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Quantitative SPECT by attenuation correction of the projection set using transmission data: evaluation of a method

A method for measuring attenuation coefficients in single-photon emission tomography (SPECT) is described and evaluated, together with a method for attenuation correction using these measured attenuation coefficients. Build-up, caused by scattered photons, is corrected for by a simple substitution in the algorithms. Transmission studies are performed with a 99mTc- or 57Co flood source, and emissio

PMMA particles and pressure - a study of the osteolytic properties of two agents proposed to cause prosthetic loosening

Amongst the wear debris particles implicated in the particle hypothesis for prosthetic loosening are polymethylmethacrylate (PMMA), and particularly PMMA with barium sulphate contrast agent. Another suggested cause for loosening is hydrostatic pressure. PMMA particles were combined with hydrostatic pressure in a study to investigate whether there could be a synergistic or additive effect between t

Does an active sun exposure habit lower the risk of venous thrombotic events? A D-lightful hypothesis

Background: Venous and arterial thrombotic complications exhibit a seasonal variation, with risk peaking in winter and dropping to a nadir in summer. We sought a possible correlation between sun exposure habits and venous thromboembolism (VTE) events. Methods: This was a cohort study comprising 40 000 women (1000 per year of age from 25 to 64 years) who were drawn from the southern Swedish populat

Possible evidence for the ejection of a supermassive black hole from an ongoing merger of galaxies

Attempts of Magain et al. to detect the host galaxy of the bright quasi-stellar object (QSO) HE0450-2958 have not been successful. We suggest that the supermassive black hole (SMBH) powering the QSO was ejected from the observed ultraluminous infrared galaxy (ULIRG) at the same redshift and at 1.5 arcsec distance. Ejection could have been caused either by recoil due to gravitational wave emission

Novel "plum pudding" as potential drug-eluting stent coatings : Controlled release of fluvastatin

This study evaluated novel structural motifs known as "plum pudding" gels as potential drug-eluting stent coatings. Controlled delivery of a HMG-CoA reductase inhibitor (statin) from the intravascular stent surface represents a potential therapeutic modality for prevention of in-stent restenosis (ISR). In this study, gels were comprised of fluvastatin-loaded thermoresponsive microgel particles con

High-resolution x-ray structure of human aquaporin 5

Human aquaporin 5 (HsAQP5)facilitates the transport of water across plasma membranes and has been identified within cells of the stomach, duodenum, pancreas, airways, lungs, salivary glands, sweat glands, eyes, lacrimal glands, and the inner ear. AQP5, like AQP2, is subject to posttranslational regulation by phosphorylation, at which point it is trafficked between intracellular storage compartment

Role of Linker Groups between Hydrophilic and Hydrophobic Moieties of Cationic Surfactants on Oligonucleotide-Surfactant Interactions

The interaction between DNA and amino-acid-based surfactants with different linker groups was investigated by gel electrophoresis, ethidium bromide exclusion assays, circular dichroism, and melting temperature determinations. The Studies showed that the strength of the interaction between the oligonucleotides and the surfactants is highly dependent oil the linker of the surfactant. For ester surfa

Human resources and access to maternal health care

The lack of human resources is one of the main bottlenecks to achieving the Millennium Development Goals on maternal and child health. A coherent national policy, recognized across government, needs to be in place to overcome this especially in countries severely affected by HIV/AIDS. Such a policy should cover selection of pre-service students, the qualifications of trainers and training sites, s

The evolution of sex ratios and sex-determining systems

Sex determination is a fundamental process governed by diverse mechanisms. Sex ratio selection is commonly implicated in the evolution of sex-determining systems, although formal models are rare. Here, we argue that, although sex ratio selection can induce shifts in sex determination, genomic conflicts between parents and offspring can explain why single-factor systems (e.g. XY/XX or ZW/ZZ) are co

Comparison of genotyping methods by application to Salmonella livingstone strains associated with an outbreak of human salmonellosis

During 2000 and 2001, an outbreak of human salmonellosis occurred in Sweden and Norway, caused by Salmonella livingstone. In this study, the genotypic differences between three strains obtained from food sources during the outbreak, two human strains and 27 more or less unrelated strains were analysed, using the three methods; automated ribotyping, pulsed field get electrophoresis (PFGE) and rando

Superimposed single impulse and pulse train electrical stimulation: A quantitative assessment during submaximal isometric knee extension in young, healthy men

Superimposed electrical stimulation techniques can be used to detect central activation failure (CAF), defined as incomplete central nervous system recruitment, suboptimal activation of motor units, or both. The purpose of this study was to evaluate superimposed electrical stimulation techniques to be used to detect CAF during isometric knee extension. We performed three sets of experiments and co

Antiandrogen exposure in utero disrupts expression of desert hedgehog and insulin-like factor 3 in the developing fetal rat testis

Testicular development is an androgen-dependent process, and fetal exposure to antiandrogens disrupts male sexual differentiation. A variety of testicular disorders may result from impaired development of fetal Leydig and Sertoli cells. We hypothesized that antiandrogenic exposure during fetal development interferes with desert hedgehog (Dhh) signaling in the testis and results in impaired Leydig

Cerebral amyloid angiopathy, white matter lesions and Alzheimer encephalopathy - A histopathological assessment

To test the hypothesis that the cerebral amyloid angiopathy (CAA) of Alzheimer's disease (AD) is quantitatively associated with white matter lesions (WML), the brains of 63 demented patients exhibiting varying degrees of Alzheimer encephalopathy (AE) were examined, along with those of 10 nondemented control cases. The ratio of amyloid-positive to amyloid-negative vessels in the leptomeninges of th

Precise detection of pH inside large unilamellar vesicles using membrane-impermeable dendritic porphyrin-based nanoprobes.

Accurate real-time measurements of proton concentration gradients are pivotal to mechanistic studies of proton translocation by membrane-bound enzymes. Here we report a detailed characterization of the pH-sensitive fluorescent nanoprobe Glu(3), which is well suited for pH measurements in microcompartmentalized biological systems. The probe is a polyglutamic porphyrin dendrimer in which multiple ca

A New Necessary Condition for Shortest Path Routing

In shortest path routing, traffic is routed along shortest paths defined by link weights. However, not all path systems are feasible in that they can be realized in this way. This is something which needs to be taken into account when searching for a set of paths that minimize capacity consumption. In this paper, we discuss a new necessary condition that can be used during search to prune infeasib

Evidence for rapid environmental changes in low latitudes during the Late Silurian Lau Event: the Burgen-1 drillcore, Gotland, Sweden

Erosional outliers are an important component of the Ludlow (Late Silurian) stratigraphy of Gotland, Sweden. However, due to the poor degree of exposure, outcrop studies have not revealed a detailed section from any of these outliers. The first complete stratigraphy of such an erosional remnant. the Burgen outlier, is presented here, based on the recently recovered Burgen-1 drillcore. Stratigraphi

Melatonin restores impaired contractility in aged guinea pig urinary bladder

Urinary bladder disturbances are frequent in the elderly population but the responsible mechanisms are poorly understood. This study evaluates the effects of aging on detrusor myogenic contractile responses and the impact of melatonin treatment. The contractility of bladder strips from adult, aged and melatonin-treated guinea pigs was evaluated by isometric tension recordings. Cytoplasmatic calciu