[The Ehlers-Danlos and Marfan syndromes in young children]. / Les syndromes d'Ehlers-Danlos et de Marfan chez le jeune enfant.

Early diagnosis of Ehlers-Danlos and Marfan syndromes in children is illustrated by personal case histories. EDS type IV was suspected in a 3 years old child on the basis of minor clinical signs with positive familial history. Detection of a collagen type III defect in cultured skin fibroblasts confirmed the diagnosis. Using a restriction site polymorphism associated with the structural gene for human type III collagen (COL3A1), tight linkage was found between the polymorphic allele and the clinical expression of the disease. The diagnosis of Marfan syndrome was suspected in a 12 years old girl and her 2 years old brother on the basis of major clinical signs and confirmed after measurement of body proportions and echographic examination. Further biochemical and molecular investigations were not informative. The new therapeutic perspectives in the two syndromes are briefly discussed.

Anticandidal activities of terconazole, a broad-spectrum antimycotic.

Terconazole is a new triazole ketal derivative with broad-spectrum in vitro and in vivo antifungal activities. This study further characterizes the effects of terconazole in vitro on yeast cell growth, viability, and morphology. Terconazole inhibited the growth of Candida albicans ATCC 44859 in a concentration-related manner, but with modest effects noted at levels from 10(-8) to 10(-5) M when the yeast was grown on media favoring the cell form. The inhibitory potency of terconazole on yeast cell viability varied with the strain and species of Candida tested. The susceptibility of C. albicans ATCC 44859 to terconazole was markedly enhanced when the yeast was grown on Eagle minimum essential medium, which favors mycelium formation. The effects of terconazole on the morphology of yeast cells (grown on Eagle minimum essential medium) were shown by phase-contrast and electron microscopy. There is a progression of changes, from loss of mycelia formation at 10(-8) M terconazole through complete necrosis at 10(-4) M.

Site of action of low dose ketoconazole on androgen biosynthesis in men.

Ketoconazole inhibits testosterone biosynthesis in men, but the exact site of its action on the androgen pathway remains to be established. To examine this question, we measured several steroids in the androgen and glucocorticoid pathways in normal men before and after receiving either a single dose of 200 mg ketoconazole or placebo in a cross-over randomized trial. Total and free plasma testosterone fell to levels 60% below basal within 4-8 h (P less than 0.02 in all) and then returned to control concentrations by 24 h after drug administration. The transient alterations of plasma testosterone correlated well with ketoconazole blood levels, which peaked at 2 h and fell exponentially thereafter. A compensatory increase in plasma LH at 24 h in the drug but not placebo group was consistent with the decrease in plasma testosterone. The levels of plasma androstenedione paralleled those of testosterone in the ketoconazole-treated subjects. In marked contrast, plasma 17 alpha-hydroxyprogesterone increased at 4-8 h (all P less than 0.02) before returning to basal values at 24 h. This rise in precursor with fall in product steroid implicated an effect of ketoconazole on the C17-20 lyase enzyme. This conclusion was supported by the highly significant increase in the ratio of plasma 17 alpha-hydroxyprogesterone to androstenedione observed between 2 and 24 h after drug administration. The effect of ketoconazole at this dose level appeared relatively specific, since no decrements in plasma cortisol or 11-desoxycortisol were found. During chronic administration of 200 mg ketoconazole daily, decrements of plasma testosterone 2-4 h after drug administration were minimal and documented only by paired comparisons within subjects but not by unpaired tests between normal men and men receiving drug. The lack of major effects on testosterone levels long term at this dosage probably explain why few androgen-related side effects with this drug were previously reported. Ketoconazole, therefore, represents another compound with relatively selective effects on a cytochrome P-450-mediated steroid hydroxylation step, namely that involved with C17-20 lyase.

Mode of insertion of miconazole, ketoconazole and deacylated ketoconazole in lipid layers. A conformational analysis.

The conformation of three imidazole derivatives, miconazole, ketoconazole and deacylated ketoconazole (R 39 519) inserted in a lipid layer was calculated using a procedure of conformational analysis. For each imidazole derivative all probable conformers were inserted into a dipalmitoyl phosphatidylcholine (DPPC) monolayer. Miconazole maintains its two dichlorophenyl groups in the hydrophobic phase whereas the imidazole moiety is orientated in the hydrophilic phase. Ketoconazole orientates its dichlorophenyl group in the hydrophobic phase whereas its acylated piperazine moiety is orientated towards the hydrophobic region. Deacylation inverses completely the orientation of the compound. The most probable conformer of R 39 519 is inserted in the lipid layer with its piperazine moiety orientated towards the aqueous phase. The inversion increases the area occupied per drug molecule from 30 A2 for ketoconazole to 90 A2 for R 39 519 equal to the mean area occupied per miconazole molecule and higher than that occupied per DPPC molecule (60 A2). Such a conformation should result in a destabilizing effect of miconazole and R 39 519; this was proved using differential scanning calorimetry.

Synergism of the antimicrobial agents miconazole, bacitracin and polymyxin B.

The antibacterial activity of a combination of miconazole with bacitracin against Staphylococcus epidermidis or Staphylococcus aureus, was greater than the sum of the effects observed with the two drugs independently. Since no uptake changes were observed, this synergism may originate from a combined effect of miconazole and bacitracin on the biosynthesis of the carrier lipid, undecaprenyl-phosphate, resulting in an impairment of cell wall integrity. The synergism between these drugs and polymyxin B may be due to an increased accessibility of the cell membrane to polymyxin B. Miconazole and bacitracin, alone or in combination, are completely inactive against Escherichia coli. Since polymyxin B disturbs the permeability barrier and stimulates the uptake of miconazole, the synergism of polymyxin B, miconazole and bacitracin may originate from the ability of miconazole and bacitracin to penetrate the bacterial membranes in the presence of polymyxin B.

The mechanism of action of the new antimycotic ketoconazole.

Ketoconazole is one of the new members of the imidazole series with a broad-spectrum antifungal profile. Although sharing its basic active principles with the other imidazoles, ketoconazole obtains its superior in vivo activity mainly from its good oral absorption and its lower degree of inactivation once absorbed. Its selective toxicity for yeasts and fungi is found to be primarily linked to the inhibition of ergosterol biosynthesis and to interference with other membrane lipids. In vitro growth studies revealed that ketoconazole's activity was more pronounced against the invasive morphogenetic form than against the saprophytic form of Candida albicans, which at least partly explains its prominent in vivo potency. At extremely low concentrations (10 ng/ml-1) ketoconazole prevents the development of the very form that is responsible for the expression of clinical symptoms. In contrast to other imidazoles, ketoconazole's action on the morphogenesis of the organism is not influenced by serum. The synergistic action with host defense cells, as demonstrated in culture systems, is another inherent property of this drug and may have a great impact on the eradication of systemic fungal infections. These effects of ketoconazole have been studied in a variety of fungal organisms with the aid of phase-contrast, scanning, and transmission electron microscopy in order to characterize ketoconazole's profile in comparison to the other imidazole derivatives.

The interaction of miconazole and ketoconazole with lipids.

Staphylococcus aureus can be protected by unsaturated unesterified fatty acids against the growth inhibitory effects of miconazole and ketoconazole observed at concentrations greater than 10(-6) M and greater than 10(-5) M, respectively. Miconazole's fungicidal activity is partly antagonized by oleic acid. However, the effect of ketoconazole on the viability of Candida albicans was not affected by this fatty acid. Cytochrome oxidase and ATPase activities are more sensitive to miconazole (10(-5) M) than to ketoconazole (greater than 10(-4) M) and also liposomes are more susceptible to lysis induced by miconazole. Using differential scanning calorimetry it is shown that high concentrations of miconazole shift the lipid transition temperature of multilamellar vesicles to lower values without affecting the enthalpy of melting. Ketoconazole induces a broadening of the main transition peak only. It is suggested that miconazole changes the lipid organization without binding to the lipids, whereas ketoconazole is localized in the multilayer without having an important direct effect on the lipid organization. The results indicate that miconazole, and to a lesser extent ketoconazole, at doses that can be reached by topical application only, interfere with a third target (the two others are ergosterol synthesis and fatty acid elongation plus desaturation). It is hypothesized that the induced change in lipid organization may play some role in miconazole's topical antibacterial and fungicidal activity, whereas it does not seem to play a significant role in ketoconazole's activities.

The pharmacokinetics of mebendazole and flubendazole in animals and man.

A sensitive and specific radioimmunoassay procedure was developed for mebendazole and flubendazole enabling a more thorough study of the systemic absorption and pharmacokinetic behaviour of the drugs. In rats, plasma levels of oral and subcutaneous mebendazole were about 10 times higher than those of flubendazole. The pro-drug R 34 803 showed levels of metabolically formed flubendazole similar to those found for mebendazole. Intramuscular flubendazole in dogs, injected for 5 consecutive days, produced sustained fairly high plasma levels for at least 6 weeks after the last dose. The absorption of oral flubendazole in man was markedly enhanced when the drug was taken together with a meal. A 20-times higher dose, however, produced only an increase by 1.4 of the plasma levels and AUC-values, indicating that the absorption of flubendazole is limited by the extremely poor solubility of the drug in the contents of the gastrointestinal tract.

Chemotherapy for larval echinococcosis in animals and humans: report of a workshop.

Mebendazole, its fluorine analogue flubendazole, and other benzimidazole derivatives are active against many gastrointestinal and tissue-stage helminths. This article reviews the published literature and proceedings of a workshop on the use of benzimidazoles against larval echinococcosis (hydatid disease). Orally administered high doses (30-50 mg/kg body weight) of mebendazole given daily for 20-90 days to rodents or sheep infected with larval Echinococcus granulosus cause damage of destruction of the cyst wall, loss of cyst fluid, and death of protoscolices. Similar treatment of rodents infected with E. multilocularis with mebendazole, flubendazole, fenbendazole, and albendazole for 60-300 days leads to reduction of weight, inhibition of growth and the metastases formation of E. multilocularis tissue, and to prolonged host survival time although the metacestodes are not killed. Mebendazole or flubendazole treatment of human patients infected with E. granulosus is followed by subjective improvement in most, and evidence of regression of cysts in some; in other patients, cysts continue to grow or have been proven viable even after several months of high-dose mebendazole therapy. In patients infected with E. Multilocularis, the progressive course of the disease appeared to be arrested, but treatment apparently did not kill the parasite. Side effects of some patients have included allergic reactions, alopecia, and reversible neutropenia. Some possible reasons for different responses to treatment include inadequate plasma drug absorption from the gut and age, condition, and location of cysts. Many remaining questions concerning the risk versus benefits of mebendazole therapy can be answered only through controlled clinical trials.

Ketoconazole (R 41 400) in the treatment of dermatophyte infections: a clinical, mycological, and morphological study.

Ketoconazole (100 mg, orally, once daily) was investigated in nine patients with extensive dermatophyte infections. After treatment ranging between one week and three months, clinical cures (healing of lesions and negative cultures) were observed in all cases. In vitro growth of Trichophyton rubrum, T. mentagrophytes, and T. verrucosum isolated from infected skin scales were completely inhibited by concentrations of ketoconazole of 10 microgram/ml and above. No evidence for the development of drug resistance was obtained from regular in vitro sensitivity tests.

The activity of ketoconazole in mixed cultures of leukocytes and Candida albicans.

A system is described which allows the semi-quantitative investigation of the interaction between Candida albicans and leukocytes in culture with and without the addition of chemotherapeutic agents. Both polymorphonuclear leukocytes and macrophages avidly engulfed added yeast cells. However, they did not succeed in eradicating the fungus even when only 450 yeast cells were added to 3 X 10(6) leukocytes. This is probably due to several factors, including the decline in the functiontional capacity of the leukocytes with time in culture. The major way for the fungus to escape intracellular killing, however, seems to be the switch to the mycellial form in the presence of leukocytes. Engulfed yeasts produce germ tubes, grow out of the leukocytes and form hyphae which are much more resistant to the lytic action of the leukocytes. The leukocytes become necrotic through their interaction with the mycelia. Ketoconazole, a potent, orally active systemic antifungal agent inhibited the growth of C. albicans and completely suppressed the formation of mycelia in culture at very low concentrations (0.01 microgram ml-1). It was toxic to the leukocytes themselves only at 100 microgram ml-1. Addition of ketoconazole (10 (10-1.01 microgram ml-1) to mixed cultures of leukocytes and C. albicans allowed complete elimination of the fungus, probably because the leukocytes could easily remove the remaining yeast cells. The data show the usefulness of the system in the search for systemic antifungals and provide a possible explanation for the efficacy of ketoconazole in vivo.

In vitro and in vivo effects of the antimycotic drug ketoconazole on sterol synthesis.

Ketoconazole, an orally active antimycotic drug, is a potent inhibitor of ergosterol biosynthesis in Candida albicans when added to culture media which support yeast or mycelial growth or to cultures containing outgrown mycelium. This inhibition coincides with accumulation of sterols with a methyl group at C-14 and can thus be attributed to an interference with one of the reactions involved in the removal of the 14 alpha-methyl group of lanosterol. When administered to rats infected with C. albicans, ketocanazole also inhibits fungal synthesis of ergosterol. A six-times-higher dose is required to effect cholesterol synthesis by rat liver.