Lymphomas affecting the submandibular glands.

BACKGROUND: Lymphomas affecting the submandibular glands are very uncommon and few reports are currently available in the literature. Therefore, the aim of the current study is to describe the clinical and microscopic features of an original series of lymphomas affecting the submandibular glands. MATERIAL AND METHODS: The pathology files of two institutions were searched for lymphoma cases affecting the submandibular glands. The original hematoxylin and eosin, and immunohistochemical slides were revised by a pathologist for diagnosis confirmation following the revised 4th edition of the World Health Organization classification of tumours of haematopoietic and lymphoid tissues. Clinical data regarding age, sex, clinical manifestation, treatment, follow-up and status at last appointment were retrieved from the patients' medical charts. RESULTS: During the period investigated, 16 cases were included in the study. Females predominated (10:6) with a mean age of 57.8 years-old. Tumors usually presented as asymptomatic swellings. MALT lymphoma represented the most common subtype, followed by diffuse large B cell lymphoma and follicular lymphoma. Three patients died, one of them affected by plasmablastic lymphoma, one by DLBCL and one by MALT lymphoma. CONCLUSIONS: Low-grade B cell lymphomas predominate in the submandibular glands, but DLBCL and other subtypes may also be rarely diagnosed in this salivary gland.

Final Results of GERDA on the Two-Neutrino Double-ß Decay Half-Life of

We present the measurement of the two-neutrino double-ß decay rate of ^{76}Ge performed with the GERDA Phase II experiment. With a subset of the entire GERDA exposure, 11.8 kg yr, the half-life of the process has been determined: T_{1/2}^{2ν}=(2.022±0.018_{stat}±0.038_{syst})×10^{21} yr. This is the most precise determination of the ^{76}Ge two-neutrino double-ß decay half-life and one of the most precise measurements of a double-ß decay process. The relevant nuclear matrix element can be extracted: M_{eff}^{2ν}=(0.101±0.001).

Search for tri-nucleon decays of 76Ge in GERDA.

We search for tri-nucleon decays of 76Ge in the dataset from the GERmanium Detector Array (GERDA) experiment. Decays that populate excited levels of the daughter nucleus above the threshold for particle emission lead to disintegration and are not considered. The ppp-, ppn-, and pnn-decays lead to 73Cu, 73Zn, and 73Ga nuclei, respectively. These nuclei are unstable and eventually proceed by the beta decay of 73Ga to 73Ge (stable). We search for the 73Ga decay exploiting the fact that it dominantly populates the 66.7 keV 73mGa state with half-life of 0.5 s. The nnn-decays of 76Ge that proceed via 73mGe are also included in our analysis. We find no signal candidate and place a limit on the sum of the decay widths of the inclusive tri-nucleon decays that corresponds to a lower lifetime limit of 1.2×1026 yr  (90% credible interval). This result improves previous limits for tri-nucleon decays by one to three orders of magnitude.

Liquid argon light collection and veto modeling in GERDA Phase II.

The ability to detect liquid argon scintillation light from within a densely packed high-purity germanium detector array allowed the Gerda experiment to reach an exceptionally low background rate in the search for neutrinoless double beta decay of 76 Ge. Proper modeling of the light propagation throughout the experimental setup, from any origin in the liquid argon volume to its eventual detection by the novel light read-out system, provides insight into the rejection capability and is a necessary ingredient to obtain robust background predictions. In this paper, we present a model of the Gerda liquid argon veto, as obtained by Monte Carlo simulations and constrained by calibration data, and highlight its application for background decomposition.

Pulse shape analysis in Gerda Phase II.

The GERmanium Detector Array (Gerda) collaboration searched for neutrinoless double- ß decay in 76 Ge using isotopically enriched high purity germanium detectors at the Laboratori Nazionali del Gran Sasso of INFN. After Phase I (2011-2013), the experiment benefited from several upgrades, including an additional active veto based on LAr instrumentation and a significant increase of mass by point-contact germanium detectors that improved the half-life sensitivity of Phase II (2015-2019) by an order of magnitude. At the core of the background mitigation strategy, the analysis of the time profile of individual pulses provides a powerful topological discrimination of signal-like and background-like events. Data from regular 228 Th calibrations and physics data were both considered in the evaluation of the pulse shape discrimination performance. In this work, we describe the various methods applied to the data collected in Gerda Phase II corresponding to an exposure of 103.7 kg year. These methods suppress the background by a factor of about 5 in the region of interest around Q ß ß = 2039  keV, while preserving ( 81 ± 3 ) % of the signal. In addition, an exhaustive list of parameters is provided which were used in the final data analysis.

Cytotoxicity of root canal irrigating solutions and photodynamic therapy using curcumin photosensitizer.

BACKGROUND: Photodynamic therapy (PDT) has shown satisfactory antibacterial effects. However, little information regarding the cytotoxicity potential of PDT using curcumin as a photosensitizer (PS) on fibroblasts are found. The aim of this in vitro study was to evaluate the cytotoxicity of root canal irrigating solutions and photodynamic therapy with curcumin PS on the L-929 cell line. METHODS: Healthy mouse skin fibroblast cells were distributed into the following 7 experimental groups: G1 - culture medium DMEM (control group); G2 - 0.9% sodium chloride; G3 - 2.5% sodium hypochlorite (NaOCl); G4 - 5% NaOCl; G5 - PDT with curcumin PS at 500 mg/L + blue LED; G6 - PDT with curcumin PS at 750 mg/L + blue LED; and G7 - PDT with curcumin PS at 1000 mg/L + blue LED. All experimental groups which underwent PDT action were submitted to blue LED for 4 min, with a wavelength of 480 nm and energy fluency of 75 J/cm². The cultures were maintained under standard cell culture conditions (37°C, 100% humidity, 5% CO2). Cell viability analysis was performed using the colorimetric method to evaluate the periods of 6, 24, and 48 h. Data were subjected to the Kruskal-Wallis test, followed by the Dunn test to compare groups and Friedman test to compare periods (α = 0.05). RESULTS: When comparing the periods, no significant differences were observed for any of the experimental groups analyzed (p > 0.05), except for the NaOCl2.5 group that exhibited higher cell viability at 6 h compared to the period of 48 h (p = 0.0489). In the comparisons of the experimental groups, there were no statistically significant differences between the control group compared to all disinfection protocols, regardless of the period evaluated (p > 0.05), except for the PDT + C1000 group that showed lower cell viability (P < 0.05). CONCLUSIONS: PDT with curcumin at 1000 mg/L was cytotoxic on L-929 fibroblast cell culture. However, laser-activated curcumin at a concentration of 500 mg/L presented no influence on L-929 fibroblast cell viability in in vitro conditions.

Characterization of inverted coaxial 76 Ge detectors in GERDA for future double- ß decay experiments.

Neutrinoless double- ß decay of 76 Ge is searched for with germanium detectors where source and detector of the decay are identical. For the success of future experiments it is important to increase the mass of the detectors. We report here on the characterization and testing of five prototype detectors manufactured in inverted coaxial (IC) geometry from material enriched to 88% in 76 Ge. IC detectors combine the large mass of the traditional semi-coaxial Ge detectors with the superior resolution and pulse shape discrimination power of point contact detectors which exhibited so far much lower mass. Their performance has been found to be satisfactory both when operated in vacuum cryostat and bare in liquid argon within the Gerda setup. The measured resolutions at the Q-value for double- ß decay of 76 Ge ( Q ß ß  = 2039 keV) are about 2.1 keV full width at half maximum in vacuum cryostat. After 18 months of operation within the ultra-low background environment of the GERmanium Detector Array (Gerda) experiment and an accumulated exposure of 8.5 kg · year, the background index after analysis cuts is measured to be 4 . 9 - 3.4 + 7.3 × 10 - 4 counts / ( keV · kg · year ) around Q ß ß . This work confirms the feasibility of IC detectors for the next-generation experiment Legend.

Calibration of the Gerda experiment.

The GERmanium Detector Array (Gerda) collaboration searched for neutrinoless double- ß decay in 76 Ge with an array of about 40 high-purity isotopically-enriched germanium detectors. The experimental signature of the decay is a monoenergetic signal at Q ß ß = 2039.061 ( 7 )  keV in the measured summed energy spectrum of the two emitted electrons. Both the energy reconstruction and resolution of the germanium detectors are crucial to separate a potential signal from various backgrounds, such as neutrino-accompanied double- ß decays allowed by the Standard Model. The energy resolution and stability were determined and monitored as a function of time using data from regular 228 Th calibrations. In this work, we describe the calibration process and associated data analysis of the full Gerda dataset, tailored to preserve the excellent resolution of the individual germanium detectors when combining data over several years.

Nutritional and quality changes in piglet concentrate affected by the mix / [Mudanças nutricionais e de qualidade no concentrado de leitão afetadas pela mistura]

The aim of this study was to evaluate the reasons of quality deviation of a concentrate from a predefined standard. Five treatments were established: T1 - Control, standard concentrate formulation (SCF); T2 - PXMore5, SCF with more 5% vitamin-mineral premix (VMP); T3 - PXLess5, SCF with less 5% VMP. All three treatments used a 400kg batches in an INTECNIAL mixer; T4 - FeedMixer, SCF using a 4,000kg batch in an IMOTO mixer; T5 - PremixMixer, SCF using a 1,200kg batch in an MUYANG mixer. For each treatment, bags of 20 kg were stored in three storage places for four months. Water activity of concentrate was affected by temperature and air relative humidity in different storage places. Regarding the kind of mixer, the greatest variation in concentration of crude protein, mineral residue, copper, zinc, and selenium was observed in the PremixMixer. Adjustments are imperative in the handling and use procedures of this kind of mixer to meet the quality requirements required in the concentrate production. Analyzing the effect of the mineral-vitamin premix level, no difference could be defined with the evaluated parameters.(AU)

O objetivo deste estudo foi avaliar as razões do desvio de qualidade de um concentrado de um padrão predefinido. Foram estabelecidos cinco tratamentos: T1 - controle, concentrado com formulação padrão (CFP); T2 - PXMais5, CFP com 5% a mais de vitaminas e minerais da pré-mistura (PVM); T3 - PXMenos5, CFP com 5% a menos de PVM. Todos esses três tratamentos utilizaram lotes de 400kg em um misturador INTECNIAL; T4 - FeedMixer, CFP usando um lote de 4.000kg em um misturador IMOTO; T5 - PremixMixer, CFP usando um lote de 1.200kg em um misturador MUYANG. Para cada tratamento, sacos de 20kg foram armazenados em três ambientes distintos por quatro meses. A atividade de água do concentrado foi afetada pela temperatura e umidade relativa do ar em diferentes locais de armazenamento. Em relação ao tipo de misturador, a maior variação na concentração de proteína bruta, resíduo mineral, cobre, zinco e selênio foi devido ao PremixMixer. Ajustes são imperativos nos procedimentos de manuseio e uso desse tipo de misturador para atender aos requisitos de qualidade exigidos na produção de concentrado. Ao se analisar o efeito do nível da pré-mistura de vitaminas e minerais, nenhuma diferença pôde ser definida com os parâmetros avaliados.(AU)

Facial restoration after trauma - nasolabial in monkey bugio - Alouatta caraya (Humboldt, 1812) - first case report / [Restauração facial pós trauma nasolabial em macaco bugio - Alouatta caraya (Humboldt, 1812) - relato de caso]

In the last decades in the State of Mato Grosso do Sul - Brazil, the reduction in the preservation of areas due to the degradation of the biome and destruction of the natural environment has caused animals, mainly in the order of non-human primates, to come closer to towns and highways, increasing the number of accidents and in some cases, deaths. New surgical techniques have been developed that favor these species as explained in this report. The howler monkey patient was traumatized in the facial region damaging important vital structures such as facial muscle groups responsible for swallowing food, chewing, breathing, defense, and communication (vocalization and mimicry), in addition to the cartilaginous nasal structures. However, reconstructive facial surgical techniques, used on humans, showed satisfactory results from an anatomical, functional, and aesthetic point of view in howler monkey, with acceptance of the animal with a safe postoperative period for a full recovery of the primate patient.(AU)

Nas últimas décadas, no estado do Mato Grosso do Sul - Brasil, a redução de áreas preservadas pela degradação de biomas e pela destruição de habitat naturais tem favorecido a aproximação de animais - muitos desses, primatas não humanos - em cidades e rodovias, aumentando o número de acidentes e, em alguns casos, de mortes. Novas técnicas cirúrgicas têm sido desenvolvidas, favorecendo essas espécies, como reportado neste trabalho. O paciente macaco bugio foi traumatizado em região facial, envolvendo importantes estruturas vitais, como grupos musculares faciais responsáveis pela apreensão alimentar, mastigação, respiração, defesa e comunicação (vocalização e mímicas), além das estruturas cartilaginosas nasais. No entanto, técnicas cirúrgicas reconstrutivas em face aplicadas e descritas em humanos apresentaram resultados satisfatórios dos pontos de vista anatômico, fisiológico e visual nos macacos bugio, com aceitação deles diante do estresse, com pós-operatório seguro, resultando na reabilitação do paciente primata.(AU)

Leptin decreases apoptosis and promotes the activation of primordial follicles through the phosphatidylinositol-3-kinase/protein kinase B pathway in cultured ovine ovarian tissue.

This study evaluated the effects of leptin on primordial follicle survival and activation after in vitro culture of ovine ovarian tissue and if leptin acts through the phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt) pathway. Ovarian fragments were fixed for histology (fresh control) or cultured for 7 days in control medium (α-MEM+) alone or supplemented with leptin (1, 5, 10, 25 or 50 ng/ml). Follicle morphology, activation and apoptosis were analyzed. Next, the fragments were cultured in the medium that showed the best results in the absence or the presence of the PI3K inhibitor (LY294002), and immunohistostaining of p-Akt protein was assessed. After culture, the percentage of normal follicles decreased (P < 0.05) in all treatments compared with the fresh control. Moreover, control medium and 1 ng/ml leptin had similar (P > 0.05) percentages of normal follicles, which were significantly higher than those in other treatments. However, culture with 1 ng/ml leptin maintained apoptosis similarly (P > 0.05) to that of the fresh control and lower (P < 0.05) than that in α-MEM+. Leptin did not influence follicle activation (P > 0.05) compared with the control medium (α-MEM+). Culture in 1 ng/ml leptin with LY294002 decreased the normal follicles and increased apoptosis, inhibited follicle activation (P < 0.05), and reduced p-Akt immunostaining, compared with the medium containing 1 ng/ml leptin without PI3K inhibitor. In conclusion, leptin at 1 ng/ml reduces apoptosis and promotes the activation of primordial follicles compared with the fresh control after in vitro culture of ovine ovarian tissue possibly through the PI3K/Akt pathway.

Inflammatory profile of apical periodontitis associated with liver fibrosis in rats: histological and immunohistochemical analysis.

AIM: To investigate the effects of liver fibrosis (LF) on the pro-inflammatory mediators and periapical bone resorption of apical periodontitis (AP) in rats. METHODOLOGY: Forty male Wistar rats were distributed into four groups: C - control, AP - rats with AP, LF - rats with LF, AP + LF - rats with AP and LF. LF was induced by carbon tetrachloride administration for 8 weeks and surgical bile duct ligation for 4 weeks; AP was induced in the teeth of rats by dental pulp exposure to the oral environment for 30 days. Jaws and livers were removed after euthanasia. Haematoxylin and Eosin (H&E) and Picrosirius Red (PSR) staining were used to confirm fibrosis in the livers. The jaws were analysed using H&E staining, immunohistochemical assays of interleukin (IL)-1ß, IL-6 and tumour necrosis factor-alpha (TNF-α). Student's t-test and Mann-Whitney's U-test were used for statistical analysis (P < 0.05). RESULTS: Inflammatory infiltrate was moderate in the AP group and severe in the AP + LF group (P < 0.05). Periapical bone resorption was significantly larger in the AP + LF group compared with the AP group (P < 0.05). IL-1ß, IL-6 and TNF-α levels were significantly higher in AP + LF group when compared to the AP group (P < 0.05). CONCLUSION: More intense inflammatory infiltrate, greater amounts of pro-inflammatory cytokines and increased periapical bone resorption were observed in the presence of liver fibrosis in rats with exposed pulps.

Use of an Integrated Geochemical and Ecotoxicological Approach to Evaluate Sediment Metal Contamination in Three Protected Estuarine Areas Along the Coast of São Paulo State, Brazil.

We compared sediment quality in estuaries at three locations along the coast of São Paulo State, Brazil, using geochemical analyses and whole sediment toxicity tests, during the southern summer and winter of 2013. Each locality is afforded a distinct degree of legal protection, and exhibits a different level of metal pollution: overall, Rio Diana (RD, the most polluted, a Permanent Protection Area) > Rio Itapanhaú (RI, intermediate contamination, an Environmental Protection Area) > Rio Picinguaba (RP, pristine, a State Park). Chronic sediment toxicity tests evaluated reproductive rates of the copepod Nitokra sp. RI sediments showed the highest metal concentrations and toxicity in both seasons. Metal concentrations at RD were low but toxic in summer. RP sediments were not contaminated, suggesting effective legal protection from pollution at this locality. RI and RD, although provided some legal protection, showed clear signs of environmental degradation, emphasizing the need for more effective pollution control.

Nanoemulsions containing plant oils: How do they influence hair treatment?

OBJECTIVE: Cosmetic and dermatological products, mainly the hair treatments, are projected to have remarkable growing in coming years. Nanotechnology, specifically nanoemulsions, has potential to be used in several hair products, owing to their beneficial properties. Concurrently, plant-derived cosmetics have become more popular over the years to consumers who prefer a safer, natural and sustainable approach. There is a lack of studies combining plant oils and nanotechnology for haircare formulations. In this work, different plant oil-loaded nanoemulsions were prepared to investigate the influence of their particle size, zeta potential and composition on hair treatment efficacy. METHODS: Coconut, olive and Abyssinian oils, alone or in combination, were loaded into nanoemulsions by high-pressure homogenization method (HPH). The mean particle size, polydispersity index and zeta potential were measured by the dynamic light scattering (DLS) method, and a stability test was performed for five months. A sensorial screening evaluation performed by the analyst and the combing test using Dia-Stron® instrumentation were applied on hair tresses treated by these nanoemulsions. RESULTS: The use of different plant oils for nanoemulsion resulted in distinct final particle sizes and zeta potential. However, results suggested no significant difference between them in hair tresses combing efficacy compared by Dia-Stron® instrument testing. Moreover, the plant-loaded nanoemulsions with increased concentration of cationic surfactant indicated a 50% reduction in combing force using this device when compared to control, in addition to better sensory results by screening test compared to other nanoemulsions and control. CONCLUSION: The composition of plant oils, particle size or zeta potential of the prepared nanoemulsions does not seem to significantly influence hair performance. Thus, we suggest that finding the right balance between cationic surfactant and plant oils may be the most appropriate path to develop effective nanoemulsions in hair treatment.

OBJECTIF: Les produits cosmétiques et dermatologiques, principalement les traitements capillaires, devraient connaître une croissance remarquable dans les années à venir. La nanotechnologie, en particulier les nanoémulsions, a le potentiel d'être utilisée dans plusieurs produits capillaires, en raison de leurs propriétés bénéfiques. Parallèlement, les cosmétiques d'origine végétale sont devenus plus populaires au fil des ans auprès des consommateurs qui préfèrent une approche plus sûre, naturelle et durable. Il existe un manque d'études combinant les huiles végétales et la nanotechnologie pour les formulations de traitement capillaire. Dans ce travail, différentes nanoémulsions contenant de l'huile végétale ont été préparées pour étudier l'influence de leur taille de particule, de leur potentiel zêta et de leur composition sur l'efficacité du traitement capillaire. MÉTHODES: Les huiles de noix de coco, d'olive et d'Abyssinie, seules ou en combinaison, ont été chargées dans des nanoémulsions par méthode d'homogénéisation à haute pression (HPH). La taille moyenne des particules, l'indice de polydispersité et le potentiel zêta ont été mesurés par la méthode de diffusion dynamique de la lumière (DLS), et un test de stabilité a été effectué pendant cinq mois. Une évaluation sensoriel réalisée par l'analyste et le test de peignage à l'aide de l'instrumentation Dia - Stron® ont été appliqués sur les cheveux traités par ces nanoémulsions. RÉSULTATS: L'utilisation de différentes huiles végétales pour la nanoémulsion a donné des tailles de particules finales et un potentiel zêta distinct. Cependant, les résultats n'ont suggéré aucune différence significative entre eux dans l'efficacité du peignage des cheveux par rapport aux tests d'instruments Dia-Stron®. De plus, la nanoémulsion chargée avec une concentration plus élevée de tensioactif cationique a indiqué une réduction de 50% de la force de peignage en utilisant ce dispositif par rapport au contrôle, et, le screening a montré de meilleurs résultats sensoriels par rapport aux autres nanoémulsions et contrôle. CONCLUSION: La composition des huiles végétales, la taille des particules ou le potentiel zêta des nanoémulsions préparées ne semblent pas influencer significativement les performances capillaires. Ainsi, nous suggérons que trouver le bon équilibre entre un tensioactif cationique et des huiles végétales peut être la voie la plus appropriée pour développer des nanoémulsions efficaces dans le traitement des cheveux.

Effects of chelating calcium in cryopreservation extender on frozen-thawed dog semen / [Efeitos da quelação de cálcio no meio de criopreservação no sêmen descongelado de cão]

We evaluated the effect of reducing free calcium in the cryopreservation medium, using the calcium chelator ethylene diamine tetracetic acid (EDTA) at 0.3% and 0.5% concentrations. Three male mixed breed dogs were subjected to semen collection by digital manipulation (n=16). Each ejaculate was divided in three aliquots, and each one was diluted in TRIS-glucose-egg yolk extender with 6% glycerol and 0.5% Equex STM Paste® (TGE, control); and added with 0.3% EDTA (EDTA 0.3) or 0.5% EDTA (EDTA 0.5). Calcium concentration reduced in EDTA 0.3 and all the calcium ions were chelated in EDTA 0.5. The EDTA addition did not affect sperm morphology or plasma membrane integrity; however, by removing all free calcium (EDTA 0.5), the sperm motility reduced (64.7% in TGE and 45% in EDTA 0.5; p<0.05). Acrosome integrity and sperm binding ability were not improved by calcium chelation. The failure to prevent the premature AR may explain why sperm longevity was not affected by calcium removal. Thus, the partial or complete calcium removal, through EDTA addition, is not able to prevent acrosomal damage or premature acrosomal reaction, and therefore does not improve the dog sperm binding ability.(AU)

Avaliou-se o efeito da redução do cálcio livre no meio de congelamento, usando-se o quelante de cálcio etilenodiaminotetracético (EDTA) a 0,3% e 0,5%. Três cães machos sem raça definida foram submetidos à coleta de sêmen por manipulação digital (n=16). Cada ejaculado foi diluído em diluidor controle com TRIS-glicose - gema de ovo (TGE, controle), ou em diluidor TGE enriquecido com 0,3% (EDTA 0,3) ou 0,5% de EDTA (EDTA 0,5). A concentração de cálcio reduziu no meio EDTA 0,3, e todos os íons de cálcio foram quelados no meio EDTA 0,5. A adição do EDTA e a consequente quelação do cálcio não afetaram a morfologia espermática ou a integridade da membrana plasmática, no entanto, ao remover todo o cálcio do meio (EDTA 0,5), a motilidade espermática se reduziu (64,7% no TGE e 45% no EDTA 0,5; P<0,05). A integridade do acrossoma e a capacidade de ligação do espermatozoide não melhoraram com a quelação do cálcio. Apesar da influência da concentração de cálcio sobre a motilidade espermática após o descongelamento, a falha em prever a reação acrossomal prematura pode explicar por que a longevidade espermática não foi afetada pela remoção do cálcio no meio. Dessa forma, a remoção parcial ou total do cálcio, por meio da adição de EDTA, não é capaz de prevenir o dano no acrossoma ou a reação acrossomal prematura e, portanto, não aumenta a capacidade do espermatozoide de se ligar ao oócito.(AU)

Influence of photodynamic therapy on bond strength and adhesive interface morphology of MTA based root canal sealer to different thirds of intraradicular dentin.

BACKGROUND: Photodynamic therapy (PDT) is used as an adjunct to endodontic treatment to enhance microbial reduction in the root canal system. However, studies evaluating the impact of PDT on the bond strength of the canal sealer to intraradicular dentin are scarce. Thus, this in vitro study aimed to evaluate the influence of photodynamic therapy with methylene blue (MB) photosensitizer (PS) on the bond strength and morphology of the interface between mineral trioxide aggregate (MTA) based endodontic sealer and different thirds of intraradicular dentin. METHODS: Fifty-five bovine incisors were used to simulate experimental endodontic treatments. Biomechanical instrumentation was performed in all root canals and teeth were divided into 5 groups (n = 11): deionized water (control), methylene blue 50 mg/L (MB50WL), methylene blue 100 mg/L (MB100WL), methylene blue 50 mg/L + red laser (MB50L), and methylene blue 100 mg/L + red laser (MB100L). The push-out bond strength of canal sealer to intraradicular dentin was measured using a universal testing machine (n = 8). Representative scanning electron microscopy images were obtained to qualify the fracture patterns. Images of the adhesive interface morphology were obtained using confocal laser scanning microscopy (n = 3). The Kruskal-Wallis test was used to compare data on bond strength between groups, and the Friedman test between thirds (α = 0.05). RESULTS: When comparing root thirds for the MB group with the higher concentration activated by red laser, higher bond strength values was found for the apical third than for the middle third (P = 0.0302). MB in different concentrations, activated by red laser or not, had no influence on the bond strength of distinct thirds of the intraradicular dentin (P > 0.05). As for the adhesive interface morphology, the MB100L group showed a lower qualitatively sealer penetration into the intraradicular dentin. CONCLUSIONS: PDT with MB PS at 50 mg/L had no negative impact on the bond strength of MTA Fillapex canal sealer to intraradicular dentin, being a suitable antisepsis protocol for endodontic treatments.