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F C Odds

Publications and source records attributed to F C Odds.

At least 109 records · Page 6Linked to original sources
PubMed1988

Characterization of Candida isolates from pediatric burn patients.

To provide more detailed information about Candida epidemiology and pathogenesis in pediatric burn patients, Candida isolates from 113 patients collected over 3 years were identified at the species level and the serotypes and biotypes of the C. albicans isolates were determined. A total of 85% of the patients were colonized or infected by C. albicans, 18% by C. tropicalis, and 11% by C. parapsilosis. Although colonization or infection often was found at multiple sites and times, 87% of the patients were colonized or infected by only one Candida species or strain; the other 13% showed multiple colonizations or infections, some of which occurred simultaneously at the same site. C. albicans biotyping determined the tolerance of the isolates to pH (pH 1.4) and salt; flucytosine, borate, and safranine resistance; and ability to produce proteinase and assimilate urea, sorbose, and citrate; results are expressed as three-digit numbers. For isolates from three different anatomical sites, the distribution of the nine biotype characteristics was similar in all cases but one. Significantly more fecal than wound or throat isolates were resistant to safranine. Sixty-four different serotype-biotype combinations were found in the 96 patients with C. albicans infections or colonizations. Twenty-nine percent of all C. albicans isolates had the partial biotype -57, while 20 of the 96 patients had specifically serotype B, biotype 557 colonizations or infections. Eleven patients had the B557 infection when admitted; nine patients acquired the yeast in-house. Thirty percent of the C. albicans isolated from 23 adult patients at a nearby hospital also showed the -57 biotype pattern, suggesting that C. albicans isolates expressing this biotype are either extremely prevalent in nature or are more virulent than other C. albicans isolates.

Bacterial Typing Techniques↗
PubMed1987

Epidemiology of vaginal Candida infection: significance of numbers of vaginal yeasts and their biotypes.

The prevalence, quantity and biotypes of vaginal yeasts were determined for 1082 randomly selected nonpregnant patients attending two genitourinary medicine clinics. The overall yeast prevalence was 22.1% with a geometric mean of 40 and a median of 75 yeast colonies per positive isolate (on 5-cm Petri dishes). There was no statistically significant variation in prevalence, quantity or biotype of yeasts with the patients' age, season of the year, stage of the menstrual cycle, recent antibiotic history, contraceptive use or main diagnosis (excluding candidosis). A clinical score for Candida infection, based on symptoms of pruritus and signs of Candida vulvovaginitis, showed significant variation with the prevalence and quantity of yeast isolates. Unequivocal clinical evidence of candidosis was strongly associated with high concentrations of vaginal yeasts. There was also some association between certain groups of Candida albicans biotypes and the clinical score. These observations reemphasize the need for consideration of both clinical and mycological factors in establishing a diagnosis of vulvovaginal Candida infection. It is suggested that isolation of fewer than 10 yeast colonies from a vaginal swab is usually unlikely to indicate an infection requiring treatment.

Age Factors↗
PubMed1987

Disseminated Candida infection syndrome in heroin addicts--dominance of a single Candida albicans biotype.

Among 21 intravenous heroin abusers with cutaneous and ocular manifestations of disseminated Candida infection, a single C. albicans strain type (serotype A, biotype 153/7) was isolated from skin lesions in 14 cases. This suggests that central contamination of the heroin with C. albicans is less likely to be the source of infection than an endogenous source, and that one particular strain type is either better adapted than others to grow in the lemon juice used as a heroin solvent, or more likely than others to cause the specific pathology seen in these patients.

Adult↗
PubMed1987

Candida infections: an overview.

The range of human infections caused by the yeast Candida albicans and a handful of related species is considerable. They range from relatively trivial conditions such as oral and genital thrush to fatal, systemic superinfections in patients who are already seriously ill with other diseases. Interest in Candida infections, and in C. albicans in particular, has become huge in recent years as fatal infections have become more prevalent and new Candida-based pathologies have been recognized. There is now even a large pseudoscientific cult based on the notion that chronic allergy to Candida can cause all sorts of common illnesses. The medical importance of Candida infections and the scientific value of C. albicans as a model for fungal cellular development have stimulated enormous advances in our understanding of the epidemiology of candidosis, pathogenesis of the disease, and the genetics and biochemistry of C. albicans.

Candida↗
PubMed1987

Growth of pathogenic Candida isolates anaerobically and under elevated concentrations of CO2 in air.

Individual isolates of seven potentially pathogenic yeast species in the genus Candida all grew to some extent in Eagle's minimal essential medium including serum under elevated concentrations of CO2 and in anaerobic gas jars. The C. glabrata and C. tropicalis isolates had the highest anaerobic growth rates and yields, the C. guilliermondii and C. parapsilosis isolates had the lowest, and the C. albicans, C. krusei and C. pseudotropicalis isolates gave intermediate growth rates and yields. The same relative abilities to grow anaerobically were seen when the seven isolates were cultured in liquid and on agar formulations of a peptone-glucose broth and two media containing Yeast Nitrogen Base.

Aerobiosis↗
PubMed1987

[Recent advances in the biology of Candida].

There has been enormous progress in our understanding of biological processes in pathogenic Candida species, particularly in the case of C. albicans. Yeast taxonomists have continued to discover the sexual affinities of several members of the genus, although the sexual stage of C. albicans itself remains as elusive as ever. Genetically, C. albicans has been proved to be a diploid with balanced lethal mutations. It is likely to become a popular object of study for transposable genetic elements: recent research in the USA has demonstrated its ability to alter its phenotype at a very high frequency. Phenotypic switching is a property that may be associated with the relative virulence of the species. There is evidence for substantial phenotypic alteration of the cell surface of C. albicans in infected tissues in vivo, which may explain some of the pathological aspects of Candida infection. The best known of the "phenotypic switches" in C. albicans is its ability to transform from budding yeast cells into hyphae. Although the precise mechanisms of this change remains undiscovered, molecular and cell biological approaches to the problem are beginning to reveal many of the processes involved.

Candida↗
PubMed1986

Improved method for estimation of azole antifungal inhibitory concentrations against Candida species, based on azole/antibiotic interactions.

Low, reproducible minimal inhibitory concentrations against Candida species, with sharp, precise end points in complex media were achieved for imidazoles (clotrimazole, econazole, miconazole, tioconazole and ketoconazole) and triazoles (fluconazole, itraconazole, vibunazole, ICI 153066) by including in the test medium antibacterial antibiotics that bind to the 80S eukaryotic ribosome and inhibit protein synthesis, i.e. blasticidin, cycloheximide, doxycycline, neomycin and gentamicin. The presence of these antibiotics reduced MICs, on average, by 50- to 250-fold. Other protein synthesis inhibitors (rifampicin, erythromycin, lincomycin, clindamycin, chloramphenicol and fusidic acid) were not effective, and the antibiotics did not affect MICs for Aspergillus species. The low azole MICs were in close agreement with MICs obtained in a defined, tissue culture-based medium lacking added antibiotics.

Anti-Bacterial Agents↗
PubMed1986

Antifungal effects of fluconazole (UK 49858), a new triazole antifungal, in vitro.

Fluconazole is a novel triazole antifungal intended for oral treatment of superficial and systemic mycoses. In tests done in standard mycological media, the compound had minimal inhibitory concentrations against pathogenic Candida species that were usually in excess of 100 mg/l. By contrast, its 'relative inhibition factors' against Candida species (calculated from areas under the antifungal dose-response curves) were of the same order as those of other imidazole and triazole antifungal agents. Against pathogenic Aspergillus species and dermatophytes, the mean relative inhibition factors were the highest so far recorded for an azole antifungal, indicating a relatively weak inhibitory activity against these fungi. Fluconazole inhibited branching and hyphal development in C. albicans at concentrations as low as 10(-6) M (0.3 mg/l), but miconazole and ketoconazole were still active in these tests at concentrations 100 times lower than this. The new antifungal did not suppress ATP concentrations in C. albicans spheroplasts, in common with other weakly lipophilic azole antifungals. This overall poor activity of fluconazole in vitro corresponds badly with its high activity in animal models of mycoses in vivo, and provides more evidence for the unreliability of tests with azole antifungals in vitro as predictors of potential efficacy in vivo.

Adenosine Triphosphate↗
PubMed1986

Development of Candida albicans hyphae in different growth media--variations in growth rates, cell dimensions and timing of morphogenetic events.

In six liquid culture media, all of which stimulated Candida albicans to grow in the hyphal form, the rates of hyphal extension and increase in cellular ATP concentration, hyphal diameters, times of evagination of hyphae, times of septum formation and positions of septa in the hyphae appeared to vary independently. There were no discernible associations between properties such as length or volume of hyphal compartments at the time of septation and temporal parameters of hyphal growth. The results suggest that growth environment influences many of the processes contributing to hyphal development, but that these processes are not necessarily interrelated.

Adenosine Triphosphate↗
PubMed1986

Consistency of protein patterns in Candida albicans during hyphal septum and branch formation.

Candida albicans was grown in its hyphal form in five different media and in the presence of two concentrations of ketoconazole, and in its yeast form in one medium. Polyacrylamide gel electrophoresis patterns of proteins obtained by disruption of the fungal cells at different times around the stages of septum formation and branch initiation revealed no differences in intracellular protein composition related to growth conditions or time. Autoradiography of proteins labelled with [35S1]-methionine similarly revealed no differences in protein composition related to growth conditions or time. These findings suggest either that septum formation and branch initiation proceed independently of synthesis of new proteins or that proteins related to these processes are synthesized too transiently or in amounts too small to be detected under the conditions of the experiments.

Autoradiography↗
PubMed1985

Outbreak of systemic Candida albicans in intensive care unit caused by cross infection.

The first documented outbreak of systemic candidosis shown to be due to cross infection with a particular strain of Candida albicans is reported. Over nine months in an intensive care unit 13 patients developed definite and one probable systemic candidosis. Twenty five further patients had superficial candidal infections. The strain that caused the outbreak (serotype A, morphotype A1, biotype 0/(1)5 5/7) was responsible for all the cases of systemic candidosis acquired in the intensive care unit, 11 (44%) of the superficial candidal infections in the unit, and 17% of candidal infections outside the unit but in the same hospital. The strain was also isolated from oral swabs taken from four nurses working in the unit and the hands of one of these nurses. Two out of 17 nurses were shown to have acquired the strain on their hands when examined immediately after nursing systemically infected patients. No environmental source could be identified. The strain also showed enhanced survival in handwashing experiments and was relatively resistant to Hibiscrub. Management of patients with systemic candidosis might include measures to prevent cross infection and handwashing with disinfectants that are active against candida.

Adult↗
PubMed1985

Effects of imidazole- and triazole-derivative antifungal compounds on the growth and morphological development of Candida albicans hyphae.

Six azole-derivative antifungal compounds affected several aspects of Candida albicans hyphal development with only a relatively small degree of inhibition of growth rate, measured in terms of ATP concentration, whereas amphotericin B and 5-fluorocytosine affected morphology only when they also substantially inhibited fungal growth rate. At 10(-8) M, all the azoles tested inhibited branch formation by C. albicans hyphae. At 10(-7) M and higher concentrations, clotrimazole and miconazole strongly suppressed emergence of new hyphal outgrowths from parent yeast cells, whereas ICI 153066 and itraconazole had little effect on this phenomenon and ketoconazole and tioconazole had intermediate effects. At the highest concentrations tested (10(-5) M) hyphal development was ultimately arrested by the azole compounds and the fungus grew predominantly in the form of budding yeast cells; however, none of the azole antifungals prevented initial emergence of an apparently normal germ tube. The antifungals only exerted their morphological effects when they were present in the culture medium: removal of the compounds after exposure of C. albicans to them led to reversion to normal growth.

Amphotericin B↗