PubMed Health⌕ Search

Biomedical subjects

D Pierce

Publications and source records attributed to D Pierce.

At least 37 records · Page 2Linked to original sources
PubMed1990

Large-scale structural changes in the sarcoplasmic reticulum ATPase appear essential for calcium transport.

Model refinement calculations utilizing the results from time-resolved x-ray diffraction studies indicate that specific, large-scale changes (i.e., structural changes over a large length scale or long range) occur throughout the cylindrically averaged profile structure of the sarcoplasmic reticulum ATPase upon its phosphorylation during calcium active transport. Several physical-chemical factors, all of which slow the kinetics of phosphoenzyme formation, induce specific, large-scale changes throughout the profile structure of the unphosphorylated enzyme that in general are opposite to those observed upon phosphorylation. These results suggest that such large-scale structural changes in the ATPase occurring upon its phosphorylation are required for its calcium transport function.

Biological Transport, Active↗
PubMed1989

Prevention of myocardial disease in JCR:LA-corpulent rats by running.

The JCR:LA-corpulent rat is a congenic strain that, if homozygous for the cp gene, is obese with a very low-density lipoprotein hyperlipidemia and is insulin resistant. The male corpulent rats develop atherosclerotic lesions of the major arteries and myocardial lesions. Corpulent and lean male rats were induced through mild food restriction to run intensively (approximately 6,000 m/day) from 6 wk to 6 mo of age. Food restriction, especially when coupled with running, lowered all classes of lipids in the whole serum of corpulent rats. The principal changes in lipid concentrations were in the very low-density lipoprotein fraction. Food restriction caused a significant drop in fasting insulin levels of corpulent rats and decreased beta-cell hyperplasia. Both effects were more marked in the running animals. There was a significant decrease in myocardial lesion frequency in the food-restricted corpulent rats and an absence of lesions in the running rats. The results indicate that intensive physical activity can largely correct the lipid abnormalities and insulin resistance of this atherosclerosis-prone strain, and these changes are associated with inhibition of the disease process. However, moderate food restriction has similar effects, and the greater effects seen with intensive running may simply reflect an effectively more severe metabolic restriction in the presence of the exercise.

Animals↗
PubMed1987

Factors affecting the level of kanamycin resistance in transformed sunflower cells.

A 230 base pair DNA segment containing the sequences 5' to the 700 to 750 nucleotide (nt) transcript 7' (ORF 3; RF Barker, KB Idler, DV Thompson, JD Kemp 1983 Plant Mol Biol 2: 335-350) of the octopine tumor inducing plasmid pTiA6 has been isolated. This region has (a) 180 base pairs of DNA upstream of the TATA box, (b) the start of RNA synthesis, and (c) the entire 5' untranslated region of the gene. We have fused this presumed promoter fragment to the neomycin phosphotransferase II (NPTII) gene from Tn5 in a plant expression cassette. After recombination into a tumor inducing plasmid delivery plasmid, this cassette confers selectable kanamycin resistance to transformed sunflower cells. Removal of the out-of-frame ATG in the 5' leader sequence of the NPTII gene by two different modifications increased both the levels of NPTII enzyme activity and the ID(50) for kanamycin in the tumor cells. The promoter region of the transcript 7 gene gives levels of kanamycin resistance equivalent to the nopaline synthase promoter and octopine synthase promoter when used in the same constructions and assayed in the same tissues.

Journal Article↗
PubMed1987

Induction of voluntary prolonged running by rats.

The rat is widely used in studies of the metabolic and physiological effects of physical exercise. The most commonly used form of exercise is running on treadmills or mechanically driven running wheels. Rats will not voluntarily run significant distances, under normal circumstances. If rats are exposed to running wheels with food freely available, only very limited activity normally occurs. When rats with access to a running wheel are restricted to a fixed amount of food, presented once per day, consistent running occurs. The running is spontaneous and very sensitive to the amount of food provided. Six 6-wk-old rats of 197 g mean body wt were induced to run for 139 days. The distance run increased rapidly over a 20-day initial period on a food supply of 15 g/day (vs. 19.5 g/day consumption by sedentary controls). From day 20 to day 139 the mean distance run was described by the regression equation distance (m/day) = 10,410 - 37.9 X days. Food provided was varied according to distance run, ranging from 15 to 18 g/day, and was normally 17.5 g/day. Thus a food deprivation of 10% of normal consumption will result in mean distances run of approximately 8,000 m/day. The use of pair-fed control animals without access to a wheel allows the conduct of experiments to test the effects of chronic long-distance running. The running is spontaneous; thus the technique avoids the complications accompanying techniques that force running.

Animals↗
PubMed1987

The possible effects of a change to master's entry level in occupational therapy.

One of the most challenging debates facing the profession of occupational therapy centers on whether or not the standard for entry level into the field should be upgraded. The occupational therapy baccalaureate degree has been viewed as too limited in scope and professional training, and the master's degree has been forwarded as the standard for entry into the profession. However, upgrading the entry level standard raises several questions. This study considered 25 areas that would be affected by upgrading the entry level from the baccalaureate to the master's level in occupational therapy and in related health professions. A model was developed to provide a framework for analyzing how a change in entry level will affect the current status of occupational therapy as a profession. Although the parallel material is drawn from other health professions, the considerations are similar to the ones faced by occupational therapy. This comparison is especially important because a major change in entry level education has far-reaching repercussions that must be considered before any groundwork is laid for upgrading educational requirements.

Clinical Competence↗
PubMed1986

Deliberate self-harm: how do patients view their treatment?

The opinions of patients who had caused deliberate self-harm about the attitudes of doctors, nurses, families and others towards their acts were studied. Their views of the attitudes of hospital staff were found to be markedly different from attitudes reported elsewhere by staff themselves. There were no differences between the patients' views of their handling by nurses, families, and others towards their acts were studied. Their views of the attitudes of families were unsympathetic. A significant association was found between repetition of an act of deliberate self-harm and the perception of an unsympathetic attitude within the family.

Adult↗
PubMed1984

Suicidal intent and repeated self-harm.

The value of identifying self-harm patients who repeat with rising suicidal intent is discussed. A study is described measuring changes in intent with repetition by means of an intent scale. Patients repeating once in 5 years scored significantly higher in intent for their second episodes, while multiple repeaters tended to score lower for second episodes. Patients under the age of 35 were most at risk for repetition with increasing intent within 2 years. No correlation emerged between the rise in intent and the time interval between episodes over a 7-year period. The 5-year suicide rate was higher among rising intent repeaters than other cases. These findings are discussed.

Follow-Up Studies↗
PubMed1983

Vesiculopustular eruption of ulcerative colitis.

Many cutaneous disorders that have been described in association with ulcerative colitis (UC), including certain pustular eruptions, probably represent early, evolving lesions of pyoderma gangrenosum (PG). Several nonspecific, often poorly delineated pustular eruptions apparently unrelated to pyoderma gangrenosum have also been reported to occur with ulcerative colitis. A patient had an evanescent, vesiculopustular eruption with a course paralleling that of his UC. Histologic examination of biopsy material from the skin revealed intraepidermal and subcorneal neutrophilic abscess formation and a mixed dermal, perivascular inflammatory cell infiltrate with notable sparing of the follicles. An IgG deposition in a bandlike pattern was identified at the dermoepidermal junction by direct immunofluorescence microscopy. This vesiculopustular eruption may represent a distinct entity or another case or variant of similar pustular eruptions previously described in association with UC.

Adult↗
PubMed1982

Static and time-resolved structural studies of the Ca2+-ATPase of isolated sarcoplasmic reticulum.

X-ray and neutron diffraction studies of oriented multilayers of isolated light sarcoplasmic reticulum (SR) have provided the separate profile structures of the lipid bilayer and the Ca2+-ATPase molecule within the membrane profile to approximately 10 A resolution. These studies utilized biosynthetically deuterated SR phospholipids incorporated isomorphously into the isolated SR membranes via exchange proteins. Time-resolved x-ray diffraction studies of these oriented SR membrane multilayers have indicated that significant changes occur in the membrane profile structure within a single turnover of the Ca2+-transport cycle. These studies utilized the flash photolysis of caged ATP to effectively synchronize the ensemble of Ca2+-ATPase molecules in the multilayer, synchrotron x-radiation to provide 100- to 500-millisecond data collection times, and double-beam spectrophotometry to monitor Ca2+ transport in the oriented SR membrane multilayer.

Animals↗
PubMed1980

Neurological complications of cryosurgery.

Among the few serious complications of cryosurgery are neuropathies. Three cases are reported. Prevention of neuropathy from cryosurgery depends upon awareness of the superficiality of the course of certain peripheral nerves in certain anatomic sites and cautious practice or avoidance of cryosurgery in those sites.

Adolescent↗
PubMed1976

Urinary epinephrine and norepinephrine levels in women athletes during training and competition.

Training and competitive epinephrine and norepinephrine levels and proportions were compared in two groups of women athletes to determine whether changes in catecholamine excretion reflect the added mental stress of athletic competition on physical effort. An intercollegiate basketball team and a group of track and field athletes volunteered as subjects. Competitive epinephrine urinary levels were significantly (P less than 0.01) higher than training levels. A concomitant rise in the norepinephrine with an increase in physical effort was observed in both groups of athletes following training sessions as well as after athletic competition. Track and field athletes trying to qualify for an international team exhibited significantly ( less than 0.01) higher epinephrine levels than the team members; thus suggesting that anticipation of competition imposes a mental stress on an athlete. Constant changes in the catecholamine pattern as against a normal work load have yet to be established.

Adolescent↗
PubMed1976

Group treatment format: mixed sexual dysfunctions.

This study reports the rationale and results of a ten-session group composed os six couples with mixed sexual dysfunctions. Dysfunctions included premature ejaculation, primary and situational orgasmic dysfunction, situational impotence, and incompatible sex drives. A variety of pretreatment behavioral and attitudinal measures were administered, including a Life History Questionaire, Sexual Assessment Inventory, Marital Adjustment Scale, and Sexual Interaction, orgasmic attainment, ejaculatory control, and enhanced self-acceptance, particularly for females (SII changes). The consistency between outcome measures was also a noteworthy finding. The results suggest increased use of mixed short-term groups, particularly when cost-effectiveness accountability is important. One contraindication for such groups is, however, severe marital discord, as evidenced by Locke-Wallace mean scores of 80 or less.

Adaptation, Psychological↗
PubMedDate not supplied

Interactions of the chemotaxis signal protein CheY with bacterial flagellar motors visualized by evanescent wave microscopy.

The chemotaxis signal protein CheY of enteric bacteria shuttles between transmembrane methyl-accepting chemotaxis protein (MCP) receptor complexes and flagellar basal bodies [1]. The basal body C-rings, composed of the FliM, FliG and FliN proteins, form the rotor of the flagellar motor [2]. Phosphorylated CheY binds to isolated FliM [3] and may also interact with FliG [4], but its binding to basal bodies has not been measured. Using the chemorepellent acetate to phosphorylate and acetylate CheY [5], we have measured the covalent-modification-dependent binding of a green fluorescent protein-CheY fusion (GFP-CheY) to motor assemblies in bacteria lacking MCP complexes by evanescent wave microscopy [6]. At acetate concentrations that cause solely clockwise rotation, GFP-CheY molecules bound to native basal bodies or to overproduced rotor complexes with a stoichiometry comparable to the number of C-ring subunits. GFP-CheY did not bind to rotors lacking FIiM/FliN, showing that these subunits are essential for the association. This assay provides a new means of monitoring protein-protein interactions in signal transduction pathways in living cells.

Bacterial Proteins↗
PubMedDate not supplied

Evaluating organic compound migration in poly(ethylene terephthalate): a simple test with implications for polymer recycling.

The safety of recycled plastics for food contact use is largely dictated by the ability of post-consumer organic contaminants to absorb into recycled materials and later diffuse from containers made from recycled plastics into the food supply. Diffusion and solubility data for organic contaminants in poly(ethylene terephthalate) (PET) are scarce. An approach for determining permeability constants, diffusion coefficients and solubility constants of slowly migrating contaminants in PET is described. Compounds (neat or in admixture) were heat-sealed in packets made from thin (0.00127 cm) PET films. Packets were placed in containers with GC sampling closures. Headspace (volatile compounds) or an external liquid medium (non-volatile compounds) was analysed for emergence of the compound. Diffusion coefficients were determined from non-steady state diffusion equations, permeability constants were determined from steady state permeation, and solubility constants were calculated from diffusion and permeability values. Diffusion coefficients (25 degrees C) ranged from 10(-9) to < 10(-16) cm2/s. The diffusion coefficient of benzene increased dramatically with concentration. Compounds with high permeation increased the transport rate of slower permeating volatiles.

Conservation of Natural Resources↗
PubMedDate not supplied

A historical cross-disciplinary perspective on the professional doctorate in occupational therapy.

Clinical doctorates are emerging in occupational therapy. By examining the development of clinical doctorates in medicine, dentistry, psychology, pharmacy, nursing, and physical therapy, implications can be drawn for the future of occupational therapy education. These histories offer us a sense of the distinct purpose and curricular structure of the professional doctorate, its successes and problems, its general sequence of unfolding, the political dynamics surrounding it, and the potential it holds for supporting the profession's capacity for service to patients.

Education, Graduate↗