Body mass index associations between mother and offspring from birth to age 18: the Fels Longitudinal Study.

BACKGROUND: Parental obesity is a known determinant of childhood obesity. Previous research has shown a strong maternal influence on body mass index (BMI) during infancy and early childhood. OBJECTIVES: The purpose of this research was to investigate the BMI associations between mother and offspring from birth to age 18 years. METHODS: Participants were selected from the Fels Longitudinal Study. The current study sample includes 427 (215 mother/son and 212 mother/daughter) mother/child pairs. These pairs are repeatedly measured at multiple age groups in children, resulting in a total of 6,263 (3,215 mother/son, 3,048 mother/daughter) observations for data analysis. Inclusion criteria were children with measured height and weight for BMI collected at ages 0 to 18 years and their mother with BMI data. Maternal influences of BMI on offspring BMI from birth to early adulthood were analyzed by Spearman correlations and linear regression analyses. RESULTS: Mother/son BMI correlations became statistically significant (p ≤ 0.05) at age 5-6 years and were significant through puberty and into early adulthood at age 18 years. Mother/daughter correlations became significant at age 1.5 years and also continued through adolescence, puberty and early adulthood at age 18 years. Associations persisted after the study sample was grouped into life stages and adjusted for decade of birth and parity. CONCLUSIONS: The mother/daughter relationship was more strongly correlated than the mother/son relationship and also became statistically significant at an earlier age than boys.

Effects of oral temazepam on slow waves during non-rapid eye movement sleep in healthy young adults: A high-density EEG investigation.

Slow waves are characteristic waveforms that occur during non-rapid eye movement (NREM) sleep that play an integral role in sleep quality and brain plasticity. Benzodiazepines are commonly used medications that alter slow waves, however, their effects may depend on the time of night and measure used to characterize slow waves. Prior investigations have utilized minimal scalp derivations to evaluate the effects of benzodiazepines on slow waves, and thus the topography of changes to slow waves induced by benzodiazepines has yet to be fully elucidated. This study used high-density electroencephalography (hdEEG) to evaluate the effects of oral temazepam on slow wave activity, incidence, and morphology during NREM sleep in 18 healthy adults relative to placebo. Temazepam was associated with significant decreases in slow wave activity and incidence, which were most prominent in the latter portions of the sleep period. However, temazepam was also associated with a decrease in the magnitude of high-amplitude slow waves and their slopes in the first NREM sleep episode, which was most prominent in frontal derivations. These findings suggest that benzodiazepines produce changes in slow waves throughout the night that vary depending on cortical topography and measures used to characterize slow waves. Further research that explores the relationships between benzodiazepine-induced changes to slow waves and the functional effects of these waveforms is indicated.

Effects of oral temazepam on sleep spindles during non-rapid eye movement sleep: A high-density EEG investigation.

Benzodiazepines are commonly used medications that alter sleep spindles during non-rapid eye movement (NREM) sleep, however the topographic changes to these functionally significant waveforms have yet to be fully elucidated. This study utilized high-density electroencephalography (hdEEG) to investigate topographic changes in sleep spindles and spindle-range activity caused by temazepam during NREM sleep in 18 healthy adults. After an accommodation night, sleep for all participants was recorded on two separate nights after taking either placebo or oral temazepam 15 mg. Sleep was monitored using 256-channel hdEEG. Spectral analysis and spindle waveform detection of sleep EEG data were performed for each participant night. Global and topographic data were subsequently compared between temazepam and placebo conditions. Temazepam was associated with significant increases in spectral power from 10.33 to 13.83 Hz. Within this frequency band, temazepam broadly increased sleep spindle duration, and topographically increased spindle amplitude and density in frontal and central-posterior regions, respectively. Higher frequency sleep spindles demonstrated increased spindle amplitude and a paradoxical decrease in spindle density in frontal and centroparietal regions. Further analysis demonstrated temazepam both slowed the average frequency of spindle waveforms and increased the relative proportion of spindles at peak frequencies in frontal and centroparietal regions. These findings suggest that benzodiazepines have diverse effects on sleep spindles that vary by frequency and cortical topography. Further research that explores the relationships between topographic and frequency-dependent changes in pharmacologically-induced sleep spindles and the functional effects of these waveforms is indicated.

Evaluation of Fall Recovery and Gait Adaptation to Medial and Lateral Gait Perturbations.

The aim of this study was to develop an active gait perturbation system and to evaluate its efficacy in evaluating fall recovery and gait adaptation. We hypothesized that a translating perturbation during the single stance phase would alter gait adaptations, in terms of gait parameters and muscle co-contractions, during recovery to maintain dynamic stability for continued walking. A customized miniature treadmill, built on a large force plate and embedded perpendicular to the walkway, was used to translate the loaded stance foot medially and laterally to interrupt swing foot trajectory. The perturbation was activated when the stepping foot was placed entirely on the belt to ensure the foot would remain on the belt when translated. The translating floor surface was applied to 10 young, healthy adult subjects (5 males, 5 females; aged <35y) during normal walking at their preferred speed. Step length, step width, step duration, and muscle co-contraction at the ankle of the stance limb was examined before, during, and after both the medial and lateral translations. Shorter step length, wider step width, faster step duration, and higher muscle co-contraction at the ankle joint were observed strategies for fall recovery and regaining body stability.

Topographic and sex-related differences in sleep spindles in major depressive disorder: a high-density EEG investigation.

BACKGROUND: Sleep spindles are believed to mediate several sleep-related functions including maintaining disconnection from the external environment during sleep, cortical development, and sleep-dependent memory consolidation. Prior studies that have examined sleep spindles in major depressive disorder (MDD) have not demonstrated consistent differences relative to control subjects, which may be due to sex-related variation and limited spatial resolution of spindle detection. Thus, this study sought to characterize sleep spindles in MDD using high-density electroencephalography (hdEEG) to examine the topography of sleep spindles across the cortex in MDD, as well as sex-related variation in spindle topography in the disorder. METHODS: All-night hdEEG recordings were collected in 30 unipolar MDD participants (19 women) and 30 age and sex-matched controls. Topography of sleep spindle density, amplitude, duration, and integrated spindle activity (ISA) were assessed to determine group differences. Spindle parameters were compared between MDD and controls, including analysis stratified by sex. RESULTS: As a group, MDD subjects demonstrated significant increases in frontal and parietal spindle density and ISA compared to controls. When stratified by sex, MDD women demonstrated increases in frontal and parietal spindle density, amplitude, duration, and ISA; whereas MDD men demonstrated either no differences or decreases in spindle parameters. LIMITATIONS: Given the number of male subjects, this study may be underpowered to detect differences in spindle parameters in male MDD participants. CONCLUSIONS: This study demonstrates topographic and sex-related differences in sleep spindles in MDD. Further research is warranted to investigate the role of sleep spindles and sex in the pathophysiology of MDD.

Is diabetes associated with poorer self-efficacy and motivation for physical activity in older adults with arthritis?

OBJECTIVES: The primary aim was to explore whether arthritis is associated with poorer self-efficacy and motivation for, and participation in, two specific types of physical activity (PA): endurance training (ET) and strength training (ST). A further objective was to determine whether the added burden of diabetes contributes to a further reduction in these PA determinants and types. METHODS: Self-efficacy and motivation for exercise and minutes per week of ET and ST were measured in 347 older veterans enrolled in a home-based PA counselling intervention. Regression analyses were used to compare high versus low self-efficacy and motivation and PA minutes in persons without arthritis, with arthritis alone, and with arthritis plus diabetes. RESULTS: Persons with arthritis alone reported lower self-efficacy for ET and ST than those without arthritis [odds ratio (OR)ET 0.71, 95% confidence interval (CI) 0.39­1.20; ORST 0.69, 95% CI 0.39­1.20]. A further reduction in self-efficacy for these two types of PA was observed for those with both arthritis and diabetes (ORET 0.65, 95% CI 0.44­0.92; ORST 0.64, 95% CI 0.44­0.93; trend p < 0.001). There was no trend towards a reduction in motivation for PA in those with arthritis alone or with arthritis and diabetes. Persons with arthritis exhibited higher motivation for ET than those without arthritis (ORET 1.85, 95% CI 1.12­3.33). There were no significant differences between the three groups in minutes of ET (p = 0.93), but persons with arthritis plus diabetes reported significantly less ST compared to individuals with arthritis only (p = 0.03). CONCLUSIONS: Despite reduced self-efficacy for ET and ST and less ST in older persons with arthritis, motivation for both PA types remains high, even in the presence of diabetes.

The impact of self-reported arthritis and diabetes on response to a home-based physical activity counselling intervention.

OBJECTIVES: Physical activity (PA) has the potential to improve outcomes in both arthritis and diabetes, but these conditions are rarely examined together. Our objective was to explore whether persons with arthritis alone or those with both arthritis and diabetes could improve amounts of PA with a home-based counselling intervention. METHODS: As part of the Veterans LIFE (Learning to Improve Fitness and Function in Elders) Study, veterans aged 70-92 were randomized to usual care or a 12-month PA counselling programme. Arthritis and diabetes were assessed by self-report. Mixed models were used to compare trajectories for minutes of endurance and strength training PA for persons with no arthritis (n = 85), arthritis (n = 178), and arthritis plus diabetes (n = 84). RESULTS: Recipients of PA counselling increased minutes of PA per week independent of disease status (treatment arm by time interaction p < 0.05 for both; endurance training time p = 0.0006 and strength training time p < 0.0001). Although PA was lower at each wave among persons with arthritis, and even more so among persons with arthritis plus diabetes, the presence of these conditions did not significantly influence response to the intervention (arthritis/diabetes group x time interactions p > 0.05 for both outcomes) as each group experienced a nearly twofold or greater increase in PA. CONCLUSIONS: A home-based PA intervention was effective in increasing minutes of weekly moderate intensity endurance and strength training PA in older veterans, even among those with arthritis or arthritis plus diabetes. This programme may serve as a useful model to improve outcomes in older persons with these pervasive diseases.

A direct demonstration of cortical LTP in humans: a combined TMS/EEG study.

Repetitive transcranial magnetic stimulation (rTMS) is increasingly being used to promote cortical reorganization, under the assumption that it can induce long-term potentiation (LTP) of neural responses. This assumption is supported by several lines of indirect evidence. For example, rTMS of motor cortex can induce a potentiation of muscle motor evoked potentials that outlasts the stimulation by several minutes. In animal models, a direct demonstration of LTP is typically obtained by high-frequency electrical stimulation coupled with local field recordings of population responses. In this study, we exploited a new approach based on combined rTMS/high-density electroencephalography (hd-EEG) to obtain direct, noninvasive evidence for LTP in humans. Cortical responses to single TMS pulses were measured with hd-EEG before and after applying rTMS to motor cortex (5Hz, 1500 pulses). The results demonstrate that, after rTMS, EEG responses at latencies of 15-55ms were significantly potentiated. A topographic analysis revealed that this potentiation was significant at EEG electrodes located bilaterally over premotor cortex. Thus, these findings provide a direct demonstration in humans of LTP induced by rTMS.

Trace element contamination in benthic macroinvertebrates from a small stream near a uranium mill tailings site.

Direct measurement of the accumulation of non-radioactive trace elements in aquatic biota near uranium mining or processing sites has been relatively rare, with greater focus on the radiological activity in the adjacent soils and groundwater. To evaluate the potential ecological concern associated with trace elements at a former uranium mill site in southeastern Utah, benthic macroinvertebrates were collected and analyzed for 17 trace elements from multiple locations within a small on-site stream, Montezuma Creek, and a nearby reference stream. Key questions of this study relate to the spatial and temporal extent of contamination in aquatic biota, the potential ecological risks associated with that contamination, and the usefulness of benthic macroinvertebrates as a monitoring tool at this site. Composite samples of similar macroinvertebrate taxa and functional feeding groups were collected from each site over a two year period that was representative of normal and dry-year conditions. In both years, mean concentrations of arsenic, molybdenum, selenium, and vanadium were significantly higher (a factor of 2-4 times: P < 0.05) in macroinvertebrates collected from one or both of the two Montezuma Creek sites immediately downstream of the mill tailing site in comparison to concentrations from reference locations. Mean uranium concentrations in invertebrates immediately downstream of the mill site were more than 10 times higher than at reference sites. The site-to-site pattern of contamination in Montezuma Creek invertebrates was similar in 1995 and 1996, with mill-related trace elements showing a downstream decreasing trend. However, nine of seventeen contaminant concentrations were higher in the second year of the study, possibly due to a higher influx of deep groundwater during the drier second year of the study. A preliminary assessment of ecological risks, based on the benthic macroinvertebrate bioaccumulation data, suggests that aquatic and terrestrial population risks are low. Benthic macroinvertebrates appeared to be sensitive integrators of trace element inputs to the aquatic environment from a former uranium mill tailing site, and provided useful spatial and temporal patterns of contamination not easily obtained using conventional surface water or groundwater measures.

Spatial associations among density of cattle, abundance of wild canids, and seroprevalence to Neospora caninum in a population of beef calves.

OBJECTIVE: To determine the epidemiologic plausibility of a sylvatic transmission cycle for Neospora caninum between wild canids and beef cattle. DESIGN: Spatial analysis study. ANIMALS: 1,009 weaned beef steers from 94 beef herds in Texas. PROCEDURE: Calves were grouped on the basis of seroprevalence for N caninum and ecologic region in Texas. The Morans I test was used to evaluate spatial interdependence for adjusted seroprevalence by ecologic region. Cattle density (Number of cattle/259 km2 [Number of cattle/100 mile2] of each ecologic region) and abundance indices for gray foxes and coyotes (Number of animals/161 spotlight-transect [census] km [Number of animals/100 census miles] of each ecologic region) were used as covariates in spatial regression models, with adjusted seroprevalence as the outcome variable. A geographic information system (GIS) that used similar covariate information for each county was used to validate spatial regression models. Results-Spatial interdependence was not detected for ecologic regions. Three spatial regression models were tested. Each model contained a variable for cattle density for the ecologic regions. Results for the 3 models revealed that seroprevalence was associated with cattle density and abundances of gray foxes, coyotes, or both. Abundances of gray foxes and coyotes were collinear. Results of a GIS-generated model validated these spatial models. CONCLUSIONS AND CLINICAL RELEVANCE: In Texas, beef cattle are at increased risk of exposure to N caninum as a result of the abundance of wild canids and the density of beef cattle. It is plausible that a sylvatic transmission cycle for neosporosis exists.

Human myeloid zinc finger gene MZF produces multiple transcripts and encodes a SCAN box protein.

The myeloid zinc finger gene 1 (MZF1) encodes a C(2)H(2) zinc finger transcription factor that regulates granulopoiesis and may have a regulatory role in cellular proliferation and oncogenesis. The MZF1 gene has been previously reported to be 3kb and without introns. However, at least three transcripts of approximately 3, 7.5, and 9kb are detected by MZF1-specific probes in northern blot analysis and the identity of the transcripts has not been addressed. We screened a K562 cDNA library and identified novel transcripts, MZF1B and MZF1C. The 2.9kb MZF1B cDNA encodes a putative 734 aa protein and MZF1C maintains an identical open reading frame with 320 nucleotides deleted in the 5'-untranslated region. The MZF1B/1C protein contains all but the first eight amino acids of MZF1. Thus, MZF protein isoforms share 100 aa, as well as the bipartite 13 zinc finger DNA binding domain. In addition, MZF1B/1C encodes a unique 257 aa MZF1B/C amino terminus containing a SCAN box, or leucine-rich domain, which has recently been demonstrated to facilitate protein interactions. Sequence analysis reveals that the MZF gene contains six exons and spans 11kb and may be the most telomeric gene on chromosome 19q13. Exons 1-6 produce MZF1B/C cDNA, whereas MZF1 cDNA initiates within intron 5 and continues through exon 6. The 7.5 and 9kb transcripts are incompletely processed and contain intron sequences. These studies are the first description of the complete human MZF gene and of the composition of the multiple transcripts that are detected by northern blot analysis.

Long-term increased bioaccumulation of mercury in largemouth bass follows reduction of waterborne selenium.

Average mercury concentrations in largemouth bass from Rogers Quarry in east Tennessee were found to increase steadily following the elimination of selenium-rich discharges of fly ash to the quarry in 1989. From 1990 to 1998, mean mercury concentrations (adjusted to compensate for the covariance between individual fish weight and mercury concentration) in bass rose from 0.02 to 0.61 mg/kg. There was no indication that the rate increase was slowing or that mercury concentrations in fish were approaching a plateau or steady state. Mean selenium concentrations in bass declined from 3 to 1 mg/kg over the first five years of the study, but remained at 1-1.5 mg/kg (about twice typical concentrations in bass from local reference sites) for the last three years of the study. Gross physical abnormalities were common in fish from the site in the first three years after elimination of fly ash discharges but disappeared after two more years. Although it remains possible that other chemical or physical changes related to fly ash disposal in the system were associated with increased mercury bioaccumulation, the most likely explanation is that selenium played a critical role. It appears as though aqueous selenium enrichment was capable of having a profound effect on mercury bioaccumulation in this system but at the cost of causing a high incidence of gross abnormalities in fish. However, it is possible that selenium concentrations between the national ambient water quality criterion for the protection of aquatic life, 5 microg/l, and that now found in Rogers Quarry (<2 microg/l) could reduce mercury bioaccumulation without causing adverse effects on aquatic biota and fish-eating wildlife.

Identification of a novel SCAN box-related protein that interacts with MZF1B. The leucine-rich SCAN box mediates hetero- and homoprotein associations.

The SCAN box or leucine-rich (LeR) domain is a conserved motif found within a subfamily of C(2)H(2) zinc finger proteins. The function of a SCAN box is unknown, but it is predicted to form alpha-helices that may be involved in protein-protein interactions. Myeloid zinc finger gene-1B (MZF1B) is an alternatively spliced human cDNA isoform of the zinc finger transcription factor, MZF1. MZF1 and MZF1B contain 13 C(2)H(2) zinc finger motifs, but only MZF1B contains an amino-terminal SCAN box. A bone marrow cDNA library was screened for proteins interacting with the MZF1B SCAN box domain and RAZ1 (SCAN-related protein associated with MZF1B) was identified. RAZ1 is a novel cDNA that encodes a SCAN-related domain and arginine-rich region but no zinc finger motifs. Co-immunoprecipitation assays demonstrate that the SCAN box domain of MZF1B is necessary for association with RAZ1. By yeast two-hybrid analysis, the carboxyl terminus of RAZ1 is sufficient for interaction with the MZF1B SCAN box. Furthermore, MZF1B and RAZ1 each self-associate in vitro via a SCAN box-dependent mechanism. These data provide evidence that the SCAN box is a protein interaction domain that mediates both hetero- and homoprotein associations.

Combining the arts: an applied critical thinking approach in the skills laboratory.

The quality of care that nurses provide to patients is strongly influenced by the nurses' ability to think critically and to solve problems. In response to the dynamic changes in healthcare and rapid technological advancements, nursing educators must prepare nursing students to meet the challenges. Baccalaureate nursing students must be taught to utilize critical thinking skills for problem solving during the application of the nursing process. Nursing students who use critical thinking skills will provide high quality and efficient patient care in the acute care and community settings. During the simulated laboratory experience, incorporating creative teaching strategies to promote critical thinking and enhance problem-solving skills can enable nursing graduates to enter the workforce feeling confident and competent.

Determinants of retinopathy progression in type 1 diabetes mellitus.

PURPOSE: To determine the risk factors for retinopathy progression in type 1 (insulin-dependent) diabetes mellitus in a prospective cohort study. SUBJECTS AND METHODS: Subjects were 485 participants in the Sorbinil Retinopathy Trial, a randomized trial of aldose reductase inhibition among patients aged 18 to 56 years with type 1 diabetes mellitus (duration of 1 to 15 years) and no or only mild retinopathy. Retinopathy progression, assessed by seven-field stereoscopic fundus photography, was defined as worsening by two or more levels on a standardized grading scale at the end of follow-up (median, 41 months). RESULTS: The relative risks for retinopathy progression according to successively greater quintiles of total glycosylated hemoglobin level at baseline, after adjusting for age, diabetes duration, sorbinil assignment, and other variables, were 1.0, 2.0, 1.6, 3.7, and 4.4 (P trend <0.0001). Risk increased with greater baseline diastolic blood pressure: 1.0 for <70 mm Hg, 1.2 for 70 to 79 mm Hg, and 1.8 for > or =80 mm Hg (P for trend = 0.04). Diastolic blood pressure was a significant risk factor for progression in participants with mild baseline retinopathy (P for trend <0.02) but not in those without retinopathy at entry. Systolic blood pressure, by comparison, was not associated with progression. Baseline total cholesterol level was a marginally significant predictor of retinopathy progression when examined as a categorical variable (relative risks for increasing quartiles; 1.0, 1.6, 1.8, 1.9; P for trend = 0.03) but not when it was examined as a continuous variable or when hypercholesterolemic patients were compared with those with normal levels. Furthermore, when cholesterol levels were updated in subsequent visits, it was not a significant predictor of progression, and low density lipoprotein (LDL) cholesterol levels did not predict progression no matter how analyzed. Smoking was not associated with progression of retinopathy. CONCLUSIONS: Levels of hyperglycemia and diastolic blood pressure predicted progression of retinopathy in type 1 diabetes mellitus. We found only a suggestion of an association between total cholesterol level (but not of LDL cholesterol level) and progression of retinopathy; resolution of this issue will require additional studies with larger sample sizes and longer follow-up.

Age, testing at preferred or nonpreferred times (testing optimality), and false memory.

Two experiments investigated whether age and testing at preferred (optimal) times of day or nonpreferred (nonoptimal) times affected the ability to select relevant from irrelevant but thematically related alternatives in a verbal false memory paradigm. A 3rd experiment pursued the same issues with a visual false memory paradigm. In all 3 experiments, younger adults (n = 195) correctly recalled studied items more often than older adults (n = 121), whereas the 2 age groups correctly recognized about the same numbers of previously studied items. In all 3 experiments, nonoptimally tested older adults had more difficulty excluding nonstudied but thematically related items than the other groups; thus, they showed the greatest evidence of false memory, although all groups did so to a significant extent. The results suggest that optimality and its circadian determinants need to be considered with some tasks for the elderly. Various models and mechanisms are discussed.

Northern bobwhites as disease indicators for the endangered Attwater's prairie chicken.

Because of limited access to the endangered Attwater's prairie chicken (Tympanuchus cupido attwateri), we used a related species, the northern bobwhite (Colinus virginianus), as a surrogate for disease evaluation. Free-living northern bobwhites (n = 62) on the Attwater Prairie Chicken National Wildlife Refuge (near Eagle Lake, Texas, USA) were examined during spring and fall 1993 for helminthic endoparasites and specific antibodies against the infectious agents responsible for nine infectious diseases. Trichostrongylus cramae, Raillietina sp., and Strongyloides avium were collected from 97, 44, and 32% of northern bobwhites examined, respectively. Dispharynx nasuta and Syngamus trachea also were found. No gross lesions due to parasites were observed. Specific antibody to Pasteurella multocida was found in 3 of 53 plasma samples. It is possible that potentially pathogenic species such as P. multocida, T. cramae, and D. nasuta could threaten sympatric Attwater's prairie chickens.