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Dictyostelium discoideum salvages purine deoxyribonucleosides by highly specific bacterial-like deoxyribonucleoside kinases

The salvage of deoxyribonucleosides in the social amoeba Dictyostelium discoideum, which has an extremely A + T-rich genome, was investigated. All native deoxyribonucleosides were phosphorylated by D. discoideum cell extracts and we subcloned three deoxyribonucleoside kinase (dNK) encoding genes. D. discoideum thymidine kinase was similar to the human thymidine kinase 1 and was specific for thymid

Direct electron transfer between ligninolytic redox enzymes and electrodes

The electrochemistry of the ligninolytic redox enzymes, which include lignin peroxidase, manganese peroxidase and laccase and possibly also cellobiose dehydrogenase, is reviewed and discussed in conjunction with their basic biochemical characteristics. It is shown that long-range electron transfer between these enzymes and electrodes can be established and their ability to degrade lignin through a

Relationship between somatic cell count, individual leukocyte populations and milk components in bovine udder quarter milk

The somatic cell count (SCC) in bovine milk is an indicator of udder health and milk quality. Individual cell populations, i.e., macrophages, lymphocytes and polymorphonuclear neutrophils, were identified and their relationship to milk components such as acute-phase proteins (serum amyloid A (SAA) and alpha(1)-acid glycoprotein), lactic acid and lactoferrin (LF), as well as protein, fat and lactos

Warum können wir Fahrrad fahren

Beim Fahrradfahren arbeitet der Mensch als Regler. Das wird beim Balancieren des Fahrrades besonders offensichtlich, denn das Fahrrad ist instabil. In diesem Beitrag wird untersucht, unter welchen Bedingungen es möglich ist, das Fahrrad mit einem so einfachen Reglergesetz zu balancieren, dass Menschen dieses Reglergesetz ohne Mühe realisieren können. Dabei wird nicht nur die jedem Radfahrer bekann

Body mass index as a predictor of fracture risk: A meta-analysis

Low body mass index (BMI) is a well-documented risk factor for future fracture. The aim of this study was to quantify this effect and to explore the association of BMI with fracture risk in relation to age, gender and bone mineral density (BMD) from an international perspective using worldwide data. We studied individual participant data from almost 60,000 men and women from 12 prospective populat

Theory, boundaries and political communication - The uses of disparity

While the themes of fragmentation and insufficient coherence dominated discussions in the field of media and communication studies a decade ago, today they seem less urgent, even if at times still problematic. In terms of theory, the field is well served by its permeable boundaries, since much of its theory is 'imported'. Moreover, theory needs nondoctrinaire critical stances to address the distre

The GSSP of the second (Upper) stage of the Lower Ordovician series: Diabasbrottet at Hunneberg, province of Vastergotland, southwestern Sweden

Diabasbrottet, selected by the International Subcommisson on Ordovician Stratigraphy and in 2002 ratified by the International Commission on Stratigraphy as the GSSP of the Second (Upper) Stage of the Lower Ordovician, is located on the Hunneberg Mountain in southwestern Sweden. The stratigraphic succession represents an outer shelf environment near the Baltic Shield margin. The shale-dominated, b

System Identification using LQG-Balanced Model Reduction,

System identification of linear multivariable dy-namic models based on discrete-time data can be performed using a algorithm combining linear regression and LQG-balanced model reduction. The approach is applicable also to unstable system dynamics and it provides balanced models for optimal linear prediction and control.

Experimental and computational evaluation of mass transfer resistance of paper dryer fabrics

The mass transfer aspects of synthetic dryer fabrics used in multi-cylinder paper dryers were investigated both experimentally and computationally. Experiments were performed in a convective dryer to determine which characteristics of the fabric are instrumental in controlling the drying rate. Results obtained from twelve different fabrics showed that neither the permeability nor the porosity of t

Gestational age-dependent reference values for pH in umbilical cord arterial blood at term

OBJECTIVE: Despite a change of fetal physiologic and biochemical functions with gestational age, stationary umbilical cord acid-base reference values are used as measures of obstetric care quality. The aim of this study was to assess the risk of low Apgar score relative to low pH when using stationary versus gestational age-adjusted reference values. METHODS: Umbilical artery pH was determined in

Cytokine induced airway hyperreactivity characterized in an in-vitro model of asthma

Popular Abstract in Swedish Astma är en sjukdom som karakteriseras av upprepade anfall av andningssvårigheter, orsakade av kramp, slemhinnesvullnad och segt sekret i luftvägarna. Den finns beskriven i texter redan från det antika Grekland och rapporteras idag vara en sjukdom med utbredning över hela vårt klot. Astma är den vanligaste kroniska sjukdomen bland barn och är oavsett ålder den vanligastAsthma is a chronic disorder of the lower airways, characterized by inflammation and hyperreactivity. Pro-inflammatory cytokines like tumour necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) are known to play important roles in the pathogenesis, but our knowledge how these cytokines contribute to the development of airway hyperreactivity is limited. The aims of the present study

Top-down and bottom-up processes in grassland and forested streams

The influence of predatory fish on the structure of stream food webs may be altered by the presence of forest canopy cover, and consequent differences in allochthonous inputs and primary production. Eight sites containing introduced brown trout (Salmo trutta) and eight sites that did not were sampled in the Cass region, South Island, New Zealand. For each predator category, half the sites were loc

A structural insight into the inhibition of human and Leishmania donovani ornithine decarboxylases by 3-aminooxy-1-aminopropane

The critical role of polyamines in key processes such as cell growth, differentiation and macromolecular synthesis makes the enzymes involved in their synthesis potential targets in the treatment of certain types of cancer and parasitic diseases. Here we present a study on the inhibition of human and Leishmania donovani ODC (ornithine decarboxylase), the first committed enzyme in the polyamine bio