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Numerous health benefits are attributed to the n-3 long-chain PUFA (n-3 LCPUFA); EPA and DHA. A systematic literature review was conducted to investigate factors, other than diet, that are associated with the n-3 LCPUFA levels. The inclusion criteria were papers written in English, carried out in adult non-pregnant humans, n-3 LCPUFA measured in blood or tissue, data from cross-sectional studies, or baseline data from intervention studies. The search revealed 5076 unique articles of which seventy were included in the qualitative synthesis. Three main groups of factors potentially associated with n-3 LCPUFA levels were identified: (1) unmodifiable factors (sex, genetics, age), (2) modifiable factors (body size, physical activity, alcohol, smoking) and (3) bioavailability factors (chemically bound form of supplements, krill oil v. fish oil, and conversion of plant-derived α-linolenic acid (ALA) to n-3 LCPUFA). Results showed that factors positively associated with n-3 LCPUFA levels were age, female sex (women younger than 50 years), wine consumption and the TAG form. Factors negatively associated with n-3 LCPUFA levels were genetics, BMI (if erythrocyte EPA and DHA levels are <5·6 %) and smoking. The evidence for girth, physical activity and krill oil v. fish oil associated with n-3 LCPUFA levels is inconclusive. There is also evidence that higher ALA consumption leads to increased levels of EPA but not DHA. In conclusion, sex, age, BMI, alcohol consumption, smoking and the form of n-3 LCPUFA are all factors that need to be taken into account in n-3 LCPUFA research.
To assess the societal cost-effectiveness of the Transmural Trauma Care Model (TTCM), a multidisciplinary transmural rehabilitation model for trauma patients, compared with regular care.
The economic evaluation was performed alongside a before-and-after study, with a convenience control group measured only afterward, and a 9-month follow-up. Control group patients received regular care and were measured before implementation of the TTCM. Intervention group patients received the TTCM and were measured after its implementation. The primary outcome was generic health-related quality of life (HR-QOL). Secondary outcomes included disease-specific HR-QOL, pain, functional status, and perceived recovery.
Eighty-three trauma patients were included in the intervention group and fifty-seven in the control group. Total societal costs were lower in the intervention group than in the control group, but not statistically significantly so (EUR-267; 95 percent confidence interval [CI], EUR-4,175–3011). At 9 months, there was no statistically significant between-group differences in generic HR-QOL (0.05;95 percent CI, −0.02–0.12) and perceived recovery (0.09;95 percent CI, −0.09–0.28). However, mean between-group differences were statistically significantly in favor of the intervention group for disease-specific HR-QOL (−8.2;95 percent CI, −15.0–−1.4), pain (−0.84;95CI, −1.42–−0.26), and functional status (−20.1;95 percent CI, −29.6–−10.7). Cost-effectiveness acceptability curves indicated that if decision makers are not willing to pay anything per unit of effect gained, the TTCM has a 0.54–0.58 probability of being cost-effective compared with regular care. For all outcomes, this probability increased with increasing values of willingness-to-pay.
The TTCM may be cost-effective compared with regular care, depending on the decision-makers willingness to pay and the probability of cost-effectiveness that they perceive as acceptable.
Randomised studies examining the effect on patients of training
professionals in adherence to suicide guidelines are scarce.
To assess whether patients benefited from the training of professionals
in adherence to suicide guidelines.
In total 45 psychiatric departments were randomised (Dutch trial
register: NTR3092). In the intervention condition, all staff in the
departments were trained with an e-learning supported train-the-trainer
programme. After the intervention, patients were assessed at admission
and at 3-month follow-up. Primary outcome was change in suicide ideation,
assessed with the Beck Scale for Suicide Ideation.
For the total group of 566 patients with a positive score on the Beck
Scale for Suicide Ideation at baseline, intention-to-treat analysis
showed no effects of the intervention on patient outcomes at 3-month
follow-up. Patients who were suicidal with a DSM-IV diagnosis of
depression (n = 154) showed a significant decrease in
suicide ideation when treated in the intervention group. Patients in the
intervention group more often reported that suicidality was discussed
Overall, no effect of our intervention on patients was found. However, we
did find a beneficial effect of the training of professionals on patients
Vitamin D is a fat-soluble hormone that traditionally has been linked to bone health. Recently, its involvement has been extended to other (extra-skeletal) disease areas, such as cancer, CVD, energy metabolism and autoimmune diseases. Vitamin D deficiency is a worldwide problem, and several recommendation-setting bodies have published guidelines for adequate vitamin D intake and status. However, recommendations from, for example, the Health Council of the Netherlands do not provide advice on how to treat vitamin D deficiency, a condition that is often encountered in the clinic. In addition, these recommendations provide guidelines for the maintenance of ‘minimum levels’, and do not advise on ‘optimum levels’ of vitamin D intake/status to further improve health. The NutriProfiel project, a collaboration between the Gelderse Vallei Hospital (Ede, the Netherlands) and the Division of Human Nutrition of Wageningen University (Wageningen, the Netherlands), was initiated to formulate a protocol for the treatment of vitamin deficiency and for the maintenance of optimal vitamin D status. To discuss the controversies around treatment of deficiency and optimal vitamin D status and intakes, a workshop meeting was organised with clinicians, scientists and dietitians. In addition, a literature review was conducted to collect recent information on optimal intake of vitamins, their optimal circulating concentrations, and effective dosing regimens to treat deficiency. This information has been translated into the NutriProfiel advice, which is outlined in this article.
Several studies have shown that South Asian neonates have a characteristic thin–fat insulin-resistant phenotype. The aim of our study was to determine whether this phenotype is also present in South Asians who have migrated to a Western country (the Netherlands). South Asian and white Dutch pregnant women were included in our study. After delivery, cord blood was collected and neonatal anthropometry was measured within 72 h. Compared with white Dutch mothers, South Asian mothers were younger (28.5 v. 32.2 years, P<0.001) and had a higher prepregnancy body mass index (25.1 v. 23.0, P=0.001). Gestational age at delivery was on average 4 days shorter in South Asians (274.9 v. 278.8, P=0.001). To compare the two groups of neonates, we calculated sex- and gestation-specific s.d. scores using the values for mean and s.d. obtained from the white Dutch subjects as a reference. All measurements were smaller in South Asian neonates, except for those of the skinfolds. The largest difference was found in abdominal circumference (s.d. score 1.39, 95% CI −1.76 to −1.01). Triceps and subscapular skinfolds were similar in both groups (triceps s.d. score −0.34, 95% CI −0.88 to +0.20 and subscapular s.d. score −0.03, 95% CI −0.31 to +0.25). South Asian neonates had higher cord plasma levels of triglycerides (0.40 v. 0.36, P=0.614), glucose (5.4 v. 4.8, P=0.079) and insulin (6.3 v. 4.0, P=0.051). However, these differences were not statistically significant. After adjustment for birth weight, the difference in insulin became statistically significant (P=0.001). We therefore conclude that the thin–fat insulin-resistant phenotype is also present in South Asian neonates in the Netherlands.
A combination of high folate with low vitamin B12 plasma status has been associated with cognitive impairment in a population exposed to mandatory folic acid fortification. The objective of the present study was to examine the interactions between plasma concentrations of folate and vitamin B12 markers in relation to cognitive performance in Norwegian elderly who were unexposed to mandatory or voluntary folic acid fortification. Cognitive performance was assessed by six cognitive tests in 2203 individuals aged 72–74 years. A combined score was calculated using principal component analysis. The associations of folate concentrations, vitamin B12 markers (total vitamin B12, holotranscobalamin (holoTC) and methylmalonic acid (MMA)) and their interactions in relation to cognitive performance were evaluated by quantile regression and least-squares regression, adjusted for sex, education, apo-ɛ4 genotype, history of CVD/hypertension and creatinine. Cross-sectional analyses revealed an interaction (P= 0·009) between plasma concentrations of folate and vitamin B12 in relation to cognitive performance. Plasma vitamin B12 concentrations in the lowest quartile ( < 274 pmol/l) combined with plasma folate concentrations in the highest quartile (>18·5 nmol/l) were associated with a reduced risk of cognitive impairment compared with plasma concentrations in the middle quartiles of both vitamins (OR 0·22, 95 % CI 0·05, 0·92). The interaction between folate and holoTC or MMA in relation to cognitive performance was not significant. In conclusion, this large study population unexposed to mandatory folic acid fortification showed that plasma folate, but not plasma vitamin B12, was associated with cognitive performance. Among the elderly participants with vitamin B12 concentrations in the lower range, the association between plasma folate and cognitive performance was strongest.
An established population of the exotic woodwasp Sirex noctilio Fabricius (Hymenoptera: Siricidae) was first detected in North America in 2004. In order to develop survey guidelines for the detection of this major pest of Pinus Linnaeus species in the Southern Hemisphere, we examined 231 Pinus sylvestris biweekly to establish the timing and spatial distribution of resinosis symptoms of attack, and the timing of subsequent tree mortality. Fresh resin appeared between mid-July and late August, and on 70% of infested trees was observed on the mid bole. The occurrence of tree death varied between sites, from 2 weeks after the first detection of resinosis in one site to several months in seven other sites. Findings from our study provide key information to improve detection of S. noctilio and predict its impact on forest stands in its new range in northeastern North America.
This study aimed to identify the incidence of residual viable neck disease in patients with mucosal squamous cell carcinoma of the upper aero-digestive tract, following primary chemoradiation at a tertiary centre.
Retrospective chart review of patients treated with primary chemoradiation for squamous cell carcinoma of the aero-digestive tract between August 2001 and August 2008. Neck status pre- and post-treatment was the primary focus.
Forty-two patients with node-positive disease prior to chemoradiation were included. Thirty-seven (88.1 per cent) achieved complete response to treatment: no patient in this group underwent neck dissection, five died due to recurrence at the primary site or distant metastasis, and none suffered neck recurrence. Five (11.9 per cent) patients achieved partial response to chemoradiation and underwent neck dissection; viable tumour was found in one patient.
Our data support conservative management of the neck in patients with complete response to chemoradiation, and consolidation neck dissection in patients with partial response.
The metal-catalyst-free growth of carbon nanotubes (CNTs) using chemical vapor deposition and the application in field-effect transistors (FETs) is presented. The CNT growth process used a 3-nm-thick Ge layer on SiO2 that was subsequently annealed to produce Ge nanoparticles. Raman measurements show the presence of radial breathing mode (RBM) peaks and the absence of the disorder induced D-band, indicating single walled CNTs (SWNTs) with a low defect density. The synthesized CNTs are used to fabricate CNTFETs and the best device has a state-of-the-art on/off current ratio of 3×108 and a steep sub-threshold slope of 110 mV/decade.
What is called in this chapter the “engineering” of natural photosynthesis has been performed by evolution over several billions of years. Its optimization, against thermodynamic and other selection criteria from the biological environment, has led to a remarkably limited set of molecular and supramolecular motifs. Photosynthesis starts with absorption of light by mutually interacting chlorophyll (Chl) and related molecules. These are embedded in protein matrices that promote rapid transport of energy by excitons and lower the energy of transition states for charge separation and multielectron catalysis. An understanding of engineered natural photosynthesis is the underpinning of the design of artificial solar-to-fuel devices.
Light energy is abundant and evenly spread over the surface of the Earth, and virtually all organisms depend on the conversion and chemical storage of light energy by natural photosynthesis. The advent of natural photosynthesis opened up new energy conversion pathways for progression toward thermodynamic equilibrium between the very hot Sun and the much colder Earth. The first-principles thermodynamic and mechanistic analysis of how natural photosynthesis is engineered by biological evolution in this chapter shows that combining different functionalities of light harvesting, charge separation, and catalysis in small molecules or at a single narrow interface is incompatible with high solar-to-fuel conversion efficiency, and that possible solutions to the problem of accumulation of solar energy in chemicals require complex device topologies. This led biology to a modular design approach that is the basis of photosynthesis. It is the result of an intensive evolutionary effort of shaping complex structures, driven by the abundant solar energy spread over the planet.
Long-term supplementation with folic acid may improve cognitive performance in older individuals. The relationship between folate status and cognitive performance might be mediated by changes in methylation capacity, as methylation reactions are important for normal functioning of the brain. Although aberrant DNA methylation has been implicated in neurodevelopmental disorders, the relationship between DNA methylation status and non-pathological cognitive functioning in human subjects has not yet been investigated. The present study investigated the associations between global DNA methylation and key domains of cognitive functioning in healthy older adults. Global DNA methylation, defined as the percentage of methylated cytosine to total cytosine, was measured in leucocytes by liquid chromatography–MS/MS, in 215 men and women, aged 50–70 years, who participated in the Folic Acid and Carotid Intima-Media Thickness (FACIT) study (clinical trial registration number NCT00110604). Cognitive performance was assessed by means of the Visual Verbal Word Learning Task, the Stroop Colour-Word Interference Test, the Concept Shifting Test, the Letter–Digit Substitution Test and the Verbal Fluency Test. Using hierarchical linear regression analyses adjusted for age, sex, level of education, alcohol consumption, smoking status, physical activity, erythrocyte folate concentration and 5,10-methylenetetrahydrofolate reductase 677 C → T genotype, we found that global DNA methylation was not related to cognitive performance on any of the domains measured. The present study results do not support the hypothesis that global DNA methylation, as measured in leucocytes, might be associated with cognitive functioning in healthy older individuals.
The Rank Forum on Vitamin D was held on 2nd and 3rd July 2009 at the University of Surrey, Guildford, UK. The workshop consisted of a series of scene-setting presentations to address the current issues and challenges concerning vitamin D and health, and included an open discussion focusing on the identification of the concentrations of serum 25-hydroxyvitamin D (25(OH)D) (a marker of vitamin D status) that may be regarded as optimal, and the implications this process may have in the setting of future dietary reference values for vitamin D in the UK. The Forum was in agreement with the fact that it is desirable for all of the population to have a serum 25(OH)D concentration above 25 nmol/l, but it discussed some uncertainty about the strength of evidence for the need to aim for substantially higher concentrations (25(OH)D concentrations>75 nmol/l). Any discussion of ‘optimal’ concentration of serum 25(OH)D needs to define ‘optimal’ with care since it is important to consider the normal distribution of requirements and the vitamin D needs for a wide range of outcomes. Current UK reference values concentrate on the requirements of particular subgroups of the population; this differs from the approaches used in other European countries where a wider range of age groups tend to be covered. With the re-emergence of rickets and the public health burden of low vitamin D status being already apparent, there is a need for urgent action from policy makers and risk managers. The Forum highlighted concerns regarding the failure of implementation of existing strategies in the UK for achieving current vitamin D recommendations.
International trade flows have increased impressively in the last few decades. Data from the United Nations, which have been edited by Feenstra et al. (2005), suggest that the aggregate nominal value of reported international trade increased from about US$130 billion in 1962 to more than US$6.5 trillion in 2000. This corresponds to an annual growth rate close to 11 per cent. With an estimated world population of about 6 billion in 2000, this implies that international trade per capita was over US$1,000 or about 15 per cent of the average Gross Domestic Product (GDP) per capita.
The growing importance of international trade has led to an increased need for sound analyses of its determinants. The gravity model has been the workhorse model to explain international trade flows for nearly half a century now. The main idea behind this model is that the magnitude of bilateral trade flows can be explained by the economic size of the two trading countries and the distance between them (Deardorff 1998). The model has sound theoretical foundations, yields almost invariantly plausible parameter estimates, and has a strong explanatory power.
Although the basic framework of the gravity model is unaltered throughout the years, new insights have contributed to its increasing popularity by improving its theoretical underpinnings (see, e.g. Feenstra 2004) and addressing econometric issues concerning the correct specification of the model (see, e.g., Anderson and van Wincoop 2004).
To reduce the level of redundancy in a collection of cultivated lettuce, data from 160 amplified fragment length polymorphism (AFLP) fragments and 10 polymorphic microsatellites were used in combination with passport data and morphological data, the latter obtained from an experimental field trial performed for verification purposes. Based on the observed distribution of the number of marker differences between and within accessions, a minimum of three AFLP differences and two microsatellite differences were regarded as levels warranting distinction between accessions in the redundancy analysis. The strategy followed in the redundancy analysis was mainly based on the confirmation of duplication by each of two independently generated data sources. The molecular data were used for the validation as well as the identification of potential duplicates, revealing a total number of 198 redundancies, corresponding to 12.9% of the total collection. Trueness to type, number of characterization and evaluation data, and collection management considerations, such as available seed quantities and germination percentages, were used as primary, secondary and tertiary criteria to decide which accession from duplication groups to maintain in the collection. Removal of accessions showed negligible effects on total collection diversity, as quantified for AFLPs and microsatellites, characterization and evaluation traits and resistance profiles against downy mildew pathotypes, indicating that the applied strategy was effective.
Stool samples from Belgian patients suffering from abdominal pain and/or diarrhoea were examined for Cryptosporidium and Giardia. Cryptosporidium-positive samples were genotyped using the 70 kDa heat shock protein and the 60 kDa glycoprotein (GP60) genes: C. hominis was identified in 54·2% and C. parvum in 45·8% of the samples. Sequencing at the GP60 locus indicated that subgenotype IbA10G2 of C. hominis and subgenotype IIaA15G2R1 of C. parvum were the most prevalent, although several other subgenotypes were identified. For Giardia, sequencing at the β-giardin, triose phosphate isomerase (TPI) and glutamate dehydrogenase (GDH) genes revealed assemblage B as the most prevalent (74·4%) in human patients. A high degree of heterogeneity was found, especially on the β-giardin gene, and to a lesser extent on the GDH gene. Furthermore, using a novel species-specific PCR based on the TPI gene, mixed infections with both assemblage A and B were detected in a large number (32·4%) of human patients, which might have important epidemiological implications.
Limited information is available with respect to the association between age and the plasma phospholipid fatty acid profile. Therefore we investigated the association between plasma phospholipid fatty acid status and age after correction for sex, smoking, alcohol use, BMI and fish intake. Plasma phospholipid fatty acid composition was measured and information on fish intake and other potential covariates was collected in 234 participants of the Maastricht Aging Study. The participants were healthy individuals of both sexes with an age range between 36 and 88 years. Hierarchical linear regression analyses were applied to study the relationship between age and fatty acid concentrations. After correction for fish consumption and other relevant covariates, a significant positive relationship was observed between age of the subjects and their plasma phospholipid concentrations of DHA (22 : 6n-3, P = 0·006) and EPA (20 : 5n-3; P = 0·001). Age contributed 2·3 and 3·9 % to the amount of explained variance, respectively. The higher n-3 long-chain PUFA status at advanced age was confirmed by lower concentrations of their putative ‘shortage marker’ Osbond acid (ObA, 22 : 5n-6; P = 0·022 for the relationship with age after correction for covariates and fish intake, R2 0·022). Concentrations of linoleic acid (LA; 18 : 2n-6) were negatively associated with age (P < 0·001; R2 0·061). In conclusion, DHA and EPA concentrations appeared to be higher in older age groups, partly because of a higher fish intake and partly because of another age-associated mechanism, possibly involving the well-known competition with LA.
Gold inverse spherical nanoscale voids have been fabricated in linear arrays for directional plasmon measurements in the visible spectral range. We show that by KOH anisotropic etching in Si, we are able to make V-grooves in which latex spheres of the order of 500 nm self-assemble with largely defect-free cubic symmetry. Both single layer and multilayer assembly in a face-centered close-packed (FCC) lattice can be achieved by varying the width of the trenches. This template is subsequently used for electrodeposition of gold to create the inverse spherical nanovoids.
The importance of the one-carbon metabolites, choline and homocysteine, to brain function is well known. However, the associations between the one-carbon metabolites choline, betaine, methionine and dimethylglycine with cognition in elderly are unclear. We therefore examined the associations of these metabolites with cognition in a double-blind, placebo-controlled trial. Individuals (n 195) were randomized to receive daily oral capsules with either 1000 μg cobalamin (vitamin B12), or 1000 μg cobalamin plus 400 μg folic acid, or placebo for 24 weeks. Concentrations of homocysteine, methionine, choline, betaine and dimethylglycine were assessed before and after 12 and 24 weeks of treatment. Cognitive function, including domains of attention, construction, sensomotor speed, memory and executive function, was assessed before and after 24 weeks of treatment. At baseline, elevated plasma homocysteine was associated with lower performance of attention, construction, sensomotor speed and executive function. In addition, betaine was positively associated with better performance of construction, sensomotor speed and executive function, whereas elevated concentrations of methionine were positively associated with sensomotor speed. Daily combined supplementation with cobalamin plus folic acid decreased total homocysteine concentrations by 36 %, and increased betaine concentrations by 38 %. Participants with the largest increases in betaine concentrations showed a borderline significant (P = 0·07) higher memory performance compared to those without it. Although this trial observed associations of homocysteine and betaine with cognitive domains prior to supplementation, decreased concentrations of homocysteine were not related to improved cognitive performance. There was a tendency of participants with the largest increases in betaine concentrations to show the greatest improvement in memory function.