We provide an updated version of the Compendium of Physical Activities, a coding scheme that classifies specific physical activity (PA) by rate of energy expenditure. It was developed to enhance the ...comparability of results across studies using self-reports of PA. The Compendium coding scheme links a five-digit code that describes physical activities by major headings (e.g., occupation, transportation, etc.) and specific activities within each major heading with its intensity, defined as the ratio of work metabolic rate to a standard resting metabolic rate (MET). Energy expenditure in MET-minutes, MET-hours, kcal, or kcal per kilogram body weight can be estimated for specific activities by type or MET intensity. Additions to the Compendium were obtained from studies describing daily PA patterns of adults and studies measuring the energy cost of specific physical activities in field settings. The updated version includes two new major headings of volunteer and religious activities, extends the number of specific activities from 477 to 605, and provides updated MET intensity levels for selected activities.
This study was designed to establish prediction models that relate hip and wrist accelerometer data to energy expenditure (EE) in field and laboratory settings. We also sought to determine whether ...the addition of a wrist accelerometer would significantly improve the prediction of EE (METs), compared with a model that used a hip accelerometer alone.
Seventy participants completed one to six activities within the categories of yardwork, housework, family care, occupation, recreation, and conditioning, for a total of 5 to 12 participants tested per activity. EE was measured using the Cosmed K4b2 portable metabolic system. Simultaneously, two Computer Science and Applications, Inc. (CSA) accelerometers (model 7164), one worn on the wrist and one worn on the hip, recorded body movement. Correlations between EE measured by the Cosmed and the counts recorded by the CSA accelerometers were calculated, and regression equations were developed to predict EE from the CSA data.
The wrist, hip, and combined hip and wrist regression equations accounted for 3.3%, 31.7%, and 34.3% of the variation in EE, respectively. The addition of the wrist accelerometer data to the hip accelerometer data to form a bivariate regression equation, although statistically significant (P = 0.002), resulted in only a minor improvement in prediction of EE. Cut points for 3 METs (574 hip counts), 6 METs (4945 hip counts), and 9 METs (9317 hip counts) were also established.
The small amount of additional accuracy gained from the wrist accelerometer is offset by the extra time required to analyze the data and the cost of the accelerometer.
Analysis of adolescent idiopathic scoliosis (AIS) requires a thorough clinical and radiographic evaluation to completely assess the three-dimensional deformity. Recently, these radiographic ...parameters have been analyzed for reliability and reproducibility following manual measurements; however, most of these parameters have not been analyzed with regard to digital measurements. The purpose of this study is to determine the intra- and interobserver reliability of common scoliosis radiographic parameters using a digital software measurement program.
Thirty sets of preoperative (posteroanterior PA, lateral, and side-bending SB) and postoperative (PA and lateral) radiographs were analyzed by three independent observers on two separate occasions using a software measurement program (PhDx, Albuquerque, NM). Coronal measures included main thoracic (MT) and thoracolumbar-lumbar (TL/L) Cobb, SB MT Cobb, MT and TL/L apical vertical translation (AVT), C7 to center sacral vertical line (CSVL), T1 tilt, LIV tilt, disk below lowest instrumented vertebra (LIV), coronal balance, and Risser, whereas sagittal measures included T2-T5, T5-T12, T2-T12, T10-L2, T12-S1, and sagittal balance. Analysis of variance for repeated measures or Cohen three-way kappa correlation coefficient analysis was performed as appropriate to calculate the intra- and interobserver reliability for each parameter.
The majority of the radiographic parameters assessed demonstrated good or excellent intra- and interobserver reliability. The relationship of the LIV to the CSVL (intraobserver kappaa = 0.48-0.78, fair to excellent; interobserver kappaa = 0.34-0.41, fair to poor), interobserver measurement of AVT (rho = 0.49-0.73, low to good), Risser grade (intraobserver rho = 0.41-0.97, low to excellent; interobserver rho = 0.60-0.70, fair to good), intraobserver measurement of the angulation of the disk inferior to the LIV (rho = 0.53-0.88, fair to good), apical Nash-Moe vertebral rotation (intraobserver rho = 0.50-0.85, fair to good; interobserver rho = 0.53-0.59, fair), and especially regional thoracic kyphosis from T2 to T5 (intraobserver rho = 0.22-0.65, poor to fair; interobserver rho = 0.33-0.47, low) demonstrated lesser reliability. In general, preoperative measures demonstrated greater reliability than postoperative measures, and coronal angular measures were more reliable than sagittal measures.
Most common radiographic parameters for AIS assessment demonstrated good or excellent reliability for digital measurement and can be recommended for routine clinical and academic use. Preoperative assessments and coronal measures may be more reliable than postoperative and sagittal measurements. The reliability of digital measurements will be increasingly important as digital radiographic viewing becomes commonplace.
Three methods for measuring time spent in daily physical activity (PA) were compared during a 21-d period among 83 adults (38 men and 45 women).
Each day, participants wore a Computer Science and ...Applications, Inc. (CSA) monitor and completed a 1-page, 48-item PA log that reflected time spent in household, occupational, transportation, sport, conditioning, and leisure activities. Once a week, participants also completed a telephone survey to identify the number of minutes spent each week in nonoccupational walking and in moderate intensity and hard/very hard-intensity PA. Data were analyzed using descriptive statistics and Spearman rank-order correlations. Three equations developed to compute CSA cut points for moderate and hard/very hard PA were also compared with the PA logs and PA survey.
There was modest to good agreement for the time spent in different PA intensity categories between the three CSA cut point methods (r = 0.43-0.94, P < 0.001). Correlations between the CSA and PA logs ranged from r = 0.22 to r = 0.36, depending on the comparisons. Correlations between the survey items and PA logs were r = 0.26-0.54 (P < 0.01) for moderate and walking activities and r < 0.09 (P > 0.05) for hard/very hard activities. Correlations between the survey items and the CSA min per day varied according to the method used to compute the CSA intensity cut points.
The results were consistent with findings from other PA validation studies that show motion sensors, PA logs, and surveys reflect PA; however, these methods do not always provide similar estimates of the time spent in resting/light, moderate, or hard/very hard PA.
To further develop our understanding of the relationship between habitual physical activity and health, research studies require a method of assessment that is objective, accurate, and noninvasive. ...Heart rate (HR) monitoring represents a promising tool for measurement because it is a physiological parameter that correlates well with energy expenditure (EE). However, one of the limitations of HR monitoring is that training state and individual HR characteristics can affect the HR-VO2 relationship.
The primary purpose of this study was to examine the relationship between HR (beats x min(-1)) and VO2 (mL x kg(-1 x -1) min(-1)) during field- and laboratory-based moderate-intensity activities. In addition, we examined the validity of estimating EE from HR after adjusting for age and fitness. This was done by expressing the data as a percent of heart rate reserve (%HRR) and percent of VO2 reserve (%VO2R).
Sixty-one adults (18-74 yr) performed physical tasks in both a laboratory and field setting. HR and VO2 were measured continuously during the 15-min tasks. Mean values over min 5-15 were used to perform linear regression analysis on HR versus VO2. HR data were then used to predict EE (METs), using age-predicted HRmax and estimated VO2max.
The correlation between HR and VO2 was r = 0.68, with HR accounting for 47% of the variability in VO2. After adjusting for age and fitness level, HR was an accurate predictor of EE (r = 0.87, SEE = 0.76 METs).
This method of analyzing HR data could allow researchers to more accurately quantify physical activity in free-living individuals.
Twin, family and adoption studies have suggested that vulnerability to opioid dependence may be a partially inherited trait (Cadoret et al., 1986; Merikangas et al., 1998; Tsuang et al., 1998, 2001). ...Studies using animal models also support a role for genetic factors in opioid dependence, and point to a locus of major effect on mouse chromosome 10 (Berrettini et al., 1994; Alexander et al., 1996), which harbors the mu opioid receptor gene (Mor1) (Kozak et al., 1994). The gene encoding the human mu opioid receptor (OPRM1) is thus an obvious candidate gene for contributing to opioid dependence. A recent report (Hoehe et al., 2000) found a significant association between a specific combination of OPRM1 single nucleotide polymorphisms (SNPs) and substance dependence.
In the current study, we genotyped 213 subjects with severe opioid dependence (89 African-Americans, 124 European-Americans) and 196 carefully screened "supercontrol" subjects (96 African-Americans, 100 European-Americans) at five SNPs residing in the OPRM1 gene. The polymorphisms include three in the promoter region (T-1793A, -1699T insertion and A-1320G) and two in exon 1 (C+17T Ala6Val and A+118G Asp40Asn).
Statistical analysis of the allele frequency differences between opioid-dependent and control subjects for each of the polymorphisms studied yielded P values in the range of 0.444-1.000. Haplotype analysis failed to identify any specific combination of SNPs associated with the phenotype.
Despite reasonable statistical power we found no evidence of association between the five mu opioid receptor polymorphisms studied and severe opioid dependence in our sample. There were, however, significant allele frequency differences between African-Americans and European-Americans for all five polymorphisms, irrespective of drug-dependent status. Linkage disequilibrium analysis of the African-American genotypes indicated linkage disequilibrium (P<0.0001) across the five-polymorphism, 1911 base pair region. In addition, only four haplotypes of these five polymorphisms are predicted to exist in African-Americans.
The prodynorphin gene (PDYN) promoter has a repeat polymorphism that is functionally important in association with substance abuse. We examined this polymorphism for association in our sample of 168 ...opioid-dependent patients and 122 ethnically and geographically matched controls.
Patients were selected from university-affiliated residential and non-residential addiction treatment programs in the Philadelphia area. A sample of blood was drawn from consenting individuals and genomic DNA was isolated. Polymerase chain reaction amplification of the PDYN promoter was performed and various genotypes were determined on the basis of differing sizes of the polymerase chain reaction products. The genotype and allele data were analyzed by Fisher's exact test.
A significant difference in genotype (P<0.0006) and allele (P<10) frequencies was found between the African American and European American populations. We did not detect any significant difference in genotype or allele frequencies between the patients and controls within the European American ethnic group. However, we detected a weak association (P=0.013) when we compared allele frequencies of patients and controls in the African American population.
These data suggest that the PDYN repeat polymorphism should be studied in additional opioid-dependent populations.
The influence of beta-chain diversity on the expressed T-cell receptor (TCR) alpha-chain repertoire was investigated using transgenic mice which exclusively express a single rearranged TCR beta-chain ...gene. Analysis of these mice using alpha-chain-specific recombinant cDNA libraries showed that expression of the transgene-encoded beta chain results in significant skewing in Tcra-V gene segment usage vs nontransgenic mice. Skewing was most pronounced towards alpha chains using TCRA-V segments. Sequence analysis of Tcra-V8-containing genes from transgenic T cells revealed predominant use of a single Tcra-J segment (Tcra-J24), which was not detected in Tcra-V8 containing genes isolated from nontransgenic T cells. Further analysis revealed that co-expression of Tcra-V8 with Tcra-J24 in beta-transgenic mice is exhibited almost exclusively by CD4+ T cells, and is associated with a limited number of closely related N-regions. Analysis of transgenic CD8+ T cells demonstrated predominant co-expression of Tcra-V8 with another Tcra-J (Tcra-J30), together with a different, limited N-region sequence. We conclude that the composition of expressed beta chains can profoundly influence the selection of companion alpha chains expressed in the periphery, and that alpha-chain N and J regions play a crucial role in discriminating between class I vs class II major histocompatibility complex (MHC)-restricted recognition. Further, these results are in agreement with recent data concerning the crystal structure of the TCR, and most consistent with a model for TCR structure in which the complementarity determining region (CDR)3alpha domain participates in direct contact with the MHC.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
