Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022568 (keratitis)
 5,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Chitin, a unique structural polysaccharide found in fungi and arthropods, is not produced by vertebrates. Thus, the potential applications of a specific and sensitive assay for chitin are numerous, including the evaluation of the extent of fungal keratitis. Chitin is a homopolymer of beta (1, 4) linked D-N-acetylglucosamine. We have developed a simple and reproducible assay for chitin and applied it to Candida albicans cultures. The assay involves homogenization of the culture and treatment with 21.1 M KOH to remove soluble materials, including proteins. This base treatment also deacetylates the chitin to the glucosamine polymer, chitosan. Chitosan is hydrolyzed by 0.5 M H2SO4 to glucosamine monomers which are then deaminated by the addition of NaNO2 to the acid solution. The resulting 2,5-anhydromannose is reduced by NaB[3H]4 to 1-[3H] 2,5-anhydromannitol. This radiolabelled sugar is isolated by paper chromatography and quantified via liquid scintillation. The sensitivity of this assay is assessed by comparison of colony forming units (CFU's) with a glucosamine standard. A typical run of the assay detects 53.1 CFU/c.p.m., and 356,000 c.p.m. per nanomole of N-acetylglucosamine. The specificity of the assay is very high because of the unique nature of chitin. This method of chitin determination may be a useful alternative method for future investigations involving the study of fungal infections in mammalian tissues.
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PMID:Development of a chitin assay for the quantification of fungus. 852 98

Likopide (N-acetylglucosamine-(beta 1-4)-N-acetylmuramyl-alanyl-D-isoglutamine) is a synthetic analog of muramylpeptides, characterized by immunomodulating properties and increasing the nonspecific resistance to infections. Seventy patients with ophthalmic herpes were examined, 35 of these were treated with likopide and 35 were administered placebo. Fifty-two of these suffered from stromal keratitis with ulceration and 18 had no ulcers. The trials were carried out by the double blind test with placebo. Likopide was administered orally in 10 mg tablets twice daily according to the following protocol: 3 days of treatment, 3-day interval, and 3-day treatment. All the patients were administered local specific (acyclovir ointment) and general symptomatic therapy. Immunological studies were carried out before and after therapy. Clinical assessment showed a reliably high therapeutic efficacy of likopide, its total value (excellent and good results) being as high as 88.5%. The mean duration of therapy with likopide was 11.4 +/- 0.4 days versus 15.2 +/- 0.9 days in the placebo group. Judging by the recovery criteria (arrest of inflammation, epithelization of the cornea, resorption of corneal infiltration and edema, resorption of iritis) likopide reliably accelerated healing and ensured a higher increase of vision acuity. Likopide reliably decreased the rate of detection of herpes simplex virus antigen in the involved eye conjunctiva in comparison with the placebo group patients (97.1% of negative cases versus 60%). The drug was well tolerated by the patients, no side effects were observed. Skin allergic tests with likopide showed no drug allergies.
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PMID:[Therapy of stromal herpetic keratitis with a new immunomodulator likopide]. 938 37

Free-living amoebae belonging to the genus Acanthamoeba are the causative agents of infections such as amoebic keratitis (AK), granulomatous amoebic encephalitis (GAE) and cutaneous lesions. The mechanisms involved in the establishment of infection are unknown. However, it is accepted that the initial phase of pathogenesis involves adherence to the host tissue. In this work, we analysed surface molecules with an affinity for epithelial and neuronal cells from the trophozoites of Acanthamoeba castellanii. We also investigated the cellular mechanisms that govern the process of trophozoite adhesion to the host cells. We first used confocal and epifluorescence microscopy to examine the distribution of the A. castellanii actin cytoskeleton during interaction with the host cells. The use of drugs, as cytochalasin B (CB) and latrunculin B (LB), revealed the participation of cytoskeletal filaments in the adhesion process. In addition, to identify the proteins and glycoproteins on the surface of A. castellanii, the trophozoites were labelled with biotin and biotinylated lectins. The results revealed bands of surface proteins, some of which were glycoproteins with mannose and N-acetylglucosamine residues. Interaction assays of biotinylated amoebae proteins with epithelial and neuronal cells showed that some surface proteins had affinity for both cell types. The results of this study provide insight into the biochemical and cellular mechanisms of the Acanthamoeba infection process.
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PMID:Biochemical and cellular mechanisms regulating Acanthamoeba castellanii adherence to host cells. 2447 61