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PubMed1991

Idiopathic gastroparesis is associated with a multiplicity of severe dietary deficiencies.

UNLABELLED: Idiopathic gastroparesis (IG), a disorder characterized by abnormally delayed emptying of food from the stomach, is associated with many symptoms that could have an impact on dietary intake. The intake of dietary protein, carbohydrate, fat, fiber, vitamins, and minerals was prospectively evaluated in patients with symptomatic IG and compared with asymptomatic controls. Twenty-four patients and 24 age- and sex-matched controls completed a detailed 7-day diet record while consuming a self-selected diet. Dietary information was entered into a computer and analyzed using the Nutranal program. Results were expressed as daily intake and percent recommended dietary allowance (%RDA) when applicable. Patients consumed a diet containing fewer calories than would have been predicted based on age, height, sex, frame, and weight (85% of calculated energy expenditure vs 100%) for controls. Although patients with IG consumed significantly fewer calories than controls (1112 kcal vs 1431 kcal), the proportion of fat (32% vs 34%), carbohydrate (49% vs 48%), and protein (17% vs 16%) was similar in the two groups. Intake of vitamins B6, vitamin C, folate, niacin, riboflavin, thiamine, calcium, copper, iron, magnesium, phosphorus, and zinc were below the %RDA. Intake of vitamin B12, vitamin C, folate, thiamine, niacin, magnesium, phosphorus, and zinc were significantly less than controls. Vitamin A intake was above the RDA and not different from that of controls. Prolonged t1/2 of solids correlated with diminished intake of protein, iron, niacin, and potassium. They correlated inversely with serum albumin in patients with idiopathic gastroparesis. CONCLUSION: Although eating less, patients with IG do not consistently alter the proportion of fat, carbohydrate, and protein in their diets. Because their diet is markedly deficient in a number of essential vitamins and minerals, dietary evaluation and counseling is suggested for all patients with idiopathic gastroparesis.

Adult↗

PubMed1991

Relationships of anxiety scores to screening and training status of air traffic controllers.

The present study assessed the relationship between anxiety, as measured by the State-Trait Personality Inventory (STPI), and success of post-strike air traffic control specialist (ATCS) trainees at the FAA Academy and during field training. The STPI was administered to students who entered the FAA Academy between June 1984 and September 1985. Academy test scores were obtained for 1,790 students in the en route option. Criterion data included the field training status of the Academy graduates as of July 1988. Statistical analyses determined the relationships between ATCS student scores on the STPI measures and a) normative data and b) Academy screening and field training results. ATCS students reported significantly lower state (current level) and trait (proneness) levels of anxiety than did either college students or military recruits. Trainees who had relatively high scores (for ATCSs) on a combined index of the trait and state measures of anxiety exhibited significantly higher a) percentages of Academy failures/withdrawals, b) percentages of option switches in the field, and c) overall field attrition, than did trainees with low scores. Results support the operation of some personality-related self-selection among ATCS applicants regarding anxiety and the importance of this low anxiety characteristic for ATCS job success.

Aerospace Medicine↗

PubMed1991

Segmental contributions to total body momentum in sit-to-stand.

In a previous investigation, we reported that the maximum linear momentum of the body center of mass (CM) during a sit-to-stand task showed a relative invariance in the horizontal vs the vertical direction of motion as the speed of ascent increased from natural to fast. The present study investigated the segmental origin of this directionally specific difference by examining the linear momentum of the shank, thigh, and head-arm-trunk segments for ten healthy young adults at slow, natural, and fast self-selected speeds. Findings indicated that the head-arm-trunk was the major contributor to the horizontal maximum linear momentum of the CM and accounted for the relative invariance in its magnitude. In contrast, the thigh was the major contributor to the vertical maximum linear momentum of the CM and was responsible for the progressive increase in its magnitude across the range of speeds. Moreover, the compatibility between the motions of the head-arm-trunk and of the shank in their general profile and peak magnitudes further suggested that a simplifying strategy may have been employed to reduce the overall number of degrees of freedom associated with the sit-to-stand movement.

Adult↗

PubMed1990

An assessment of the level of dental and mouthcare knowledge amongst nurses working with elderly patients.

A 60 item questionnaire was completed by a self-selected sample of nurses working with elderly patients. The questionnaire was divided into three sections; to collect personal data, to assess the nurses' attitude to mouthcare and their level of training in this subject, and to assess the level of dental knowledge. This paper identifies the disadvantages of using a self selected as opposed to a random sample. Analysis of the completed questionnaires revealed a fairly high level of basic training in dental and mouthcare matters. There was however, a paucity of specific dental knowledge e.g. there was some confusion over the aetiology and prevention of dental caries and also as to the difference between gingivitis and periodontitis. In addition, few nurses seemed to be aware of the effects systemic disease and drugs may have on the oral tissues. In spite of this most respondents achieved more than 50 per cent correct answers. A number of recommendations to improve nurses' dental knowledge is given at the end of the article.

Aged↗

PubMedDate not supplied

Determining HIV seroprevalence among women in women's health clinics.

Human immunodeficiency virus, type 1 (HIV), seroprevalence studies are needed to determine the level and trends of HIV infection among women attending family planning, abortion, and prenatal care clinics in the United States. A review of published and unpublished studies showed that HIV seroprevalence among women attending women's health clinics was 0 to 2.6 percent, although the studies were difficult to compare because of differences in methodology. The Centers for Disease Control, in association with State and local health departments, has developed a standardized protocol to determine HIV seroprevalence among women attending women's health clinics in selected metropolitan areas. Blinded HIV serosurveys (serologic test results not identified with a person) are being conducted annually in selected sentinel clinics in order to obtain estimates of HIV seroprevalence unbiased by self-selection, as well as to monitor trends in infection among clients attending these clinics. In areas with high HIV seroprevalence, nonblinded serosurveys (in which clients voluntarily agree to participate) will be used to assess behaviors that may place women at increased risk of exposure to HIV. Data from the surveys can be used in developing age-specific and culturally appropriate AIDS educational materials, assessing the amount and type of counseling activities required, and evaluating acquired immunodeficiency syndrome (AIDS) prevention activities. The information will provide epidemiologic data to complement the results of other surveys in characterizing the scope of HIV infection among women of childbearing age in the United States.

AIDS Serodiagnosis↗

PubMedDate not supplied

Using seroprevalence data in managing public health programs.

An objective of the Centers for Disease Control (CDC) family of HIV seroprevalence surveys, conducted by State and local health departments, is the collection of seroprevalence data that may be useful in managing public health programs. In prevention programs, seroprevalence data may be used in allocating resources, in determining the types and amount of education, counseling, and testing services offered, and in identifying access points for HIV-infected persons for medical followup and care. Over time, data will be useful in detecting and following trends in HIV infection and in evaluating the impact of program activities to prevent HIV infection. No single seroprevalence survey is representative of the entire population of a metropolitan area. Each type of survey has strengths and limitations that must be considered when interpreting seroprevalence data. However, results from the family of surveys are the best available data because they are relatively unaffected by self-selection bias, they are standardized, and the information is collected over time. Characterization of the population surveyed and adherence to standard CDC protocols improve the quality of the data. Consultants in health departments and at CDC form a network for providing technical support and disseminating data to health care providers and program managers.

AIDS Serodiagnosis↗

PubMed1990

Intake of essential and toxic trace elements in a random sample of Danish men as determined by the duplicate portion sampling technique.

Average daily intakes of essential and toxic trace elements from self-selected diets consumed by 100 men, selected as a random sample among the population of 30-34 year-old men in one urban and two rural areas of Denmark, were determined by the analysis of 48 h duplicate food portions. Median daily dietary intakes were 11.3 mg for zinc, 1.1 mg for copper, 11.3 mg for iron, 51 micrograms for selenium, 3.9 mg for manganese, 99 micrograms for molybdenum, 7 micrograms for lead and 11 micrograms for cadmium. Median dietary intake of mercury was below the detection limit. The observed nitrogen, sodium and potassium intakes were about 25% lower than the average total daily excretion of these constituents. It is therefore assumed that dietary intakes of nutrients during the duplicate portion sampling period were reduced by about 25% and that the observed intakes of trace elements can be regarded as minimum estimates of habitual intake. Taking this into consideration, it is concluded that the content of essential trace elements in Danish diets seems to be adequate and the amounts of the elements lead, mercury and cadmium are of little concern as regards health aspects.

Adult↗

PubMed1978

Update of naltrexone treatment.

To summarize, then, our work with naltrexone in a multi-modality treatment program indicates that it appeals to about 5-10 percent of narcotic addicts--those who conciously want to obtain drug-free status. It does significantly attentuate the effect of narcotics to the extent that they lose their reinforcing properties, and it has minimal side effects. Although we treated a self-selected population, it is noteworthy that about 10 percent of those who remained on naltrexone for more than a week were still opiate free 6 months after cessation of treatment. For some it appeared to be a turning point in their lives. It was the first time in years that they could live in their neighborhood and not be either intoxicated or occupied with the pursuit of narcotics. Our behavioral studies have identified a number of conditioned psychophysiological responses associated with the self-injection ritual. So far, although we have succeeded in extinguishing some of these responses, this has not resulted in an improved clinical outcome. We are currently working on more comprehensive behavioral treatments, but the clinical significance of these conditioned responses is uncertain at present.

Adult↗

PubMed1990

Sensitivity of the appetite control system in obese subjects to nutritional and serotoninergic challenges.

The sensitivity of the appetite system of a group of obese individuals was assessed in response to two challenges known to reduce hunger and enhance satiety in lean people. The challenges were the presentation of a caloric (high protein) load and the activation of serotonin systems. Eight obese female adults (BMI = 38) received 2 X 15 mg d-fenfluramine or placebo daily for 3 days, the study conforming to a 2 X 2 factor (drug X lunch type), double blind, repeated measures design. Three hours after dosing on day 3 they ate either a high carbohydrate (63 percent of total energy) or high protein (54 percent) lunchtime meal (the caloric load). These fixed meal challenges were equal in energy (475 kcal), weight and fat content. Ratings of hunger motivation and food preferences were tracked over the course of lunch and for a further 3 hours, at which point subjects returned for a self-selection test meal. Intakes from this second open meal revealed significant main effects of both caloric load and drug on energy intake, with the high protein d-fenfluramine combination being the most potent anorectic pairing. These findings were supported by the profiles of hunger motivation. This study has confirmed that the appetite system of these subjects was responsive to these biologically relevant challenges. The results suggest that the combination of an appetite modulating drug with specific dietary intervention may represent an effective strategy for the management of hunger arising from caloric restriction.

Adult↗

PubMed1990

Prevalence of anisometropia in volunteer laboratory and school screening populations.

For 10 years our laboratory has conducted, a longitudinal study of focusing and motor behavior of a volunteer population of 686 subjects aged 3 months to 9 years. Its purpose is to characterize normal refractive development in infants and children and to relate refractive anomalies to subsequent visual problems. Using age-related criteria for anisometropia adjusted to detect the most unusual 5% of the refractions on a test battery, we have found 19 nonstrabismic, anisometropic subjects (2.8% of total subject population). Of these, eight were either seen once or their anisometropia appeared at their last visit. Of the remaining 11 subjects, all had a reduction of their anisometropia to within normal limits on subsequent visits. Thus our current best estimate of persistent infant anisometropia is 0%, a startling result. By comparison, we found ten strabismic subjects (1.46%), two of whom had persistent anisometropia. Although we did not believe that anisometropic subjects could self-select and not participate in the study, it was possible that the volunteer laboratory population had characteristics atypical of the county at large. Thus we conducted a screening of 374 Head Start and first-grade pupils throughout the county, using the same methods. We found virtually no difference in the average refractive conditions between the laboratory and school populations and no significant difference in the prevalence of visual disorders. The very low prevalence of anisometropia in infants and young children in both populations has important implications for the etiology of anisometropic amblyopia.

Anisometropia↗

PubMed1990

Natural childbirth--the Johannesburg Hospital experience, 1983-1989.

The Johannesburg Hospital Active Birth Unit (ABU), the only one of its kind in southern Africa to date, has provided an alternative to conventional labour practices since 1983. In a retrospective study of the results achieved in this unit the intrapartum records of 492 patients admitted to the ABU between 1 March 1983 and 30 June 1989 were analysed. During the 6.3-year study period 364 patients (74%) successfully laboured and delivered within the unit. These figures included 50 underwater deliveries. One hundred and twenty-eight patients required intrapartum transfer to the conventional labour ward and of these 44 achieved spontaneous vaginal delivery. Thirty-four patients (7%) 'self-selecting' for natural childbirth ultimately required caesarean section delivery. Primiparous patients were more likely than their multiparous counterparts to require intrapartum transfer to the labour ward (38% v. 13%). Birth outcome results achieved in the Johannesburg Hospital ABU compare favourably with those for 6 other ABUs reported in the literature.

Female↗

PubMed1990

Occupational stress and well-being: do seafarers harbor more health problems than people on the shore?

The popular image of life at sea is one of stress: often difficult physical conditions, dislocation, isolation and less than ideal personal habits. In order to determine whether this stressful way of life is manifested when seamen's health status is assessed by standard measurements, we studied 144 sea captains and marine chief engineers as compared with a group of ordinarily employed men. The referent men were matched for age, ethnic origin, and level of education with the seamen. Outcome measures included a wide spectrum of physiological, psychological and behavioral indices. The comparisons revealed only mild differences between the two groups. Captains and chief engineers tend to harbor slightly higher levels of certain biochemical or physiological parameters (risk factors), such as serum cholesterol and uric acid, hemoglobin level and leukocyte count. Certain behavioral risk factors were more dominant among the seamen than among the control group (smoking level, alcohol consumption and lack of leisure-time physical activity). The study group did not exhibit a greater prevalence of overt disease or a higher degree of psychological symptoms. It is suggested that the group under study represents a self-selected group of persons well adjusted to their job and their special way of life.

Adult↗

PubMed1990

Physiologic and perceptual responses during treadmill running with ankle weights.

This study examined the effects of ankle weighting on physiologic and perceptual responses during treadmill running in seven healthy, female recreational runners with a mean maximal aerobic power of 48.4 +/- 4.0 ml/kg/min. Each subject completed four experimental one-mile runs at individually selected treadmill running speeds with 0, 1.6, 3.2 and 4.8 kg weights on their ankles. The subjects selected a speed at which they would run (train) if their objectives were to significantly improve cardiovascular function and induce weight loss. Metabolic and cardiovascular responses were continuously monitored, and ratings of perceived exertion were recorded near the end of the activity. During the unweighted run, the subjects selected a running speed of 6.87 +/- 0.63 mph which resulted in a net energy expenditure of 0.153 kcal/kg/min or 1.34 +/- 0.16 kcal/kg/mile. This corresponded to a training intensity of 76.3% +/- 5.1% of maximum oxygen consumption or 88.1% +/- 9.7% of maximum heart rate. Addition of weight to the ankles caused a significant decrease (p less than .05) in the running speed selected and, therefore, did not result in any significant changes (p greater than .05) in the rate of oxygen consumption, heart rate or ratings of perceived exertion when compared to the unweighted condition. These observations are in contrast to previous studies on ankle weighting which were conducted at fixed treadmill running speeds. However, the use of ankle weights did have a tendency to increase gross and net energy expenditure of running when values were expressed in kcal/mile because of slower self-selected running speeds under these conditions. This increase in energy expenditure could be of physiologic significance if running with ankle weights was performed on a regular basis at a fixed distance.

Adult↗

PubMed1990

dl-fenfluramine challenge to nutrient-specific textural preference conditioned by concurrent presentation of two diets.

Effects of the ingestion of protein and carbohydrate conditioned a preference for one size of chow particle over another, which was triggered by need for a specific nutrient. This learned elicitation of nutrient-specific dietary selection was not changed by injection of dl-fenfluramine HCl (2.5 mg/kg). This indicates that previously observed effects of fenfluramine on differential intakes of dextrin- and casein-rich diets do not depend on nutrient-specific self-selection.

Animals↗

PubMed1979

Potential effect of demographic and other variables in studies comparing morbidity of breast-fed and bottle-fed infants.

Comparing the morbidity of breast-fed and bottle-fed infants is confounded by inherent differences in breast-feeding and bottle-feeding mothers and their infants. Self-selection introduces complex variables encompassing much more than milk source used for infant feeding. Reasons for selecting breast or bottle feeding relate to demographic, socioeconomic, educational, ethnic, cultural, and psychological factors, as well as maternal and infant physical and emotional health. Many of the differences in the maternal populations may affect infant care practices, access to medical care, and infant health status. Studies published to date have not quantified these confounding effects and other potential biases in comparing morbidity to breast- and bottle-fed infants and the relationship between milk source and incidence of infantile disease remains in question. There is need for more cautious use of the available data and investigators must seek ways to design future studies to take into account the differences between breast-feeding and bottle-feeding mothers that affect both reported and actual infant morbidity.

Bottle Feeding↗

PubMedDate not supplied

[Treatment of the sick elderly in households accommodating several generations].

Multigenerational households with widowed persons aged 70 and more have been studied in order to determine the relationship between the following two groups of variables: (a) variables in the aged person describing the existence and degree of an organic mental impairment due to a dementive process and of other signs of physical illnesses. (b) variables in her daughter or daughter in law consisting of selfratings of psychosomatic complaints and of attitude-scales. Results were as follows: (a) If there were indications of personality changes due to an organic brain syndrom the relatives had a lower degree of life-satisfaction and more frequently suffered from psychosomatic symptoms and interpersonal stress than those, whose old relatives showed an unaltered personality. (b) A great number of comparisons failed to show any statistical differences. Especially severe physical illness, organic brain syndrome and the need for physical care were not related to life satisfaction, psychosomatic complaints, stress due to emotional involvement and the attitude towards home-care. Our attempt to explain the missing correlations led to the following factors: the small size of the sample, self-selection of the sample and possibly inappropriate operationalisation and measurement of variables. In respect to these results the ongoing study will be modified in some details: There will be a qualitative analysis of transcribed semi-structured interviews. The proportion of families with severely demented relatives will be increased. In an additional step we shall examine families, who have decided to transfer their old member into an institution.

Aged↗

PubMed1978

The effect of energy and nitrogen intake upon urea production in children with uremia and undernutrition.

Children with severe uremia who had anorexia were observed in a clinical study center where dietary energy and nitrogen intake could be compared with urea nitrogen production (UNPr). The children received a supplement of dextrose and amino acids at night, ate a self-selected diet and were encouraged to use carbohydrate supplements. Energy intake varied from 22 to 110 kcal/kg/day and nitrogen intake from 105 to 323 mg/kg/day. UNPr was reciprocally related to energy intake. Nitrogen intake minus UNPr, an index of nitrogen balance, was positively related to energy intake. UNPr was not related to nitrogen intake. Nitrogen intake (NI) and NI-UNPr were correlated and the slope of the regression was 1.15. We inferred from the data that low energy intakes (less than 60 kcal/kg/day) were associated with catabolic losses of body protein. Intakes above that level were associated with a low and stable rate of UNPr. The level of energy and nitrogen intake within the range observed limited the rate of nitrogen retention. Once maintenance requirements for energy and nitrogen were satisfied, the efficiency with which nitrogen was used for net protein synthesis was very high.

Adolescent↗

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↗