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Gene expression changes in the course of neural progenitor cell differentiation

The molecular changes underlying neural progenitor differentiation are essentially unknown. We applied cDNA microarrays with 13,627 clones to measure dynamic gene expression changes during the in vitro differentiation of neural progenitor cells that were isolated from the subventricular zone of postnatal day 7 mice and grown in vitro as neurospheres. In two experimental series in which we withdrew

On the temporal contrast of high intensity femtosecond laser pulses

The temporal contrast is classified into two main regimes, the nanosecond-scale and the picosecond-scale contrast prior to the main pulse. The Lund terawatt laser system is shown to be improved on the nano- and picosecond-scale by a factor of 10 and 50, respectively, when it was optimized for contrast but not for energy. Calculations are also presented to emphasize the role of angular dispersion o

Pump-probe lifetime measurements on singlet ungerade states in molecular nitrogen

Excited-state lifetimes for a number of vibronic states of (1)Pi(u) symmetry in molecular nitrogen have been determined experimentally in a laser-based pump-probe scheme using a coherent and tunable extreme ultraviolet source based on harmonic generation. States investigated in N-14(2) were b(1)Pi(u)(v = 6-9), of valence character, and c(3)(1)Pi(u)(v = 1) and o(3)(1)Pi(u)(v = 1), of Rydberg charac

Agarose-coated anion exchanger prevents cell-adsorbent interactions

A common problem during recovery of bioproducts by adsorption from particulate broths is fouling of the adsorbent material as a result of the interaction of cells and cell debris, which present negative charges, with the positively charged anion exchangers commonly used in bioprocesses. The effect of shielding an adsorbent with a layer of agarose on reducing the binding of cells while still allowi

Fria radikaler och sjuka proteiner - bovarna bakom Parkinsons sjukdom?[Free radicals and ailing proteins - the culprits behind Parkinson’s disease?]

Parkinson’s disease is one of the most common neurodegenerative diseases, and affects approximately 1% of the population over 65 years of age. Many different insults appear to be involved in the etiology of the disease, among them environmental toxins and mitochondrial dysfunction. During the past five years, mutations in five different genes have been linked to rare, familial forms of Parkinson’s

Changes in tissue optical properties due to radio-frequency ablation of myocardium

The optical properties of pig heart tissue were measured after in vivo ablation therapy had been performed during open-heart surgery. In vitro samples of normal and ablated tissue were subjected to measurements with an optically integrating sphere set-up in the region 470-900nm. Three independent measurements were made: total transmittance, total reflectance and collimated transmittance, which mad

Assessing the use of retrospective databases in conducting economic evaluations of drugs : the case of asthma

When evaluating drug substances, the traditional clinical study setting does not allow scope for observing real-life behaviour since all alternative actions are determined beforehand. However, a study based on prospective or retrospective databases containing real-life data can examine how patients and physicians behave in a real-world setting and can investigate the relationship between the intro

Evolution of multi-stage dormancy in temporally autocorrelated environments.

Question: Under what circumstances does a capacity for multi-stage dormancy (i.e. dormancy in more than one life-stage) evolve? Mathematical methods: Optimization in stochastic environments. Results are derived both analytically and by simulations. Key assumption: There exists some trade-off between resources allocated to reproduction and adult dormant survival. Different shapes of this trade-off

Low expression of fragile histidine triad gene correlates with high proliferation in head and neck squamous cell carcinoma

Frequent loss of heterozygosity in head and neck squamous cell carcinoma (HNSCC) has been found in several chromosomal regions such as 3p, 9p, 11q, 13q and 17p. Fragile histidine triad (FHIT) gene is located at 3p14.2 encompassing a common fragile site, and is identified as a tumor suppressor gene. We examined 57 patients with HNSCC using immunohistochemistry, western blot, and reverse transcripta

A method for contextual inquiry: some reflections

This paper is the third in a series which recounts experiences in a project conducted in a newly-created Department of the University of Portsmouth (see also Bednar et al, 2004 and Eglin et al, 2005). A variant of the Strategic Systemic Thinking (SST) Framework (Bednar, 2000) was used to support the 25 staff of the Department to explore possibilities for development in a range of areas of work rel

Chaotic electrical activity of living beta-cells in the mouse pancreatic islet

To test for chaotic dynamics of the insulin producing beta-cell and explore its biological role, we observed the action potentials with the perforated patch clamp technique, for isolated cells as well as for intact cells of the mouse pancreatic islet. The time series obtained were analyzed using nonlinear diagnostic algorithms associated with the surrogate method. The isolated cells exhibited shor