RESUMO

OBJECTIVE: To evaluate whether antimicrobial photodynamic therapy (aPDT) repairs bisphosphonate-related osteonecrosis of the jaw (BRONJ) modulated by the reduction of NF-kB protein in a murine model. METHODOLOGY: Male Wistar rats (N=30) were divided into the following groups (n=6/group): negative control (NC); experimental osteonecrosis (ONE); ONE + photosensitizer (PS); ONE + photobiomodulation (PBM); and ONE + aPDT. Over 8 weeks, ONE was induced by zoledronic acid 250 µg/kg injections, except in the NC group, which received sterile 0.9% saline, followed by extraction of the lower left first molar. Red light laser irradiation (wavelength ~660 nm, power 50 mW, energy of 2 J, energy dose of 66.67 J/cm2 for 40 s) was performed once a week for 4 weeks. Methylene blue 0.3% was used as PS. The animals were euthanized and examined macroscopically for the presence of exposed bone and epithelial repair and microscopically by histochemical (hematoxylin-eosin and Masson's trichrome staining) and immunohistochemical (anti-NF-kB) methods. Macroscopic and histomorphometric data were analyzed by one-way ANOVA and Tukey's post-test (p<0.05). RESULTS: Mucosal repair, viable osteocytes, and NF-kB immunostaining were observed in the NC, ONE+PS, ONE+PBM, and ONE+aPDT groups. The ONE group showed no mucosal repair, showing empty lacunae and multifocal immunostaining for NF-kB. The ONE+PBM and ONE+aPDT groups had greater deposition of extracellular matrix and less necrotic bone tissue (p<0.05). CONCLUSION: PBM and aPDT treatments for BRONJ were effective for bone and epithelial repair, in addition to reducing inflammation mediated by the decrease of NF-kB protein in the irradiated regions.

Assuntos

Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Modelos Animais de Doenças , Imuno-Histoquímica , NF-kappa B , Fotoquimioterapia , Fármacos Fotossensibilizantes , Ratos Wistar , Animais , Masculino , Fotoquimioterapia/métodos , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/patologia , NF-kappa B/análise , Fármacos Fotossensibilizantes/farmacologia , Fatores de Tempo , Reprodutibilidade dos Testes , Ácido Zoledrônico/farmacologia , Resultado do Tratamento , Imidazóis/farmacologia , Difosfonatos/farmacologia , Terapia com Luz de Baixa Intensidade/métodos , Azul de Metileno/farmacologia , Azul de Metileno/uso terapêutico , Análise de Variância , Distribuição Aleatória , Conservadores da Densidade Óssea/farmacologia

RESUMO

Abstract Objective To evaluate whether antimicrobial photodynamic therapy (aPDT) repairs bisphosphonate-related osteonecrosis of the jaw (BRONJ) modulated by the reduction of NF-kB protein in a murine model. Methodology Male Wistar rats (N=30) were divided into the following groups (n=6/group): negative control (NC); experimental osteonecrosis (ONE); ONE + photosensitizer (PS); ONE + photobiomodulation (PBM); and ONE + aPDT. Over 8 weeks, ONE was induced by zoledronic acid 250 µg/kg injections, except in the NC group, which received sterile 0.9% saline, followed by extraction of the lower left first molar. Red light laser irradiation (wavelength ~660 nm, power 50 mW, energy of 2 J, energy dose of 66.67 J/cm2 for 40 s) was performed once a week for 4 weeks. Methylene blue 0.3% was used as PS. The animals were euthanized and examined macroscopically for the presence of exposed bone and epithelial repair and microscopically by histochemical (hematoxylin-eosin and Masson's trichrome staining) and immunohistochemical (anti-NF-kB) methods. Macroscopic and histomorphometric data were analyzed by one-way ANOVA and Tukey's post-test (p<0.05). Results Mucosal repair, viable osteocytes, and NF-kB immunostaining were observed in the NC, ONE+PS, ONE+PBM, and ONE+aPDT groups. The ONE group showed no mucosal repair, showing empty lacunae and multifocal immunostaining for NF-kB. The ONE+PBM and ONE+aPDT groups had greater deposition of extracellular matrix and less necrotic bone tissue (p<0.05). Conclusion PBM and aPDT treatments for BRONJ were effective for bone and epithelial repair, in addition to reducing inflammation mediated by the decrease of NF-kB protein in the irradiated regions.

RESUMO

Experimental models that consider host-pathogen interactions are relevant for improving knowledge about oral candidiasis. The aim of this study was to assess the epithelial immune responses, Candida penetration of cell monolayers, and virulence during mixed species culture infections. Single species cultures of Candida albicans and mixed cultures (C. albicans, Streptococcus mutans, and Streptococcus sanguinis) were used to infect monolayers of HaCaT and FaDu ATCC HTB-43 cells for 12 h. After infection, IL-18 and IL-34 gene expression was measured to assess epithelial cell immune responses, and lactate dehydrogenase (LDH) activity was measured as an indicator of cell damage. Microscopy determined C. albicans morphology and penetration of fungal cells through the keratinocyte monolayer. Monolayers devoid of infection served as controls. Data were analyzed by an ANOVA one-way test followed by Tukey's post-hoc test (α = 0.05). The results found that IL-18 and IL-34 gene expression and LDH activity were significantly (p < 0.05) upregulated for both cell lines exposed to mixed species cultures compared with C. albicans alone. Candida albicans yeast and hyphae were evident in C. albicans only infections. In contrast, monolayers infected by C. albicans, S. mutans, and S. sanguinis exhibited higher microbial invasion with several hyphal aggregates detected. The presence of streptococci in C. albicans infection enhances the virulence and pathogenicity of the fungus with associated increased immune responses and tissue damage. Extrapolation of these findings to oral infection would indicate the added potential benefit of managing bacterial components of biofilms during treatment.

Assuntos

Candida albicans , Interleucina-18 , Virulência , Interleucina-18/metabolismo , Streptococcus , Streptococcus mutans/fisiologia , Biofilmes

RESUMO

Abstract Experimental models that consider host-pathogen interactions are relevant for improving knowledge about oral candidiasis. The aim of this study was to assess the epithelial immune responses, Candida penetration of cell monolayers, and virulence during mixed species culture infections. Single species cultures of Candida albicans and mixed cultures (C. albicans, Streptococcus mutans, and Streptococcus sanguinis) were used to infect monolayers of HaCaT and FaDu ATCC HTB-43 cells for 12 h. After infection, IL-18 and IL-34 gene expression was measured to assess epithelial cell immune responses, and lactate dehydrogenase (LDH) activity was measured as an indicator of cell damage. Microscopy determined C. albicans morphology and penetration of fungal cells through the keratinocyte monolayer. Monolayers devoid of infection served as controls. Data were analyzed by an ANOVA one-way test followed by Tukey's post-hoc test (α = 0.05). The results found that IL-18 and IL-34 gene expression and LDH activity were significantly (p < 0.05) upregulated for both cell lines exposed to mixed species cultures compared with C. albicans alone. Candida albicans yeast and hyphae were evident in C. albicans only infections. In contrast, monolayers infected by C. albicans, S. mutans, and S. sanguinis exhibited higher microbial invasion with several hyphal aggregates detected. The presence of streptococci in C. albicans infection enhances the virulence and pathogenicity of the fungus with associated increased immune responses and tissue damage. Extrapolation of these findings to oral infection would indicate the added potential benefit of managing bacterial components of biofilms during treatment.

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Resumo O objetivo deste estudo foi avaliar a resposta epithelial imune, a colonização da Candida albicans em monocamadas celulares e sua virulência em resposta a infecções de culturas de biofilme multiespécie. Culturas de biofilme monoespécie de C. albicans e culturas mistas (C. albicans, Streptococcus mutans e Streptococcus sanguinis) foram utilizadas para infectar monocamadas de células HaCaT e FaDu por 12 h. Após a infecção, a expressão dos genes IL-18 e IL-34 foi medida para avaliar as respostas imunes das células epiteliais. A atividade da lactato desidrogenase (LDH) foi medida como um indicador de dano celular. A microscopia determinou a morfologia de C. albicans e a penetração das células fúngicas através da monocamada de queratinócitos. Monocamadas em que não houve infecção serviram como controles. Os dados foram analisados por um teste ANOVA one-way seguido pelo teste post-hoc de Tukey (α = 0,05). Os resultados demonstraram que a expressão gênica de IL-18 e IL-34 e a atividade de LDH foram (p < 0,05) reguladas positivamente para ambas as linhagens de células expostas a culturas de espécies mistas em comparação com C. albicans isoladamente. Leveduras de C.albicans e hifas foram evidentes em infecções apenas por C. albicans. Entretanto, monocamadas infectadas por C. albicans, S. mutans e S. sanguinis exibiram maior invasão microbiana com vários agregados de hifas detectados. Dessa maneira, a presença de estreptococos na infecção por C. albicans aumentou a virulência e a patogenicidade do fungo com respostas imunes aumentadas associadas a danos nos tecidos. A extrapolação desses achados para a infecção oral indicaria o potencial benéfico do controle dos componentes bacterianos em biofilmes durante a terapia da candidíase

RESUMO

AIMS: To evaluate the unstimulated salivary flow (USF) and salivary colonization of total Streptococcus spp. (TS) and mutans-group (MS) in pediatric patients with hematological tumors. Correlations of salivary and microbiological changes with chemotherapy and patient-related factors were also verified. METHODS AND RESULTS: Eligible children (n = 31) were evaluated before (control) and after (2, 5, and 10-weeks) the chemotherapy protocol was applied. Saliva samples were collected by the traditional spitting method to determine the USF (ml/min). Salivary TS and MS were determined by colony-forming units (CFU ) counts in a selective medium. The caries experience was evaluated by DMFT/dmft indexes. Data were submitted to Student's t-test, one-way ANOVA, and correlation tests (α = 0.05). The USF rate at baseline was 0.89 (±0.73) ml/min with up to 20% reduction during the follow-up and did not differ statistically during chemotherapy (p  > .05). Chemotherapy did not modify the salivary TS load (p > .05), but induced a dysbiotic shift with higher MS counts (∼ 5 fold-increase) at 10-weeks (p < .05). There is a correlation of USF with age (r = .390) and SM load with caries experience (rs  = -.540) at 5-weeks. CONCLUSION: Chemotherapy may promote a specific increase of mutans-group streptococci without changing the Streptococcus spp. load and unstimulated saliva flow. Correlation reinforced the need for further enlightenment about the chemotherapy mechanisms in the salivary and microbiological parameters.

Assuntos

Cárie Dentária , Neoplasias Hematológicas , Criança , Índice CPO , Humanos , Estudos Longitudinais , Saliva , Streptococcus mutans

RESUMO

Diabetes mellitus is one of the most prevalent diseases worldwide. The glucose levels found in the blood of diabetic patients can be reflected in the saliva, which can favor biofilm growth and predispose denture wearers to oral candidiasis. This study aimed to evaluate the effect of different salivary glucose concentrations on dual-species biofilms of Candida albicans and Streptococcus mutans. A 96-h biofilm was developed on acrylic resin specimens exposed to 'feast' (10% sucrose) and 'famine' periods. Biofilms were constantly exposed to salivary glucose concentrations equivalent to 0, 20, 60 and 100 mM. Higher salivary glucose concentrations resulted in increased counts of C. albicans and a higher quantity of insoluble extracellular polysaccharides. All biofilms presented high phospholipase activity. The biofilms were characterized by the predominance of yeast cells and microcolonies in all the groups analyzed with co-localization of both species. Higher salivary glucose concentrations formed more robust and potentially virulent biofilms.

Assuntos

Candida albicans , Streptococcus mutans , Biofilmes , Glucose , Humanos , Saliva

RESUMO

BACKGROUND: This study aimed to investigate the influence of oral health on nutritional status, self-perception of oral health and health related quality of life of institutionalized elders. MATERIAL AND METHODS: A cross-sectional study was conducted with 193 institutionalized elders living in the metropolitan region of João Pessoa (Brazil). The independent variables included were: 1) caries experience (DMFT index and its components); 2) use and need of dental prostheses; and 3) type of edentulism. The dependent variables included were related to nutritional status, self-perception of oral health and health-related quality of life. Data were submitted to a descriptive and comparative analysis, through correlation, association and difference tests, considering a significance level of 5% (p<0.05). RESULTS: No statistical significant correlations or associations between the oral health status and nutritional status and quality of life were found (p>0.05). Individuals who did not need prosthesis had higher scores for nutritional status. Self-perception of oral health and health-related quality of life did not vary significantly according to the studied variables. CONCLUSIONS: The oral health status has a limited impact on the nutritional status, and does not impact the self-perception of oral health and quality of life of the institutionalized elders. Key words:Nursing homes, oral health, quality of life.

RESUMO

INTRODUCTION: Institutionalized older adults have higher risks of diseases and worse health-related quality of life (HRQoL) than noninstitutionalized. OBJECTIVE: To evaluate the influence of physical state, nutritional status and self-perceived general health and oral health on the quality of life of institutionalized older adults in two Brazilian cities. METHODS: A multicenter cross-sectional study was conducted in 17 homes for the aged of two Brazilian cities. Six trained researchers interviewed 344 older adults. The performance of activities of daily living (Katz scale) and frailty status (Fried scale) were applied to evaluate the physical state. The Mini Nutritional Assessment Short-Form (MNA-SF®) and the body composition were used to screening the nutritional status. A hand dynamometer was used to measure the dominant hand grip strength. The 12-Item Short Form Survey for self-perceived health (SF-12) was used to determine the HRQoL. A Likert scale was used to assess the general and oral health self-perception. Multiple Poisson regression model was applied to analyze the data (α = 0.05). RESULTS: The mean (SD) score of the SF-12 was 60.89 (14.50) points. The factors associated with the highest SF-12 score were being able to walk, being nonfrail, being normal nourished, taking fewer medications, having greater dominant hand grip strength and higher self- perceived general health (p < 0.05). CONCLUSION: Better HRQoL in institutionalized older adults was associated with better physical state, nutritional status and self-perceived general health.

Assuntos

Atividades Cotidianas , Qualidade de Vida , Idoso , Brasil , Estudos Transversais , Avaliação Geriátrica , Força da Mão , Humanos , Avaliação Nutricional , Estado Nutricional

RESUMO

BACKGROUND: In oral candidiasis models, Candida albicans and Streptococcus salivarius sp. biofilms have an antagonistic relationship. Due to this, S. salivarius have been used experimentally as probiotic. However, the interaction between these microorganisms in the peri-implantitis-like microenvironment remains unknown. This study aimed to evaluate the interaction between C. albicans and S. salivarius biofilms developed on titanium surfaces, under reduced oxygen levels. METHODS: Titanium specimens were pre-conditioned with artificial saliva (1 h, 37 °C). Single-species biofilms of C. albicans (ATCC 90028) and co-culture biofilms of C. albicans and S. salivarius (ATCC 7073) was developed for 24 and 72 h on titanium specimens. Subsequently, the effect of these intervals of biofilm formation and the interactions among the cells were evaluated. Biofilms from cultures were collected and analyzed for cell viability (CFU/mL), biofilm biomass, and total protein dosage. Data were analyzed using Mann-Whitney test (α = 5%). In addition, co-culture biofilms were analyzed using fluorescence microscopy. RESULTS: C. albicans growth did not change due to the presence of S. salivarius. Besides, co-culture biofilms showed a significant difference in the number of viable cells between 24 and 72 h of biofilm development (p < 0.05). The highest biofilm biomass and protein dosage were observed in co-cultures at 72 h of biofilm development. Fluorescence microscopy showed that co-cultures biofilms at 24 h have limited number of pseudo-hyphal and hyphae cells of C. albicans. At 72 h, these types of cells have increased. S. salivarius in both stages of development was present in some clusters surrounded by C. albicans. CONCLUSIONS: Co-cultivation of C. albicans with S. salivarius in biofilms developed on titanium surfaces, under lower oxygen levels, did not affect fungus growth. In addition, S. salivarius did not hind C. albicans virulence. These findings suggest that the use of S. salivarius as a probiotic would be ineffective in peri-implant disease treatment.

Assuntos

Candida albicans , Titânio , Biofilmes , Humanos , Hifas , Streptococcus salivarius

RESUMO

This study aims to evaluate the salivary parameters and cariogenic microbiota of pediatric oncological patients and their correlation with severe oral mucositis (SOM). A preliminary longitudinal study included patients in the age range from 4 to 18 years (n = 26), with diagnosis of primary cancer, who were followed up before and after time intervals of two, five, and ten weeks of induction chemotherapy. Oral mucosa examinations were performed by means of the modified Oral Assessment Guide (OAG) by calibrated examiners (κ > 0.70). Saliva analysis (unstimulated saliva flow (USF), clinical saliva viscosity (CSV), and pH) and microbiological (total Streptococcus (TS) and Streptococcus of the mutans group (SMG)) tests were performed using unstimulated saliva. The data were analyzed by the Wilcoxon and Spearman Correlation tests (α = 5%). The patients were predominantly of the female sex (n = 15; 57.7%), adolescents (n = 15; 57.7%), and patients with hematological tumors (n = 21; 80.8%). SOM was more frequent in the tenth week (n = 7; 28.6%). The values of USF, CSV, pH, TS, and SMG were not changed by the institution of chemotherapy (p > 0.05). These values were correlated with SOM and the time, TS and SMG, and CSV and SMG. The salivary and microbiological parameters investigated did not influence the severity of oral mucositis in the pediatric patients oncological..