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  1. Article: Carrier effects on biological activity of amphotericin B.

    Brajtburg, J / Bolard, J

    Clinical microbiology reviews

    1996  Volume 9, Issue 4, Page(s) 512–531

    Abstract: Amphotericin B (AmB), the drug of choice for the treatment of most systemic fungal infections, is marketed under the trademark Fungizone, as an AmB-deoxycholate complex suitable for intravenous administration. The association between AmB and deoxycholate ...

    Abstract Amphotericin B (AmB), the drug of choice for the treatment of most systemic fungal infections, is marketed under the trademark Fungizone, as an AmB-deoxycholate complex suitable for intravenous administration. The association between AmB and deoxycholate is relatively weak; therefore, dissociation occurs in the blood. The drug itself interacts with both mammalian and fungal cell membranes to damage cells, but the greater susceptibility of fungal cells to its effects forms the basis for its clinical usefulness. The ability of the drug to form stable complexes with lipids has allowed the development of new formulations of AmB based on this property. Several lipid-based formulations of the drug which are more selective in damaging fungal or parasitic cells than mammalian cells and some of which also have a better therapeutic index than Fungizone have been developed. In vitro investigations have led to the conclusion that the increase in selectivity observed is due to the selective transfer of AmB from lipid complexes to fungal cells or to the higher thermodynamic stability of lipid formulations. Association with lipids modulates AmB binding to lipoproteins in vivo, thus influencing tissue distribution and toxicity. For example, lipid complexes of AmB can be internalized by macrophages, and the macrophages then serve as a reservoir for the drug. Furthermore, stable AmB-lipid complexes are much less toxic to the host than Fungizone and can therefore be administered in higher doses. Experimentally, the efficacy of AmB-lipid formulations compared with Fungizone depends on the animal model used. Improved therapeutic indices for AmB-lipid formations have been demonstrated in clinical trials, but the definitive trials leading to the selection of an optimal formulation and therapeutic regimen have not been done.
    MeSH term(s) Amphotericin B/administration & dosage ; Amphotericin B/pharmacokinetics ; Amphotericin B/toxicity ; Animals ; Aspergillosis/drug therapy ; Blastomycosis/drug therapy ; Candidiasis/drug therapy ; Cell Death ; Cell Membrane/metabolism ; Clinical Trials as Topic/statistics & numerical data ; Coccidioidomycosis/drug therapy ; Cryptococcosis/drug therapy ; Detergents/metabolism ; Drug Carriers/administration & dosage ; Drug Carriers/adverse effects ; Drug Delivery Systems/methods ; Drug Industry ; Histoplasmosis/drug therapy ; Immunity, Active ; Leishmania/drug effects ; Leishmaniasis, Visceral/drug therapy ; Lipoproteins/metabolism ; Mice ; Molecular Structure ; Phospholipids/metabolism ; Rabbits
    Chemical Substances Detergents ; Drug Carriers ; Lipoproteins ; Phospholipids ; Amphotericin B (7XU7A7DROE)
    Language English
    Publishing date 1996-10
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 645015-5
    ISSN 1098-6618 ; 0893-8512
    ISSN (online) 1098-6618
    ISSN 0893-8512
    DOI 10.1128/CMR.9.4.512
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Dwumetyloamid z estru cyjanometylowego kwasu chinolino-3-karboksylowego.

    Brajtburg, J

    Acta poloniae pharmaceutica

    1969  Volume 26, Issue 4, Page(s) 385–386

    Title translation Dimethylamide cyanomethyl from ester of quinoline-3-carboxylic acid.
    MeSH term(s) Acids ; Amides/chemical synthesis ; Chemistry, Pharmaceutical ; Esters ; Quinolines
    Chemical Substances Acids ; Amides ; Esters ; Quinolines
    Language Polish
    Publishing date 1969
    Publishing country Poland
    Document type Journal Article
    ZDB-ID 40045-2
    ISSN 0001-6837
    ISSN 0001-6837
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Molecular basis for the selective toxicity of amphotericin B for yeast and filipin for animal cells.

    Kotler-Brajtburg, J / Price, H D / Medoff, G / Schlessinger, D / Kobayashi, G S

    Antimicrobial agents and chemotherapy

    2004  Volume 5, Issue 4, Page(s) 377–382

    Abstract: Among the polyene antibiotics, many, like filipin, cannot be used clinically because they are toxic; amphotericin B, however, is useful in therapy of human fungal infections because it is less toxic. Both the toxicity of filipin and the therapeutic value ...

    Abstract Among the polyene antibiotics, many, like filipin, cannot be used clinically because they are toxic; amphotericin B, however, is useful in therapy of human fungal infections because it is less toxic. Both the toxicity of filipin and the therapeutic value of amphotericin B can be rationalized at the cellular and molecular level by the following observations: (i) these polyene antibiotics showed differential effects on cells; filipin was more potent in lysing human red blood cells, whereas amphotericin B was more potent in inhibiting yeast cell growth; and (ii) the effects of filipin were more efficiently inhibited by added cholesterol, the major membrane sterol in human cells, whereas the effects of amphotericin B were more efficiently inhibited by ergosterol, the major membrane sterol in yeast. The simplest inference is that the toxicity and effectiveness of polyenes are determined by their relative avidities for the predominant sterol in cell membranes.
    MeSH term(s) Amphotericin B/toxicity ; Animals ; Anti-Bacterial Agents/toxicity ; Antifungal Agents/toxicity ; Drug Interactions ; Erythrocytes/drug effects ; Filipin/toxicity ; Hemolysis/drug effects ; Humans ; Polyenes/pharmacology ; Saccharomyces cerevisiae/drug effects ; Sterols/pharmacology
    Chemical Substances Anti-Bacterial Agents ; Antifungal Agents ; Polyenes ; Sterols ; Amphotericin B (7XU7A7DROE) ; Filipin (87Z59R7D14)
    Language English
    Publishing date 2004-08-10
    Publishing country United States
    Document type Journal Article
    ZDB-ID 217602-6
    ISSN 1098-6596 ; 0066-4804
    ISSN (online) 1098-6596
    ISSN 0066-4804
    DOI 10.1128/AAC.5.4.377
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Affinity of amphotericin B for phosphatidylcholine vesicles as a determinant of the in vitro cellular toxicity of liposomal preparations.

    Jullien, S / Brajtburg, J / Bolard, J

    Biochimica et biophysica acta

    1990  Volume 1021, Issue 1, Page(s) 39–45

    Abstract: Candida albicans and human erythrocytes were treated with liposomal amphotericin B (AmB) obtained by incubation of free AmB with small unilamellar vesicles (SUV) composed of unsaturated fatty acyl chains phosphatidylcholine (egg-yolk PC). Cellular ... ...

    Abstract Candida albicans and human erythrocytes were treated with liposomal amphotericin B (AmB) obtained by incubation of free AmB with small unilamellar vesicles (SUV) composed of unsaturated fatty acyl chains phosphatidylcholine (egg-yolk PC). Cellular effects were determined by changes in the K+ internal content of cells and in the number of colonies formed by fungal cells or as hemolysis, measured as a decrease in haemoglobin retention by erythrocytes. Dose-response curves were obtained by two procedures: either the ratio of AmB to phospholipids was kept constant over the AmB concentration range used (R = 10(-2] or the phospholipid concentration was kept constant (C = 0.2 mM) and the concentration of AmB varied. The liposomal preparations of AmB were as active against fungi as AmB in dimethylsulfoxide but less active (internal K+ changes) or inactive (hemolysis) against erythrocytes. On the other hand the binding of AmB to the SUV, as a function of the AmB concentration, was monitored by circular dichroism, fluorescence and UV absorption, in the two conditions used for the cellular studies. The amount of AmB bound when the total concentration of antibiotic was 2.10(-7) M was very low but increased with concentration and reached 90% at 10(-5) M. In all the assays we used, the anticellular effects could be attributed to the levels of AmB remaining free (unbound to the lipids). The variations of these levels with total AmB concentration could therefore explain the increased selectivity of liposomal AmB in toxicity against fungi and erythrocytes as compared to that of AmB added as a solution in dimethylsulfoxide. Indeed fungal cells are sensitive to low concentrations of AmB in dimethylsulfoxide; at these concentrations, in liposomal preparations, AmB is not bound to phospholipids and therefore as active as if added in dimethylsulfoxide. By contrast erythrocytes are only sensitive to much higher concentrations of AmB in dimethylsulfoxide; at these concentrations AmB is almost totally bound to phospholipids and therefore much less active.
    MeSH term(s) Amphotericin B/administration & dosage ; Amphotericin B/metabolism ; Amphotericin B/pharmacology ; Candida albicans/drug effects ; Dimethyl Sulfoxide/pharmacology ; Dose-Response Relationship, Drug ; Humans ; In Vitro Techniques ; Liposomes/metabolism ; Male ; Phosphatidylcholines/metabolism ; Potassium/metabolism
    Chemical Substances Liposomes ; Phosphatidylcholines ; Amphotericin B (7XU7A7DROE) ; Potassium (RWP5GA015D) ; Dimethyl Sulfoxide (YOW8V9698H)
    Language English
    Publishing date 1990-01-15
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 60-7
    ISSN 1879-2596 ; 1879-260X ; 1872-8006 ; 1879-2642 ; 1879-2618 ; 1879-2650 ; 0006-3002 ; 0005-2728 ; 0005-2736 ; 0304-4165 ; 0167-4838 ; 1388-1981 ; 0167-4889 ; 0167-4781 ; 0304-419X ; 1570-9639 ; 0925-4439 ; 1874-9399
    ISSN (online) 1879-2596 ; 1879-260X ; 1872-8006 ; 1879-2642 ; 1879-2618 ; 1879-2650
    ISSN 0006-3002 ; 0005-2728 ; 0005-2736 ; 0304-4165 ; 0167-4838 ; 1388-1981 ; 0167-4889 ; 0167-4781 ; 0304-419X ; 1570-9639 ; 0925-4439 ; 1874-9399
    DOI 10.1016/0005-2736(90)90381-w
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Comparison of the leishmanicidal activity of fungizone, liposomal AmB and amphotericin B incorporated into egg lecithin-bile salt mixed micelles.

    Ramos, H / Brajtburg, J / Marquez, V / Cohen, B E

    Drugs under experimental and clinical research

    1995  Volume 21, Issue 6, Page(s) 211–216

    Abstract: We compared leishmanicidal activity of five formulations of amphotericin B (AmB). AmB used as Fungizone immediately caused cell lysis, at lower concentrations partial, and at higher concentrations total; the non-lysed cells reassuming growth. AmB ... ...

    Abstract We compared leishmanicidal activity of five formulations of amphotericin B (AmB). AmB used as Fungizone immediately caused cell lysis, at lower concentrations partial, and at higher concentrations total; the non-lysed cells reassuming growth. AmB formulated with egg-lecithin and bile salt at doses equivalent to those of Fungizone was not active, whereas at higher doses it resulted in a delayed but complete inhibition of cell growth. The activity of liposomal AmB was comparable to that of Fungizone. The time of initial leishmanicidal activity of the five formulations tested can be ascribed to the rate of free, monomeric AmB delivered. Features that are characteristic of the anticellular effect of AmB formulated with egg lecithin and bile salts, a delay in activity, a requirement for higher concentration and total inhibition of cell growth, were also noted.
    MeSH term(s) Amphotericin B/administration & dosage ; Amphotericin B/pharmacology ; Animals ; Antifungal Agents/pharmacology ; Bile Acids and Salts/chemistry ; Deoxycholic Acid/pharmacology ; Drug Carriers ; Glycocholic Acid/pharmacology ; Leishmania mexicana/drug effects ; Leishmania mexicana/growth & development ; Liposomes ; Micelles ; Ovum/chemistry ; Phosphatidylcholines/chemistry
    Chemical Substances Antifungal Agents ; Bile Acids and Salts ; Drug Carriers ; Liposomes ; Micelles ; Phosphatidylcholines ; Deoxycholic Acid (005990WHZZ) ; Amphotericin B (7XU7A7DROE) ; Glycocholic Acid (G59NX3I3RT)
    Language English
    Publishing date 1995
    Publishing country Switzerland
    Document type Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 752502-3
    ISSN 0378-6501
    ISSN 0378-6501
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Amphotericin B incorporated into egg lecithin-bile salt mixed micelles: molecular and cellular aspects relevant to therapeutic efficacy in experimental mycoses.

    Brajtburg, J / Elberg, S / Kobayashi, G S / Bolard, J

    Antimicrobial agents and chemotherapy

    1994  Volume 38, Issue 2, Page(s) 300–306

    Abstract: The cellular activities of amphotericin B (AmB) used as Fungizone were compared with those of AmB complexed to either egg lecithin and glycocholate (Egam) or egg lecithin and deoxycholate (Edam). Under conditions in which leakage of K+ from erythrocytes ... ...

    Abstract The cellular activities of amphotericin B (AmB) used as Fungizone were compared with those of AmB complexed to either egg lecithin and glycocholate (Egam) or egg lecithin and deoxycholate (Edam). Under conditions in which leakage of K+ from erythrocytes and cultured L cells treated with Fungizone was almost complete, Egam and Edam containing concentrations of AmB severalfold greater than the concentration of AmB in Fungizone had no effect but retained the ability to decrease the level of retention of K+ in fungal cells. Analysis by absorption and circular dichroism spectroscopy demonstrated that when these formulations containing AmB at concentrations of less than 10(-5) M were added to buffer, the AmB dissociated slowly as monomers from Egam or Edam and dissociated rapidly as a mixture of monomers and self-associated species from Fungizone. We propose that in Egam and Edam, the absence of free AmB in the self-associated form reduces the toxicity of AmB to mammalian cells, whereas the presence of monomeric AmB results in the retention of the antifungal activities of these complexes.
    MeSH term(s) Amphotericin B/administration & dosage ; Amphotericin B/pharmacokinetics ; Amphotericin B/toxicity ; Animals ; Bile Acids and Salts ; Cells, Cultured ; Circular Dichroism ; Drug Carriers ; Drug Stability ; Erythrocytes/drug effects ; Erythrocytes/metabolism ; Fibroblasts/drug effects ; Fibroblasts/metabolism ; Humans ; Lipoproteins/pharmacology ; Mice ; Micelles ; Mycoses/drug therapy ; Phosphatidylcholines ; Potassium/metabolism ; Potassium/pharmacokinetics ; Spectrophotometry ; Therapeutic Equivalency
    Chemical Substances Bile Acids and Salts ; Drug Carriers ; Lipoproteins ; Micelles ; Phosphatidylcholines ; Amphotericin B (7XU7A7DROE) ; Potassium (RWP5GA015D)
    Language English
    Publishing date 1994-02
    Publishing country United States
    Document type Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 217602-6
    ISSN 1098-6596 ; 0066-4804
    ISSN (online) 1098-6596
    ISSN 0066-4804
    DOI 10.1128/AAC.38.2.300
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Treatment of murine candidiasis and cryptococcosis with amphotericin B incorporated into egg lecithin-bile salt mixed micelles.

    Brajtburg, J / Elberg, S / Travis, S J / Kobayashi, G S

    Antimicrobial agents and chemotherapy

    1994  Volume 38, Issue 2, Page(s) 294–299

    Abstract: Amphotericin B (AmB) with deoxycholate (Fungizone) and AmB incorporated into mixed micelles (AmB-mixMs) composed of egg lecithin with glycocholate, deoxycholate, or taurocholate were compared as treatments for murine infections. For mice infected with ... ...

    Abstract Amphotericin B (AmB) with deoxycholate (Fungizone) and AmB incorporated into mixed micelles (AmB-mixMs) composed of egg lecithin with glycocholate, deoxycholate, or taurocholate were compared as treatments for murine infections. For mice infected with Candida albicans, treatment consisted of a single intravenous injection; for mice infected with Cryptococcus neoformans, treatment consisted of two intravenous injections. The maximal tolerated doses of AmB as Fungizone were 1.25 mg/kg of body weight in mice with candidiasis and 2.5 mg/kg of body weight in mice with cryptococcosis. The AmB-mixMs were nontoxic to mice at doses of 80 and 100 mg/kg of body weight and were therapeutically more active than the maximal tolerated dose of Fungizone in both models of infection. However, when Fungizone or AmB-mixMs were administered at equivalent doses of AmB, AmB-mixMs were more active in treating murine candidiasis, whereas Fungizone was more active in treating murine cryptococcosis.
    MeSH term(s) Amphotericin B/administration & dosage ; Amphotericin B/pharmacology ; Amphotericin B/toxicity ; Animals ; Bile Acids and Salts ; Candidiasis/drug therapy ; Cryptococcosis/drug therapy ; Dose-Response Relationship, Drug ; Drug Carriers ; Drug Evaluation, Preclinical ; Female ; Mice ; Mice, Inbred Strains ; Micelles ; Phosphatidylcholines
    Chemical Substances Bile Acids and Salts ; Drug Carriers ; Micelles ; Phosphatidylcholines ; Amphotericin B (7XU7A7DROE)
    Language English
    Publishing date 1994-02
    Publishing country United States
    Document type Comparative Study ; Journal Article ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 217602-6
    ISSN 1098-6596 ; 0066-4804
    ISSN (online) 1098-6596
    ISSN 0066-4804
    DOI 10.1128/AAC.38.2.294
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Concentration dependent dual effect of the monolauryl ester of sucrose on the antifungal activity and absorption spectra of amphotericin B (Fungizone).

    Brajtburg, J / Gruda, I / Daigle, I / Medoff, G

    Biochimica et biophysica acta

    1989  Volume 985, Issue 3, Page(s) 307–312

    Abstract: ... to mammalian cells (Gruda, I., Gauthier, E., Elberg, S., Brajtburg, J. and Medoff, G. (1988) Biochem. Biophys ...

    Abstract A mild detergent, the monolauryl ester of sucrose (LS), at concentrations which ranged from 0.008 to 0.03%, enhanced amphotericin B (AmB) toxicity against Saccharomyces cerevisiae and Cryptococcus neoformans cells. At higher concentrations, 0.06 to 2.5%, LS inhibited AmB effects on these two fungi. We analyzed changes in the absorption spectrum of AmB induced by LS at these two concentration ranges by comparing ratios (R values) of AmB absorbance at 409 nm, the wavelength characteristic of non-aggregated (monomeric) AmB, to absorbance at 328 nm, the wavelength characteristic of aggregated AmB. Low concentrations of LS caused a decrease in R, whereas the higher LS concentrations increased R. Therefore, LS had concentration-dependent dual effects on the antifungal activity of AmB which correlated with shifts in the physical states of AmB. The concentration range of LS required to inhibit the antifungal effects of AmB was about 1000-fold greater than the previously reported concentrations required to inhibit AmB toxicity to mammalian cells (Gruda, I., Gauthier, E., Elberg, S., Brajtburg, J. and Medoff, G. (1988) Biochem. Biophys. Res. Commun. 154, 954-958). This suggests that LS may be a useful agent to decrease AmB toxicity to host cells without affecting the antifungal effects. Moreover, increase in AmB toxicity induced by low concentrations of LS suggests the possibility that synergistic interaction between fatty acid esters and polyene antibiotics may have therapeutic value.
    MeSH term(s) Amphotericin B/pharmacology ; Antifungal Agents/pharmacology ; Dose-Response Relationship, Drug ; Drug Synergism ; Saccharomyces cerevisiae/drug effects ; Spectrophotometry, Ultraviolet ; Sucrose/pharmacology
    Chemical Substances Antifungal Agents ; sucrose monolaurate (05Q7CD0E49) ; Sucrose (57-50-1) ; Amphotericin B (7XU7A7DROE)
    Language English
    Publishing date 1989-11-03
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 60-7
    ISSN 1879-2596 ; 1879-260X ; 1872-8006 ; 1879-2642 ; 1879-2618 ; 1879-2650 ; 0006-3002 ; 0005-2728 ; 0005-2736 ; 0304-4165 ; 0167-4838 ; 1388-1981 ; 0167-4889 ; 0167-4781 ; 0304-419X ; 1570-9639 ; 0925-4439 ; 1874-9399
    ISSN (online) 1879-2596 ; 1879-260X ; 1872-8006 ; 1879-2642 ; 1879-2618 ; 1879-2650
    ISSN 0006-3002 ; 0005-2728 ; 0005-2736 ; 0304-4165 ; 0167-4838 ; 1388-1981 ; 0167-4889 ; 0167-4781 ; 0304-419X ; 1570-9639 ; 0925-4439 ; 1874-9399
    DOI 10.1016/0005-2736(89)90417-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Poszukiwania substancji o działaniu przeciwserotoninowym w grupie pochodnych chinoliny. VI. Amidy kwasu chinolino-3-karboksylowego i chinolilo-3-octowego.

    Kotler-Brajtburg, J

    Acta poloniae pharmaceutica

    1968  Volume 25, Issue 4, Page(s) 383–389

    Title translation Search for antiserotonin substances among quinoline derivatives. VI. Amides of quinoline-3-carboxylic acid quinoline-3-acetic acid.
    MeSH term(s) Acetates ; Animals ; Female ; Nitriles ; Quinolines/chemical synthesis ; Rats ; Serotonin Antagonists ; Uterus/drug effects
    Chemical Substances Acetates ; Nitriles ; Quinolines ; Serotonin Antagonists
    Language Polish
    Publishing date 1968
    Publishing country Poland
    Document type Journal Article
    ZDB-ID 40045-2
    ISSN 0001-6837
    ISSN 0001-6837
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Poszukiwania substancji o działaniu przeciwserotoninowym w grupie pochodnych chinoliny. 3. Pochodne 3-(aminometylo)-chinoliny o zredukowanym pierścieniu heterocyklicznym.

    Kotler-Brajtburg, J

    Acta poloniae pharmaceutica

    1968  Volume 25, Issue 2, Page(s) 117–121

    Title translation Search for quinoline derivatives with antiserotonin effects. 3. Derivatives of 3-aminomethylquinoline with hydrogenated heterocyclic ring.
    MeSH term(s) Heterocyclic Compounds/chemical synthesis ; Quinolinium Compounds/chemical synthesis ; Serotonin Antagonists
    Chemical Substances Heterocyclic Compounds ; Quinolinium Compounds ; Serotonin Antagonists
    Language Polish
    Publishing date 1968
    Publishing country Poland
    Document type Journal Article
    ZDB-ID 40045-2
    ISSN 0001-6837
    ISSN 0001-6837
    Database MEDical Literature Analysis and Retrieval System OnLINE

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