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PubMed1981

The Columbia population study. III. Volunteer status, educational background, and plasma total cholesterol level in a prepaid health care program.

From 1972 through 1975 a study of plasma lipid levels was conducted at the Columbia Medical Plan (a prepaid group practice in an upper-middle-class suburban community) in accordance with nationally standardized interview, blood-drawing and laboratory procedures of the Lipid Research Clinics Program. Data were obtained from a large group of volunteers from the plan as well as from subjects selected by random sampling from membership rolls. Of 2,591 fasting, nonpregnant adults (age greater than or equal to 20 years), 825 were volunteers and 1,766 were randomly selected subjects. Analysis of the plasma total cholesterol values indicated a possible association of volunteer status and higher educational levels with a lower plasma total cholesterol level. Age- and sex-specific comparisons confirmed this finding, although the magnitude of the differences was quite small from the standpoint of clinical risk. The data suggest that even within educational strata, self-selection for cholesterol screening was associated with a lower cholesterol level.

Adult↗

PubMedDate not supplied

Commitment to Underserved People (C.U.P.) program at the University of Arizona.

The C.U.P. (Commitment to Underserved People) Program was established at the University of Arizona College of Medicine to reinforce the commitment of a self-selected group of medical students to careers with medically underserved people and to help them acquire some of the special knowledge, skills, and attitudes essential to effective performance in such careers. The program brings together some preexisting curricular offerings and a number of additional extracurricular activities and experiences. The time demands on the participating students are significant, but not excessive. Support activities are an important aspect and include periodic group meetings, an annual retreat, faculty role models as students advisors, and personal counseling when needed. The program is coordinated by the Department of Family and Community Medicine, but relies on participation of faculty from other primary care departments and the cooperation of a number of community agencies and clinics. The C.U.P. Program was developed in response to an expressed student need, and students have continued to play an essential role in its design and direction.

Arizona↗

PubMed1980

Turbidimetry of inorganic sulfate, ester sulfate, and total sulfur in urine.

We describe simple and precise methods for the determination of inorganic sulfate, ester sulfate, and total sulfur in urine. The methods are based on turbidimetry of sulfate as barium sulfate in the presence of a small amount of preformed barium sulfate and with polyethylene glycol as a stabilizing agent. Inorganic sulfate is directly determined, whereas ester sulfate is measured after removal of inorganic sulfate, followed by acid hydrolysis. Total sulfur is determined after wet oxidation of the sample with nitric acid and perchloric acid in the presence of vanadate as a catalyst. We also report excretion values for healthy persons on a self-selected diet. Men excrete significantly higher amounts of inorganic sulfate and total sulfur than women, but this sex-related difference becomes insignificant if excretion values are expressed relative to creatinine.

Chromatography, Ion Exchange↗

PubMed1980

Walking efficiency before and after total hip replacement as determined by oxygen consumption.

Seventy-seven patients receiving either unilateral or bilateral total hip replacement were studied before and for as long as four years after operation. Their walking velocity and efficiency (the latter determined by measuring oxygen consumption) improved after operation. Total hip replacement allowed relatively equal postoperative efficiency and velocity for patients with unilateral and bilateral disease. While no consistent relationships were found between the components of the Iowa hip-rating scale, significant correlations were found between the composite Iowa hip-rating score and oxygen consumption. Data indicate that measurement of self-selected velocity in patients with hip disease is a satisfactory indicator of walking efficiency.

Aged↗

PubMed1980

Timing of REM sleep is coupled to the circadian rhythm of body temperature in man.

Ten male subjects were studied for a total of 306 days on self-selected schedules. Four of them developed bedrest-activity cycle period lengths very different from 24 hr (mean = 36.8 hr) despite the persistence of near-24-hr oscillations in other physiologic functions, including that of body temperature (mean = 24.6 hr). The percentage of sleep time spent in REM sleep varied significantly with the phase of that near-24-hr body temperature cycle. The peak in REM sleep propensity (RSP) occurred on the rising slope of the average body temperature curve, coincident with the phase of peak sleep tendency. This was associated with a significantly increased REM episode duration and shortened REM latency (including sleep-onset REM episodes), but without a significant change in the REM-NREM cycle length. We conclude that there is an endogenous circadian rhythm of REM sleep propensity which is closely coupled to the body temperature rhythm and is capable of free-running with a period different from both 24 hr and the average period of the sleep-wake cycle.

Adult↗

PubMed1980

Utility of serum ferritin as a measure of iron deficiency in normal males undergoing repetitive phlebotomy.

Hematologic indices and iron balance data were obtained on 22 normal male volunteers who were subjected to a mean +/- SD phlebotomy of 164 +/- 34 ml whole blood/mo while living in a controlled environment. Over an average stay of 5 mo, volunteers did not develop anemia, but did display a reduction in iron stores that was quantitated by measurement of serum ferritin and iron balance. The percent saturation of transferrin and the usual erythrocyte parameters did not reflect changes in iron status. Loss of iron, which was calculated from quantitative phlebotomy and iron balance data, showed that a decrease of 1 ng of serum ferritin represented a loss of 4.5 +/- 5.3 mg of iron in 10 men whose initial serum ferritins were greater than 25 ng/ml, and 25.3 +/- 58.8 mg of iron in 7 men whose initial serum ferritins were less than 25 ng/ml. The period required for 3 volunteers who consumed a self-selected mixed diet at home to replace their depleted iron stores to prephlebotomy levels was about 4.5 mo. The sensitivity of serum ferritin as an index of iron stores was affirmed. In addition it was found that normal men who were consuming a mixed diet containing about 15 mg of iron daily and losing blood at a rate of 164 +/- 34 ml/mo did not increase their iron absorption sufficiently to compensate for the iron loss.

Adult↗

PubMed1981

Consuming capacity for single meals in humans after a 24-hour fast.

Self-selected, ad libitum meals were repeatedly fed to 5 healthy male subjects in order to empirically assess the influence of various intravenous and intraduodenally delivered solutions on food consumption. The solutions included i.v. and i.d. saline, i.v. and i.d. glucose, and i.v. autologous plasma feedings which had been previously obtained from the subjects after feeding or fasting states. Each subject had 11 meals under the various conditions. Liquid and solid food intakes in grams and calories were measured with each meal. No significant mean differences in food consumption were detected between the various i.v. and i.d. conditions; hence, food consumption for all meals was combined for the 5 subjects. Significant individual differences in food intakes were found that could not be correlated with body size, gastric emptying rates, or with the capacity to secrete gastric acid.

Adult↗

PubMed1980

[Modifications in the feeding behavior of the rat, induced by antimitotic drugs: effects of hydroxyurea].

The effects of Hydroxyurea treatment on food intake and on the self-selection between a protein free diet and a complete one are different from those observed during Cyclophosphamide and Mustine Hydrochloride treatment and appear to be similar to those observed during Methotrexate treatment; these may be referred exclusively to a toxic action of the drug on the liver and on the mucous membranes of digestive apparatus. The urea, a product of Hydroxyurea metabolism, does not seem to induce modifications on food intake both as to the quantitative and qualitative aspect.

Animals↗

PubMed1979

Gastric secretory and humoral responses to anticipated feeding in five men.

It is believed that humans anticipate appetizing meals by increasing vagally mediated gastric acid secretion. Studies were conducted on 5 normal male volunteers to characterize further the secretory response to anticipated meals. Plasma gastrin and glucose levels were monitored to assess the possibility that these humoral factors participated in the observed secretory changes. Subjects were not fed for 22 hr and were intubated at 10 AM. Basal gastric collections were begun, and at 1 PM on different days, subjects either (a) selected meals of choice prepared in their presence for 1 hr before nasogastric tube withdrawal and meal ingestion or (b) were not food-teased or fed. Gastric collections were obtained every 10 min during the "test" hour (1-2 PM) during both (a) and (b) studies and titrated for gastric acid. Blood samples for plasma glucose and RIA gastrin were obtained during basal and test hours every 10 min. Pentagastrin-stimulated maximal acid output studies were conducted on all subjects on separate days. Results showed a progressive and statistically significant rise in gastric acid secretion when an appetizing, self-selected meal was anticipated. The magnitude of this rise was 55% of the mean pentagastrin-induced acid response. This acid response did not correlate with changes in plasma glucose or gastrin. The study demonstrated that pure psychic stimulation may be as effective an acid stimulant as sham feeding.

Adult↗

PubMed1995

Functional encopresis: symptom reduction and behavioral improvement.

This study assessed the relationship between functional encopresis and accompanying problems: emotional, behavioral, and social. Symptom resolution and changes in these concomitant problems were studied. Seventy-six children, 6 to 12 years of age, enrolled in this "self-selected," nonequivalent, control (contrast) group research design with 38 children in each group. Using the Child Behavior Checklist, children were tested before treatment and 6 months later. The results showed that children with encopresis had significantly more emotional/behavioral problems and poorer social competence before treatment than children in the contrast group; combined medical and psychotherapeutic intervention led to a significant reduction in soiling frequency, and children with encopresis experienced significantly fewer behavioral problems and significantly improved social competence after treatment. There was a small group of children for whom treatment was difficult. The data suggest that highly elevated behavior problem scores, especially in association with parental negativeness, may be related to poor treatment outcome.

Behavior Therapy↗

PubMedDate not supplied

Needs of hospice and clinic patients with cancer.

The purposes of this descriptive study were: (1) to compare the self-selected needs of 69 patients with cancer, 31 from a nonprofit hospice, and 38 from a university cancer center located in the mid-south; and (2) to establish the reliability of the Cancer Patient Need Survey for hospice patients. Patients completed the Cancer Patient Need Survey and a demographic data form. Hospice and clinic patients rated the category of coping needs most important. Clinic patients also ranked the category of information needs as a priority, but did not find these needs as well met. Both groups ranked as their top individual needs support from family and friends, and a patient caregiver. Reliabilities of the instrument for the groups range from 0.91 to 0.93. The Cancer Patient Need Survey is a useful instrument for assessing and testing the needs of clinic patients, but additional work needs to be done in modifying the instrument for use with hospice patients.

Adult↗

PubMed1995

A double-blind crossover trial of clomipramine for rapid ejaculation in 15 couples.

BACKGROUND: The purpose of this study was to assess the sexual and psychosocial efficacy of clomipramine for rapid ejaculation. METHODS: Fifteen physically healthy, self-selected couples (men had a mean age of 38 years) who met six eligibility criteria and did not meet five exclusion criteria participated in a variable-length, repeated measures, randomized, double-blind, placebo-controlled crossover study with a 2-month follow-up period. Sexual and psychosocial assessments were conducted at baseline, after placebo, after 25 mg/day of clomipramine, after 50 mg/day of clomipramine, and at the 2-month follow-up point. The major outcome measures included stopwatch timing of ejaculation latencies, modified Case Western Reserve University Sexual Function Questionnaire, Symptom Checklist-90-R, Dyadic Adjustment Scale, State-Trait Anxiety Inventory, and the Harder Self-Esteem Inventory. RESULTS: Baseline mean ejaculatory latency was 81 seconds; 25 mg/day of clomipramine increased it to 202 seconds and 50 mg/day of clomipramine to 419 seconds. This resulted in significantly greater sexual satisfaction scores for men and their partners (men, p < .001; women, p < .05), improvements in partner coital orgasmic attainment, and greater relationship and emotional satisfaction for the men. Withdrawal of the drug caused ejaculatory latencies to return to baseline. CONCLUSION: Clomipramine appears to be effective in significantly lengthening ejaculatory latencies and increasing sexual and relationship satisfaction. It can be a cost-effective chronic therapy for selected patients. These impressive results should not be expected in a less carefully screened population of men concerned about the timing of their orgasm during intercourse.

Adult↗

PubMed1995

The presbyopic add. I. Magnitude and distribution in a historical context.

The presbyopic addition or 'add' is the (binocular) spherical positive power supplement superimposed on any distance refractive correction to counter near vision difficulties associated with the physiological age-related loss of accommodation and consequent recession of the near point: its necessity is first encountered in middle age. The continuous (linear) ascending trend in near lens power versus increasing age advocated since the seventeenth century is at odds with the twentieth-century clinical observation that there is a deceleration in add requirement beyond an individual's mid-fifties. It is shown here that this difference is reconciled--in broadly qualitative terms if not in magnitude-when typical clinical near addition data are superimposed on the accepted distance hypermetropic refractive base recorded from early middle age onwards: a continuous rising function is produced spanning most of the three decades beyond 40 years of age. This result is considered in the context of the age markings found on certain eighteenth-century antique near vision glasses and the recommendations attached to the self-selection of ready-made reading glasses in the late twentieth century.

Adult↗

PubMed1995

Cardiorespiratory responses during exercise in competitive in-line skaters.

This study describes the cardiorespiratory responses of 12 male (age = 30 +/- 6 yr) competitive in-line skaters during peak and submaximal skating. We hypothesized that velocities of 22.5 and 27.4 km.h-1 would elicit heart rate (HR) and oxygen consumption (VO2) responses consistent with the American College of Sports Medicine's guidelines for developing cardiorespiratory fitness. Using a 644-m indoor cement course, subjects completed 10 trials comprised of various velocities, stroke frequencies, and body positions. At 22.5 km.h-1, HR and VO2 were 74 and 51% of peak, respectively. At 27.4 km.hr-1, HR and VO2 were 85 and 72% of peak, respectively. When compared to the College's guidelines, regression analysis revealed a leftward shift in the VO2-HR relationship, evidenced by a disproportionately higher HR at a VO2 approximating 60 vs 80% of peak. At 22.5 km.h-1 our skaters self-selected a stroke frequency which resulted in less of an increase in both HR and VO2, when compared to the imposed stroke frequencies of 50 min-1 and 70 min-1. Also, skating at 27.4 km.h-1 in the bent vs upright position resulted in less of an increase in HR and VO2. Competitive in-line skaters are capable of safely skating at velocities sufficient to stimulate an increase in cardiorespiratory fitness. These athletes select a stroke frequency and utilize a body position which results in favorable HR and VO2 responses.

Adult↗

PubMed1994

[Effects of natural mood changes on discrimination performance and response trends in pattern recognition].

The effects of mood on thinking and behavior are characterized by "loosening" in the case of positive feeling states and "tightening" for negative ones (Fiedler, 1988). Style of cognitive processing, effort expenditure, and capacity models are discussed as explanatory concepts. To compare these approaches, the theory of signal detection provides methods for the independent evaluation of parameters of response bias and discrimination (and also efficiency). A laboratory experiment (Klauer et al., 1991) was replicated and supplemented by a field study. In the sense of convergent and discriminant validation of the insufficient techniques of mood induction, the naturally occurring mood changes of everyday life were used as mood manipulations. 13 subjects (M = 25.9 years of age, SD = 3.8) reported their feeling states on 18 days for self-selected episodes, which represented the range of their mood changes. Immediately after each mood report, they worked on a visual discrimination task. The indices of signal detection theory for response bias, discrimination, and efficiency were calculated in each cases, and correlated with measures of emotional and unspecific feeling states. Along with a shift from negative to positive feeling states, a trend towards a liberal response bias, a higher discrimination rate, and a greater efficiency resulted. Our findings replicate the laboratory experiment and support the effort expenditure and cognitive processing style view, rather than the reduced-capacity explanation. Speculations are offered concerning the emotional and cognitive processes which led to these results.

Adult↗

PubMed1995

Predictive testing for Huntington's disease: risk perception, reasons for testing and psychological profile of test applicants.

In the Center for Human Genetics in Leuven, predictive DNA-testing for Huntington's disease is available as a clinical service since November 1987, initially by DNA-linkage and since mid 1993 by direct mutation analysis. The multidisciplinary approach as well as the detailed test protocol are described. The present paper gives a sociodemographic description of the test applicants, their subjective evaluation of the risk and their motives for requesting the predictive test. Major attention is paid to the personality profile of the applicants who proceeded with testing. Psychometric testing revealed that this group of test applicants did not differ significantly from the general population for most characteristics and even had a number of more positive characteristics e.g. a higher ego-strength. The latter may reflect a self-selection of a more resourceful and emotionally healthier subgroup of at-risk persons. Nevertheless psychological evaluation also has identified a number of applicants with extremely high anxiety levels and other problems, who needed extra pretest and posttest counseling. The relatively high number of withdrawals from the test programme is another indication of the importance of adequate pretest counseling.

Adult↗

PubMed1995

Standardization of glycohemoglobin results and reference values in whole blood studied in 103 laboratories using 20 methods.

We investigated the effect of calibration with lyophilized calibrators on whole-blood glycohemoglobin (glyHb) results. One hundred three laboratories, using 20 different methods, determined glyHb in two lyophilized calibrators and two whole-blood samples. For whole-blood samples with low (5%) and high (9%) glyHb percentages, respectively, calibration decreased overall interlaboratory variation (CV) from 16% to 9% and from 11% to 6% and decreased intermethod variation from 14% to 6% and from 12% to 5%. Forty-seven laboratories, using 14 different methods, determined mean glyHb percentages in self-selected groups of 10 nondiabetic volunteers each. With calibration their overall mean (2SD) was 5.0% (0.5%), very close to the 5.0% (0.3%) derived from the reference method used in the Diabetes Control and Complications Trial. In both experiments the Abbott IMx and Vision showed deviating results. We conclude that, irrespective of the analytical method used, calibration enables standardization of glyHb results, reference values, and interpretation criteria.

Calibration↗

PubMed1994

Effect of carbohydrate ingestion on performance of non-fasted cyclists during a simulated 80-mile time trial.

The purpose of this study was to determine the effect of carbohydrate supplementation on finishing time of a realistically simulated 80 mile bicycle time trial. Fourteen trained cyclists pedalled at self-selected pace on their own bicycles on windload simulators. Two trials were performed one week apart. Each trial was preceded by two days of prescribed diet, with a final feeding 3-4 h prior to exercise. Following each 10 mile segment, subjects ingested either a non-caloric placebo (PL) or the carbohydrate maltodextrin supplement (MD; 5% maltodextrin +2% fructose) at dosage of 0.25 g.kg-1 body weight (mean intake rate, total: 37 g.h-1, 148 g) in a double blind, counter-balanced design. Mean (+/- SEM) finishing times were faster by 5% with MD (241.0 +/- 2.1 minutes versus 253.2 +/- 2.1 minutes), p < 0.05. With MD, serum glucose levels rose sharply after 40 miles and were significantly higher than PL (p < 0.05). Final glucose values were 6.0 +/- 0.2 mmol.l-1 and 4.1 +/- 0.2 mmol.l-1 for MD and PL, respectively. With MD, free fatty acid levels were significantly lower (p < 0.05), and riders sustained higher average intensity over the entire distance. At the finish, intensities were 64.7 +/- 1.9% VO2max and 55.3 +/- 1.9% VO2max for GP and PL, respectively. Mean carbohydrate oxidation was significantly higher (p < 0.05) for MD, 2.01 +/- 0.2 g.min-1 and 1.64 +/- 0.2 g.min-1 for MD and PL, respectively. These data show that ingestion of MD, during ultraendurance exercise, in comparison to PL, decreases the time to finish a self-paced bicycle time trial.

Adult↗