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Relict silicate inclusions in extraterrestrial chromite and their use in the classification of fossil chondritic material

Chromite is the only common meteoritic mineral surviving long-term exposure on Earth, however, the present study of relict chromite from numerous Ordovician (470 Ma) fossil meteorites and micrometeorites from Sweden, reveals that when encapsulated in chromite, other minerals can survive for hundreds of millions of years maintaining their primary composition. The most common minerals identified, in

Evaluation of fluorescently labeled xylopyranosides as probes for proteoglycan biosynthesis

A new fluorescent analog to the antiproliferative 2-(6-hydroxynaphthyl)-beta-D-xylopyranoside has been synthesized and tested on a T24 cell line. The new analog was efficiently uptaken by the T24 cells but did not initiate priming of GAG chains. The results are similar to other fluorescently labeled analogs and we propose that these compounds are too large and unpolar to efficiently function as GA

Light scattering by selected zooplankton from the Gulf of Aqaba.

Light scattering by zooplankton was investigated as a major factor undermining transparency camouflage in these pelagic animals. Zooplankton of differing transparencies – including the hyperiid amphipod Anchylomera blossevillei, an unknown gammarid amphipod species, the brine shrimp Artemia salina, the euphausiid shrimp Euphausia diomedeae, the isopod Gnathia sp., the copepods Pontella karachiensi

Molecular basis for anaerobic growth of Saccharomyces cerevisiae on xylose, investigated by global gene expression and metabolic flux analysis

Yeast xylose metabolism is generally considered to be restricted to respirative conditions because the two-step oxidoreductase reactions from xylose to xylulose impose an anaerobic redox imbalance. We have recently developed, however, a Saccharomyces cerevisiae strain that is at present the only known yeast capable of anaerobic growth on xylose alone. Using transcriptome analysis of aerobic chemos

Expression of trkB in Human Neuroblastoma in Relation to MYCN Expression and Retinoic Acid Treatment.

Expression of full-length trkB can be found in some highly malignant neuroblastoma tumors with an amplified MYCN gene. This contrasts sympathetic neuroblasts, from which neuroblastomas are thought to arise, which neither express trkB nor are dependent on the p145trkB ligands, brain-derived neurotrophic factor (BDNF) or neurotrophin-4/5, for their normal development. In this study we show that trkB

Dynamics of water molecules in an alkaline environment

We report on a two-color mid-infrared pump-probe spectroscopic study of the dynamics of the OH stretch vibrations of HDO molecules dissolved in a concentrated (10 M) solution of NaOD in D2O. We observe that spectral holes can be created in the broad OH stretch absorption band that change neither position nor width on a picosecond time scale. This behavior differs strongly from that of pure HDO:D2O

Thrombomodulin as a Marker for Bleeding Complications During Warfarin Treatment

Background: The major adverse effect of warfarin treatment is hemorrhage. Several risk factors for bleeding complications are also risk factors for thromboembolic events, making the clinical decision to initiate or withhold anticoagulant treatment difficult. Specific markers that solely identify patients at high risk of bleeding would have great clinical impact. This study aimed to test if thrombo

Maximum likelihood estimation of a time-inhomogeneous stochastic differential model of glucose dynamics

Stochastic differential equations (SDEs) are assuming an important role in the definition of dynamical models allowing for explanation of internal variability (stochastic noise). SDE models are well established in many fields, such as investment finance, population dynamics, polymer dynamics, hydrology and neuronal models. The metabolism of glucose and insulin has not yet received much attention f

Line Identifications in the Spectrum of eta Carinae as Observed in 1990-1991 with CCD Detectors

We have used the Cerro Tololo Inter-American Observatory telescopes andspectrographs to record emission lines in eta Carinae from 3093 to8956 Å with a gap between 4432 and 5696 Å. A resolving powerof about 20,000 was used throughout. Accurate wavelengths, peakintensities relative to the local continuum, and line identificationsare presented. The data are briefly discussed with respect to the state

Desensitization of acetylcholine induced inositol 1,4,5-trisphosphate formation in neuroblastoma SH-SY5Y cells following repetitive acetylcholine stimulations

In this study, the desensitization of acetylcholine-induced inositol 1,4,5-trisphosphate [I(1,4,5)P3] formation, upon short-time prestimulations, was investigated in cultures of human neuroblastoma SH-SY5Y cells. Four repeated stimulations for 10 seconds with 10 microM acetylcholine were necessary to induce a desensitization of the I(1,4,5)P3 formation. The desensitization was observed 4 hours aft

Dissecting the mechanical unfolding of ubiquitin

The unfolding behavior of ubiquitin under the influence of a stretching force recently was investigated experimentally by single-molecule constant-force methods. Many observed unfolding traces had a simple two-state character, whereas others showed clear evidence of intermediate states. Here, we use Monte Carlo simulations to investigate the force-induced unfolding of ubiquitin at the atomic level

Deep-seated ordinary and atypical lipomas - Histopathology, cytogenetics, clinical features, and outcome in 215 tumours of the extremity and trunk wall

Deep-seated lipomas are often atypical histologically and are considered by some to have a high risk of recurrence after excision. We reviewed 215 deep-seated lipomas of the extremities and trunk wall with reference to histology, cytogenetics, clinical features and local recurrence. We classified tumours with atypical features and/or ring chromosomes as atypical lipomas. These were more common in

Effects of different fertilizer treatments on ectomycorrhizal colonization potential in 2 Scots pine forests in Sweden

Ectomycorrhizal fungal colonization potential was studied in two low-productivity Scots pine (Pinus sylvestris L.) forests in Sweden treated with different fertilizers. Young Pinus sylvestris seedlings were used as baits for ectomycorrhizal fungi for one growing season and the total ectomycorrhizal colonization level and frequencies of different types were recorded. One of the experimental sites h

Effects of thermal degradation products from polyurethane foams based on toluene diisocyanate and diphenylmethane diisocyanate on isolated, perfused lung of guinea pig

Objectives The composition of thermal degradation products from two types of polyurethane foams, one based on toluene diisocyanate (TDI) and the other on diphenylmethane diisocyanate (MDI), was analyzed and their toxic lung effects were compared. Methods Isolated perfused lungs of guinea pig were subjected to thermal decomposition products of polyurethane foams from an aerosol generator with compa

Age affects proximal brachial artery stiffness; Differential behavior within the length of the brachial artery?

With increasing age, the diameter of central elastic arteries increases, whereas their distensibility decreases. The purpose of this study was to investigate the mechanical properties of the proximal brachial artery in relation to age and gender. Distensibility coefficient (DC), stiffness and compliance coefficient (CC) were calculated in 136 healthy males and females (range 9-82 y) using echo-tra

Transgenic rescue demonstrates involvement of the Ian5 gene in T cell development in the rat.

A single point mutation in a novel immune-associated nucleotide gene 5 (Ian5) coincides with severe T cell lymphopenia in BB rats. We used a transgenic rescue approach in lymphopenic BB-derived congenic F344.lyp/lyp rats to determine whether this mutation is responsible for lymphopenia and to establish the functional importance of this novel gene. A 150-kb P1 artificial chromosome (PAC) transgene