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Query: UMLS:C0847097 (acidity)
 15,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We used six candidal strains (two Candida albicans and one each of four other species) to study the effects of test conditions on the activity of SCH 39304 compared with that of fluconazole in broth macro- and microdilution assays. Increasing the inoculum from 10(2) to 10(5) yeasts per ml raised the MICs for all isolates up to greater than 512-fold. In contrast, results with a 50% turbidimetric endpoint (50% inhibitory concentration; IC1/2) varied no more than twofold. Similar effects were seen with fluconazole, and both drugs were found to have an associated delay in onset of action. Acidity was found to increase both MICs and IC1/2s. Other effects were observed among four synthetic media, but a consistent pattern was not identified. Incubation temperatures of 37, 35, and 30 degrees C yielded equivalent results. Broth microdilution IC1/2s against most of 40 isolates of C. albicans were 0.31 microgram/ml +/- fourfold for SCH 39304 and 0.16 microgram/ml +/- twofold for fluconazole. Treatment of experimental candidiasis in rats with SCH 39304 and fluconazole resulted in 50% effective doses of 0.33 and 0.49 mg/kg per day, respectively. In contrast, another C. albicans isolate, previously identified as resistant to other azoles, had IC1/2s of 20 micrograms of SCH 39304 per ml and, in vivo, a 50% effective dose of 2.25 mg/kg per day. We conclude that the in vivo efficacy of SCH 39304 correlates with MIC results when broth macrodilution testing is performed with a small inoculum and with IC1/2 results which are independent of inoculum size.
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PMID:In vitro susceptibilities of yeasts to a new antifungal triazole, SCH 39304: effects of test conditions and relation to in vivo efficacy. 255 Dec 15

Hormonal contraceptives, most of which contain norethindrone and norethynodrel combined with estrogen, maintain the body in a state of "artificial pregnancy" and can cause hormonal, vascular, metabolic, and neurolgic side effects similar to the effects seen in pregnancy. Many of these involve the skin. Herpes gestationis is a herpetiform dermatitis with vesicular and bullous eruptions which is triggered by high levels of progesterone and prolactin. Melasma, a dark brown hyperpigmentation, is frequently seen in women taking oral contraceptives. Progesterone activity changes the biochemistry and pH of the skin and sebacious glands, thereby contributing to eruptions of acne vulgaris. Contraceptive pills have been found to increase the incidence of genital candidiasis. Withdrawal from contraceptive pills is often associated with alopecia. Estrogenic substances increase the sensitivity of the skin to light and induce telangiectasia. Oral contraceptives, as well as many other drugs, have been associated with erythema nodosum. Creams, foams, jellies, diaphragms, pessaries and Nonoxynol-9 cause a phenomenon similar to contact dermatitis but with deeper ulcerations due to the acidity of the iritant chemicals.
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PMID:Pharmaceutical effect of contraceptive pills on the skin. 297 37

Among 3,501 individuals receiving endoscopic examination for the upper digestive tract, 41 were found to have esophageal candidiasis including 17 malignancies, 14 immunological disorders, 4 diabetes mellitus, 7 other underlying diseases and 7 apparently healthy subjects. The diagnosis was made either by brushing of the esophagus or by histological examination of the biopsied specimen. Systemic invasion of fungi was observed mainly in patients with malignancy involving the hematopoietic system, and most of them had been treated by corticosteroids, antibiotics or anticancer agents. Although complications associated with esophageal candidiasis are rare, it is emphasized that those patients with malignancy as well as impared immunity should be carefully examined for esophageal candidiasis, in order to prevent the fungi from developing invasive candidiasis. It should be noted that a few cases of gastric ulcer treated by H2 blocker revealed esophageal candidiasis, suggesting that decrease of gastric acidity might be one of the factors involved in this pathological condition.
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PMID:Esophageal candidiasis. 318 63

Candida albicans was established in large numbers throughout the gut after one oral challenge in the germ-free and in the conventional mouse. Of the strains tested, only the germ-free ND 1 mouse appeared to be susceptible to infection, and this was confined to the stomach mucosa; lesions contained large numbers of hyphal and mycelial forms with blastospores. These forms were also seen in the gut of resistant germ-free ND 4 mice after challenge. Only budding yeast forms were seen in the gut contents from conventional animals. The concentration of sulfhydryl-containing compounds was decreased in the stomach contents from germ-free mice. The stomach tissue of conventional animals seemed to be more acidic than that of germ-free animals, and association of C. albicans with conventional mice neutralized some of this acidity. E(h) values of contents from the gut of unchallenged mice were usually higher in conventional than in germ-free animals; after challenge, the E(h) in both groups decreased. Some reciprocal effects of intestinal microorganisms and host are discussed in relation to intestinal candidiasis.
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PMID:Growth and invasiveness of Candida albicans in the germ-free and conventional mouse after oral challenge. 597 Apr 61

Candida infection of mild gastric ulcers was detected by gastric biopsy in 6 patients aged from 67 to 82 years. Filaments and spores were located in the connective tissue or submucosa in 3 cases and in the false membrane in the other 3. No predisposing cause was found in 5 patients. Chemical study of the gastric secretion was performed in all patients under maximal pentagastrin stimulation and showed normal acidity. The addition of amphotericin B to the anti-ulcerous treatment seems to have helped the ulcer to heal.
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PMID:[Candida infection of gastric ulcers. 6 cases (author's transl)]. 725 20

We adapted a rat model of gastrointestinal candidiasis for studies of in vivo gastric colonization with Candida albicans. Whereas normal rats cleared a single intragastric inoculum of 5 x 10(6) C. albicans from the stomach within 4 hours, rats pretreated with chloramphenicol and gentamicin achieved stable gastric colonization for at least 5 days after administration of this inoculum. We next used this model to study host modifications hypothesized to alter gastric colonization. A first group received dilute HCl 4 hr before yeast inoculation, to induce acute superficial gastric erosions; another group was treated with glucocorticosteroid beginning 12 days before yeast inoculation; and another group received famotidine therapy beginning 3 days before yeast inoculation, to neutralize gastric acidity. Recovery of yeasts from stomachs was significantly different from the control group only in rats treated with steroids; greater colonization was found in the rats so treated. In a final group of experiments, we attempted to inhibit in vivo gastric colonization with yeasts by preincubation of yeasts in vitro with a polyclonal antiserum raised in rabbits against heat-killed C. albicans. We were not able to demonstrate inhibition of gastric colonization by preincubation with this antiserum in this model system.
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PMID:Gastric colonization with Candida albicans. 832 93

The combination of tools such as time-kill assay with subsequent application of mathematical modeling can clarify the potential of new antimicrobial compounds, since minimal inhibitory concentration (MIC) value does not provide a very detailed characterization of antimicrobial activity. Recently, our group has reported that the 8-hydroxy-5-quinolinesulfonic acid presents relevant antifungal activity. However, its intrinsic acidity could lead to an ionization process, decreasing fungal cell permeability. To overcome this potential problem and enhance activity, the purpose of this study was to synthesize and evaluate a novel series of hybrids between the 8-hydroxyquinoline core and sulfonamide and to prove their potential using broth microdilution method, obtaining the pharmacodynamic parameters of the most active derivatives combining time-kill studies and mathematical modeling and evaluating their toxicity. Compound 5a was the most potent, being active against all the fungal species tested, with low toxicity in normal cells. 5a and 5b have presented important antibacterial activity against Staphylococcus aureus strain. The EC50 values obtained by combination of time-kill studies with mathematical model were similar to those of MIC, which confirms the potential of compounds. In addition, these derivatives are non-irritant molecules with the absence of topical toxicity. Finally, 5a and 5b are promising candidates for treatment of dermatomycosis and candidiasis.
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PMID:Rapid tools to gain insights into the interaction dynamics of new 8-hydroxyquinolines with few fungal lines. 3045 Jul 82

Candida glabrata is a major cause of candidiasis and the second most frequent opportunistic yeast pathogen. Its infectious and antifungal mechanisms are globally regulated by the transcription systems of pathogenic fungi. In this study, we reconstructed the genome-scale transcriptional regulatory network (TRN) of C. glabrata, consisting of 6634 interactive relationships between 145 transcription factors and 3230 target genes, based on genomic and transcriptomic data. The C. glabrata TRN was found to have a typical topological structure and significant network cohesiveness. Moreover, this network could be functionally divided into several sub-networks, including networks involving carbon, nitrogen, growth-associated metabolic profiles, stress response to acidity, hyperosmosis, peroxidation, hypoxia and virulence. Furthermore, by integrating the genome-scale metabolic model of C. glabrata, six essential metabolites and eight related enzymes were systematically selected as drug targets. Overall, elucidation of the genome-scale TRN of C. glabrata has expanded our knowledge of the contents and structures of microbial regulatory networks and improved our understanding of the regulatory behaviors of growth, metabolism and gene expression programs in response to environmental stimuli.
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PMID:Computational inference of the transcriptional regulatory network of Candida glabrata. 3103 21