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  • Resumo IPEN-doc 30477
    Prevenção de cárie dental além do pH crítico, utilizando aplicação tópica de flúor e laser de Nd꞉YAG
    2023 - CARAMEL-JUVINO, A.; FONTES-OLIVEIRA, Y.R.; AVELINO, S.G.; ZEZELL, D.M.
    A aplicação tópica de flúor (ATF) demonstra 37% de redução de cárie. Considerando a cárie como um problema permanente de Saúde Pública, a busca por melhores condições preventivas é sempre incentivada. Este trabalho teve como objetivo avaliar o efeito anticárie da ATF (FFA 12.300 μF‑/g) associada à irradiação com laser de alta potência (Nd꞉YAG, 84 J/cm2) em condições diferentes de pH e a extensão da resistência ácida. 180 blocos de esmalte hígido, previamente selecionados pela microdureza de superfície, foram divididos em 4 grupos (n=45)꞉ Controle Negativo, Flúor, Laser e Flúor + Laser. Após o tratamento, cada grupo foi subdividido em 3 grupos (n=15) para simulação de cárie in vitro em diferentes condições de pH꞉ pH=5 (abaixo do pH crítico do esmalte), pH=4,5 (abaixo do pH crítico do esmalte na presença do flúor) e pH=4 (investigativo). As amostras foram avaliadas por꞉ % de perda de dureza superficial (%PDS); espectroscopia no Infravermelho por Transformada de Fourier (FTIR); Tomografia de Coerência Óptica (OCT) e Análise morfológica utilizando Microscopia Eletrônica de Varredura (MEV). Houve diferença significativa na banda do fosfato, com aumento do teor de fosfato no grupo Flúor + Laser em pH 4.5; um menor coeficiente de atenuação foi encontrado no grupo Flúor + Laser em todos os pHs, assim como menor %PDS, ambos indicam menor desmineralização (ANOVA + Teste de Tukey p<0,05). Concluiu‑se que o tratamento com Flúor (ATF) e Laser de Nd꞉YAG tem efeito preventivo além do pH crítico para o esmalte na presença do flúor isolado.
  • Resumo IPEN-doc 30476
    Um efeito inesperado do tratamento do distúrbio respiratório do sono
    2023 - MENDES, V.; AZEVEDO, L.H.; ZEZELL, D.M.
    Alguns trabalhos tem vinculado de forma questionável, a nômina de tratamento do ronco à abordagem terapêutica para tratamento dos distúrbios respiratórios do sono (DRS). Este trabalho busca verificar se os resultados obtidos de melhora no quadro respiratório com o tratamento do DRS, levam sempre à melhora do ronco. De acordo com a polissonografia e achados clínicos, o paciente do sexo masculino, 39 anos de idade, apresentava quadro compatível com ronco primário. Recebeu tratamento não ablativo com lasers Nd꞉YAG e Er꞉YAG em três sessões de aproximadamente 20 minutos, nos momentos 0, 14 e 28 dias. O paciente foi avaliado por exame de polissonografia, antes e após o tratamento. Apesar da melhora nos parâmetros de índice de dessaturação de oxihemoglobina (IDO꞉ de 3,7 para 3,1) e saturação mínima de oxihemoglobina (SpO2꞉ de 84% para 90%), que indicam melhora do quadro respiratório, houve piora da roncopatia (tempo de sono com ronco꞉ de 3% para 13%), visto que a complacência tecidual é apenas um dos fatores de risco para o surgimento e progressão dos DRS. Com os resultados obtidos, notamos que o remodelamento tecidual pelo tratamento do DRS com lasers, favorece o restabelecimento da patência faríngea, melhorando o fluxo aéreo da respiração durante o sono, observado pela melhora nos parâmetros de saturação de oxihemoglobina em polissonografia, podendo entretanto, aumentar o evento ruidoso. Portanto, o ronco pode ser visto como sinal clínico do distúrbio respiratório do sono, mas não deve ser utilizado como parâmetro exclusivo de avaliação do tratamento ou progressão da doença.
  • Resumo IPEN-doc 30475
    Modificações de superfícies de ligas de titânio e zircônio visando aplicações em implantes dentários
    2023 - LEITE, D.M.C.; ROSSI, J.L.; ZEZELL, D.M.
    No atual mercado, o uso de Ti na fabricação de implantes dentários é unanimidade, sendo que a maioria dos implantes são confeccionados em Ti G4 e Ti G5. Porém existem situações clínicas onde é necessário reduzir os diâmetros dos implantes e manter uma boa resistência mecânica. Duas ligas experimentais com Ti e Zr respectivamente com 14% e 20% de Zr % em massa, foram fundidas. O objetivo foi comparar as superfícies obtidas após tratamentos superficiais das ligas experimentais com o material comercial, e discutir os efeitos que podem alterar a osseointegração. Foram feitos nove diferentes tratamentos superficiais, com dois ácidos a diferentes concentrações e condições, com jateamento por Al2O3 seguido por condicionamento ácido e tratamento com laser pulsado de Nd꞉YAG. Os métodos utilizados nos tratamentos da superfície das amostras permitiram aumentar a rugosidade superficial, transformar as topografias e alterar a molhabilidade. Constatou‑se que as amostras possuem boa qualidade, baixo nível de impurezas e boa resistência mecânica. Pela dureza Vickers comprovou‑se que a adição de Zr aumentou a dureza em relação ao Ticp G4 e Ti G5. Portanto, as ligas experimentais podem ser indicadas para a finalidade pretendida. Os tratamentos com laser e com condicionamento com HF a 5 minutos a temperatura ambiente resultaram os melhores resultados.
  • Resumo IPEN-doc 30474
    Association of antimicrobial photodynamic therapy (aPDT) and platelet- and leukocyte-rich fibrin (L-PRF) in immediate dental implant surgery in contaminated alveoli with extensive bone loss
    2023 - MORAES, PAULO N.L. de; DIAS-MORAES, MARCIA C.; ZEZELL, DENISE M.
    In patients with extensive bone loss, dental implants are a challenge for oral rehabilitation. The presence of dental infection requires prior resolution with several surgical steps. Local decontamination after tooth extraction, using antimicrobial photodynamic therapy (aPDT – low-level laser: 660 nm, 100 mW, 60 s, 6 J, Laser Duo, MM Optics, SP/Brazil; methylene blue 0.01%, Chimiolux 10 – DMC, SP/Brazil), followed by the release of growth factors and angiogenesis stimulation achieved by the use of platelet- and leukocyte-rich fibrin (L-PRF), have the potential to reduce the number of surgical interventions, being safe for patients, even in the presence of systemic diseases. The Hounsfield index variation was evaluated using the Dental Slice software (BioParts) in cone-beam computed tomography scans, performed before and 3 months after dental implant surgery (ArcsysFGM, SC/Brazil) in patients who had extensive bone loss with the presence of local infection and underwent local decontamination with aPDT and the use of L-PRF (hydration of the xenogenous graft and membrane to protect the surgical area). The change in ROI cross-sectional areas was also compared using ImageJ software before and after 3 months. The torque evaluation with the aid of the system ratchet (35 N) was assessed after the exposure of the implants, without pain, sowing the stability of the implants. With the association of these techniques in a single surgical moment, there was osseointegration of the implants, showing the potential of this protocol in critical areas, reducing the number of surgical interventions and medications (anesthesia, antibiotics, anti-inflammatories, analgesics), improving the quality of life of patients in a reduced time interval compared to the conventional protocol. Systemically compromised patients, such as those with heart disease and diabetes, may be particularly favored.
  • Resumo IPEN-doc 30473
    Immunohistochemistry of cytokeratin proteins 10 (CK10) and 14 (CK14) demonstrates that photobiomodulation improves epithelial maturity of radiation-induced oral mucositis wounds
    2023 - SARDO, ARIANE V.N.; CORREA, LUCIANA; ZEZELL, DENISE M.
    Background. Oral mucositis (OM) is a common injury in cancer patients that can be caused by radiation therapy to the head and neck or certain chemotherapy drugs. The clinical extent of its manifestation is variable, especially when induced by ionizing radiation. In such cases, OM causes ulceration, severe pain when accompanied, risk of local and systemic infections, and increased treatment costs. There is no therapeutic consensus for the treatment of OM in recent decades. Objectives. The focus was placed on photobiomodulation (PBM) using low-intensity lasers at red and infrared wavelengths. This is a non-drug option that can ease discomfort and speed wound healing. The mechanism of action of PBMs in the evolution of OM reduction is not clear. Materials and methods. With the aim of clarifying the role of PBM in the progression of epithelial maturity in OM ulcerations induced by ionizing radiation, the present study evaluated the effect of PBM with a wavelength of red (λ), 660 nm and infrared, and 780 nm in radio-induced OM lesions, on the tongue of mice, 8 and 20 days after irradiation, in a single year, with 20 Gy, from a source of gamma lightning. The percentage area corresponding to the positive staining for cytokeratin proteins 10 (CK10) and 14 (CK14) was evaluated in the epithelial area of the lesions using the immunohistochemistry (IHC) technique, after 8 and 20 days of lesion challenge and compared to an untreated control group. The CK10 is a protein related to epithelial cells with a higher degree of maturity and differentiation. It can collaborate with the tissue’s innate defense response and was significantly more expressed in the group treated with 660-nm PBM. Discussion. The protein related to epithelial layers of lower cell maturity (CK14) is important for the resistance of the basal area of the epithelium and should be restricted to these cell layers, closer to the connective tissue in healthy epithelia. In this study, it did not show quantitative differences between groups. Its distribution pattern, however, remained altered on the 20th day of the experiment for the control group. In the groups treated with PBM, CK14 was already present with its marking delimited to the basal layer of the epithelium. Conclusions. According to the analyses obtained in the evaluated samples, the PBM treatment was able to optimize the expression of the epithelial proteins studied here and related to the epithelial maturation process.
  • Resumo IPEN-doc 30472
    Spectroscopic and texture analysis by cone beam computed tomography of dentin modified with Nd:YAG laser
    2023 - VILAS BOAS, RENATA C.; SILVA JUNIOR, JEFFERSON P. da; MENDONCA, RAFAEL P. de; SILVA, TANIA M. da; CAMPOS, TIAGO M.B.; ZEZELL, DENISE M.; GONCALVES, SERGIO E. de P.
    Objectives. The aim of this study was to evaluate the influence of the Nd:YAG laser associated or not associated with a new Curaprox black toothpaste-based photoabsorber on the chemical structure of dentin, through spectroscopic analysis (FTIR) and texture analysis by cone beam computed tomography (CBCT). Materials and methods. Thirty specimens of bovine incisor crowns were obtained and embedded in acrylic resin. Each sample was ground and polished with sandpaper until the exposure of the dentin surface, followed by the demarcation of 2 circles on these surfaces using a 3-mm diameter trephine drill, one close to the incisal and the other close to the cervical region of the tooth, to establish regions separated in dentin for different interventions in the same specimen. From the demarcations, 4 groups were obtained (n = 15): GC – control group (no surface treatment), GL – laser group (Nd:YAG laser 60 mJ/pulse, 10 Hz, 48 J/cm2, with contact and scanning for 60 s), GF – photoabsorber group (application of photoabsorber for 60 s, followed by abundant washing), GLF – photoabsorber group + laser (photoabsorber application + Nd:YAG laser 60 mJ/pulse, 10 Hz, 48 J/cm2, with contact and sweep for 60 s). Afterwards, the samples were submitted to chemical analysis by means of FTIR, where the spectra with the transmittance peaks of the main elements were collected. The specimens were then submitted to a CBCT in order to analyze the texture parameters. Results. Compared to the GC, in the GL there were changes in carbonate, phosphate and mainly amide groups. Regarding the GLF, the amide peaks were similar to the GL, but with differences in the phosphate and carbonate peaks. In the GF, there was an intermediate profile, with few changes. Meanwhile, in terms of texture, modified dentin showed significant difference among the groups in comparison to those not submitted to laser irradiation. Conclusions. Laser irradiation promoted significant changes in chemical composition and texture of the substrate. However, the new associated photoabsorber was not able to potentiate the action of the Nd:YAG laser on dentin.
  • Resumo IPEN-doc 30471
    Analysis of acid resistance of enamel treated with Nd:YAG laser and fluoride in different pHs
    2023 - CARAMEL-JUVINO, AMANDA; AVELINO, SABRINA G.; OLIVEIRA, YASMIN R.F.; ZEZELL, DENISE M.
    Background. High power lasers can be used in caries prevention to increase resistance of tooth structure to demineralization through changes in microstructure. Objectives. This study was designed to evaluate the preventive effect of treatment with the Nd:YAG laser and fluoride on dental caries by analyzing the acid resistance of treated enamel subjected to different pH conditions. Materials and methods. A total of 180 samples of human dental enamel were prepared, homogenized with surface microhardness and randomized into 12 groups (n = 15): negative control, positive control (fluoride only), Nd:YAG irradiation, and Nd:YAG + fluoride. Each treatment included 3 different groups for pH cycling, at pH = 5, pH = 4.5 and pH = 4. In the proposed treatment, topical application of acidulated phosphate fluoride (1.23%) was used followed by laser irradiation (Nd:YAG, l = 1,064 nm, energy density per pulse = 84 J/cm², repetition rate = 10 Hz, pulse width = 300 ms). Samples were analyzed using optical coherence tomography (OCT) and Fourier transform infrared spectroscopy (FTIR) in the attenuated total reflection (ATR) mode. The OCT is a non-contact imaging technique which generates cross-sectional images of tissue with high resolution, providing a profile of backscattered light intensity over tissue depth that can indicate the demineralization level. Intensities of infrared bands (ATR/FTIR) are proportional to the amount of components in the tissue, allowing to determine variations which occurred due to a specific treatment. Results. In FTIR, the areas under the collagen, phosphate, carbonate, amide I, and amide II bands were analyzed using the locally developed software – IR Hard Tissue®. There was an increase in the phosphate values in the Nd:YAG + fluoride group, with a statistical difference regarding pH = 4.5 (multiple comparison analysis of variance (ANOVA) + Dunnett, p > 0.05). There was a positive decrease in collagen in the Nd:YAG + fluoride groups, with a significant difference for the other groups at pH 4.5, and a significant difference for the other groups at pH 4, except for the isolated Nd:YAG group. There was no statistical difference for carbonate values. In the OCT analysis, a decrease in the attenuation coefficient was noticeable, indicating less demineralization. At pH = 5, there was a significant difference in the Nd:YAG + fluoride group for all treatments, except for the isolated Nd:YAG group. At pH = 4.5 and pH = 4, the only group with statistical difference from the others was the Nd:YAG + fluoride group (multiple comparison ANOVA + Dunnett, p > 0.05). Conclusions. The treatment with the Nd:YAG laser and fluoride is effective in increasing enamel acid resistance, being more beneficial than the use of fluoride alone, even in critical pH conditions for fluoride-treated enamel (pH = 4.5).
  • Resumo IPEN-doc 30470
    Effectiveness of non-ablative treatment for snoring and obstructive sleep apnea with two high-intensity pulsed lasers
    2023 - MENDES, VALERIA; AZEVEDO, LUCIANE H.; ZEZELL, DENISE M.
    Primary snoring and obstructive sleep apnea (OSA) represent different severity degrees of the same disorder, which affects one billion people worldwide. Increased cardiovascular risk, emergence of chronic diseases and use of medications result from disease worsening and represent a major challenge for health systems. A palatopharyngeal muscle tone dysregulation plays a significant role in this disorder. All therapeutic approaches have limitations. Speech therapy exercises show improvement in muscle tone, reducing snoring and OSA, positively signaling laser treatment, which can contribute to improvement of sleep breathing disorder (SBD). This study aims to evaluate the treatment of SDB with high-intensity non-ablative irradiation with 2 pulsed lasers: Nd:YAG laser (1064 nm) and Er:YAG laser (2940 nm), comparing results before and after the intervention. After obtaining the approval of research ethics committee, 30 volunteers from primary snoring to moderate OSA were treated in 3 sessions of laser irradiation, 14 days apart. Upper airway lumen was analyzed, according to modified Mallampati index by 3 independent, blinded and calibrated evaluators. Oxyhemoglobin desaturation index (ODI), severity of snoring and sleep quality were also evaluated. The observation of variability for each outcome allowed for the analysis of difference between the experimental periods in relation to baseline for each variable and the behavior of laser group in relation to control. Then, classification “Reduced” or “Didn’t Reduce” was assigned to the variation above, making it possible to apply the χ2 test corrected by Fisher, with a significance level of α = 5%. The main clinical result obtained is the expansion of upper airways lumen (control and laser group variation: (0.0 ±0.0); (–25.0 ±50.0) with p = 0.00060). Therefore, the improvement of ODI (19.6 ±67.6); (–18.1 ±88.2) with p = 0.018; snoring time (64.8 ±179.1); (–1.5 ±85.0) with p = 0.034; snoring peak amplitude (–8.3 ±12.3); (–12.4 ±15.8) with p = 0.029 were observed. Non-ablative laser treatment is effective in rehabilitation of patients with SBD. In the protocol used in this work, the procedure is performed without need of medication or anesthesia. The expansion of upper airways lumen by decreasing tissue compliance leads to improved sleep quality, snoring severity and daytime sleepiness (p = 0.00026, p = 0.02171 and p = 0.027, respectively), contributing to the improvement of observed health parameters.
  • Resumo IPEN-doc 30469
    Importance of heat generation and propagation on dental tissues due to high-intensity laser irradiation for safe clinical use
    2023 - ZEZELL, DENISE M.
    Erbium lasers are strongly absorbed by water and hydroxyapatite, which are the main components of hard tissues (enamel, dentin and bone). Consequently, these lasers can be efficiently used for cutting hard tissue, for cavity preparation, for caries removal, caries and erosion prevention, when laser irradiation should change chemically the structure of dental hard tissue in order to increase their resistance to demineralization. More recently, erbium lasers are being used for debonding ceramics. Only using proper irradiation conditions, minimally invasive procedures with low thermal or mechanic damages to the tissues can be achieved. For these applications, erbium lasers can increase the temperature up to 1200°C on dentin and enamel surface, and the thermal effects must be controlled to avoid thermal damages, such as carbonization and cracks that can weaken the irradiated tissue or even damage the pulp or periodontal tissue. Therefore, it is strongly required to know the thermal effects of laser irradiation on target tissues, which depend on the laser parameters and refrigeration methods. Studies regarding superficial thermal changes promoted by the Er,Cr:YSGG laser irradiation on enamel will be described, according to the experimental measurements performed by infrared thermography. Fast-response thermocouples were also used to determine the temperature increase inside the pulp chamber and at periodontal tissue during laser irradiation simulating a clinical protocol. These studies were useful for determining laser energy densities and time of irradiation. The characteristics of laser irradiation, such as wavelength, laser absorption and optical properties of enamel were strictly considered. These studies demonstrate the strong effects of a higher-absorbed laser wavelength on biological tissues and how the practitioners can avoid possible thermal damages due to laser irradiation. The knowledge of optical changes on biological tissues due to heat is also an important point to be considered for determining laser parameters in a future clinical practice.
  • Resumo IPEN-doc 30468
    Dental bleaching with violet LEDs based on scientific evidence
    2023 - WINDLIN, MATHEUS C.; BUENO, ISABELA; BRUGNERA, ANA P.; ZANIN, FATIMA; ZEZELL, DENISE M.; BRUGNERA JUNIOR, ALDO
    Dental bleaching has become increasingly popular in recent years, and violet LEDs have emerged as a promising tool for achieving optimal results. However, the success of this technique depends on the dentist’s knowledge and expertise. This study examines the current state of knowledge on dental bleaching with violet LEDs among dentists and correlates the impact of knowledge on the success of clinical practice. We included a literature review and case studies of patients who underwent dental bleaching with violet LEDs. Dentists with a strong knowledge base on this technique are more likely to achieve successful outcomes. Therefore, it is crucial for dentists to stay up to date with the latest research and advancements in dental bleaching with violet LEDs to improve their clinical practice and provide optimal care for their patients.
  • Resumo IPEN-doc 30431
    Non-ablative laser treatment for snoring and obstructive sleep apnea
    2024 - MENDES, V.; AZEVEDO, L.; ZEZELL, D.
    Introduction: By preventing the progression of sleep breathing disorder (SBD) , the risk of developing chronic diseases highly prevalent in society, such as hypertension and type 2 diabetes, is reduced. This study aimed to clinically evaluate the effect of non-ablative treatment with Nd:YAG (1064 nm) and Er:YAG lasers (2940 nm) in sleep breathing disorder (SBD), in a longitudinal, interventional and prospective study. Materials and Methods: After approval from the Research Ethics Committee (CEP FOUSP CAAE: 44068621.8.0000.0075) and clinical trial registration - WHO - Rebec UTN code: U1111-1284-3764, thirty volunteers, in the city of São Paulo, Brazil, with clinical status from snoring to moderate OSA, both sexes, 25 to 65 years old, BMI < 40kg/m2 were blinded and randomized in control and laser groups. Patients received three treatment sessions, 14 days apart. In the control group (12 volunteers), only a guide light was used without delivering laser energy. 18 volunteers of laser group were treated with non-ablative high-intensity irradiation with the association of Nd:YAG and Er:YAG lasers. Entire soft palate, uvula, palatoglossal and palatopharyngeal arches were punctually irradiated with four to five shoots per point and six scans in each line. Parameters were selected to deliver energy efficiently and safely in a five-step sequence wich enable tissue thermal sensitization, gradually. Outcome measures were performed before, after treatment and at three and six months follow up visits, including photographic record, type IV polysomnography and analysis of snoring noise. The main outcome of the study, analysis of the upper airway lumen variation according to the Modified Mallampati Index was performed independently and blinded and as well as the statical analysis. Oxyhemoglobin desaturation index (ODI), snoring time during sleep and peak amplitude of snoring noise were also analysed. Observation of the variability of each outcome allowed analysis of the differences between experimental periods compared to baseline for each variable and the behavior of the laser group compared to the control group. Fisher's corrected chi-square test with a significance level of α = 5% was applied. Results: The main clinical outcome is the expansion of the upper airway lumen, in all study periods analyzed after irradiation [variation between control and laser groups: (0.0 ± 0.0); (-25.0 ± 50.0) with p = 0.00060]. Therefore, improvement in ODI [variation between control and laser groups: (19.6 ± 67.6); (-18.1 ± 88.2) with p = 0.018]; improvement in snoring time (64.8 ± 179.1); (-1.5 ± 85.0) with p = 0.034 and in snoring noise peak amplitude (-8.3 ± 12.3); (-12.4 ± 15.8) with p = 0.029. No major adverse events or side effects were observed. Conclusion: Non-ablative laser treatment is effective in rehabilitation of patients with Sleep Breathing Disorder. In the protocol used in this study, the procedure is performed in outpatiente basis, without medication or anesthesia. Increasing the lumen of the upper airway by decreasing tissue flaccidity, leads to the improvement of oxyhemoglobin desaturation index (ODI), snoring time during sleep and peak amplitude of snoring noise.
  • Resumo IPEN-doc 30407
    Panorama dos exames de PET-CT - FDG-18F no câncer do colo do útero em uma instituição privada do Brasil
    2024 - PEDREIRA, YURI A.; PRADO, LEONARDO F.M. do; SILVA, MARCELO M. da; MENEZES, MARIO O. de; VIVIANI, DIONISIO N.; BOENO, BRUNO R. de O.; VIVIANI, CARLA L.S.
    Introdução/Justificativa: Existem mais de 200 tipos de HPV no mundo, sendo 14 deles cancerígenos. Destes, os tipos 16 e 18 são responsáveis por 70% dos cânceres de colo de útero e lesões pré-cancerosas. Também podem provocar câncer em vagina, ânus, vulva, pênis e orofaringe. Em 2020, foram diagnosticados 602 mil novos casos de câncer cervical em todo o mundo, com 342 mil mortes. No Brasil, a mortalidade pela doença ente 1980 e 2020 foi de 165.087.2 O exame de PET-CT com Fluorodesoxiglicose marcada com F-18 (PET-CT 18F-FDG) pode ser fundamental para elucidação diagnóstica, estadiamento e acompanhamento de pacientes nos diferentes estágios da doença, trazendo maior acurácia e a possibilidade de detecção e localização de metástases. Objetivos: No Brasil, os dados oficiais revelam que cerca de 35% dos casos de câncer de colo uterino ainda são diagnosticados nas fases III e IV, ou seja, em doença avançada, sendo que a partir da fase III existe disseminação linfonodal pélvica ou para-aórtica. Diante disso, o objetivo deste estudo foi a avaliação do panorama dos exames de PET-CT 18F-FDG realizados em uma instituição privada com a indicação de câncer de colo uterino e verificar se os dados coletados são condizentes com os dados encontrados na realidade brasileira. Materiais e Métodos: Este estudo foi realizado utilizando-se o banco de dados de uma instituição privada. Buscados exames de PET-CT 18F-FDG com a indicação de neoplasia de colo uterino no período de 01.01.2019 a 31.08.2023. Identificados 183 estudos, sendo 36 excluídos por duplicidade e/ou indicação incorreta, permanecendo, no final, 147 exames para análise. Resultados: Quando avaliados por indicação, a grande maioria dos exames incluídos neste estudo foram realizados para avaliação de resposta (56,5%), seguidos de estadiamento (18,4%), suspeita de recidiva (15,6%) e seguimento (9,5%). Avaliando apenas os exames de estadiamento, a grande maioria apresentava doença avançada e apenas 3,6% tiveram exame negativo. 10,7% das pacientes possuíam doença nos estágios iniciais (menor que IIIB), 10,7 no estágio IIIB, 17,9% no estágio IIIC1, 25% no IIIC2, sendo que 3,6% já apresentavam envolvimento de órgãos pélvicos (estágio IVA) e 28,6%, de órgãos a distância (estágio IVB). Quanto à suspeita de recidiva, este trabalho considerou 23 pacientes da amostra. Deste total, 78,3% dos exames foram positivos, 8,7% indeterminados e 13,0% negativos. Conclusão: Os dados encontrados no nosso serviço são semelhantes aos encontrados no Brasil. As regras vigentes no nosso país não propiciam o diagnóstico precoce do câncer de colo uterino, na contramão dos protocolos atualizados nos Estados Unidos e na Europa. Não há autorização prevista para estadiamento, nem acompanhamento pelo SUS ou pelo rol da ANS. Este cenário configura sério obstáculo à detecção da doença em um estágio mais inicial, o que possivelmente pouparia custos de tratamento na doença avançada, e aumentaria a sobrevida das pacientes, consolidando imediato benefício à saúde pública.
  • Resumo IPEN-doc 30406
    Avaliação da biodistribuição do radiofármaco 177Lu-PSMA I&T em animais com modelo tumoral
    2024 - BALIEIRO, LUIZA M.; FREIRE, MARIA R.V.B.; SANTOS, JOEL M.; ARAUJO, ELAINE B.
    Introdução/Justificativa: O antígeno de membrana específico da próstata (PSMA) é uma glicoproteína de transmembrana do tipo II que se mostra baixa ou não é expressa na próstata normal, mas é altamente expressa no câncer e apresenta-se ainda mais aumentada em pacientes metastáticos resistentes à castração, existindo um consenso no qual seu nível de expressão está ligado à malignidade da doença (MALIK, N. et al., 2015.; RUANGMA et al., 2019). Com isso, novos radiofármacos para o diagnóstico e terapia do câncer de próstata estão sendo descritos com base na descoberta de inibidores de PSMA, que se ligam especificamente ao grupo farmacofórico Glutamato-Ureia-Lisina (Di lorio, 2022). O radiofármaco baseado em PSMA-I&T, radiomarcado com lutécio-177 tem sido bastante estudado no mundo para essa terapia. Objetivos: O objetivo foi avaliar a captação do 177Lu-PSMA-I&T em camundongos com modelo tumoral por meio de estudos de biodistribuição invasiva (aprovado pelo CEUA-IPEN). Os estudos pré-clínicos representam importante passo para desenvolvimento e registro do produto, contribuindo para avaliação de segurança e eficácia. Materiais e Métodos: O radiomarcado 177Lu-PSMA-I&T (7,4 MBq/0,1 mL) foi inoculado em 20 camundongos com desenvolvimento de modelo pré-clínico de câncer de próstata utilizando células LNCaP, inoculadas no flanco superior esquerdo dos camundongos SCID. O estudo contemplou os tempos de 30, 60 min com e sem bloqueio e 2h após a administração do 177Lu-PSMA-I&T. Os animais foram eutanasiados para retirada do coração, pulmão, pâncreas, baço, estômago, fígado, rins, intestinos, cérebro, músculo, osso (fêmur) e cauda. Os órgãos foram pesados e contados em contador gama tipo poço (Cobra, Packard) para determinar a porcentagem da atividade administrada por grama (%AI/g). Os resultados foram analisados estatisticamente utilizando o programa GraphPad Prism. Resultados: O estudo de biodistribuição em camundongos SCID com tumor mostrou um rápido clareamento sanguíneo e excreção renal do 177Lu-PSMA-I&T. A maior captação do 177Lu-PSMA-I&T no tumor foi em 30 minutos, assim como na maioria dos órgãos que expressam PSMA, como os pulmões. Verificou-se uma correlação crescente na razão tumor:sangue em função do tempo, demonstrando a afinidade de ligação do radiofármaco. Analisando-se os grupos de 60 min, o bloqueio apresentou uma boa resposta, com diminuição da captação do 177Lu-PSMA-I&T nos órgãos que expressam PSMA e no tumor, sendo de 2,18 ± 0,27 %AI/g após 60 min sem bloqueio e 0,62 ± 0,17 %AI/g após 60 min com bloqueio. A captação nos rins também diminuiu drasticamente nos animais com bloqueio. Conclusão: Este estudo preliminar demonstra a especificidade do radiofármaco 177Lu-PSMA-I&T em modelo animal e representa importante pré-requisito para avaliação clínica, produção e o registro do produto no Brasil para uso disseminado na terapia de pacientes com câncer de próstata resistentes à castração. 1 - Malik, N. et al., Radiofluorination of PSMA-HBED via AI(18)F(2+) Chelation and Biological Evaluations In Vitro. Molecular Imaging and Biology, (2015). 2 - Ruangma A., et al., PSMA for Pet imaging of prostate cancer. The Bangkok medical Journal, (2019) 3 - Di lorio et al., Production and Quality Control of [177Lu]Lu-PSMA-I&T: Development of an Investigational Medicinal Product Dossier for Clinical Trials. (2022)
  • Resumo IPEN-doc 30286
    Performance evaluation of the incorporation of PET/CT procedures in the SUS
    2023 - PRATES, B.; POZZO, L.
    Aim/Introduction: High-complexity technologies, such as PET/ CT, should have their incorporation constantly analyzed and enhanced to support their consolidation. The evaluation of the performance of these equipment commits to the understanding of subjects such as the clinical application effectiveness, the usage of these devices in the patient’s real life, and the impact of this technology in the different regions where they are applied. Therefore, this work aimed to evaluate the performance incorporation PET/CT equipments and procedures by the Brazilian National Health System (SUS) according to admissibility, economic, innovation, and technical criteria, accordant to the Methodological Guideline for the Elaboration of Studies for the Evaluation of EMA (medical-assistance equipment). Furthermore, the demand for the application of this technology was also considered. Materials and Methods: The data collection methodology was based on an active search for information, such as the consultation of bibliographies and websites that presented data of interest, such as ANVISA, DATASUS, CNEN, and RHC. Results: Thirteen records of equipment from seven distinct manufacturers were identified within the validity period. Moreover, there are 110 registrations with at least one PET/CT equipment in the National Registration of Health Facilities (CNES) and 160 registrations of facilities authorized by the National Commission of Nuclear Energy (CNEN). Published by the National Health Fund (FNS), the value proposed for such equipment in 2022 is BRL 6,405,000.00. Regarding approved financing proposals, seven are registered and distributed in the records of five facilities. The applied taxes observed are IPI, PIS, and COFINS. Per procedure, according to the SUS table records, the amount paid was BRL 2,107.22, and the total amount paid since the incorporation of the technology is BRL 348,446,738.37. Conclusion: The development of the work led to the perception that, although there was some difficulty in obtaining some data that permeate the PET/CT technology, the incorporation of this technology took place in a satisfactory manner. There was divergence in results such as the number of devices. This fact was due to the way in which information was made available, as many data are self-declared by interested parties. Because it is the incorporation of a high-complexity technology in full use, few studies evaluating its performance were observed. Based on Consolidation Ordinance No. 1/2017 - which adopts the recommendation of one PET/CT unit per 1.5 million inhabitants, it was found that few Brazilian states have available the number of devices to meet the needs of demand.
  • Resumo IPEN-doc 29895
    Proteolytic activity of secreted proteases from pathogenic leptospires and effects on phagocytosis by murine macrophages
    2023 - AMAMURA, THAIS; COURROL, DANIELLA; BARBOSA, ANGELA; SILVA JÚNIOR, ILDEFONSO; SILVA, TIAGO da; MIDON, LEONARDO; HEINEMANN, MARCOS B.; CHAMBI, ROSA C.; MORGANTI, LIGIA; ISAAC, LOURDES
    Leptospirosis is a zoonosis caused by spirochete bacteria that belong to the genus Leptospira. This disease represents a serious public health problem, especially in developing countries with tropical and subtropical temperatures. Pathogenic leptospires escape from the Complement System, a property that permits them to survive in vitro when in contact with normal human serum (NHS). In a previous study carried out by our group, it was observed that culture supernatants from different pathogenic species of leptospires (SPL) contain proteases that cleave many Complement proteins, including the central molecule C3 and its fragments C3b and iC3b. Our hypothesis is that these proteases, could decrease the phagocytic clearance of leptospires. Using flow cytometry, we observed decreased amounts of CR3 and CR4 in murine peritoneal macrophages treated with SPL for 24 h. By confocal microscopy, we observed reduction in TLR2, CD11b and CD206 levels when these cells were treated with SPL and recombinant thermolysin for 24 h. Furthermore, opsonins such as C3b/iC3b deposited on the surface of pathogenic leptospires were observed to be completely degraded in the presence of SPL or recombinant thermolysin. Finally, we decided to investigate the phagocytosis of pathogenic leptospires by macrophages in the presence of these proteases. We observed an increase of phagocytosis of leptospires opsonized with normal mouse serum even when macrophages were treated with the proteases. However, when opsonized bacteria were also incubated with SPL, recombinant thermolysin and recombinant leptolysin., there was a decline in leptospires phagocytosis. This suggests that the proteolytic activity can affect phagocytosis by peritoneal macrophages mainly through the degradation of opsonins deposited in the membrane of leptospires. These observations lead us to suggest that proteases secreted by pathogenic leptospires could degrade opsonins present in normal serum or deposited in the bacterial membrane as well as cleave or inhibit macrophage surface molecules. Therefore, these proteases could interfere with the recognition and internalization by murine macrophages, favoring the spread of leptospires in the host.
  • Resumo IPEN-doc 29894
    Leptospira interrogans leptolysin displays proteolytic activity against complement proteins
    2023 - COURROL, DANIELLA; SILVA, CRISTIANE F. da; CHAMBI, ROSA C.; MORGANTI, LIGIA; ISAAC, LOURDES; PORTARO, FERNANDA; SILVA, RODRIGO R. da; BARBOSA, ANGELA
    Pathogenic Leptospira species are extremely efficient in disseminating in the host, a fact attributed to their ability to escape complement system activation, and to degrade extracellular matrix and other components of the human plasma. Recently, our group evaluated the proteolytic activity of secreted proteins by leptospires, and exoproteome analyzes of these bacteria allowed the identification of some proteases, including the metalloprotease pappalysin-1 domain protein, which we named leptolysin. In this work we produced and functionally characterized leptolysin from L. interrogans to expand our knowledge on this metalloprotease from Leptospira in the processes of invasion and immune evasion. According to in silico analyzes this protease belongs to the category of short pappalysins, also found in other bacteria. Leptolysin is present in all Leptospira species but is more conserved among pathogenic species of the P1 subclade. A preliminary biochemical characterization of its proteolytic activity was performed using FRET (Free Resonance Energy Transfer) peptides. The enzyme exhibited maximum activity at pH 8.0 and 37 C, was active in the presence of different salts and was strongly inhibited by EDTA and 1,10-phenanthroline. It showed a marked preference for arginine residues in the P1 position. The proteolytic activity of recombinant leptolysin on host molecules was also evaluated in vitro and in vivo. The metalloprotease was active against extracellular matrix proteins (proteoglycans and fibronectin), coagulation cascade molecules (fibrinogen and thrombin) and effector proteins of the human complement system (C2 to C9). A leptolysin knockout strain (Dlic13434) was produced and characterized. This strain showed lower survival in normal human serum (SHN) compared to the wild-type strain. However, in a model of epicutaneous infection in hamsters, no attenuation of virulence was observed with the knockout strain, although the bacterial load in the kidneys of these animals was lower than that observed in animals inoculated with the wild-type strain. Finally, data with sera from leptospirosis patients suggest that leptolysin is produced during natural infections by pathogenic leptospires. The characterization of toxins, their targets and mechanisms of action can help in the development of strategies to combat leptospirosis.
  • Resumo IPEN-doc 29811
    ICC INTERCORR WCO 2021
    2022 - PANOSSIAN, ZEHBOUR; COSTA, ISOLDA; ROSSI, JESUALDO L.
    Brazil, once again, organized one of the world’s most significant corrosion events, the ICC - INTERNATIONAL CORROSION CONGRESS. In 1978, the 7th edition of the congress was held by ABRACO, in Rio de Janeiro, under the direction of our Dr. Aldo Cordeiro Dutra, chairman of the Executive Committee. To intertwine two events, the 21st ICC was held together with the traditional INTERCORR, the most representative corrosion and corrosion prevention event held in Brazil, organized by ABRACO, in its 8th edition, which included the workshop “Corrosion and Green Energy”, an event of the World Corrosion Organization (WCO). Thus, the ICC INTERCORR WCO 2021 was arranged with this strong partnership.The institutions responsible for organizing the ICC INTERCORR WCO 2021 were: the Brazilian Corrosion Association (ABRACO), the International Corrosion Council (ICC), and the World Corrosion Organization (WCO). To overcome a new post-pandemic Covid-19 reality, the event occurred virtually from July 20th to 23rd, 2021.The ICC INTERCORR WCO 2021 has become a reference for developing the industrial sector, being an excellent forum for presenting new technologies, disseminating knowledge, prospecting for brands, business opportunities and expanding relationships. Its main objective was to encourage the exchange of knowledge between researchers, technicians, professionals, and companies, whether nationally or globally.The ICC INTERCORR WCO 2021 program included the presentation of 6 plenary conferences, 19 lectures, and more than 220 technical articles by renowned specialists from different countries such as Germany, India, Egypt, USA, Portugal, Australia, Italy, Sweden, Spain, Brazil, among others.Today´s moment highlights the importance of promoting such an event in the country, aiming to find solutions to contribute to the recovery that the industrial sector needs. Maintaining the integrity of assets and minimizing operating and maintenance costs are highly relevant concerns in our daily lives, directly impacting the productive sector.Therefore, on behalf of the Executive Committee, we would like to thank all participants and members of the local organizing committee and the scientific committee. We also sincerely thank the support team for collaborating before, during and after this highly successful event.
  • Resumo IPEN-doc 29703
    Latin America Optics and Photonics 2022
    2023 - GOMES, ANDERSON S.L.; SOUZA, EUNEZIO T. de; ZEZELL, DENISE M.
    The 2022 Latin America Optics and Photonics Conference (LAOP 2022), the major international conference sponsored byOptica in Latin America, returned to Recife, Pernambuco, Brazil, after its first edition in 2010.Held every two years since (except for 2020), LAOP has the explicit objective to promote Latin American excellence in optics and photonics research and support the regional community. In the 6th edition in 2022, it featured a comprehensive technical program with recognized experts in fields critical to Latin America, highly multidisciplinary, with themes frombiophotonics to2Dmaterials. The 191 attendees of LAOP2022 listened to five plenary speakers, 28 keynotes, 24 invited talks, and 128 presentations, including oral and posters
  • Resumo IPEN-doc 29727
    Projeto e construção de um sistema de aquecimento por micro-ondas de baixo custo para avaliação de susceptores
    2022 - BRANDAO, ULISSES; SPINACE, ESTEVAM V.; SEKO, MURILO H.; FERREIRA, WILLIAM de P.
    Este trabalho consistiu no projeto e construção de um forno de micro-ondas de 2,45 GHz, destinado à avaliação de susceptores a serem utilizados como catalisadores, em temperaturas de 400 a 1.100 ºC. Sua construção baseou-se em simulações feitas em computador, seguida de testes e modificações para sua funcionalização.