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1.
Rev. CEFAC ; 25(5): e6823, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1521543

RESUMEN

ABSTRACT Purpose: to assess the advancement in communicative intention and cognition in children with autism spectrum disorder after applying a personalized alternative communication method. Methods: patients had their communicative intention and cognition (Vineland-3) assessed before and after the intervention with 10 structured alternative communication sessions. The "Demystifying Alternative Communication" podcast was developed as supplementary material to this study. Student's t-test was used, setting the significance level at p < 0.05. Results: patients improved their communicative intention, with higher scores after the intervention, and no changes were found in relation to cognition. Conclusion: even though the patients' equivalent age was inferior to their real age in the communication subdomain assessment, they progressed in expressive communication, language, and writing.


RESUMO Objetivo: avaliar o avanço da intenção comunicativa e da cognição em crianças com Transtorno do Espectro Autista após a aplicação de metodologia personalizada de comunicação alternativa. Métodos: foram realizadas dez sessões estruturadas de comunicação alternativa e os pacientes foram avaliados antes e após a intervenção quanto a intenção comunicativa e cognição (Vineland-3). Como material suplementar deste trabalho, foi elaborado o podcast "Desmistificando a Comunicação Alternativa". Foi utilizado teste t-Student com o p <0,05 onsiderado significante. Resultados: os pacientes apresentaram melhoras quanto à intenção comunicativa, demonstrando maiores escores após a realização da intervenção. Conclusão: apesar de os pacientes apresentarem uma idade equivalente inferior à idade real na avaliação do subdomínio da comunicação, estes demonstraram avanços quanto às variáveis de comunicação expressiva, linguagem e escrita.

2.
Blood Coagul Fibrinolysis ; 32(6): 411-417, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34397450

RESUMEN

Leukocyte-platelet rich fibrin (PRF) is an autologous biomaterial formed by platelets, cytokines, growth factors and cells imprisoned on a fibrin mesh, produced according to Choukroun's protocol. The aim of the present article was to report the use of PRF, associated with a bone substitute, on the regenerative treatment of a large bone defect resulting from the enucleation of a paradental cyst involving the posterior mandible. The treatment resulted in the maintenance of the bone volume, and radiographic evaluation showed new bone formation after 40 days, suggesting an osteogenic and osteoinductive effect. Also, the current literature was reviewed.


Asunto(s)
Sustitutos de Huesos/uso terapéutico , Quistes/terapia , Leucocitos/metabolismo , Traumatismos Mandibulares/terapia , Fibrina Rica en Plaquetas/metabolismo , Adolescente , Regeneración Ósea , Sustitutos de Huesos/metabolismo , Femenino , Humanos , Traumatismos Mandibulares/metabolismo , Traumatismos Mandibulares/patología
3.
Vet Parasitol Reg Stud Reports ; 23: 100523, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33678378

RESUMEN

The cattle tick Rhipicephalus microplus is a significant problem for livestock, causing losses of billions of dollars per year. This work aimed to determine the chemical composition of essential oils obtained from Laurus nobilis and Copaifera officinalis and evaluate activity against engorged R. microplus females. Chemical composition analyzed by GC-MS revealed the presence of 39 components accounting for 95.38% of the oil in L. nobilis, the most abundant being 1,8-cineol (25.7%), trans-sabinene-hydrate (20.8%), and α-terpinil acetate (15.0%). Chemical analysis of C. officinalis oil identified 25 components corresponding to 80.5% of the total constituents, where the major compounds were ß-caryophyllene (21.1%), caryophyllene oxide (10.7%), and α-trans-bergamotene (9.3%). Adult immersion test (AIT) showed that L. nobilis essential oil at 5% or 10% caused 80.5% mortality of engorged females after 24 h and reached 96.9% and 100% mortality on the third day after treatment, respectively. While the essential oil from C. officinalis caused 84.7% mortality after six days at 10% and at 5%, achieved approximately 100% mortality rate at the end of the experiment (day 15). Both essential oils and the combination significantly inhibited egg-laying; however, the combination treatment showed higher effectiveness than the isolated oils at 2.5%. A possible synergic action of L. nobilis and C. officinalis against the cattle tick R. microplus is therefore suggested. The present work introduces a potential alternative for the development of a formulation environment-friendly (green pesticide) used to control cattle tick infestations.


Asunto(s)
Acaricidas , Aceites Volátiles , Aceites de Plantas , Rhipicephalus , Acaricidas/farmacología , Animales , Femenino , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Rhipicephalus/efectos de los fármacos
4.
J Conserv Dent ; 23(2): 196-200, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33384495

RESUMEN

AIMS: This study determined the corrosion rate by mass loss caused by oral strains of sulphate-reducing bacteria (SRB) in Kerr endodontic files (KF), aiming the development of a biopharmaceutical that facilitates the removal of endodontic limb fragments from root canals. MATERIALS AND METHODS: Nine new KF were analyzed after immersion in the modified Postgate E culture medium inoculated with Desulfovibrio desulfuricans oral (84 days), Desulfovibrio fairfieldensis in the consortium (84 days) and environmental D. desulfuricans (119 days). RESULTS: Optical microscopy revealed corrosion suggestive areas in all files submitted to immersion in SRB cultures, presenting a statistical difference (P < 0.05) between the samples environmental D. desulfuricans and KF control and between oral D. desulfuricans and KF control. Epifluorescence microscopy revealed an active SRB biofilm over the entire metal surface of the KF, as evidenced by the SYTO® 9 fluorophore. CONCLUSION: SRB were capable of promoting biocorrosion in Kerr type endodontic files, but with low rate.

5.
Pharmaceutics ; 11(5)2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-31052360

RESUMEN

Cutaneous leishmaniasis (CL) is a parasitic disease characterized by progressive skin sores. Currently, treatments for CL are limited to parenteral administration of the drug, which presents severe adverse effects and low cure rates. Therefore, this study aimed to develop poly(vinyl-alcohol) (PVA) hydrogels containing Amphotericin B (AmB) intended for topical treatment of CL. Hydrogels were evaluated in vitro for their potential to eliminate promastigote forms of Leishmania spp., to prevent secondary infections, to maintain appropriate healing conditions, and to offer suitable biocompatibility. AmB was incorporated into the system in its non-crystalline state, allowing it to swell more and faster than the system without the drug. Furthermore, the AmB release profile showed a continuous and controlled behavior following Higuchi´s kinetic model. AmB-loaded-PVA-hydrogels (PVA-AmB) also showed efficient antifungal and leishmanicidal activity, no cytotoxic potential for VERO cells, microbial impermeability and water vapor permeability compatible with the healthy skin's physiological needs. Indeed, these results revealed the potential of PVA-AmB to prevent secondary infections and to maintain a favorable environment for the healing process. Hence, these results suggest that PVA-AmB could be a suitable and efficient new therapeutic approach for the topical treatment of CL.

6.
Arq. odontol ; 55: 1-12, jan.-dez. 2019. ilus, tab
Artículo en Portugués | LILACS, BBO - Odontología | ID: biblio-1052824

RESUMEN

Objetivo: Avaliar as alterações químicas presentes na superfície metálica de limas endodônticas fraturadas em canais radiculares, in vitro, após a inoculação intrarradicular de culturas de BRS de três cepas microbianas, Desulfovibrio desulfuricans (uma cepa oral e outra ambiental) e Desulfovibrio fairfieldensis. Métodos: foram analisadas 5 limas kerr #90, sendo uma Lima Kerr nova, sem tratamento, e as outras 4 limas fraturadas dentro de canais radiculares in vitro, com posterior inoculação de Desulfovibrio desulfuricans, cepa oral e ambiental, e Desulfovibrio fairfieldensis e um grupo controle sem inoculação bacteriana, por 477 dias. Os grupos foram analisados no modo EDS (Espectrometria de Energia Dispersiva de Raios-x) do microscópio eletrônico de varredura (FEI-Inspect-S50). Resultados:A presença do S, Cl e O foram relacionados ao processo biocorrosivo, assim como a redução dos elementos de liga nesta área. Conclusão:As análises no modo EDS demonstraram biocorrosão ao longo da superfície metálica das limas quando empregado o biofármaco BACCOR, nas três diferentes cepas empregadas, indicada pela redução dos elementos formadores da liga metálica, Fe, Ni e Cr, com a associação da presença de elementos indicadores de biocorrosão como O, Cl e S. (AU)


Aim:To evaluate the chemical alterations present on the metallic surface of root canal fractured endodontic files in vitro after the intraradicular inoculation of BRS cultures of three microbial strains, Desulfovibrio desulfuricans (one oral and one environmental strain), and Desulfovibrio fairfieldensis. Methods: Five kerr #90 files were analyzed, one new untreated Kerr file and the other 4 files fractured within root canals in vitro, with a subsequent inoculation of Desulfovibrio desulfuricans (oral and environmental strains), and Desulfovibrio fairfieldensis, as well as a control group without bacterial inoculation for 477 days. The groups were analyzed using the scanning electron microscope (FEI-Inspect-S50) EDS (X-ray Dispersive Energy Spectrometry) mode. Results:The presence of S, Cl, and O were related to the biocorrosive process, as well as the reduction of alloying elements in this area. Conclusion: The EDS mode analysis showed biocorrosion along the metallic surface of the files when the BACCOR biopharmaceutical was used in the three different strains employed in this study, indicated by the reduction of the alloying elements ­ Fe, Ni, and Cr ­ with the association of the presence of indicator elements of biocorrosion, such as O, Cl, and S. (AU)


Asunto(s)
Productos Biológicos , Corrosión , Medios de Cultivo , Aleaciones Dentales , Instrumentos Dentales , Desulfovibrio desulfuricans , Cavidad Pulpar , Desulfovibrio , Técnicas In Vitro , Endodoncia
7.
Mem Inst Oswaldo Cruz ; 113(10): e180311, 2018 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-30304087

RESUMEN

BACKGROUND: Scedosporium apiospermum is a ubiquitous, emerging and multidrug-resistant fungal pathogen with still rather unknown virulence mechanisms. OBJECTIVES/METHODS: The cellular basis of the in vitro interaction between fungi and host cells/tissues is the determinant factor for the development of a successful in vivo infection. Herein, we evaluated the interaction of S. apiospermum conidia with lung epithelial (A549), lung fibroblast (MRC-5) and RAW 264.7 macrophages by light and scanning/transmission electron microscopy. FINDINGS: After 4 h of fungi-host cell contact, the percentage of infected mammalian cells and the number of fungi per infected cell was measured by light microscopy, and the following association indexes were calculated for A549, MRC-5 and macrophage cells: 73.2 ± 25.9, 69.7 ± 22.5 and 59.7 ± 11.1, respectively. Both conidia and germinated conidia were regularly observed interacting with the evaluated cells, with a higher prevalence of non-germinated conidia. Interestingly, nests of germinated conidia were evidenced at the surface of lung cells by scanning electron microscopy. Some germination projections and hyphae were seen penetrating/evading the mammalian cells. Furthermore, internalised conidia were seen within vacuoles as visualised by transmission electron microscopy. MAIN CONCLUSIONS: The present study contributes to a better understanding of S. apiospermum pathogenesis by demonstrating the first steps of the infection process of this opportunistic fungus.


Asunto(s)
Células Epiteliales/microbiología , Pulmón/microbiología , Macrófagos/microbiología , Scedosporium/ultraestructura , Esporas Fúngicas/ultraestructura , Células Epiteliales/ultraestructura , Humanos , Pulmón/ultraestructura , Macrófagos/ultraestructura , Microscopía Electrónica de Rastreo , Scedosporium/fisiología , Esporas Fúngicas/fisiología
8.
J Comput Biol ; 25(12): 1285-1300, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30251882

RESUMEN

In vitro experiments were conducted in this work to analyze the proliferation of tumor (DU-145) and normal (macrophage RAW 264.7) cells under the influence of a chemotherapeutic drug (doxorubicin). Approximate Bayesian Computation (ABC) was used to select among four competing models to represent the number of cells and to estimate the model parameters, based on the experimental data. For one case, the selected model was validated in a replicated experiment, through the solution of a state estimation problem with a particle filter algorithm, thus demonstrating the robustness of the ABC procedure used in this work.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Doxorrubicina/farmacología , Modelos Teóricos , Neoplasias de la Próstata/patología , Animales , Línea Celular Tumoral , Resistencia a Antineoplásicos , Humanos , Masculino , Ratones , Células RAW 264.7
9.
Int J Dent ; 2018: 8303450, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29861730

RESUMEN

AIM: This study describes the biofilm formation and the corrosive capacity of sulfate-reducing bacteria (SRB) on the metallic structure of used endodontic files. METHODS: Sulfate-reducing bacteria (SRB) (Desulfovibrio desulfuricans oral and Desulfovibrio fairfieldensis or D. desulfuricans environmental) were inoculated into the culture media (Postgate C culture medium or modified Postgate E culture medium). The biocorrosive potential of these bacteria will be an important component of a biopharmaceutical under development called BACCOR. Afterwards, four used endodontic files (UEFs) were separately inoculated into a specific culture media for 445 days at 30°C in an incubator. The four UEFs were placed in a scanning electron microscope (SEM) and analyzed by the energy-dispersive X-ray spectrometry (EDS). RESULTS: The confocal laser scanning microscopic images indicate the presence of biofilm in the four samples. The SEM and SEM-EDS revealed the presence of rough, irregular structures adhering along the metallic surface of the used endodontic files, suggesting a mature calcified biofilm with a high concentration of Ca, P, C, and S. CONCLUSION: The formation of SRB biofilms on used endodontic files shows characteristics that may contribute to the biocorrosion of these files, and the results may also provide complementary data for a biopharmaceutical, which is still under development to assist in the removal of fractured endodontic files inside root channels.

10.
Med Chem ; 14(3): 304-310, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28676004

RESUMEN

BACKGROUND: Over the last few years, fungal infections have emerged as a worrisome global public health problem. Candidiasis is a disease caused by Candida species and has been a problem worldwide mainly for immunosuppressed patients. Lately, the resistant strains and side effects have been reported as important issues for treating Candidiasis, which have to be solved by identifying new drugs. OBJECTIVE: The goal of this work was to synthesize a series of 1,3-benzoxathiol-2-one derivatives, XYbenzo[ d][1,3]oxathiol-2-ones, and evaluate their antifungal activity against five Candida species. METHODS: In vitro antifungal screening test and minimum inhibitory concentration determination were performed according to CLSI protocols using ketoconazole as the reference drug. The cytotoxicity of the most active compounds was evaluated by hemolysis and MTT (Vero cells) assays. RESULTS: Compounds 2 (XY = 6-hydroxy-5-nitro, MIC = 4-32 µg/mL) and 7 (XY = 6-acetoxy-5-nitro, MIC =16-64 µg/mL) showed good results when compared with current antifungals in CLSI values (MIC = 0.04-250 µg/mL). These compounds exhibited a safer cytotoxicity as well as a lower hemolytic profile than ketoconazole. CONCLUSION: Overall, the in vitro results pointed to the potential of compounds 2 and 7 as new antifungal prototypes to be further explored.


Asunto(s)
Antifúngicos/farmacología , Compuestos Heterocíclicos con 2 Anillos/farmacología , Lactonas/farmacología , Antifúngicos/síntesis química , Antifúngicos/química , Antifúngicos/toxicidad , Candida/efectos de los fármacos , Cristalografía por Rayos X , Compuestos Heterocíclicos con 2 Anillos/síntesis química , Compuestos Heterocíclicos con 2 Anillos/química , Compuestos Heterocíclicos con 2 Anillos/toxicidad , Lactonas/síntesis química , Lactonas/química , Lactonas/toxicidad , Pruebas de Sensibilidad Microbiana , Estructura Molecular
11.
Mem. Inst. Oswaldo Cruz ; 113(10): e180311, 2018. graf
Artículo en Inglés | LILACS | ID: biblio-955107

RESUMEN

BACKGROUND Scedosporium apiospermum is a ubiquitous, emerging and multidrug-resistant fungal pathogen with still rather unknown virulence mechanisms. OBJECTIVES/METHODS The cellular basis of the in vitro interaction between fungi and host cells/tissues is the determinant factor for the development of a successful in vivo infection. Herein, we evaluated the interaction of S. apiospermum conidia with lung epithelial (A549), lung fibroblast (MRC-5) and RAW 264.7 macrophages by light and scanning/transmission electron microscopy. FINDINGS After 4 h of fungi-host cell contact, the percentage of infected mammalian cells and the number of fungi per infected cell was measured by light microscopy, and the following association indexes were calculated for A549, MRC-5 and macrophage cells: 73.2 ± 25.9, 69.7 ± 22.5 and 59.7 ± 11.1, respectively. Both conidia and germinated conidia were regularly observed interacting with the evaluated cells, with a higher prevalence of non-germinated conidia. Interestingly, nests of germinated conidia were evidenced at the surface of lung cells by scanning electron microscopy. Some germination projections and hyphae were seen penetrating/evading the mammalian cells. Furthermore, internalised conidia were seen within vacuoles as visualised by transmission electron microscopy. MAIN CONCLUSIONS The present study contributes to a better understanding of S. apiospermum pathogenesis by demonstrating the first steps of the infection process of this opportunistic fungus.


Asunto(s)
Humanos , Scedosporium , Macrófagos , Carcinoma de Pulmón de Células no Pequeñas , Factor C1 de la Célula Huésped
12.
Biochem Res Int ; 2017: 5342947, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29123924

RESUMEN

The present research aimed to study the chemical composition and acaricidal activity of Citrus limonum and Piper nigrum essential oils against the cattle tick Rhipicephalus microplus. GC-MS analysis of C. limonum essential oil showed limonene (50.3%), ß-pinene (14.4%), and γ-terpinene (11.7%) as the major components; P. nigrum oil was mainly composed of ß-caryophyllene (26.2%), σ-ocymene (5.8%), and α-pinene (5.5%). Acaricide activity was evaluated at concentrations of 2.5, 5.0, and 10.0% (v/v) of each plant oil, as well as 1 : 1 combination of both oils (5% : 5%, 2.5% : 2.5%, and 1.25% : 1.25% each), by immersing engorged R. microplus females for one minute. The LC90 of oils from C. limonum, P. nigrum, and the combination were 4.9%, 14.8%, and 5.1%, respectively. C. limonum essential oil caused 100% mortality of engorged females at the highest concentration (10%). P. nigrum essential oil inhibited egg-laying by up to 96% in a concentration-dependent manner, suggesting it reduces tick fecundity. When combined, the oils presented toxicity as to C. limonum oil alone, but with stronger inhibition of oviposition (5% : 5%), indicating a possible additive effect against R. microplus. The present data provide support for further investigation of novel natural products to control bovine tick infestations.

13.
Regul Toxicol Pharmacol ; 91: 1-8, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28970106

RESUMEN

The application of in silico methods is increasing on toxicological risk prediction for human and environmental health. This work aimed to evaluate the performance of three in silico freeware models (OSIRIS v.2.0, LAZAR, and Toxtree) on the prediction of carcinogenicity and mutagenicity of thirty-eight volatile organic compounds (VOC) related to chemical risk assessment for occupational exposure. Theoretical data were compared with assessments available in international databases. Confusion matrices and ROC curves were used to evaluate the sensitivity, specificity, and accuracy of each model. All three models (OSIRIS, LAZAR and Toxtree) were able to identify VOC with a potential carcinogenicity or mutagenicity risk for humans, however presenting differences concerning the specificity, sensitivity, and accuracy. The best predictive performances were found for OSIRIS and LAZAR for carcinogenicity and OSIRIS for mutagenicity, as these softwares presented a combination of negative predictive power and lower risk of false positives (high specificity) for those endpoints. The heterogeneity of results found with different softwares reinforce the importance of using a combination of in silico models to occupational toxicological risk assessment.


Asunto(s)
Carcinógenos/toxicidad , Pruebas de Mutagenicidad/métodos , Mutágenos/toxicidad , Medición de Riesgo/métodos , Compuestos Orgánicos Volátiles/toxicidad , Simulación por Computador , Bases de Datos Factuales , Humanos , Modelos Biológicos , Mutagénesis/efectos de los fármacos , Exposición Profesional/efectos adversos , Sensibilidad y Especificidad , Programas Informáticos
14.
Anticancer Agents Med Chem ; 17(4): 483-490, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27481554

RESUMEN

Cancer incidence represents an important public health problem worldwide. Nuclear factor kappa B (NF- κB) transcription factor plays a pivotal role in the regulation of genes that control various responses in eukaryotic cells, including proliferation and survival, cytoskeletal remodeling, cellular adhesion and apoptosis. Extensive studies have demonstrated the contribution of NF-κB transcription in the promotion and progression of several hematological malignancies and solid tumors, in which NF-κB constitutive activation and/or overexpression are common clinical features. Moreover, triggering the NF-κB pathway is already considered one of the important mechanisms of resistance development to chemotherapy and radiotherapy, indicating that the inhibition of this signaling cascade is a promising approach to enhancing efficacy and preventing acquired resistance in cancer treatment. In this review, research efforts dedicated to the identification of novel NF-κB signaling pathway inhibitors as promising anticancer drug candidates are described.


Asunto(s)
Antineoplásicos/farmacología , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Neoplasias/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Animales , Antiinflamatorios no Esteroideos/farmacología , Antineoplásicos/química , Glucocorticoides/farmacología , Humanos , Quinasa I-kappa B/antagonistas & inhibidores , Neoplasias/genética , Neoplasias/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Ubiquitinación/efectos de los fármacos
15.
Dent Mater J ; 35(5): 762-768, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27725513

RESUMEN

This study assessed the cell viability of the inoculation vehicle of BACCOR (a combination of sulfate-reducing bacteria plus a culture media for bacteria), a biopharmaceutical product under development for dental use as aid in fractured endodontic file removal from the root canal. Different culture media for bacteria were evaluated: modified Postgate E (MCP-E mod), Modified Postgate E without Agar-agar (MCP-E w/Ag), Postgate C with Agar-agar (MCP-C Ag) and Postgate C without Agar-agar (MCP-C w/Ag). Cytotoxicity was quantified by the MTT test, exposing L929 and Vero cell lines to the vehicles over 24 h. The exposure of L929 cell line to MCP-E w/Ag resulted in biocompatibility (52% cell viability), while the exposure of the Vero kidney line revealed only MCP-E mod as cytotoxic. When diluted, all the vehicles showed biocompatibility with both cell lines. MCP-E w/Ag was the vehicle chosen for BACCOR, because of its biocompatibility with the cells used.


Asunto(s)
Supervivencia Celular , Endodoncia , Bacterias Reductoras del Azufre , Línea Celular , Medios de Cultivo , Sulfatos
16.
J Contemp Dent Pract ; 16(8): 665-73, 2015 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-26423503

RESUMEN

AIM: This study assessed the biocorrosive capacity of two bacteria: Desulfovibrio desulfuricans and Desulfovibrio fairfieldensis on endodontic files, as a preliminary step in the development of a biopharmaceutical, to facilitate the removal of endodontic file fragments from root canals. MATERIALS AND METHODS: In the first stage, the corrosive potential of the artificial saliva medium (ASM), modified Postgate E medium (MPEM), 2.5 % sodium hypochlorite (NaOCl) solution and white medium (WM), without the inoculation of bacteria was assessed by immersion assays. In the second stage, test samples were inoculated with the two species of sulphur-reducing bacteria (SRB) on ASM and modified artificial saliva medium (MASM). In the third stage, test samples were inoculated with the same species on MPEM, ASM and MASM. All test samples were viewed under an infinite focus Alicona microscope. RESULTS: No test sample became corroded when immersed only in media, without bacteria. With the exception of one test sample between those inoculated with bacteria in ASM and MASM, there was no evidence of corrosion. Fifty percent of the test samples demonstrated a greater intensity of biocorrosion when compared with the initial assays. CONCLUSION: Desulfovibrio desulfuricans and D. fairfieldensis are capable of promoting biocorrosion of the steel constituent of endodontic files. CLINICAL SIGNIFICANCE: This study describes the initial development of a biopharmaceutical to facilitate the removal of endodontic file fragments from root canals, which can be successfully implicated in endodontic therapy in order to avoiding parendodontic surgery or even tooth loss in such events.


Asunto(s)
Desulfovibrio/fisiología , Endodoncia/instrumentación , Preparación del Conducto Radicular/instrumentación , Bacterias Reductoras del Azufre/fisiología , Corrosión , Desulfovibrio/clasificación , Desulfovibrio/efectos de los fármacos , Endodoncia/métodos , Humanos , Preparación del Conducto Radicular/métodos , Bacterias Reductoras del Azufre/clasificación , Bacterias Reductoras del Azufre/efectos de los fármacos
17.
Mem Inst Oswaldo Cruz ; 109(7): 940-3, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25410999

RESUMEN

Endothelial dysfunction is a major component of the pathophysiology of septicaemic group B Streptococcus (GBS) infections. Although cytokines have been shown to activate human umbilical vein endothelial cells (HUVECs), the capacity of interferon (IFN)-γ to enhance the microbicidal activity of HUVECs against GBS has not been studied. We report that the viability of intracellular bacteria was reduced in HUVECs activated by IFN-γ. Enhanced fusion of lysosomes with bacteria-containing vacuoles was observed by acid phosphatase and the colocalisation of Rab-5, Rab-7 and lysosomal-associated membrane protein-1 with GBS in IFN-γ-activated HUVECs. IFN-γ resulted in an enhancement of the phagosome maturation process in HUVECs, improving the capacity to control the intracellular survival of GBS.


Asunto(s)
Antiinfecciosos/farmacología , Células Endoteliales de la Vena Umbilical Humana/microbiología , Interferón gamma/farmacología , Viabilidad Microbiana/efectos de los fármacos , Infecciones Estreptocócicas/tratamiento farmacológico , Streptococcus agalactiae/efectos de los fármacos , Fosfatasa Ácida/metabolismo , Adhesión Bacteriana/efectos de los fármacos , Endocitosis , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Lisosomas/efectos de los fármacos , Fagosomas/efectos de los fármacos , Cultivo Primario de Células , Infecciones Estreptocócicas/prevención & control , Análisis de Supervivencia
18.
Mem. Inst. Oswaldo Cruz ; 109(7): 940-943, 11/2014. graf
Artículo en Inglés | LILACS | ID: lil-728811

RESUMEN

Endothelial dysfunction is a major component of the pathophysiology of septicaemic group B Streptococcus (GBS) infections. Although cytokines have been shown to activate human umbilical vein endothelial cells (HUVECs), the capacity of interferon (IFN)-γ to enhance the microbicidal activity of HUVECs against GBS has not been studied. We report that the viability of intracellular bacteria was reduced in HUVECs activated by IFN-γ. Enhanced fusion of lysosomes with bacteria-containing vacuoles was observed by acid phosphatase and the colocalisation of Rab-5, Rab-7 and lysosomal-associated membrane protein-1 with GBS in IFN-γ-activated HUVECs. IFN-γ resulted in an enhancement of the phagosome maturation process in HUVECs, improving the capacity to control the intracellular survival of GBS.


Asunto(s)
Humanos , Antiinfecciosos/farmacología , Células Endoteliales de la Vena Umbilical Humana/microbiología , Interferón gamma/farmacología , Viabilidad Microbiana/efectos de los fármacos , Infecciones Estreptocócicas/tratamiento farmacológico , Streptococcus agalactiae/efectos de los fármacos , Fosfatasa Ácida/metabolismo , Adhesión Bacteriana/efectos de los fármacos , Endocitosis , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Lisosomas/efectos de los fármacos , Cultivo Primario de Células , Fagosomas/efectos de los fármacos , Análisis de Supervivencia , Infecciones Estreptocócicas/prevención & control
19.
Curr Microbiol ; 69(3): 357-64, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24807624

RESUMEN

Bacterial multiresistance is a health problem worldwide that demands new antimicrobials for treating bacterial-related infections. In this study, we evaluated the antimicrobial activity and the theoretical toxicology profile of N-substituted-phenylamino-5-methyl-1H-1,2,3-triazole-4-carbohydrazide derivatives against gram-positive and gram-negative bacteria clinical strains. On that purpose we determined the minimum inhibitory (MIC) and bactericidal (MBC) concentrations, the in vitro cytotoxicity, and in silico risk profiles, also comparing with antimicrobial agents of clinical use. Among the 16 derivatives analyzed, four nitrofurans (N-H-FUR-NO(2), N-Br-FUR-NO(2), N-F-FUR-NO(2), N-Cl-FUR-NO(2)) showed promising MIC and MBC values (MIC = MBC = 1-16 µg/mL). The experimental data revealed the potential of these derivatives, which were comparable to the current antimicrobials with similar bactericidal and bacteriostatic profiles. Therefore, these molecules may be feasible options to be explored for treating infections caused by multiresistant strains. Our in vitro and in silico toxicity reinforced these results as these derivatives presented low cytotoxicity against human macrophages and low theoretical risk profile for irritant and reproductive effects compared to the current antimicrobials (e.g., vancomycin and ciprofloxacin). The molecular modeling analysis also revealed positive values for their theoretical druglikeness and drugscore. The presence of a 5-nitro-2-furfur-2-yl group seems to be essential for the antimicrobial activity, which pointed these acylhydrazone derivatives as promising for designing more potent and safer compounds.


Asunto(s)
Antibacterianos/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Hidrazonas/farmacología , Infecciones Bacterianas/microbiología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Farmacorresistencia Bacteriana Múltiple , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Humanos , Macrófagos/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos
20.
Int J Nanomedicine ; 7: 5175-82, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23055729

RESUMEN

BACKGROUND: Dapsone is described as being active against Mycobacterium leprae, hence its role in the treatment of leprosy and related pathologies. Despite its therapeutic potential, the low solubility of dapsone in water results in low bioavailability and high microbial resistance. Nanoemulsions are pharmaceutical delivery systems derived from micellar solutions with a good capacity for improving absorption. The aim of this work was to develop and compare the permeability of a series of dapsone nanoemulsions in Caco-2 cell culture against that of effective permeability in the human body simulated using Gastroplus™ software. METHODS AND RESULTS: The release profiles of the dapsone nanoemulsions using different combinations of surfactants and cosolvent showed a higher dissolution rate in simulated gastric and enteric fluid than did the dispersed dapsone powder. The drug release kinetics were consistent with a Higuchi model. CONCLUSION: This comparison of dapsone permeability in Caco-2 cells with effective permeability in the human body simulated by Gastroplus showed a good correlation and indicates potential improvement in the biodisponibility of dapsone using this new system.


Asunto(s)
Dapsona/administración & dosificación , Dapsona/farmacocinética , Modelos Biológicos , Modelos Químicos , Nanocápsulas/química , Administración Oral , Antiinfecciosos/administración & dosificación , Antiinfecciosos/química , Disponibilidad Biológica , Células CACO-2 , Simulación por Computador , Dapsona/química , Difusión , Emulsiones/química , Humanos , Nanocápsulas/ultraestructura , Tamaño de la Partícula , Permeabilidad
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