Cytotoxicity Comparison of a Calcium Silicate-Based Resin Cement versus Conventional Self-Adhesive Resin Cement and a Resin-Modified Glass Ionomer: Cell Viability Analysis

Abstract Objective: To compare the cytotoxicity level of a new calcium silicate-based resin cement (TheraCem) with two commonly used cements, including a conventional self-adhesive resin cement (Panavia SA) and a resinmodified glass ionomer cement (FujiCem2), on the human gingival fibroblast cells after 24 and 48 hours. Material and Methods: Twelve discs of each cement type were fabricated. The extract of cement disks was made by incubating them in the cell medium. Human gingival fibroblast cells were cultured and exposed to cement extracts for 24 h and 48 h. MTT assay was performed on extracts and optical density and cell viability rates were calculated by the spectrophotometer device at 570 nm. Data were analyzed using ANOVA and Tukey HSD tests. Results: The cell viability rates after 24 hours and 48 hours were as follows: TheraCem: 89.24% and 85.46%, Panavia SA: 49.51% and 46.57% and FujiCem2: 50.63% and 47.36%. TheraCem represented the highest cell viability rate. However, no significant difference was noted between Panavia SA and FujiCem2. Time had no significant effect on cell viability. Conclusion: TheraCem exhibited the best results among three tested cements and was considered non-toxic. Panavia SA and FujiCem2 were not significantly different regarding the cell viability rate. Time had no significant effect on the cytotoxicity level of cements (AU).

Hidrogel de quitosana com nanofibras de Policaprolactona (PCL) associado a extratos fitoterápicos no metabolismo celular e ação antimicrobiana: estudo in vitro / Evaluation of the chitosan hydrogel with PCL nanofibers associated with phytotherapeutic extracts in cellular and microbiological activity: in vitro study

O objetivo neste estudo foi produzir hidrogel de quitosana (CH) com PCL e fitoterápicos para uso preventivo de úlcera de pressão. Os hidrogéis de CH foram produzidos com glicerofosfato (GP) e com xantana (X), associados ao PCL e foram caracterizados por estereomicroscopio, intumescimento, molhabilidade e MEV. Posteriormente foram submetidos ao teste de viabilidade (MTT) com fibroblastos HFF-1 e queratinócitos HaCat. O hidrogel que apresentou melhor resultado foi escolhido para continuar na pesquisa. Posteriormente, extratos de Pfaffia panculata K, Juglans regia L, Rosmarinus officinalis L, Zingiber officinale, Própolis e Hamamelis foram colocados em contato com cepas de Staphylococcus aureus (S.a) (ATCC 6538), Streptococcus pyogenes (S.p) (ATCC 19615), Staphylococcus epidermidis (S.e) (ATCC 12228), Pseudomonas aeruginosa (P.a) (ATCC 15442), Escherichia coli (E.c) (ATCC 25922) e Klebsiella Pneumoniae (K.p) (ATCC 4352) na forma planctônica nos testes de CIM e CMM. Os dois melhores extratos fitoterápicos foram avaliados quanto ao sinergismo no teste checkerboard e posteriormente associados ao hidrogel anteriormente eleito. A seguir, o comportamento da HaCat e HFF-1 com os hidrogéis foi analisado por MTT, proteína total, ELISA, genotoxicidade e formação de biofilme monotípico com suspensões padronizadas (107 cel/mL) de S.a, S.e, S.p, P.a, E.c e K.p. Na caracterização e viabilidade o hidrogel CHX PCL apresentou os melhores resultados. Os extratos selecionados após CIM, CMM e checkerboard foram gengibre (G) e própolis (P). O extrato G se destacou na CIM com inibição de K. p e P. a. Os extratos de G e P demonstraram ação microbicida para K. p e P. a e somente o extrato P obteve ação microbicida para S. a na CMM. Houve ação aditiva dos extratos associados no checkerboard para S.p e ação aditiva e sinérgica para S. e. Os grupos de hidrogéis foram compostos por: quitosana xantana (CHX), CHX própolis (CHXP), CHX gengibre (CHXG) e CHX própolis e gengibre associados (CHXPG), todos associados ao PCL. Todos os hidrogéis demonstraram viabilidade celular acima de 70% do grupo controle, permitindo metabolismo celular observado na proteína total. Houve quantificação de IL-6 maior no grupo CHX nas duas linhagens de células enquanto a quantificação de IL-10 não exibiu diferença estatística entre os grupos. Todos os hidrogéis promoveram redução acentuada de biofilme de K.p e E.c. Os grupos CHX, CHXP e CHXG reduziram biofilme de S.e. O grupo CHXG reduziu biofilme de S.p. Para S.a e P.a o grupo CHXPG foi mais eficaz reduzindo biofilme. Concluímos que os hidrogéis apresentaram resultados satisfatórios e promissores, trazendo inovação por associação de biopolímeros e associação de extratos fitoterápicos pouco estudados. Os resultados positivos justificam a continuidade dos estudos com esse biomaterial(AU)

The aim of this study was to produce chitosan hydrogel (CH) with PCL and herbal medicines for preventive use of pressure ulcers. The CH hydrogels were produced with glycerophosphate (GP) and xanthan (X), associated with PCL and were characterized by stereomicroscope, swelling, wettability and SEM. Subsequently, they were submitted to a viability test (MTT) with HFF-1 fibroblasts and HaCat keratinocytes. The hydrogel that presented the best result was chosen to continue the research. Subsequently, extracts of Pfaffia panculata K, Juglans regia L, Rosmarinus officinalis L, Zingiber officinale, Propolis and Hamamelis were placed in contact with strains of Staphylococcus aureus (Sa) (ATCC 6538), Streptococcus pyogenes (Sp) (ATCC 19615), epidermidis (Se) (ATCC 12228), Pseudomonas aeruginosa (Pa) (ATCC 15442), Escherichia coli (Ec) (ATCC 25922) and Klebsiella Pneumoniae (Kp) (ATCC 4352) in planktonic form in CIM and CMM tests. The two best herbal extracts were evaluated for synergism in the checkerboard test and subsequently associated with the previously elected hydrogel. Next, the behavior of HaCat and HFF-1 with hydrogels was analyzed by MTT, total protein, ELISA, genotoxicity and monotypic biofilm formation with standardized suspensions (107 cel / mL) of Sa, Se, Sp, Pa, Ec and Kp In the characterization and viability the CHX PCL hydrogel presented the best results. The extracts selected after MIC, CMM and checkerboard were ginger (G) and propolis (P). The G extract stood out in the MIC with inhibition of K. p and P. a. The extracts of G and P showed microbicidal action for K. p and P. a and only the extract P obtained microbicidal action for S. a in CMM. There was an additive action of the associated extracts on the checkerboard for S.p and an additive and synergistic action for S. e. The hydrogel groups were composed of: xanthan chitosan (CHX), CHX propolis (CHXP), CHX ginger (CHXG) and CHX propolis and ginger associated (CHXPG), all associated with PCL. All hydrogels demonstrated cell viability above 70% of the control group, allowing cellular metabolism observed in the total protein. There was a greater quantification of IL-6 in the CHX group in the two cell lines while the quantification of IL-10 did not show statistical difference between the groups. All hydrogels promoted a marked reduction in the biofilm of K.p and E.c. The CHX, CHXP and CHXG groups reduced S.e biofilm. The CHXG group reduced S.p. For S.a and P.a, the CHXPG group was more effective in reducing biofilm. We conclude that the hydrogels presented satisfactory and promising results, bringing innovation through association of biopolymers and association of phytotherapic extracts little studied. The positive results justify the continuity of studies with this biomaterial(AU)

Salmonella enterica serovar Typhi plasmid pR ST98 -mediated inhibition of autophagy promotes bacterial survival in infected fibroblasts.

pR ST98 is a chimeric plasmid isolated from Salmonella enterica serovar typhi (S. typhi) and mediates both drug-resistance and virulence of S. typhi. Autophagy has been recently reported as an important component of the innate immune response against intracellular pathogen. In this study, we investigated the effect of pR ST98 on cellular autophagy, apoptosis and bacterial survival in infected fibroblasts. S. typhi strain ST 8 carrying pR ST98 , Salmonella typhimurium strain SR-11 carrying a 100 Kb virulent plasmid, and avirulent S. typhi strain ST 10 without plasmid were tested in this experiment. Results showed that embryonic fibroblasts infected with ST 8 containing pR ST98 had decreased autophagy accompanied by increased bacterial survival and apoptosis. Further study showed that autophagy inducer rapamycin reversed pR ST98 -mediated inhibition of autophagy and reduced apoptosis in infected fibroblasts. Our data indicate that pR ST98 can inhibit autophagy, thus facilitating S. typhi survival and promoting apoptosis of host cells. This study contributes to understanding the underlying mechanism of pR ST98 -mediated virulence in S. typhi.

Citotoxicidade de enxaguatório bucal em células fibroblásticas: avaliação de diferentes tempos / Cytotoxicity of oral mouthrinse in fibroblast cells: evaluation of different times

Este artigo tem por objetivo analisar a citotoxicidade de enxaguatório bucal em diferentes períodos de tempo. Avaliou-se o enxaguatório bucal (Cepacol Tradicional, Sanofi-Aventis, Suzano, Brasil) em diferentes tempos: 1, 15, 30, 45, 60 e 120 segundos quanto seu efeito citotóxico em fibroblastos gengivais L929. Utilizou-se 3 grupos controle: positivo (C+) detergente celular Tween 80, negativo (C-) PBS, e controle de célula (CC) em que as células não foram expostas a nenhum material. O ensaio de citotoxicidade foi realizado utilizando cultura celular de fibroblasto de camundongo (L929). Após contato do enxaguatório com as células, as mesmas foram colocadas em contato com o corante vital vermelho neutro utilizando-se a técnica dyeuptake. Os valores da quantidade de células viáveis foram submetidos à análise de variância (ANOVA) para determinar se havia diferenças estatísticas entre os grupos, e posteriormente ao teste de Tukey (p<0.05). Os resultados demonstraram que o enxaguatório apresentou citotoxicidade em todos os tempos avaliados. Essa citotoxicidade foi diretamente proporcional ao tempo de exposição à cultura de células. Houve diferença estatisticamente significante entre os grupos CC (Controle de células) e o grupo C (Cepacol) em todos os tempos avaliados (P<0.05). Concluindo que o enxaguatório Cepacol Tradicional foi citotóxico em todos os períodos de tempo avaliados.

The objective was to o evaluate the cytotoxicity of oral mouthrinse in different periods of time. The evaluation occurred to the oral mouthrinse (Traditional Cepacol, Sanofi-Aventis, Suzano, Brazil) at different times: 1, 15, 30, 45, 60 and 120 seconds as their cytotoxic effect on gingival fibroblasts L929. We used 3 control groups: positive (C +) cell detergent Tween 80, negative (C-) PBS, and control of cell (CC) where the cells were not exposed to any material. The cytotoxicity test was performed using the cell culture of mouse fibroblast (L929). After contact with the cells of the mouthrinse, they were placed in contact with the vital dye neutral red is used the technique (“dyeuptake”). The values of the quantity of viable cells, were subjected to analysis of variance (ANOVA) to determine whether there were statistical differences between groups, and then the Tukey test (p <0.05). The mouthrinse showed cytotoxicity at all times evaluated. This cytotoxicity was proportional to the time of exposure to culture cells. There was a statistically significant difference between groups CC (control cells) and group C (Cepacol) at all times (P <0.05). concluding that the traditional Cepacol mouthrinse was cytotoxic in all time periods evaluated.

Diagnóstico de diarrea por clostridium difficile: en busca de un enfoque clínico más eficiente / Clinical diagnosis of clostridium difficile diarrhea: searching a more efficient clinical view

Background: The clinical parameters for the suspicion of Clostridium difficile infections, namely the use of antimicrobials and diarrhea, have a low predictive value for the diagnosis. Aim: To search other clinical variables and determine a clinical prediction model for (Clostridium difficile diarrhea. Patients and methods: All patients to whom a Clostridium difficile study was requested, were prospectively studied during 5 months. Clinical variables of these patients were registered. The diagnosis of Clostridium difficile was done using the cytotoxicity test in fibroblast cultures. Results: Ninety two patients were analyzed and in 26, the diagnosis of Clostridium difficile was confirmed. A logistic regression model disclosed an age over 60 years old, the presence of mucus in the stools and a temperature over 37.8 ­C in the previous 24 h, as significant predictors of the infection. The correlation of the model, between the predicted probability and the observed condition, was 81.5 per cent. Conclusions: The presence of the clinical variables identified in this study are associated with a high probability of an infection by Clostridium difficile in patients with diarrhea and the recent use of antimicrobials

Deteccion de citomegalovirus mediante la tecnica de inmunoperoxidasa y aislamiento viral / Detection of citomegalovirus by immunoperoxidase technic and viral isolation

En el presente estudio se comparo la tecnica de inmunoperoxidasa para la deteccion de citomegalovirus (IPCMV) utilizando anticuerpos monoclonales que reconocen proteinas precoces virales con el metodo convencional de aislamiento viral en fibroblastos humanos. Un total de 150 muestras de orina fueron examinadas encontrando una sensibilidad de un 89.8 por ciento y una especificidad de 91.3 por ciento de la tecnica de IPCMV comparada con el aislamiento viral. Una de las ventajas que presento la IPCMV fue la rapidez con que fueron obtenidos los resultados (48 horas) mientras que el aislamiento viral fue como promedio 14 dias.