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Biomedical subjects

R W Sparks

Publications and source records attributed to R W Sparks.

10 recordsLinked to original sources
PubMed1984

Oxidation of 7-ethoxycoumarin and conjugation of umbelliferone by intact, viable epidermal cells from the hairless mouse.

Intact, viable (greater than 80%) epidermal cells were isolated from the hairless mouse. These cells metabolized 7-ethoxycoumarin (7-EC) to umbelliferone ( UMB ) (3 pmol/min/10(6) cells) and UMB to the sulfate and glucuronide conjugates (1 pmol/min/10(6) cells). The rate of oxidation in intact cells compared well with that in disrupted cells with added NADPH, but conjugation proceeded more rapidly in disrupted cells with added cofactors, due to a combination of "activation" of the UDP-glucuronosyltransferase, and to a limitation of activity by the concentration of UDP-glucuronic acid in the intact cells. Pretreatment of the animals with 5,6-benzoflavone resulted in a 5-fold increase in the rate of oxidation, and a 2-fold increase in both the rate of conjugation and the intracellular concentration of UDP-glucuronic acid. UDP-glucuronic acid concentration in isolated cells increased during incubation with glucose, and was regenerated to a steady-state concentration on incubation of cells with UMB . Pretreatment of animals with 5,6-benzoflavone decreased the percentage of metabolite conjugated (from 30% to 15%), whereas adding an inhibitor of oxidation, ellipticine, to cells isolated from pretreated animals, increased the percentage of metabolite conjugated (from 15% to 40%). Sulfation of UMB was almost undetectable, except at very low concentrations (less than 10 nM) of substrate. Thus, glucuronidation of UMB in epidermal cells may be limited by UDP-glucuronic acid availability; sulfation in the epidermis may contribute little to the conjugation of UMB ; and greater than 70% of the products of 7-EC oxidation in the skin may remain unconjugated.

Animals↗
PubMed1978

Sexual attitudes, behavior and satisfaction for able-bodied and disabled participants attending workshops in human sexuality.

Since 1973, Sexual Attitude Reassessment (SAR) Workshops have been conducted for persons with physical handicaps, health care professionals and interested members of the community. Although reassessment of personal sexual attitudes is the primary objective of the workshops, several closely related objectives have emerged: (1) evaluation of the impact of the experience on changing both sexual attitudes and behaviors; (2) evaluation of the sexual satisfaction and problem areas of participants with particular reference to persons with physical disabilities; and (3) provision of an institute-wide catalyst for initiating programs and services based on newly identified unmet needs. This article presents data from 15 workshops with emphasis on comparing the sexual attitudes, behavior and satisfaction of the able-bodied and the disabled participants. Of the 650 participants, 98 (15%) were disabled and of this group approximately 75% had spinal cord injury. Comparison of pre- and post-workshop responses to sexual attitude scales showed similar and significant changes on four of nine scales for both the able-bodied and disabled groups. Analysis of sexual behavior and satisfaction by physical status revealed that the disabled participants were less active than the able-bodied participants although both groups reported similar percentages of satisfaction (38 and 41% respectively) with their current level of sexual activity. Lack of partners was cited most frequently by both groups as the major reason for dissatisfaction with current sexual status. Implications of these findings are discussed with regard to sexual counseling and areas of further research.

Adult↗
PubMed1976

Method: melodic intonation therapy for aphasia.

Melodic intonation therapy (MIT), a method developed to assist the adult aphasic regain verbal communication, is presented with step-by-step procedures and suggestions. Also described is the type of patient for whom the technique appears most successful.

Aphasia↗
PubMed1976

Human sexuality: an interdisciplinary program for health care professionals and the physically disabled.

The central feature of a program in human sexuality for health care professionals and persons with physical disabilities developed at the Texas Institute for Rehabilitation and Research (TIRR) is a 2 1/2-day Sexual Attitude Reassessment (SAR) Workshop. Although the content of this Workshop has many features in common with ones used elsewhere, its organization, financing, and development are relatively unique. Based in a small, specialty hospital in the South, it is a low-budget, largely self-supporting program run by an extradepartmental, multidisciplinary staff. Evaluations of 12 workshops involving over 500 disabled and ablebodied participants are compared with similar data reported in the literature along with information (before and after the workshop) concerning the participants' attitudes, behavior, and satisfaction regarding various sexual activities. There were programmatic, institutional, and community problems unique to developing this program, but it has unusual potential for personal and staff development, intrainstitutional team building and broader community service.

Attitude of Health Personnel↗
PubMedDate not supplied

7-ethoxycoumarin O-deethylation activity in viable basal and differentiated keratinocytes isolated from the skin of the hairless mouse.

Epidermal cells in suspension were prepared from the skin of hairless mice by digestion of skin strips with pronase. The viability of cells in such suspensions was routinely greater than 75%. Fractions enriched in different cell types were prepared from the original cell suspensions using metrizamide gradients and elutriation techniques. These fractions were studied histologically and enzymically. The cells of greater size both were more differentiated and had higher xenobiotic metabolizing enzyme activities. Also increasing in parallel with cell size were parameters such as protein to DNA ratios. Lowest in all respects were basal cells (size, enzyme activities, protein/DNA ratios, etc.). The present techniques seem superior to previously described methods for isolating skin cells for study of xenobiotic metabolisms and possible distribution of these metabolisms in different cell types.

Animals↗