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A comprehensive analysis of the androgen receptor gene and risk of breast cancer: results from the National Cancer Institute Breast and Prostate Cancer Cohort Consortium (BPC3)

Introduction Androgens have been hypothesised to influence risk of breast cancer through several possible mechanisms, including their conversion to estradiol or their binding to the oestrogen receptor and/ or androgen receptor ( AR) in the breast. Here, we report on the results of a large and comprehensive study of the association between genetic variation in the AR gene and risk of breast cancer

Species loss leads to community closure

Global extinction of a species is sadly irreversible. At a local scale, however, extinctions may be followed by re-invasion. We here show that this is not necessarily the case and that an ecological community may close its doors for re-invasion of species lost from it. Previous studies of how communities are assembled have shown that there may be rules for that process and that limitations are set

Decoupler and PID controller design of TITO systems

This paper treats controller design and tuning for systems with two input signals and two output signals in the process industry. Two design methods that can be combined to form a core in an algorithm for automatic design and tuning for the considered systems are presented. The proposed controller consists of a decoupler and a diagonal PID controller. The decoupler has the property that as little

NAGLU mutations underlying Sanfilippo syndrome type B

Sanfilippo syndrome type B (mucopolysaccharidosis III B) is a rare autosomal recessive disease caused by deficiency of alpha-N-acetylglucosaminidase, one of the enzymes required for the lysosomal degradation of heparan sulfate. The gene for this enzyme, NAGLU, recently was isolated, and several mutations were characterized. We have identified, in amplified exons from nine fibroblast cell lines der

Testing for the Presence of Thermal Pretreatment of Flint in the Mesolithic and Neolithic of Sweden

Through ethnographic accounts, the method of heat treatment of silica materials to improve the flaking qualities is shown to have been known almost worldwide. Some mesolithic and neolithic flint artifacts from southern Sweden were examined in order to determine if they too were heat treated. From several methods proving or indicating thermal alteration of flint, analysis using scanning electron mi

Binding of hexadecyltrimethylammonium bromide to starch polysaccharides. Part II. Calorimetric study

Isothermal titration calorimetry was used to study the interaction between hexadecyltrimethylammonium bromide, CTAB, and three starch polysaccharides, amylose from potato, amylopectin from potato and amylopectin from barley. The enthalpy change for consecutive additions of CTAB to starch polysaccharide solutions were measured at 27degreesC. The starch-CTAB interaction enthalpies, DeltaH(f), were c

Genetic amniocentesis:a risk factor for preterm delivery?

Objective: To determine whether genetic amniocentesis performed in the second trimester of pregnancy is associated with the risk of preterm delivery. Study design: Case–control study performed in several departments of obstetrics and gynaecology of nine European countries. Three thousand and ninety-one preterm births and 5298 controls randomly selected from singleton births born at term during 199

A catalytic and mechanistic investigation of a PCP pincer palladium complex in the Stille reaction

In an improved procedure, the complex {2,6-bis[(diphenylphosphino)methyl]benzene}chloropalladium(II) (1) was synthesised as its THF adduct and the structure was determined by X-ray crystallography. The catalytic properties of the derivative {2,6-bis[(diphenylphosphino)methyl]benzene} (trifluoroacetato)palladium(II) (2) was investigated in the Stille reaction. Complex 2 proves to be an excellent ca

Vascular function and sphingosine-1-phosphate regulate development of the dorsal pancreatic mesenchyme

Early growth and differentiation of the pancreatic endoderm is regulated by soluble factors from the pancreatic mesenchyme. Previously, we demonstrated that N-cadherin-deficient mice lack a dorsal pancreas, due to a critical role of N-cadherin in dorsal pancreatic mesenchymal cell survival. Here, we show that restoring cardiac and circulatory function in N-cadherin null mice by cardiac-specific ex

Differentiation induced by physiological and pharmacological stimuli leads to increased antigenicity of human neuroblastoma cells

Sympathetic neuronal differentiation is associated with favorable prognosis of neuroblastoma (NB), the most common extra-cranial solid tumor of early childhood. Differentiation agents have proved useful in clinical protocols of NB treatment, but using them as a sole treatment is not sufficient to induce tumor elimination in patients. Therefore, complementary approaches, such as immunotherapy, are

Temperature and salt content regimes in three shallow ice-covered lakes 1. Temperature, salt content, and density structure

A field study on the temperature, salt content, and density regime in three shallow ice-covered Karelian lakes is presented. The measurements show that the heat content increases during the whole ice-covered period. At ice formation a weak stable stratification existed in the lakes, with average temperatures about 1 degrees C. Thereafter, the stability of the stratification gradually increased, ma

Using Delphi-AHP method to survey major factors causing urban plan implementation failure

This study presents a framework to evaluate factors influencing implementation of urban plans. An integrated Delphi-AHP method is utilized to identify important factors and their quantitative importance causing failure of urban plan implementation. Delphi method has been used to survey major factors and Analytical Hierarchy Process (AHP) method has been utilized to define their significance, in a

Water and urea interactions with the native and unfolded forms of a beta-barrel protein.

A fundamental understanding of protein stability and the mechanism of denaturant action must ultimately rest on detailed knowledge about the structure, solvation, and energetics of the denatured state. Here, we use 17O and 2H magnetic relaxation dispersion (MRD) to study urea-induced denaturation of intestinal fatty acid-binding protein (I-FABP). MRD is among the few methods that can provide molec

New approaches to the analysis of enzymatically hydrolyzed methyl cellulose. Part 1. Investigation of the influence of structural parameters on the extent of degradation

Six methyl celluloses (MCs), one with a degree of substitution (DS) of 1.32 and five with DS between 1.83 and 1.88, were thoroughly investigated. Monomer composition and methyl distribution in the polymer chain were analyzed after total or partial random hydrolysis and appropriate derivatization with gas chromatography ( GC) and mass spectrometry (MS), respectively, and used as reference data. The

Frequency estimation by demodulation of two complex signals

This paper presents a method for frequency estimation in a power system by demodulation of two complex signals. In power system analysis, the αβ-transform is used to convert three phase quantities to a complex quantity where the real part is the in-phase component and the imaginary part is the quadrature component. This complex signal is demodulated with a known complex phasor rotating in opposite

Neuropeptide Y in sympathetic co-transmission: recent advances in the search for neuropeptide Y antagonists

Since the discovery of neuropeptide Y which is co-stored and co-operate with noradrenaline (NA) in sympathetic nerve fibers, several scientific groups have searched for structures with neuropeptide Y antagonistic properties. Research has mainly focused on various peptide fragments which originate from or are related to the neuropeptide Y sequence. Some non-peptide antagonists have been proposed bu

Ex vivo evaluation of nonacceptable donor lungs

Background. Only a minority of the potential candidates for lung donation are considered suitable, using current evaluation methods. A new method for ex vivo evaluation, with the potential for reconditioning of marginal and nonacceptable lungs, has been developed. This is a report of the ex vivo evaluation of six donor lungs deemed nonacceptable (arterial oxygen pressure less than 40 kPa) by the S

Rheumatoid arthritis: what does it cost and what factors are driving those costs? Results of a survey in a community-derived population in Malmo, Sweden

Objective: We sought to investigate the cost of living with rheumatoid arthritis (RA) and evaluate the influence of both demographics and specific disease characteristics on these costs. Methods: We used a population-based questionnaire to survey 895 patients living in the city of Malmo, Sweden, during 2002. Data were obtained on direct resource consumption, investments, informal care and work cap

Block polyelectrolytes and colloidal stability.

We simulate interactions between charged flat surfaces in the presence of block polymers, where the end blocks carry a charge opposite to the surfaces. Using a recently developed simulation technique, we allow full equilibrium, i.e. the chemical potential of the polyelectrolyte is retained as the separation is changed. In general, the block polyions will adsorb strongly enough to overcharge the su