Search

Two masked priming experiments examined behavioural and event-related potential responses to simplex target words (e.g., flex) preceded by briefly presented, masked, derived word primes (flexible-flex), complex nonword primes formed by an illegal combination of the target word and a real suffix (flexify-flex), and simplex nonword primes formed by adding a nonsuffix word ending to the target (flexint-flex). Subjects performed a lexical decision task. Behavioural results showed that all prime types significantly facilitated target recognition. Priming effects were reflected in the electrophysiological data by reduced N250 and N400 amplitudes, and these priming effects were statistically equivalent for the three types of prime. The strong priming effects found with simplex primes in the present study, compared with prior research, are thought to be due to the combination of targets always being completely embedded in prime stimuli plus the reduced lexical inhibition that arises with nonword primes. In line with prior behavioural research, however, there was evidence for differential priming effects as a function of prime type in the N400 ERP component in Experiment 2, with greater priming effects for derived and pseudocomplex primes relative to simplex primes at lateral posterior electrode sites. [ABSTRACT FROM AUTHOR]

Dried blood spot (DBS) methodology offers significant advantages over venipuncture in studies of vulnerable populations or large-scale studies, including reduced participant burden and higher response rates. Uncertainty about the validity of cardiovascular disease (CVD) risk biomarkers remains a barrier to wide-scale use. We determined the validity of DBS-derived biomarkers of CVD risk versus gold-standard assessments, and study-specific, serum-equivalency values for clinical relevance of DBS-derived values. Concurrent venipuncture serum and DBS samples (n= 150 adults) were assayed in Clinical Laboratory Improvement Amendments–certified and DBS laboratories, respectively. Time controls of DBS standard samples were assayed single-blind along with test samples. Linear regression analyses evaluated DBS-to-serum equivalency values; agreement and bias were assessed via Bland-Altman plots. Linear regressions of venipuncture values on DBS-to-serum equivalencies provided R2values for total cholesterol, high-density lipoprotein cholesterol (HDL-C), and C-reactive protein (CRP) of 0.484, 0.118, and 0.666, respectively. Bland-Altman plots revealed minimal systematic bias between DBS-to-serum and venipuncture values; precision worsened at higher mean values of CRP. Time controls revealed little degradation or change in analyte values for HDL-C and CRP over 30 weeks. We concluded that DBS-assessed biomarkers represent a valid alternative to venipuncture assessments. Large studies using DBS should include study-specific serum-equivalency determinations to optimize individual-level sensitivity, the viability of detecting intervention effects, and generalizability in community-level primary prevention interventions. [ABSTRACT FROM AUTHOR]

The spectroscopic acetyl bromide lignin (ABL) and two versions of the gravimetric sulfuric acid lignin method [Lignin (sa)] were compared for their correlations with in vitro forage dry matter (IVDMD) and neutral detergent fiber degradability (IVNDFD) assays of 73 grass and legume samples. The two versions of Lignin (sa) were the acid detergent lignin (ADL) and Klason lignin (KL) methods. ABL and KL methods employ crude cell wall as the fibrous preparation while ADL uses acid detergent fiber. In vitro forage measures of degradability were negatively correlated with almost all lignin values, but the ABL method had the highest correlation coefficients for both grasses and legumes. Regression curves of ADL values with grass and legume IVDMD and IVNDF revealed different slopes, with steeper curves for grasses. With KL, grass and legume IVDMD and IVNDFD slopes were statistically similar and parallel. The results observed in the ADL and KL methods testify to the distance between the lines and data points, that is, these methods are poor predictors of NDF degradability. Grass and legume samples assayed with the ABL procedure, exhibited similar slopes, with parallel lines for both IVDMD and IVNDFD assays. Steeper inclination of curve for grasses relative to legumes in the ADL method may be attributed to partial loss of lignin during the procedure. This shows that ABL can accurately and consistently measure the inhibitory effect of lignin on degradation of structural carbohydrates of both grasses and legumes. The ABL method provides an accurate, easy and fast procedure for quantifying lignin in plant materials. A step-by-step laboratory procedure of the ABL method is described. [ABSTRACT FROM AUTHOR]

The article discusses a study conducted to determine the correlations between sleep deficiency and perceived pain, functional limitations and physical limitations in hospital patient care workers. The results proved that sleep deficiency is usually caused by higher rates of pain, work interference and functional limitations. It recommends the use of multilevel interventions for supporting changes in individual workers.

The rumen, the foregut of herbivorous ruminant animals such as cattle, functions as a bioreactor to process complex plant material. Among the numerous and diverse microbes involved in ruminal digestion are the ruminal protozoans, which are single-celled, ciliated eukaryotic organisms. An activity-based screen was executed to identify genes encoding fibrolytic enzymes present in the metatranscriptome of a bovine ruminal protozoan-enriched cDNA expression library. Of the four novel genes identified, two were characterized in biochemical assays. Our results provide evidence for the effective use of functional metagenomics to retrieve novel enzymes from microbial populations that cannot be maintained in axenic cultures. [ABSTRACT FROM AUTHOR]

Aging is associated with insulin resistance, often attributable to obesity and inactivity. Recent evidence suggests that skeletal muscle insulin resistance in aging is associated with mitochondrial alterations. Whether this is true of the senescent myocardium is unknown. Twelve young (Y, 4 years old) and 12 old (O, 11 years old) dogs, matched for body mass, were instrumented with left-ventricular pressure gauges, aortic and coronary sinus catheters, and flow probes on left circumflex artery. Before surgery, all dogs participated in a 6-wk exercise program. Dogs underwent measurements of hemodynamics and plasma substrates before and during a 2-h hyperinsulinemic-euglycemic clamp to measure whole body and myocardial glucose and nonesterified fatty acid uptake. Following the protocol, myocardial and skeletal samples were obtained to measure components of the insulin-signaling cascade and mitochondrial structure. There was no difference in plasma glucose (Y, 90 ± 4 mg/dl; O, 87 ± 4 mg/dl), but old dogs had higher (P < 0.02) nonesterified fatty acids (Y, 384 ± 48 μmol/1; O, 952 ± 97 μmol/1) and plasma insulin (Y, 39 ± 11 μmol/1; O, 108 ± 18 μmol/1). Old dogs had impaired total body glucose disposition (Y, 11.5 ± 1 mg·kg-1·min-1; O, 8.0 ± 0.5 mg·kg-1·min-1; P < 0.05) and insulin-stimulated myocardial glucose uptake (Y, 3.5 ± 0.3mg·min-1·g-1; O, 1.8 ± 0.3 mg·min-1·g-1 P < 0.05). The impaired insulin action was associated with altered insulin signaling and glucose transporter (GLUT4) translocation. There were myocardial mitochondrial structural changes observed in association with decreased expression of uncoupling protein-3. Aging is associated with both whole body and myocardial insulin resistance, independent of obesity and inactivity, but involving altered mitochondrial structure and impaired cellular insulin action. [ABSTRACT FROM AUTHOR]