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Selection of hammerhead ribozyme variants with low Mg2+ requirement: Importance of stem-loop II

Variants of the hammerhead ribozyme with high in trans (intermolecular) cleavage activity at low Mg2- concentrations were in vitro selected from a library with 78 nucleotides randomised in the core and in helix II. The most active hammerhead ribozyme selected had e sequence as the consensus ribozyme in the core but only two base pairs in stem II, G(10.1)-C(11.1) and U(10.2)-A(11.2), and a tetrauri

Glomerular sieving of three neutral polysaccharides and bikunin in rat. - Effects of molecular size and conformation.

Aim: Polysaccharides and many other non-protein polymers generally have a more open, flexible and asymmetrical structure compared with globular proteins. For a given molecular weight (MW), the Stokes–Einstein radius (ae) of the following polymers increases in the order: Ficoll < dextran ≤ pullulan < polyethylene oxide (PEO). We have tested the hypothesis that such an increase in 'molecular extensi

Chlorhexidine for prevention of neonatal colonization with group B streptococci. II. Chlorhexidine concentrations and recovery of group B streptococci following vaginal washing in pregnant women

The effect of a single washing of the urogenital tract with 0.5 g/l chlorhexidine was studied in 6 women in weeks 38-40 of pregnancy, among whom 5 were carriers of group B streptococci in urethra and/or cervix. The chlorhexidine concentrations varied between 25 and 200 mg/l during the first hour after washing in 5 of the 6 women, whereas one patient showed concentrations below 25 mg/l. With the ex

Geophysical gas monitoring using optical techniques: volcanoes, geothermal fields and mines

Optical spectroscopy provides powerful means for studying geophysical gas emissions. An extensive research program in this field has been performed by Swedish researchers in collaboration with European partners during the last 10 years, and a review of the activities and results is given. The techniques suitable for geophysical gas monitoring include the differential absorption lidar (DIAL), diffe

Hydrogen peroxide degradation by immobilized cells of alkaliphilic Bacillus halodurans

Whole cells of Bacillus halodurans LBK 261 were used as a source of catalase for degradation of hydrogen peroxide. The organism, B. halodurans grown at 55 degrees C and pH 10, yielded a maximum catalase activity of 275U g(-1) (wet wt.) cells. The catalase in the whole cells was active over a broad range of pH with a maximum at pH8-9. The enzyme was optimally active at 55 degrees C, but had low sta

Cerebral haemodynamic and electrocortical CO2 reactivity in pigs anaesthetized with fentanyl, nitrous oxide and pancuronium

Cerebral haemodynamic, metabolic and electrocortical reactivity to alterations in arterial CO2 tension (PaCO2) was assessed in seven mechanically ventilated juvenile pigs to test an experimental model designed for cerebral pharmacodynamic and pharmacokinetic studies. The animals were anaesthetized with fentanyl, nitrous oxide and pancuronium and sequentially normo- and hyperventilated over a 100-m

The meaning of having to live with cancer in old age.

Little is known about how older people with cancer experience their life situation. To increase the understanding of how illness is experienced in older people with cancer, the aim of this study was to investigate the meaning of living with cancer in old age. The hermeneutic phenomenological method as described by van Manen and referred to as 'phenomenology of praxis' was used. Ten persons (seven

Identification of protein expression signatures associated with Helicobacter pylori infection and gastric adenocarcinoma using recombinant antibody microarrays

Antibody microarray based technology is a powerful emerging tool in proteomics, target discovery, and differential analysis. Here, we report the first study where recombinant antibody fragments have been used to construct large scale antibody microarrays, composed of 127 different antibodies against mostly immunoregulatory antigens. The arrays were based on single framework recombinant antibody fr

Cytogenetic polyclonality in hematologic malignancies

The present study was undertaken to ascertain the frequency of cytogenetic polyclonality in various hematologic malignancies and to investigate whether morphologic subgroup, age, gender, or previous genotoxic exposure influences the incidence. Among 2,243 cytogenetically investigated hematologic malignancies, 10 acute myeloid leukemias (AML), 5 myelodysplastic syndromes (MDS), 2 acute lymphoblasti

Childhood malignancy and maternal diabetes or other auto-immune disease during pregnancy.

Among 4380 children born in 1987-1997 of women with a diagnosis of diabetes and alive at the age of one, 10 were registered in the Swedish Cancer Registry before the end of 1998. The odds ratio for having a childhood cancer after maternal diabetes, stratified for year of birth, maternal age, parity, multiple birth, and 500 g birth weight class was 2.25 (95%CI 1.22-4.15). Among 5842 children born d

Hematopoietic stem cells: the paradigmatic tissue-specific stem cell

The recent prospective isolation of a wide variety of somatically derived stem cells has affirmed the notion that homeostatic maintenance of most tissues and organs is mediated by tissue-specific stem and progenitor cells and fueled enthusiasm for the use of such cells in strategies aimed at repairing or replacing damaged, diseased, or genetically deficient tissues and organs. Hematopoietic stem c

Density of configurational states from first-principles calculations: The phase diagram of Al-Na surface alloys

The structural phases of AlxNa1-x surface alloys have been investigated theoretically and experimentally. We describe the system using a lattice gas Hamiltonian, determined from density functional theory together with Monte Carlo (MC) calculations. The obtained phase diagram reproduces the experiment on a quantitative level. From calculation of the (configurational) density of states by recently i

On the efficiency of antennas

The fundamental limits of the power efficiency of an antenna are explored. The antenna is confined in a sphere and all of the currents are assumed to run in a material with a conductivity that is a function of the radial coordinate. The analysis is based on the expansion of the electromagnetic fields in terms of vector spherical harmonics. Explicit expressions for the limits of efficiency are deri

Reporting leaders and followers among trajectories of moving point objects

Widespread availability of location aware devices (such as GPS receivers) promotes capture of detailed movement trajectories of people, animals, vehicles and other moving objects, opening new options for a better understanding of the processes involved. In this paper we investigate spatio-temporal movement patterns in large tracking data sets. We present a natural definition of the pattern 'one ob