scholarly journals Effect of Powder/Water Ratio Variation on Viscosity, Tear Strength and Detail Reproduction of Dental Alginate Impression Material (In Vitro and Clinical Study)

Polymers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 2923
Author(s):  
Rasha M. Abdelraouf ◽  
Rania E. Bayoumi ◽  
Tamer M. Hamdy
Keyword(s):  
Strength Test ◽  
In Vitro Tests ◽  
In Vitro Test ◽  
Tear Strength ◽  
Ratio Variation ◽  
Clinical Difference ◽  
Reproduction Test ◽  
Vitro Test ◽  
Water Ratio

Background: Alginate impression is a common dental polymeric material, presented as powder to be mixed with water. Aim: 1. To analyze the effect of alginate powder/water ratio variation on viscosity, tear strength and detail reproduction by in vitro tests, and 2. To evaluate this variation’s effect on patients’ impressions. Materials and methods: Two commercial alginate products were mixed in different viscosities. Viscosity was measured by a viscometer. For the tear strength test, V-shaped specimens were used. For detail reproduction, a die with three scribed lines was used. Clinical dental impressions were examined by stereomicroscope. Results: The alginate specimens mixed with a higher powder/water ratio showed a higher viscosity and tear strength compared to those with a lower powder/water ratio. Both alginate mixtures reproduced two scribed lines in a detail reproduction test. On the other hand, no clear clinical difference was detected when examining dental impressions mixed with a different powder/water ratio. Conclusion: Although increasing the powder/water ratio of mixed alginate raised the resultant viscosity and tear strength by an in vitro test, clinically, no clear difference in tearing was detected. Detail reproduction was minimally affected by the variation in powder/water ratio.

scholarly journals Recombinant in vitro test T-SPOT.TB as a screening method for early diagnosis of tuberculosis infection

2020 ◽  
Vol 98 (4) ◽  
pp. 48-52
Author(s):  
E. P. Eremenko ◽  
E. A. Borodulina ◽  
I. A. Sergeeva ◽  
D. A. Kudlay ◽  
B. E. Borodulin
Keyword(s):  
Screening Method ◽  
Latent Tuberculosis ◽  
Tuberculosis Infection ◽  
Mantoux Test ◽  
Skin Tests ◽  
In Vitro Tests ◽  
In Vitro Test ◽  
Healthy Children ◽  
Vitro Test

In addition to standard skin tests (Mantoux test with 2 TU PPD-L and diaskintest) for the diagnosis of tuberculosis infection, in vitro tests are used. One of these tests is T-SPOT.TB being more widely used in recent years.The objective: to evaluate the effectiveness of T-SPOT.TB test for early detection of tuberculosis infection in children and adolescents in Samara Region.Subjects and methods. From 2016 to 2019, results of T-SPOT.TB tests performed in 596 children aged 2 to 17 years inclusive were analyzed; those children had no immunodiagnosis of tuberculosis infection using skin tests since their parents refused to have it.Results. It was found out that the major reason for refusing skin tests was the “fear” of visiting a TB dispensary if the result had been positive — 38.43% (n = 229). The latent tuberculosis infection according to the results of T-SPOT.TB among children with concomitant pathology made 2.6%, among healthy children – 0.7%.Conclusion. T-SPOT.TB test may be used as an alternative method for diagnosis of tuberculosis infection, should the parent refuse to have skin tests. In children with concomitant pathology, T-SPOT.TB test can serve as a leading method for immunodiagnosis of tuberculosis.The authors state that they have no conflict of interests.

scholarly journals UJI DAYAHAMBAT EUGENOL DARI DAUN CENGKEH HASIL FRAKSINASI TERHADAP PERTUMBUHAN JAMUR PATOGEN Fusarium oxysporum f.sp. Cubense Eugenol Inhibitory Test From Clove Leaf Fractionation Of Fungal Patogen Growth Fusarium oxysporum f.sp. cubense

AgriPeat ◽  
2019 ◽  
Vol 20 (02) ◽  
pp. 107-113
Author(s):  
Admin Journal
Keyword(s):  
Fusarium Oxysporum ◽  
Vacuum Distillation ◽  
Pathogenic Fungus ◽  
Lethal Concentration ◽  
In Vitro Tests ◽  
In Vitro Test ◽  
Microsoft Excel ◽  
Vitro Test

ABSTRACTThis study aims to determine the inhibition of eugenol derived from fractionation clove leaf essentialoils (CLEO) on the growth of pathogenic fungus Fusarium oxysporum f. sp. cubense (Foc) and LC50(Lethal Concentration 50). This research was in vitro, started with purification of clove leaf essentialoil, fractionation by vacuum distillation and bioassay. In vitro tests include exploration of minimuminhibition and preventability tests. Data were analyzed with Microsoft Excel 2010 program. Theresults of minimum inhibition showed at 218,75 ppm concentration of each level was able to inhibitthe growth of Foc fungi. The minimum inhibition exploration was carried out at 218,75 ppm, 109,38ppm, 54,69 ppm and 27,34 ppm. Exploration results showed that fractionated CLEO has been able toinhibit the growth of Foc fungi at 27,34 ppm in the amount of 15,60%. This concentration is used asthe lowest concentration in the inhibitory test. Furthermore, the inhibitory test was carried out startingat the highest concentration of 218,75 ppm, 109,38 ppm, 54,69 ppm and 27,34 ppm. Observationswere made for 7 days after inoculation (DAI). The results showed the best inhibition was at aconcentration of 218,75 ppm at 90,70% and LC50 at 11.17 µL.Keywords: CLEO, fractionation, Foc, in vitro test and LC50

Comparison of methods for measurement of the pressure exerted by knitted fabrics

2016 ◽  
Vol 87 (17) ◽  
pp. 2117-2126 ◽  
Author(s):  
Małgorzata Cieślak ◽  
Agnieszka Karaszewska ◽  
Ewa Gromadzińska ◽  
Izabela Jasińska ◽  
Irena Kamińska
Keyword(s):  
In Vitro Tests ◽  
Knitted Fabric ◽  
In Vitro Test ◽  
Knitted Fabrics ◽  
Weft Knitted Fabric ◽  
In Vivo Tests ◽  
Vitro Test ◽  
Warp Knitted Fabric

The article presents the results of measurements of pressure exerted by two model knitted products – bands with different structure (WI jersey weft-knitted fabric and WII openwork warp-knitted fabric). The tests were carried out with using the I-Scan system (in vivo and in vitro tests) and the STM 579 device (in vitro test). A comparative analysis of the in vivo and in vitro results for the I-Scan method and in vitro results for the I-Scan and STM 579 method was performed. It was found that the pressure values are lower for openwork warp-knitted fabric than for jersey weft-knitted fabric both in the case of the in vitro and in vivo tests, and the values of pressure for the same band are higher in the case of the in vitro tests.

In Vitro Toxicology and the Test Guidelines

1996 ◽  
Vol 24 (3) ◽  
pp. 435-438
Author(s):  
Kimmo Louekari
Keyword(s):  
Cost Effective ◽  
Test Methods ◽  
In Vitro Tests ◽  
In Vitro Test ◽  
In Vitro Methods ◽  
Effective Manner ◽  
Genotoxic Carcinogens ◽  
Vitro Test

Ethical, economical and scientific considerations should encourage the development of alternative and in vitro test methods. Before their adoption, in vitro methods need to be validated and scientifically justified. Demand for rigorous validation schemes for in vitro tests must be emphasised, even more than in the case of in vivo tests. The OECD has adopted in vitro guidelines for testing genotoxicity; several endpoints and mechanisms can be studied in a cost-effective manner in vitro. Similar advantages could be afforded if acute irritation and corrosion, as well as the non-genotoxic carcinogenic effects of chemicals, could be studied in vitro. Evaluation of the validation status of various methods used to study non-genotoxic carcinogens was begun by the Nordic Working Group on In Vitro Methods for Non-genotoxic Mechanisms in 1996. In some established OECD test guidelines (for example, the dermal irritation/corrosion test), there is already room for the application of in vitro methods which have not been formally validated. In January 1996, the OECD Workshop on Harmonisation of Validation and Acceptance Criteria for Alternative Toxicological Test Methods set the basis for internationally acceptable principles to be followed in the validation of in vitro test methods.

In Vitro Toxicity Testing: Purpose, Validation and Strategy

1990 ◽  
Vol 18 (1_part_1) ◽  
pp. 11-18 ◽  
Author(s):  
Oliver P. Flint
Keyword(s):  
Cell Function ◽  
Toxicity Testing ◽  
In Vitro Toxicity ◽  
In Vitro Tests ◽  
In Vitro Test ◽  
Vitro Test ◽  
Basal Cytotoxicity ◽  
Biological Endpoint

The fullest potential for in vitro evaluation of toxicity will be realised in the context of the process of assessing the risk of human toxicity. This article is an attempt to clarify what contributions can be made by in vitro tests and what types of in vitro test can best be used. In vitro tests are clarified according to the type of biological endpoint evaluated, first into tests for general (‘basal’) cytotoxicity and, secondly, into tests for differentiated cell function. The role of each type of test is analysed and it is suggested that tests for general cytotoxicity, as opposed to differentiated function, are difficult to interpret in terms of in vivo toxicity. A general approach to evaluating in vitro tests is described, and a strategy for using these tests is proposed.

Development of in vitro tests to predict fertility of bulls

2005 ◽  
Vol 85 (1) ◽  
pp. 47-52 ◽  
Author(s):  
G. Giritharan ◽  
N. Ramakrishnappa ◽  
A. Balendran ◽  
K. M. Cheng ◽  
R. Rajamahendran
Keyword(s):  
Acrosome Reaction ◽  
Return Rate ◽  
In Vitro Tests ◽  
In Vitro Test ◽  
Motile Sperm ◽  
Cleavage Rate ◽  
Vitro Fertilization ◽  
Frozen Semen ◽  
Vitro Test

The overall objective was to develop an in vitro test to predict fertility of bulls in the field. We investigated the bull effect on in vitro embryo production, zona binding and acrosome reaction, and the correlation of this effect to field fertility meas ured by 60–90 d non-return rate. Frozen semen from three separate ejaculates of eight unrelated young bulls, obtained from an artificial insemination (AI) center, was used. On thawing, ejaculates from each bull were pooled, motile sperm were selected and (a) subjected to immunofluorescent assay at 0 and 4 h of incubation in capacitation medium to assess acrosome status, (b) used in an in vitro fertilization assay system to assess cleavage and blastocyst production rates, and (c) sperm-zona binding assay was carried out to determine the number of sperm bound to the zona pellucida of mature oocytes. Percentage of pre-freeze motile sperm (PrFM) and non-return rate data were obtained from the AI center. PrFM, percentage of acrosome reacted sperm at 0 h (AR1), increase in percentage of acrosome reacted sperm after 4 h (InAR) and sperm-zona binding rates (ZB) differed (P < 0.05) among sperm samples obtained from different young bulls. Significant correlations (P < 0.05) were observed between PrFM and AR1 (r = -0.31), InAR (r = 0.36), and ZB (r = 0.32). AR1 was negatively correlated to ZB (r = -0.27) and cleavage rate (r = -0.20), InAR was positively correlated with ZB (r = 0.31) and cleavage rate (r = 0.26). None of the in vitro tests was correlated with non-return rate. These findings indicate that along with pre-freeze motility, a combination of in vitro tests including the percentage of spontaneously acrosome reacted sperm at thawing, might be useful in predicting bull field fertility. Such a combination of assays, however, has yet to be determined. Key words: Field fertility, acrosome reaction, zona binding, IVF, fertility assay

scholarly journals Rumen Inoculum Collected from Cows at Slaughter or from a Continuous Fermenter and Preserved in Warm, Refrigerated, Chilled or Freeze-Dried Environments for In Vitro Tests

Animals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 815 ◽  
Author(s):  
Mauro Spanghero ◽  
Maria Chiaravalli ◽  
Stefania Colombini ◽  
Carla Fabro ◽  
Federico Froldi ◽  
...  
Keyword(s):  
Rumen Fluid ◽  
Gas Production ◽  
Neutral Detergent Fiber ◽  
In Vitro Tests ◽  
In Vitro Test ◽  
Fermentative Capacity ◽  
Freeze Dried ◽  
Vitro Test ◽  
Highly Correlated

The utilization of animal donors of rumen fluid for laboratory experiments can raise ethical concerns, and alternatives to the collection of rumen fluids from live animals are urgently requested. The aim of this study was to compare the fresh rumen fluid (collected at slaughter, W) with that obtained from a continuous fermenter (RCF) and three methods of rumen fluid preservation (refrigeration, R, chilling, C, and freeze-drying, FD). The fermentability of different inoculum was evaluated by three in vitro tests (neutral detergent fiber (NDF) and crude protein (CP) degradability and gas production, NDFd, RDP and GP, respectively) using six feeds as substrates. Despite the two types of inoculum differed in terms of metabolites and microbiota concentration, the differences in vitro fermentability between the two liquids were less pronounced than expected (−15 and 20% for NDFd and GP when the liquid of fermenter was used and no differences for RDP). Within each in vitro test, the data obtained from rumen and from fermenter liquids were highly correlated for the six feeds, as well as between W and R (r: 0.837–0.985; p < 0.01). The low fermentative capacity was found for C and, particularly, FD for liquids. RCF could be used to generate inoculum for in vitro purposes and short-term refrigeration is a valuable practice to manage inoculum.

Development of an In Vitro Test Battery for the Estimation of Acute Human Systemic Toxicity: An Outline of the EDIT Project

2002 ◽  
Vol 30 (3) ◽  
pp. 313-321 ◽  
Author(s):  
Cecilia Clemedson ◽  
Marika Nordin-Andersson ◽  
Henning F. Bjerregaard ◽  
Jørgen Clausen ◽  
Anna Forsby ◽  
...  
Keyword(s):  
Systemic Toxicity ◽  
Target Organ ◽  
Test Battery ◽  
In Vitro Tests ◽  
Good Prediction ◽  
In Vitro Test ◽  
Optimal Test ◽  
Organ Specific ◽  
Vitro Test

The aim of the Evaluation-guided Development of New In Vitro Test Batteries (EDIT) multicentre programme is to establish and validate in vitro tests relevant to toxicokinetics and for organ-specific toxicity, to be incorporated into optimal test batteries for the estimation of human acute systemic toxicity. The scientific basis of EDIT is the good prediction of human acute toxicity obtained with three human cell line tests (R2 = 0.77), in the Multicentre Evaluation of In Vitro Cytotoxicity (MEIC) programme. However, the results from the MEIC study indicated that at least two other types of in vitro test ought to be added to the existing test battery to improve the prediction of human acute systemic toxicity — to determine key kinetic events (such as biotransformation and passage through biological barriers), and to predict crucial organ-specific mechanisms not covered by the tests in the MEIC battery. The EDIT programme will be a case-by-case project, but the establishment and validation of new tests will be carried through by a common, step-wise procedure. The Scientific Committee of the EDIT programme defines the need for a specific set of toxicity or toxicokinetic data. Laboratories are then invited to perform the defined tests in order to provide the “missing” data for the EDIT reference chemicals. The results obtained will be evaluated against the MEMO (the MEIC Monograph programme) database, i.e. against human acute systemic lethal and toxicity data. The aim of the round-table discussions at the 19th Scandinavian Society for Cell Toxicology (SSCT) workshop, held in Ringsted, Denmark on 6–9 September 2001, was to identify which tests are the most important for inclusion in the MEIC battery, i.e. which types of tests the EDIT programme should focus on. It was proposed that it is important to include in vitro methods for various kinetic events, such as biotransformation, absorption in the gut, passage across the blood–brain barrier, distribution volumes, protein binding, and renal clearance/accumulation. Models for target organ toxicity were also discussed. Because several of the outlier chemicals (paracetamol, digoxin, malathion, nicotine, paraquat, atropine and potassium cyanide) in the MEIC in vivo–in vitro evaluation have a neurotoxic potential, it was proposed that the development within the EDIT target organ programme should initially be focused on the nervous system.

Review of in vitro Test Systems Using DNA Damage and Repair for Screening of Chemical Carcinogens

1979 ◽  
Vol 62 (4) ◽  
pp. 857-863
Author(s):  
Gary M Williams
Keyword(s):  
Dna Damage ◽  
Tissue Injury ◽  
In Vitro Tests ◽  
In Vitro Test ◽  
Chemical Carcinogens ◽  
Dna Damage And Repair ◽  
Damage Repair ◽  
Hormonal Imbalance ◽  
Vitro Test

Abstract Chemical carcinogens are mechanistically classified as genotoxic which interact directly with DNA, and epigenetic which cause chronic tissue injury, hormonal imbalance, and promotional effects. This review evaluates in vitro tests for their contribution to a battery for identifying genotoxic chemical carcinogens. In addition to bacterial mutagenic assays, nonspecific DNA damage/repair tests are recommended for screening chemicals, in particular the hepatocyte primary culture/DNA repair test.

scholarly journals Transactivation via the human glucocorticoid and mineralocorticoid receptor by therapeutically used steroids in CV-1 cells: a comparison of their glucocorticoid and mineralocorticoid properties

2004 ◽  
Vol 151 (3) ◽  
pp. 397-406 ◽  
Author(s):  
C Grossmann ◽  
T Scholz ◽  
M Rochel ◽  
C Bumke-Vogt ◽  
W Oelkers ◽  
...  
Keyword(s):  
Test System ◽  
Expression Vectors ◽  
In Vitro Tests ◽  
In Vitro Test ◽  
Binding Affinities ◽  
Vitro Assay ◽  
Clinical Observations ◽  
Reticulocyte Lysate ◽  
Vitro Test

BACKGROUND: Glucocorticoids (GCs) are commonly used for long-term medication in immunosuppressive and anti-inflammatory therapy. However, the data describing gluco- and mineralo-corticoid (MC) properties of widely applied synthetic GCs are often based on diverse clinical observations and on a variety of in vitro tests under various conditions, which makes a quantitative comparison questionable. METHOD: We compared MC and GC properties of different steroids, often used in clinical practice, in the same in vitro test system (luciferase transactivation assay in CV-1 cells transfected with either hMR or hGRalpha expression vectors) complemented by a system to test the steroid binding affinities at the hMR (protein expression in T7-coupled rabbit reticulocyte lysate). RESULTS AND CONCLUSIONS: While the potency of a GC is increased by an 11-hydroxy group, both its potency and its selectivity are increased by the Delta1-dehydro-configuration and a hydrophobic residue in position 16 (16-methylene, 16alpha-methyl or 16beta-methyl group). Almost ideal GCs in terms of missing MC effects, as defined by our in vitro assay, are therefore prednylidene, budesonide, beclomethasone and betamethasone.The MC potency of a steroid is increased by a 9alpha- or a 6alpha-fluoro substituent. A hydrophilic substituent in position 16 (like 16-hydroxylation in triamcinolone) decreases both MC and GC properties. As no substituent that leads to an isolated reduction of GC activity could be characterized in our experiments, 9alpha-fluorocortisol, the most frequently used steroid for MC substitution, seems to be the best choice of available steroids for this purpose.

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