771 research outputs found
Maternal obesity is associated with the formation of small dense LDL and hypoadiponectinemia in the third trimester
Context: Maternal obesity is associated with high plasma triglyceride, poor vascular function, and an increased risk for pregnancy complications. In normal-weight pregnant women, higher triglyceride is associated with increased small, dense low-density lipoprotein (LDL).
Hypothesis: In obese pregnancy, increased plasma triglyceride concentrations result in triglyceride enrichment of very low-density lipoprotein-1 particles and formation of small dense LDL via lipoprotein lipase.
Design: Women (n = 55) of body mass index of 18â46 kg/m2 were sampled longitudinally at 12, 26, and 35 weeks' gestation and 4 months postnatally.
Setting: Women were recruited at hospital antenatal appointments, and study visits were in a clinical research suite.
Outcome Measures: Plasma concentrations of lipids, triglyceride-rich lipoproteins, lipoprotein lipase mass, estradiol, steroid hormone binding globulin, insulin, glucose, leptin, and adiponectin were determined.
Results: Obese women commenced pregnancy with higher plasma triglyceride, reached the same maximum, and then returned to higher postnatal levels than normal-weight women. Estradiol response to pregnancy (trimester 1â3 incremental area under the curve) was positively associated with plasma triglyceride response (r2 adjusted 25%, P < .001). In the third trimester, the proportion of small, dense LDL was 2-fold higher in obese women than normal-weight women [mean (SD) 40.7 (18.8) vs 21.9 (10.9)%, P = .014], and 35% of obese, 14% of overweight, and none of the normal-weight women displayed an atherogenic LDL subfraction phenotype. The small, dense LDL mass response to pregnancy was inversely associated with adiponectin response (17%, P = .013).
Conclusions: Maternal obesity is associated with an atherogenic LDL subfraction phenotype and may provide a mechanistic link to poor vascular function and adverse pregnancy outcome
Preeclampsia is associated with compromized maternal synthesis of long chain polyunsaturated fatty acids leading to offspring deficiency
Obesity and excessive lipolysis are implicated in preeclampsia (PE). Intrauterine growth restriction is associated with low maternal body mass index and decreased lipolysis. Our aim was to assess how maternal and offspring fatty acid metabolism is altered in mothers in the third trimester of pregnancy with PE (n=62) or intrauterine growth restriction (n=23) compared with healthy pregnancies (n=164). Markers of lipid metabolism and erythrocyte fatty acid concentrations were measured. Maternal adipose tissue fatty acid composition and mRNA expression of adipose tissue fatty acidâmetabolizing enzymes and placental fatty acid transporters were compared. Mothers with PE had higher plasma triglyceride (21%, P<0.001) and nonesterified fatty acid (50%, P<0.001) concentrations than controls. Concentrations of major nâ6 and nâ3 long-chain polyunsaturated fatty acids in erythrocytes were 23% to 60% lower (all P<0.005) in PE and intrauterine growth restriction mothers and offspring compared with controls. Subcutaneous adipose tissue Îâ5 and Îâ6 desaturase and very long-chain fatty acid elongase mRNA expression was lower in PE than controls (respectively, mean [SD] control 3.38 [2.96] versus PE 1.83 [1.91], P=0.030; 3.33 [2.25] versus 1.03 [0.96], P<0.001; 0.40 [0.81] versus 0.00 [0.00], P=0.038 expression relative to control gene [square root]). Low maternal and fetal long-chain polyunsaturated fatty acid concentrations in PE may be the result of decreased maternal synthesis
Twenty-first century vaccinomics innovation systems: capacity building in the global South and the role of Product Development Partnerships (PDPs)
The availability of sequence information from publicly available complete genomes and data intensive sciences, together with next-generation sequencing technologies offer substantial promise for innovation in vaccinology and global public health in the beginning of the 21st century. This article presents an innovation analysis for the nascent field of vaccinomics by describing one of the major challenges in this endeavor: the need for capacities in âvaccinomics innovation systemsâ to support the developing countries involved in the creation and testing of new vaccines. In particular, we discuss the need for understanding how institutional frameworks can enhance capacities as intrinsic to a systems approach to health technology development. We focus our attention on the global South, meaning the technically less advanced and developing nations in Africa, Asia, and Latin America. This focus is timely and appropriate because the challenge for innovation in postgenomics medicine is markedly much greater in these regions where basic infrastructures are often underresourced and new or the anticipated institutional relationships can be fragile. Importantly, we examine the role of Product Development Partnerships (PDPs) as a 21st century organizational innovation that contributes to strengthening fragile institutions and capacity building. For vaccinomics innovation systems to stand the test of time in a context of global public health, local communities, knowledge, and cultures need to be collectively taken into account at all stages in programs for vaccinomics-guided vaccine development and delivery in the global South where the public health needs for rational vaccine development are urgent
Accuracy of Achenbach Scales in the Screening of ADHD in a Community Mental Health Clinic
Objective To use receiver-operating characteristics analysis to identify multilevel diagnostic likelihood ratios and provide a framework for the diagnosis of attention-deficit/hyperactivity disorder (ADHD) in children (5â10 years old) and adolescents (11â18 years old) in an outpatient setting. Method Caregiver, teacher, and youth reports from the Achenbach System of Empirically Based Assessment (ASEBA) were obtained for 299 children and 321 adolescents with multiple imputation of missing data. The reference standard was diagnosis of ADHD based on case history and a semistructured diagnostic interview masked to the ASEBA measurements. Results In children, caregiver-reported Attention Problems (area under the curve [AUC] = 0.74) outperformed all other subscales of the caregiver and teacher measures (AUCs †0.72). In the older sample, caregiver- and teacher-reported Attention Problems (caregiver AUC = 0.73; teacher AUC = 0.61) were best at identifying ADHD. Inclusion of caregiver and teacher reports significantly (p < .001 for all comparisons) increased prediction of ADHD diagnosis, whereas youth self-report did not. Conclusion Caregiver-reported Attention Problems were more useful than teacher-reports and self-report in identifying ADHD. Combining caregiver and teacher reports improved identification. Multilevel likelihood ratios are provided to facilitate routine clinical use
A lattice model for the kinetics of rupture of fluid bilayer membranes
We have constructed a model for the kinetics of rupture of membranes under
tension, applying physical principles relevant to lipid bilayers held together
by hydrophobic interactions. The membrane is characterized by the bulk
compressibility (for expansion), the thickness of the hydrophobic part of the
bilayer, the hydrophobicity and a parameter characterizing the tail rigidity of
the lipids. The model is a lattice model which incorporates strain relaxation,
and considers the nucleation of pores at constant area, constant temperature,
and constant particle number. The particle number is conserved by allowing
multiple occupancy of the sites. An equilibrium ``phase diagram'' is
constructed as a function of temperature and strain with the total pore surface
and distribution as the order parameters. A first order rupture line is found
with increasing tension, and a continuous increase in proto-pore concentration
with rising temperature till instability. The model explains current results on
saturated and unsaturated PC lipid bilayers and thicker artificial bilayers
made of diblock copolymers. Pore size distributions are presented for various
values of area expansion and temperature, and the fractal dimension of the pore
edge is evaluated.Comment: 15 pages, 8 figure
Exciton Spin Dynamics in Semiconductor Quantum Wells
In this paper we will review Exciton Spin Dynamics in Semiconductor Quantum
Wells. The spin properties of excitons in nanostructures are determined by
their fine structure. We will mainly focus in this review on GaAs and InGaAs
quantum wells which are model systems.Comment: 55 pages, 27 figure
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High Involvement Management, High Performance Work Systems and Well-being
Studies on the impact of high-performance work systems on employees' well-being are emerging but the underlying theory remains weak. This paper attempts to develop theory of the effects on well-being of four dimensions of high-performance work systems: enriched jobs, high involvement management, employee voice, and motivational supports. Hypothesized associations are tested using multilevel models and data from Britain's Workplace Employment Relations Survey of 2004 (WERS2004). Results show that enriched jobs are positively associated with both measures of well-being: job satisfaction and anxietyâcontentment. Voice is positively associated with job satisfaction, and motivational supports with neither measure. The results for high involvement management are not as predicted because it increases anxiety and is independent of job satisfaction
Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV
Results are presented from a search for a W' boson using a dataset
corresponding to 5.0 inverse femtobarns of integrated luminosity collected
during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV.
The W' boson is modeled as a heavy W boson, but different scenarios for the
couplings to fermions are considered, involving both left-handed and
right-handed chiral projections of the fermions, as well as an arbitrary
mixture of the two. The search is performed in the decay channel W' to t b,
leading to a final state signature with a single lepton (e, mu), missing
transverse energy, and jets, at least one of which is tagged as a b-jet. A W'
boson that couples to fermions with the same coupling constant as the W, but to
the right-handed rather than left-handed chiral projections, is excluded for
masses below 1.85 TeV at the 95% confidence level. For the first time using LHC
data, constraints on the W' gauge coupling for a set of left- and right-handed
coupling combinations have been placed. These results represent a significant
improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe
Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV
A search for a Higgs boson decaying into two photons is described. The
analysis is performed using a dataset recorded by the CMS experiment at the LHC
from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an
integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross
section of the standard model Higgs boson decaying to two photons. The expected
exclusion limit at 95% confidence level is between 1.4 and 2.4 times the
standard model cross section in the mass range between 110 and 150 GeV. The
analysis of the data excludes, at 95% confidence level, the standard model
Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The
largest excess of events above the expected standard model background is
observed for a Higgs boson mass hypothesis of 124 GeV with a local significance
of 3.1 sigma. The global significance of observing an excess with a local
significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is
estimated to be 1.8 sigma. More data are required to ascertain the origin of
this excess.Comment: Submitted to Physics Letters
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