Evaluation of brushing efficiency in reducing oral microbiota in mechanically ventilated patients admitted to an intensive care unit.

Background: Patients admitted to the Intensive Care Unit (ICU) are at greater risk of developing nosocomial infections due to their investigations, treatment and changes in the immune system. One of the most prevalent nosocomial infections is respiratory tract infection, such as hospital acquired pneumonia and ventilator-associated pneumonia (VAP). The bacteria commonly found in the oral cavity in the hospital environment are Streptococcus viridians, Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus spp., and Klebsiella pneumoniae. There is a need to test and define appropriate standard protocols for oral hygiene in patients undergoing mechanical ventilation in ICUs through the intervention of a dental specialist, preventing the proliferation of microorganisms into the respiratory tract, thus reducing hospitalization time, the use of antibiotics, and increased morbidity/mortality. Objective: This study aimed to evaluate the effectiveness of dental brushing in the reduction of the pathogenic buccal microbiota associated with mechanical ventilation in patients admitted to the Evangelical Hospital from Londrina, Paraná, Brazil. Methodology: The sample consisted of 90 patients (of both sexes), mean age of 65 years, under mechanical ventilation by orotracheal tube and tracheostomized patients, without suspected or confirmed diagnosis of pneumonia. Patients were randomized ∗∗∗. Results: Results showed that oral hygiene using a toothbrush by suction, with chlorhexidine gel 0.12% (Group B), was more effective than conventional hygiene using gauze soaked with chlorhexidine 0.12% (Group A) in reducing pathogenic buccal microbiota. Conclusions: There was a reduction of the pathogenic buccal microbiota in mechanically ventilated patients receiving oral hygiene using a toothbrush by suction with chlorhexidine gel 0.12% (Group B).

Production of IgY against iron permease Ftr1 from Candida albicans and evaluation of its antifungal activity using Galleria mellonella as a model of systemic infection.

Candida albicans is one of the leading pathological agents of mucosal and deep tissue infections. Considering that the variety of antifungals is restricted and that toxicity limits their use, immunotherapies against pathogenic fungi have been viewed as alternatives with reduced adverse effects. In this context, C. albicans has a protein used to capture iron from the environment and the host, known as the high-affinity iron permease Ftr1. This protein may be a new target of action for novel antifungal therapies, as it influences the virulence of this yeast. Thus, the aim of the present study was to produce and conduct the biological characterization of IgY antibodies against C. albicans Ftr1. Immunization of laying hens with an Ftr1-derived peptide resulted in IgY antibodies extracted from egg yolks capable of binding to the antigen with high affinity (avidity index = 66.6 ± 0.3%). These antibodies reduced the growth and even eliminated C. albicans under iron restriction, a favorable condition for the expression of Ftr1. This also occurred with a mutant strain that does not produce Ftr1 in the presence of iron, a circumstance in which the protein analog of iron permease, Ftr2, is expressed. Furthermore, the survival of G. mellonella larvae infected with C. albicans and treated with the antibodies was 90% higher than the control group, which did not receive treatment (p < 0.0001). Therefore, our data suggest that IgY antibodies against Ftr1 from C. albicans can inhibit yeast propagation by blocking iron uptake.

Antifungal Combination of Ethyl Acetate Extract of Poincianella pluviosa (DC.) L. P. Queiros Stem Bark With Amphotericin B in Cryptococcus neoformans.

Cryptococcus neoformans is the leading cause of cryptococcosis, an invasive and potentially fatal infectious disease. Therapeutic failures are due to the increase in antifungal resistance, the adverse effects of drugs, and the unavailability of therapeutic regimens in low-income countries, which limit the treatment of cryptococcosis, increasing the morbidity and mortality associated with these infections. Thus, new antifungal drugs and innovative strategies for the cryptococcosis treatment are urgently needed. The aim of the present study was to evaluate the effect of ethyl acetate fraction (EAF) of Poincianella pluviosa stem bark on planktonic and biofilm mode of growth of C. neoformans. Furthermore, the interaction between the EAF and amphotericin B (AmB) was evaluated in vitro and in Galleria mellonella infection model. Minimal inhibitory concentrations (MICs) of EAF ranged from 125.0 to >1,000.0 µg/ml and >1,000.0 µg/ml for planktonic and sessile cells, respectively. The combination between EAF and AmB exhibited a synergistic fungicidal activity toward C. neoformans, with a fractional inhibitory concentration index (FICI) ranging from 0.03 to 0.06 and 0.08 to 0.28 for planktonic and sessile cells, respectively. Microscopy analyses of planktonic C. neoformans cells treated with EAF, alone or combined with AmB, revealed morphological and ultrastructural alterations, including loss of integrity of the cell wall and cell membrane detachment, suggesting leakage of intracellular content, reduction of capsule size, and presence of vacuoles. Moreover, EAF alone or combined with AmB prolonged the survival rate of C. neoformans-infected G. mellonella larvae. These findings indicate that P. pluviosa may be an important source of new compounds that can be used as a fungus-specific adjuvant for the treatment of cryptococcosis.

Pravastatin and Simvastatin Pretreatment in Combination with Pyrimethamine and Sulfadiazine Reduces Infection Process of Toxoplasma gondii Tachyzoites (RH Strain) in HeLa Cells.

PURPOSE: Toxoplasma gondii is a protozoan from phylum Apicomplexa, which causes the toxoplasmosis infection; this one exhibits an apicoplast organelle which assists in the metabolism of isoprenoids and other pivotal mediators for the parasite survival. Statins are drugs that inhibit cholesterol synthesis, blocking the conversion of the substrate HMG-CoA to mevalonate, thus preventing the initial processes of the biosynthesis of these precursors, both in humans and parasite. Our goal was to verify whether the Toxoplasma gondii (RH strain) tachyzoites form pretreated with pravastatin and simvastatin in association with pyrimethamine and sulfadiazine at low concentrations could affect the infection processes, suggesting direct action on protozoa intracellular proliferation through the inhibition of isoprenoids in the parasite's apicoplast. METHODS: To have the adhesion, infection, and parasite proliferation during experimental infection investigated, HeLa cells (105) were subjected to a 24-hour infection by T. gondii tachyzoites forms of RH strain (5 × 105) pretreated for 30 min with pravastatin and/or simvastatin combined or not with pyrimethamine and sulfadiazine. RESULTS: Combined with conventional drugs at low concentrations pravastatin and simvastatin inhibit the adhesion, invasion, and intracellular proliferation of T. gondii in HeLa cells which are similar to the positive control. CONCLUSION: Pravastatin and simvastatin in association with pyrimethamine and sulfadiazine at low concentrations can be regarded as a promising, effective alternative to toxoplasmosis treatment with reduced side effects.

Beneficial Effects of Ethyl-Cyanoacrylate Coating Against Candida Albicans Biofilm Formation.

The aim of this study was to verify whether modifications made in a hard chairside reline resin by an ethyl-cyanoacrylate adhesive, ECA (Super Bonder®, Loctite, Itapevi, SP, Brazil) would be able to inhibit or reduce Candida albicans biofilm formation on its surface, comparing to a commercial surface sealant (BisCover®, Bisco, Schaumburg, USA). Reline resin specimens were fabricated and randomly divided into 6 groups (n=8): CG (control group), no surface treatment; ECA1, ECA coating on the surface before sterilization; ECA2, ECA coating after sterilization; ECA3, ECA incorporated in the resin bulk; DPE1, BisCover® coating before sterilization; DPE2, BisCover® coating after sterilization. Specimens were inoculated with C. albicans SC5314 (1x107 cells/mL) and incubated for 24 h. Then, the biofilm were stained with LIVE/DEAD® BaclightTM L7007 Kit and analyzed by Confocal Laser Scanning Microscopy. The images were evaluated by bioImageL® v.2.0 software and total biovolume (µm3), viable cells (%), and covered area (%) were calculated. Data were statistically analyzed by Kruskal-Wallis and Dunn tests (p<0.05). Results showed that ECA-coated groups presented better results, reducing C. albicans biofilm formation. Acquired images revealed that these groups (ECA1 and ECA2) presented a reduced number of cells, mostly in yeast form (less pathogenic), while the other groups presented higher number of cells, mostly in hyphae form (more pathogenic). Based on these findings, a beneficial effect of Super Bonder® coating reline resins surface could be demonstrated, suggesting a promising way to prevent fungal biofilm formation on dentures.

Toxicological findings about an anticancer fraction with casearins described by traditional and alternative techniques as support to the Brazilian Unified Health System (SUS).

ETHNOPHARMACOLOGICAL RELEVANCE: Extracts, essential oils and molecules from Casearia sylvestris have popularly shown pharmacological actions against chronic diseases, as anxiety, inflammation, cancer and dyslipidemia. In the context of antitumoral therapy, we investigated in vitro, ex vivo and in vivo toxicological changes induced by a Fraction with Casearins (FC) and its component Casearin X isolated from C. sylvestris on animal and vegetal cells, and upon invertebrates and mammals. MATERIAL AND METHODS: Cytotoxicity was carried out using normal lines and absorbance and flow cytometry techniques, Artemia salina nauplii, Danio rerio embryos and meristematic cells from Allium cepa roots. Acute and 30 days-mice analysis were done by behavioral, hematological and histological investigations and DNA/chromosomal damages detected by alkaline Cometa and micronucleus assays. RESULTS: FC was cytotoxic against lung and fibroblasts cells and caused DNA breaks, loss of integrity and mitochondrial depolarization on ex vivo human leukocytes. It revealed 24 h-LC50 values of 48.8 and 36.7 µg/mL on A. salina nauplii and D. rerio embryos, reduced mitotic index of A. cepa roots, leading to cell cycle arrest at metaphase and anaphase and micronuclei. FC showed i.p. and oral LD50 values of 80.9 and 267.1 mg/kg body weight. Subacute i.p. injections induced loss of weight, swelling of hepatocytes and tubules, tubular and glomerular hemorrhage, microvesicular steatosis, lung inflammatory infiltration, augment of GPT, decrease of albumin, alkaline phosphatase, glucose, erythrocytes, and lymphocytes, and neutrophilia (p > 0.05). FC-treated animals at 10 mg/kg/day i.p. caused micronuclei in bone marrow and DNA strand breaks in peripheral leukocytes. CONCLUSIONS: This research postulated suggestive side effects after use of FC-related drugs, demonstrating FC as antiproliferative and genotoxic on mammal and meristematic cells, including human leukocytes, teratogenicity upon zebrafish embryos, myelosuppression, clastogenicity, and morphological and biochemical markers indicating liver as main target for FC-induced systemic toxicity.

Beneficial effects of ethyl-cyanoacrylate coating against candida albicans biofilm formation

Abstract The aim of this study was to verify whether modifications made in a hard chairside reline resin by an ethyl-cyanoacrylate adhesive, ECA (Super Bonder®, Loctite, Itapevi, SP, Brazil) would be able to inhibit or reduce Candida albicans biofilm formation on its surface, comparing to a commercial surface sealant (BisCover®, Bisco, Schaumburg, USA). Reline resin specimens were fabricated and randomly divided into 6 groups (n=8): CG (control group), no surface treatment; ECA1, ECA coating on the surface before sterilization; ECA2, ECA coating after sterilization; ECA3, ECA incorporated in the resin bulk; DPE1, BisCover® coating before sterilization; DPE2, BisCover® coating after sterilization. Specimens were inoculated with C. albicans SC5314 (1x107 cells/mL) and incubated for 24 h. Then, the biofilm were stained with LIVE/DEAD® BaclightTM L7007 Kit and analyzed by Confocal Laser Scanning Microscopy. The images were evaluated by bioImageL® v.2.0 software and total biovolume (µm3), viable cells (%), and covered area (%) were calculated. Data were statistically analyzed by Kruskal-Wallis and Dunn tests (p<0.05). Results showed that ECA-coated groups presented better results, reducing C. albicans biofilm formation. Acquired images revealed that these groups (ECA1 and ECA2) presented a reduced number of cells, mostly in yeast form (less pathogenic), while the other groups presented higher number of cells, mostly in hyphae form (more pathogenic). Based on these findings, a beneficial effect of Super Bonder® coating reline resins surface could be demonstrated, suggesting a promising way to prevent fungal biofilm formation on dentures.

Resumo O objetivo deste estudo foi verificar se as modificações feitas com o adesivo etil cianoacrilato, ECA (Super Bonder ®, Loctite, Itapevi, SP, Brasil) sobre as resinas acrílicas para reembasamento, poderiam inibir ou reduzir a formação de biofilmes de C.albicans sobre sua superfície quando comparado com um selante de superfície comercial (BisCover®, Bisco, Schaumburg, EUA). Amostras de resina acrílica para reembasamento foram fabricadas e divididas aleatoriamente em 6 grupos (n=8): CG (grupo controle), sem tratamento superficial; ECA1, revestimento de ECA na superfície antes da esterilização; ECA2, revestimento de ECA após esterilização; ECA3, ECA incorporado no volume da resina; DPE1, revestimento de BisCover® antes da esterilização; DPE2, revestimento de BisCover® após esterilização. Os espécimes foram inoculados com C. albicans SC5314 (1x107 células/mL) e incubados durante 24 h. Seguidamente, o biofilme foi corado com LIVE/DEAD® BaclightTM L7007 Kit e analisado no microscópio confocal de varredura a laser. As imagens foram avaliadas pelo software bioImageL® v.2.0, no qual foram calculados o biovolume total (μm3), as células viáveis (%) e a área coberta (%). Os dados foram analisados estatisticamente pelos testes de Kruskal-Wallis e Dunn (p<0,05). Os resultados mostraram que os grupos revestidos com ECA apresentaram os melhores resultados, reduzindo a formação do biofilme de C. albicans. As imagens adquiridas revelaram que esses grupos (ECA1 e ECA2) apresentaram um número reduzido de células, principalmente na forma de levedura (menos patogênico), enquanto os outros grupos apresentaram um maior número de células, principalmente na forma de hifas (mais patogênicas). Com base nessas descobertas, encontra-se um efeito benéfico na aplicação do adesivo ECA sobre as superfícies das resinas acrílicas para reembasamento, sugerindo assim uma nova alternativa de prevenir a formação de biofilme fúngico em próteses dentárias.

Caffeic acid has antipromastigote activity by apoptosis-like process; and anti-amastigote by TNF-α/ROS/NO production and decreased of iron availability.

BACKGROUND: Leishmaniasis is a disease caused by protozoan parasites of the Leishmania genus whose current treatment has high cost, highly toxic, and difficult administration, which makes it very important to find alternative natural compounds of high efficiency and low cost. PURPOSE: This study assessed the in vitro effect of caffeic acid (CA) on promastigotes and L. amazonensis-infected macrophages. METHODS: Evaluation of the in vitro leishmanicidal activity of CA against promastigotes and L. amazonensis infected peritoneal macrophages, as well its microbicide mechanisms. RESULTS: CA 12.5-100 µg/ml were able to inhibit promastigotes proliferation at all tested periods. The IC50, 12.5 µg/ml, also altered promastigote cell morphology and cell volume accompanied by loss of mitochondrial integrity, increase in reactive oxygen species (ROS) production, phosphatidylserine exposure, and loss of plasma membrane integrity - characterizing the apoptosis-like process. Moreover, CA reduced the percentage of infected macrophages and the number of amastigotes per macrophages increasing TNF-α, ROS, NO and reducing IL-10 levels as well as iron availability. CONCLUSION: CA showed in vitro antipromastigote and antiamostigote by increasing oxidant and inflammatory response important to eliminate the parasite.

Antifungal activity of silver nanoparticles and simvastatin against toxigenic species of Aspergillus.

Aspergillus spp. are ubiquitous fungi that grow on stored grains. Some species produce toxins that can harm human and animal health, leading to hepato- and nephrotoxicity, immunosuppression and carcinogenicity. Major fungicides used to prevent fungal growth may be toxic to humans and their repeated use over time increases levels of resistance by microorganisms. Nanotechnology is an emerging field that allows use of antimicrobial compounds in a more efficient manner. In this study, was evaluated the antifungal activity of biogenic silver nanoparticles (AgNPs, synthesized by fungi) and simvastatin (SIM, a semi-synthetic drug), alone and in combination against three toxigenic species belonging to the genera Aspergillus section Flavi (Aspergillus flavus, Aspergillus nomius and Aspergillus. parasiticus) and two of section Circumdati (Aspergillus ochraceus and Aspergillus melleus). SIM exhibited a MIC50 of 78 µg/mL against species of Section Flavi and a MIC50 of 19.5 µg/mL against species of Section Circumdati. The MIC50 of AgNPs against Aspergillus flavus, Aspergillus nomius and Aspergillus parasiticus was 8 µg/mL, while the MIC50 was 4 µg/mL against Aspergillus melleus and Aspergillus ochraceus. Checkerboard assay showed that these compounds, used alone and in combination, have synergistic and additive effects against toxicogenic species of Aspergillus. Analysis by SEM gives an idea of the effect of SIM and AgNPs alone and in combination on spore germination and vegetative growth. Ultrastructural analysis revealed that spore germination was prevented, or aberrant hyphae were formed with multilateral branches upon treatment with SIM and AgNPs. These results reveal potential benefits of using combination of AgNPs and SIM to control fungal growth.

Oral Hygiene of Patients with Cancer in the Intensive Care Unit / Higiene Bucal de Pacientes com Câncer em Unidade de Terapia Intensiva

Dental care in Intensive Care Units - ICU, plays an important role in maintaining the health and well-being of critically ill patients. Although infection is a frequent manifestation in Intensive Care Unit (ICU) patients, the risk of infection by the oral cavity should also be considered. The immune response of this patient may be compromised, and consequently latent infections may intensify. The mouth is considered an ideal microbial incubator because of its characteristic of pH, presence of nutrients and hard surfaces. The relationship between periodontal disease and systemic conditions, including lung infections, is being explored. This study had the purpose of evaluating the odontology conditions in hospitalized patients with cancer in an intensive care unit at the Cancer Hospital of Londrina - Paraná, Brasil, quantifying the oral microbiota and evaluating bacterial resistance. Inclusion criteria involved critical patients of both sexes, two male and two female, ranging from 40 to 80 years old, submitted to mechanical endotracheal breathing. The presence of visible biofilm and xerostomia were the most prevalent. The results obtained are three patients who presented Klebsiella pneumoniae producer of Carbapenemase, due to the oral hygiene deficiency in patients hospitalized in the ICU, which are responsible for major systemic complications, increasing hospitalization time.(AU).

O atendimento odontológico nas Unidades de Terapia Intensiva - UTI, tem papel importante na manutenção da saúde e bem-estar dos pacientes criticamente doentes. Embora a infecção seja uma manifestação frequente em pacientes de Unidade de Terapia Intensiva (UTI), o risco de infecção pela cavidade bucal também deve ser considerado. A resposta imune desse paciente pode ser comprometida e consequentemente infecções latentes podem intensificar. A boca é considerada uma incubadora microbiana ideal devido à sua característica de pH, presença de nutrientes e superfícies duras. A relação entre doença periodontal e condições sistêmicas, incluindo infecções pulmonares, está sendo explorada. Este estudo teve a finalidade de avaliar as condições odontológicas em pacientes com câncer internados em unidade de terapia intensiva do Hospital do Câncer de Londrina estado do Paraná, Brasil, quantificando a microbiota bucal e avaliando a resistência bacteriana. Os critérios de Inclusão envolveram pacientes críticos de ambos sexos, dois masculinos e dois femininos com idade variando dos 40 aos 80 anos, submetidos à respiração mecânica endotraqueal. A presença de biofilme visível e xerostomia foram a alteração mais prevalente. Nos resultados obtidos encontrou-se três pacientes que apresentaram Klebsiella pneumoniae produtoras de Carbapenemase, pela deficiência de higienização bucal nos pacientes internados na UTI, que são responsáveis por grandes complicações sistêmicas, aumentando o tempo de internamento.(AU).

Candidíase Orofaríngea em Pacientes Submetidos a Radioterapia para Câncer de Cabeça e Pescoço: Revisão de Literatura / Oropharyngeal Candidiasis in Patients Undergoing Radiotherapy for Head and Neck Cancer: Literature Review

Candidiasis is closely related to patients undergoing head and neck radiotherapy due to the immunosuppressive state, induced xerostomia, mucositis and difficulties in establishing adequate oral hygiene. Therefore, the aim of this study was to discuss the relationship between candidal infections and the radiotherapy of the head and neck region, based on available scientific literature. In order to identify the studies included or considered in this study, a search strategy was carried out for the following databases: SCOPUS, Web of Science and PubMed. Inclusion criteria were publications that addressed key words: Candida spp. of the oral cavity and head and neck cancer. Therefore, this work exposes the necessity for studies relating candidal infections with radiotherapy treatment of the head and neck region. However, it is possible suggest that colonization and infection by Candida spp. can be increased by radiotherapy. Additionally, it can be suggested that patients irradiated at the head and neck region should be periodically investigated for the presence of pathogenic yeasts in the oral cavity, followed by greater care with oral hygiene and nutrition.(AU).

A candidíase está intimamente relacionada com pacientes submetidos a radioterapia de cabeça e pescoço devido ao estado imunossupressor, xerostomia induzida, mucosite e dificuldades no estabelecimento de higiene bucal adequada. Portanto, o objetivo deste estudo foi discutir a relação entre infecções por Candida spp. e a radioterapia da região da cabeça e pescoço, com base na literatura científica disponível. Para identificar os estudos incluídos ou considerados neste estudo, foi realizada uma estratégia de busca para os seguintes bancos de dados: SCOPUS, Web of Science e PubMed. Os critérios de inclusão foram publicações que abordavam as palavras-chave: Candida spp. da cavidade oral e câncer de cabeça e pescoço. Desta forma, este trabalho expõe a necessidade de estudos relacionados às infecções por Candida spp. com tratamento de radioterapia da região da cabeça e pescoço. No entanto, podemos sugerir que a colonização e a infecção por Candida spp. pode ser aumentada por radioterapia. Além disso, pode-se sugerir que os pacientes irradiados na região da cabeça e pescoço devem ser investigados periodicamente quanto à presença de leveduras patogênicas na cavidade bucal, seguido de maiores cuidados com higiene bucal e nutrição. (AU).

Métodos alternativos para a detecção de pirogênios em produtos e ambientes sujeitos a Vigilância Sanitária: avanços e perspectivas no Brasil a partir do reconhecimento internacional do Teste de Ativação de Monócitos / Alternative methods for the detection of pyrogens in products and environment subject to public health surveillance: advances and perspectives in Brazil based on the international recognition of the Monocyte Activation Test

Introduction: The detection of pyrogens is essential for the quality control of injectable products. The Rabbit Pyrogen Test remains widely used, despite the existence of alternative methods such as the Monocyte Activation Test (MAT). Objective: To review the use of alternative methods for pyrogen testing, pointing out advances and perspectives from the recognition of MAT by the European pharmacopoeia and its acceptance for regulatory purposes in Brazil. Method: A search was performed on the PubMed and BVS databases, with further classification, categorization by topic and critical analysis of the results. Results: Twenty-four papers were identified, addressing topics such as applications of MAT, its validation and comparisons with in vivo tests. MAT presented better results when compared to other tests, both in the evaluation of biological products and in the detection of non-endotoxin pyrogens. Limitations to diffusion include difficulties in obtaining whole human blood as a source of monocytes, for which several alternatives have been proposed. Conclusions: MAT is a promising method, with application in safety evaluation of new technologies. Its application in Brazil depends on a national implementation policy, which might include greater integration between BraCVAM, Concea and RENAMA in search for its recognition for regulatory purposes.

Introdução: A detecção de pirogênios é imprescindível no controle da qualidade de produtos injetáveis. O Teste de Pirogênio em coelhos ainda tem larga aplicação, apesar da existência de métodos alternativos como o Teste de Ativação de Monócitos (MAT). Objetivo: Revisar o uso dos métodos alternativos no teste de pirogênio, apontando avanços e perspectivas a partir do reconhecimento do MAT pela Farmacopeia Europeia e sua aceitação para fins regulatórios no Brasil. Método: Uma busca foi realizada nas bases PubMed e BVS, com posterior classificação, categorização por assuntos e análise crítica dos resultados. Resultados: Foram identificados 24 trabalhos, abordando temas como as aplicações do MAT, sua validação e comparação com testes in vivo. O MAT apresentou melhores resultados quando comparado a outros testes, tanto na avaliação de produtos biológicos como na detecção de pirogênios não-endotoxinas. Limitações para sua difusão incluem a dificuldade de obtenção de sangue total humano como fonte de monócitos, para o qual diversas alternativas têm sido propostas. Conclusões: O MAT se mostra um método promissor, com aplicação na avaliação da segurança de novas tecnologias. Sua aplicação no Brasil depende de uma política nacional de implantação, que inclua maior Integração entre BraCVAM, Concea e RENAMA na busca por seu reconhecimento para fins regulatórios.

In Vitro Evaluation of the Remineralizing Potential and Antimicrobial Activity of a Cariostatic Agent with Silver Nanoparticles.

Cariostatic treatment has been shown to successfully arrest caries. However, it blackens the carious tooth structure. This study evaluated the effects of an experimental cariostatic agent with silver nanoparticles (Ag-Nano) using microhardness (MH) and microbiological tests. The cariostatic agents tested were: Saforide®, Cariestop®, Ancarie® and Ag-Nano. Sixty-six samples from deciduous enamel were submitted to initial (after pH cycling to obtain initial caries-like lesion) and final (after cariostatic application) MH testing and %MH values were calculated. After longitudinal sectioning, internal (I) MH was evaluated. Strains of Streptococcus mutans, Escherichia coli, and Enterococcus faecalis in brain-heart infusion culture were treated with the cariostatic agents. Agar diffusion tests (ADTs) were performed and minimum inhibitory concentrations were determined. The statistical tests used were: Kruskal-Wallis and Dunn (%MD; ADT; MIC) and ANOVA followed by Tukey's test (I-MH) (p<0.05). The %MH of Saforide® was significantly greater than that of Ag-Nano (p<0.05). Internal MH showed progressive improvement in the enamel remineralization for all cariostatic tested. In ADTs showed greater inhibition of S. mutans, E. faecalis, and E. coli by Saforide® than by Ancarie® and Ag-Nano. Ag-Nano was able to inhibit 100% microorganism growth at a lower concentration than required for the other agents. It was concluded that Ag-Nano treatment promoted remineralization of deciduous tooth enamel with initial caries-like lesion and bactericidal activity.

In Vitro Evaluation of the Remineralizing Potential and Antimicrobial Activity of a Cariostatic Agent with Silver Nanoparticles

Abstract Cariostatic treatment has been shown to successfully arrest caries. However, it blackens the carious tooth structure. This study evaluated the effects of an experimental cariostatic agent with silver nanoparticles (Ag-Nano) using microhardness (MH) and microbiological tests. The cariostatic agents tested were: Saforide®, Cariestop®, Ancarie® and Ag-Nano. Sixty-six samples from deciduous enamel were submitted to initial (after pH cycling to obtain initial caries-like lesion) and final (after cariostatic application) MH testing and %MH values were calculated. After longitudinal sectioning, internal (I) MH was evaluated. Strains of Streptococcus mutans, Escherichia coli, and Enterococcus faecalis in brain-heart infusion culture were treated with the cariostatic agents. Agar diffusion tests (ADTs) were performed and minimum inhibitory concentrations were determined. The statistical tests used were: Kruskal-Wallis and Dunn (%MD; ADT; MIC) and ANOVA followed by Tukey's test (I-MH) (p<0.05). The %MH of Saforide® was significantly greater than that of Ag-Nano (p<0.05). Internal MH showed progressive improvement in the enamel remineralization for all cariostatic tested. In ADTs showed greater inhibition of S. mutans, E. faecalis, and E. coli by Saforide® than by Ancarie® and Ag-Nano. Ag-Nano was able to inhibit 100% microorganism growth at a lower concentration than required for the other agents. It was concluded that Ag-Nano treatment promoted remineralization of deciduous tooth enamel with initial caries-like lesion and bactericidal activity.

Resumo O tratamento com cariostático tem demostrado sucesso na paralização da cárie. No entanto, causa escurecimento da estrutura dental cariada. Este estudo avaliou os efeitos de um agente cariostático experimental com nanopartículas de prata (Ag-Nano) através de microdureza (MD) e testes microbiológicos. Os cariostáticos testados foram: Saforide®, Cariestop®, Ancarie® e Ag-Nano. Sessenta e seis amostras de esmalte decíduo foram submetidos a MD inicial (após ciclagem de pH para obtenção da lesão de cárie inicial) e final (após aplicação dos cariostáticos), e os valores da porcentagem (%) de MD foram calculados. Após secção longitudinal, a MD interna (I) foi avaliada. Cepas de Streptococcus mutans, Escherichia coli e E. faecalis foram cultivados em ágar infusão de cérebro e coração (BHI) e submetidos aos cariostáticos testados. Além disso, foram realizados teste de difusão em ágar (TDA) e avaliação da concentração mínima inibitória (CIM) dos cariostáticos. Os testes estatísticos usados foram: Kruskall-Wallis e Dunn (%MD; TDA; CIM) e ANOVA seguido de teste de Tukey (MD-I) (p<0.05). A %MD do Saforide® foi significativamente maior do que a de Ag-Nano (p<0,05). A MD interna apresentou melhora progressiva na remineralização do esmalte para todos os cariostático testados. Os resultados do TDA mostraram que S. mutans, E. faecalis e E. coli sofreram maior inibição pelo Saforide® (p<0,05), em relação ao Ancarie® e Ag-Nano. No entanto, para o teste de CIM o Ag-Nano foi capaz de inibir 100% dos microorganismos, em menor concentração do que os demais cariostaticos. Conclui-se que, o tratamento Ag-Nano foi capaz de promover remineralização do esmalte dental decíduo com lesão de cárie inicial e apresentou atividade bactericida.

Avidity as a criterion for diagnosis of human strongyloidiasis increases specificity of IgG ELISA.

This study evaluates the inclusion of the IgG avidity index in ELISA to detect anti-Strongyloides stercoralis IgG. The ELISA index revealed 70% of specificity. With the inclusion of screening AI, specificity increased to 80%. IgG avidity complemented traditional IgG ELISA by eliminating some of the suspected or false positive cases.

Activity of rosuvastatin in tachyzoites of Toxoplasma gondii (RH strain) in HeLa cells.

Due to the toxicity of conventional medication in toxoplasmosis, some drugs are being studied for treating this infection, such as statins, especially rosuvastatin compound, which is efficient in inhibiting the initial isoprenoid biosynthesis processes in humans and the parasite. The goal of this study was to assess the activity of rosuvastatin in HeLa cells infected with the RH strain of T. gondii. In the experiment, HeLa cells (1 × 105) were infected with tachyzoites of T. gondii (5 × 105). After the experimental infection, we assessed the number of infected cells and the amount of intracellular tachyzoites. In addition, culture supernatants were collected to determine the amount of cytokines by cytometric bead array. We observed that there was no cytotoxicity in the concentrations tested in this cell line. The effect of rosuvastatin showed a significant reduction in both the number of infected cells and the proliferation index of the intracellular parasite, when compared with the conventional treatment combining sulfadiazine and pyrimethamine for toxoplasmosis. There were also reduced levels of cytokines IL-6 and IL-17. Therefore, it was concluded that rosuvastatin exhibited antiproliferative activity. The data presented are significant to promote further studies and the search for alternative treatment for toxoplasmosis.

A Inserção da Odontologia em Unidades de Terapia Intensiva / The Insertion of Dentistry in Intensive Care Units

A Odontologia hospitalar vem adquirindo importância no cenário da equipe multidisciplinar de saúde para manter a qualidade de vida dos pacientes. Contudo, a atuação do cirurgião-dentista nos hospitais possui certa deficiência, mesmo sabendo que é imprescindível a higiene bucal para excluir doenças e manter a normalidade na cavidade bucal. Os pacientes internados em Unidade de Terapia Intensiva - UTI, frequentemente, apresentam baixa imunidade, apresentando como fatores contribuintes a hipossalivação, a utilização de antibióticos e a ausência de higiene bucal. É importante ressaltar que a cavidade bucal abriga quase a metade da microbiota do corpo humano e é considerada uma incubadora microbiana ideal devido a suas características de temperatura, de umidade, de pH, de tensão de oxigênio e presença de nutrientes. Para o presente artigo de revisão foi usado o método de buscas, em revisão integrativa, utilizando-se as bases de dados Pubmed, Scopus, Web of Science, e SciELO. Os artigos usados foram selecionados por critérios segundo o tema odontologia aplicada à Unidade de Terapia Intensiva. O objetivo desse estudo é analisar a importância de uma equipe odontológica para o atendimento integral de pacientes internados em UTI na redução da disseminação de infecções a partir da cavidade bucal. Conclui-se que é necessário maior reconhecimento da participação Odontológica na equipe multidisciplinar de saúde, sendo de fundamental importância para a prevenção das infecções nas UTI, especialmente, de pneumonias, colaborando para reduzir quadros de septicemia grave. Nas buscas realizadas destaca-se a Pubmed por ser mais abrangente que as outras bases de dados, obtendo um total de 800 publicações. (AU)

Hospital Dentistry has been gaining importance in the scenery of multidisciplinary health team to maintain the patients' life quality patients. However, the dentist's role in hospitals presentssome deficiency, knowing that oral hygiene is essential to exclude diseases and maintain normalcy in the oral cavity. Patients in intensive care unit (ICU) often have low immunity, presenting as contributing factors hyposalivation, the use of antibiotics and the lack of oral hygiene. It important to highlight that the oral cavity is home to almost half of the microbiota of the human body and is considered an ideal microbial incubator due to its characteristics of temperature, moisture, pH, oxygen tension and presence of nutrients. For the present review, it was used the method searches in integrative review using databases Pubmed, Scopus, Web of Science, e SciELO. Used articles were selected according to the subject and criteria of dentistry applied to the Intensive Care Unit. The aim of this study is to analyze the importance of a dentistry team for the comprehensive care of ICU patients in reducing the spread of infection from the oral cavity. It was concluded that it is necessary a better recognition of Dentistry participation in multidisciplinary health team, being of fundamental importance for the prevention of infections in ICUs, especially pneumonia, helping reduce severe sepsis clinical signs. In the searches carried out PUBMED stands out because it is more comprehensive than the other databases, obtaining a total of 800 publications. (AU)

Pravastatin and simvastatin inhibit the adhesion, replication and proliferation of Toxoplasma gondii (RH strain) in HeLa cells.

The conventional treatment for toxoplasmosis with pyrimethamine and sulfadiazine shows toxic effects to the host, and it is therefore necessary to search for new drugs. Some studies suggest the use of statins, which inhibit cholesterol synthesis in humans and also the initial processes of isoprenoid biosynthesis in the parasite. Thus, the objective of this study was to evaluate the activity of the statins pravastatin and simvastatin in HeLa cells infected in vitro with the RH strain of T. gondii. HeLa cells (1×105) were infected with T. gondii tachyzoites (5×105) following two different treatment protocols. In the first protocol, T. gondii tachyzoites were pretreated with pravastatin (50 and 100µg/mL) and simvastatin (1.56 and 3.125µg/mL) for 30min prior to infection. In the second, HeLa cells were first infected (5×105) with tachyzoites and subsequently treated with pravastatin and simvastatin for 24h at the concentrations noted above. Initially, we evaluated the cytotoxicity of drugs by the MTT assay, number of tachyzoites adhered to cells, number of infected cells, and viability of tachyzoites by trypan blue exclusion. The supernatant of the cell cultures was collected post-treatment for determination of the pattern of Th1/Th2/Th17 cytokines by cytometric bead array. There was no cytotoxicity to HeLa cells with 50 and 100µg/mL pravastatin and 1.56 and 3.125µg/mL simvastatin. There was no change in the viability of tachyzoites that received pretreatment. Regarding the pre- and post-treatment of the cells with pravastatin and simvastatin alone, there was a reduction in adhesion, invasion and proliferation of cells to T. gondii. As for the production of cytokines, we found that IL-6 and IL-17 were significantly reduced in cells infected with T. gondii and treated with pravastatin and simvastatin, when compared to control. Based on these results, we can infer that pravastatin and simvastatin alone possess antiproliferative effects on tachyzoites forms of T. gondii, giving these drugs new therapeutic uses.

Galleria mellonella hemocytes: A novel phagocytic assay for Leishmania (Viannia) braziliensis.

Galleria mellonella is an excellent invertebrate model for the study of diseases that involve interactions with cells from the innate immune system, since they have an innate immune system capable of recognizing the pathogens. Here we present for the first time, an alternative model for an in vitro phagocytic assay using hemocytes of G. mellonella larvae to study infection by Leishmania (Viannia) braziliensis. We showed that the insect phagocytic cells were able to engulf promastigotes. Furthermore, this infective form differentiated into the amastigote form inside those cells. However, the cells in this model seem resistant to the parasite, since amastigotes were depleted after 24h and NO levels were maintained after infection. Our model opens an avenue of possibilities for new investigations regarding other Leishmania species, mechanisms of invasion and evasion, receptors involved, release of signaling molecules and, above all, it is a novel infection model using invertebrate animals.

Expression of Secreted Aspartyl Proteinases in an Experimental Model of Candida albicans-Associated Denture Stomatitis.

PURPOSE: Candida albicans is known to produce secreted aspartyl proteinases (SAPs) to aid adhesion, invasion, and host tissue destruction. SAPs may contribute to denture stomatitis (DS) pathogenesis. The aim of this study was to develop an in vivo experimental model for Candida-associated DS that allows the analysis of SAP2, SAP5, and SAP9 expression by C. albicans from biofilm induced on the denture surface. MATERIALS AND METHODS: Thirty-five male Wistar rats were divided into three groups: control, denture, and denture/Candida group. The last two groups remained with dentures for 2, 4, and 6 days, with or without induced biofilm. SAP expression was concomitant with leukocyte counts as well as clinical and histological changes shown by animal palate. RESULTS: The signs observed at 4 days in the denture/Candida group were clinically closer to the Candida-associated DS, showing a significant increase of neutrophils and decrease of lymphocytes in peripheral blood, presence of inflammation signs on the palate similar to DS Newton type I, and fungal invasion in the epithelial layer. Accordingly, the denture/Candida group at 4 days presented the highest relative expression of all SAPs studied. CONCLUSION: The results showed a coincidence between SAP expression and clinical, microscopic, and blood data. Finally, the molecular findings were consistent with the virulence capacities of C. albicans from biofilm formed on the denture resin, which possibly allowed epithelial invasion by the fungus.