This factor could be explained by the high degree of complexity of the membrane, which contains membrane proteins in addition to containing lipids.

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  • IPEN-DOC 28620

    ZEZELL, DENISE M. . Radiation Technology in Health Sciences at IPEN: a multidisciplinary and interdisciplinary Professional Master Degree. Biophysical Reviews, v. 13, n. 6, p. 1531-1531, 2021. DOI: 10.1007/s12551-021-00844-3

    Abstract: INTRODUCTION The Professional Master Program in Radiation Technology in Health Sciences (MP-TRCS) of the Nuclear and Energy Research Institute- IPEN/CNEN is a new program, started in August 2019. It is the only graduation program in the country to offer two nuclear reactors for educational purposes, for the development of dissertations, in addition to providing radiopharmaceuticals production in a nuclear reactor, in linear accelerator for radioisotope production, as well light and lasers applications. In addition to the infrastructure, the program has multidisciplinary training advisors working in an interdisciplinary manner who use their vast experience in radiation applied to medicine to guide students in a productive manner with a high degree of excellence. OBJECTIVES The MP-TRCS aims to fulfil a growing demand at IPEN/ CNEN from professionals working in hospitals and clinics, using ionizing and non-ionizing radiation. MATERIALS AND METHODS These students need a more dynamic course directed to the practical professional activities. We have students from the most diverse areas, such as medical doctors, biomedical doctors working in clinical analyses, radiotherapy physicists, physiotherapists, dentists specializing in imaging diagnosis and laser, among others, participating in the front line, who use radiation or assess its impact on their day-today routine. DISCUSSION AND RESULTS The first students have already begin to present their dissertation. The employability has increased among students enrolled in the program. CONCLUSION These professionals bring their experience to the program, which together with IPEN's academic structure and advisors, result in skilled students who are finding numerous career opportunities in the job market.

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  • IPEN-DOC 28612

    SEPULVEDA, ANDERSON F.; FRANCO, MARGARETH ; YOKAICHIYA, FABIANO; ARAUJO, DANIELE de. POLYana: a new software for rheological study of polymeric colloidal materials. Biophysical Reviews, v. 13, n. 6, p. 1464-1465, 2021. DOI: 10.1007/s12551-021-00845-2

    Abstract: INTRODUCTION POLYAna is a new executable software developed by SISLIBIO group for rheological analysis of hydrogel and organogel systems and other colloidal materials (nanoparticles and micelles). The software development aims to facilitate the analysis of rheology data associated to both temperature- and frequency-dependent analysis, viscosity and curve flow profiles. OBJECTIVES The software development aims to facilitate the analysis of rheology data associated to both temperature- and frequency-dependent analysis, viscosity and curve flow profiles. MATERIALS AND METHODS From raw data, several models are applied like power-law model for frequency response and curve flow, Boltzmann law to calculate gelation temperature and viscosity response under temperature,Maxwell model to study interchain relationships in addition to other models such as Bingham model, Cross model, and Herschel-Bulkley are also available. POLYana outputs calculates rheological parameters like consistency, adhesion, hysteresis, flow index, G’/G” ratio. DISCUSSION AND RESULTS To validate results obtained from POLYana, same data were analyzed by applying other programs and same mathematical models. In this sense, rheological analysis of Poloxamer 407 in water solution (15 %) were performed: from temperature-dependent G’ and G” analysis were obtained gelation temperature of 45.46 ± 0.02 °C, η_0 = 0.08 ± 0.03 mPa*s, η_max = (32.44 ± 0.17) mPa*s and dη/dT = (1.27 ± 0.02) mPa*s/°C by fitting Boltzmann law (R2 = 0.998), which are similar to results obtained by others softwares and found in literature. From temperature-dependent G’ and G” analysis, it gets adhesion value of (1647.15 ± 18.01) mPa*sn calculated from power-law model (R2 = 0.869), also similar to PRISM results. CONCLUSION Also, other Poloxamer concentrations and hydrogels types have been evaluated, showing close numbers to that previously reported. In order to stablish structural relationships, one of POLYana tools is also to analyze small-angle neutron scattering (SANS) and develop Monte Carlo simulation for SANS and rheological analysis, simultaneously.

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  • IPEN-DOC 28611

    SILVA, CAMILA R. ; PINTO, MAYARA S. ; RIBEIRO, MARTHA S. . Photodynamic therapy associated with ionizing radiation in the treatment of triple-negative breast cancer cells. Biophysical Reviews, v. 13, n. 6, p. 1386-1386, 2021. DOI: 10.1007/s12551-021-00845-2

    Abstract: INTRODUCTION Breast cancer is the most common cancer for women worldwide. According to the World Health Organization, it is considered the 5 th leading cause of death from cancer. Triple-negative breast cancer (TNBC) is a subtype of this disease that represents around 20% of all invasive breast cancer, whose main characteristics are resistance to conventional treatments, such as exposure to ionizing radiation (IR). On the order hand, the photodynamic therapy (PDT) using porphyrins and their derivatives has been described in the literature as a potential therapy against cancer. OBJECTIVES Thus, our goal in this work was to associate PDT and IR in the treatment of TNBC. MATERIALS AND METHODS MDA-MB-231 cells at a concentration of 2x104 cells were submitted to PDT using TMPyP porphyrin (30 μM) and a red light (660 ±11 nm) with fluences of the 23 and 57.5 J/cm 2 (57.3 mW/cm 2). Immediately post-PDT, cells were divided into groups: non-treated (control), only IR and PDT associated with IR (PDT57+IR and PDT23+IR) and then, exposed to IR with a dose of 2.5 Gy. Past 24-h of the PDT-session, the cell viability, clonogenicity and total glutathione were verified. DISCUSSION AND RESULTS Cells exposed to IR not presented statistically significance difference compared to the control group. However, treated groups showed around 38% lower cell viability in relation to the control and IR groups. For the clonogenic assay a reduction of the approximately 65% was observed between IR and treated groups. Regarding to the total glutathione, all groups showed an increase when compared to control group. Nonetheless, no were identified differences between IR and treated groups. CONCLUSION Taken together, our results indicate that PDTassociate with IR may be an ally in TNBC treatment.

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  • IPEN-DOC 28605

    SANTOS, CAROLINA M. dos ; SAMPAIO, SUELEN de B.; SANTANA, FAGNER ; LEITE, RODRIGO C. ; PRATA, BEATRIZ A. ; AFFONSO, REGINA . A new approach for purification of the catalytic site of the Angiotensin Conversion Enzyme, N domain, mediated by the ELP-Inten system. Biophysical Reviews, v. 13, n. 6, p. 1305-1305, 2021. DOI: 10.1007/s12551-021-00845-2

    Abstract: INTRODUCTION Angiotensin-converting enzyme I, ACE, is a key part of the renin-angiotensin system whose main function is to regulate blood pressure and balance of salts in the body. ACE1 has two isoforms, somatic, sACE, and testicular, tACE. sACE possesses two domains, N- C-, with catalytic sites which exhibit 60% sequence identity. These domains differ in terms of chloride-ion activation profiles, rates of peptide hydrolysis and sensitivities to various inhibitors. N-domain has specific action in the hydrolyze of Alzheimer’s diseases beta amyloid bodies and angiotensin 1-7, which active the MAS receptor and triggering anti-thrombotic and anti-inflammatory actions. OBJECTIVES The objective this work was to obtain catalytic site Ala361 to Gli468 of the N-domain region, csACEN, isolation without chromatographic and denaturant chemical process. MATERIALS AND METHODS For that, a new methodology was used in the expression of the csACEN peptide, in which the peptide was linked to the elastin-like polypeptide, ELP, and Intein, and expressed at 37C. The characterization of catalytic site was made by SDS-PAGE and dot blotting. DISCUSSION AND RESULTS The culture temperature at 37C significantly increased the expression of the ELP/Intein/csACEN fusion protein. This culture was lysed at a low temperature allowing the fusion protein to become soluble. The precipitation of ELP at high concentrations of ammonium sulfate were obtained in 0.57 M and 0.8 M. Intein autocleavage occurs at acidic pH and it is important to pay attention to: pI 6.65 for csACEN and pI 6.87 for ELPcsACEN, which are very low. The best autocleavage efficiency was withMES and TriHCl buffers, pH 6.3 and 6.8, respectively, in which pure csACEn peptide was obtained. CONCLUSION The strategy used to obtain the Ala361 to Gli468 catalytic site in soluble and pure form was obtained with success and the protocol for obtaining similar peptides was established.

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  • IPEN-DOC 28607

    CONTATORI, CAROLINA G. de S. ; PINTO, MAYARA S. ; RIBEIRO, MARTHA S. . Melanoma cell migration in response to red and near-infrared low-level light. Biophysical Reviews, v. 13, n. 6, p. 1380-1380, 2021. DOI: 10.1007/s12551-021-00845-2

    Abstract: INTRODUCTION Cell migration plays an important role in tissue formation and cancer progression. In vitro scratch assay has been used for many years to study cell migration to mimic the migration of in vivo cells, and, thus, to evaluate cancer growth. Low-level red and near-infrared light (LLL) can increase normal cell migration. However, the impact of LLL on tumor cells remains unclear. OBJECTIVES In this work, we aimed to evaluate the effects of a single LLL dose on melanoma cell migration. MATERIALS AND METHODS B16F10 (murine melanoma) cells were cultivated in RPMI medium with 10% of fetal bovine serum until they reached 80% confluency. The cell line was seeded in a 6-well plate at a density of 2x10 5 cells/well in triplicate at two different moments. A wound scratch was performed to disrupt the confluent cellmonolayerwith a 10 μL pipette tip. Immediately after the injury, the cells were submitted to the LLL at two distinct wavelengths (660 and 780 nm) provided by a LED and a laser, respectively, delivering 3 different energies (1.3, 3.6, and 6 J) at an irradiance of 4.2 mW/cm 2 . The control group was not irradiated. Cells were photographed immediately and at 3, 12, 24, and 36 h after the scratch. The wound closure was measured using ImageJ software. To evaluate the overall migration, we calculated the areas under the curve for each group. DISCUSSION AND RESULTS Cells exposed to the red laser at 6 J migrated slower than control. In contrast, LLL at 780 nm promoted faster cell migration when irradiated with 3.6 J. CONCLUSION These results suggest that low-level LEDs at 660 nm could prevent melanoma progression in higher energies. However, 780 nm should be avoided at middle energies.

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  • IPEN-DOC 28617

    YOSHIMURA, TANIA M. ; SAUTER, ISMAEL P. ; RIBEIRO, MARTHA S. . Low power light triggers opposite effects on stem cells: influence of the wavelength and culture conditions. Biophysical Reviews, v. 13, n. 6, p. 1492-1493, 2021. DOI: 10.1007/s12551-021-00844-3

    Abstract: INTRODUCTION Photobiomodulation (PBM) has been gaining importance in a wide range of medical fields in the past few years, particularly in stem cell-based regenerative medicine. Improving in vitro cell proliferation, differentiation and viability are ways where PBM could play a pivotal role optimizing biotechnological and bioengineering applications. OBJECTIVES Here we investigated whether different wavelengths (blue, green and red) would promote distinct outcomes in human adipose-derived stem cells (hADSCs) cultured in regular and supplemented media for tenocyte differentiation. MATERIALS AND METHODS Freshly isolated hADSCs were cultured in a specific stem cell medium (MSCGM, Lonza), DMEM or a tenogenic medium (TEN-M: DMEM supplemented with growth factors and ascorbic acid). Cells were irradiated every 48 h (23.28 mW/cm 2 , 17 min 10 s delivering 24 J/cm 2 per session) using a LED irradiator (LEDbox, BioLambda). MTT and crystal violet assays were used to evaluate cell metabolic activity and proliferation. DISCUSSION AND RESULTS Red wavelength (660 nm) significantly increased metabolic activity after five irradiations, but only for cells cultured in TEN-M. Oppositely, blue (450 nm) and green (520 nm) light decreased both cell proliferation and metabolic rate, with more pronounced effects for blue light in TEN-M. Considering these findings, we examined whether irradiating only the media would generate toxic compounds that could impair cell viability. We therefore assessed reactive oxygen species (ROS) production by p-nitrosodimethylaniline/histidine assay while irradiating the three different media under the same conditions as mentioned above. Immediately after blue and green light exposure, an increment in ROS production was observed for DMEM and TEN-M, that continuously increased until reaching between 4.5 and 7.1 μM one-hour after irradiation – with higher values for TEN-M exposed to blue light. CONCLUSION Since no significant ROS formation was observed following red light exposure, we concluded that medium composition was responsible for the different effects on metabolic activity and proliferation observed after irradiation with different wavelengths.

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  • IPEN-DOC 28616

    RIBEIRO, MARTHA S. . Light-based non-thermal therapy: from basis to clinical applications. Biophysical Reviews, v. 13, n. 6, p. 1491-1491, 2021. DOI: 10.1007/s12551-021-00844-3

    Abstract: Light-based non-thermal therapies are evolving as promising non-invasive and cost-effective medical technologies. These therapeutic platforms mainly encompass photobiomodulation (PBM) and photodynamic therapy (PDT), which use visible or near infrared (NIR) light to induce biological responses without any significant heating effects. For PBM, it is most commonly used red or NIR light to optimize light penetration into biological tissues. The photon absorption by natural chromophores at these spectral regions cause photophysical and photochemical reactions inside cells that trigger several biological effects such as to accelerate wound healing, reduce inflammation and relief pain, depending on light parameters and target tissue. On the other hand, PDT makes use of photoactivated drugs, also called as photosensitizers, which absorb light to induce chemical reactions that kill microbial or cancer cells by oxidative stress. Our group have been investigating the mechanisms and several applications of PBM and antimicrobial PDT (APDT) for almost 20 years. In this lecture I will share our experience in the area to discuss how PBM and APDT could be used to revolutionize health care in the photonics era. An integrated perspective from the basic mechanisms, preclinical and clinical trials for both therapies will be presented, including PBM on cancer management and APDT against drug-resistant pathogens. The lecture will also highlight future perspectives.

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  • IPEN-DOC 28604

    TREMARIN, BEATRIZ; YOKAICHIYA, FABIANO; KELLERMANN, GUINTHER; FRANCO, MARGARETH K.K.D. ; STORSBERG, JOACHIM. Improvement of the methodological strategies to product functionalizes antibodies using Small Angle Neutron Scattering (SANS). Biophysical Reviews, v. 13, n. 6, p. 1301-1301, 2021. DOI: 10.1007/s12551-021-00845-2

    Abstract: INTRODUCTION Antibodies are used by jawed vertebrates for defense against invading pathogens. Usage of those versatile tools in a plethora of settings in clinics and biomedical sciences hinges on functionalization strategies that retain native antibody reactivity. To this date, antibody functionalization is performed by trial and error. OBJECTIVES We aim to reduce costs by providing general principles to allow the full spectrum of antibody functionalization by correlating functionalized antibody reactivity to cognate antigen by small angle neutron scattering, SANS, measurements and mathematical modeling of antibody and antibody-antigen super-complexes, obtained by titration experiments. MATERIALS AND METHODS For this research we have used for as antibody pure goat anti rabbit immunoglobulin, and for the antigen, pure Horseradish Peroxidase Preliminary results show that the systems (antibody and antibody-antigen complexes) do not change in the range of a temperature related to storage temperature (25º C), body temperature (37º C) and 40º C. DISCUSSION AND RESULTS These results will give us the pair distribution function of these systems and the results will be viewed in light of published precedence to highlight areas where future effort is needed to refine such versatile tools and improve their production. However, between the antibody and the complexes structure, different conformations were observed. The antibody has a globular structure with a radius of gyration around 33 Å, and the complexes display an elongated cylindrical shape with radius of gyration around 63 Å. CONCLUSION This study shows how the scattering techniques (SANS) can provide useful information about the conformation of the antibody and antibody-antigen formation and help to shed light in the understanding the physical, chemical, and structural changes on the organization of these important antibody functionalization for the immunological system.

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  • IPEN-DOC 27820

    PETERSEN, ALAN; TACCHEO, STEFANO; MIROV, SERGEY; NILSSON, JOHAN; PASK, HELEN; SARACENO, CLARA; WETTER, NIKLAUS ; WU, RUIFEN. Focus issue introduction: Advanced Solid-State Lasers 2020. Optics Express, v. 29, n. 6, p. 8365-8367, 2021. DOI: 10.1364/OE.423636

    Abstract: This Joint Issue of Optics Express and Optical Materials Express features 15 articles written by authors who participated in the international online conference Advanced Solid State Lasers held 13–16 October, 2020. This review provides a summary of the conference and these articles from the conference which sample the spectrum of solid state laser theory and experiment, from materials research to sources and from design innovation to applications.

    Palavras-Chave: lasers; solid state lasers; radiation sources; meetings

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  • IPEN-DOC 27819

    PETERSEN, ALAN; TACCHEO, STEFANO; MIROV, SERGEY; NILSSON, JOHAN; PASK, HELEN; SARACENO, CLARA; WETTER, NIKLAUS ; WU, RUIFEN. Focus issue introduction: Advanced Solid-State Lasers 2020. Optical Materials Express, v. 11, n. 4, p. 952-954, 2021. DOI: 10.1364/OME.423641

    Abstract: This Joint Issue of Optics Express and Optical Materials Express features 15 articles written by authors who participated in the international online conference Advanced Solid State Lasers held 13–16 October, 2020. This review provides a summary of the conference and these articles from the conference which sample the spectrum of solid state laser theory and experiment, from materials research to sources and from design innovation to applications.

    Palavras-Chave: lasers; solid state lasers; radiation sources; meetings

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  • IPEN-DOC 28606

    MITSUTAKE, HERY; SOUZA, ALESSANDRO D. de; YOKAICHIYA, FABIANO; FRANCO, MARGARETH K.K.D. ; CLEMENS, DANIEL; KENT, BEN; BREITKREITZ, MARCIA C.; RIBEIRO, LIGIA N. de M.; PAULA, ENEIDA de; BORDALLO, HELOISA N.. Evaluation of structural changes of benzocaine-loaded, optimized nanostructured lipid carriers using SANS and Raman imaging approaches. Biophysical Reviews, v. 13, n. 6, p. 1335-1335, 2021. DOI: 10.1007/s12551-021-00845-2

    Abstract: INTRODUCTION Local anesthetics are substances that reversibly block the nerve-impulse conduction, alleviating pain without loss of consciousness. Benzocaine, a poorly soluble local anesthetic, is an ester of para-aminobenzoic acid. Several strategies of formulations can be used to improve bioavailability and decrease adverse effects of benzocaine. In this study nanostructured lipid carriers (NLC) were employed. These lipid-based drug delivery carriers have a lipid core composed of a blend of solid and liquid lipids, and a shelf of non-ionic surfactant. OBJECTIVES The main aim of this work was to optimize benzocaine-loaded NLC and to investigate structural changes in these nanoparticles, under different temperatures. MATERIALS AND METHODS The ratio of excipients (cetyl palmitate, Capmul® PG-8 NF and Pluronic®F68) and benzocaine in the NLC was optimized using a 2 3 factorial design with respect to the following parameters: particle size, polydispersity index (PDI) and zeta potentials. DISCUSSION AND RESULTS The interactions between the factors were found relevant to determine particle size and PDI. Using desirability function, the best formulation conditions were found. Structural changes in optimized NLC were observed with Small-Angle Neutron Scattering (SANS) and Raman imaging, in samples at 27, 37 and 40º C. SANS pointed the formation of lamellar structures inside the NLC, which interlamellar distances increase at higher temperature. Raman imaging showed that the incorporation of P68 and benzocaine in-between the lipids increased at higher temperatures, explaining the changes in Q values (SANS). CONCLUSION This work shows how different scattering techniques can provide complementary information and be used together to characterize and understand the physical, chemical, and structural changes on the organization of pharmaceutical carriers in drug delivery system.

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  • IPEN-DOC 28614

    SANTOS, CAROLINA S.F. dos ; BELLINI, MARIA H. ; SANTOS, SOFIA N. dos ; ARAUJO, ELAINE B. de . Estudo sobre a eficiência do radiofármaco PSMA-1007-18F na detecção do câncer de próstata em um estudo pré-clínico in vivo. Biophysical Reviews, v. 13, n. 6, p. 1467-1467, 2021. DOI: 10.1007/s12551-021-00845-2

    Abstract: INTRODUCTION O PSMA-1007-18F é caracterizado por uma biodistribuição única em comparação com outros agentes de PSMA, pois é eliminado através do fígado, além de ter captação elevada dentro das células do câncer de próstata. OBJECTIVES O objetivo deste trabalho é analisar a especificidade do radiofármaco PSMA-1007-18F em camundongos com modelo tumoral PSMA+ através de um estudo de bloqueio. MATERIALS AND METHODS Animais SCID com células tumorais LNCaP foram preparados e divididos em quatro grupos (n=5) de acordo com os tempos de biodistribuição de 30 minutos, uma hora, duas horas e uma hora com agente bloqueador PSMA I&T (100μg/μL), sendo injetado 30 minutos antes do radiofármaco. Foram injetados 5,55 MBq (0,056 MBq/μL) via caudal nos animais e após os tempos pré-determinados foram sacrificados, com os órgãos de interesse coletados, pesados e sua atividade contabilizada. As imagens PET/CT foram realizados para ilustrar a captação do PSMA-1007-18F pelo tumor e por órgãos PSMA+ com e sem bloqueio. DISCUSSION AND RESULTS O grupo de 30 minutos apresentou maiores captações, caracterizando o estágio de distribuição. Rins e baço apresentaram alta captação pelo PSMA-1007-18F por serem PSMA+, onde sua especificidade pode ser constata pela drástica diminuição de captação nos animais com agente bloqueador. A captação pelas células tumorais de próstata se mostrou constante durante o período avaliado e foi efetivamente bloqueada pelo excesso de PSMA I&T (imagem), que confirma a ligação do radiofármaco aos receptores de PSMA. Apesar de apresentar uma baixa hidrofilicidade, a razão entre tumor/sangue e tumor/músculo foi de 14,18 ± 3,19 e 4,78 ± 1,52 em 1h, respectivamente. CONCLUSION O radiofármaco PSMA-1007-18F apresenta propriedades de ligação que fornecem captação tumoral específica. Sua viabilidade em imagens para câncer de próstata foi demonstrada pela alta especificidade pelas células PSMA+ e pela via de excreção hepatobiliar. Os resultados deste estudo serão úteis para subsidiar o registro e comercialização deste radiofármaco.

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  • IPEN-DOC 28608

    SOUZA, TIAGO H. dos S.; ANDRADE, CAMILA; CABRAL, FERNANDA ; SARMENTO-NETO, JOSE; REBOUCAS, JULIO; SANTOS, BEATE; RIBEIRO, MARTHA ; FIGUEIREDO, REGINA; FONTES, ADRIANA. Effects of photodynamic inactivation mediated by Zn(II) porphyrin on promastigote and amastigote forms of Leishmania amazonensis. Biophysical Reviews, v. 13, n. 6, p. 1380-1381, 2021. DOI: 10.1007/s12551-021-00845-2

    Abstract: INTRODUCTION Photodynamic inactivation (PDI) has been attracting attention as an innovative technology to treat topical diseases, such as cutaneous leishmaniasis (CL) and infections caused by multidrug-resistant microorganisms. Zn(II) meso-tetrakis(N-n-hexylpyridinium-2-yl)porphyrin (ZnTnHex-2-PyP 4+ ) is a lipophilic water-soluble Zn(II) porphyrin with improved photophysical properties, high chemical stability, and cationic/ amphiphilic character that can enhance its interaction with cells. OBJECTIVES Thus, this study aimed to investigate the PDI effects mediated by ZnTnHex-2-PyP 4+ on Leishmania amazonensis. MATERIALS AND METHODS Confocal fluorescence microscopy was explored to study the interaction of ZnTnHex-2-PyP 4+ with promastigotes. The PDI action was analyzed by cell membrane integrity, mitochondrial membrane potential (ΔΨm), and cell morphology. Promastigotes were incubated with ZnTnHex-2-PyP 4+ for 5 min at 0.62 and 1.25 μM and irradiated by a LED (410 nm) for 1 or 3 min (2.3 and 3.4 J/cm 2 , respectively). PDI on amastigotes and the cytotoxicity onmacrophages were also analyzed (3.4 J/cm 2 ). DISCUSSION AND RESULTS Fluorescence microscopy revealed that parasites efficiently uptake ZnTnHex-2-PyP 4+ and displayed a punctate labeling pattern along with the cytoplasm. An intenseΔΨmdepolarization was also observed, which in association with microscopy results, suggests that ZnTnHex-2-PyP 4+ may accumulate in the mitochondrion, or other well-defined structures close to it. Moreover, ZnTnHex-2-PyP 4+ at concentration as low as 0.62 μM led to the immediate inactivation of >95% of promastigotes, regardless of the light dose used. Loss of the fusiform shape and plasma membrane wrinkling were also observed. After a single treatment session in amastigotes, PDI led to a reduction of 70% in the infection index. No considerable toxicity was observed on mammalian cells. CONCLUSION Thus, PDI of Leishmania parasites showed in vitro efficiency at a submicromolar concentration of ZnTnHex-2-PyP 4+ , with short pre-incubation and irradiation times. The results encourage further studies in CL pre-clinical assays and PDI of other microorganisms.

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  • IPEN-DOC 28613

    NASCIMENTO, ANA C.G. ; GALISTEO JUNIOR, ANDRES J.; SILVA, GIOVANA D. da ; ROCHA, LEONARDO W.P. de S. ; VIEIRA, DANIEL P. . Effective methodology for maintaining Toxoplasma gondii in vitro using paramagnetic iron nanoparticles to support three-dimensional cell culture. Biophysical Reviews, v. 13, n. 6, p. 1466-1466, 2021. DOI: 10.1007/s12551-021-00845-2

    Abstract: INTRODUCTION Toxoplasma gondii is a protozoan parasite that infects approximately one billion people worldwide. Upon infection, the host may die due to latent infection or presence with chronic cysts in brain, retina or muscle tissue. Humans can become infected consuming water or foods contaminated with oocysts or eating undercooked meat. Its virulent form is difficult to replicate in vitro, requiring additional steps using experimental animals. The use of nanotechnology can contribute to this in vitro production, through the three-dimensional cultivation of mouse fibroblast cells (NIH / 3T3 ATCC ® CRL-1658™) and nanoparticles synthesized with radiation. OBJECTIVES The objective of this work was to demonstrate the three-dimensional culture of fibroblast cells aggregated to nanoparticles for inoculation the T. gondii. MATERIALS AND METHODS This methodology was created to facilitate parasite management and replication. For the production of nanoparticles, the work used concentrations of iron sulfate II heptahydrate (Fe2SO4.7H2O, CAS 7782-63-0) and glycine (NH2CH2COOH, CAS 56-40-6) diluted in ultrapure water free ofO2 at pH 12. This solutionwas irradiated by electron beam of the IPEN / CNEN-SP Radiation Technology Center in doses of at least 15 and at most 30kGy. Paramagnetic iron oxide nanoparticles (PION’s) were then adsorbed on cell membranes, and cells were kept together by a magnetic field. Structured spheroids (4 day of culture) were infected with 106 parasites (RH strain) and the infection was evaluated by transmission electron microscopy. DISCUSSION AND RESULTS Tachyzoiteswere found inside 3T3 cells, assuring that the spheroid can be a suitable culture substrate to T. gondii in vitro propagation. CONCLUSION A three-dimensionalmethodology for in vitro cultivation of the parasite is perhaps the key for applications in the study of toxoplasmosis, as it has a fast, cheap, efficient production (yield and reduction of contamination).

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A pesquisa no RD utiliza os recursos de busca da maioria das bases de dados. No entanto algumas dicas podem auxiliar para obter um resultado mais pertinente.

✔ É possível efetuar a busca de um autor ou um termo em todo o RD, por meio do Buscar no Repositório , isto é, o termo solicitado será localizado em qualquer campo do RD. No entanto esse tipo de pesquisa não é recomendada a não ser que se deseje um resultado amplo e generalizado.

✔ A pesquisa apresentará melhor resultado selecionando um dos filtros disponíveis em Navegar

✔ Os filtros disponíveis em Navegar tais como: Coleções, Ano de publicação, Títulos, Assuntos, Autores, Revista, Tipo de publicação são autoexplicativos. O filtro, Autores IPEN apresenta uma relação com os autores vinculados ao IPEN; o ID Autor IPEN diz respeito ao número único de identificação de cada autor constante no RD e sob o qual estão agrupados todos os seus trabalhos independente das variáveis do seu nome; Tipo de acesso diz respeito à acessibilidade do documento, isto é , sujeito as leis de direitos autorais, ID RT apresenta a relação dos relatórios técnicos, restritos para consulta das comunidades indicadas.

A opção Busca avançada utiliza os conectores da lógica boleana, é o melhor recurso para combinar chaves de busca e obter documentos relevantes à sua pesquisa, utilize os filtros apresentados na caixa de seleção para refinar o resultado de busca. Pode-se adicionar vários filtros a uma mesma busca.

Exemplo:

Buscar os artigos apresentados em um evento internacional de 2015, sobre loss of coolant, do autor Maprelian.

Autor: Maprelian

Título: loss of coolant

Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

✔ Para indexação dos documentos é utilizado o Thesaurus do INIS, especializado na área nuclear e utilizado em todos os países membros da International Atomic Energy Agency – IAEA , por esse motivo, utilize os termos de busca de assunto em inglês; isto não exclui a busca livre por palavras, apenas o resultado pode não ser tão relevante ou pertinente.

✔ 95% do RD apresenta o texto completo do documento com livre acesso, para aqueles que apresentam o significa que e o documento está sujeito as leis de direitos autorais, solicita-se nesses casos contatar a Biblioteca do IPEN, bibl@ipen.br .

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ATENÇÃO!

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O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

1. Portaria IPEN-CNEN/SP nº 387, que estabeleceu os princípios que nortearam a criação do RDI, clique aqui.


2. A experiência do Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP) na criação de um Repositório Digital Institucional – RDI, clique aqui.

O Repositório Digital do IPEN é um equipamento institucional de acesso aberto, criado com o objetivo de reunir, preservar, disponibilizar e conferir maior visibilidade à Produção Científica publicada pelo Instituto, desde sua criação em 1956.

Operando, inicialmente como uma base de dados referencial o Repositório foi disponibilizado na atual plataforma, em junho de 2015. No Repositório está disponível o acesso ao conteúdo digital de artigos de periódicos, eventos, nacionais e internacionais, livros, capítulos, dissertações, teses e relatórios técnicos.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.