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Biomedical subjects

F Parker

Publications and source records attributed to F Parker.

At least 91 records · Page 5Linked to original sources
PubMed1984

Immunostimulating hexapeptide from human casein: amino acid sequence, synthesis and biological properties.

A hexapeptide obtained from human casein by enzymatic digestion has been purified, sequenced and synthesized; its structure is: Val-Glu-Pro-Ile-Pro-Tyr. In vitro this hexapeptide stimulates the phagocytosis of opsonized sheep red blood cells by murine peritoneal macrophages. Administered intravenously to adult mice, it enhances the resistance to infection with Klebsiella pneumoniae.

Adjuvants, Immunologic↗
PubMed1984

Anatomy of the aortic root.

A variety of operations are now being done on the aortic root. To make it easier to understand the aortic root, a schematic diagram of its anatomy is presented, along with a description of the procedures that are being performed and an illustrative case report of repair of a recurrent perivalvular leak through a right ventricular incision.

Aorta↗
PubMed1984

Glucagonoma syndrome: in vitro evidence that glucagon increases epidermal arachidonic acid.

A 63-year-old white woman with perioral dermatitis, a sore tongue, and an erythematous dermatosis in the inframammary and perineal regions underwent surgical removal of a pancreatic glucagonoma. The patient's plasma and pooled normal human plasma containing Sigma glucagon were fed to human keratinocyte cultures and increased arachidonic acid levels by 300% and 200%, respectively, when compared to pooled normal human plasma with no added commercial glucagon. These experiments suggest that glucagon may increase inflammatory mediators such as arachidonic acid and its metabolites in the epidermis, causing the skin lesions seen in the glucagonoma syndrome.

Adenoma, Islet Cell↗
PubMed1983

Autonomic innervation of the skin in primary erythermalgia.

We observed the autonomic nerve plexuses in the skin of an erythermalgic patient and a normal individual using the methods of acetylcholinesterase (AChE) histochemistry, catecholamine histofluorescence, and electron microscopy. The density of both AChE-positive and catecholamine-containing nerve terminals in the periarterial and sweat glandular plexuses was greatly reduced in the erythermalgic foot skin compared with those in unaffected skin from the same patient and in the foot skin of a normal individual. Ultrastructurally, the terminal axons containing either agranular (cholinergic) or small dense-cored (adrenergic) vesicles were present in the periarterial and periglandular regions of the erythermalgic skin, but the occurrence of these nerve terminals in the involved skin appeared to be much reduced in frequency compared with uninvolved skin and the skin of a normal individual.

Acetylcholinesterase↗
PubMed1982

Ketoconazole in griseofulvin-resistant dermatophytosis.

The efficacy of ketoconazole was evaluated in twenty patients with chronic dermatophyte infections who had failed to clear with griseofulvin therapy. Trichophyton rubrum was the causative organism in nineteen of the patients, and Trichophyton mentagrophytes in one patient. Three of twelve organisms tested showed in vitro resistance to griseofulvin. Duration of infection ranged from 2 to 28 years. Patients received 200 to 400 mg of ketoconazole daily for periods up to 8 months. In addition, patients were followed for 5 months post-therapy to monitor recurrences. Clearing was seen clinically as early as 2 weeks, and by 18 weeks all patients showed marked improvement or clinical clearing, though only six achieved complete mycologic cure. Improvement followed a predictable sequence of sites, with lesions of the trunk healing first, followed by hands, feet, and finally, nails. After 8 months, though all patients showed proximal nail clearing, onychomycosis persisted in thirteen of twenty affected sites. By 5 months post-therapy, four of six patients who had achieved clearing of skin and nails showed recurrences. No significant side effects were observed during therapy, though rare, apparently idiosyncratic cases of hepatotoxicity have been reported. Ketoconazole is an affective therapeutic agent for griseofulvin-resistant dermatophytosis. Apparent cures may subsequently recur after discontinuation of therapy.

Adult↗
PubMed1982

Diet-induced systemic lupus erythematosus (SLE) in primates.

Ten adult, female cynomolgus macaques were randomly assigned to two equal groups: (1) semipurified diet (SPD); and (2) SPD with 45% ground alfalfa seed (AS). Both groups were studied at monthly intervals after 5 mo on their respective diets. Control animals had a mean hematocrit (Hct) of 43 +/- 2%, negative antiglobulin (AG), antinuclear antibody (ANA) and LE cell tests. Mean values for C3 and C4 were 309 +/- 47 mg/dl and 35 +/- 7 mg/dl, respectively. Mean serum binding to radiolabeled double stranded deoxyribonucleic acid (dsDNA) was 1.9 +/- 0.2%. Three of five animals fed AS developed signs of an SLE-like illness characterized by AG-positive anemia (lowest Hct 30%), positive ANA (highest titer greater than 1:15, 360; rim pattern) and elevated anti-dsDNA binding (highest 96%) with variable degrees of hypocomplementemia. One animal had granular deposition of immunoglobulin and complement at the dermal-epidermal junction of clinically normal skin the presence of immune complex-induced glomerulonephritis.

Animals↗
PubMed1981

The biology of pigmentation.

The many factors involved in the normal pigmentation of human skin are highly complex involving anatomic, biochemical, and genetic aspects of melanocytes in the skin and the influence of UV light and various hormones on the melanocytes. It is probably more than just coincidence that the melanocytes, which are of neurogenic origin, are so responsive to several trophic hormones produced in the brain (pituitary). Understanding of the various factors involved in the normal pigmentary process is crucial to explaining the many alterations and anomalies in human pigmentation.

Adrenocorticotropic Hormone↗
PubMed1976

Distinctive features in speech pathology: phonology or phonemics?

Distinctive feature is not a unique concept within linguistic theory. It has two distinct bases: phonemic theory and generative theory. Phonemic theory assumes a direct correspondence between distinctive features (the elements of phonemes) and the speech signal. Although this assumption can be shown to be incorrect, it seems to be the one most widely held in speech science. Generative theory, on the other hand, assumes no such direct relation and consequently can account for certain linguistic phenomena that phonemic theory cannot. This theory then seems to be preferable to phonemic theory for a featural analysis of misarticulation. However, there is a problem. Chomsky and Halle's system (generative theory) as it stands does not deal with the link between what it conceives to be the lowest level of linguistic structure (the phonetic matrix) and speech production. Therefore, Chomsky and Halle's distinctive features cannot be applied fruitfully to all instances of misarticulation. The discrepancy that exists between phonological structure and the speech signal must be accounted for in a theory of speech production. This can be accomplished by recognizing a production matrix below the phonetic matrix, where segments are described in terms of production features. The crucial point is that no one-to-one relationship necessarily exists between distinctive features and production features.

Humans↗
PubMed1975

Light and electron microscopic studies on human temporal arteries with special reference to alterations related to senescence, atherosclerosis and giant cell arteritis.

Temporal artery biopsy specimens from 26 patients of various ages with and without giant cell arteritis afforded an opportunity to examine several ultrastructural features of these human muscular arteries, including senescent and atherosclerotic alterations and the fine structural pathology of temporal arteritis. The unusual pathologic features of temporal arteritis were found superimposed on the progressive accumulation of smooth muscle cells, collagen and occasional discrete intimal atherosclerotic plaques in the intima of aging arteries. Two features of giant cell arteritis were conspicuous: first, the accumulation of large numbers of histiocytes and epitheloid and giant cells at the intimal-medial junction and second, fragmentation, degeneration and dissolution of the internal elastic lamina. The close proximity of the granulomatous reaction to the degenerating lamina suggests that these two aspects of the pathologic picture are in some way related, and possible immunologic mechanisms of this relationship are discussed on the basis of the ultrastructural findings.

Aged↗