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PubMed2002

Genetic and environmental influences on the tracking of body size from birth to early adulthood.

OBJECTIVE: This study identified genetic and environmental influences on the tracking of body size from birth to 16 to 18.5 years of age. RESEARCH METHODS AND PROCEDURES: Longitudinal information was collected from a nationally representative sample of Finnish twin adolescents (birth cohorts 1975 to 1979) and their parents through questionnaires mailed when the twins were ages 16 and 18.5 years old. The sample included 702 monozygotic, 724 same-sex dizygotic, and 762 opposite-sex dizygotic sets of twins. The measures used were length, weight, ponderal index (kilograms per cubic meters), and gestational age at birth, and height, weight, and body mass index (kilograms per square meters) at 16 to 18.5 years of age. The changes in genetic and environmental influences on body size from birth to early adulthood were analyzed by quantitative genetic modeling. RESULTS: The twins who had a higher weight or ponderal index at birth were taller and heavier in early adulthood, whereas those who were longer at birth were taller, but not heavier, later in life. Adult height was affected more by the birth size than body mass index. In the genetic modeling analyses, the genetic factors accounting for the variation of body size became more apparent with age, and both genetic and environmental influences on stature had a sizable carry-over effect from birth to late adolescence, whereas for relative weight, the influences were more age-specific. DISCUSSION: The genetic and environmental architecture of body size changes from birth to adulthood. Even in monozygotic twins who share their genetic background, the initially larger twin tended to remain larger, demonstrating the long-lasting effects of fetal environment on final body size.

Adolescent↗
PubMed2003

Psychosocial distress associated with disfiguring eye conditions.

PURPOSE OF STUDY: Visible disfigurement is associated with a range of psychosocial difficulties; however, the problems encountered by patients with eye conditions are under-researched. This study aimed to establish the extent and type of psychosocial distress in this patient population, and to explore the extent to which patients' needs are currently met. METHOD: Standardised measures (anxiety, depression, appearance-related distress, and quality of life) and a semistructured interview (exploring individual experiences and satisfaction with care) were administered to 153 consecutive attenders at outpatient eye clinics in three different hospitals. Responses were analysed using descriptive statistics, multiple regression, and cluster analyses. RESULTS: Between 10 and 49% of the patient sample scored unfavourably on standardised measures in comparison with normative values. Cluster analyses revealed that more distressed patients typically exhibited higher levels of anxiety, depression, social anxiety, self-consciousness, and social avoidance. Quality of life scores were also less favourable. Distressed patients felt less well informed, less involved in their treatment, and less well supported in the clinic setting. Variability within the sample was high; however, the effects of the cause and duration of the condition were not significantly related to distress. Clinic staff identified a variety of constraints to meeting patients' need, including patient numbers, the lack of appropriate training, and the lack of referral possibilities. CONCLUSIONS: A considerable proportion of patients with disfiguring eye conditions experience high levels of psychosocial distress. Several options exist for ways in which patients' needs might more effectively be met within the constraints currently facing care providers.

Adaptation, Psychological↗
PubMed2000

Leptin serum concentrations predict the responsiveness of obese children and adolescents to weight excess reduction program.

BACKGROUND: A role for leptin to predict weight gain is still controversial. OBJECTIVE AND DESIGN: To determine the relationship between baseline serum leptin values and responsiveness to an educational-based weight excess reduction program (WERP), 418 (241 males and 185 females) obese subjects, aged 9-15 y, were recruited. WERP required 2 y of follow-up. Body mass index (BMI) was evaluated at baseline and at each semester of follow-up. The obese subjects were subdivided into responsives and non-responsives, according to reduction or not of their BMI Z-scores during the WERP. Leptin concentrations were assayed at baseline and were included together with other independent variables in statistical multiple regression analysis. RESULTS: At a preliminary multiple regression analysis, a significant positive correlation between leptin values and BMI Z-score reduction at the second, third and fourth semester of follow-up was registered. To determine the odds ratio of the subjects who were responsive or non-responsive at the various semesters of WERP follow-up, a stepwise logistic regression was used incorporating the same predictors, with the serum leptin values subdivided into quintiles and responsiveness and non-responsiveness as a binary outcome variable. The model offered a satisfying goodness of fit as shown by the sensitivity and specificity. The odds ratio of being responsive were significantly increased by greater quintiles of leptin serum concentrations. Furthermore, such odds ratios were much higher in pubertal than in prepubertal subjects. CONCLUSIONS: These findings support a significant role for serum leptin concentration in predicting BMI changes as a response to an educational excess weight reduction program.

Adolescent↗
PubMedDate not supplied

National Human Exposure Assessment Survey: analysis of exposure pathways and routes for arsenic and lead in EPA Region 5.

The National Human Exposure Assessment Survey (NHEXAS) Phase I field study conducted in EPA Region 5 (Great Lakes Area) provides extensive exposure data on a representative sample of approximately 250 residents of the region. Associated environmental media and biomarker (blood, urine) concentration data were also obtained for the study participants to aid in understanding of the relationships of exposures to both contaminant pathways and doses. Besides fulfilling the primary NHEXAS objectives, the NHEXAS data provided an opportunity to explore secondary usages, such as examining pathway to route of exposure relationships. A generic type of structural equation model was used to define the anticipated relationships among the various data types for both arsenic (As) and lead (Pb). Since, by design, only a few participants provided data for all sample types, implementing this model required that some media concentrations (outdoor air and soil) be imputed for subjects with missing information by using measurements collected in the same geographic area and time period. The model, and associated pairwise correlations, generally revealed significant but weak associations among the concentrations, exposures, and doses; the strongest associations occurred for the various air measurements (indoor versus outdoor and personal). The generally weak associations were thought to be partly due to the absence of complete coverage of nonresidential environmental media and to nonsynchronization of relevant measurement times and integration periods of collection across the various sample types. In general, relationships between the NHEXAS questionnaire data and the various concentration, exposure, and body-burden measures were also weak. The model results and the modeling exercise suggest several ways for optimizing the design of future exposure assessment studies that are aimed at supporting structural modeling activities.

Air Pollution↗
PubMed1999

Factors associated with success or failure in radiological interpretation: diagnostic thinking approaches.

RATIONALE AND OBJECTIVES: To identify those radiological diagnostic thinking approaches associated with success or failure in film interpretation. METHODS: A questionnaire was designed, piloted and tested for validity and reliability prior to use. This questionnaire was adapted and modified from the 'diagnostic thinking inventory' by Bordage et al. 21 One hundred and eighty students anonymously answered the questionnaire prior to their 15-case comprehensive film interpretation examination. Oral film-reading sessions were performed on a stratified random sample (n = 48) of students with complete transcripts of each session recorded. Spearman's correlation coefficient and multiple regression analysis statistics were applied to the questionnaire data. The unpaired t-test, ANOVA and correlation statistics were used to analyse the oral film-reading sessions. RESULTS: The most successful students were those who could easily see the integration of radiology with other subjects (P = 0.0042), students who could easily link the clinical information to the radiographic signs (P = 0.0354), and students who could easily identify the 'key' abnormal radiographic findings (P = 0.047). Students who used a flexible but complete search pattern performed significantly better (P = 0.0235) than students using any other search pattern approach. CONCLUSIONS: Radiology is a classic example of clinical problem solving and thus should be taught in that format. Those same factors which differentiate expert from novice diagnosticians are also evident in more successful vs. less successful students in radiology.

Chiropractic↗
PubMed2003

Alveolar bone loss associated with glucose tolerance in Japanese men.

AIMS: Type 2 diabetes is known to affect alveolar bone loss (ABL). The purpose of this study was to examine whether impaired glucose tolerance (IGT) is associated with ABL, as is diabetes. METHODS: A case-control study was performed with 664 Japanese men aged 46-57 years. Panoramic radiographs revealed 513 severe ABL cases, 22 moderate ABL cases, and 129 controls with good alveolar bone. Diabetes status was classified into normal glucose tolerance (NGT), impaired fasting glucose (IFG), IGT, and newly diagnosed diabetes according to the fasting plasma glucose and 75-g oral glucose tolerance test (OGTT). Diabetes under treatment was excluded. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained from ordinal logistic regression analysis. Statistical adjustment was made for total cholesterol, HDL-cholesterol, triglyceride, rank in the Self Defence Forces (SDF), cigarette-years, alcohol use, body mass index, previous 10 years' brushing habits and instrument use other than toothbrush, and history of periodontal treatment. RESULTS: A significant, approximately three-fold increase in the crude OR (crude OR=3.28; 95% CI=1.16-9.27) and non-significant 2.6-fold increase in the adjusted OR (adjusted OR=2.55; 95% CI=0.86, 7.54) of ABL was observed among men with newly diagnosed Type 2 diabetes compared with the reference group (NGT combined with IFG). However, there was no association between IGT and ABL (adjusted OR=0.99; 95% CI=0.59,1.64). CONCLUSIONS: Type 2 diabetes, but not IGT, was positively associated with ABL. Preventive maintenance against periodontitis is important in middle-aged men with diabetes.

Alveolar Bone Loss↗
PubMedDate not supplied

Studies of the sensitivity and reproducibility of commercial kits to detect antibodies to the human immunodeficiency virus.

Nine serial three-fold dilutions (1:1 to 1:6561) were prepared from 18 sera obtained from hemophiliacs confirmed to have antibodies to the human immunodeficiency virus. The dilutions were tested with five different commercial enzyme immunoassay kits and twelve sera were retested 5 to 7 months later by different lots of three kits. The dilution that gave an absorbance (OD) equal to the cut-off OD was considered as the titer of antibody. Sensitivities of the kits were compared by statistical and regression analysis; the same approach was used for studying reproducibility from the results of retesting. The highest titers were found with the Wellcome kit, the lowest with Organon and Pasteur kits, whereas intermediate values were found with the Sorin/Biomedica and Electronucleonics kits. With the Organon and Wellcome kits, excellent reproducibility was observed on later retesting; however, a significant change in titers was seen on retesting the Sorin kit.

Acquired Immunodeficiency Syndrome↗
PubMed1982

Sodium and potassium balances and plasma aldosterone levels in newborn calves.

This paper describes a balance study, performed during the first 7 days of postnatal life on 10 male Holstein x Friesian calves born spontaneously at term. The relationship between sodium and potassium balances and plasma aldosterone levels were assessed during the postnatal period. The animals were put in metabolic cages immediately after birth for 7 days. Intakes of sodium and potassium and their plasma levels, as well as urinary and faecal excretion, were measured daily. Statistical (multiple regression) analysis of the results demonstrated that animal age accounted for 57 p. 100 of the variations observed in the plasma aldosterone levels. Neither intake nor faecal and urinary excretions of sodium and potassium were correlated with plasma aldosterone concentrations in newborn calves. The high plasma levels of this hormone at the time of birth might be a result of labor.

Age Factors↗
PubMed2003

A comparison of the end-tidal CO2 measured by portable capnometer and the arterial PCO2 in spontaneously breathing patients.

An end-tidal CO2 (ETCO2) monitor (capnometer) is used most often as a noninvasive substitute for PaCO2 in anesthesia, anesthetic recovery and intensive care. However, the utility and accuracy of the portable capnometer in spontaneously breathing patients with or without chronic pulmonary diseases has received little recognition. To determine the utility of the portable capnometer in general wards and in in-home care, we examined the correlation between ETCO2 measured by a portable capnometer and simultaneous PaCO2 measured in 41 spontaneously breathing patients. TV-ETCO2 (ETCO2 measured by tidal volume maneuver) was lower than PaCO2 by an average of 9.0 mmHg and VC-ETCO2 (ETCO2 measured by vital capacity maneuver) was lower than PaCO2 by an average of 0.5 mmHg. The mean difference between PaCO2 and VC-ETCO2 was not statistically significant. Regression analysis showed a close correlation between VC-ETCO2 and PaCO2 (r = 0.91, P < 0.0001). Thus,VC-ETCO2 was highly correlated with PaCO2. Furthermore, a close correlation between VC-ETCO2 and PaCO2 was also observed in patients with compromised pulmonary function (r = 0.88, P < 0.0001 in patients with below 70% of FEV(1.0)%; r = 0.89, P < 0.0001 in patients with below 80% of %VC). Our studies show that VC-ETCO2 measured by the portable capnometer gives a reliable pointestimate of PaCO2, and can be useful to evaluate the respiratory condition of spontaneously breathing patients in general wards and in in-home care.

Aged↗
PubMed1980

[Measurement of ophthalmic blood pressure with the Mikuni dynamometer (author's transl)].

Comparative measurements of the ophthalmic arterial blood pressure (Mikuni ophthalmodynamometer) and the systemic blood pressure (Riva-Rocci sphygmomanometer) were carried out in 141 eyes of healthy subjects. There was a linear correlation between the two parameters (p < 0.001). The mean diastolic ophthalmic blood pressure was 58.6 mmHg, the mean systolic blood pressure of 93.4 mmHg. The mean diastolic brachial arterial pressure was 86.7 mmHg, the mean systolic pressure 136 mmHg. In all eyes studied the ophthalmic blood pressure was lower than the ipsilateral brachial blood pressure, in respect of the diastolic as well as of the systolic pressure. On the average the ophthalmic blood pressure was 70% of the systemic blood pressure (mean difference 33.6 mmHg). There was no statistically different regression line between the two parameters in subjects with normal and subjects with elevated systemic blood pressure. In 86% of the paired measurements with the Mikuni ophthalmodynamometer there were differences of less than 5 mmHg in systolic pressure (mean 2.64 mmHg). Correspondingly all differences in diastolic pressure in paired measurements were within 5 mmHg (mean 1.46 mmHg). A difference of 7 mmHg in ophthalmic arterial pressures in an individual appears to be probably pathologic; a difference of more than 9 mmHg seems to be definitely pathologic. In ophthalmodynamometry using the Mikuni instrument a "tonographic effect" occurs, and the intraocular pressure takes 10-15 minutes to return to a physiologically stable state. The extent of this tonographic effect depends on the IOP prior to dynamometry. (p < 0,05).

Adolescent↗
PubMed2004

Two important exceptions to the relationship between energy density and fat content: foods with reduced-fat claims and high-fat vegetable-based dishes.

OBJECTIVE: To test the hypothesis that many foods with reduced-fat (RF) claims are relatively energy-dense and that high-fat (HF) vegetable-based dishes are relatively energy-dilute. DESIGN: Nutrient data were collected from available foods in Melbourne supermarkets that had an RF claim and a full-fat (FF) equivalent. Nutrient analyses were also conducted on recipes for HF vegetable-based dishes that had more than 30% energy from fat but less than 10% from saturated fat. The dietary intake data (beverages removed) from the 1995 National Nutrition Survey were used for the reference relationships between energy density (ED) and percentage energy as fat and carbohydrate and percentage of water by weight. STATISTICS: Linear regression modelled relationships of macronutrients and ED. Paired t-tests compared observed and predicted reductions in the ED of RF foods compared with FF equivalents. RESULTS: Both FF and RF foods were more energy-dense than the Australian diet and the HF vegetable-based dishes were less energy-dense. The Australian diet showed significant relationships with ED, which were positive for percentage energy as fat and negative for percentage energy as carbohydrate. There were no such relationships for the products with RF claims or for the HF vegetable-based dishes. CONCLUSION: While, overall, a reduced-fat diet is relatively energy-dilute and is likely to protect against weight gain, there appear to be two important exceptions. A high intake of products with RF claims could lead to a relatively energy-dense diet and thus promote weight gain. Alternatively, a high intake of vegetable-based foods, even with substantial added fat, could reduce ED and protect against weight gain.

Commerce↗
PubMedDate not supplied

Agent orange and the risk of gestational trophoblastic disease in Vietnam.

There have been claims of an increased risk for gestational trophoblastic disease (i.e., hydatidiform mole and choriocarcinoma) in Vietnam since the period of Agent Orange sprayings. In 1990, we conducted a case-control study in Ho Chi Minh City to investigate risk factors for gestational trophoblastic disease in Vietnam. Eighty-seven married women, all of whom had a recent pathologic diagnosis of gestational trophoblastic disease, identified in the Obstetrical and Gynecological Hospital, were included in the study. Eighty-seven married women who were admitted mainly in the surgery departments of the same hospital were the controls, and they were matched to cases for age and area of residence. Odds ratios (ORs), adjusted for matching variables and other potential confounders, were estimated with unconditional logistic regression. A statistically significant trend in risk was observed with previous live births (p = .01). Cases were found to eat less meat per wk (OR = 0.4, 95% confidence interval [95% CI] = 0.2-0.9 for > or = five meat dishes) and to own fewer consumer goods than controls. An increase in risk was associated with the breeding of pigs (OR = 5.7, 95% CI = 1.2-27.6 for raising three or more pigs). A cumulative Agent Orange exposure index was constructed, using the patient's complete residence history. No significant difference was found between cases and controls for this index (OR = 0.7, 95% CI = 0.2-1.8 for high-exposure category), nor was such a difference noted for the agricultural use of pesticides.

2,4,5-Trichlorophenoxyacetic Acid↗
PubMed2006

Can simple anthropometric and physical performance tests track training-induced changes in maximal box-lifting ability?

The objective of this research was to determine if tests of lifting strength and anthropometry could be used to assess training-induced changes in box-lift performance. Ninety-two British Army recruits completed a 10-week training programme. Isometric and dynamic lifting strength, body composition and maximal box-lift to 1.45 m and 1.70 m were assessed before and after training. Training significantly increased box-lift performance, dynamic lifting strength and fat-free mass, and reduced body fat. Statistically significant regression models (adjusted R(2) of 0.299 and 0.152) were produced that predicted the changes in box-lift performance from changes in body composition and lifting strength. However, the 95% limits of agreement between the observed and predicted change in box-lift performance showed wide margins of error (11-13 kg; 26-29%). Training-induced changes in box-lift performance appear to be highly specific, which suggests that both training and testing procedures should also be specific to box-lift performance.

Adult↗
PubMed1989

Environmental and behavioural factors affecting the prevalence of foot lameness in New Zealand dairy herds - a case-control study.

A case-control study of environmental and behavioural factors influencing foot lameness was undertaken on 62 dairy herds comprising an average of 185 milking cows in Taranaki, New Zealand. Thirty two case herds were identified as having had at least 10 per cent of the cows lame during the milking season in which the herd was studied, and thirty control herds were selected on the basis that no more than 3 per cent of cows in these herds had been lame per year for at least two years immediately prior to investigation. Each herd was visited at both a morning and an afternoon milking, and 58 risk factors were measured between the time the farmer began to assemble the cows for milking and the completion of milking. Comparison of single variables between case and control herds identified 24 which showed differences (p<0.10). These variables were then subjected to stepwise multivariate logistic regression, and statistically significant variables in this analysis were used to create a tentative path diagram of possible causal web relationships between the various risk factors and the outcome variable, the lameness prevalence level. Information from a review of the published literature was used to include further variables to the 24 into the initial (or null hypothesis) path model. Logistic path analysis was then used to eliminate non-significant paths from the diagram, leaving 19 arrows joining 13 variables in the final path diagram, compared with 33 joining 20 variables in the initial version. The most influential variables in explaining variation between case and control herds were the average level of maintenance of the track and the degree of patience shown by the farmer in bringing the cows in for milking. Overall, factors associated with the movement of animals to the milking shed explained 40 per cent of the variation (deviance) with regard to the lameness prevalence level. Risk factors associated with characteristics of the milking process explain 24 per cent, and risk factors associated with characteristics of the cows in the herd explain 9.5 per cent. Recommendations are made on management changes which deserve further investigation as ways of reducing lameness problems in dairy herds.

Journal Article↗
PubMed2005

Decision - delivery interval and perinatal outcome in emergency caesarean sections.

Recent studies have cast doubt on the recommended 30-min decision--delivery interval (DDI) in emergency caesarean sections. The practicability, justification, anticipated beneficial effect on neonatal outcome and its medico-legal implications have been questioned. We set out to determine (1) the DDI for emergency caesarean sections in two Nigerian tertiary care centres (2) the effect of DDI on perinatal outcome (particularly if the DDI is longer than the internationally recommended 30 min) and (3) the factors causing delays in intervention if any. This was a prospective observational study of consecutive cases of emergency caesarean sections performed at the two centres over an 8-month period. The main outcome measures were: indication for the caesarean, the decision-baby delivery interval, 1-min and 5-min Apgar scores, newborn admission to special care, perinatal death and reasons for any delay in decision - delivery interval beyond 30 min. The data were analysed with descriptive and inferential statistics and regression equations at the 95% confidence level. A total of 224 emergency caesarean sections were performed in the two institutions within the period of study. None of the caesarean sections was done within the recommended 30-min interval. Despite this, there was no significant correlation between the DDI and perinatal outcome. The major causes of delays in DDI were anaesthetic delays in both centres and difficulty in sourcing essential materials in one of the centres. The recommended 30-min DDI in emergency caesarean section is not currently feasible in Nigeria. Although the 30-min interval should remain the gold standard, DDI up to 3 hours may not be incompatible with good perinatal outcome as shown in this study. As in other studies, anaesthetic delay is the major cause of delay in carrying out emergency caesarean sections. Finally, since prolonged DDI may not be the cause of an adverse perinatal outcome in the majority of cases, litigation on these grounds may be unjustified.

Adult↗
PubMed2002

Describing functional requirements for knowledge sharing communities.

Human collaboration in distributed knowledge sharing groups depends on the functionality of information and communication technologies (ICT) to support performance. Since many of these dynamic environments are constrained by time limits, knowledge must be shared efficiently by adapting the level of information detail to the specific situation. This paper focuses on the process of knowledge and context sharing with and without mediation by ICT, as well as issues to be resolved when determining appropriate ICT channels. Both technology-rich and non-technology examples are discussed.

Communication↗