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Biomedical subjects

R Marks

Publications and source records attributed to R Marks.

At least 469 records · Page 26Linked to original sources
PubMed1978

The effects on normal skin of adhesives from stoma appliances.

The irritancy of 7 adhesive plasters from different ostomy appliances was compared in 30 normal subjects. The adhesives were replaced both daily and weekly over a 21-day period. Using a clinical rating scale, the results slowed that "Stomahesive" had a significantly less irritating effect on the skin than the other plasters, both when removed daily and when removed weekly. The difference between daily and weekly removal reached statistical significance at the end of Weeks 2 and 3, and the results suggest that the nature of the adhesive is more important than the frequency of removal.

Adolescent↗
PubMed1978

Dermatitis herpetiformis--a skin manifestation of a generalized disturbance in immunity.

Detailed investigations on 42 patients with dermatitis herpetiformis (DH) are presented, emphasis being placed on the presence of other disorders having a prominent immunopathogenic basis. These patients and 42 age and sex matched controls were submitted to an extensive clinical and investigative search for the presence of disorders with an immunological basis including the atopic disorders. The findings provided further evidence supporting the association of dermatitis herpetiformis with thyroid disease and pernicious anaemia. A statistically increased incidence of Raynaud's phenomenon and atopy was found in the patients with dermatitis herpetiformis compared to the control group. In addition, of the patients with dermatitis herpetiformis, two had rheumatoid arthritis, two had ulcerative colitis, one had systemic lupus erythematosus and four had splenomegaly. The possible basis for these associations is discussed and it is suggested that dermatitis herpetiformis may be part of a wider spectrum of disease. Genetic linkage and the formation of immune complexes following exposure to a dietary antigen may both be responsible for the disorders associated with DH.

Adult↗
PubMed1978

Quantitative changes in respiratory enzyme activity in premalignant lesions and experimentally irradiated skin.

Chronic exposure of human skin to solar irradiation results in a variety of preneoplastic and frankly neoplastic skin lesions. We have shown that in solar keratoses (SK) and in paralesional skin there is instead of an even distribution of succinic dehydrogenase (SDH) activity a relative decreased activity in the granular cell layer. Furthermore, there is enhancement of the usual concentration of glucose-6-phosphate dehydrogenase (G6PDH) activity in the granular zone as well as an increase in total G6PDH epidermal activity. In the experimental part of this study, six normal volunteer subjects had areas of normally non exposed skin (buttocks) irradiated with a 2 Mean erythema dose of ultra violet light (290--400 nm) on between 3 and 5 occasions per week for 2--6 week periods. The results obtained indicated that the same changes in enzyme activity localization take place in artificially irradiated normally non exposed epidermis as seen in normally exposed skin nearby actinic keratoses. It is suggested that these quantitative changes may be the basis of a model for the study of chronic ultra violet light damage to the epidermis.

Aged↗
PubMed1977

Factors responsible for dermally induced epidermal hyperplasia.

The secondary epidermal hyperplasia seen over some dermal lesions can be experimentally induced in the guinea pig by the intracutaneous injection of carrageenan. This paper documents experiments directed to determining the factors that cause this epidermal reaction. Indomethacin, aspirin and polyphloretin phosphate were found to block the epidermal thickening. "Non inflammatory" stretching of the skin induced by a silastic implant caused an increase in the germinative population but no sustained epidermal hyperplasia. Rubbing into the skin a rubefacient cream produced more epidermal hyperplasia than did the base cream alone. It is suggested that the secondary epidermal hyperplasia from dermal abnormalities is multifactorial in its causation but that prostaglandin release might be involved and that increased blood flow may also play a role.

Animals↗
PubMed1977

The effects of prostaglandins E1 and F2alpha on epidermal growth.

The effects of prostaglandins E1 and F2alpha (PGE1 and PGF2alpha) on the growth of guinea pig epidermis have been studied in vivo. The prostaglandins were injected intradermally into guinea pigs, and tritiated thymidine was injected intraperitoneally prior to sacrifice. The autoradiographic labelling indices (L.I.) were assessed and a significant increase was found 4 h after injection of PGE1 -an effect which lasted for up to 72 h. PGF2alpha injections had no significant effect on the L.I.

Animals↗
PubMed1977

The epidermal response to change in thyroid status.

Epidermal dimensions, replication, and anabolic activity have been studied before and after treatment in 10 patients with thyrotoxicosis and 7 patients with hypothyroidism. Following treatment of thyrotoxicosis there was a significant decrease in epidermal thickness, and also in cell replication as measured by an autoradiographic labeling index technique. The rates of anabolic activity in the epidermis, as estimated by measuring the rates of incorporation of tritiated precursor compounds, were significantly reduced after treatment in the thyrotoxic group. There were increases in these same measurements in the hypothyroid group following treatment although their magnitude was not as great as that seen after treatment of thyrotoxicosis. There was a significant positive correlation between serum triiodothyronine and epidermal thickness, labeling index and proline incorporation, but no correlation could be detected between serum thyroxine iodine and any of the epidermal measurements. These findings indicate that the eidermis changes in structure and activity in thyroid disease, and that the changes are rapidly reversible. Furthermore, the correlations we have found suggest that the receptors for thyroid hormone in human skin are specific for triiodothyronine.

Adolescent↗
PubMed1977

Measurement of skin thickness: a comparison of two in vivo techniques with a conventional histometric method.

Two in vivo techniques which are rapid, inexpensive, and reproducible have been investigated. The first is a standardized radiological (xerographic) technique which we have shown is capable of detecting small degrees of dermal atrophy after the application of topical corticosteroid preparations for only one month. The second technique employs the Harpenden Skinfold Caliper used in an unconventional manner so as to exclude subcutaneous fat. We have shown that this too is capable of detecting dermal atrophy from the application of topical corticosteroids and that there is a strong correlation between the two techniques (r = 0.82, p less than 0.001). Histometric techniques, on the other hand, give inaccurate and erroneous results for dermal thickness.

Administration, Topical↗
PubMed1977

Measurement of intracorneal cohesion in man using in vivo techniques.

Measurement of intracorneal cohesion in vivo should provide quantitative information concerning the process of esquamation. In this investigation three techniques have been employed to measure the internal binding forces within the stratum corneum in vivo. The first technique, cohesography, directly measures the force required to remove stratum corneum of partial thickness from a known area of skin. Sex and site differences were detected using this method. A second technique employs a surfometer to measure the surface contours of the internal face of skin surface biopsies. Quantitative assessment of surfometer tracings reflects both internal structure of stratum corneum and its cohesive property. Positive correlations were found using these two techniques on the forearms of 16 normal subjects. A scrub technique has also been used which can deliver a controllable and measurable stimulus to the skin surface to release corneocytes. Counting the number of corneocytes released provides a further measure of internal cohesion of the stratum corneum but the results did not correlate with the other two techniques. It is suggested that the use of all three techniques might provide a profile of the cohesive property of the stratum corneum.

Adolescent↗
PubMed1977

Vascular reactions to histamine and compound 48/80 in human skin: suppression by a histamine H2-receptor blocking agent.

1 The ability of a specific competitive histamine H2-receptor antagonist, cimetidine, to inhibit vascular responses to histamine in human skin provides new evidence that skin blood vessels possess histamine H2 receptors. 2 Simultaneous systemic administration of cimetidine and chlorpheniramine (an H1-receptor antagonist) was more effective than either drug alone in inhibition of the erythematous reaction both to exogenous histamine, and endogenous histamine secreted by skin mast cells in response to compound 48/80. 3 These results suggest that combined therapy of histamine-mediated skin diseases included urticaria and dermatitis using a combination of H1- and H2-histamine receptor antagonists may be more effective than either class of drug alone.

Adult↗
PubMed1977

Actinic keratoses and the epidermis on which they arise.

The appearance of the epidermis and epidermal autoradiographic labelling indices were compared in actinic keratoses and paralesional skin in seventeen patients after injection of tritiated thymidine. The skin on the buttock area was also studied as a "non-sun exposed" control. Labelling indices obtained from skin removed after 1 hwere as follows: actinic keratoses 17-4%; paralesional skin 11-2%; buttock skin 5-4%. Many of the epidermal cells in the keratoses that incorporated tritiated thymidine were bizarre and not restricted to the basal or suprabasal regions but were scattered through the thickness of the epidermis. Paralesional skin also showed epidermal thickening and cytological abnormalities including the formation of multinucleate epidermal cells. These findings suggest that the development of actinic keratoses takes place in epidermis that is itself abnormal. The changes suggest that there is a gradual stepwise progression of sun damage epidermis via the clinically obvious keratosis to squamous cell epithelioma.

Autoradiography↗
PubMed1977

Novel techniques for the estimation of intracorneal cohesion in vivo.

Desquamation is the result of loss of cohesion between horny squames. This study is concerned with the in vivo measurement of intracorneal cohesion using three new techniques. A new instrument, the cohesograph, directly measures the force (g) required to distract a known area of partial thickness of stratum corneum in vivo. Sex and site differences were detected with this method. A surfometer was employed to measure the surface contours of the internal face of skin surface biopsies and when this measurement of the surface irregularity was compared to the 'cohesograph' reading for the same sites in 16 normal individuals a significant positive correlation of r=0-79 was found between the two sets of results. It is therefore suggested that the surfometer provides indirect measure of horny layer cohesion. Desquamation has also been estimated by using a modified 'scrub technique'. The scrub apparatus used is able to deliver a controlled stimulus to the skin surface to release horny cells. The light absorbance at 400 nm of corneocyte suspensions was measured and found to correlate well (r=0-96) with the numbers of squames released. It is suggested that the three techniques used in conjunction provide a profile of stratum corneum cohesion in vivo.

Adult↗
PubMed1977

Is there a relationship between lupus erythematosus and lichen planus?

Three patients showing features of both lupus erythematosus and lichen planus are described together with their histological, immunofluorescence and other investigative findings. The similarities between lupus erythematosus and lichen planus are discussed and it is suggested that these may be the result of common pathophysiological pathways.

Adult↗