bluuebunny/crossref_metadata_2025_split huggingface dataset:
Supramolecular Assembly of a 2D Binary Network of Pentacene and Phthalocyanine on Cu(100)
Authors: Krauss Tobias N. , Barrena Esther , Dosch Helmut , Wakayama Yutaka 
Published: August 2009

AbstractA crystalline nanoporous molecular network was tailored by supramolecular assembly of pentacene and F16CuPc on Cu(100). The structure and self‐assembly mechanisms of the pure and binary layers were analyzed by STM. F16CuPc films and mixed layers of pentacene/F16CuPc in a ratio of 2:1 show two enantiomorphic chiral domains with high structural order in contrast to pentacene which exhibits no long‐range order in pure films. A model of the epitaxial relationship on Cu(100) is given, which suggests CF⋅⋅⋅H bonding as a possible driving force for the bimolecular self‐assembly in addition to the still strong interaction between the substrate and the organic bilayer.
Obesity predisposes to Th17 bias
Authors: Winer Shawn , Paltser Geoff , Chan Yin , Tsui Hubert , Engleman Edgar , Winer Daniel , Dosch H.‐Michael 
Published: August 2009

AbstractObesity is associated with numerous inflammatory conditions including atherosclerosis, autoimmune disease and cancer. Although the precise mechanisms are unknown, obesity‐associated rises in TNF‐α, IL‐6 and TGF‐β are believed to contribute. Here we demonstrate that obesity selectively promotes an expansion of the Th17 T‐cell sublineage, a subset with prominent pro‐inflammatory roles. T‐cells from diet‐induced obese mice expand Th17 cell pools and produce progressively more IL‐17 than lean littermates in an IL‐6‐dependent process. The increased Th17 bias was associated with more pronounced autoimmune disease as confirmed in two disease models, EAE and trinitrobenzene sulfonic acid colitis. In both, diet‐induced obese mice developed more severe early disease and histopathology with increased IL‐17+ T‐cell pools in target tissues. The well‐described association of obesity with inflammatory and autoimmune disease is mechanistically linked to a Th17 bias.
A possible contribution of retinoids to regulation of fetal B lymphopoiesis
Authors: Chen Xinrong , Welner Robert S. , Kincade Paul W. 
Published: August 2009

AbstractWe recently found that all trans retinoic acid (ATRA) accelerated B lymphocyte formation. In the current study, we address the question whether retinoids account for the rapid lymphopoiesis that is characteristic of fetal progenitors. Surprisingly, addition of ATRA to fetal liver cultures actually reduced B lymphopoiesis. A pan‐retinoid receptor antagonist selectively suppressed lymphocyte formation from fetal and adult progenitors, suggesting some normal contribution of retinoids to this process. Consistent with this role, B lymphopoiesis was compromised in the marrow of mice with prolonged vitamin A deficiency. Recently identified B1 progenitors from adult marrow were similar to adult B2 progenitors in that their differentiation was stimulated by ATRA. The inhibitory response observed with fetal cells was seen when adult progenitors were exposed to high doses in culture or when adult mice were treated with ATRA for 2 wk. In addition to explosive lymphocyte generation, fetal progenitors tend to be less IL‐7 dependent than their adult counterparts, but ATRA did not make fetal progenitors IL‐7 independent. We conclude that all known categories of B lineage progenitors are responsive to retinoids and probably regulated by these compounds under physiological conditions. Retinoids may account in part for rapid differentiation in fetal life, but not all unique features of fetal progenitors.
Dynamics of peripheral tolerance and immune regulation mediated by Treg
Authors: Sakaguchi Shimon , Wing Kajsa , Yamaguchi Tomoyuki 
Published: August 2009

AbstractPeripheral self‐tolerance and immune homeostasis are maintained, at least in part, by the balance between Treg and effector T cells. Naturally, arising CD25+CD4+ Treg, which express the transcription factor Foxp3, suppress the activation and proliferation of other lymphocytes in multiple ways. A CTLA‐4‐dependent suppressive mechanism is shared by every Foxp3+ Treg at any location and its disruption breaches self‐tolerance and immune homeostasis, suggesting that it is a core mechanism of suppression. Depending on the environment, Foxp3+ Treg also differentiate to exhibit additional suppressive mechanisms, including the secretion of immunosuppressive cytokines. Naïve T cells acquire Foxp3 expression and suppressive activity under certain in vivo and in vitro conditions, whereas some Foxp3+ T cells may lose Foxp3 and suppressive activity following proliferation in an IL‐2‐deficient environment. Moreover, activated effector T cells frequently secrete suppressive cytokines, such as IL‐10, in a negative feedback fashion. These findings, when taken together, indicate that peripheral immune tolerance and homeostasis are dynamically maintained by functional differentiation within the Foxp3+ population, occasional conversion between Treg and non‐Treg cells, and the interactions among them. These dynamics provide ample opportunities for immune intervention for the benefit of the host.
Improvement of Staphylococcus xylosus lipase production through optimization of the culture conditions
Authors: Ghribi Dhouha , Sayari Adel , Gargouri Youssef , Bezzine Sofiane 
Published: August 2009

AbstractThe Staphylococcus xylosus strain produces without induction an original lipase named S. xylosus lipase (SXL). Since considerable interest has been given to microbial lipases for biotechnology applications like detergents, food, drugs and pharmaceutical products, improvement of their production is of great importance to reduce the final cost. This goal could be reached through the optimization of several physicochemical culture conditions. Indeed, an appropriate medium was formulated for SXL production. It was composed of 17 g/L pancreatic digest of casein, 2.5 g/L glucose, 6 g/L yeast extract, 0.75 g/L ammonium sulfate corresponding to a C/N ratio of 6, 1 g/L K2HPO4 and 1 g/L KH2PO4. In such a medium, SXL production reached 42 U/mL. Moreover, the usefulness of such a medium for large‐scale production of SXL was also evidenced in an automated fully controlled 2.6‐L fermenter. It was shown that aeration of the medium, which strongly affected the growth, regulated the lipase synthesis by the produced cells. It was found that when using a dissolved oxygen saturation of the medium of 50%, the SXL production reached 62 U/mL.
Convergent Synthesis of Pancratistatin from Piperonal and Xylose
Authors: Dam Johan Hygum , Madsen Robert 
Published: August 2009

AbstractA synthesis of the antitumour agent pancratistatin is described from piperonal and D‐xylose. Piperonal is converted into cinnamyl bromide 11 while methyl 5‐iodoribofuranoside 12 is derived from xylose. The allylic bromide and the iodocarbohydrate are combined in a zinc‐mediated tandem reaction to afford a highly functionalised 1,7‐diene, which is then converted into the corresponding cyclohexene by ring‐closing olefin metathesis. Subsequent Overman rearrangement, dihydroxylation and deprotection afford the natural product in a total of 25 steps from the two starting materials. The longest linear sequence is from piperonal and gives rise to pancratistatin in 18 steps and 7.0 % overall yield. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
On‐line solid phase extraction CZE for the simultaneous determination of lanthanum and gadolinium at picogram per liter levels
Authors: Vizioli Nora , Gil Raúl , Martínez Luis Dante , Fernanda Silva María 
Published: August 2009

AbstractA non‐specific on‐line method is presented for the extraction and preconcentration of two rare earth elements using a microcartridge containing C18‐derivatized silica particles prior to their analysis by CZE. The microcartridge, named analyte concentrator, was coupled on‐line to the inlet of the separation capillary (fused‐silica (FS) capillary, 75 μm id ×12 cm from the inlet to the microcartidge and 37 cm from the microcartridge to the detector). The reversed‐phase sorbent quantitatively retained gadolinium (Gd) and lanthanum (La) as 2‐(5‐bromo‐2‐pyridylazo)‐5‐diethylaminophenol complexes in the presence of non‐ionic micelles of polyethylene glycol tert‐octylphenyl ether, enabling sample clean‐up and concentration enhancement with minimum sample handling. The rare earth elements chelates were released from the sorbent with methanol and then analyzed by CZE with diode array detection. A background electrolyte of 20 mM sodium tetraborate containing 8% ACN, pH 9.0, was found to be optimal for the separation of metal chelates. The concentration limits of detection were lowered to picogram per liter levels (20 pg/L for La and 80 pg/L for Gd). A 1000‐fold improvement in concentration sensitivity for La‐ and Gd‐2‐(5‐bromo‐2‐pyridylazo)‐5‐diethylaminophenol complexes with respect to CZE without preconcentration was reached.
Improved resolution in the acidic and basic region of 2‐DE of insect antennae proteins using hydroxyethyl disulfide
Authors: Acín Patricia , Rayó Josep , Guerrero Angel , Quero Carmen 
Published: August 2009

AbstractOlfaction is essential for processing chemical signals in insects, but characterizing the proteins implicated in this process has proved challenging. We optimized 2‐DE gel resolution of insect proteins by using a buffer containing two reducing agents, DTT and hydroxyethyl disulfide. This buffer clearly improved resolution and decreased spot streaking and spot trains of 2‐DE in comparison to DTT alone. We described for the first time that the buffer with DTT and hydroxyethyl disulfide further to reducing streaking in the basic part of the gel eliminates false spots in the acidic gel regions that appeared when only DTT was used as reducing agent.
Wavelet transform based decomposition and reconstruction for on‐line PD detection and measurement. Part I: Narrow band components decomposition
Authors: Haghjoo Farhad , Shahrtash S. Mohammad 
Published: August 2009

AbstractIn this paper, a novel multi‐resolution filter for on‐line decomposition and analysis of partial discharge (PD) signals based on discrete wavelet transform (DWT) is developed. By applying this filter, as soon as a new sample of the original signal is drawn, the new elements of detail and approximate components at any desired level is derived, and the successive procedure of signal processing in basic DWT is eliminated. Using this filter, the PD or any non‐stationary (transient) signal is decomposed to different frequency band components, simultaneously. Therefore, the decomposition components of PD signals in all frequency bandwidths are simultaneously available. The frequency characteristic of this filter is verified, then in order to make the proposed filter more suitable for on‐line applications, its order is reduced without losing the accuracy of the results. Results, for simulation and field test data, have shown the appropriateness of the proposed filter for on‐line PD detection and measurement. Copyright © 2009 John Wiley & Sons, Ltd.
Sub‐Freezing Conductivity of PFSA Membranes
Authors: Álvarez‐Gallego Y. , de Heer M. P. 
Published: August 2009

AbstractSome properties of perfluorosulphonic acid (PFSA) membranes at sub‐freezing temperatures are presented in this work. Both commercial PFSAs and PFSA‐based membranes, developed within the Autobrane project, have been investigated. The proton conductivity at temperatures between –25 and 0 °C, has been determined by AC Impedance Spectroscopy. At each given condition, the different PFSA membranes exhibit similar values of proton conductivity. At –25 °C, the proton conductivities under ice‐saturated conditions were three to ten times higher than under reduced p conditions. As expected, proton conductivities decreased with decreasing temperature. The phase behaviour of water in the PFSA membranes has been investigated by differential scanning calorimetry (DSC) at temperatures between 20 and –60 °C. Water contents of membrane samples were estimated by thermo‐gravimetrical analysis (TGA) before the measurement (in fully hydrated state) and after measurement at –25 °C. For all the membranes, there was a remarkable decrease in the hydration number after the experiment at –25 °C. This fact may also contribute to the decrease in conductivity observed. No evidence of damage as a consequence of the measuring conditions could be detected for any of the membranes.
Dissecting structure–function interactions in acute optic neuritis to investigate neuroplasticity
Authors: Jenkins Thomas , Ciccarelli Olga , Toosy Ahmed , Miszkiel Katherine , Wheeler‐Kingshott Claudia , Altmann Daniel , Mancini Laura , Jones Steve , Plant Gordon , Miller David , Thompson Alan 
Published: August 2009

AbstractStructural MRI, electrophysiology, and functional MRI (fMRI) elucidate different aspects of damage and repair in demyelinating diseases. We combined them to investigate why patients with optic neuritis (ON) exhibit a wide variation in severity of acute visual loss, with the following objectives: (1) To determine how structural and electrophysiological changes in the anterior and posterior visual pathways contribute to acute visual loss. (2) To combine these data with fMRI, to investigate whether cortical activity modulates visual acuity. The visual system of 28 patients with acute unilateral ON was assessed. Linear regression modeling was used to identify parameters associated with acute visual loss, and to determine whether fMRI activity was associated with vision, after accounting for structural and electrophysiological predictors, age, and gender. Optic nerve lesion length and visual evoked potential (VEP) amplitude were associated with visual loss. Bilateral activation in the extra‐striate occipital cortex correlated directly with vision, after adjusting for optic nerve lesion length, VEP amplitude, and demographic characteristics. These data suggest that acute visual loss is associated with the extent of inflammation and conduction block in the optic nerve, but not with pathology in the optic radiations or occipital cortex. The association of better vision with greater fMRI responses, after accounting for factors which reduce afferent input, suggests a role for adaptive neuroplasticity within the association cortex of the dorsal stream of higher visual processing. Longitudinal studies will clarify whether different extra‐striate cortical regions play a role in adaptive plasticity in the acute and chronic stages of injury. Hum Brain Mapp, 2010. © 2009 Wiley‐Liss, Inc.
Age‐related differences in multiple measures of white matter integrity: A diffusion tensor imaging study of healthy aging
Authors: Bennett Ilana J. , Madden David J. , Vaidya Chandan J. , Howard Darlene V. , Howard James H. 
Published: August 2009

AbstractDiffusion tensor imaging (DTI) measures diffusion of molecular water, which can be used to calculate indices of white matter integrity. Early DTI studies of aging primarily focused on two global measures of integrity; the average rate (mean diffusivity, MD) and orientation coherence (fractional anisotropy, FA) of diffusion. More recent studies have added measures of water movement parallel (axial diffusivity, AD) and perpendicular (radial diffusivity, RD) to the primary diffusion direction, which are thought to reflect the neural bases of age differences in diffusion (i.e., axonal shrinkage and demyelination, respectively). In this study, patterns of age differences in white matter integrity were assessed by comparing younger and healthy older adults on multiple measures of integrity (FA, AD, and RD). Results revealed two commonly reported patterns (Radial Increase Only and Radial/Axial Increase), and one relatively novel pattern (Radial Increase/Axial Decrease) that varied by brain region and may reflect differential aging of microstructural (e.g., degree of myelination) and macrostructural (e.g., coherence of fiber orientation) properties of white matter. In addition, larger age differences in FA in frontal white matter were consistent with the anterior–posterior gradient of age differences in white matter integrity. Together, these findings complement other recent studies in providing information about patterns of diffusivity that are characteristic of healthy aging. Hum Brain Mapp, 2010. © 2009 Wiley‐Liss, Inc.
Seasonality of epCO2 at different scales along an integrated river continuum within the Dee basin, NE Scotland
Authors: Dawson Julian J.C. , Soulsby Chris , Hrachowitz Markus , Speed Mark , Tetzlaff Doerthe 
Published: August 2009

AbstractSpatial and temporal variations of free CO2 concentrations in surface waters are mainly controlled by dynamic processes encompassing terrestrial inputs and in‐stream biotic cycling. Free CO2 can be expressed as ‘excess partial pressure of CO2’ (epCO2), indicating supersaturation or under‐saturation with respect to atmospheric CO2. Seasonal patterns of epCO2 at sites draining nested upland catchments between 3·40 and 1837 km2 were assessed within the River Dee basin in NE Scotland. EpCO2 values ranged from 0·14 at the lowermost site on the mainstem in autumn to 12·7 on a major tributary during spring.A seasonality index was derived to describe contrasting winter/spring maxima and summer/autumn minima as annual mean epCO2 values could not clearly distinguish between different sites. Seasonal differences tended to increase downstream as progressive changes in physicochemical conditions enhanced the influence of autotrophic communities. However, perturbations to this continuum occurred as CO2 inputs from high DOC, heterotrophic tributaries and land‐use changes between open moorland and forest affected downstream continuity. Major tributaries showed reduced differences between seasons compared to the mainstem. Smaller headwaters indicated a lack of seasonality as high connectivity of responsive, peaty soils enabled continual inputs of terrestrially derived free CO2 to streams concomitant with limited autotrophic CO2 removal, maintaining epCO2 > 1 throughout.Seasonality of epCO2 was mainly driven by the ability of in‐stream biota to consume CO2 during optimal conditions in summer/autumn. This was confirmed by multiple linear regression analysis, which indicated that, apart from catchment area, baseflow and biotic activity indicators were the best predictors of epCO2 seasonality characteristics at any particular stage of the river system. Copyright © 2009 John Wiley & Sons, Ltd.
Versican overexpression in human breast cancer lesions: Known and new isoforms for stromal tumor targeting
Authors: Kischel Philippe , Waltregny David , Dumont Bruno , Turtoi Andrei , Greffe Yannick , Kirsch Stephanie , De Pauw Edwin , Castronovo Vincent 
Published: August 2009

AbstractProteoglycans play a key role in cancer development and progression by participating in the constitution of a specific fertile tumor microenvironment. As they are largely overexpressed in the malignant stroma, proteoglycans provide a reservoir of potential new targets for anticancer therapies, because they can serve to convey toxic payloads in the close proximity of cancer cells and subsequently destroy them. In this context, versican, a proteoglycan largely overexpressed in several solid cancers, bears the potential to be such an ideal target. As 4 main versican isoforms have been characterized, we sought to determine which isoform could represent the best target in human breast cancer. We used a series of 10 primary breast cancer lesions that were characterized as overexpressing the versican protein, when compared with matched normal breast tissues, using shotgun mass spectrometry and immunohistochemistry experiments. Quantitative polymerase chain reaction and western‐blotting experiments were used to evaluate versican isoform expression in breast cancer/normal tissue pairs for which ARN quality was excellent. All known isoforms were significantly overexpressed in the malignant lesions, both at the mRNA and at the protein levels. In the course of this study, we also identified and cloned a new alternatively spliced versican isoform, referred to as V4, which was also found to be upregulated in human breast cancer. This study provides for the first time a comprehensive mRNA and protein analysis of versican isoforms expression in human breast tissues, and offers insights into which therapeutic strategy would be best suited to target versican in human breast cancer lesions.
Cytotoxic effects of antipsychotic drugs implicate cholesterol homeostasis as a novel chemotherapeutic target
Authors: Wiklund Erik D. , Catts Vibeke S. , Catts Stanley V. , Ng Teng Fong , Whitaker Noel J. , Brown Andrew J. , Lutze‐Mann Louise H. 
Published: August 2009

AbstractThe reported reduction in cancer risk in those suffering from schizophrenia may be because antipsychotic medications have antineoplastic effects. In this study, 6 antipsychotic agents with a range of structural and pharmacological properties (reserpine, chlorpromazine, haloperidol, pimozide, risperidone and olanzapine), were screened for their effect on the viability of cell lines derived from lymphoblastoma, neuroblastoma, non‐small cell lung cancer and breast adenocarcinoma. We aimed to determine if antipsychotic drugs in general possess cancer‐specific cytotoxic potential, and whether it can be attributed to a common mode of action. With the exception of risperidone, all drugs tested displayed selective inhibition of the viability of cancer cell lines compared with normal cells. Using Affymetrix expression microarrays and quantitative real‐time polymerase chain reaction, we found that for the antipsychotic drugs, olanzapine and pimozide, cytotoxicity appeared to be mediated via effects on cholesterol homeostasis. The role of cholesterol metabolism in the selective cytotoxicity of these drugs was supported by demonstration of their increased lethality when coadministered with a cholesterol synthesis inhibitor, mevastatin. Also, pimozide and olanzapine showed accelerating cytotoxic effects from 12 to 48 hr in time course studies, mirroring the time‐dependent onset of cytotoxicity induced by the amphiphile, U18666A. On the basis of these results, we concluded that the Class II cationic amphiphilic properties of antipsychotic drugs contribute to their cytotoxic effects by acting on cholesterol homeostasis and altering the biophysical properties of cellular membranes, and that drugs affecting membrane‐related cholesterol pathways warrant further investigation as potential augmentors of standard cancer chemotherapy.