The optimized conditions for the in vitro micronucleus (MN) test procedures using chamber slides

2005 ◽  
Vol 27 (3) ◽  
pp. 145-151 ◽  
Author(s):  
Mika Yamamoto ◽  
Akira Motegi ◽  
Jiro Seki ◽  
Youichi Miyamae
Keyword(s):  
Test Procedures ◽  
Optimized Conditions

scholarly journals Spectrum and theIn VitroAntifungal Susceptibility Pattern of Yeast Isolates in Ethiopian HIV Patients with Oropharyngeal Candidiasis

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Birhan Moges ◽  
Adane Bitew ◽  
Aster Shewaamare
Keyword(s):  
Antifungal Agents ◽  
Antifungal Susceptibility ◽  
Antifungal Drugs ◽  
Assay Method ◽  
Cryptococcus Laurentii ◽  
Susceptibility Pattern ◽  
Test Procedures ◽  
Disk Diffusion Assay ◽  
Diffusion Assay

Background.In Ethiopia, little is known regarding the distribution and thein vitroantifungal susceptibility profile of yeasts.Objective.This study was undertaken to determine the spectrum and thein vitroantifungal susceptibility pattern of yeasts isolated from HIV infected patients with OPC.Method.Oral pharyngeal swabs taken from oral lesions of study subjects were inoculated onto Sabouraud Dextrose Agar. Yeasts were identified by employing conventional test procedures and the susceptibility of yeasts to antifungal agents was evaluated by disk diffusion assay method.Result.One hundred and fifty-five yeast isolates were recovered of which 91 isolates were from patients that were not under HAART and 64 were from patients that were under HAART.C. albicanswas the most frequently isolated species followed byC. glabrata, C. tropicalis, C. krusei, C. kefyr, Cryptococcus laurentii, and Rhodotorulaspecies. Irrespective of yeasts isolated and identified, 5.8%, 5.8%, 12.3%, 8.4%, 0.6%, and 1.3% of the isolates were resistant to amphotericin B, clotrimazole, fluconazole, ketoconazole, miconazole, and nystatin, respectively.Conclusion.Yeast colonization rate of 69.2% and 31% resistance to six antifungal agents was documented. These highlight the need for nationwide study on the epidemiology of OPC and resistance to antifungal drugs.

scholarly journals In Vitro Azole and Amphotericin B Susceptibilities of Malassezia furfur from Bloodstream Infections Using E-Test and CLSI Broth Microdilution Methods

Antibiotics ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 361 ◽  
Author(s):  
Wafa Rhimi ◽  
Chioma Inyang Aneke ◽  
Adriana Mosca ◽  
Domenico Otranto ◽  
Claudia Cafarchia
Keyword(s):  
Amphotericin B ◽  
Reading Time ◽  
Antifungal Susceptibility ◽  
Bloodstream Infections ◽  
Hospitalized Patients ◽  
Malassezia Furfur ◽  
Broth Microdilution ◽  
Test Procedures ◽  
The Media

The number of reports of Malassezia furfur bloodstream infections is constantly increasing and there is a need for more simple antifungal susceptibility methods for their management. In this study, a total of 39 M. furfur isolates collected from hospitalized patients with fungemia were screened for antifungal susceptibility to azole and amphotericin B (AmB) using Clinical and Laboratory Standards Institute broth microdilution (CLSI BMD) and E-test in Sabouraud dextrose agar + 1% Tween80 (SDAt) and mDixon agar (DIX). Essential agreement (EA) and discrepancies between the two methods were evaluated after 48 h and 72 h reading times. Itraconazole (ITZ) and posaconazole (POS) displayed the lowest MIC values whereas fluconazole (FLZ) and AmB the highest, regardless of the methods and the reading time. The EA between BMD was >95% for FLZ and voriconazole (VOR) regardless of the media in the E-tests and reading time. The EA between BMD with E-test for AmB was >97% only when E-test in SDAt was used. The EA between BMD and E-test for ITZ and POS varied according to the media in E-test procedures and the reading time and was higher than 66.6% (POS) or 72% (ITZ) only when SABt was used. Substantial discrepancies for ITZ and POS were >5.1% regardless of the media and the reading time. This study suggests that the E-test in SABt represents an alternative method to CLSI BMD to evaluate the susceptibility of M. furfur to FLZ, VOR and AmB and not for ITZ and POS.

scholarly journals In Vitro Reconstitution of the End Replication Problem

2001 ◽  
Vol 21 (17) ◽  
pp. 5753-5766 ◽  
Author(s):  
Rieko Ohki ◽  
Toshiki Tsurimoto ◽  
Fuyuki Ishikawa
Keyword(s):  
Mammalian Cells ◽  
Simian Virus 40 ◽  
Simian Virus ◽  
Telomere Attrition ◽  
Linear Dna ◽  
In Vitro Reconstitution ◽  
Biochemical Approach ◽  
Optimized Conditions ◽  
Lagging Strand

ABSTRACT The end replication problem hypothesis proposes that the ends of linear DNA cannot be replicated completely during lagging strand DNA synthesis. Although the idea has been widely accepted for explaining telomere attrition during cell proliferation, it has never been directly demonstrated. In order to take a biochemical approach to understand how linear DNA ends are replicated, we have established a novel in vitro linear simian virus 40 DNA replication system. In this system, terminally biotin-labeled linear DNAs are conjugated to avidin-coated beads and subjected to replication reactions. Linear DNA was efficiently replicated under optimized conditions, and replication products that had replicated using the original DNA templates were specifically analyzed by purifying bead-bound replication products. By exploiting this system, we showed that while the leading strand is completely synthesized to the end, lagging strand synthesis is gradually halted in the terminal ∼500-bp region, leaving 3′ overhangs. This result is consistent with observations in telomerase-negative mammalian cells and formally demonstrates the end replication problem. This study provides a basis for studying the details of telomere replication.

scholarly journals Synthesis and Antimicrobial Activity of Burkholderia-Related 4-Hydroxy-3-Methyl-2-Alkenylquinolones (HMAQs) and Their N-Oxide Counterparts

2020 ◽  
Author(s):  
Marianne Piochon ◽  
Pauline M. L. Coulon ◽  
Armand Caulet ◽  
Marie-Christine Groleau ◽  
Eric Déziel ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Biologically Active ◽  
Specific Class ◽  
Gram Positive ◽  
Carbonate Group ◽  
Gram Positive Bacteria ◽  
Alkenyl Chain ◽  
Optimized Conditions ◽  
Burkholderia Ambifaria

ABSTRACT: The Burkholderia genus offers a promising potential in medicine because of the diversity of biologically active natural products encoded in its genome. Some pathogenic Burkholderia spp. biosynthesize a specific class of antimicrobial 2-alkyl-4(1H)-quinolones, i.e., 4-hydroxy-3-methyl-2-alkenylquinolones (HMAQs) and their N-oxide derivatives (HMAQNOs). Herein, we report the synthesis of a series of six HMAQs and HMAQNOs featuring a trans-∆<sup>2</sup> double bond at the C2-alkyl chain. The quinolone scaffold was obtained via the Conrad-Limpach approach while the (E)-2-alkenyl chain was inserted through Suzuki-Miyaura cross-coupling under microwave radiation without noticeable isomerization according to the optimized conditions. Subsequent oxidation of enolate-protected HMAQs cleanly led to the formation of HMAQNOs following cleavage of the ethyl carbonate group. Synthetic HMAQs and HMAQNOs were in vitro evaluated for their antimicrobial activity against different Gram-negative and Gram-positive bacteria as well as against fungi and yeasts. The biological results support and extend the potential of HMAQs and HMAQNOs as antimicrobials, especially against Gram-positive bacteria. We also confirm the involvement of HMAQs in the autoregulation of the Hmq system in Burkholderia ambifaria.

scholarly journals In-vitro study of quality control parameters of three different brands of azithromycin tablets

2017 ◽  
Vol 6 (7) ◽  
pp. 1572
Author(s):  
Rashmi Singh ◽  
Monika Saxena ◽  
Deeksha Sahay ◽  
Sujata Singh
Keyword(s):  
In Vitro Study ◽  
Quality Parameters ◽  
Pharmaceutical Companies ◽  
Dissolution Profile ◽  
Test Procedures ◽  
Disintegration Time ◽  
Weight Variation ◽  
Quality Control Parameters ◽  
Standard Value

Background: Azithromycin, being a very important antibiotic, is manufactured by different pharmaceutical companies and available in numerous brands. Therefore, it requires a quantitative evaluation and assessment of tablets chemical, physical and bioavailability properties.Methods: The physicochemical quality pararametrs like weight variation, size, hardness, friability, disintegration time and dissolution profile of three brands of azithromycin tablets were assessed by performing various test procedures according to established methods.Results: The different brands of tablets showed very slight variations in weight and size, not exceeding more than 5% of standard value. Similarly, hardness of all the brands was less than 5kg/f and friability ranged from 0.2 to 0.5%. All the brands tested disintegrated in <6 minutes and all the brands released >75% of the active ingredient within 45 minutes.Conclusions: All the physiochemical quality parameters of three brands of azithromycin tablets were found to be within the pharmacopeial specifications therefore all the brands were pharmaceutically and chemically equivalent and can be freely interchanged.

Optimized steps in fluorometric determination of thiobarbituric acid-reactive substances in serum: importance of extraction pH and influence of sample preservation and storage

1993 ◽  
Vol 39 (12) ◽  
pp. 2522-2526 ◽  
Author(s):  
W Wasowicz ◽  
J Nève ◽  
A Peretz
Keyword(s):  
Thiobarbituric Acid ◽  
Thiobarbituric Acid Reactive Substances ◽  
Fluorometric Method ◽  
C Storage ◽  
Insulin Dependent ◽  
The Mean ◽  
Optimized Conditions ◽  
And Storage

Abstract A simple, reliable, and reproducible fluorometric method for measuring thiobarbituric acid-reactive substances (TBARS) in serum is proposed, based on the reaction between malondialdehyde (MDA) and thiobarbituric acid. Formation of TBARS was complete at pH 2.4-2.6, but extraction with n-butanol proved complete only at lower pH, i.e., 1.6-1.7. Analytical recoveries of MDA added to serum were 94%-101%; within- and between-run CVs were 2.4-3.6% and 4.6-5.5%; and the detection limit for TBARS in serum was 0.10 mumol/L. Optimized conditions included: (a) collection of either serum or heparinized plasma, (b) preservation from in vitro autoxidation by glutathione and EDTA, and (c) storage at -20 degrees C up to 35 days. The mean (+/- SD) TBARS concentration in 47 healthy adults was 1.01 (0.21) mumol/L; no sex-related difference was observed. Higher concentrations were measured in patients with renal insufficiency undergoing hemodialysis and in patients with insulin-dependent diabetes, chronic pancreatitis, or liver cirrhosis.

STUDIES ON PLATELET AGGREGATION BY IMPEDANCE AGGREGOMETRY AND ATP SECRETION IN NON-ANTICOAGULANT BLOOD

1987 ◽  
Author(s):  
W Heptner ◽  
J R Suárez ◽  
V Lütgendorf
Keyword(s):  
Whole Blood ◽  
Ex Vivo ◽  
Great Effort ◽  
Clotting Time ◽  
Test Procedures ◽  
Present Contribution ◽  
Platelet Factor ◽  
Atp Secretion ◽  
Impedance Aggregometry

Investigations in vitro on the time-dependent increase in thrombin activityand platelet function have been used tocharacterize the kinetics of the clotting process in nonanticoagulated blood. The test procedures described involve great effort and expense and therefore are not suitable for routine tests in pharmacology and clinical pharmacology. The present contribution describes the determination of clotting times in ATP secretion in the Chrono-Log Whole Blood Aggregometer.Blood was taken from healthy donors who had not used any drug in the two weeks before the trial. 0.5 ml blood wereimmediately transfered into siliconizedglass cuvettes containing 0.4 ml salineand 0.1 ml luciferin-luciferase cocktail prewarmed to 37°C. Impedance and luminescence were recorded continuously. Clotting at the electrodes is indicated by an immediate steep rise in both impedance and luminescence. Clotting time is defined as the time from diluting the blood in the cuvettes until the point at which marked elevation of these variables begins.In the blood of twelve subjects the mean clotting time was 3.8 min and intersubject variation (SD) was 0.45 min. Drastic interindividual differences in response to collagen and ADP in citratedwhole blood were observed in the study group.In vitro addition of 20 μl Fibraccel(Behringwerke AG, Marburg, FRG),a platelet factor 3 containing plateletextract decreased clotting time by 35 %(n=10). In the presence of 0.2 U heparin a slow and lona-lasting increase in impedance was seen. 1 g oral AspirinR didnot influence clotting time measured ex vivo.The results indicate that whole blood aggregometry is a simple, fast, and precise method of determining blood clotting and the effects of drugs in a medium reflecting almost physiological conditions.

A Rapid Method for the Estimation of Fibrinolytic Changes in the Dog

1958 ◽  
Vol 193 (2) ◽  
pp. 283-288 ◽  
Author(s):  
R. A. Heinrich ◽  
F. E. Noe ◽  
E. C. Vonder Heide
Keyword(s):  
Rapid Method ◽  
Test Procedure ◽  
Protamine Sulfate ◽  
Fibrinolytic System ◽  
In Vitro Test ◽  
Bleeding Diathesis ◽  
Test Procedures ◽  
Vitro Test

The fibrinolytic system in the dog was studied for investigating possible etiological factors concerned with the bleeding diathesis observed following surgery and shock. Canine profibrinolysin is poorly activated with streptokinase and therefore provided the basis for the test procedure for fibrinolysin. Marked fibrinolytic activation was observed in dogs as early as 5 minutes after 2.5 mg/kg of protamine sulfate was given intravenously. Heparin produced inhibition of the fibrinolytic system. This protamine activation and heparin inhibition was shown both in vivo and in vitro. Test procedures are presented for the estimation of profibrinolysin, fibrinolysin and antifibrinolysin. Activation of the fibrinolytic system through surgery, hyperventilation or protamine sulfate, was followed by an increase in antilysin but no change in total fibrinolysin concentration was noted.

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