454 research outputs found
Effect of dietary fat supplementation during late pregnancy and first six months of lactation on maternal and infant vitamin A status in rural Bangladesh
Dietary fat intake is extremely low in most communities with vitamin A
deficiency. However, its role in vitamin A status of pregnant and
lactating women is poorly understood. The aim of the study was to
examine the effect of supplementing women with fat from mid-/late
pregnancy until six months postpartum on their vitamin A status and
that of their infants. Women recruited at 5-7 months of gestation were
supple-mented daily with 20 mL of soybean-oil (n=248) until six months
postpartum or received no supplement (n=251). Dietary fat intake was
assessed by 24-hour dietary recall at enrollment and at 1, 3 and 6
months postpartum. Concentrations of maternal plasma retinol,
\u3b2-carotene, and lutein were measured at enroll-ment and at 1, 3
and 6 months postpartum, and those of infants at six months postpartum.
Concentration of breastmilk retinol was measured at 1, 3 and 6 months
postpartum. The change in concentration of plasma retinol at three
months postpartum compared to pregnancy was significantly higher in the
supple-mented compared to the control women (+0.04 vs -0.07 \u3bcmol/L
respectively; p<0.05). Concentrations of plasma \u3b2-carotene and
lutein declined in both the groups during the postpartum period but the
decline was significantly less in the supplemented than in the control
women at one month \u3b2-carotene -0.07 vs -0.13 \u3bcmol/L,
p<0.05); lutein -0.26 vs -0.49 \u3bcmol/L, p<0.05) and three
months \u3b2-carotene -0.04 vs -0.08 \u3bcmol/L, p<0.05; lutein
-0.31 vs -0.47 \u3bcmol/L, p<0.05). Concentration of breastmilk
retinol was also signifi-cantly greater in the supplemented group at
three months postpartum than in the controls (0.68\ub10.35 vs
0.55\ub10.34 \u3bcmol/L respectively, p<0.03). Concentrations of
infants\u2032 plasma retinol, \u3b2-carotene, and lutein, measured at
six months of age, did not differ between the groups. Fat
supplementation during pregnancy and lactation in women with a very low
intake of dietary fat has beneficial effects on maternal postpartum
vitamin A status
The correlation between posterior tibial slope and dynamic anterior tibial translation and dynamic range of tibial rotation
PURPOSE: The amount of passive anterior tibial translation (ATT) is known to be correlated to the amount of posterior tibial slope (PTS) in both anterior cruciate ligament-deficient and reconstructed knees. Slope-altering osteotomies are advised when graft failure after anterior cruciate ligament (ACL) reconstruction occurs in the presence of high PTS. This recommendation is based on studies neglecting the influence of muscle activation. On the other hand, if dynamic range of tibial rotation (rTR) is related to the amount of PTS, a âsimpleâ anterior closing-wedge osteotomy might not be sufficient to control for tibial rotation. The purpose of this study was to evaluate the correlation between the amount of PTS and dynamic ATT and tibial rotation during high demanding activities, both before and after ACL reconstruction. We hypothesized that both ATT and rTR are strongly correlated to the amount of PTS. METHODS: Ten subjects were studied both within three months after ACL injury and one year after ACL reconstruction. Dynamic ATT and dynamic rTR were measured using a motion-capture system during level walking, during a single-leg hop for distance and during a side jump. Both medial and lateral PTS were measured on MRI. A difference between medial and lateral PTS was calculated and referred to as Î PTS. Spearmanâs correlation coefficients were calculated for the correlation between medial PTS, lateral PTS and Î PTS and ATT and between medial PTS, lateral PTS and Î PTS and rTR. RESULTS: Little (if any) to weak correlations were found between medial, lateral and Î PTS and dynamic ATT both before and after ACL reconstruction. On the other hand, a moderate-to-strong correlation was found between medial PTS, lateral PTS and Î PTS and dynamic rTR one year after ACL reconstruction. CONCLUSION: During high-demand tasks, dynamic ATT is not correlated to PTS. A compensation mechanism may be responsible for the difference between passive and dynamic ATT in terms of the correlation to PTS. A moderate-to-strong correlation between amount of PTS and rTR indicates that such a compensation mechanism may fall short in correcting for rTR. These findings warrant prudence in the use of a pure anterior closing wedge osteotomy in ACL reconstruction. TRIAL REGISTRATION: Netherlands Trial Register, Trial 7686. Registered 16 April 2016âRetrospectively registered. LEVEL OF EVIDENCE: Level 2, prospective cohort stud
WHO European Childhood Obesity Surveillance Initiative: body mass index and level of overweight among 6-9-year-old children from school year 2007/2008 to school year 2009/2010
Background: The World Health Organization (WHO) Regional Office for Europe has established the Childhood Obesity
Surveillance Initiative (COSI) to monitor changes in overweight in primary-school children. The aims of this paper are to
present the anthropometric results of COSI Round 2 (2009/2010) and to explore changes in body mass index (BMI) and
overweight among children within and across nine countries from school years 2007/2008 to 2009/2010.
Methods: Using cross-sectional nationally representative samples of 6â9-year-olds, BMI, anthropometric Z-scores and
overweight prevalence were derived from measured weight and height. Significant changes between rounds were
assessed using variance and t-tests analyses.
Results: At Round 2, the prevalence of overweight (including obesity; WHO definitions) ranged from 18% to 57%
among boys and from 18% to 50% among girls; 6 â 31% of boys and 5 â 21% of girls were obese. Southern
European countries had the highest overweight prevalence. Between rounds, the absolute change in mean BMI
(range: from â0.4 to +0.3) and BMI-for-age Z-scores (range: from â0.21 to +0.14) varied statistically significantly
across countries. The highest significant decrease in BMI-for-age Z-scores was found in countries with higher absolute
BMI values and the highest significant increase in countries with lower BMI values. The highest significant decrease in
overweight prevalence was observed in Italy, Portugal and Slovenia and the highest significant increase in Latvia and
Norway.
Conclusions: Changes in BMI and prevalence of overweight over a two-year period varied significantly among
European countries. It may be that countries with higher prevalence of overweight in COSI Round 1 have
implemented interventions to try to remedy this situation
Spain's Budget Neglects Research
Letter.-- Carlos Fenollosa et al.Peer Reviewe
Regulation of the zebrafish goosecoid promoter by mesoderm inducing factors and Xwnt1
Goosecoid is a homeobox gene that is expressed as an immediate early response to mesoderm induction by activin. We have investigated the induction of the zebrafish goosecoid promoter by the mesoderm inducing factors activin and basic fibroblast growth factor (bFGF) in dissociated zebrafish blastula cells, as well as by different wnts in intact embryos. Activin induces promoter activity, while bFGF shows a cooperative effect with activin. We have identified two enhancer elements that are functional in the induction of the goosecoid promoter. A distal element confers activin responsiveness to a heterologous promoter in the absence of de novo protein synthesis, whereas a proximal element responds only to a combination of activin and bFGE Deletion experiments show that both elements are important for full induction by activin. Nuclear proteins that bind to these elements are expressed in blastula embryos, and competition experiments show that an octamer site in the activin responsive distal element is specifically bound, suggesting a role for an octamer binding factor in the regulation of goosecoid expression by activin. Experiments in intact embryos reveal that the proximal element contains sequences that respond to Xwnt1, but not to Xwnt5c. Furthermore, we show that the distal element is active in a confined dorsal domain in embryos and responds to overexpression of activin in vivo, as well as to dorsalization by lithium. The distal element is to our knowledge the first enhancer element identified that mediates the induction of a mesodermal gene by activin
Contacts and contracts: Cross-level network dynamics in the development of an aircraft material
In this paper, we investigate how interorganizational networks and interpersonal networks interact over time. We present a retrospective longitudinal case study of the network system that developed a novel aircraft material and analyze changeepisodes from a structurationist perspective. We identify five types of episodes in which interpersonal and interorganizational networks interact (persistence, prospecting, consolidation, reconfiguration, and dissolution) and analyze conditionsfor these episodes and sequences among them. Our findings advance a cross-level perspective on embeddedness and show how individuals may draw on relational and structural embeddedness as distributed resources. The multiple levels of embeddedness impact network dynamics by introducing converging and diverging dialectics, thereby limiting path dependence and proactive network orchestration
Comprehensive routine diagnostic screening to identify predictive mutations, gene amplifications, and microsatellite instability in FFPE tumor material
Background: Sensitive and reliable molecular diagnostics is needed to guide therapeutic decisions for cancer patients. Although less material becomes available for testing, genetic markers are rapidly expanding. Simultaneous detection of predictive markers, including mutations, gene amplifications and MSI, will save valuable material, time and costs. Methods: Using a single-molecule molecular inversion probe (smMIP)-based targeted next-generation sequencing (NGS) approach, we developed an NGS panel allowing detection of predictive mutations in 33 genes, gene amplifications of 13 genes and microsatellite instability (MSI) by the evaluation of 55 microsatellite markers. The panel was designed to target all clinically relevant single and multiple nucleotide mutations in routinely available lung cancer, colorectal cancer, melanoma, and gastro-intestinal stromal tumor samples, but is useful for a broader set of tumor types. Results: The smMIP-based NGS panel was successfully validated and cut-off values were established for reliable gene amplification analysis (i.e. relative coverage â„3) and MSI detection (â„30% unstable loci). After validation, 728 routine diagnostic tumor samples including a broad range of tumor types were sequenced with sufficient sensitivity (2.4% drop-out), including samples with low DNA input (< 10 ng; 88% successful), low tumor purity (5-10%; 77% successful), and cytological material (90% successful). 75% of these tumor samples showed â„1 (likely) pathogenic mutation, including targetable mutations (e.g. EGFR, BRAF, MET, ERBB2, KIT, PDGFRA). Amplifications were observed in 5.5% of the samples, comprising clinically relevant amplifications (e.g. MET, ERBB2, FGFR1). 1.5% of the tumor samples were classified as MSI-high, including both MSI-prone and non-MSI-prone tumors. Conclusions: We developed a comprehensive workflow for predictive analysis of diagnostic tumor samples. The smMIP-based NGS analysis was shown suitable for limited amounts of histological and cytological material. As smMIP technology allows easy adaptation of panels, this approach can comply with the rapidly expanding molecular markers
Lattice models and Landau theory for type II incommensurate crystals
Ground state properties and phonon dispersion curves of a classical linear
chain model describing a crystal with an incommensurate phase are studied. This
model is the DIFFOUR (discrete frustrated phi4) model with an extra
fourth-order term added to it. The incommensurability in these models may arise
if there is frustration between nearest-neighbor and next-nearest-neighbor
interactions. We discuss the effect of the additional term on the phonon
branches and phase diagram of the DIFFOUR model. We find some features not
present in the DIFFOUR model such as the renormalization of the
nearest-neighbor coupling. Furthermore the ratio between the slopes of the soft
phonon mode in the ferroelectric and paraelectric phase can take on values
different from -2. Temperature dependences of the parameters in the model are
different above and below the paraelectric transition, in contrast with the
assumptions made in Landau theory. In the continuum limit this model reduces to
the Landau free energy expansion for type II incommensurate crystals and it can
be seen as the lowest-order generalization of the simplest Lifshitz-point
model. Part of the numerical calculations have been done by an adaption of the
Effective Potential Method, orginally used for models with nearest-neighbor
interaction, to models with also next-nearest-neighbor interactions.Comment: 33 pages, 7 figures, RevTex, submitted to Phys. Rev.
Versatile Coordination of Cyclopentadienyl-Arene Ligands and Its Role in Titanium-Catalyzed Ethylene Trimerization
Cationic titanium(IV) complexes with ansa-(η5-cyclopentadienyl,η6-arene) ligands were synthesized and characterized by X-ray crystallography. The strength of the metal-arene interaction in these systems was studied by variable-temperature NMR spectroscopy. Complexes with a C1 bridge between the cyclopentadienyl and arene moieties feature hemilabile coordination behavior of the ligand and consequently are active ethylene trimerization catalysts. Reaction of the titanium(IV) dimethyl cations with CO results in conversion to the analogous cationic titanium(II) dicarbonyl species. Metal-to-ligand backdonation in these formally low-valent complexes gives rise to a strongly bonded, partially reduced arene moiety. In contrast to the η6-arene coordination mode observed for titanium, the more electron-rich vanadium(V) cations [cyclopentadienyl-arene]V(NiPr2)(NC6H4-4-Me)+ feature η1-arene binding, as determined by a crystallographic study. The three different metal-arene coordination modes that we experimentally observed model intermediates in the cycle for titanium-catalyzed ethylene trimerization. The nature of the metal-arene interaction in these systems was studied by DFT calculations.
First-principles study of the ferroelastic phase transition in CaCl_2
First-principles density-functional calculations within the local-density
approximation and the pseudopotential approach are used to study and
characterize the ferroelastic phase transition in calcium chloride (CaCl_2). In
accord with experiment, the energy map of CaCl_2 has the typical features of a
pseudoproper ferroelastic with an optical instability as ultimate origin of the
phase transition. This unstable optic mode is close to a pure rigid unit mode
of the framework of chlorine atoms and has a negative Gruneisen parameter. The
ab-initio ground state agrees fairly well with the experimental low temperature
structure extrapolated at 0K. The calculated energy map around the ground state
is interpreted as an extrapolated Landau free-energy and is successfully used
to explain some of the observed thermal properties. Higher-order anharmonic
couplings between the strain and the unstable optic mode, proposed in previous
literature as important terms to explain the soft-phonon temperature behavior,
are shown to be irrelevant for this purpose. The LAPW method is shown to
reproduce the plane-wave results in CaCl_2 within the precision of the
calculations, and is used to analyze the relative stability of different phases
in CaCl_2 and the chemically similar compound SrCl_2.Comment: 9 pages, 6 figures, uses RevTeX
- âŠ