Search results for "dilution"

Biological Effects of New Hydraulic Materials on Human Periodontal Ligament Stem Cells.

2019

Background: The aim of this study was: to evaluate the biological properties of new hydraulic materials: Bio-C Repair and Bio-C Sealer. Methods: Periodontal ligament stem cells were exposed to several dilutions of Bio-C Repair and Bio-C Sealer. The ion release profile and pH were determined. Metabolic activity, cell migration and cell survival were assessed using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), wound-healing assays and Annexin assays, respectively. Cells were cultured in direct contact with the surface of each material. These were then analyzed via scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). Statistical differences were ass…

Physicochemical stability of irinotecan injection concentrate and diluted infusion solutions in PVC bags

2000

Purpose. To determine the physicochemical stability of irinotecan injection concentrate and irinotecan infusion solutions after dilution in two commonly used infusion fluids (0.9% sodium chloride, 5% dextrose) in PVC bags, stored under refrigeration (2-8°C) or at room temperature either light protected or exposed to light. Methods. Stability of irinotecan injection concentrate was determined in the original amber glass vials. Diluted irinotecan infusion solutions were aseptically prepared by further dilution of irinotecan stock solution with either 0.9% sodium chloride or 5% dextrose in PVC bags, in amounts yielding irinotecan concentrations of 0.4, 1.0, or 2.8 mg/ml. Test solutions were s…

Prediction of dilutional acidosis based on the revised classical dilution concept for bicarbonate

2004

Due to the controversy surrounding the term dilutional acidosis, the classical dilution concept for bicarbonate has been rigorously revised for the prediction of pH, actual bicarbonate concentration, and base excess. In the algorithms derived for buffer solutions, blood, and whole body (1-, 2-, and 3-fluid compartment), only bicarbonate is considered. On dilution at constant Pco2, the final concentration of bicarbonate is the sum in terms of pH, due to the following processes: dilution, formation from chemical reaction with the nonbicarbonate buffers phosphate, hemoglobin, and plasma proteins, and transfer from erythrocytes and interstitial fluid to plasma. At constant Pco2, the level of c…

Base Excess and Lactate Concentration in Infusion Solutions and Blood Products

2002

Effect of the methacrylate-based endodontic sealer Epiphany on rat peritoneal macrophages viability

2011

Objective: To evaluate the effect of the endodontic sealer Epiphany on rat peritoneal macrophages viability. Materials and methods: Peritoneal macrophages were obtained from Wistar rats and resuspended in RPMI- 1640 medium. Undiluted (crude extract) and diluted extracts to 10%, 1%, 0.1%, 0.01%, 0.001% and 0.0001% of Epiphany, AH 26 and AH Plus sealers on RPMI-1640 medium were tested for cytotoxicity to rat peritoneal macrophages using the trypan blue dye exclusion assay. Data were analyzed statistically by the Kruskal-Wallis and Mann-Whitney tests at 5% significance level. Results: Crude extract of Epiphany killed 51% of cells, but was less cytotoxic that crude extracts of AH Plus and AH 26…

Newborn rabbit responsiveness to the mammary pheromone is concentration-dependent.

2004

The effect of the intensity of odour signals has rarely been investigated in the regulation of odour-guided behaviour in young mammals. This series of experiments used the mammary pheromone (MP) of the female rabbit to assess the influence of stimulus concentration on neonatal pup responsiveness. The MP is a single compound isolated from rabbit milk that releases in pups the typical head searching and oral seizing behaviour. The pups (n = 621) were exposed to graded concentrations of the MP in bioassays varying in stimulus delivery conditions. Experiment 1 demonstrated that in aqueous dilutions the MP efficiently elicits behavioural responses only within a limited range of concentrations (f…

Cytotoxic effects of two acid solutions and 2.5% sodium hypochlorite used in endodontic therapy

2010

Aim: To evaluate the cytotoxicity of 15% citric acid, 5% phosphoric acid and 2.5% NaOCl on cultured fibroblasts using MTT colorimetric assay. Methodology: Irrigating solutions of 5% phosphoric acid, 15% citric acid, and 2.5% NaOCl, diluted at 0.1% and 0.5%, were applied to cell cultures of 3T3L1 fibroblasts. The cell viability was determined by means of MTT colorimetric assay after a period of 1, 6 and 24 hours. Percentages of cell viability were analyzed using the Kruskal-Wallis test for global comparisons and the Mann-Whitney U-test for pairwise comparisons. Results: The percentage of cell viability diminished progressively over a 24 hour period in all solutions at both dilutions. At 0.1%…

Influence of artificial blood contamination of the analysis of cerebrospinal fluid

1981

The influence of artificial blood contamination on the quantitative values obtained in the routine examination of the CSF was investigated. On the basis of dilution series from CSF and blood, the correlation between the number of added erythrocytes and the results of leukocyte counts, protein, glucose and IgG estimation was studied. In addition, the influence of the time between CSF sampling and investigation on erythrocytes and leukocytes, IgG, glucose, pH value and ammonia content in CSF contaminated with blood was investigated. The following data relevant to routine examinations resulted: there are linear correlations between the number of erythrocytes artificially added to the CSF and t…

Performance and Specificity of 6 Immunoassays for TSH Receptor Antibodies: A Multicenter Study

2017

Background: The measurement of TSH receptor (TSHR) antibodies is warranted for diagnosis of Graves’ disease (GD). Objective: The performance, detection sensitivity, and specificity of 6 TSHR immunoassays were compared. Methods: Two bioassays and 4 binding assays (Kronus, Immulite, Kryptor, Dynex) were compared in a dilution study performed in patients with autoimmune thyroid disease. Both bioassays were compared to 2 binding assays using stimulatory (M22) and blocking (K1–70) monoclonal antibody (MAb) mixtures. Results: Thirty samples from stimulatory (TSAb)-positive/blocking (TBAb)-negative patients with GD were diluted serially and measured in all assays. Samples were positive until dilut…

Productive Efficiency of Decanters with Short and Variable Dynamic Pressure Cones

2003

Abstract This paper presents the results of experimental trials carried out on third-generation, variable dynamic pressure cone decanters to assess machine performance and adjust the process parameters for optimum extraction yield. The results obtained led to the following conclusions: the regulation of the differential velocity screw/bowl allows a better performance of the decanter at low dilutions of the olive paste; it is possible to obtain high efficiency at a low dilution of the olive paste achieving a higher minor compounds content and the more advanced system of regulation leads to better results according to the variations of the ratio between liquid and solid phases, thus optimisin…