4,779 research outputs found
Hemostatic function in young subjects with central obesity: relationship with left ventricular function
This study was designed to evaluate coagulation and fibrinolysis activity and their relationship with left ventricular function in young obese subjects with central fat distribution. We assessed coagulation and fibrinolysis activity by evaluation of factor VII activity, fibrinogen and plasminogen, plasminogen activator inhibitor (PAI), and tissue plasminogen activator antigen basally (tPA1) and after venous occlusion (tPA2). These measures were evaluated in young (< 40 years) obese subjects with central fat distribution (n = 19) and in comparable lean subjects (n = 20). Blood glucose, triglycerides, total and high-density lipoprotein (HDL) cholesterol, apolipoprotein (apo) A1 and apo B, fasting immunoreactive insulin, and lipoprotein(a) levels were also measured by current methods. Left ventricular ejection fraction (LVEF) and peak filling rate (PFR) determined by radionuclide angiocardiography and left ventricular mass (LVM) and LVM indexed for body height (LVM/H) determined by echocardiographic study were calculated. Central obesity was evaluated by the waist to hip ratio (WHR) according to the criteria of the Italian Consensus Conference of Obesity. Factor VII (P < .001), fibrinogen (P < .001), plasminogen (P < .001), PAI activity (P < .001), tPA1 (P < .02), fasting blood glucose (P < .01), apo B (P < .02), and immunoreactive insulin (P < .01) were significantly higher in obese than in lean subjects. In contrast, HDL cholesterol (P < .01), tPA2 (P < .01), LVEF (P < .001), and PFR (P < .02) were significantly lower in obese than in lean subjects. In all subjects, WHR correlated directly with fibrinogen and inversely with tPA2; LVEF correlated inversely with tPA1, PAI, and fibrinogen; and PFR correlated inversely with factor VII activity
Inter-familial and intra-familial phenotypic variability in three Sicilian families with Anderson-Fabry disease.
Abstract
BACKGROUND:
Anderson-Fabry disease (AFD) is an inborn lysosomal enzymopathy resulting from the deficient or absent activity of the lysosomal exogalactohydrolase, α-galactosidase A. This deficiency, results in the altered metabolism of glycosphingolipids which leads to their accumulation in lysosomes, thus to cellular and vascular dysfunction. To date, numerous mutations (according to recent data more than 1000 mutations) have been reported in the GLA intronic and exonic mutations. Traditionally, clinical manifestations are more severe in affected hemizygous males than in females. Nevertheless, recent studies have described severe organ dysfunction in women.
THE AIM OF THE STUDY:
This study reports clinical, biochemical, and molecular findings of the members of three Sicilian families. The clinical history of these patients highlights a remarkable interfamilial and intrafamilial phenotypic variability which characterizes Fabry disease relative to target organs and severity of clinical manifestations.
DISCUSSION:
Our findings, in agreement with previous data, report a little genotype-phenotype correlation for the disease, suggesting that the wide phenotypic variability of Anderson-Fabry disease is not completely ascribable to different gene mutations but other factors and mechanisms seem to be involved in the pathogenesis and clinical expression of the disease. Moreover, this study emphasies the importance of pedigree analysis in the family of each proband for identifying other possibly affected relatives
Time evolution of 1D gapless models from a domain-wall initial state: SLE continued?
We study the time evolution of quantum one-dimensional gapless systems
evolving from initial states with a domain-wall. We generalize the
path-integral imaginary time approach that together with boundary conformal
field theory allows to derive the time and space dependence of general
correlation functions. The latter are explicitly obtained for the Ising
universality class, and the typical behavior of one- and two-point functions is
derived for the general case. Possible connections with the stochastic Loewner
evolution are discussed and explicit results for one-point time dependent
averages are obtained for generic \kappa for boundary conditions corresponding
to SLE. We use this set of results to predict the time evolution of the
entanglement entropy and obtain the universal constant shift due to the
presence of a domain wall in the initial state.Comment: 27 pages, 10 figure
Recommended from our members
Interspecies differences in protein expression do not impact the spatiotemporal regulation of glycoprotein VI mediated activation
Background
Accurate protein quantification is a vital prerequisite for generating meaningful predictions when using systems biology approaches, a method that is increasingly being used to unravel the complexities of sub cellular interactions and as part of the drug discovery process. Quantitative proteomics, flow cytometry and western blotting have been extensively used to define human platelet protein copy numbers, yet for mouse platelets, a model widely used for platelet research, evidence is largely limited to a single proteomic dataset in which the total amount of proteins were generally comparatively higher than those found in human platelets.
Objectives
To investigate the functional implications of discrepancies between levels of mouse and human proteins in the GPVI signalling pathway using a systems pharmacology model of GPVI
Methods
The protein copy number of mouse platelet receptors was determined using flow cytometry. The Virtual Platelet, a mathematical model of Glycoprotein VI (GPVI) signalling, was used to determine the consequences of protein copy number differences observed between human and mouse platelets.
Results and conclusion
Despite the small size of mouse platelets compared to human platelets they possessed a greater density of surface receptors alongside a higher concentration of intracellular signalling proteins. Surprisingly the predicted temporal profile of Syk activity was similar in both species with predictions supported experimentally. Super resolution microscopy demonstrates that the spatial distribution of Syk is similar between species, suggesting that the spatial distribution of receptors and signalling molecules in activated platelets, rather than their copy number, is important for signalling pathway regulation
Cognitive impairment induced by delta9-tetrahydrocannabinol occurs through heteromers between cannabinoid CB1 and serotonin 5-HT2A receptors
Delta-9-tetrahydrocannabinol (THC), the main psychoactive compound of marijuana, induces numerous undesirable effects, including memory impairments, anxiety, and dependence. Conversely, THC also has potentially therapeutic effects, including analgesia, muscle relaxation, and neuroprotection. However, the mechanisms that dissociate these responses are still not known. Using mice lacking the serotonin receptor 5-HT2A, we revealed that the analgesic and amnesic effects of THC are independent of each other: while amnesia induced by THC disappears in the mutant mice, THC can still promote analgesia in these animals. In subsequent molecular studies, we showed that in specific brain regions involved in memory formation, the receptors for THC and the 5-HT2A receptors work together by physically interacting with each other. Experimentally interfering with this interaction prevented the memory deficits induced by THC, but not its analgesic properties. Our results highlight a novel mechanism by which the beneficial analgesic properties of THC can be dissociated from its cognitive side effects
Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead.
Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effects. No dose-response information was found for the remaining 26% (22/85). Our analysis suggests that the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies. Additional basic research on carcinogenesis and research focused on low-dose effects of chemical mixtures needs to be rigorously pursued before the merits of this hypothesis can be further advanced. However, the structure of the World Health Organization International Programme on Chemical Safety 'Mode of Action' framework should be revisited as it has inherent weaknesses that are not fully aligned with our current understanding of cancer biology
Decoupling property of the supersymmetric Higgs sector with four doublets
In supersymmetric standard models with multi Higgs doublet fields,
selfcoupling constants in the Higgs potential come only from the D-terms at the
tree level. We investigate the decoupling property of additional two heavier
Higgs doublet fields in the supersymmetric standard model with four Higgs
doublets. In particular, we study how they can modify the predictions on the
quantities well predicted in the minimal supersymmetric standard model (MSSM),
when the extra doublet fields are rather heavy to be measured at collider
experiments. The B-term mixing between these extra heavy Higgs bosons and the
relatively light MSSM-like Higgs bosons can significantly change the
predictions in the MSSM such as on the masses of MSSM-like Higgs bosons as well
as the mixing angle for the two light CP-even scalar states. We first give
formulae for deviations in the observables of the MSSM in the decoupling region
for the extra two doublet fields. We then examine possible deviations in the
Higgs sector numerically, and discuss their phenomenological implications.Comment: 26 pages, 24 figures, text sligtly modified,version to appear in
Journal of High Energy Physic
One-Loop Calculation of the Oblique S Parameter in Higgsless Electroweak Models
We present a one-loop calculation of the oblique S parameter within Higgsless
models of electroweak symmetry breaking and analyze the phenomenological
implications of the available electroweak precision data. We use the most
general effective Lagrangian with at most two derivatives, implementing the
chiral symmetry breaking SU(2)_L x SU(2)_R -> SU(2)_{L+R} with Goldstones,
gauge bosons and one multiplet of vector and axial-vector massive resonance
states. Using the dispersive representation of Peskin and Takeuchi and imposing
the short-distance constraints dictated by the operator product expansion, we
obtain S at the NLO in terms of a few resonance parameters. In
asymptotically-free gauge theories, the final result only depends on the
vector-resonance mass and requires M_V > 1.8 TeV (3.8 TeV) to satisfy the
experimental limits at the 3 \sigma (1\sigma) level; the axial state is always
heavier, we obtain M_A > 2.5 TeV (6.6 TeV) at 3\sigma (1\sigma). In
strongly-coupled models, such as walking or conformal technicolour, where the
second Weinberg sum rule does not apply, the vector and axial couplings are not
determined by the short-distance constraints; but one can still derive a lower
bound on S, provided the hierarchy M_V < M_A remains valid. Even in this less
constrained situation, we find that in order to satisfy the experimental limits
at 3\sigma one needs M_{V,A} > 1.8 TeV.Comment: 34 pages, 9 figures. Version published in JHEP. Some references and
sentences have been added to facilitate the discussio
Dynamics of a Quantum Phase Transition and Relaxation to a Steady State
We review recent theoretical work on two closely related issues: excitation
of an isolated quantum condensed matter system driven adiabatically across a
continuous quantum phase transition or a gapless phase, and apparent relaxation
of an excited system after a sudden quench of a parameter in its Hamiltonian.
Accordingly the review is divided into two parts. The first part revolves
around a quantum version of the Kibble-Zurek mechanism including also phenomena
that go beyond this simple paradigm. What they have in common is that
excitation of a gapless many-body system scales with a power of the driving
rate. The second part attempts a systematic presentation of recent results and
conjectures on apparent relaxation of a pure state of an isolated quantum
many-body system after its excitation by a sudden quench. This research is
motivated in part by recent experimental developments in the physics of
ultracold atoms with potential applications in the adiabatic quantum state
preparation and quantum computation.Comment: 117 pages; review accepted in Advances in Physic
- …
