scholarly journals Amphotericin B-Induced in vitro Postantifungal Effect onCandidaSpecies of Oral Origin

2012 ◽  
Vol 21 (5) ◽  
pp. 442-446 ◽  
Author(s):  
A.N.B. Ellepola
Keyword(s):  
Amphotericin B ◽  
Postantifungal Effect

scholarly journals Dynamic Interaction between Fluconazole and Amphotericin B against Cryptococcus gattii

2012 ◽  
Vol 56 (5) ◽  
pp. 2553-2558 ◽  
Author(s):  
Julliana Ribeiro Alves Santos ◽  
Ludmila Ferreira Gouveia ◽  
Erika Linzi Silva Taylor ◽  
Maria Aparecida Resende-Stoianoff ◽  
Gerson Antônio Pianetti ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Cryptococcus Gattii ◽  
Content Type ◽  
Antagonistic Interaction ◽  
Ergosterol Content ◽  
Kill Curve ◽  
Time Kill ◽  
Postantifungal Effect

ABSTRACTCryptococcus gattiiis the main pathogen of cryptococcosis in healthy patients and is treated mainly with fluconazole and amphotericin B. The combination of these drugs has been questioned because the mechanisms of action could lead to a theoretical antagonistic interaction. We evaluated distinct parameters involved in thein vitrocombination of fluconazole and amphotericin B againstCryptococcus gattii. Fourteen strains ofC. gattiiwere used for the determination of MIC, fractional inhibitory concentration, time-kill curve, and postantifungal effect (PAFE). Ergosterol quantification was performed to evaluate the influence of ergosterol content on the interaction between these antifungals. Interaction between the drugs varied from synergistic to antagonistic depending on the strain and concentration tested. Increasing fluconazole levels were correlated with an antagonistic interaction. A total of 48 h was necessary for reducing the fungal viability in the presence of fluconazole, while 12 h were required for amphotericin B. When these antifungals were tested in combination, fluconazole impaired the amphotericin B activity. The ergosterol content decreased with the increase of fluconazole levels and it was correlated with the lower activity of amphotericin B. The PAFE found varied from 1 to 4 h for fluconazole and from 1 to 3 h for amphotericin B. The interaction of fluconazole and amphotericin B was concentration-dependent and special attention should be directed when these drugs are used in combination againstC. gattii.

scholarly journals In Vitro Pharmacodynamic Characteristics of Amphotericin B, Caspofungin, Fluconazole, and Voriconazole against Bloodstream Isolates of Infrequent Candida Species from Patients with Hematologic Malignancies

2004 ◽  
Vol 48 (11) ◽  
pp. 4453-4456 ◽  
Author(s):  
Giovanni Di Bonaventura ◽  
Ilaria Spedicato ◽  
Carla Picciani ◽  
Domenico D'Antonio ◽  
Raffaele Piccolomini
Keyword(s):  
Amphotericin B ◽  
Hematologic Malignancies ◽  
Candida Guilliermondii ◽  
Fungistatic Activity ◽  
Candida Kefyr ◽  
Candida Lusitaniae ◽  
Time Kill ◽  
Postantifungal Effect ◽  
Dose Dependent

ABSTRACT Time-kill and postantifungal effect (PAFE) of amphotericin B, caspofungin, fluconazole, and voriconazole were determined against clinical isolates of Candida guilliermondii, Candida kefyr, and Candida lusitaniae. Azoles displayed fungistatic activity and no measurable PAFE, regardless of the concentration tested. Amphotericin B and caspofungin demonstrated concentration-dependent fungicidal activity, although amphotericin B only produced a significant dose-dependent PAFE against all isolates tested.

scholarly journals Method for Measuring Postantifungal Effect in Aspergillus Species

2002 ◽  
Vol 46 (6) ◽  
pp. 1960-1965 ◽  
Author(s):  
Roxana G. Vitale ◽  
Johan W. Mouton ◽  
Javier Afeltra ◽  
Jacques F. G. M. Meis ◽  
Paul E. Verweij
Keyword(s):  
Amphotericin B ◽  
Growth Curve ◽  
Clinical Laboratory ◽  
Growth Curves ◽  
National Committee ◽  
Control Growth ◽  
And Control ◽  
Postantifungal Effect

ABSTRACT An in vitro method for determination of postantifungal effect (PAFE) in molds was developed by using three isolates each of Aspergillus fumigatus, A. flavus, A. terreus, A. nidulans, and A. ustus. MICs of amphotericin B and itraconazole were determined by using National Committee for Clinical Laboratory Standards guidelines (M38-P). The inoculum was prepared in RPMI 1640 broth buffered with MOPS (morpholinepropanesulfonic acid) at pH 7.0, and conidia were exposed to amphotericin B and itraconazole at concentrations of 4, 1, and 0.25 times the MIC, each for 4, 2, and 1 h at 37°C. The same procedure was followed for controls with drug-free medium. Following exposure, the conidia were washed three times in saline and the numbers of CFU per milliliter were determined. Exposed and control conidia were then inoculated into microtitration plates and incubated at 37°C for 48 h in a spectrophotometer reader. The optical density (OD) was measured automatically at 10-min intervals, resulting in growth curves. PAFE was quantified by comparing three arbitrary points in the control growth curve, the first increase of OD and the points when 20 and 50% of the maximal growth were reached, with the growth curve of drug-exposed conidia. Amphotericin B induced PAFE in A. fumigatus at four times the MIC after 2 and 4 h of exposure ranging from 1.83 to 6.00 h and 9.33 to 10.80 h, respectively. Significantly shorter PAFEs or lack of PAFE was observed for A. terreus, A. ustus, and A. nidulans. Itraconazole did not induce measurable PAFE in the Aspergillus isolates at any concentration or exposure time tested. Further studies are warranted to investigate the implications of PAFE in relation to clinical efficacy and dosing frequency.

scholarly journals Invasive infections with Purpureocillium lilacinum: clinical characteristics and outcome of 101 cases from FungiScope® and the literature

2021 ◽  
Author(s):  
Rosanne Sprute ◽  
Jon Salmanton-García ◽  
Ertan Sal ◽  
Xhorxha Malaj ◽  
Zdeněk Ráčil ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Organ Transplant ◽  
Solid Organ ◽  
Intrinsic Resistance ◽  
Breakthrough Infection ◽  
Purpureocillium Lilacinum ◽  
Invasive Infections ◽  
Oncological Diseases ◽  
Overall Mortality

Abstract Objectives To provide a basis for clinical management decisions in Purpureocillium lilacinum infection. Methods Unpublished cases of invasive P. lilacinum infection from the FungiScope® registry and all cases reported in the literature were analysed. Results We identified 101 cases with invasive P. lilacinum infection. Main predisposing factors were haematological and oncological diseases in 31 cases (30.7%), steroid treatment in 27 cases (26.7%), solid organ transplant in 26 cases (25.7%), and diabetes mellitus in 19 cases (18.8%). The most prevalent infection sites were skin (n = 37/101, 36.6%) and lungs (n = 26/101, 25.7%). Dissemination occurred in 22 cases (21.8%). Pain and fever were the most frequent symptoms (n = 40/101, 39.6% and n = 34/101, 33.7%, respectively). Diagnosis was established by culture in 98 cases (97.0%). P. lilacinum caused breakthrough infection in 10 patients (9.9%). Clinical isolates were frequently resistant to amphotericin B, whereas posaconazole and voriconazole showed good in vitro activity. Susceptibility to echinocandins varied considerably. Systemic antifungal treatment was administered in 90 patients (89.1%). Frequently employed antifungals were voriconazole in 51 (56.7%) and itraconazole in 26 patients (28.9%). Amphotericin B treatment was significantly associated with high mortality rates (n = 13/33, 39.4%, P = <0.001). Overall mortality was 21.8% (n = 22/101) and death was attributed to P. lilacinum infection in 45.5% (n = 10/22). Conclusions P. lilacinum mainly presents as soft-tissue, pulmonary or disseminated infection in immunocompromised patients. Owing to intrinsic resistance, accurate species identification and susceptibility testing are vital. Outcome is better in patients treated with triazoles compared with amphotericin B formulations.

scholarly journals Polishing the Therapy of Onychomycosis Induced by Candida spp.: Amphotericin B–Loaded Nail Lacquer

Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 784
Author(s):  
Aleph M. S. Souza ◽  
Renato C. A. Ribeiro ◽  
Gleyse K. L. O. Pinheiro ◽  
Francisco I. Pinheiro ◽  
Wógenes N. Oliveira ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Ex Vivo ◽  
Drug Loading ◽  
Drug Bioavailability ◽  
Candida Spp ◽  
Drying Time ◽  
Analytical Method Validation ◽  
Nail Lacquer ◽  
In Vitro Adhesion

Onychomycosis induced by Candida spp. has several limitations regarding its treatment. Nail lacquers display the potential to overcome these drawbacks by providing therapeutic compliance and increasing local drug bioavailability. Thus, this work aimed to produce a nail lacquer loaded with Amphotericin B (AmB) and evaluate its performance. The AmB-loaded nail lacquer was produced and preliminarily characterized. An AmB quantification method was developed. Stability, drug release, permeability and anti-Candida activity assays were conducted. The analytical method validation met the acceptance criteria. The drug loading efficiency was 100% (0.02 mg/g of total product), whereas the AmB stability was limited to ≅ 7 days (≅ 90% remaining). The nail lacquer displayed a drying time of 187 s, non-volatile content of around 20%w/w, water-resistance of approximately 2%w/w of weight loss and satisfactory in vitro adhesion. Moreover, the in vitro antifungal activity against different Candida spp. strains was confirmed. The AmB release and the ex vivo permeability studies revealed that AmB leaves the lacquer and permeates the nail matrix in 47.76 ± 0.07% over 24 h. In conclusion, AmB-loaded nail lacquer shows itself as a promising extemporaneous dosage form with remarkable anti-Candida activity related to onychomycosis.

scholarly journals Synthesis and Activity of New Schiff Bases of Furocoumarin

2020 ◽  
Vol 26 (1) ◽  
pp. 176-184
Author(s):  
Huijun Xie ◽  
Chao Niu ◽  
Zeyang Chao ◽  
Nuramina Mamat ◽  
Haji Akber Aisa
Keyword(s):  
Animal Models ◽  
Amphotericin B ◽  
Molecular Mechanism ◽  
Schiff Bases ◽  
Positive Control ◽  
Excellent Performance ◽  
Activation Rate ◽  
Antibacterial Spectrum ◽  
Better Than

AbstractFurocoumarins, such as 8-MOP, are the most common medications used to relieve the symptoms of vitiligo clinically. Some furocoumarins also showed excellent performance in an anti-bacterial assay. This paper describes the synthesis of a series of novel Schiff bases (6a-6k), and their promotion in melanogenesis and anti-bacterial properties were studied in vitro.The pigment production of B16 cells and bacterial inhibition ring assay were applied for the bioactivity of 6a-6k. According to the results, a stronger promotion on pigment content was observed, when six compounds co-cultured with cells, compared with positive control (8-MOP). Significantly, compound 6k (237%) as the most active was found to increase the amount of melanin more than 1.7 times compared with 8-MOP activation rate (136%). All the compounds could moderately retard C. albicans growth. Interestingly, aldehyde 5, which possessed a broader antibacterial spectrum, showed the highest inhibition against C. albicans as well and much better than the positive control (Amphotericin B).Studies of 6k in animal models of vitiligo and related molecular mechanism are presently under way, with the aim of discovering an anti-vitiligo leading compound.

Use of spectrophotometric reading for in vitro antifungal susceptibility testing ofAspergillusspp.

1999 ◽  
Vol 45 (10) ◽  
pp. 871-874 ◽  
Author(s):  
Eric Dannaoui ◽  
Florence Persat ◽  
Marie-France Monier ◽  
Elisabeth Borel ◽  
Marie-Antoinette Piens ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Susceptibility Testing ◽  
Clinical Laboratory ◽  
Antifungal Susceptibility ◽  
Reference Method ◽  
Antifungal Susceptibility Testing ◽  
Aspergillus Species ◽  
National Committee ◽  
Broth Microdilution Method

A comparative study of visual and spectrophotometric MIC endpoint determinations for antifungal susceptibility testing of Aspergillus species was performed. A broth microdilution method adapted from the National Committee for Clinical Laboratory Standards (NCCLS) was used for susceptibility testing of 180 clinical isolates of Aspergillus species against amphotericin B and itraconazole. MICs were determined visually and spectrophotometrically at 490 nm after 24, 48, and 72h of incubation, and MIC pairs were compared. The agreement between the two methods was 99% for amphotericin B and ranged from 95 to 98% for itraconazole. It is concluded that spectrophotometric MIC endpoint determination is a valuable alternative to the visual reference method for susceptibility testing of Aspergillus species.Key words: antifungal, susceptibility testing, Aspergillus, spectrophotometric reading.

scholarly journals Surface-Engineered Dendrimeric Nanoconjugates for Macrophage-Targeted Delivery of Amphotericin B: Formulation Development andIn VitroandIn VivoEvaluation

2015 ◽  
Vol 59 (5) ◽  
pp. 2479-2487 ◽  
Author(s):  
Keerti Jain ◽  
Ashwni Kumar Verma ◽  
Prabhat Ranjan Mishra ◽  
Narendra Kumar Jain
Keyword(s):  
Drug Release ◽  
Amphotericin B ◽  
Human Erythrocytes ◽  
Antileishmanial Activity ◽  
Cell Uptake ◽  
Antiparasitic Activity ◽  
Content Type ◽  
Drug Localization

ABSTRACTThe present study aimed to develop an optimized dendrimeric delivery system for amphotericin B (AmB). Fifth-generation (5.0G) poly(propylene imine) (PPI) dendrimers were synthesized, conjugated with mannose, and characterized by use of various analytical techniques, including Fourier transform infrared spectroscopy (FTIR),1H nuclear magnetic resonance (1H-NMR) spectroscopic analysis, and atomic force microscopy (AFM). Mannose-conjugated 5.0G PPI (MPPI) dendrimers were loaded with AmB and evaluated for drug loading efficiency,in vitrodrug release profile, stability, hemolytic toxicity to human erythrocytes, cytotoxicity to and cell uptake by J774A.1 macrophage cells, antiparasitic activity against intracellularLeishmania donovaniamastigotes,in vivopharmacokinetic and biodistribution profiles, drug localization index, toxicity, and antileishmanial activity. AFM showed the nanometric size of the MPPI dendrimers, with a nearly globular architecture. The conjugate showed a good entrapment efficiency for AmB, along with pH-sensitive drug release. Highly significant reductions in toxicity toward human erythrocytes and macrophage cells, without compromising the antiparasitic activity of AmB, were observed. The dendrimeric formulation of AmB showed a significant enhancement of the parasiticidal activity of AmB toward intramacrophagicL. donovaniamastigotes. In thein vitrocell uptake studies, the formulation showed selectivity toward macrophages, with significant intracellular uptake. Further pharmacokinetic and organ distribution studies elucidated the controlled delivery behavior of the formulation. The drug localization index was found to increase significantly in macrophage-rich organs.In vivostudies showed a biocompatible behavior of MPPIA, with negligible toxicity even at higher doses, and promising antileishmanial activity. From the results, we concluded that surface-engineered dendrimers may serve as optimized delivery vehicles for AmB with enhanced activity and low or negligible toxicity.

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