Determination of susceptibility/resistance to antifungal drugs ofTrichophyton mentagrophytesisolates by a macrodilution method

2005 ◽  
Vol 51 (11) ◽  
pp. 983-987 ◽  
Author(s):  
Maria Elisabete da Silva Barros ◽  
Júnia Soares Hamdan
Keyword(s):  
Human Population ◽  
Culture Medium ◽  
Susceptibility Testing ◽  
Trichophyton Mentagrophytes ◽  
Antifungal Drugs ◽  
The Other ◽  
Minimal Inhibitory Concentrations ◽  
Adult Human

Onychomycosis is a common adult human mycosis, and dermatophytes of the Trichophyton genera are the most frequently isolated microorganism. Globally, from 3% to 10% of the human population is attacked by ony cho mycosis, and many cases involve toenails. The aim of this work was to determine the minimal inhibitory concentrations (MICs) of antifungal drugs (fluconazole, ketoconazole, itraconazole, terbinafine, and griseofulvin) often used for the treatment of ungueal dermatophytosis caused by Trichophyton mentagrophytes. The MICs were determined by the broth medium macrodilution method. The results showed that activities of terbinafine and itraconazole were significantly higher (MIC <0.007–0.015 µg·mL–1and MIC = 0.062–1.000 µg·mL–1, respectively). All isolates had reduced susceptibility to fluconazole (MIC = 16 to >64 µg·mL–1). The MICs of ketoconazole and griseofulvin varied among strains, ranging from 0.125 to 2.000 µg·mL–1for ketoconazole and from 0.25 to 2.00 µg·mL–1for griseofulvin. These MICs were higher than those of other studies cited, possibly because of differences in culture medium used in the other studies.Key words: dermatophytes, susceptibility testing, macrodilution, onychomycosis, antifungal drugs.

scholarly journals A Review: Antifungal Potentials of Medicinal Plants

2015 ◽  
Vol 2 (2) ◽  
Author(s):  
Ghulam Murtaza ◽  
Muhammad Mukhtar ◽  
Aysha Sarfraz
Keyword(s):  
Medicinal Plants ◽  
Infectious Diseases ◽  
Broad Spectrum ◽  
Human Population ◽  
Fungal Infections ◽  
Emerging Infectious Diseases ◽  
Antifungal Drugs ◽  
The Other ◽  
Antifungal Effects ◽  
Emerging Fungal Infections

Medicinal plants have been widely used to treat a variety of infectious and non-infectious diseases. According to an estimate, 25% of the commonly used medicines contain compounds isolated from plants. Several plants could offer a rich reserve for drug discovery of infectious diseases, particularly in an era when the latest separation techniques are available on one hand, and the human population is challenged by a number of emerging infectious diseases on the other hand. Among several other ailments, fungal infections are posing a great threat to the mankind, as a large number of people suffer from fungal infections worldwide due to emerging resistance of fungal strains. The available antifungal drugs are either too costly or are accompanied with several side effects. Of importance, a variety of medicinal plants have shown promise to treat a number of fungal infections, and some of them possess broad-spectrum antifungal activity. This article describes potential antifungal properties of medicinal plants against fungi, and suggests screening the potential of plants possessing broad-spectrum antifungal effects against emerging fungal infections.

scholarly journals Evaluation of susceptibility of Trichophyton mentagrophytes and Trichophyton rubrum clinical isolates to antifungal drugs using a modified CLSI microdilution method (M38-A)

2007 ◽  
Vol 56 (4) ◽  
pp. 514-518 ◽  
Author(s):  
Maria Elisabete da Silva Barros ◽  
Daniel de Assis Santos ◽  
Júnia Soares Hamdan
Keyword(s):  
Antifungal Agents ◽  
Susceptibility Testing ◽  
Incubation Temperature ◽  
Trichophyton Rubrum ◽  
Trichophyton Mentagrophytes ◽  
Antifungal Drugs ◽  
Standard Protocol ◽  
Broth Microdilution ◽  
Microdilution Method ◽  
Broth Microdilution Method

Onychomycosis is a common adult human mycosis, and dermatophytes of the Trichophyton genera are the most common causative agent. Many antimycotic agents are safe and highly effective for the treatment of dermatophytosis, and are available for clinical practice. Successful treatment depends on the ability of antifungal drugs to eradicate the fungal isolates. The aim of this work was to determine the MICs of four antifungal drugs (fluconazole, itraconazole, terbinafine and griseofulvin) recognized for ungual dermatophytosis treatment caused by Trichophyton species, especially Trichophyton mentagrophytes and Trichophyton rubrum. MICs were determined using a broth microdilution method in accordance with Clinical and Laboratory Standards Institute approved standard M38-A with some modifications, such as an incubation temperature of 28 °C, an incubation time of 7 days and inocula constituted of only microconidia. The results showed that the activities of terbinafine and itraconazole were significantly higher (MICs of <0.007–0.031 and 0.015–0.25 μg ml−1, respectively) than other tested agents. All isolates had reduced susceptibility to fluconazole (1–64 μg ml−1). The MIC of griseofulvin varied among strains (MICs of 0.062–1 μg ml−1). The parameters adopted to perform susceptibility testing of T. rubrum and T. mentagrophytes to antifungal agents appeared to be suitable and reliable, and could contribute to the possible development of a standard protocol.

scholarly journals Population differentiation, antifungal susceptibility, and host range of Trichophyton mentagrophytes isolates causing recalcitrant infections in humans and animals

2020 ◽  
Vol 39 (11) ◽  
pp. 2099-2113
Author(s):  
Sebastian Gnat ◽  
Dominik Łagowski ◽  
Aneta Nowakiewicz ◽  
Marcelina Osińska ◽  
Łukasz Kopiński
Keyword(s):  
Host Range ◽  
Susceptibility Testing ◽  
Antifungal Susceptibility ◽  
Trichophyton Mentagrophytes ◽  
Antifungal Susceptibility Testing ◽  
Antifungal Drugs ◽  
Genomic Diversity ◽  
Clinical Isolates ◽  
Chemical Groups

Abstract The major problems in determining the causative factors of the high prevalence of dermatophytoses include the lack of a well-standardized antifungal susceptibility testing method, the low consistency of in vitro and clinical minimal inhibitory concentration values, the high genomic diversity of the population, and the unclear mechanism of pathogenicity. These factors are of particular importance when the disease is recalcitrant and relapses. Herein, we identified and characterized Trichophyton mentagrophytes isolates obtained from therapy-resistant cases in humans and animals. We used genomic diversity analysis of 17 human and 27 animal clinical isolates with the MP-PCR technique, determined their phenotypic enzymatic activity and host range, and performed antifungal susceptibility testing to currently available antifungal drugs from various chemical groups. Genomic diversity values of 35.3% and 33.3% were obtained for clinical isolates from humans and animals, respectively, yet without any relationship to the host species or antifungal drug to which resistance in therapy was revealed. The highest activity of keratinase enzymes was recorded for fox, guinea pig, and human hairs. These hosts can be considered as the main species in the host range of these isolates. A phenyl morpholine derivative, i.e. amorolfine, exhibited superior activity against strains obtained from both humans and animals with the lowest MIC50. Interestingly, high compliance of terbinafine in vitro resistance with clinical problems in the treatment with this substance was shown as well. The high resistance of dermatophytes to drugs is the main cause of the recalcitrance of the infection, whereas the other features of the fungus are less important.

Determination of the lattice translation across {110} APBs in GaAs

1988 ◽  
Vol 46 ◽  
pp. 600-601
Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter
Keyword(s):  
Grain Boundaries ◽  
Lower Energy ◽  
Antiphase Boundary ◽  
The Other ◽  
Boundary Structure ◽  
Interface Plane ◽  
Inversion Symmetry ◽  
High Angle ◽  
Equilibrium Distance

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.

Determination of the Burgers vector of a dislocation in a Fe-Mn alloy by weak-beam image in HVEM

1978 ◽  
Vol 36 (1) ◽  
pp. 330-331
Author(s):  
Y. Ishida ◽  
H. Ishida ◽  
K. Kohra ◽  
H. Ichinose
Keyword(s):  
High Order ◽  
Simulation Technique ◽  
The Other ◽  
Image Simulation ◽  
Diffraction Vector ◽  
Burgers Vector ◽  
Weak Beam ◽  
Beam Image ◽  
Edge Component

IntroductionA simple and accurate technique to determine the Burgers vector of a dislocation has become feasible with the advent of HVEM. The conventional image vanishing technique(1) using Bragg conditions with the diffraction vector perpendicular to the Burgers vector suffers from various drawbacks; The dislocation image appears even when the g.b = 0 criterion is satisfied, if the edge component of the dislocation is large. On the other hand, the image disappears for certain high order diffractions even when g.b ≠ 0. Furthermore, the determination of the magnitude of the Burgers vector is not easy with the criterion. Recent image simulation technique is free from the ambiguities but require too many parameters for the computation. The weak-beam “fringe counting” technique investigated in the present study is immune from the problems. Even the magnitude of the Burgers vector is determined from the number of the terminating thickness fringes at the exit of the dislocation in wedge shaped foil surfaces.

Procedures for the Quantitative Determination of Autoprothrombin C

1962 ◽  
Vol 08 (03) ◽  
pp. 434-441 ◽  
Author(s):  
Edmond R Cole ◽  
Ewa Marciniak ◽  
Walter H Seegers
Keyword(s):  
Quantitative Determination ◽  
Plasma Sample ◽  
Quantitative Measure ◽  
The Other ◽  
Clotting Time ◽  
Bovine Plasma ◽  
Autoprothrombin C

SummaryTwo quantitative procedures for autoprothrombin C are described. In one of these purified prothrombin is used as a substrate, and the activity of autoprothrombin C can be measured even if thrombin is in the preparation. In this procedure a reaction mixture is used wherein the thrombin titer which develops in 20 minutes is proportional to the autoprothrombin C in the reaction mixture. A unit is defined as the amount which will generate 70 units of thrombin in the standardized reaction mixture. In the other method thrombin interferes with the result, because a standard bovine plasma sample is recalcified and the clotting time is noted. Autoprothrombin C shortens the clotting time, and the extent of this is a quantitative measure of autoprothrombin C activity.

Determination of Factor XIII Activity and of Factor XIII Inhibitors Using an Ammonium-Sensitive Electrode

1983 ◽  
Vol 50 (02) ◽  
pp. 563-566 ◽  
Author(s):  
P Hellstern ◽  
K Schilz ◽  
G von Blohn ◽  
E Wenzel
Keyword(s):  
Factor Xiii ◽  
Normal Subjects ◽  
The Other ◽  
Activity Measurement ◽  
Factor Xiii Deficiency ◽  
Assay Procedure ◽  
Stabilization Factor ◽  
Release Method ◽  
Sensitive Electrode

SummaryAn assay for rapid factor XIII activity measurement has been developed based on the determination of the ammonium released during fibrin stabilization. Factor XIII was activated by thrombin and calcium. Ammonium was measured by an ammonium-sensitive electrode. It was demonstrated that the assay procedure yields accurate and precise results and that factor XIII-catalyzed fibrin stabilization can be measured kinetically. The amount of ammonium released during the first 90 min of fibrin stabilization was found to be 7.8 ± 0.5 moles per mole fibrinogen, which is in agreement with the findings of other authors. In 15 normal subjects and in 15 patients suffering from diseases with suspected factor XIII deficiency there was a satisfactory correlation between the results obtained by the “ammonium-release-method”, Bohn’s method, and the immunological assay (r1 = 0.65; r2= 0.70; p<0.01). In 3 of 5 patients with paraproteinemias the values of factor XIII activity determined by the ammonium-release method were markedly lower than those estimated by the other methods. It could be shown that inhibitor mechanisms were responsible for these discrepancies.

scholarly journals Microscopic Analysis of Bacterial Inoculum Effect Using Micropatterned Biochip

Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 300
Author(s):  
Jung Ho Hwang ◽  
Sang Young Lee ◽  
Jungil Choi
Keyword(s):  
Susceptibility Testing ◽  
Inhibitory Concentration ◽  
Microscopic Analysis ◽  
Microfluidic System ◽  
Timely Manner ◽  
Testing Conditions ◽  
Bacterial Inoculum ◽  
Clinical Environments ◽  
Inoculum Effect

Antimicrobial resistance has become a major problem in public health and clinical environments. Against this background, antibiotic susceptibility testing (AST) has become necessary to cure diseases in an appropriate and timely manner as it indicates the necessary concentration of antibiotics. Recently, microfluidic based rapid AST methods using microscopic analysis have been shown to reduce the time needed for the determination of the proper antibiotics. However, owing to the inoculum effect, the accurate measurement of the minimal inhibitory concentration (MIC) is difficult. We tested four standard bacteria: Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Enterococcus faecalis, against five different antibiotics: piperacillin, cefotaxime, amikacin, levofloxacin, and ampicillin. The results showed that overall, the microfluidic system has a similar inoculum effect compared to the conventional AST method. However, due to the different testing conditions and determination protocols of the growth of the microfluidic based rapid AST, a few results are not identical to the conventional methods using optical density. This result suggests that microfluidic based rapid AST methods require further research on the inoculum effect for practical use in hospitals and can then be used for effective antibiotic prescriptions.

Determination of the Number of Conserved Chromosomal Segments Between Species

Genetics ◽  
2001 ◽  
Vol 157 (3) ◽  
pp. 1387-1395 ◽  
Author(s):  
Sudhir Kumar ◽  
Sudhindra R Gadagkar ◽  
Alan Filipski ◽  
Xun Gu
Keyword(s):  
Statistical Approach ◽  
Common Ancestor ◽  
Chromosomal Rearrangements ◽  
Structural Similarity ◽  
The Other ◽  
Segment Length ◽  
Human Genomes ◽  
Genomic Divergence ◽  
Human And Mouse

AbstractGenomic divergence between species can be quantified in terms of the number of chromosomal rearrangements that have occurred in the respective genomes following their divergence from a common ancestor. These rearrangements disrupt the structural similarity between genomes, with each rearrangement producing additional, albeit shorter, conserved segments. Here we propose a simple statistical approach on the basis of the distribution of the number of markers in contiguous sets of autosomal markers (CSAMs) to estimate the number of conserved segments. CSAM identification requires information on the relative locations of orthologous markers in one genome and only the chromosome number on which each marker resides in the other genome. We propose a simple mathematical model that can account for the effect of the nonuniformity of the breakpoints and markers on the observed distribution of the number of markers in different conserved segments. Computer simulations show that the number of CSAMs increases linearly with the number of chromosomal rearrangements under a variety of conditions. Using the CSAM approach, the estimate of the number of conserved segments between human and mouse genomes is 529 ± 84, with a mean conserved segment length of 2.8 cM. This length is &lt;40% of that currently accepted for human and mouse genomes. This means that the mouse and human genomes have diverged at a rate of ∼1.15 rearrangements per million years. By contrast, mouse and rat are diverging at a rate of only ∼0.74 rearrangements per million years.

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