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Biomedical subjects

P S Williamson

Publications and source records attributed to P S Williamson.

15 recordsLinked to original sources
PubMed2002

Neuropeptide Y fails to normalize food intake in zinc-deficient rats.

Zinc deprivation results in decreased and cyclic food intake in rats. We determined the response of zinc-deprived rats to neuropeptide Y (NPY). In a preliminary experiment, rats were fed a low (-Zn; <1 mg/kg) or adequate zinc diet (+Zn; 100 mg/kg) for 4 days. NPY (5 or 10 microg) was then administered via an intracerebroventricular (ICV) cannula and food intake measured for 4 h. NPY stimulated food intake in all rats, but the difference in food intake due to zinc deprivation persisted. In a subsequent experiment, rats were fed the low zinc and adequate zinc diets for 4, 5 or 6 days. Food intake was suppressed in rats fed the low zinc compared to the adequate zinc diet on all of these days. When NPY (10 microg) was administered at the onset of the light cycle, the food intake was approximately 2.5-fold greater regardless of dietary zinc status, but the amount of food consumed by rats fed low zinc was approximately one-half the quantity consumed by NPY-stimulated zinc-adequate rats. NPY administered at the onset of dark failed to stimulate food intake in either dietary group although the total intake difference due to zinc status persisted. ICV administration of 5 nmol of zinc prior to NPY injection failed to correct the food intake response of the zinc-deficient rats. We conclude that the basis of the reduced food intake of zinc-deficient rats does not relate to NPY quantity or release, or to impairment of its signal transduction. There appears to be another undefined factor that limits food intake in zinc deficiency.

Animals↗
PubMed2000

Genetic testing.

Explore the source record for details and available documents.

Confidentiality↗
PubMed2000

Pollination by flies, bees, and beetles of Nuphar ozarkana and N. advena (Nymphaeaceae).

Nuphar comprises 13 species of aquatic perennials distributed in the temperate Northern Hemisphere. The European species N. lutea and N. pumila in Norway, the Netherlands, and Germany are pollinated by bees and flies, including apparent Nuphar specialists. This contrasts with reports of predominant beetle pollination in American N. advena and N. polysepala. We studied pollination in N. ozarkana in Missouri and N. advena in Texas to assess whether (1) there is evidence of pollinator shifts associated with floral-morphological differences between Old World and New World species as hypothesized by Padgett, Les, and Crow (American Journal of Botany 86: 1316-1324. 1999) and (2) whether beetle pollination characterizes American species of Nuphar. Ninety-seven and 67% of flower visits in the two species were by sweat bees, especially Lasioglossum (Evylaeus) nelumbonis. Syrphid fly species visiting both species were Paragus sp., Chalcosyrphus metallicus, and Toxomerus geminatus. The long-horned leaf beetle Donacia piscatrix was common on leaves and stems of N. ozarkana but rarely visited flowers. Fifteen percent of visits to N. advena flowers were by D. piscatrix and D. texana. The beetles' role as pollinators was investigated experimentally by placing floating mesh cages that excluded flies and bees over N. advena buds about to open and adding beetles. Beetles visited 40% of the flowers in cages, and flowers that received visits had 69% seed set, likely due to beetle-mediated geitonogamy of 1st-d flowers. Experimentally outcrossed 1st-d flowers had 62% seed set, and open-pollinated flowers 76%; 2nd-d selfed or outcrossed flowers had low seed sets (9 and 12%, respectively). Flowers are strongly protogynous and do not self spontaneously. Flowers shielded from pollinators set no seeds. A comparison of pollinator spectra in the two Old World and three New World Nuphar species studied so far suggests that the relative contribution of flies, bees, and beetles to pollen transfer in any one population depends more on these insects' relative abundances (and in the case of Donacia, presence) and alternative food sources than on stamen length differences between Old World and New World pond-lilies.

Journal Article↗
PubMed1994

Supportive family members of diabetic adults.

OBJECTIVE: Family members usually become involved during the course of care for a chronic illness. This study identified the diabetic adult's perceived supportive family member(s) and analyzed whether family participation was associated with the diabetic adults' level of metabolic control. METHODS: A telephone survey of 131 diabetic adults was conducted from a family practice residency office asking patients to identify family members participating in their diabetes care and to enumerate specific support activities. Demographic and metabolic control data were abstracted from patient records. RESULTS: Two broad categories of family participation exist. The first is the family health monitor (FHM), or internal "health expert" for the family. The other is the often distinct primary supportive family member; or "helper," defined as a family member who performs at least one supportive task in the care of the illness. Three-fourths of diabetic adults identified an FHM within their families. Eighty-seven percent of FHM's were women, usually adult daughters of diabetic women or wives of diabetic men. Forty-nine percent of diabetic women and 70% of diabetic men also identified a "helper." The most frequent helping tasks involved: dietary issues (48%), medication (23%), general support (15%) and blood sugar monitoring (9%). No relationship emerged between the presence or absence of an FHM or a helper and the level of metabolic control as measured by HbA1C level, which was categorized as "poor" in 55% of the sample. CONCLUSIONS: An FHM or some other helping family member is available to most diabetic adults in our patient population. The mere presence of an available FHM or other potential resource person is not necessarily related to a positive influence on metabolic control.

Adult↗
PubMed1989

The initial presentation of depression in family practice and psychiatric outpatients.

Most reports characterizing the initial presentation of depression are based on patients seen in psychiatric settings. It is not clear whether the difficulty in identifying depression in medical clinic outpatients is due to physician unfamiliarity with the diagnostic criteria or because the psychiatric syndrome is not the same in early, mild cases that present with somatic symptoms. In this study, depressed patients choosing the medical clinic for care presented the same somatic symptoms as nondepressed medical patients. In comparison to depressed patients who presented to the psychiatric clinic, depressed medical patients' chief complaints were more somatic, obscure, and less psychologically focused. Depressed psychiatric patients had more symptoms on a medical review of systems checklist than did medical patients with an equivalent level of depression. When DSM-III criteria were applied, depressed patients from each clinic tended to fulfill the major and minor criteria in a similar pattern. However, the prevalence of depression in the medical setting was much lower and milder than was that presenting to the psychiatry clinic. Once present at a diagnosable stage, however, the syndrome appeared to be the same in both patient groups.

Adult↗
PubMed1988

Long-term body weight fluctuation in an overweight population.

Weight loss programs report such low percentages of overweight subjects who lose weight and maintain the loss that the concern arises whether these results represent anything more than baseline population weight fluctuations. In this study, weights recorded for medical purposes at two clinic visits separated by intervals of 1 to 5 years were analysed for 332 adult patients who were initially at least 20 percent over their ideal body weight. Weight change calculations for this general patient population revealed that 219 (66 percent) had increased in weight by a mean of 5.7 kg, and that 113 (34 percent) had decreased in weight by a mean of 5.3 kg. The 59 patients measured over a 5-year interval showed an 'apparent body weight loss' for 31 percent of this sub-group with a mean decrease of 7.3 kg. Weight loss studies and programs must demonstrate a rate of weight loss maintenance beyond that of a control group before attributing 'weight loss' in a population to any factor other than normal weight fluctuation.

Adult↗
PubMed1988

Health screening examinations: the patient's perspective.

Periodic preventive screening programs will require patient cooperation if they are to be successful. To determine the level of patient interest on a broad scale, 1,788 adult patients were surveyed in 47 family physicians' offices over a statewide area. Seventy percent said they had participated in a screening health checkup in the preceding two years. Nine percent of these patients reported discovering a previously unknown condition as a result of their recent screening examination. The majority of surveyed patients said they would agree to be screened or treated with the complete list of eight suggested procedures for men and ten procedures for women. Rates of patient acceptance of specific health maintenance recommendations ranged from a low of 54 percent for influenza immunization to a high of 91 percent for a blood pressure check. Listing typical costs did not alter the selection rates of patients with insurance coverage compared with those without it. The geriatric age group was the least willing to be screened. Seventy-two percent of patients indicated that they wanted to discuss at least one wellness topic with their physician. Overall, most patients are willing to participate in the concept of a periodic health maintenance examination as recommended to them by their physician.

Adult↗
PubMed1988

Patient perceptions and weight loss of obese adults.

Little is known about the relative importance of self-image, physician attention to obesity, weight-loss program participation, exercise, self-motivation, and nutrition knowledge in the process of weight loss. Fifty-six obese adults who had been patients in a university family practice setting for at least five years between 1980 and 1986 were surveyed by telephone. Questions were designed to determine factors considered important to obese individuals in their weight-loss efforts and to determine factors related to weight loss among obese individuals. Nearly all of the survey participants felt that they had a good knowledge of nutrition and that they applied their knowledge of nutrition to their daily eating. They did not feel that additional knowledge of nutrition would help them control their obesity. Participants reporting physician attention to their obesity and recent weight-loss program experience were more likely to be categorized as weight losers over the five-year interval. Factors felt to be important in their weight loss by most patients who lost weight at some time were exercise and self-motivation.

Body Weight↗
PubMed1987

Psychotherapy by family physicians.

Practical, brief, specific techniques that primary care physicians can use in office counseling are reviewed. Useful applications of supportive therapy, cognitive therapy, and interpersonal therapy are described. Family therapy is introduced as a means of approaching problems originating in the social context.

Adaptation, Psychological↗
PubMed1986

Neonatal cortisol response to circumcision with anesthesia.

Eleven male newborns were circumcised with a local dorsal penile nerve block, and 13 controls were circumcised without anesthetic. Matched pairs of pre- and postcircumcision cortisol levels in the two groups were compared. The adrenal cortisol response to surgery was not significantly reduced by the administration of lidocaine. Blood sampling and anesthetic injection of venipuncture alone did not evoke the adrenal response in uncircumcised control infants. Cortical input or secondary epinephrine elevation may be producing the cortisol elevation in infants despite regional blockage of the afferent nerve pathways.

Adrenal Glands↗
PubMed1985

Electrodermal potential and conductance measurements clinically discriminate between cystic fibrosis and control patients.

To evaluate the adaptation of electrodermal techniques for cystic fibrosis screening, skin surface bioelectric measurements were recorded from 37 established cystic fibrosis patients, 45 asthmatic patients, and 10 normal controls, ranging in age from 6 to 22 yr. Six skin potential and six skin conductance measures of sweat gland activity without the collection of sweat distinguished between the cystic fibrosis, normal, and asthmatic groups (F ratios greater than 10.0; p less than 0.0001). Discriminant analysis using the two best electrodermal measures (the mean of five preresponse potential levels and the mean of five preresponse conductance levels for each subject) to assign experimental group membership matched actual group membership with 92.7% accuracy. We believe these results warrant further investigation of electrodermal procedures as a direct, simple, yet noninvasive means of screening for cystic fibrosis.

Adolescent↗
PubMed1984

Factors associated with behavior change in family physicians after CME presentation.

Registrants of a four-day family practice refresher course responded to a survey assessing their reaction to a brief presentation recommending the use of penile anesthesia in newborn circumcision. Of the 110 respondents who had attended that session, 56 percent reacted favorably to the recommendation, 27 percent rejected it, and 17 percent had mixed reactions. Twenty-three percent of the respondents who were performing circumcisions at the time of the survey said they began using the recommended procedure following the conference, most with good results. Those who did not adopt the recommendation said using penile anesthesia for newborn circumcision was unnecessary, potentially dangerous, or both. The results suggest that evaluation of behavior change resulting from continuing medical education efforts should consider attitudinal variables on the part of those attending conferences in addition to variables related to the overall quality of the conference.

Anesthesia, Local↗
PubMed1983

Physiologic stress reduction by a local anesthetic during newborn circumcision.

To evaluate the effectiveness of the dorsal penile nerve block in reducing the stress of circumcision upon newborns, physiologic measurements in 30 healthy full-term infants (including transcutaneous oxygen levels, crying time, heart rate, and respiratory rate) were monitored continuously before, during, and after the operation. Infants receiving the dorsal penile nerve block with lidocaine (1% Xylocaine) (N = 20) experienced significantly less stress, as evidenced by smaller decreases in transcutaneous oxygen pressure levels, less time spent crying, and smaller increases in heart rate, than infants circumcised in an identical manner without anesthetic (N = 10). No complications resulted from injection of the local anesthetic or from the circumcision procedure itself. Inasmuch as dorsal penile nerve block has a low complication rate, is simple to learn, and adds little time or expense to the overall procedure, and if it proves to be as effective clinically as the physiologic data indicate, the dorsal penile nerve block should be considered for every infant undergoing circumcision.

Anesthesia, Local↗