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21.
Oral fluid is of increasing interest as an alternative sample matrix in drugs of abuse analysis. Compared to the conventional sample matrix blood, sample volumes of oral fluid are smaller and the concentrations of some drugs can be much lower. This imposes some restrictions on the analysis method, which has to be able to detect and quantify multiple analytes from a small sample volume at low concentrations. A sensitive multi-component method for quantitative determination of 50 drug compounds from oral fluid samples collected with the StatSure SalivaSampler? device was developed. The compounds analysed include cannabis, cocaine, amphetamines, opioids, benzodiazepines and other psychoactive medicines. Both liquid–liquid-extraction (LLE) and solid-phase-extraction (SPE) are employed in the sample pre-treatment and the samples are analysed using gas chromatography–mass spectrometry (GC–MS) with the mass selective detector (MSD) operating in either electron ionization (EI) or negative-ion chemical ionization (NICI) mode. The method was fully validated, and the validated parameters included linearity, selectivity, accuracy, precision, and extraction efficiency. Stability of the collected samples during storage at ?18 °C was also studied, and even after over a year's storage all analyte concentrations were more than 60% of the original concentrations. The described method is suitable for routine analysis of oral fluid samples and it has been applied to analysis of more than 4000 oral fluid samples collected anonymously from volunteer road users in Finland during 2007–2009 as a part of the EU project DRUID (Driving under the Influence of Drugs, Alcohol and Medicines). At the moment the developed method is the most comprehensive validated analysis method for oral fluid samples.  相似文献   
22.
Gerbera hybrida is a member of the large sunflower family (Asteraceae). Typical of Asteraceae, Gerbera bears different types of flowers in its inflorescence. The showy marginal flowers comprise elongate, ligulate corollas that are female, whereas the central and inconspicuous disc flowers are complete, with both male and female organs. As such, Gerbera offers great potential for comparative developmental research within a single genotype. Moreover, different Gerbera varieties show an impressive spectrum of color patterns, directly displaying responses to developmental cues at all important morphological levels (flower type, flower organ and within organs). Further, Gerbera harbors an arsenal of Asteraceae-type secondary metabolites, not present in other model plants. With powerful reverse genetics methods, a large collection of EST sequences and a new cDNA microarray, Gerbera has become a model plant of the sunflower family.  相似文献   
23.

Background

Atherosclerosis is a complex disease with hundreds of genes influencing its progression. In addition, the phenotype of the disease varies significantly depending on the arterial bed.

Methodology/Principal Findings

We characterized the genes generally involved in human advanced atherosclerotic (AHA type V–VI) plaques in carotid and femoral arteries as well as aortas from 24 subjects of Tampere Vascular study and compared the results to non-atherosclerotic internal thoracic arteries (n=6) using genome-wide expression array and QRT-PCR. In addition we determined genes that were typical for each arterial plaque studied. To gain a comprehensive insight into the pathologic processes in the plaques we also analyzed pathways and gene sets dysregulated in this disease using gene set enrichment analysis (GSEA). According to the selection criteria used (>3.0 fold change and p-value <0.05), 235 genes were up-regulated and 68 genes down-regulated in the carotid plaques, 242 genes up-regulated and 116 down-regulated in the femoral plaques and 256 genes up-regulated and 49 genes down-regulated in the aortic plaques. Nine genes were found to be specifically induced predominantly in aortic plaques, e.g., lactoferrin, and three genes in femoral plaques, e.g., chondroadherin, whereas no gene was found to be specific for carotid plaques. In pathway analysis, a total of 28 pathways or gene sets were found to be significantly dysregulated in atherosclerotic plaques (false discovery rate [FDR] <0.25).

Conclusions

This study describes comprehensively the gene expression changes that generally prevail in human atherosclerotic plaques. In addition, site specific genes induced only in femoral or aortic plaques were found, reflecting that atherosclerotic process has unique features in different vascular beds.  相似文献   
24.
BackgroundThe aim of the study was to evaluate differences in the loading of glenohumeral joint muscles between a cable pulley machine (CP) and variable resistance machine (VR) during axial humeral external rotation.MethodsEleven healthy male subjects took part in the study. Intramuscular electromyography from five muscles of the shoulder (medial deltoid, supraspinatus, infraspinatus and upper part of the trapezius), torque and power output was measured at different rotation angles and with different loads (10%, 50% and 100% of 1RM). Also the compressive and shear force in the glenohumeral joint was analyzed at the horizontal level at angles of rotation. External rotation was performed with a self-selected velocity on the scapular plane.FindingsIn the CP the range of movement became narrower than in the VR with increasing workload (P < 0.05). The activity of the infraspinatus did not grow in the CP after 50% load, while it did in the VR (P < 0.01). The upper part of the trapezius was activated less in the CP than in the VR (P < 0.01) machine when using 50% and 100% loads. In comparison with the CP, the shear forces that pull the head of the humerus in a posterior direction were more evenly distributed in the VR than in the CP at different angles of rotation (P < 0.001).InterpretationThe VR seems to make a broader range of motion possible, lager activation the primary external rotators and evenly distributed shear forces than the CP. However, performing the exercise with VR and high load also activates the upper part of the trapezius.RelevanceThese findings can be used in the development of exercise designs, methods and equipment for shoulder injury rehabilitation.  相似文献   
25.

Background

More accurate coronary heart disease (CHD) prediction, specifically in middle-aged men, is needed to reduce the burden of disease more effectively. We hypothesised that a multilocus genetic risk score could refine CHD prediction beyond classic risk scores and obtain more precise risk estimates using a prospective cohort design.

Methods

Using data from nine prospective European cohorts, including 26,221 men, we selected in a case-cohort setting 4,818 healthy men at baseline, and used Cox proportional hazards models to examine associations between CHD and risk scores based on genetic variants representing 13 genomic regions. Over follow-up (range: 5–18 years), 1,736 incident CHD events occurred. Genetic risk scores were validated in men with at least 10 years of follow-up (632 cases, 1361 non-cases). Genetic risk score 1 (GRS1) combined 11 SNPs and two haplotypes, with effect estimates from previous genome-wide association studies. GRS2 combined 11 SNPs plus 4 SNPs from the haplotypes with coefficients estimated from these prospective cohorts using 10-fold cross-validation. Scores were added to a model adjusted for classic risk factors comprising the Framingham risk score and 10-year risks were derived.

Results

Both scores improved net reclassification (NRI) over the Framingham score (7.5%, p = 0.017 for GRS1, 6.5%, p = 0.044 for GRS2) but GRS2 also improved discrimination (c-index improvement 1.11%, p = 0.048). Subgroup analysis on men aged 50–59 (436 cases, 603 non-cases) improved net reclassification for GRS1 (13.8%) and GRS2 (12.5%). Net reclassification improvement remained significant for both scores when family history of CHD was added to the baseline model for this male subgroup improving prediction of early onset CHD events.

Conclusions

Genetic risk scores add precision to risk estimates for CHD and improve prediction beyond classic risk factors, particularly for middle aged men.  相似文献   
26.
27.
No studies on the concentration dependency of the inhibition of Streptococcus mutans with xylitol are available. We studied xylitol-induced growth inhibition of two type strains, S. mutans NCTC 10449 and Ingbritt, and three clinical isolates of S. mutans. The strains were grown in Brain Hearth Infusion Medium in the presence of 0.001% (0.066 mM), 0.005% (0.33 mM), 0.01% (0.66 mM), 0.1% (6.6 mM), and 1% (66 mM) xylitol. Growth was followed by measuring the absorbance at a wavelength of 660 nm. The highest xylitol concentration tested in this study, 1%, showed mean inhibition percentages ranging from 61% to 76% when the growth inhibition of the five strains was compared to the control without xylitol at log-phase. For 0.1% xylitol, the inhibition percentages ranged from 22% to 59%. A concentration dependency was seen in the growth inhibition, with 0.01% xylitol being the lowest xylitol concentration inhibiting all five strains significantly (p < 0.001). The growth inhibition percentages determined for 0.01% xylitol, however, were low, and the inhibition was significantly weaker as compared to 0.1% and 1% xylitol. Our results suggest that low xylitol concentrations of 0.1% (6.6 mM) could inhibit mutans streptococci in vivo but even lower xylitol concentrations may be inhibitory.  相似文献   
28.
The marsh fritillary butterfly Euphydryas aurinia is an endangered species in most of northern Europe. We describe the metapopulation structure of E. aurinia in Finland, where the species has declined drastically in the past decades. We found two types of habitat patches suitable for the species: semi-permanent meadows and transient clearcuts in the forest. Patch area was the most significant variable predicting the occurrence of E. aurinia in a habitat patch. The species tended to be found in young rather than old clearcuts, apparently because the vegetation became too high in the latter. We used the incidence function model to simulate the metapopulation dynamics of E. aurinia in its dynamic landscape and discovered that the continued presence of the semi-permanent meadows is essential for the survival of the species in the study area in southeast Finland.  相似文献   
29.
30.
Two high-resolution pollen and charcoal analyses were constructed from sediments obtained from a small bay in eastern Finland in order to gain information on human activity during the Neolithic Stone Age, 5200–1800 bc. We used measurements of loss on ignition (LOI), magnetic susceptibility and geochemical analyses to describe the sedimentological characteristics. Palaeomagnetic dating and measurements of 137Cs-activity were supported by 14C-datings. The analyses revealed human activity between 4400 and 3200 bc, which is synchronous with archaeological cultures defined through different stages of Comb Ware pottery types and Middle Neolithic pottery types with asbestos as a primary temper. Direct evidence of Hordeum cultivation was dated to 4040–3930 cal bc. According to the pollen data, more significant effort was put into the production of fibres from hemp and lime than the actual cultivation of food.  相似文献   
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