Development and evaluation of the in vitro schistosomicidal activity of solid dispersions based on 2-(-5-bromo-1-H-indole-3-yl-methylene)-N-(naphthalene-1-ylhydrazine-carbothiamide.

Among all the neglected diseases, schistosomiasis is considered the second most important parasitic infection after malaria. Praziquantel is the most widely used drug for this disease, but its exclusive use may result in the development of drug-resistant schistosomiasis. To increase the control of the disease, new drugs have been developed as alternative treatments, among them 2-(-5-bromo-1-h-indole-3-yl-methylene)-N-(naphthalene-1-ylhydrazine-carbothiamide (LQIT/LT-50), which showed promising schistosomicidal activity in nonclinical studies. However, LQIT/LT-50 presents low solubility in water, resulting in reduced bioavailability. To overcome this solubility problem, the present study aimed to develop LQIT/LT-50 solid dispersions for the treatment of schistosomiasis. Solid dispersions were prepared through the solvent method using Soluplus©, polyethylene glycol (PEG) or polyvinylpyrrolidone (PVP K-30) as hydrophilic carriers. The formulations with the best results in the compatibility tests, aqueous solubility and preliminary stability studies have undergone solubility tests and physicochemical characterizations by Fourier-transform infrared spectroscopy (FTIR), x-ray diffractometry (XRD), exploratory differential calorimetry (DSC), thermogravimetry (TG) and Raman spectroscopy. Finally, the schistosomicidal activity was evaluated in vitro. The phycochemical analyzes showed that when using PVP K-30, there was an interaction between the PVP K-30 and LQIT/LT-50, proving the successful development of the solid dispersion. Furthermore, an increase in the solubility of the new system was observed (LQIT/LT-50:PVP K-30) in addition to the improvement in the in vitro shistosomidal activity at 1:4 (w/w) molar ratio (i.e., 20% drug loading) when compared to LQIT/LT-50 alone. The development of the LQIT/LT-50:PVP K-30 1:4 solid dispersion is encouraging for the future development of new pharmaceutical solid formulations, aiming the schistosomicidal treatment.

Effects of the probiotic Bacillus cereus GM on experimental schistosomiasis mansoni.

Probiotics contribute to the integrity of the intestinal mucosa and preventing dysbiosis caused by opportunistic pathogens, such as intestinal helminths. Bacillus cereus GM obtained from Biovicerin® was cultured to obtain spores for in vivo evaluation on experimental schistosomiasis. The assay was performed for 90 days, where all animals were infected with 50 cercariae of Schistosoma mansoni on the 15th day. Three experimental groups were formed, as follows: G1-saline solution from the 1st until the 90th day; G2-B. cereus GM (105 spores in 300 µL of sterile saline) from the 1st until the 90th day; and G3-B. cereus GM 35th day (onset of oviposition) until the 90th day. G2 showed a significant reduction of 43.4% of total worms, 48.8% of female worms and 42.5% of eggs in the liver tissue. In G3, the reduction was 25.2%, 29.1%, and 44% of the total number of worms, female worms, and eggs in the liver tissue, respectively. G2 and G3 showed a 25% (p < 0.001) and 22% (p < 0.001) reduction in AST levels, respectively, but ALT levels did not change. ALP levels were reduced by 23% (p < 0.001) in the G2 group, but not in the G3. The average volume of granulomas reduced (p < 0.0001) 65.2% and 46.3% in the liver tissue and 83.0% and 53.2% in the intestine, respectively, in groups G2 and G3. Th1 profile cytokine (IFN-γ, TNF-α, and IL-6) and IL-17 were significantly increased (p < 0.001) stimulated with B. cereus GM in groups G2 and G3. IL-4 showed significant values when the stimulus was mediated by ConA. By modulating the immune response, B. cereus GM reduced the burden of worms, improved some markers of liver function, and reduced the granulomatous inflammatory reaction in mice infected with S. mansoni, especially when administered before infection.

A collective autoethnography of coproduction in mental health research by academic researchers and young people in Brazil.

INTRODUCTION: Coproduction of mental health research and interventions involving researchers and young people is increasingly common. However, this model raises challenges, related, for instance, to communication, power and control. This paper narrates-from a collective first-person perspective-the lived experience of coproduction of a digital intervention by institutional researchers and young citizen researchers in Brazil. METHOD: This study employed a collaborative autoethnographic methodology, utilising autobiographical data such as meeting recordings, individual notes and collective guided reflections on the coproduction process. Our analysis focused on challenges and solutions that arose during the process. RESULTS: Throughout the project, we created formal and informal mechanisms for accountability, transparency and fair inclusion of multiple voices. We engaged in mutual capacity-building, invested in building interpersonal knowledge, and implemented practices to reduce overload and promote equitable participation. Through ongoing reflection and readjustment in response to challenges, we progressively embraced more democratic and egalitarian values. The collective care invested in the process fostered synergy, trust, and intergroup friendship. CONCLUSION: Our experience points to the value of creating a space for multiple research identities: the citizen young person and the institutional researcher, both of whom critically reflect on their roles in the research process. Our focus on coproduced care calls into question participation metaphors that represent the process via a single axis-young people-who linearly progress from minimal participation to full autonomy. Instead, our analysis highlights the importance of a social and caring bond that supports the radical co-production of innovative health solutions in contexts of vulnerability.

Potential of pharmaceutical formulation based on Morinda citrifolia extract for the treatment of schistosomiasis.

Schistosomiasis is a parasitic disease that can be asymptomatic, but it can progress and cause serious damage, such as hospitalization and death. This work aimed to characterize and carry out the in vivo pharmacological test of the dry extract of Morinda citrifolia and obtain a pharmaceutical dosage form based on this extract for the treatment of schistosomiasis. The aqueous extract was characterized based on the evaluation of pH, dry residue and density. The aqueous extract was dried through the freeze-drying process. The obtained dry extract was characterized through phytochemical screening, rheological analysis, acute toxicity and in vivo pharmacology. Additionally, the pre-formulation development of a pharmaceutical dosage form was pursued with the dry extract. Through the HPLC chromatogram, characteristic rutin peaks were identified. The rheological behavior of the dry extract did not show good characteristics. Acute toxicity, at a dose of 2000 mg/kg, showed excitatory activity in the central and autonomous nervous system. The in vivo pharmacological test of the dry extract showed that, at a dose of 400 mg/kg, it was possible to reduce 67.5% of the total adult worms, 66% of female worms and 60% of the number of eggs. The pharmaceutical dosage form obtained was an oral solution that was clear, transparent, without the presence of lumps and precipitates, having a density of 1.1276 g mL-1 and pH of 5.92. The results obtained will provide parameters for the production of suitable pharmaceutical formulations, as well as for the quality control of products based on M. citrifolia, with promising schistosomicidal activity.

Expressões de homofobia e conflito intergrupal entre fãs de league of legends / Expressions of homophobia and intergroup conflict between league of legends fans / Expresiones de homofobia y conflicto intergrupal entre aficionados de league of legends

Os jogos digitais são considerados um ambiente de privilégio masculino que exalta o padrão heteronormativo de masculinidade. A partir da Teoria das Representações Sociais, buscamos identificar as diferentes formas de expressão e ancoragens da homofobia a partir de princípios organizadores, nos discursos dos fãs do jogo League of Legends (LoL) na rede social Facebook. Foram selecionados 470 comentários publicados em 2017, os quais foram analisados com apoio do Iramuteq (software de análise lexicométrica) por meio de uma classificação hierárquica descendente, resultando em quatro classes: "Debate sobre a sexualidade dos campeões" (14,9%), "Representatividade no LoL" (29,8%), "Confronto entre as histórias de Varus" (39%), e "Estratégia empresarial" (16,2%). Os resultados evidenciam a existência de um conflito intergrupal, mediado pelo processo de ameaça simbólica: enquanto alguns comentários, realizados majoritariamente por homens heterossexuais, se utilizam do preconceito sutil para perpetuar a manutenção da heteronormatividade, outros comentários reforçam a importância da representação da diversidade nos jogos digitais.(AU)

Digital games are considered an environment of male privilege that promotes heteronormative standard of masculinity. Based on the Theory of Social Representations, we seek to identify, based on organizing principles, the forms of expression and anchorages processes related to homophobia within the speeches of the fans of the game League of Legends (LoL), on Facebook. A total of 470 comments published in 2017 were selected to be then analyzed with support from IRAMUTEQ software (lexicometric analysis software), which resulted in four classes: "Debate on the sexuality of champions" (14.9%), "Representativeness in LoL" (29.8%), "Confrontation between the stories of Varus" (39%), and "Business strategy" (16.2%). The results show intergroup conflict that is mediated by the process of symbolic threat: some comments, which are mostly from heterosexual men, carry aspects of covert prejudice to perpetuate the maintenance of heteronormative standards, whereas other comments reinforce the importance of representing diversity in digital games.(AU)

Los juegos digitales son un entorno de privilegio masculino que enaltece el estándar heteronormativo de la masculinidad. Con base en la Teoría de las Representaciones Sociales, buscamos identificar las formas de expresión y anclaje de la homofobia a partir de principios organizativos en los discursos de aficionados del juego League of Legends (LoL) en la red social Facebook. Se seleccionaron 470 comentarios publicados en 2017, que pasaron por el análisis en IRAMUTEQ (software de análisis lexicométrico) mediante una clasificación jerárquica descendiente la cual dio como resultado cuatro clases: "Debate sobre la sexualidad de campeones" (14,9%), "Representatividad en LoL" (29,8%), "Confrontación entre las historias de Varus" (39%) y "Estrategia comercial" (16,2%). Los resultados muestran un conflicto intergrupal, mediado por la amenaza simbólica; mientras que algunos comentarios, hechos en su mayoría por hombres heterosexuales, utilizan prejuicios sutiles para perpetuar el mantenimiento de la heteronormatividad, otros comentarios refuerzan la importancia de representar la diversidad en los juegos digitales.(AU)

Exploratory analysis of the microbial community profile of the municipal solid waste leachate treatment system: A case study.

Studies on the degradation dynamics of landfill leachate indicate that the microbial community profile is a valuable and sensitive tool for landfill monitoring programs. Although knowledge about the microbial community can improve the efficiency of leachate treatment systems, little is known about the microbial profile changes that occur throughout the leachate attenuation process. In the present work, an exploratory analysis of the microbial community profile of the MSW leachate treatment system in the municipality of Osório (Brazil) was conducted. In this way, a comprehensive analysis of chemical parameters, isotopic signature and microbial profile data were applied to monitor the changes in the structure of the microbial community throughout the leachate attenuation process and to describe the relationship between the microbial community structure and the attenuation of chemical and isotopic parameters. From data analysis, it was possible to assess the microbial community structure and relate it to the attenuation of chemical and isotopic parameters. Based on massive parallel 16S rRNA gene sequencing, it was possible to observe that each leachate treatment unit has a specific microbial consortium, reflecting the adaptation of different microorganisms to changes in leachate characteristics throughout treatment. From our results, we concluded that the structure of the microbial community is sensitive to the leachate composition and can be applied to study the municipal solid waste management system.

Repercussões vivenciadas por profissionais de saúde atendidos com Práticas Integrativas e Complementares durante a pandemia / Repercussions experienced by health professionals working with Integrative and Complementary Practices during the pandemic

RESUMO Objetivo analisar as repercussões vivenciadas por profissionais de saúde que foram atendidos com a utilização de práticas integrativas e complementares durante a pandemia da COVID-19. Métodos estudo qualitativo cujos dados foram coletados por meio de entrevistas, as quais foram transcritas e submetidas a análise de conteúdo temática. Resultados participaram 12 profissionais de saúde do sexo feminino que apontaram a importância da inclusão das práticas integrativas e complementares no fortalecimento do bem-estar dos profissionais de saúde no Sistema Único de Saúde e a relevância da oferta destes atendimentos no cenário pandêmico, pois as ajudou no enfrentamento do estresse, insônia, cansaço mental e ansiedade. Emergiram duas categorias: Sensação de valorização, acolhimento, reconhecimento e cuidado e Repercussões na saúde emocional e física das trabalhadoras. Conclusão os dados demonstraram as repercussões positivas das Práticas Integrativas e Complementares desenvolvidas pelos profissionais de saúde, demonstrando a potencialidade dessas práticas na promoção da saúde mental. Contribuições para a prática a implementação de ações com o uso das Práticas Integrativas e Complementares pelos gestores se constitui em forma de cuidado pelo profissional de saúde no Sistema Único de Saúde, pois estas resultam em qualidade de vida, promoção e restabelecimento da saúde física e mental dos indivíduos atendidos.

ABSTRACT Objective to analyze the repercussions experienced by health professionals who were assisted with the use of integrative and complementary practices during the pandemic of COVID-19. Methods qualitative study whose data were collected through interviews, which were transcribed and submitted to thematic content analysis. Results 12 female health professionals participated and pointed out the importance of the inclusion of integrative and complementary practices in strengthening the well-being of health professionals in the Unified Health System and the relevance of offering these services in the pandemic scenario, as it helped them face stress, insomnia, mental fatigue, and anxiety. Two categories emerged: Sensation of valorization, welcoming, recognition and care, and Repercussions on the emotional and physical health of the workers. Conclusion the data showed the positive repercussions of Integrative and Complementary Practices developed by health professionals, demonstrating the potentiality of these practices in promoting mental health. Contributions to practice the implementation of actions with the use of Integrative and Complementary Practices by managers constitutes a form of care by health professionals in the Unified Health System, as these result in quality of life, promotion, and restoration of physical and mental health of the individuals assisted.

Mechanical analysis of prosthetic bars and dental implants in 3 and 4 implant-supported overdenture protocols using finite element analysis.

In some clinical situations, the installation of four or more dental implants may be infeasible. Therefore, the installation of protocol-type prostheses with only three implants may be necessary. The mechanical failures can hinder the success of the rehabilitation treatment. OBJECTIVE: To evaluate and compare the mechanical stress of the metallic prosthetic bar when installed over protocol-type prostheses of three and four implants, and to evaluate the stress on the dental implants. METHODOLOGY: Two three-dimensional human jaw models were created. In one model, four dental implants (P4) were designed and in the other model three dental implants (P3) were designed. In both models, according to the arrangement of the dental implants, prosthetic bars were designed. In a finite element analysis software, compressive forces were applied to the ends of both prosthetic bars, simulating the force application during mastication. Tension and stress dissipation were analyzed on the prosthetic bar and dental implants. RESULTS: Both P4 and P3 protocol-type prostheses supported the force efficiently without breaking the bar or the implants. Force dissipation along the bar was more homogeneous in the P3 prosthetic bar than in P4. In addition, P3 implants received a higher concentration of stress in relation to P4 implants. CONCLUSIONS: Prosthetic bars and dental implants withstand the stress of load application in both four and three implant protocol-type prostheses. Three-implants protocol showed more satisfactory force dissipation than the four-implant protocol.

Assessing raw materials as potential adsorbents to remove acidic compounds from Brazilian crude oils by ESI (-) FT-ICR MS.

The presence of acidic compounds as naphthenic acids in crude oil causes several problems for the petroleum industry, including corrosion in both upstream and downstream production processes. Based on this scenario, the main objective of this work was to investigate the removal of the acidic compound from two Brazilian heavy oils by adsorption processes using six potential adsorbents: powdered shale, activated carbon, bentonite, silica gel, powdered sandstone and powdered wood. These raw materials were previously characterized by conventional and surface analysis techniques, which show that they offer a good surface area and thermal stability. To evaluate the removal efficiency at the molecular level, the crude oil samples and the filtered oils were analyzed by negative electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry [ESI (-) FTICR MS]. The O2 class, which is related to the relatively high acidity of the samples, was the most abundant in both crude oil samples, moreover, this class was more retained by adsorbents. Silica gel, activated carbon and bentonite were the best adsorbents of acidic compounds from the tested oils, in agreement with their markedly higher surface area and porous volume. Additionally, a chromatographic analysis was performed and showed no changes in the oil profile.

Currículo oculto, educação médica e profissionalismo: uma revisão integrativa / Hidden curriculum, medical education, and professionalism: an integrative review / Currículo oculto, educación médica y profesionalismo: una revisión integradora

O currículo oculto resulta das relações interpessoais vividas academicamente, extrapolando o currículo formal, podendo ser um facilitador e também um empecilho ao aprendizado. Essa revisão objetiva compreender a abordagem da temática na educação médica e sua relação com o profissionalismo. A revisão integrativa nos permitiu observar uma sobrecarga cognitiva e emocional do(a)s estudantes causada pelo currículo oculto. Todavia, constatamos como a educação médica tem trabalhado com a finalidade de reduzir esses prejuízos. Nesse sentido, é importante problematizar os modelos hegemônicos que influenciam valores, interesses, discursos, saberes e práticas ao longo da formação. Para isso, é fundamental o debate em torno de conceitos/ações como identidade, diversidade, inclusão, hegemonia, ideologia, poder e cultura, que pode ocorrer de forma longitudinal e integrada em unidades curriculares relacionadas às humanidades.(AU)

Hidden curriculum results from interpersonal relations experienced in academia and go beyond the formal curriculum, being both a facilitator and an obstacle to learning. This analysis aims at understanding the thematic approach of medical education and its relationship with professionalism. Through an integrative review, we were able to observe a cognitive and emotional overload in students caused by hidden curriculum. However, we noticed how medical education has been trying to reduce these negative effects. In this sense, it is important to question hegemonic models that influence values, interests, discourses, knowledges, and practices throughout the learning process. In order to do that, it is essential to discuss concepts/actions such as identity, diversity, inclusion, hegemony, ideology, power, and culture, which can occur longitudinally and integrated with curricular units related to Humanities.(AU)

El currículo oculto es resultado de las relaciones interpersonales vividas académicamente que extrapola el currículum formal, pudiendo ser un facilitador y también un obstáculo para el aprendizaje. Esta revisión tiene el objetivo de comprender el abordaje de la temática en la educación médica y su relación con el profesionalismo. La revisión integradora nos permitió observar una sobrecarga cognitiva y emocional de los estudiantes causada por el currículo oculto. Sin embargo, constatamos cómo la educación médica ha trabajado con la finalidad de reducir esos perjuicios. En ese sentido, es importante problematizar los modelos hegemónicos que influyen sobre valores, intereses, discursos, saberes y prácticas durante la formación. Para tanto, es fundamental el debate alrededor de los conceptos/acciones tales como identidad, diversidad, inclusión, hegemonía, ideología, poder y cultura, que puede ocurrir de forma longitudinal e integrada en unidades curriculares relacionadas con las humanidades.(AU)

Environmental monitoring of a landfill area through the application of carbon stable isotopes, chemical parameters and multivariate analysis.

Leachate produced during an organic matter decomposition process has a complex composition and can cause contamination of surface and groundwaters adjacent to a landfill area. The monitoring of these areas is extremely important for the characterization of the leachate produced and to avoid or mitigate environmental damages. Thus, the present study has the objective of monitoring the area of a Brazilian landfill using conventional parameters (dissolved metals and anions in water) and alternative, stable carbon isotopes parameters (δ13C of dissolved organic and inorganic carbons in water) in addition to multivariate analysis techniques. The use of conventional and alternative parameters together with multivariate analysis showed that cells of the residues are at different phases of stabilization of the organic matter and probably already at C3 of the methanogenic phase of decomposition. In addition, the data showed that organic matter stabilization ponds present in the landfill are efficient and improve the quality of the leachate. Enrichment of the heavy 13C isotope in both surface and groundwater suggested contamination in two sampling sites.

New 1,3-benzodioxole derivatives: Synthesis, evaluation of in vitro schistosomicidal activity and ultrastructural analysis.

Schistosomiasis is considered a serious public health problem in 78 countries and territories located in Africa, Asia and America and it is estimated in more than 249 million people infected by any of the species of Schistosoma. The exclusive use of praziquantel (PZQ), effective drug against all species of Schistosoma, has been the basis of the development of a possible resistance against the strains of this parasite. In addition, PZQ is not effective against young forms of worms. Thus, there is a need for the development of new drugs with schistosomicidal activity. The objective of this work was to synthesize and to evaluate the therapeutic potential of new benzodioxole derivatives (3-14) candidates for schistosomicidal drugs. All compounds synthesized showed in vitro schistosomicidal activity. The derivative 12 was considered the best compound, since it took 100% of worms to mortality in the first 72 h of exposure at the concentration of 100 µM and 83.3% at the concentration of 50 µM. Furthermore, male and female adult worms, incubated for 24 h with the compound 12 showed tegument damages characterized by extensive desquamation and edema, tuber destruction, bubble formation and exposure of the muscle layer. This compound has a restricted structure, where the thiazolidinone is attached to the 4-position of the 1,3-benzodioxol ring. The structural conformation of derivative 12 was probably responsible for the promising schistosomicidal activity, where the presence of an electron/conformational restriction of the thiazolidine ring, as well as the action of bromine as a bulk substitute, favored an increase in biological activity. In addition, tegumentary changes caused by derivative 12 may also have been responsible for the death of adult worms of Schistosoma mansoni. Therefore, we verified that the results obtained in this study make benzodioxole derivatives possible candidates for prototypes of new schistosomicidal drugs.

Environmental monitoring of water resources around a municipal landfill of the Rio Grande do Sul state, Brazil.

In Brazil, landfills are commonly used as a method for the final disposal of waste that is compliant with the legislation. This technique, however, presents a risk to surface water and groundwater resources, owing to the leakage of metals, anions, and organic compounds. The geochemical monitoring of water resources is therefore extremely important, since the leachate can compromise the quality and use of surface water and groundwater close to landfills. In this paper, the results of analyses of metals, anions, ammonia, and physicochemical parameters were used to identify possible contamination of surface water and groundwater in a landfill area. A statistical multivariate approach was used. The values found for alkali metals, nitrate, and chloride indicate contamination in the regional groundwater and, moreover, surface waters also show variation when compared to the other background points, mainly for ammonia. Thus, the results of this study evidence the landfill leachate influence on the quality of groundwater and surface water in the study area.

Trichomonas vaginalis NTPDase and ecto-5'-nucleotidase hydrolyze guanine nucleotides and increase extracellular guanosine levels under serum restriction.

Trichomonas vaginalis is the aethiologic agent of trichomoniasis, the most common non-viral sexually transmitted disease in the world. The purinergic signaling pathway is mediated by extracellular nucleotides and nucleosides that are involved in many biological effects as neurotransmission, immunomodulation and inflammation. Extracellular nucleotides can be hydrolyzed by a family of enzymes known as ectonucleotidases including the ecto-nucleoside triphosphate diphosphohydrolases (E-NTPDases) family which hydrolyses nucleosides triphosphate and diphosphate as preferential substrates and ecto-5'-nucleotidase which catalyzes the conversion of monophosphates into nucleosides. In T. vaginalis the E-NTPDase and ecto-5'-nucleotidase activities upon adenine nucleotides have already been characterized in intact trophozoites but little is known concerning guanine nucleotides and nucleoside. These enzymes may exert a crucial role on nucleoside generation, providing the purine sources for the synthesis de novo of these essential nutrients, sustaining parasite growth and survival. In this study, we investigated the hydrolysis profile of guanine-related nucleotides and nucleoside in intact trophozoites from long-term-grown and fresh clinical isolates of T. vaginalis. Knowing that guanine nucleotides are also substrates for T. vaginalis ectoenzymes, we evaluated the profile of nucleotides consumption and guanosine uptake in trophozoites submitted to a serum limitation condition. Results show that guanine nucleotides (GTP, GDP, GMP) were substrates for T. vaginalis ectonucleotidases, with expected kinetic parameters for this enzyme family. Different T. vaginalis isolates (two from the ATCC and nine fresh clinical isolates) presented a heterogeneous hydrolysis profile. The serum culture condition increased E-NTPDase and ecto-5'-nucleotidase activities with high consumption of extracellular GTP generating enhanced GDP, GMP and guanosine levels as demonstrated by HPLC, with final accumulation of the nucleoside. The transcript levels of the five TvNTPDases gene sequences were analyzed by qRT-PCR and the highest gene expressions were found for TvNTPDase 2 and 4. The extracellular guanosine uptake was observed as (13C)GTP nucleotide into parasite DNA and it was lower than that observed for adenosine, labeled as (13C)ATP. These findings indicate the T. vaginalis preference for adenosine uptake and the accumulation of guanosine in the extracellular milieu, corroborating with HPLC data. Our data demonstrate, for the first time, the cascade of guanine nucleotides in T. vaginalis and open possibilities on the study of guanine-related purines other than the classical intracellular activity of G proteins for signal transduction.

Bond strength of self-adhesive resin cements to composite submitted to different surface pretreatments.

OBJECTIVES: Extensively destroyed teeth are commonly restored with composite resin before cavity preparation for indirect restorations. The longevity of the restoration can be related to the proper bonding of the resin cement to the composite. This study aimed to evaluate the microshear bond strength of two self-adhesive resin cements to composite resin. MATERIALS AND METHODS: COMPOSITE DISCS WERE SUBJECT TO ONE OF SIX DIFFERENT SURFACE PRETREATMENTS: none (control), 35% phosphoric acid etching for 30 seconds (PA), application of silane (silane), PA + silane, PA + adhesive, or PA + silane + adhesive (n = 6). A silicone mold containing a cylindrical orifice (1 mm(2) diameter) was placed over the composite resin. RelyX Unicem (3M ESPE) or BisCem (Bisco Inc.) self-adhesive resin cement was inserted into the orifices and light-cured. Self-adhesive cement cylinders were submitted to shear loading. Data were analyzed by two-way ANOVA and Tukey's test (p < 0.05). RESULTS: Independent of the cement used, the PA + Silane + Adhesive group showed higher microshear bond strength than those of the PA and PA + Silane groups. There was no difference among the other treatments. Unicem presented higher bond strength than BisCem for all experimental conditions. CONCLUSIONS: Pretreatments of the composite resin surface might have an effect on the bond strength of self-adhesive resin cements to this substrate.