IMPACTO-MR: um estudo brasileiro de plataforma nacional para avaliar infecções e multirresistência em unidades de terapia intensiva / IMPACTO-MR: a Brazilian nationwide platform study to assess infections and multidrug resistance in intensive care units

RESUMO Objetivo: Descrever o IMPACTO-MR, um estudo brasileiro de plataforma nacional em unidades de terapia intensiva focado no impacto das infecções por bactérias multirresistentes relacionadas à assistência à saúde. Métodos: Descrevemos a plataforma IMPACTO-MR, seu desenvolvimento, critérios para seleção das unidades de terapia intensiva, caracterização da coleta de dados, objetivos e projetos de pesquisa futuros a serem realizados na plataforma. Resultados: Os dados principais foram coletados por meio do Epimed Monitor System® e consistiram em dados demográficos, dados de comorbidades, estado funcional, escores clínicos, diagnóstico de internação e diagnósticos secundários, dados laboratoriais, clínicos e microbiológicos e suporte de órgãos durante a internação na unidade de terapia intensiva, entre outros. De outubro de 2019 a dezembro de 2020, 33.983 pacientes de 51 unidades de terapia intensiva foram incluídos no banco de dados principal. Conclusão: A plataforma IMPACTO-MR é um banco de dados clínico brasileiro de unidades de terapia intensiva focado na pesquisa do impacto das infecções por bactérias multirresistentes relacionadas à assistência à saúde. Essa plataforma fornece dados para o desenvolvimento e pesquisa de unidades de terapia intensiva individuais e ensaios clínicos observacionais e prospectivos multicêntricos.

ABSTRACT Objective: To describe the IMPACTO-MR, a Brazilian nationwide intensive care unit platform study focused on the impact of health care-associated infections due to multidrug-resistant bacteria. Methods: We described the IMPACTO-MR platform, its development, criteria for intensive care unit selection, characterization of core data collection, objectives, and future research projects to be held within the platform. Results: The core data were collected using the Epimed Monitor System® and consisted of demographic data, comorbidity data, functional status, clinical scores, admission diagnosis and secondary diagnoses, laboratory, clinical, and microbiological data, and organ support during intensive care unit stay, among others. From October 2019 to December 2020, 33,983 patients from 51 intensive care units were included in the core database. Conclusion: The IMPACTO-MR platform is a nationwide Brazilian intensive care unit clinical database focused on researching the impact of health care-associated infections due to multidrug-resistant bacteria. This platform provides data for individual intensive care unit development and research and multicenter observational and prospective trials.

Determinants of death in critically ill COVID-19 patients during the first wave of COVID-19: a multicenter study in Brazil.

OBJECTIVE: To evaluate clinical outcomes and factors associated with mortality, focusing on secondary infections, in critically ill patients with COVID-19 in three Brazilian hospitals during the first pandemic wave. METHODS: This was a retrospective observational study involving adult patients with COVID-19 admitted to one of the participating ICUs between March and August of 2020. We analyzed clinical features, comorbidities, source of SARS-CoV-2 infection, laboratory data, microbiology data, complications, and causes of death. We assessed factors associated with in-hospital mortality using logistic regression models. RESULTS: We included 645 patients with a mean age of 61.4 years. Of those, 387 (60.0%) were male, 12.9% (83/643) had undergone solid organ transplant, and almost 10% (59/641) had nosocomial COVID-19 infection. During ICU stay, 359/644 patients (55.7%) required invasive mechanical ventilation, 225 (34.9%) needed renal replacement therapy, 337 (52.2%) received vasopressors, and 216 (33.5%) had hospital-acquired infections (HAIs), mainly caused by multidrug-resistant gram-negative bacteria. HAIs were independently associated with a higher risk of death. The major causes of death were refractory shock and multiple organ dysfunction syndrome but not ARDS, as previously reported in the literature. CONCLUSIONS: In this study, most of our cohort required invasive mechanical ventilation and almost one third had HAIs, which were independently associated with a higher risk of death. Other factors related to death were Charlson Comorbidity Index, SOFA score at admission, and clinical complications during ICU stay. Nosocomial COVID-19 infection was not associated with death. The main immediate causes of death were refractory shock and multiple organ dysfunction syndrome.

Determinants of death in critically ill COVID-19 patients during the first wave of COVID-19: a multicenter study in Brazil / Determinantes de mortalidade em pacientes com COVID-19 em estado crítico durante a primeira onda da doença: estudo multicêntrico no Brasil

ABSTRACT Objective: To evaluate clinical outcomes and factors associated with mortality, focusing on secondary infections, in critically ill patients with COVID-19 in three Brazilian hospitals during the first pandemic wave. Methods: This was a retrospective observational study involving adult patients with COVID-19 admitted to one of the participating ICUs between March and August of 2020. We analyzed clinical features, comorbidities, source of SARS-CoV-2 infection, laboratory data, microbiology data, complications, and causes of death. We assessed factors associated with in-hospital mortality using logistic regression models. Results: We included 645 patients with a mean age of 61.4 years. Of those, 387 (60.0%) were male, 12.9% (83/643) had undergone solid organ transplant, and almost 10% (59/641) had nosocomial COVID-19 infection. During ICU stay, 359/644 patients (55.7%) required invasive mechanical ventilation, 225 (34.9%) needed renal replacement therapy, 337 (52.2%) received vasopressors, and 216 (33.5%) had hospital-acquired infections (HAIs), mainly caused by multidrug-resistant gram-negative bacteria. HAIs were independently associated with a higher risk of death. The major causes of death were refractory shock and multiple organ dysfunction syndrome but not ARDS, as previously reported in the literature. Conclusions: In this study, most of our cohort required invasive mechanical ventilation and almost one third had HAIs, which were independently associated with a higher risk of death. Other factors related to death were Charlson Comorbidity Index, SOFA score at admission, and clinical complications during ICU stay. Nosocomial COVID-19 infection was not associated with death. The main immediate causes of death were refractory shock and multiple organ dysfunction syndrome.

RESUMO Objetivo: Avaliar desfechos clínicos e fatores associados à mortalidade, com foco em infecções secundárias, em pacientes com COVID-19 em estado crítico em três hospitais brasileiros durante a primeira onda da pandemia. Métodos: Estudo observacional retrospectivo envolvendo pacientes adultos com COVID-19 internados nas UTIs participantes entre março e agosto de 2020. Analisaram-se características clínicas, comorbidades, fonte de infecção por SARS-CoV-2, dados laboratoriais, dados microbiológicos, complicações e causas de óbito. Os fatores associados à mortalidade hospitalar foram avaliados por meio de modelos de regressão logística. Resultados: Foram incluídos 645 pacientes com média de idade de 61,4 anos. Desses, 387 (60,0%) eram do sexo masculino, 12,9% (83/643) haviam sido submetidos a transplante de órgão sólido, e quase 10% (59/641) apresentaram infecção nosocomial por COVID-19. Durante a internação na UTI, 359/644 pacientes (55,7%) necessitaram de ventilação mecânica invasiva, 225 (34,9%) necessitaram de terapia renal substitutiva, 337 (52,2%) receberam vasopressores, e 216 (33,5%) apresentaram infecções hospitalares (IHs), causadas principalmente por bactérias Gram-negativas multirresistentes. As IHs associaram-se de forma independente a maior risco de óbito. As principais causas de óbito foram choque refratário e síndrome de disfunção de múltiplos órgãos, mas não SDRA, como relatado anteriormente na literatura. Conclusões: Neste estudo, a maior parte de nossa coorte necessitou de ventilação mecânica invasiva, e quase um terço apresentou IHs, que se associaram de forma independente a maior risco de óbito. Outros fatores relacionados à mortalidade foram Índice de Comorbidade de Charlson, SOFA na admissão e complicações clínicas durante a internação na UTI. A infecção nosocomial por COVID-19 não se associou à mortalidade. As principais causas imediatas de óbito foram choque refratário e síndrome de disfunção de múltiplos órgãos.

Habilidades Sociais Educativas Parentais de Mães de Adolescentes Apontados Como Tendo Problemas de Comportamento / Parenting Social Educational Skills of Mothers of Teenagers Pointed out as Having Behavioral Problems / Habilidades De Educación Social Parental De Madres De Adolescentes Nombrados Con Problemas De Conducta

As habilidades sociais educativas parentais são estratégias que os pais utilizam para direcionar os comportamentos dos filhos diante de situações de interação social. O presente estudo trata-se de uma pesquisa exploratória descritiva que teve por objetivo avaliar as habilidades sociais educativas parentais de mães de adolescentes estudantes de uma escola pública, apontados como tendo problemas sociais de comportamento. Participaram do estudo 20 mães, selecionadas a partir de uma amostragem por conveniência que considerou a ocorrência de queixas pela escola sobre problemas de comportamento de seus filhos. Utilizou-se como instrumento de coleta de dados o Roteiro de Entrevista das Habilidades Sociais Educativas Parentais. Os resultados encontrados apresentaram uma frequência baixa de práticas parentais positivas, em detrimento a uma frequência mais alta de práticas parentais negativas desempenhadas pelas participantes dessa pesquisa. Dessa forma, pode-se concluir um déficit nas habilidades sociais educativas parentais das mães entrevistadas no presente estudo. Esse estudo sugere a necessidade de maior atenção sobre a elaboração e aplicação de programas de treinamentos de habilidades sociais educativas parentais para mães cuidadoras de adolescentes, visto que um possível melhoramento neste aspecto pode influenciar um aprimoramento das estratégias educativas parentais. (AU)

Parenting educational social skills are strategies that parents use to guide their children's behavior in situations of social interaction. This study is an exploratory descriptive research that aimed to assess the social skills related to the parenting practices of mothers of adolescent students from a public school identified as having social behavior problems. Twenty mothers participated in the study, selected from a convenience sampling that considered the occurrence of complaints by the school about their children's behavior problems. As a data collection instrument, the Parental Social Skills Interview Guide was used. The results found showed a low frequency of positive parenting practices to the detriment of a higher frequency of negative parenting practices performed by the participants in this research. Thus, it is possible to conclude a deficit in the parenting educational social skills of the mothers interviewed in the present study. This study suggests the need for greater attention on the design and implementation of training programs for parenting educational social skills for mothers who care for adolescents, since a possible improvement in this aspect may influence an improvement in parenting educational strategies. (AU)

Las habilidades sociales educativas parentales son estrategias que los padres usan para dirigir el comportamiento de sus hijos en situaciones de interacción social. Este estudio es una investigación exploratorio-descriptiva que tuvo como objetivo evaluar las habilidades sociales relacionadas con las prácticas de crianza de madres de estudiantes adolescentes de una escuela pública, apuntados con problemas de conducta social. Veinte madres participaron en el estudio, seleccionado de una muestra de conveniencia que consideró la aparición de quejas por parte de la escuela sobre los problemas de comportamiento de sus hijos. Como instrumento de recopilación de datos, se utilizó la Guía de entrevista de habilidades sociales de los padres. Los resultados encontrados mostraron una baja frecuencia de prácticas de crianza positivas en detrimento de una mayor frecuencia de prácticas de crianza negativas realizadas por los participantes en esta investigación. Por lo tanto, es posible concluir un déficit en las habilidades sociales educativas parentales de las madres entrevistadas en el presente estudio. Este estudio sugiere la necesidad de una mayor atención en el diseño e implementación de programas de capacitación en habilidades sociales educativas parentales para madres que cuidan a adolescentes, ya que una posible mejora en este aspecto puede influir en una mejora en las estrategias educativas para padres. (AU)

Effect of ScLL and 15d-PGJ2 on viability and cytokine release in LPS-stimulated fibroblasts: an in vitro study.

This study evaluated the effect of a cyclopentenone-type PG, 15-Deoxy-Δ12,14-PG J2 (15d-PGJ2), and lectin (ScLL) on the viability of human gingival fibroblasts (HGFs), and on IL-6 and TGFß-1 release by these fibroblasts, stimulated with lipopolysaccharide (LPS). HGFs were stimulated with LPS 10 µg/ml and treated with 15d-PGJ2 1 and 2 µg/ml, and ScLL 2 and 5 µg/ml, for 1 and 3h, and then evaluated for viability by MTT assay. Supernatant was collected to detect IL-6 and TGFß-1 release, by ELISA. Positive control was cells kept in Dulbecco's Modified Eagle's Medium, and negative control was those kept in LPS. Data were analyzed by ANOVA and Dunnett's test (α = 0.05). No significant difference was found in viability among experimental groups at 1h (p > 0.05). Percentage of ScLL 5 µg/ml viable cells was similar to that of positive control at evaluated periods (p > 0.05), whereas the other groups had lower levels than the positive control (p < 0.05). IL-6 release was statistically higher for ScLL 5 µg/ml and 15d-PGJ2 2 µg/ml at 1h, compared with the other treated groups and positive control (p < 0.05). No significant differences were found among the groups at 3h (p > 0.05), except for ScLL 2 µg/ml and 15d-PGJ2 1 µg/ml, which showed lower IL-6 release compared with that of negative control (p < 0.05). No significant difference was found among the groups for TGFß-1 release (p > 0.05). Results indicated that ScLL 5 µg/ml did not interfere in viability, and ScLL 2 µg/ml and 15d-PGJ2 1 µg/ml demonstrated reduced IL-6 release. Tested substances had no effect on TGFß-1 release.

Human B cells infected by Trypanosoma cruzi undergo F-actin disruption and cell death via caspase-7 activation and cleavage of phospholipase Cgama1

B cells contribute to the immune system in many ways such as antigen presentation to CD4+ T cells, secretion of cytokines and lymphoid tissue organogenesis. Furthermore, they are the only cell type capable of producing immunoglobulins. B cells also account for critical aspects of the resistance against intracellular pathogens. Trypanosoma cruzi is an intracellular parasite that sabotages humoral response by depletion of immature B cells. Polyclonal activation and secretion of non-specific antibodies are also other mechanisms used by T cruzi to evade and subvert the mammalian host immune system, leading to increased parasitemia and susceptibility to Chagas’ disease. It remained unclear whether B cell depletion occurs due to direct contact with T. cruzi or results from a global increase in inflammation. Unlike previous reports, we demonstrated in this study that T. cruzi infects human B cells, resulting in parasite-induced activation of caspase-7 followed by proteolytic cleavage of phospholipase Cgama1 and cell death. These data contribute to explain the mechanisms ruling B-cell depletion and evasion of the immune response by T. cruzi.

Human B cells infected by Trypanosoma cruzi undergo F-actin disruption and cell death via caspase-7 activation and cleavage of phospholipase Cgama1

B cells contribute to the immune system in many ways such as antigen presentation to CD4+ T cells, secretion of cytokines and lymphoid tissue organogenesis. Furthermore, they are the only cell type capable of producing immunoglobulins. B cells also account for critical aspects of the resistance against intracellular pathogens. Trypanosoma cruzi is an intracellular parasite that sabotages humoral response by depletion of immature B cells. Polyclonal activation and secretion of non-specific antibodies are also other mechanisms used by T cruzi to evade and subvert the mammalian host immune system, leading to increased parasitemia and susceptibility to Chagas’ disease. It remained unclear whether B cell depletion occurs due to direct contact with T. cruzi or results from a global increase in inflammation. Unlike previous reports, we demonstrated in this study that T. cruzi infects human B cells, resulting in parasite-induced activation of caspase-7 followed by proteolytic cleavage of phospholipase Cgama1 and cell death. These data contribute to explain the mechanisms ruling B-cell depletion and evasion of the immune response by T. cruzi.

Effect of ScLL and 15d-PGJ2 on viability and cytokine release in LPS-stimulated fibroblasts: an in vitro study

Abstract This study evaluated the effect of a cyclopentenone-type PG, 15-Deoxy-Δ12,14-PG J2 (15d-PGJ2), and lectin (ScLL) on the viability of human gingival fibroblasts (HGFs), and on IL-6 and TGFβ-1 release by these fibroblasts, stimulated with lipopolysaccharide (LPS). HGFs were stimulated with LPS 10 μg/ml and treated with 15d-PGJ2 1 and 2 μg/ml, and ScLL 2 and 5 μg/ml, for 1 and 3h, and then evaluated for viability by MTT assay. Supernatant was collected to detect IL-6 and TGFβ-1 release, by ELISA. Positive control was cells kept in Dulbecco's Modified Eagle's Medium, and negative control was those kept in LPS. Data were analyzed by ANOVA and Dunnett's test (α = 0.05). No significant difference was found in viability among experimental groups at 1h (p > 0.05). Percentage of ScLL 5 µg/ml viable cells was similar to that of positive control at evaluated periods (p > 0.05), whereas the other groups had lower levels than the positive control (p < 0.05). IL-6 release was statistically higher for ScLL 5 μg/ml and 15d-PGJ2 2 µg/ml at 1h, compared with the other treated groups and positive control (p < 0.05). No significant differences were found among the groups at 3h (p > 0.05), except for ScLL 2 µg/ml and 15d-PGJ2 1 µg/ml, which showed lower IL-6 release compared with that of negative control (p < 0.05). No significant difference was found among the groups for TGFβ-1 release (p > 0.05). Results indicated that ScLL 5 μg/ml did not interfere in viability, and ScLL 2 µg/ml and 15d-PGJ2 1 µg/ml demonstrated reduced IL-6 release. Tested substances had no effect on TGFβ-1 release.

Trypanosoma cruzi modulates gene expression of plasma membrane repair-related proteins.

Plasma membrane injury and repair is particularly prevalent in muscle cells. Here, we aimed to verify dysferlin, acid sphingomyelinase and transcriptional factor EB gene expression during Trypanosoma cruzi infection in vitro and in vivo. Our results showed that the parasite modulates gene expression of these proteins in a way dependent on the number of plasma membrane interacting parasites and in a rapamycin-sensitive manner.

Effect of lectin (ScLL) on fibroblasts stimulated with LPS - an in vitro study.

The lectin (ScLL) extracted from the Synadenium carinatum plant has been evaluated as an immunomodulator in diseases such as asthma, neosporosis and leishmaniasis. However, it has not yet been evaluated in the oral cavity. This study evaluated the effect of ScLL on viability, proliferation and release of IL-10 in human gingival fibroblasts (HGF) stimulated with lipopolysaccharide (LPS). HGF were stimulated with LPS 1 µg/ml and treated with ScLL in concentrations of 10, 5 and 2 µg/ml for 1 and 5 h, and evaluated by flow cytometry for viability, apoptosis (initial/advanced) and necrosis. The supernatant was collected to detect release of IL-10 by ELISA. The proliferation was assessed with the BrdU assay. Positive control consisted of cells maintained in Dulbecco's Modified Eagles Medium (DMEM), and the negative control, of those kept in tap water. Data were analyzed by ANOVA and Dunnett's test (α = 0.05). No significant difference was found for ScLL concentrations regarding viability or initial and advanced apoptosis (p=0.455). All the groups, including the positive control, had a significantly lower necrosis parameter than negative control at 5 h (p < 0.001). No difference was found for proliferation among the experimental groups (p = 0.832). ScLL at 5 and 2 µg/ml resulted in a lower release of IL-10 than positive and negative controls at 5 h (p = 0.047). The results indicated that ScLL concentrations tested were not cytotoxic, and had no effect on proliferation and release of IL-10 parameters. A thorough understanding of ScLL, regarding its immunomodulatory potential, may open the door to new perspectives for dentistry.

Effect of lectin (ScLL) on fibroblasts stimulated with LPS - an in vitro study

Abstract: The lectin (ScLL) extracted from the Synadenium carinatum plant has been evaluated as an immunomodulator in diseases such as asthma, neosporosis and leishmaniasis. However, it has not yet been evaluated in the oral cavity. This study evaluated the effect of ScLL on viability, proliferation and release of IL-10 in human gingival fibroblasts (HGF) stimulated with lipopolysaccharide (LPS). HGF were stimulated with LPS 1 µg/ml and treated with ScLL in concentrations of 10, 5 and 2 µg/ml for 1 and 5 h, and evaluated by flow cytometry for viability, apoptosis (initial/advanced) and necrosis. The supernatant was collected to detect release of IL-10 by ELISA. The proliferation was assessed with the BrdU assay. Positive control consisted of cells maintained in Dulbecco's Modified Eagles Medium (DMEM), and the negative control, of those kept in tap water. Data were analyzed by ANOVA and Dunnett's test (α = 0.05). No significant difference was found for ScLL concentrations regarding viability or initial and advanced apoptosis (p=0.455). All the groups, including the positive control, had a significantly lower necrosis parameter than negative control at 5 h (p < 0.001). No difference was found for proliferation among the experimental groups (p = 0.832). ScLL at 5 and 2 µg/ml resulted in a lower release of IL-10 than positive and negative controls at 5 h (p = 0.047). The results indicated that ScLL concentrations tested were not cytotoxic, and had no effect on proliferation and release of IL-10 parameters. A thorough understanding of ScLL, regarding its immunomodulatory potential, may open the door to new perspectives for dentistry.

Activation of spleen cells by ArtinM may account for its immunomodulatory properties.

ArtinM is a D-mannose-binding lectin extracted from Artocarpus heterophyllus that promotes interleukin-12 production by macrophages and dendritic cells. This property is considered responsible for T helper 1 immunity induced in vivo after ArtinM administration. In this study, we investigated the effect of native (jArtinM) and recombinant (rArtinM) forms of lectin on murine spleen cells and isolated T lymphocytes. We found that ArtinM binds to the surface of spleen cells. This interaction, which was blocked by D-mannose, induced cell activation, as manifested by increased mitochondrial activity, interleukin-2 production, and cell proliferation. We verified that a 30-times higher concentration of rArtinM was required to trigger optimal activation of spleen cells compared with that needed with jArtinM, although these proteins have identical sugar recognition properties and use the same signaling molecules to trigger cell activation. Because the distinction between native and recombinant is restricted to their tertiary structure (tetrameric and monomeric, respectively), we postulated that the multi-valence of jArtinM accounts for its superiority in promoting clustering of cell surface glycoreceptors and activation. The jArtinM and rArtinM activation effect exerted on spleen cells was reproduced on purified CD4(+) T cells. Our results suggest that ArtinM interaction with T cells leads to responses that may act in concert with the interleukin-12 produced by antigen-presenting cells to modulate immunity toward the T helper 1 axis. Further studies are necessary to dissect ArtinM/T-cell interactions to more fully understand the immunomodulation induced by carbohydrate recognition.

Levels of immunoglobulin A1 in peri-implant fluid and saliva from patients with mucositis: a preliminary study.

There are no studies evaluating the possible use of immunoglobulin A1 (IgA1) as an early marker for peri-implant inflammation. The aim of this study was to evaluate the IgA1 levels in peri-implant sulcular fluid (PISF) and saliva of partially edentulous patients as an indicator of mucositis. Twenty-seven patients were examined to determine the peri-implant status based on probing depth and bleeding on probing. Saliva and PISF around dental implants were collected and the IgA1 levels were evaluated by Elisa assay. IgA1 in saliva and PISF of these patients were compared and their correlations with clinical parameters were evaluated. Differences in IgA1 levels in saliva (821.1 ± 290.6; 779.8 ± 401.5) and PISF (26.6 ± 20.7; 25.1 ± 20.5) of healthy and mucositis groups, respectively were not observed (p>0.05). Correlation between clinical parameters and IgA1 in saliva or PISF was not observed in healthy or mucositis groups (p=0.607; p=0.826, respectively). These results suggest that IgA1 cannot be used as an immunological marker of mucositis.

Levels of Immunoglobulin A1 in Peri-Implant Fluid and Saliva from Patients with Mucositis: A Preliminary Study

There are no studies evaluating the possible use of immunoglobulin A1 (IgA1) as an early marker for peri-implant inflammation. The aim of this study was to evaluate the IgA1 levels in peri-implant sulcular fluid (PISF) and saliva of partially edentulous patients as an indicator of mucositis. Twenty-seven patients were examined to determine the peri-implant status based on probing depth and bleeding on probing. Saliva and PISF around dental implants were collected and the IgA1 levels were evaluated by Elisa assay. IgA1 in saliva and PISF of these patients were compared and their correlations with clinical parameters were evaluated. Differences in IgA1 levels in saliva (821.1 ± 290.6; 779.8 ± 401.5) and PISF (26.6 ± 20.7; 25.1 ± 20.5) of healthy and mucositis groups, respectively were not observed (p>0.05). Correlation between clinical parameters and IgA1 in saliva or PISF was not observed in healthy or mucositis groups (p=0.607; p=0.826, respectively). These results suggest that IgA1 cannot be used as an immunological marker of mucositis.

Não existem estudos que avaliem a utilização de imunoglobulina A1 (IgA1) como marcador precoce da inflamação peri-implantar. O objetivo deste estudo foi avaliar os níveis de IgA1 do fluido sulcular peri-implantar (PISF) e saliva de pacientes parcialmente desdentados como indicador da mucosite. Vinte e sete pacientes foram examinados para determinar a condição peri-implantar com base na profundidade de sondagem e sangramento à sondagem. Saliva e PISF ao redor de implantes dentários foram coletados e os níveis IgA1 foram avaliados pelo teste Elisa. IgA1 na saliva e PISF destes pacientes foram comparados e suas correlações com parâmetros clínicos foram avaliados. Não foram observadas diferenças nos níveis de IgA1 (821,1 ± 290,6; 779,8 ± 401,5) na saliva e PISF (26,6 ± 20,7; 25,1 ± 20,5) de grupos saudáveis e mucosite, respectivamente (p>0,05). Correlação entre os parâmetros clínicos e IgA1 na saliva ou PISF não foi observada em grupos saudáveis ou mucosite (p=0,607; p=0,826, respectivamente). Estes resultados demonstraram que IgA1 não pode ser utilizada como marcador imunológico da mucosite.

Cytotoxic response of two cell lines exposed in vitro to four endodontic sealers

Aim: To investigate the cytotoxicity of four endodontic sealers with different bases – Epiphany(EPH), AH Plus (AHP), Sealer 26 (S26) and Endofill (ENF) – on human foreskin fibroblasts(HFF) and mouse macrophages (J774/G8). Methods: Cells were placed in direct contact withfreshly prepared endodontic sealers in polypropylene tubes. The cells were incubated for 24, 48and 72 h. Cytotoxicity was assessed using the MTT assay (cell viability) and Griess reagent (NOrelease). Results: On the HFF cultures, EPH showed the lowest viability levels of all four sealersat 24 h (p<0.05), but over time (72h), EPH lessened its toxic levels in a similar pattern as the otherthree materials (p>0.05). The viability of all four sealers on the macrophage cultures showed nostatistically significant difference over time, except between EPH and AHP at 72 h (p<0.05).Although uniformity was not detected in macrophage and fibroblast release of NO in response tosealers over time, a trend of increased NO levels for EPH (p<0.05) was observed. Conclusions:The response pattern varied depending on time and type of cell line used for analysis, althoughthe results indicate a higher cytotoxicity for EPH in short-term tests.

Cytotoxicity of bovine and porcine collagen membranes in mononuclear cells.

This study compared the cytotoxicity and the release of nitric oxide induced by collagen membranes in human mononuclear cells. Peripheral blood was collected from each patient and the separation of mononuclear cells was performed by Ficoll. Then, 2x10(5) cells were plated in 48-well culture plates under the membranes in triplicate. The polystyrene surface was used as negative control. Cell viability was assessed by measuring mitochondrial activity (MTT) at 4, 12 and 24 h, with dosage levels of nitrite by the Griess method for the same periods. Data had non-normal distribution and were analyzed by the Kruskal-Wallis test (p<0.05). Statistically significant differences (p<0.05) were observed between the membranes and the control in the experimental period, although there was a significant reduction in viability over time (p<0.01). At 4 and 12 h, the porcine membrane induced a higher release of nitrite compared with the control and bovine membrane, respectively (p<0.01), and this difference was maintained at 24 h (p<0.05). This in vitro study showed that the porcine collagen membrane induces an increased production of proinflammatory mediators by mononuclear cells in the first hours of contact, decreasing with time.

Cytotoxicity of bovine and porcine collagen membranes in mononuclear cells

This study compared the cytotoxicity and the release of nitric oxide induced by collagen membranes in human mononuclear cells. Peripheral blood was collected from each patient and the separation of mononuclear cells was performed by Ficoll. Then, 2x10(5) cells were plated in 48-well culture plates under the membranes in triplicate. The polystyrene surface was used as negative control. Cell viability was assessed by measuring mitochondrial activity (MTT) at 4, 12 and 24 h, with dosage levels of nitrite by the Griess method for the same periods. Data had non-normal distribution and were analyzed by the Kruskal-Wallis test (p<0.05). Statistically significant differences (p<0.05) were observed between the membranes and the control in the experimental period, although there was a significant reduction in viability over time (p<0.01). At 4 and 12 h, the porcine membrane induced a higher release of nitrite compared with the control and bovine membrane, respectively (p<0.01), and this difference was maintained at 24 h (p<0.05). This in vitro study showed that the porcine collagen membrane induces an increased production of proinflammatory mediators by mononuclear cells in the first hours of contact, decreasing with time.

Neste estudo foi comparada a citoxicidade e a liberação de nitrito induzidos por membranas de colágeno bovino e suíno em células mononucleares humanas. Foram coletados sangue periférico de cada paciente, e realizada separação de mononucleares por gradiente de Ficoll. Um total de 2x10(5) células foram plaqueadas em placas de cultura de 48 poços sob as membranas, em triplicata. O poço sem membrana serviu como controle negativo. A viabilidade celular foi avaliada medindo a atividade mitocondrial (MTT) em 4,12 e 24 h, com dosagens dos níveis de nitrito pelo método de Griess nos mesmos períodos. As amostras não apresentaram distribuição normal, sendo realizado o teste de Kruskal-Wallis (p<0,05). Foram observadas diferenças estatisticamente significantes entre as membranas e o controle nos período analisados (p<0,05), embora tenha ocorrido redução da viabilidade em função do tempo (p<0,01). Em 4 e 12 h a membrana suína induziu maior liberação de nitrito comparado ao controle e à membrana bovina, respectivamente (p<0,01). Tal diferença foi mantida em 24 h (p<0,05). Este estudo in vitro demonstrou que a membrana colágena suína induz uma maior produção de mediador pró-inflamatório pelas células mononucleares nas primeiras horas de contato, diminuindo com o tempo.

Effect of titanium surface on secretion of IL1ß and TGFß1 by mononuclear cells.

Mononuclear cells play an important role in the modulation of healing. The characteristics of implant surface topography may alter the production of signaling molecules such as cytokines. The aim of this in vitro study was to evaluate the effects of commercially available titanium surface treatments on both cell viability and the secretion of the antagonist cytokines, IL1ß and TGFß1. Human mononuclear cells were cultured on 10 mm diameter commercially pure titanium (cpTi) disks that were prepared using a turning procedure (control = machined surface) and either acid etched or bio-anodized for 1-7 days. Adhered cells were investigated with respect to cell viability using an MTT assay, and cytokine production was verified using an ELISA assay. The results indicate that surface characteristics did not alter the cell viability at days 1 and 4, although the machined surface presented the highest absorbance values at day 7 (p = 0.0084). Cell viability was reduced throughout the time course for all analyzed surfaces (p < 0.05). On day 4, IL1ß levels were significantly higher on bio-anodized compared to acid etched surfaces (p = 0.0097). TGFß1 did not show differences among the surfaces at days 1 and 4. The responses of non-stimulated mononuclear cells to titanium surfaces suggest only modest effects of the surface treatment and roughness on pro-inflammatory cytokine (IL1ß) release.

Effect of titanium surface on secretion of IL1β and TGFβ1 by mononuclear cells

Mononuclear cells play an important role in the modulation of healing. The characteristics of implant surface topography may alter the production of signaling molecules such as cytokines. The aim of this in vitro study was to evaluate the effects of commercially available titanium surface treatments on both cell viability and the secretion of the antagonist cytokines, IL1β and TGFβ1. Human mononuclear cells were cultured on 10 mm diameter commercially pure titanium (cpTi) disks that were prepared using a turning procedure (control=machined surface) and either acid etched or bio-anodized for 1-7 days. Adhered cells were investigated with respect to cell viability using an MTT assay, and cytokine production was verified using an ELISA assay. The results indicate that surface characteristics did not alter the cell viability at days 1 and 4, although the machined surface presented the highest absorbance values at day 7 (p = 0.0084). Cell viability was reduced throughout the time course for all analyzed surfaces (p < 0.05). On day 4, IL1β levels were significantly higher on bio-anodized compared to acid etched surfaces (p = 0.0097). TGFβ1 did not show differences among the surfaces at days 1 and 4. The responses of non-stimulated mononuclear cells to titanium surfaces suggest only modest effects of the surface treatment and roughness on pro-inflammatory cytokine (IL1β) release.

Xylitol inhibits J774A.1 macrophage adhesion in vitro

The aim of this work was to evaluate the effect of xylitol on J774A.1 macrophage adhesion. Adhesion consisted of a three-hour interval, at room temperature, followed by washing and cell incubation at 37ºC/5 percent CO2/ 48h. Xylitol was used to treat the cells either before (for 24h) or after the cell incubation (for 48h) at 5 percent as final concentration in both the situations. It was found that xylitol was effective in preventing the adhesion in both the conditions in spite of the former being 100-fold greater and significant (p < 0.001). The results pointed to an important xylitol action on macrophage adhesion, which should be further investigated as an inflammatory control.