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Neutrophil granules: a library of innate immunity proteins

Gene expression profiling has revealed that circulating neutrophils rest between two major bursts of transcriptional and protein synthetic activities. The first occurs in the bone marrow. This equips the neutrophil with stocks of innate defense armory that are packaged into different granule subsets. The second burst occurs when the neutrophil exits circulation and migrates into tissues to find, c

Horizontal gene transfer: a critical view

It has been suggested that horizontal gene transfer (HGT) is the "essence of phylogeny." In contrast, much data suggest that this is an exaggeration resulting in part from a reliance on inadequate methods to identify HGT events. In addition, the assumption that HGT is a ubiquitous influence throughout evolution is questionable. Instead, rampant global HGT is likely to have been relevant only to pr

Dialkyl and Methyl-Alkyl Zirconocenes: Synthesis and Characterization of Zirconocene-Alkyls That Model the Polymeryl Chain in Alkene Polymerizations

Zirconocene precatalysts with sterically bulky alkyl groups were designed as model systems for the propagating species in zirconocene-catalyzed alkene polymerization. Specialty alkyllithium reagents Li(CH2CEt3) and Li(CH2CMe2CH2Ph) were prepared and utilized in the synthesis of dialkyl and methyl-alkyl zirconocenes of the form CpCp*ZrR2, Cp2Zr(CH3)(R), and CpCp*Zr(CH3)(R) (Cp = (5-C5H5); Cp* = (5-

Lead time associated with screening for prostate cancer

Screening serum levels of prostate-specific antigen (PSA) is now a major strategy for early detection of prostate cancer (PC). Quantification of the lead time thus obtained is important both for understanding the development of PC and for evaluating the advantages and disadvantages of widespread screening. In our study, 1,233 randomly selected men living in Stockholm in 1988 were invited to partic

Cysteine proteases in Langerhans cells limits presentation of cartilage derived type II collagen for autoreactive T cells.

Development of type-II collagen (CII)-induced arthritis (CIA) is dependent on activation of CII-reactive T cells. Dendritic cells (DCs) are believed to play a crucial role in antigen-specific priming of T cells but it is still unclear how the CII-reactive T cells are primed since Langerhans cells (LCs) are poor antigen-presenting cells for CII. In the present study we show that LCs, treated with c

Segmentation of the Body and Lungs from Compton Scatter and Photopeak Window Images in SPECT: A Monte Carlo Investigation

In SPECT imaging of the chest, nonuniform attenuation correction requires use of a patient specific attenuation (p)map. Such a map can be obtained by estimating the regions of 1)the lungs and 2) the soft tissues and bones, and then assigning an appropriate value of attenuation coefficient (p) to each region. We proposed a method to segment such regions from the Compton scatter and photopeak window

Harmonic morphisms from the classical compact semisimple Lie groups

In this article, we introduce a new method for manufacturing harmonic morphisms from semi-Riemannian manifolds. This is employed to yield a variety of new examples from the compact Lie groups SO(n), SU(n) and Sp(n) equipped with their standard Riemannian metrics. We develop a duality principle and show how this can be used to construct the first known examples of harmonic morphisms from the non-co

Specific plasma membrane aquaporins of the PIP1 subfamily are expressed in sieve elements and guard cells

Background information. Transmembrane water flow is aided by water-specific channel proteins, aquaporins. Plant genomes code for approx. 35 expressed and functional aquaporin isoforms. Plant aquaporins fall into four different subfamilies of which the PIPS (plasma membrane intrinsic proteins) constitute the largest and evolutionarily most conserved subfamily with 13 members in Arabidopsis and maiz

A link between Helicobacter pylori and/or Chlamydia spp. infections and atherosclerosis

Antibodies to Helicobacter pylori, Chlamydia spp. and Mycobacterium bovis were determined in patients with coronary heart disease, H. pylori-related dyspepsia, and tuberculosis, and healthy controls. Enzyme-linked immunosorbent assay was conducted with a glycine extract and CagA protein of H. pylori, chlamydial lipopolysaccharide and mycobacterial heat shock protein Hsp65. The prevalence of anti-g

Mediterranean dietary pattern and prediction of all-cause mortality in a US population - Results from the NIH-AARP diet and health study

Background: The Mediterranean diet has been suggested to play a beneficial role for health and longevity. However, to our knowledge, no prospective US study has investigated the Mediterranean dietary pattern in relation to mortality. Methods: Study participants included 214 284 men and 166 012 women in the National Institutes of Health (NIH)-AARP ( formerly known as the American Association of Ret

Inhibition of mammalian legumain by some cystatins is due to a novel second reactive site

We have investigated the inhibition of the recently identified family C13 cysteine peptidase, pig legumain, by human cystatin C. The cystatin was seen to inhibit enzyme activity by stoichiometric 1:1 binding in competition with substrate. The Ki value for the interaction was 0.20 nM, i.e. cystatin C had an affinity for legumain similar to that for the papain-like family C1 cysteine peptidase, cath

The effect of the vasoactive intestinal polypeptide agonist Ro 25-1553 on induced tone in isolated human airways and pulmonary artery

Ro 25-1553 is a metabolically stable analogue of endogenous vasoactive intestinal polypeptide (VIP). This compound is a potent bronchodilator in vitro as well as in vivo. Moreover, Ro 25-1553 has been shown to be highly selective of the VPAC2 receptor. We assessed the effect of Ro 25-1553 on isolated human bronchi and pulmonary arteries in vitro. Macroscopically normal human airways and pulmonary

Application of heat pump systems for energy conservation in paper drying

Drying is one of the most energy intensive and common operations in the chemical and process industries. Scope for energy recovery is substantial, particularly from the latent heat of the exhaust moist air. Using real operating data from a major Swedish mill, optimal energy conservation strategies were investigated using different heat pump systems in paper drying. Simulation results are compared

Characterization of the interphase in PPO/PMMA blends compatibilized by P(S-g-EO)

The influence of a poly(styrene-graft-ethylene oxide) (P(S-g-EO)) copolymer on poly(2,6-dimethyl-p-phenylene oxide)/poly(methyl methacrylate) (PPO/PMMA) blends was studied by a number of different techniques in order to characterize the properties of the interphase. Scanning electron microscopy shows that the copolymer reduces the dispersed phase size, and dynamic mechanical spectroscopy (DMS) rev