Antibiofilm Activity and Mechanism of Action of the Disinfectant Chloramine T on Candida spp., and Its Toxicity against Human Cells.

We evaluated the antifungal and anti-biofilm activity, mechanism of action and cytotoxicity of chloramine T trihydrate (CAT) against Candida spp. The Minimum Inhibitory and Fungicidal Concentrations (MIC/MFC) of CAT were determined. Changes in CAT-treated C. albicans growth kinetics and micromorphology were evaluated, as well as the mechanism of action, and its effects on biofilm. Cytotoxicity was assessed by the hemolysis method. The data were analyzed by inferential statistics (p ≤ 0.05). CAT showed antifungal activity against all strains, with MIC values ranging between 1.38 and 5.54 mmol/L (MIC75%: 2.77 mmol/L). CAT demonstrated an immediate and sustained action on C. albicans growth kinetics, particularly at 2 × MIC. This compound likely acts on the cell wall and membrane permeability simultaneously and was found to cause changes in C. albicans micromorphology. Tha antibiofilm activity of CAT was similar to that of sodium hypochlorite (p > 0.05) against mature biofilms. CAT was more effective than NaOCl in reducing mature biofilm upon 1-min exposure at 2 × MIC (24 h) and 4 × MIC (48 h) (p < 0.05). Toxicological analysis revealed that CAT had hemolytic activity between 61 and 67.7% as compared to 100% by NaOCl. CAT has antifungal and anti-biofilm properties, probably acting on both cell wall and membrane permeability, and showed low toxicity in vitro.

Antifungal activity, mode of action and anti-biofilm effects of Laurus nobilis Linnaeus essential oil against Candida spp.

OBJECTIVE: The present study demonstrated the antifungal potential of the chemically characterized essential oil (EO) of Laurus nobilis L. (bay laurel) against Candida spp. biofilm adhesion and formation, and further established its mode of action on C. albicans. METHODS: L. nobilis EO was obtained and tested for its minimum inhibitory and fungicidal concentrations (MIC/MFC) against Candida spp., as well as for interaction with cell wall biosynthesis and membrane ionic permeability. Then we evaluated its effects on the adhesion, formation, and reduction of 48hC. albicans biofilms. The EO phytochemical profile was determined by gas chromatography coupled to mass spectrometry (GC/MS). RESULTS: The MIC and MFC values of the EO ranged from (250 to 500) µg/mL. The MIC values increased in the presence of sorbitol (osmotic protector) and ergosterol, which indicates that the EO may affect cell wall biosynthesis and membrane ionic permeability, respectively. At 2 MIC the EO disrupted initial adhesion of C. albicans biofilms (p<0.05) and affected biofilm formation with no difference compared to nystatin (p>0.05). When applied for 1min, every 8h, for 24h and 48h, the EO reduced the amount of C. albicans mature biofilm with no difference in relation to nystatin (p>0.05). The phytochemical analysis identified isoeugenol as the major compound (53.49%) in the sample. CONCLUSIONS: L. nobilis EO has antifungal activity probably due to monoterpenes and sesquiterpenes in its composition. This EO may affect cell wall biosynthesis and membrane permeability, and showed deleterious effects against C. albicans biofilms.

Antifungal activity and mode of action of thymol and its synergism with nystatin against Candida species involved with infections in the oral cavity: an in vitro study.

BACKGROUND: Limitations of antifungal agents used in the treatment of oral candidiasis, as the development of resistant strains, are known by the scientific community. In this context, the aim of this study was to evaluate the antifungal activity of thymol against Candida albicans, Candida tropicalis and Candida krusei strains and to determine its mode of action and synergistic effect when combined with the synthetic antifungal nystatin. METHODS: The minimum inhibitory concentration (MIC) was determined using a microdilution technique, and the minimum fungicidal concentration (MFC) was determined via subculture sowing. The mode of action of thymol was established by verifying fungal growth in the presence of sorbitol or ergosterol. The fractional inhibitory concentration index (FIC) was determined using the checkerboard method. RESULTS: Thymol presented an antifungal effect, with MICs of 39 µg/mL for C. albicans and C. krusei and 78 µg/mL for C. tropicalis. The results of the antifungal test remained unchanged in the presence of sorbitol; however, the MIC value of thymol against C. albicans increased eight times (from 39.0 to 312.5 µg/mL) in presence of exogenous ergosterol. The combination of thymol and nystatin reduced the MIC values of both products by 87.4%, generating an FIC index of 0.25. CONCLUSIONS: Thymol was found to have a fungicidal effect on Candida species and a synergistic effect when combined with nystatin.

Does scientific evidence for the use of natural products in the treatment of oral candidiasis exist? A systematic review.

In view of the limitations of antifungal agents used in the treatment of oral candidiasis and the wide variety of natural products that have been studied as treatment of this disease, this systematic literature review proposed to evaluate whether scientific evidence attesting to the efficacy of natural products in the treatment of this disease exists. A systematic search in PubMed, MEDLINE, SciELO, Lilacs, and Cochrane Library databases was accomplished using the associations among the keywords Candida albicans, phytotherapy, biological products, denture stomatitis, and oral candidiasis in both English and Portuguese. Four independent observers evaluated the methodological quality of the resulting articles. Three studies were included for detailed analysis and evaluated according to the analysis protocol based on the CONSORT (Consolidated Standards of Reporting Trials) 2010 statement. The tested products were different in all studies. Two studies mentioned random samples, but no study described the sample allocation. No study mentioned sample calculations, a prior pilot study, or examiner calibration, and only one trial reported sample losses. Differences between the tested products and the methodological designs among these studies did not allow the existence of scientific evidence related to the effectiveness of these products for the proposed subjects to be confirmed.

Fatores de Risco à Segurança doEnfermeiro na Unidade de TerapiaIntensiva de um Hospital Geral / Risk Factors to the Safety of Nurses Working In the Intensive Care Unit of a General Hospital

As unidades de terapia intensiva constituem locaisonde a enfermagem presta assistência qualificada a pacientesgraves. Objetivo: Identificar os fatores de riscos aos quaiso enfermeiro intensivista está exposto e que podem ocasionaracidentes de trabalho. Material e Métodos: Foi utilizada umaabordagem indutiva com procedimento comparativo eestatístico através da observação direta extensiva, utilizandoquestionários. A amostra foi composta por 15 enfermeirosatuantes há dois anos ou mais em um hospital de referênciade João Pessoa – PB. Dentre os itens avaliados nosquestionários, buscou-se caracterizar e avaliar as exigênciasdo contexto de trabalho e os riscos aos quais os enfermeirosestão expostos. Resultados: Verificou-se que 60% dossujeitos responderam que às vezes o ritmo de trabalho éexcessivo; 73,3% disseram que às vezes as condições detrabalho são precárias; 46,6% responderam quefrequentemente existe muito barulho no ambiente de trabalho;53,4% assinalaram que é bastante exigido ter controle dasemoções. Além disso, 86,7% dos participantes referiram tersentido três ou mais vezes dores no corpo e 46,6% referiramtrês ou mais episódios de estresse desencadeado peloconvívio com a dor, o sofrimento e a morte. Conclusão: Foramidentificados riscos biológicos, como acidentes comperfurocortantes e fluidos gerais de pacientes, riscos físicos,a exemplo de exposição à radiação e ruídos, riscos químicosdevido à exposição a substâncias como antissépticos,ergonômicos, associados a esforços repetidos entre outros,assim como risco ocupacional, remetendo principalmente aoritmo de trabalho excessivo...

Intensive care units (ICUs) are facilities wherethe nursing staff provides specialized care to critically-illpatients. Objective: To identify the risk factors that can causeaccidents in ICUs to which nurses are exposed. Materialand Methods: This study used an inductive approach, withcomparative statistical procedure, and extensive directobservation by means of a questionnaire. The sampleconsisted of 15 nurses who had been working for two yearsor more in a reference hospital located in Joao Pessoa, PB.Based on the topics covered in the questionnaire, we aimedto characterize and evaluate the requirements of the workingenvironment and the risks to which nurses are exposed.Results: A total of 60% of subjects reported that sometimesthe pace of work is excessive; 73.3% said that workingconditions are precarious; 46.6% reported that there is oftena lot of noise in the workplace; 53.4% indicated that they arestrongly required to have enough control of emotions. Inaddition, 86.7% of participants reported having felt bodyaches three or more times; and 46.6% reported three ormore episodes of stress caused by living with the pain,suffering and death. Conclusion: We identified biologicalhazards, such as accidents with needlestick and generalfluids of patients; physical risks, such as exposure toradiation and noise; chemical hazards, one of them due toexposure to substances such as antiseptics; ergonomicissues, associated with repeated efforts and others, as wellas occupational hazards, referring mainly to the excessivepace of work...

A Randomized Clinical Trial of Schinus terebinthifolius Mouthwash to Treat Biofilm-Induced Gingivitis.

Objectives. This study aimed to investigate the efficacy of a Schinus terebinthifolius (ST) mouthwash in reducing gingival inflammation levels (GI) and biofilm accumulation (BA) in children with gingivitis. Methods. This was a randomized, controlled, triple blind, and phase II clinical trial, with children aged 9-13 years (n = 27) presenting with biofilm-induced gingivitis. The sample was randomized into experimental (0.3125% ST, n = 14) and control (0.12% chlorhexidine/CHX, n = 13) groups. Products were masked as regards color, flavor and aroma. Intervention protocol consisted in supervised rinsing of 10 mL/day for 01 minute for 10 days. Gingival bleeding and simplified oral hygiene indexes were used to assess the efficacy variables, measured at baseline and after intervention by calibrated examiners. Data were statistically treated with paired t-test, unpaired t-test, and Wilcoxon and Mann-Whitney tests ( α = .05). Results. It was found that both ST and CHX were able to significantly reduce GI levels after 10 days (P < 0.001) and there was no significant difference between them (P > 0.05). CHX was the only product able to significantly reduce BA after 10 days when compared to baseline (P < 0.05). Conclusion. ST mouthwash showed significant anti-inflammatory activity (equivalent to CHX), but it was not able to reduce biofilm accumulation.

Atividade antibacteriana in vitro de fitoconstituintes sobre micorganismos do biofilme dentário / In vitro antibacterial activity of phytochemicals on dental biofilm microorganisms

Objetivo: Avaliar in vitro a atividade antimicrobiana docitronelol, linalol, timol e D-limoneno frente a Streptococcus mutans, S. salivarius e S. oralis. Materiale Métodos: Realizou-se um screening pela técnica de difusão em meio sólido. Discos de papel absorvente foram em bebidos com 30 μL da substância-teste e dispostos em placas dePetri contendo Ágar Müeller Hinton previamente semeadas com inóculo bacteriano. Após incubação por 24h a 37ºC, foi realizada a mensuração dos halos de inibição do crescimento bacteriano com auxílio de um paquímetro manual. A clorexidina2% foi utilizada como controle positivo. O estudo foi realizado em triplicata. Resultados: O citronelol obteve média do diâmetro dos halos, em milímetros (mm), para S. mutans, S.oralis e S. salivarius, respectivamente: 10.7, 10.0 e 9.8. Otimol, para a mesma sequência de microorganismos: 7.3, 7.3e 8.3 mm. O D-limoneno exibiu médias de 8.0, 6.7 e 6.0 mmpara S. mutans, S. oralis e S. salivarius, respectivamente.Mensurou-se médias dos halos de 8.0, 9.0 e 8.2 mm, para os mesmos microorganismos, quando testado o linalol. Aclorexidina, por sua vez, apresentou média dos diâmetros dos halos de 17 mm para S. mutans, 16.8 mm para S. oralis e19.7 mm para S. salivarius. Conclusão: Os produtos avaliados apresentaram atividade antibacteriana,representando possíveis substâncias com aplicabilidade na prevenção da cárie dentária.

Objective: To evaluate the in vitro antibacterial activity ofcitronellol, linalool, thymol, and D-limonene againstStreptococcus mutans, S. salivarius and S. oralis. Materialand Methods: It was performed a screening by the diffusiontechnique on solid medium. Absorbent paper discs weresoaked with 30 μl of the tested substance and then placedon petri dishes containing Mueller Hinton agar previously sownwith the bacterial inoculum. After incubation for 24 h at 37 °C,it was measured the halo of growth inhibition with the aid ofa manual caliper. Chlorhexidine (2%) was used as positivecontrol. Tests were performed in triplicate. Results: Forcitronellol, the means of the diameters of the halos, in millimeters (mm), were 10.7, 10.0, and 9.8 against S. mutans,S. salivarius and S. oralis respectively. The values foundfor thymol were 7.3, 7.3 and 8.3 mm, respectively. Thephytochemical D-limonene exhibited means of 8.0, 6.7 and6.0 mm, respectively. For linalool, the means of the haloswere 8.0 mm, 9.0 mm and 8.2 mm. Chlorhexidine was foundto show means of 17, 16.8 and 19.7 mm on S. mutans, S.oralis and S. salivarius respectively. Conclusion: The products under test showed antibacterial activity, being therefore potential substances to be applied for dental caries prevention.