In vitro and ex vitro germination of Jatropha gossypiifolia and initiation of in vitro cultivation

The effect of exposure to sub-inhibitory concentrations of hypochlorite and quaternary ammonium compounds on antimicrobial susceptibility of Pseudomonas aeruginosa

Introduction: Primary teeth are equally important as permanent teeth. Endodontic therapy aids in the preservation and maintenance of extremely carious primary teeth. For root canal therapy to be successful, root canals must be properly prepared and effectively irrigated. Sodium Hypochlorite (NaOCl) has been the gold standard for root canal treatment of primary teeth. However, there are a few drawbacks to using higher concentrations of sodium hypochlorite, such as toxic reactions from its apical penetration. In addition, an excess of irrigation fluid via the apical region could harm the permanent tooth underneath. Therefore, it is crucial to select the proper concentration to preserve the delicate balance between effectiveness and safety. Aim: The present in-vitro study was conducted in the city of Chennai, Tamil Nadu, between March and June 2022. The study aimed to evaluate the effectiveness of lower concentrations of sodium hypochlorite, such as 1%, 0.5%, and 0.25%, against Enterococcus faecalis. Materials and Methods: The antibacterial activity of different concentrations of sodium hypochlorite (1%, 0.5%, and 0.25%) against Enterococcus faecalis was performed using Muller Hinton agar. Three Mueller Hinton agar plates were prepared and sterilised for 15 minutes for each concentration. The volumes used were 25 μL, 50 μL, and 100 μL, respectively. E. faecalis was swabbed and poured into the sterilised plates. The plates were incubated for 24 hours at 37°C. After incubation, the plates were examined, and their zone of Inhibition was determined. ANOVA test was applied with Post-hoc Tukey’s analysis. Results: One-way ANOVA test showed that there was a significant difference with a p-value <0.001 in all three groups. Post-hoc Tukey’s analysis was done, and the test showed that the highest zone of inhibition was seen with 1% sodium hypochlorite at 100 μL, with zone diameter of 39 mm, and the least zone of inhibition was seen with 0.25% sodium hypochlorite solution at 25 μL, with zone diamter of 22 mm. Conclusion: The results of the present study show that a 1% sodium hypochlorite solution can be used to successfully disinfect root canals, indicating its potential as an effective antimicrobial agent in endodontic procedures.

To evaluate and compare the cytotoxicity of various concentrations of sodium hypochlorite on immortalized human bone marrow mesenchymal stem cells (MSCs). The 5.25 percent sodium hypochlo-rite (NaOCl) at concentrations of 0.5, 0.1, 0.025, 0.0125, and 0.005 mg/ml were used to assess the cytotoxic effect on MSCs. Immortalized human bone marrow mesenchymal stem cells (hTERT-MSCs) were exposed to NaOCl at 5 different concentrations. Cell viability was assessed by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and alamarBlue assays. The cell morphology changes were assessed with scanning electron microscopy (SEM) after exposure to 2, 4, and 24 hour incubation. The ethidium bromide/acridine orange (EB/ AO) fuorescent stain was applied to the cells in the 8-chamber slides after they were incubated with the testing agents for 2 and 4 hours to detect live and dead cells. The observations were quantitatively and qualitatively analyzed. The cell viability study using MTT assay and AB assay showed significant reduction with varying concentration at 2 and 4 hours incubation period. The cell viability decreased with the higher percentage of NaOCl. The exposure time also revealed an inverse relation to the cell viability. The SEM analysis showed reduction in the number of cells and morphological alterations with 0.5 mg/ml at 2 and 4 hours compared to 0.025 mg/ml NaOCl. Destruction of the cells with structural alterations and lysis was evident under fuorescence microscope when the cells were exposed to 0.5 mg/ml NaOCl. Within the limitations of this in vitro study it can be concluded that NaOCl is toxic to the human bone marrow MSCs. The cell lysis was evident with higher concentration of sodium hypochlorite. From the observations, it can be concluded that a lower concentration of NaOCl may be used as endodontic irrigant due to its cytotoxic properties. Further studies are mandatory to evolve a consensus on the optimal concentration of sodium hypochlorite to be used as endodontic irrigant.

O presente trabalho teve por objetivo estabelecer in vitro a espécie Lippia alba (Mill.) N. E. Brown e promover a aclimatização de mudas dessa espécie. Para isso, foi testada a influência de diferentes concentrações e tempos de imersão em hipoclorito de sódio na assepsia dos explantes. Segmentos nodais foram imersos em hipoclorito de sódio nas concentrações 0,4; 0,6; 0,8 e 1,0 % e nos tempos 8, 12 e 16 minutos. Após 30 dias avaliou-se a contaminação bacteriana (%), número de brotos, número de folhas, e a taxa de sobrevivência (%). A concentração de 1% de hipoclorito de sódio foi a mais eficiente no controle da contaminação. Ápices caulinares de L. alba foram estabelecidos in vitro em meio MS suplementado com diferentes doses de BAP (0; 0,5; 1,0; 1,5 mg L-1). Após 140 dias avaliou-se a contaminação (%), a taxa de sobrevivência (%), a oxidação (%) e o número de brotos. Os melhores resultados foram obtidos para a dose 1,5 mg L-1 deste regulador. Para a aclimatização foram testados quatro tipos de substratos: pó de coco + calcário (1 g L-1), Plantmax® + calcário (1 g L-1), vermiculita + calcário (1 g L-1) e pó de coco + Plantmax® + vermiculita (1:1:1) + calcário (1 g L-1). Avaliou-se a taxa de sobrevivência (%), comprimento da parte aérea (cm), comprimento da raiz (cm), massa fresca da parte aérea e da raiz (g), e a massa seca da parte aérea e da raiz (g). Os melhores resultados foram obtidos quando com o substrato comercial Plantmax®.

Molybdenum removal from copper ore concentrate by sodium hypochlorite leaching

To assess the influence of concentration, temperature and surfactant addition to a sodium hypochlorite solution on its dynamic viscosity and to calculate the corresponding Reynolds number to determine the corresponding flow regimen. The dynamic viscosity of the irrigant was assessed using a rotational viscometer. Sodium hypochlorite with concentrations ranging from 0.6% to 9.6% was tested at 37 and 22 °C. A wide range of concentrations of three different surfactants was mixed in 2.4% sodium hypochlorite for viscosity measurements. The Reynolds number was calculated under each condition. Data were analysed using two-way anova. There was a significant influence of sodium hypochlorite concentration (P < 0.001) and temperature (P < 0.001) on dynamic viscosity: the latter significantly increased with sodium hypochlorite concentration and decreased with temperature. A significant influence of surfactant concentration on dynamic viscosity (P < 0.001) occurred, especially for high surfactant concentrations: 6.25% for benzalkonium chloride, 15% for Tween 80 and 6.25% for Triton X-100. Reynolds number values calculated for a given flow rate (0.14 mL s(-1)), and root canal diameter (sizes 45 and 70) clearly qualified the irrigant flow regimen as laminar. Dynamic viscosity increased with sodium hypochlorite and surfactant concentration but decreased with temperature. Under clinical conditions, all viscosities measured led to laminar flow. The transition between laminar and turbulent flow may be reached by modifying different parameters at the same time: increasing flow rate and temperature whilst decreasing irrigant viscosity by adding surfactants with a high value of critical micellar concentration.

Efficacy of Photon-induced Photoacoustic Streaming in the Reduction of Enterococcus faecalis within the Root Canal: Different Settings and Different Sodium Hypochlorite Concentrations

Devido a relevante importância econômica, tanto para o setor alimentício quanto farmacêutico, a oliveira vem sendo cada vez mais cultivada em todo o mundo. Para isso, a obtenção de mudas de qualidade com uniformidade e idoneidade varietal surge como fator altamente relevante na implantação dos pomares de oliveiras. Dessa forma, o objetivo deste trabalho foi desenvolver protocolo de estabelecimento in vitro a partir de segmentos nodais de duas cultivares de oliveira sob diferentes concentrações de hipoclorito de sódio e concentrações de BAP. O experimento foi conduzido no delineamento inteiramente casualisado, em esquema fatorial triplo (2x3x3), sendo duas cultivares de oliveira (Arbequina e Koroneiki), três concentrações de BAP (0,00; 2,22 e 4,44 µM) e três concentrações de hipoclorito de sódio (0,6; 0,8 e 1,0% de cloro ativo) para a descontaminação dos explantes. Cada tratamento contou com três repetições e a unidade experimental constituída por cinco tubos de ensaio com um explante cada. Após 28 dias, foi possível observar que os tratamentos testados não foram eficientes no estabelecimento in vitro de Olea europaea cv. Arbequina. A concentração de 2,22 µM de BAP adicionada ao meio WPM e a concentração de 1,0% de hipoclorito de sódio, utilizada na desinfestação dos explantes, são ideais para o estabelecimento in vitro de Olea europaea cv. Koroneiki.

Dental impressions are potential sources of bacterial contamination which could eventually lead to transmissible infectious diseases through the blood or saliva. Sodium hypochlorite is an effective disinfectant recommended by the American Dental Association (ADA) in a 1:10 dilution for a ten minute immersion to disinfect irreversible hydrocolloid impressions. As the ADA protocol is sometimes neglected in busy practice settings, this pilot study was designed to determine an efficient and effective protocol for disinfection of irreversible hydrocolloid impressions. Various concentrations of sodium hypochlorite and disinfection times were challenged against irreversible hydrocolloid impressions contaminated with six Gram-positive and Gram-negative bacteria. A two minute immersion time in a 0.6% solution of sodium hypochlorite protocol was found to prevent bacterial growth on the impressions. Disinfection of irreversible hydrocolloid impressions in a 0.6% solution of sodium hypochlorite for two minutes was as effective as the ADA's protocol of using a 0.5% sodium hypochlorite solution for ten minutes to destroy the test bacteria.

Characterization of chemiluminescence from singlet oxygen under laminar flow conditions in a micro-channel and its quenching with beverages

Smear Layer Removal Using Passive Ultrasonic Irrigation and Different Concentrations of Sodium Hypochlorite

Analysis of the effect of dilution on the necrotic tissue dissolution property of sodium hypochlorite

Effect of Different Concentrations of Sodium Hypochlorite on the Compressive Strength of Endodontically Treated Roots

The synergistic relationship between ultrasound and sodium hypochlorite: A scanning electron microscope evaluation

The Effect of Various Concentrations of Sodium Hypochlorite on the Ability of MTAD to Remove the Smear Layer