Ozone ultrafine bubble water inhibits the early formation of Candida albicans biofilms

This study aimed to investigate the effect of ozone ultrafine bubble water (OUFBW) on the formation and growth of Candida albicans (C. albicans) biofilms and surface properties of denture base resins. OUFBWs were prepared under concentrations of 6 (OUFBW6), 9 (OUFBW9), and 11 ppm (OUFBW11). Phosphate buffered saline and ozone-free electrolyte aqueous solutions (OFEAS) were used as controls. Acrylic resin discs were made according to manufacturer instructions, and C. albicans was initially cultured on the discs for 1.5 h. A colony forming unit (CFU) assay was performed by soaking the discs in OUFBW for 5 min after forming a 24-h C. albicans biofilm. The discs after initial attachment for 1.5 h were immersed in OUFBW and then cultured for 0, 3, and 5 h. CFUs were subsequently evaluated at each time point. Moreover, a viability assay, scanning electron microscopy (SEM), Alamar Blue assay, and quantitative real-time polymerase chain reaction (qRT-PCR) test were performed. To investigate the long-term effects of OUFBW on acrylic resin surface properties, Vickers hardness (VH) and surface roughness (Ra) were measured. We found that OUFBW9 and OUFBW11 significantly degraded the formed 24-h biofilm. The time point CFU assay showed that C. albicans biofilm formation was significantly inhibited due to OUFBW11 exposure. Interestingly, fluorescence microscopy revealed that almost living cells were observed in all groups. In SEM images, the OUFBW group had lesser number of fungi and the amount of non-three-dimensional biofilm than the control group. In the Alamar Blue assay, OUFBW11 was found to suppress Candida metabolic function. The qRT-PCR test showed that OUFBW down-regulated ALS1 and ALS3 expression regarding cell-cell, cell-material adhesion, and biofilm formation. Additionally, VH and Ra were not significantly different between the two groups. Overall, our data suggest that OUFBW suppressed C. albicans growth and biofilm formation on polymethyl methacrylate without impairing surface properties.

Evaluation of Accuracy of Microplate Alamar Blue Assay and Proportion Method for Prompt Detection of Mycobacterium tuberculosis and Clinical Isolates of Multidrug-resistant M. tuberculosis

Background: Tuberculosis is appraised to cause the deaths of more than a billion people in the last decades. Objectives: The current study compares the performance of microplate Alamar blue assay for clinical isolates of Mycobacterium tuberculosis and multidrug-resistant tuberculosis. Microplate Alamar blue assay was performed in a central tuberculosis laboratory at Golestan University of Medical Sciences in Gorgan, Iran. Methods: In the first step, the microplate Alamar blue assay was used for the detection of 78 clinical isolates in the Golestan Regional Tuberculosis Reference Laboratory, and the results were compared with those of the proportion assay. In the second step, the microplate Alamar blue assay and the proportion assay were used for the drug susceptibility of 35 isolates. Results: In the microplate Alamar blue assay, the sensitivity was 100 (90.97 - 100), with a specificity of 74.36 (57.87 - 86.96), positive predictive value of 79.59 (65.66 - 89.76), and negative predictive value of 100 (88.06 - 100). For the microplate Alamar blue assay with rifampin, the sensitivity was 100 (89.11 - 100), specificity was 100 (29.24 - 100), positive predictive value was 100 (89.11 - 100), and negative predictive value was 100 (29.24 - 100). For the microplate Alamar blue assay with isoniazid, the sensitivity was 84.38 (67.21 - 94.72), specificity was 66.67 (9.43 - 99.16), positive predictive value was 96.43 (81.65 - 99.91), and negative predictive value was 28.57 (3.67 - 70.96). Conclusions: We found high accuracy between the microplate Alamar blue assay with rifampin and the proportion assay. The rapid and low-cost microplate Alamar blue assay is an inexpensive and appropriate assay for the detection of rifampin-resistant tuberculosis in low-income countries.

The Influence of Astaxanthin on the Proliferation of Adipose-derived Mesenchymal Stem Cells in Gelatin-Methacryloyl (GelMA) Hydrogels

Recently, astaxanthin, a red lipophilic pigment belonging to the xanthophyllic family of carotenoids, has shown the feasibility of its uses in tissue engineering and regenerative medicine, due to its excellent antioxidant activities and its abilities to enhance the self-renewal potency of stem cells. In this study, we demonstrate the influence of astaxanthin on the proliferation of adipose-derived mesenchymal stem cells in tissue-engineered constructs. The tissue engineered scaffolds were fabricated using photopolymerizable gelatin methacryloyl (GelMA) with different concentrations of astaxanthin. The effects of astaxanthin on cellular proliferation in two-dimensional environments were assessed using alamar blue assay and reverse transcription polymerase chain reaction (RT-PCR). Then, rheological properties, chemical structures and the water absorption of the fabricated astaxanthin-incorporated GelMA hydrogels were characterized using NMR analysis, rheological analysis and a swelling ratio test. Finally, the influence in three-dimensional environments of astaxanthin-incorporated GelMA hydrogels on the proliferative potentials of adipose-derived stem cells was assessed using alamar blue assay and the confocal imaging with Live/dead staining. The experimental results of the study indicate that an addition of astaxanthin promises to induce stem cell potency via proliferation, and that it can be a useful tool for a three-dimensional culture system and various tissue engineering applications.

In Vitro Antileishmanial, Antitrypanosomal And Cytotoxic —Assessment of Extracts of Three Nigerian Medicinal Plants Using Alamar Blue Assay And Cell Counting Methods.

Infections caused by protozoan species are major worldwide health problems resulting in over three million deaths annually in developing countries. Extracts of three selected plants used as medicinal plants by indigenous local communities in Nigeria were screened against Trypanosoma brucei brucei bloodstream isolates and amastigotes forms of Leishmania major and for cytotoxic activity against normal cell lines (macrophages and L929 fibroblasts) and cancer cell lines (Jurkat and SH-SY5Y) using alamar blue assay and conventional cell counting methods. Results demonstrated that two extracts, aqueous extract of Vernonia amygdalina (VA) and methanolic extract of Annona senegalensis (AS) showed significant antileishmanial activity against macrophage infectivity (=50%) without cellular damage. The percentage suppression with VA was significantly higher (p<0.05) while that of AS was comparable to the standard drug, sodium stibogluconate (SSG) (% suppression with VA=65.1; AS=48.4; SSG=40.2). Two extracts showed strong antitrypanosomal activity with EC,, and MIC,, values of less than I10ug/ml namely hexane extract of AS (2.88 and 3.12) and methanolic extract of VA (8.04 and 6.25) which were more effective than the reference drug Cymelarsan, while other extracts showed moderate to low activity with values ranging from 10 to above 20 ug/ml. Cytotoxicity studies showed that only methanolic extracts were toxic to L929 fibroblasts and macrophages while no toxicity was observed on the Jurkat and SH-SY5Y cancer cells at this concentration. Phytochemical screening using GC-MS showed the presence of polyacetylenes, ethers, fatty acids, alkaloids, flavonoids, sulphur and alcohol compounds in the active extracts. The findings of this study has shown that extracts of AS and VA contain active compounds which could serve as alternative agents in the development of antileishmanial and antitrypanosomal drugs and warrants further investigation.

Antituberculosis Activity of Brotowali (Tinospora crispa) Extract and Fractions against Mycobacterium tuberculosis using Microplate Alamar Blue Assay Method

Tuberculosis (TB), in which caused by pathogenic bacteria, Mycobacterium tuberculosis, has become the major causes of death among all of infectious diseases. The increasing incidence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) has created a need to discover a new antituberculosis drug candidate. The aim of this study was to screen extract and fractions of Tinospora crispa for activity against Mycobacterium tuberculosis H37Rv using the Microplate Alamar Blue Assay (MABA) method. T. crispa extract was prepared by maceration in ethanol (96%) and antituberculosis activity was carried out using MABA method. The result of this study showed that ethanolic extract of T. crispa exhibit antituberculosis activity with minimum inhibition concentration of 12.5 mg/ml.

ESTUDO COMPARATIVO DA ATIVIDADE ANTIBACTERIANA DE EXTRATOS VEGETAIS DE Senna spectabilis, Rosmarinus officinalis E Eugenia uniflora FRENTE À CEPA PADRÃO DE Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 6538 E Streptococcus pyogenes ATCC 19615

O interesse em terapias alternativas e o uso terapêutico por derivados de plantas vêm crescendo nos últimos anos, obtendo um grande avanço científico no aspecto químico e farmacológico, a Organização Mundial da Saúde (OMS), considera as plantas medicinais como importantes instrumentos da assistência farmacêutica. Objetivo: Determinar atividade antibacteriana comparada entre os extratos de Senna spectabilis, Rosmarinus officinalis e Eugenia uniflora frente à cepa padrão de Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 6538 e Streptococcus pyogenes ATCC 19615. As folhas de E. uniflora, R. officinallis e S. spectabilis foram coletadas no Horto de plantas medicinais da Universidade Estadual de Maringá – UEM/PR e as cepas foram fornecidas pela Universidade Paranaense – Unipar. A atividade antibacteriana foi determinada por meio da técnica do microdiluição em placa, empregando revelador de crescimento Alamar Blue Assay (MABA). A concentração mínima inibitória (CIM) empregando R. officinalis, E. uniflora, frente a cepa de S. aureus ATCC pode revelar resultados de 125 µg/mL, para extratos de S. spectabilis o CIM foi de 250 µg/mL; para S. pyogenes o CIM de 125 µg/mL foi admitido apenas para R. officinalis e S. spectabilis, E. uniflora apresentou resultados de 500 µg/mL, para P. aeruginosa o CIM para os três extratos foi superior a 500 µg/mL. Os extratos são promissores quando empregados contra S. aureus e S. pyogenes, exceto para P. aeruginosa, no entanto cabe buscar novas alternativas para tratamento deste Gram-negativo.