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D A Sutton

Publications and source records attributed to D A Sutton.

48 records · Page 3Linked to original sources
PubMed1997

Invasive Nattrassia mangiferae infections: case report, literature review, and therapeutic and taxonomic appraisal.

We report on a case of subcutaneous infection of the arm caused by the coelomycetous fungus Nattrassia mangiferae (formerly Hendersonula toruloidea) in a steroid-dependent diabetic man with chronic obstructive lung disease. The man was a resident of Arizona, where the fungus is known to be endemic on Eucalyptus camaldulensis and on citrus trees. Diagnosis of fungal infection was made by observation of narrow hyphal filaments by histopathology of biopsy specimens and isolation of a fast-growing black mold which demonstrated hyphae and arthroconidia of varying widths typical of the Scytalidium synanamorph (S. dimidiatum). The formation of pycnidia, which at maturity expressed conidia with a central median dark band, allowed for the confirmation of the isolate as N. mangiferae. Remission of the lesions occurred following intravenous therapy with amphotericin B, followed by topical clotrimazole treatment. We use this patient's case report as an opportunity to review the literature on cases of deep infection caused by Scytalidium species, to evaluate the antifungal susceptibilities of a spectrum of Scytalidium isolates, and to review the taxonomy of Scytalidium species isolated from human infections.

Aged↗
PubMed1997

An aberrant variant of Histoplasma capsulatum var. capsulatum.

We studied an aberrant culture of Histoplasma capsulatum var. capsulatum isolated from synovial fluid collected from the right elbow of a patient from Kansas. Colonies on Sabouraud glucose agar and other routine mycological media were glabrous to soft, moist, heaped, deeply folded or convoluted, and orange-brown with a white, irregular margin. Microscopically, hyphae were hyaline, septate, and branched and remained totally devoid of conidiation over a period of 2 years on all mycological media. Conversion to the yeast form was achieved on Pine's medium at 37 degrees C. Colonies at early stages of growth were smooth, moist, pasty, shiny, and orange-brown but soon became wrinkled and slightly raised and produced oval, thin-walled cells measuring 2 to 3 by to 4.5 microns which multiplied by polar budding. The identity of the isolate was further confirmed by utilizing the Accuprobe DNA and the exoantigen test for H. capsulatum var. capsulatum.

DNA Probes↗
PubMed1996

Simple method for detecting fluconazole-resistant yeasts with chromogenic agar.

A method for detecting fluconazole-resistant yeasts was developed that uses chromogenic agar containing fluconazole. Yeasts were plated on media with fluconazole at 0, 8, and 16 micrograms/ml. On media without fluconazole, normal growth of susceptible yeasts (defined as those having a fluconazole MIC of < 8 micrograms/ml) was detected, while fluconazole-containing media suppressed susceptible strains and normal colonies of resistant yeasts (fluconazole MICs of > or = 8 micrograms/ml) were detected. This method was used to screen for resistance in oropharyngeal candidiasis. Isolates having fluconazole MICs of > or = 8 micrograms/ml and < 8 micrograms/ml were correctly predicted in 43 of 45 cultures and 115 of 116 cultures, respectively. This screening method appears to be rapid and sensitive for detection of fluconazole-resistant yeasts.

Agar↗
PubMed1979

Receptor binding studies on A1-(2-nitro-4-trimethylammoniophenyl)insulin.

The results are presented from receptor binding studies and isolated fat cell assays on A1-(2-nitro-4-trimethylammoniophenyl)insulin. In the former tests, the derivative is shown to have properties similar to native insulin and the fat cell assays afford a value of 76 +/- 4%. The importance of a charged, hydrophilic moiety attached at A1-glycine is discussed in the light of the above findings.

Adipose Tissue↗
PubMed1978

Crystalline [A21-desamido]bovine insulin.

[A21-Desamido]insulin is the major product formed during mild acid hydrolysis of bovine insulin at low insulin concentration. The derivative was isolated by standard procedures and its purity established by isoelectric focusing, disc electrophoresis and electrophoresis on cellulose acetate strips. The identity of the acid-transformed derivative was determined as [A21-desamido]insulin by the action of carboxypeptidase A, using conditions under which a C-terminal aspartic acid residue would not be removed. The biological activity of this crystalline derivative was found to be 15.9 units/mg as measured by the mouse convulsion assay.

Amino Acids↗
PubMed1976

Preparation of a crystalline tris-(N-methylpyridinium)-derivative of bovine insulin.

The reaction between 2-chloro-N-methylpyridinium iodide and bovine insulin at pH 8.5 afforded a trisubstituted derivative as main product. Following purification on DEAE-Sephadex A-25, this derivative crystallized from a citrate buffer in the form of large rhombohedra very similar to native insulin. This observation was confirmed by zero-layer X-ray precession photography. Amino acid analysis indicated substitution at the B1-terminus and on two of the four tyrosine residues. In the mouse convulsion assay the derivative showed no biological activity.

Animals↗
PubMed1976

Preparation of a crystalline A1-(2-nitro-4-trimethylammoniophenyl) derivative of bovine insulin.

The reaction of bovine insulin with the hydrophilic reagent 1-fluoro-2-nitro-4-trimethylammoniobenzene iodide at pH 8.2 has been reexamined. From the mixture of products a crystalline derivative substituted at the GlyAl terminus has been isolated. It has been characterized by amino acid analysis, end group analysis, cellulose acetate electrophoresis and sulphitolysis. The derivative has a biological activity (mouse convulsion assay) of 60% relative to insulin.

Animals↗
PubMed1972

Evaluation of 1-fluoro-2-nitro-4-trimethylammoniobenzene iodide, a protein-solubilizing reagent.

The new protein reagent 1-fluoro-2-nitro-4-trimethylammoniobenzene iodide reacts with model amino acids to give derivatives that are very stable to hydrolysis. In a dimethyl sulphoxide-water medium it reacts rapidly (3h) with bovine insulin, and substitution occurs quantitatively at the N-terminal amino groups and at the in-amino groups of lysine residues. Two of the four tyrosine residues react, and it is assumed that these are the exposed groups leaving the buried groups unattacked. Unlike 1-fluoro-2,4-dinitrobenzene and related reagents, it imparts hydrophilic properties to the protein derivative, thus facilitating structural and other studies on the derivative. Circular-dichroism spectra of the modified insulin suggest that no conformational changes have occurred during reaction. These spectra also reveal the presence of an extrinsic Cotton effect at 410nm.

Amino Acids↗
PubMedDate not supplied

Cerebral phaeohyphomycosis caused by a dematiaceous scopulariopsis species.

This report describes a rapidly fatal case of cerebral phaeohyphomycosis in a 33-year-old immunocompetent male. The infection presented as a single large lesion in the deep white matter of one temporal lobe, which was then removed surgically. Histologic features observed in the lobectomy specimen were characterized by perivascular sleeves of mononuclear cells accompanied by hemorrhages. These were reminiscent of acute hemorrhagic leukoencephalitis except for the presence of rare fungal organisms and sparse multinucleated giant cells similar to those occurring in AIDS. During the four days following surgery, a large focus of cerebritis with massive invasion of fungi developed in each centrum semiovale around the ventriculostomy sites. Fungal culture of the brain obtained at autopsy grew an organism consistent with a Scopulariopsis species.

Adult↗