julilili42/papers huggingface dataset:
Upregulation of frizzled 9 in astrocytomas
2006-11-02

Wnt/frizzled (FZD) cascades play important roles in controlling cell fate, proliferation, migration, tissue architecture and organogenesis during embryonic development and in adult organisms. The potential involvement of this pathway in tumorigenesis has been established in several types of cancers. Frizzled 9 (FZD9) is expressed in brain and its aberrant expression in gastric cancer was observed. However, its association with astrocytomas remains unknown therefore we studied FZD9 expression in astrocytomas of different malignancy. In the present study, FZD9 expression in 25 astrocytomas was investigated using immunohistochemistry with specific antibodies. Further FZD9 expression in native human brain tissue and glioblastoma cell line were analysed using real‐time reverse transcription polymerase chain reaction (RT‐PCR). In human astrocytomas, FZD9 immunoreactivity (IR) was observed in both microvessels and neoplastic cells. The percentage of FZD9 + microvessels in relation to FZD9 + vessels was significantly higher in malignant astrocytomas than in low‐grade astrocytomas and positively correlated with the astrocytoma World Health Organization (WHO) grading ( r = 1, P = 0.04). Furthermore, the FZD9 IR scores positively correlated with astrocytoma WHO grading ( r = 1, P = 0.04) and proliferating activity ( r = 0.77, P &lt; 0.001). Real‐time RT‐PCR data showed that FZD9 expression in human glioblastoma was significant higher than in normal brain ( P &lt; 0.05) but FZD9 expression was only slightly induced in cobalt chloride‐treated human glioblastoma T98G cells compared with untreated cells ( P &gt; 0.05). FZD9 is upregulated in astrocytomas, suggesting that FZD9 could be important in the tumorigenesis of human astrocytomas.
INTEGRAL observation of the accreting pulsar GX 1+4
2006-11-03

Aims. We present the results of the INTEGRAL monitoring campaign on the accreting low mass X-ray binary pulsar GX 1+4 performed during the Galactic plane scan of the INTEGRAL Core Programme.&#13;\\nMethods. The source was observed in different luminosity states ranging from L20−40 keV = 1.7 × 10−10 erg cm−2 s−1, to L20−40 keV = 10.5 × 10−10 erg cm−2 s−1 for about 779 ks from March 2003 until October 2004.&#13;\\nResults. Our observations confirm the secular spin down of GX 1+4 with the spin period (Ps) varying from 139.63 s to 141.56 s. In the highest luminosity state, a spin-up phase is observed. The phase-averaged spectrum of the source was modelled either with an absorbed cut-off power law or with a Comptonization model with significantly different parameters in the two brightest luminosity&#13;\\nstates. No evidence of any absorption-like feature is observed in the phase averaged spectrum up to 110 keV. At highest luminosity, the source is found to pulsate up to 130 keV. Phase resolved spectroscopy reveals a phase-dependent continuum and marginal evidence for&#13;\\nan absorption feature at 34 ± 2 keV in the descending part of the pulse. If interpreted as due to electron resonant cyclotron scattering, the magnetic field in the emitting region would be (2.9 ± 0.2) × 1012(1 + z)G where z is the gravitational red shift of the emitting region. We also observed a very low luminosity state, typical of this source, which lasted for about two days during which the source spectrum was modelled by a simple power law, and a pulsed signal was still detectable in the 15−100 keV energy range.
MALDI-TOF Mass Spectrometry for Multiplex Genotyping of CYP2B6 Single-Nucleotide Polymorphisms
2006-11-03

Abstract Background: CYP2B6 is a highly variable and polymorphic cytochrome P450 (CYP) enzyme involved in the biotransformation of an increasing number of drugs, including cyclophosphamide, bupropion, and the nonnucleosidic reverse transcriptase inhibitor efavirenz. Several nonsynonymous and promoter single-nucleotide polymorphisms (SNPs) in the CYP2B6 gene are associated with altered hepatic expression and function, which affect drug plasma concentrations. Methods: We used multiplex PCR to amplify relevant gene fragments while avoiding amplification of the CYP2B7P1 pseudogene. Polymorphic sites were analyzed by allele-specific primer extension followed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Method evaluation was performed on a panel of 287 genomic DNA samples previously genotyped by other methods. Results: Five multiplex assays were developed, comprising the following 15 SNPs: −82T→C (*22); 86G→C (R29T, *17); 136A→G (M46V, *11); 296G→A (G99E, *12); 415A→G (K139E, *8, *13); 419G→A (R140Q, *14); 516G→T (Q172H, *6, *7, *9, *13, *19, *20), 547G→A (V183I); 769G→A (D257N); 785A→G (K262R, *4, *6, *7, *13, *16, *19, *20); 983T→C (I328T, *16, *18); 1006C→T (R336C, *19); 1172T→A (I391N, *15); 1282C→A (P428T, *21); 1459C→T (R487C, *5, *7). In 9 DNA samples showing discrepant genotypes, correctness of the MALDI-TOF MS result was confirmed by direct sequencing. Conclusions: This genotyping method enabled sensitive, specific, accurate, and comprehensive determination of 15 relevant SNPs of CYP2B6. The assay design allows analysis of SNP subsets, incorporation of additional SNPs, and performance of high-throughput genotyping.
Synthesis of Benzomorphan Analogues by Intramolecular Buchwald–Hartwig Cyclization
2006-11-03

Abstract A new strategy toward the important class of benzomorphans is described. The key bond formation is based on an intramolecular Buchwald–Hartwig enolate arylation reaction. Thus, alkylation of piperidones with ortho ‐bromobenzyl bromides provides the necessary substrates. In the presence of a palladium catalyst, a sterically hindered phosphane ligand, and a base, carbon–carbon bond formation to tricyclic benzomorphan derivatives takes place. After removal of the N ‐protecting group, derivatization reactions are possible. (© Wiley‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2007)
On a Class of Non-Regenerative Sampling Distributions
2006-11-03

We show that the sampling formula induced from a Λ-coalescent process with multiple collisions is regenerative if and only if the measure Λ is either concentrated in 0 (Kingman case) or concentrated in 1 (star-shaped case). The Ewens sampling formula is the only sampling formula in this class which also belongs to Pitman's two-parameter family of sampling distributions.
Molecular Basis of Cervical Neoplasia
2006-11-03

10.1002/9781444312744.ch19.abs This chapter contains sections titled: Introduction Classification of Papillomaviruses Structure of the HPV Genome Replication Cycle in the Infected Epithelium Cervical Neoplasia: Transient Versus Persistent Infections Viral and Host Risk Factors Summary Acknowledgement References
Annotation: Neurofeedback – train your brain to train behaviour
2006-11-06

Background: Neurofeedback (NF) is a form of behavioural training aimed at developing skills for self‐regulation of brain activity. Within the past decade, several NF studies have been published that tend to overcome the methodological shortcomings of earlier studies. This annotation describes the methodical basis of NF and reviews the evidence base for its clinical efficacy and effectiveness in neuropsychiatric disorders. Methods: In NF training, self‐regulation of specific aspects of electrical brain activity is acquired by means of immediate feedback and positive reinforcement. In frequency training, activity in different EEG frequency bands has to be decreased or increased. Training of slow cortical potentials (SCPs) addresses the regulation of cortical excitability. Results: NF studies revealed paradigm‐specific effects on, e.g., attention and memory processes and performance improvements in real‐life conditions, in healthy subjects as well as in patients. In several studies it was shown that children with attention‐deficit hyperactivity disorder (ADHD) improved behavioural and cognitive variables after frequency (e.g., theta/beta) training or SCP training. Neurophysiological effects could also be measured. However, specific and unspecific training effects could not be disentangled in these studies. For drug‐resistant patients with epilepsy, significant and long‐lasting decreases of seizure frequency and intensity through SCP training were documented in a series of studies. For other child psychiatric disorders (e.g., tic disorders, anxiety, and autism) only preliminary investigations are available. Conclusions: There is growing evidence for NF as a valuable treatment module in neuropsychiatric disorders. Further, controlled studies are necessary to establish clinical efficacy and effectiveness and to learn more about the mechanisms underlying successful training.
Fast 3D radiofrequency field mapping using echo‐planar imaging
2006-11-06

Abstract An inhomogeneous radiofrequency (RF) magnetic field is an essential source of error for the quantification of MRI and MRS parameters. To correct for effects of RF inhomogeneities in 3D data sets, it is necessary to have knowledge of the 3D RF distribution in the sample. In this paper a method for fast 3D RF mapping is presented. The method is based on the simultaneous acquisition of a spin echo (SE) and a stimulated echo (STE) using echo‐planar imaging (EPI). The acquisition of the 3D RF map using 64 partitions and TR = 500 ms requires 1.5 min. The use of the sequence in vivo is demonstrated by the calculation of the RF maps in the human brain at 3T. The comparison of calculated flip angles with the flip angles obtained by fitting signal behavior in the 3D stimulated‐echo acquisition mode (STEAM)‐EPI sequence and the analysis of errors due to spatially dependent T 1 values in the brain show that the accuracy of the calculated flip angles in the human brain is about 2°. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Treatment of hereditary angioneurotic oedema (HANE) with tibolone
2006-11-07

Summary Objective Eight women, aged 25–58 years, with hereditary angioneurotic oedema (HANE) were treated with tibolone, a synthetic steroid exhibiting oestrogenic, androgenic and progestational activity. Design Pilot study. Results Tibolone at a dose of 2·5–7·5 mg/day significantly reduced the number and severity of attacks and the number of ampoules of C1‐esterase inhibitor (C1‐INH) needed for symptomatic therapy. The efficacy of tibolone was comparable to that of danazol, while the androgenic side‐effects were considerably reduced. Conclusions Tibolone may represent an alternative to danazol administration for the prophylaxis of HANE in women.
Biosynthetic Capacities of Actinomycetes. Part 37. Fluostatins C‐E, Novel Members of the Fluostatin Family Produced by Streptomyces Strain Acta 1383.
2006-11-07

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Alternative complex formation of the Ca2+‐regulated protein kinase CIPK1 controls abscisic acid‐dependent and independent stress responses in Arabidopsis
2006-11-08

Summary Intracellular release of calcium ions belongs to the earliest events in cellular stress perception. The molecular mechanisms integrating signals from different environmental cues and translating them into an optimized response are largely unknown. We report here the functional characterization of CIPK1, a protein kinase interacting strongly with the calcium sensors CBL1 and CBL9. Comparison of the expression patterns indicates that the three proteins execute their functions in the same tissues. Physical interaction of CIPK1 with CBL1 and CBL9 targets the kinase to the plasma membrane. We show that, similarly to loss of CBL9 function, mutation of either CBL1 or CIPK1 renders plants hypersensitive to osmotic stress. Remarkably, in contrast to the cbl1 mutant and similarly to the cbl9 mutant, loss of CIPK1 function impairs abscisic acid (ABA) responsiveness. We therefore suggest that, by alternative complex formation with either CBL1 or CBL9, the kinase CIPK1 represents a convergence point for ABA‐dependent and ABA‐independent stress responses. Based on our genetic, physiological and protein–protein interaction data, we propose a general model for information processing in calcium‐regulated signalling networks.
Concise Strategy to the Core Structure of the Macrolide Queenslandon
2006-11-08

The fully functionalized core structure of the macrolactone queenslandon was prepared using a novel strategy consisting of a glycolate aldol reaction and hydroboration of the derived enol ether 17 followed by Suzuki cross-coupling with an iodostyrene. After conversion of the cross-coupling product to the seco acid 22, Mitsunobu macrolactonization and protecting group manipulations led to the queenslandon model 5. [structure: see text]
Viscoelastic properties of individual glial cells and neurons in the CNS
2006-11-09

One hundred fifty years ago glial cells were discovered as a second, non-neuronal, cell type in the central nervous system. To ascribe a function to these new, enigmatic cells, it was suggested that they either glue the neurons together (the Greek word “γλια” means “glue”) or provide a robust scaffold for them (“support cells”). Although both speculations are still widely accepted, they would actually require quite different mechanical cell properties, and neither one has ever been confirmed experimentally. We investigated the biomechanics of CNS tissue and acutely isolated individual neurons and glial cells from mammalian brain (hippocampus) and retina. Scanning force microscopy, bulk rheology, and optically induced deformation were used to determine their viscoelastic characteristics. We found that ( i ) in all CNS cells the elastic behavior dominates over the viscous behavior, ( ii ) in distinct cell compartments, such as soma and cell processes, the mechanical properties differ, most likely because of the unequal local distribution of cell organelles, ( iii ) in comparison to most other eukaryotic cells, both neurons and glial cells are very soft (“rubber elastic”), and ( iv ) intriguingly, glial cells are even softer than their neighboring neurons. Our results indicate that glial cells can neither serve as structural support cells (as they are too soft) nor as glue (because restoring forces are dominant) for neurons. Nevertheless, from a structural perspective they might act as soft, compliant embedding for neurons, protecting them in case of mechanical trauma, and also as a soft substrate required for neurite growth and facilitating neuronal plasticity.
Synthesis of a Benzolactone Collection using Click Chemistry
2006-11-09

Abstract A collection of benzotriazoles consisting of seven compounds was prepared from the propynyl‐substituted benzolactone 1 and various azides using click chemistry. The lactone 1 was obtained through a short route by direct esterification of the allylbenzoic acid 9 with the alkynol 7 giving the benzoate 2 . The homopropargyl alcohol 7 in turn was obtained by opening the epoxide 6 with triisopropylsilyl acetylide. Ring‐closing metathesis of the ester 2 using Grubbs catalyst II followed by removal of the silicon protecting group furnished the lactone 1 . Two of the benzotriazoles, 17a and 17b , were also converted into the corresponding phenols to probe the role of the phenolic OH on the biological activity. All nine benzotriazoles showed cytotoxic activity in a L929 mouse fibroblast assay with IC 50 values in the low micromolar range. (© Wiley‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2007)
Temperature and age constraints on the metamorphism of the Tethyan Himalaya in Central Nepal: A multidisciplinary approach
2006-11-10

Metasediments of Devonian to Triassic age of the Tethyan Himalaya (TH) from several areas in central and western Nepal, between western Dolpo and Marsyandi Valley, were sampled for thermo-metamorphic studies (illite and chlorite "crystallinity", vitrinite reflectance, calcite-dolomite and chlorite-chloritoid geothermometers, K/Ar dating on illite-rich fractions and zircon fission track thermochronology). This paper reports, for the first time, the occurrence of chloritoid in the TH out of the range of granite contact aureoles. It also presents the first zircon fission track dating performed on TH metasediments. The peak temperatures of metamorphism have been around 250-300 degrees C, 320-350 degrees C, 330-370 degrees C and 400-450 degrees C in the western Dolpo, Hidden Valley, Manang and Marpha areas, respectively. In the Manang and Hidden Valley areas, illite K/Ar data are interpreted as ages, of recrystallized K-white micas newly formed during metamorphism at around 25-30 Ma. In the Marpha area, illite K/Ar and zircon fission-track ages (12-15 Ma) are consistent representing cooling ages after metamorphic overprinting of higher grade than in the other areas. The joint investigation of the organic maturation and zircon FT chronology yields insight on the thermal calibration of zircon reset. The R(max) of 5.7% to similar to 8.0% indicates a temperature range of ca. 315-325 degrees C which is in the partial annealing zone of the zircon FT thermochronometer. Our results might be explained by the presence of a thick thrust sheet once existing above the study area. (c) 2006 Elsevier Ltd. All rights reserved.
Exenatide in type 2 diabetes: treatment effects in clinical studies and animal study data
2006-11-10

The therapeutic options for treating type 2 diabetes have been widened by the introduction of exenatide as the first incretin mimetic. Incretins are gut hormones that contribute to the stimulation of insulin secretion after a carbohydrate rich meal. The incretin hormone glucagon-like peptide-1 (GLP-1) not only stimulates insulin secretion under hyperglycaemic conditions, but also suppresses glucagon secretion, slows gastric emptying, induces satiety and improves beta cell function in type 2 diabetes. These beneficial effects have awakened the interest to use GLP-1 for the treatment of type 2 diabetes. Because of its short biological half-life, GLP-1 itself is not practical for type 2 diabetes therapy. Exenatide is a peptide found in the lizard Heloderma suspectum and has a high similarity to GLP-1. Exenatide belongs to the novel class of incretin mimetics because of its incretin-like action. It has a much longer biological half life than GLP-1 and is a GLP-1 receptor agonist that can be used for therapeutic purposes by twice daily injection. Clinical studies and clinical experience with exenatide have shown a significant reduction in HbA1c, fasting- and postprandial glucose and a marked reduction in body weight in type 2 diabetic patients. Animal studies reveal an improvement of beta cell function and an increase in beta cell mass after exenatide treatment. This review gives an overview on exenatide, its pharmacological profile and its role and potential in the therapeutic setting of type 2 diabetes. Furthermore, future developments concerning exenatide application are highlighted.
Automatic data environment construction for static device drivers analysis
2006-11-10

Linux contains thousands of device drivers that are developed independently by many developers. Though each individual driver source code is relatively small---≈10k lines of code---the whole operating system contains a few million lines of code. Therefore Linux device drivers offer a useful application area for modular analysis.Our finding is that despite the precise modeling of most features of the standard systems programming language C, model checking software verification tools for C fail to provide means for modular analysis of device drivers. We inspected CBMC [2], SLAM-SDV [3], MAGIC [1], BLAST [4] and others and found that a rich additional environment model for every device driver is needed. This model must provide information on out-of-scope initialized pointers and complex data structures. We present strategies to automatically create feasible, bounded data environments for Linux device drivers instead of creating them manually. Our solution differs from general interface generation mechanisms (e.g. CUTE[5]), because is it specialised on bounded model checking of Linux device drivers written in C. Our contribution is a preprocessing step that extends the usability of CBMC for modular Linux device driver analysis.
Human Cytomegalovirus (HCMV) Infection of Endothelial Cells Promotes Naive Monocyte Extravasation and Transfer of Productive Virus To Enhance Hematogenous Dissemination of HCMV
2006-11-13

ABSTRACT Human cytomegalovirus (HCMV) pathogenesis is dependent on the hematogenous spread of the virus to host tissue. While data suggest that infected monocytes are required for viral dissemination from the blood to the host organs, infected endothelial cells are also thought to contribute to this key step in viral pathogenesis. We show here that HCMV infection of endothelial cells increased the recruitment and transendothelial migration of monocytes. Infection of endothelial cells promoted the increased surface expression of cell adhesion molecules (intercellular cell adhesion molecule 1, vascular cell adhesion molecule 1, E-selectin, and platelet endothelial cell adhesion molecule 1), which were necessary for the recruitment of naïve monocytes to the apical surface of the endothelium and for the migration of these monocytes through the endothelial cell layer. As a mechanism to account for the increased monocyte migration, we showed that HCMV infection of endothelial cells increased the permeability of the endothelium. The cellular changes contributing to the increased permeability and increased naïve monocyte transendothelial migration include the disruption of actin stress fiber formation and the decreased expression of lateral junction proteins (occludin and vascular endothelial cadherin). Finally, we showed that the migrating monocytes were productively infected with the virus, documenting that the virus was transferred to the migrating monocyte during passage through the lateral junctions. Together, our results provide evidence for an active role of the infected endothelium in HCMV dissemination and pathogenesis.
Sensory ecology of prey rustling sounds: acoustical features and their classification by wild Grey Mouse Lemurs
2006-11-13

1 Predatory mammals and birds from several phylogenetic lineages use prey rustling sounds to detect and locate prey. However, it is not known whether these rustling sounds convey information about the prey, such as its size or profitability, and whether predators use them to classify prey accordingly. 2 We recorded rustling sounds of insects in Madagascar walking on natural substrate and show a clear correlation between insect mass and several acoustic parameters. 3 In subsequent behavioural experiments in the field, we determined whether nocturnal animals, when foraging for insects, evaluate these parameters to classify their prey. We used field-experienced Grey Mouse Lemurs Microcebus murinus in short-term captivity. Mouse Lemurs are generally regarded as a good model for the most ancestral primate condition. They use multimodal sensorial information to find food (mainly fruit, gum, insect secretions and arthropods) in nightly forest. Acoustic cues play a role in detection of insect prey. 4 When presented with two simultaneous playbacks of rustling sounds, lemurs spontaneously chose the one higher above their hearing threshold, i.e. they used the rustling sound's amplitude for classification. We were not able, despite attempts in a reinforced paradigm, to persuade lemurs to use cues other than amplitude, e.g. frequency cues, for prey discrimination. 5 Our data suggests that Mouse Lemurs, when foraging for insects, use the mass–amplitude correlation of prey-generated rustling sounds to evaluate the average mass of insects and to guide their foraging decisions.