bluuebunny/crossref_metadata_2025 huggingface dataset:
The impact of pre‐ and/or probiotics on human colonic metabolism: Does it affect human health?
Authors: De Preter Vicky , Hamer Henrike M , Windey Karen , Verbeke Kristin
Published: November 2010

Since many years, the role of the colonic microbiota in maintaining the host's overall health and well‐being has been recognized. Dietary modulation of the microbiota composition and activity has been achieved by the use of pre‐, pro‐ and synbiotics. In this review, we will summarize the available evidence on the modification of bacterial metabolism by dietary intervention with pre‐, pro‐ and synbiotics. Enhanced production of SCFA as a marker of increased saccharolytic fermentation is well documented in animal andin vitrostudies. Decreased production of potentially toxic protein fermentation metabolites, such as sulfides, phenolic and indolic compounds, has been less frequently demonstrated. Besides, pre‐, pro‐ and synbiotics also affect other metabolic pathways such as the deconjugation of secondary bile acids, bacterial enzyme activities and mineral absorption. Data from human studies are less conclusive. The emergence of new analytical techniques such as metabolite profiling has revealed new pathways affected by dietary intervention. However, an important challenge for current and future research is to relate changes in bacterial metabolism to concrete health benefits. Potential targets and expected benefits have been identified: reduced risk for the metabolic syndrome and prevention of colorectal cancer.
Multiscale modeling of a sensitive marine clay
Authors: Yin Zhen‐Yu , Hattab Mahdia , Hicher Pierre‐Yves
Published: November 2010

This paper examines the mechanical behavior of a sensitive marine clay. Various laboratory tests on intact and reconstituted samples of Guinea Gulf marine clay were performed under isotropic compression and drained triaxial compression at constant confining stresses. Microstructure analysis on intact and reconstituted samples was also carried out under different loading conditions. The effect of inter‐aggregates bonding on mechanical properties is discussed. Based on experimental analysis, a new modeling method is proposed. In this approach, the clay is regarded as an assembly of aggregates of clay particles. An inter‐aggregate contact law is introduced relating contact forces to aggregates relative displacements. The deformation of the assembly can be obtained by integrating the movement of the inter‐aggregate contacts in all orientations. Thus, the effect of inter‐aggregates bonds and debonding is considered in a direct way. The model is evaluated through comparisons between the predicted and measured results on Guinea Gulf marine clay. The evolutions of local stresses, strains, and bonds in inter‐aggregates planes are discussed to explain the anisotropy induced by the applied loading. Copyright © 2010 John Wiley & Sons, Ltd.
Transplant‐associated thrombotic microangiopathy in pediatric patients treated with sirolimus and tacrolimus
Authors: Rosenthal Joseph , Pawlowska Anna , Bolotin Ellen , Cervantes Cheryl , Maroongroge Sean , Thomas Sandra H. , Forman Stephen J.
Published: November 2010

Background

Transplant‐associated thrombotic microangiopathy (TMA) syndromes are reported to occur with increased frequency in transplant patients treated with siroliumus combined with a calcineurin inhibitor. We performed a retrospective study of all pediatric transplant patients at City of Hope who were administered combined tacrolimus/sirolimus (TAC/SIR) to determine the occurrence of TMA.

Procedure

This analysis includes 41 consecutive patients between the ages of 2 and 20 (median age 9.1) who received an allogeneic hematopoietic stem cell transplant from any source and also received TAC/SIR for prevention or treatment of GVHD. Of those 41 patients, 20 received TAC/SIR as GVHD prohpylaxis and were designated the preventative group (PG), while 21 received TAC/SIR as treatment for GVHD and were designated the therapy group (TG). TMA occurrence in both groups was documented from day −1 of transplant to day 60 for the PG, and until 30 days after last dose for the TG. TMA was defined according to 2005 consensus criteria.

Results

Five of twenty patients in the PG, and five of twenty one in the TG, experienced TMA, with an overall rate of 23.8% for the population. All ten patients with TMA showed elevated levels of TAC, SIR or both and nine of ten suffered from organ injury due to regimen‐related toxicity or GVHD.

Conclusion

Physicians should exercise caution in the use of TAC/SIR in pediatric patients due to a high rate of TMA. It is not recommended for heavily pre‐treated patients and peak levels of TAC/SIR must be very carefully controlled. Pediatr Blood Cancer 2011;57:142–146. © 2010 Wiley‐Liss, Inc.
The NSN link as electron accepting moiety for stable, solution‐processable conjugated oligomers
Authors: Wang Mingfeng , Sun Yanming , Tong Minghong , Chesnut Eneida S. , Seo Jung Hua , Kumar Rajeev , Wudl Fred
Published: November 2010

New conjugated oligomers, oligo(9,9‐didodecylfluorene‐bis‐sulphurdiimide), consisting of 9,9‐didodecylfluorene separated by NSN moieties, are reported. These oligomers are stable purple solids under ambient conditions with absorption covering a broad spectral window in the UV‐vis range and a main broad peak centered at 555 nm with onset extending to 700 nm. These oligomers show an obviously longer conjugation length than its dimeric analogue, bis‐9,9‐didodecyl‐fluorene‐2‐sulfurdiimide that shows a band‐edge absorption centered at 484 nm with onset at 590 nm. The dimer and oligomers are soluble in a variety of organic solvents. Moreover, we found that the oligomer with an average repeating‐unit number of six could significantly quench the photoluminescence (PL) of poly[2‐methoxy‐5‐(2′‐ethyl‐hexyloxy)‐1,4‐phenylene vinylene] (MEH‐PPV) or poly(3‐hexylthiophene) (P3HT) in the solid state. More importantly, the composites of this oligomer with P3HT showed a nearly 10‐fold enhancement of the photocurrent, compared with that of P3HT itself. In addition, the PL of this oligomer could be quenched by the presence of phenyl‐C61‐butyric acid methyl ester (PCBM) in toluene. These results suggest the presence of photoinduced charge transfer in composites of these oligomers blended with an electronic partner that either donates or accepts electrons. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Synthesis and properties of multiblock copoly(arylene ether)s containing superacid groups for fuel cell membranes
Authors: Mikami Takefumi , Miyatake Kenji , Watanabe Masahiro
Published: November 2010

A series of block copoly(arylene ether)s containing pendant superacid groups were synthesized, and their properties were investigated for fuel cell applications. Two series of telechelic oligomers, iodo‐substituted oligo(arylene ether ketone)s and oligo(arylene ether sulfone)s, were synthesized. The degree of oligomerization and the end groups were controlled by changing the feed ratio of the monomers. The nucleophilic substitution polymerization of the two oligomers provided iodo‐substituted precursor block copolymers. The iodo groups were converted to perfluorosulfonic acid groups via the Ullmann coupling reaction. The high degree of perfluorosulfonation (up to 83%) was achieved by optimizing the reaction conditions. Tough and bendable membranes were prepared by solution casting. The ionomer membranes exhibited characteristic hydrophilic/hydrophobic phase separation with large hydrophilic clusters (ca. 10 nm), which were different from that of our previous random copolymers with similar molecular structure. The block copolymer structure was found to be effective in improving the proton‐conducting behavior of the superacid‐modified poly(arylene ether) ionomer membranes without increasing the ion exchange capacity (IEC). The highest proton conductivity was 0.13 S/cm at 80 °C, 90% relative humidity, for the block copolymer ionomer membrane with IEC = 1.29 mequiv/g. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Polymers for neural implants
Authors: Hassler Christina , Boretius Tim , Stieglitz Thomas
Published: November 2010

Neural implants are technical systems that restore sensory or motor functions after injury and modulate neural behavior in neuronal diseases. Neural interfaces or prostheses have lead to new therapeutic options and rehabilitation approaches in the last 40 years. The interface between the nervous tissue and the technical material is the place that determines success or failure of the neural implant. Recording of nerve signals and stimulation of nerve cells take place at this neuro‐technical interface. Polymers are the most common material class for substrate and insulation materials in combination with metals for interconnection wires and electrode sites. This work focuses on the neuro‐technical interface and summarizes its fundamental specifications first. The most common polymer materials are presented and described in detail. We conclude with an overview of the different applications and their specific designs with the accompanying manufacturing processes from precision mechanics, laser structuring and micromachining that are introduced in either the peripheral or central nervous system. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2010
Progress in low‐loss and high‐bandwidth plastic optical fibers
Authors: Koike Yasuhiro , Koike Kotaro
Published: November 2010

Plastic optical fibers (POFs) are highly promising transmission media for future home networking.In comparison to glass optical fibers (GOFs), which are commonly used in core and metropolitan networks, POFs offer many advantages such as great flexibility and easy handling. This review begins with the basic concepts of optical fibers and moves on to the early history of loss reduction in POFs. What drastically changed the status of POFs in the communications field was a graded‐index technology that improved the bandwidth to over 1 gigabits per second. However, even after the loss and bandwidth were enhanced to their limits, the performances of POFs were insufficient for market demand when using conventional optical polymer materials such as poly(methyl methacrylate). Recently, this problem has been solved by several lines of material research using fluorinated polymers. As a result, high‐speed optical home networking by POFs has become more realistic. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011
Risk factors for current wheezing and its phenotypes among elementary school children
Authors: Civelek Ersoy , Cakir Banu , Orhan Fazıl , Yuksel Hasan , Boz Aysen B. , Uner Abdurrahman , Sekerel Bulent E.
Published: November 2010

Background

Accumulating evidence suggests, asthma includes many phenotypes with varying clinical and prognostic features. Epidemiological surveys documented a number of environmental risk factors for the development of asthma and interestingly these differ between and within countries, suggesting that the differences may be related with the different distribution of asthma phenotypes. This study aimed to investigate risk factors of current wheezing (CW) and different wheezing phenotypes in elementary school children.

Methods

Six thousand nine hundred sixty‐three 9‐ to 11‐year‐old children of a previous multicenter survey where the methodology of the International Study of Asthma and Allergies in Childhood (ISAAC) Phase‐II was used were analyzed. Wheezing phenotypes were defined as wheezing with rhinitis (RW), wheezing with rhinoconjunctivitis (RCW), atopic wheezing (AW), non‐atopic wheezing (NAW), and frequent wheezing (FW) (≥4/year wheezing episodes).

Results

The prevalence of CW was 15.8% and among these, 22.4%, 67.3%, 45.9%, 20.5%, and 79.5% were classified as FW, RW, RCW, AW, and NAW, respectively. History of parental asthma/allergic rhinitis, coexistence of other allergic diseases, presence of mold and dampness in the house lived during the first year of life and maternal smoking in pregnancy were found to be risk factors for most phenotypes (odds ratio (OR) ranged from 1.43 to 3.56). Number of household in the last year (OR = 1.14), prematurity (OR = 2.08), and duration of breastfeeding (OR = 1.02) per additional month were found to be risk factor for FW, AW, and RCW, respectively.

Conclusion

Beside common risk factors for the development of asthma and its phenotypes, certain risk factors appeared to play a role in the development of phenotypic characteristics of asthma. These findings support our hypothesis that each phenotype has not only different clinical characteristics but also has different roots. Pediatr. Pulmonol. 2011; 46:166–174. © 2011 Wiley‐Liss, Inc.
Respiratory syncytial virus prevention and therapy: Past, present, and future
Authors: Wright Melvin , Piedimonte Giovanni
Published: November 2010

Respiratory syncytial virus (RSV) is the most common respiratory pathogen in infants and young children worldwide. More than 50 years after its discovery, and despite relentless attempts to identify pharmacological therapies to improve the clinical course and outcomes of this disease, the most effective therapy remains supportive care. Although the quest for a safe and effective vaccine remains unsuccessful, pediatricians practicing during the past decade have been able to protect at least the more vulnerable patients with safe and effective passive prophylaxis. This review summarizes the history, microbiology, epidemiology, pathophysiology, and clinical manifestations of this infection in order to provide the reader with the background information necessary to fully appreciate the many challenges presented by the clinical management of young children with bronchiolitis. The last part of this article attempts an evidence‐based review of the pharmacologic strategies currently available and those being evaluated, intentionally omitting highly experimental approaches not yet tested in clinical trials and, therefore, not likely to become available in the foreseeable future. Pediatr Pulmonol. 2011; 46:324–347. © 2010 Wiley‐Liss, Inc.
The action of fish peptide Orpotrin analogs on microcirculation
Authors: Conceição Katia , Bruni Fernanda Miriane , Santos Juliane M. , Lopes Robson Melo , Marques Elineide E. , Fernandez Jorge H. , Lopes‐Ferreira Mônica
Published: November 2010

In order to investigate the relationship between the primary structure of Orpotrin, a vasoactive peptide previously isolated from the freshwater stingray Potamotrygon gr. orbignyi, and its microcirculatory effects, three Orpotrin analogs were synthesized. The analogs have a truncated N‐terminal with a His residue deletion and two substituted amino acid residues, where one Nle is substituted for one internal Lys residue and the third analog has a substitution of a Pro for an Ala (Orp‐desH1, Orp‐Nle and Orp‐Pro/Ala, respectively). Only Orp‐desH1 could induce a lower vasoconstriction effect compared with the natural Orpotrin, indicating that besides the N‐terminal, the positive charge of Lys and the Pro residues located at the center of the amino acid chain is crucial for this vasoconstriction effect. Importantly, the suggestions made with bioactive peptides were based on the molecular modeling and dynamics of peptides, the presence of key amino acids and shared activity in microcirculation, characterized by intravital microscopy. Moreover, this study has demonstrated that even subtle changes in the primary structure of Orpotrin alter the biological effects of this native peptide significantly, which could be of interest for biotechnological applications. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Effect of UV radiation on the reactivity of porous methyl‐doped SiO2 layers
Authors: Dultsev Fedor N.
Published: November 2010

The effect of plasma treatment on the chemical reactivity of the surface of porous layers based on methyl‐doped silicon dioxide is considered. A principal difference between the effects of plasma on materials with the pores of different sizes is demonstrated. It is shown that the VUV irradiation passivates the surface of the layers with smaller pores (1.1 nm in radius), while the films with larger pores (5.5 nm) do not get passivated (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantitative analysis of curro pore growth on n‐type InP
Authors: Leisner Malte , Carstensen Jürgen , Föll Helmut
Published: November 2010

In this work the growth of currentline‐oriented pores (curro pores) in (100) n‐type InP has been investigated on substrates of different doping concentration ND. Additionally, Fast‐Fourier‐Transform Impedance Spectroscopy (FFT IS) has been performed in‐situ during the etching. In the framework of the developed model of curro pore growth it was possible to extract quantitative data, which were hitherto not retrievable in‐situ. These data include the potential drop in the space‐charge‐region at the pore tips USCR and the corresponding space‐charge‐region capacitance CSCR, which are now directly accessible by FFT IS. Moreover, the width of the space‐charge‐region dSCR could be calculated, which defines the pore wall thickness, i.e. the doping concentration dependent spacing of the curro pores in the hexagonal lattice in which the curro pores grow for all doping concentrations.

The critical field strength of the avalanche breakdown – the mechanism of hole‐generation during curro pore growth – could also be calculated from the experimental data. It could be shown that the growth mode of curro pores is based on a constant potential drop at the pore tips, which together with a constant pore tip geometry keeps the maximum field strength Em of the avalanche breakdown process at the pore tips constant. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparison of currentline pore growth in n‐type InP and in n‐type Si
Authors: Cojocaru Ala , Leisner Malte , Carstensen Jürgen , Föll Helmut
Published: November 2010

In this work the growth of currentline‐oriented pores in (100) n‐type InP and in (100) n‐type Si for different doping concentrations has been studied. The pore morphology of both pore types is very similar, as is the characteristic behavior of the etching current. These similarities strongly indicate, that the underlying growth mechanisms of these pores in InP and Si are the same. A model for the currentline pores in both semiconductors is introduced, focusing on the strong diffusion limitation of species (reactants or products) at the pore tips. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photonic porous silicon‐based hybrid particles by soft‐lithography
Authors: Cheng Hua , Zhou Xuechang , Tsang Chun Kwan , Cheng Jian‐Wen , Liang Fengxia , Zheng Bo , Li Yang Yang
Published: November 2010

Here we present a simple and effective method to fabricate porous silicon photonic crystal‐based hybrid particles by soft lithography. These fabricated hybrid particles are composed of pristine porous silicon structures strengthened by a polymer infused nanocomposite framework. The pristine porous silicon moiety serves as a sensor because of its environmentally sensitive optical features, while the polymer‐infused moiety provides a mechanically resilient scaffold and its invariant optical features can be used as an optical barcode and a built‐in self‐reference for optical sensing. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Impregnation of porous silicon with conducting polymers
Authors: Harraz Farid A.
Published: November 2010

Fabrication of porous silicon layers using the electrochemical technique followed by filling the nanopores with a group of conducting polymers is investigated. Our findings revealed that the deposition of polymer proceeds homogeneously inside the nanopores strating from the pore bottom and propagates into the outer surface. The polymerization process was conducted and controlled by the potentiostatic and galvanostatic modes with charactarestic, defined polymerization stages.

As‐formed hybrid nanocomposites were charactarized using different analytical techniques. Polypyrrole, polyaniline and polythiophene were tested in this study. By selective dissolution of porous silicon template, polymeric nanowires were obtained. The fabrication process, the electrochemical measurements and the porous silicon filling mechanism with polymer are throughly addressed and discussed (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Carrier mobilities in multicrystalline silicon wafers made from UMG‐Si
Authors: Lim Bianca , Wolf Martin , Schmidt Jan
Published: November 2010

We investigate majority‐ and minority‐carrier mobilities in multicrystalline silicon (mc‐Si) made from upgraded metallurgical‐grade (UMG) feedstock. Since UMG‐Si contains high amounts of both boron and phosphorus, a decrease of the carrier mobility due to increased scattering at ionized impurities is expected. Minority‐carrier mobilities are determined by measuring effective carrier lifetimes τeff on as‐cut wafers, where τeff is limited by carrier diffusion to the unpassivated surfaces. By examining a wafer cut vertically from the mc‐Si ingot, we indeed find a reduction in minority‐carrier mobility μmin with increasing dopant density. In addition, we find a further strong reduction of μmin in the transition region from p ‐ to n ‐type silicon. Similar results are obtained regarding the majority‐carrier mobility μmaj, which is investigated by combining measurements of the resistivity ρ and the equilibrium hole concentration p0 (equilibrium electron concentration n0 in n ‐type material) obtained from electrochemical capacitance‐voltage measurements. Apart from an overall reduction in μmaj compared to values measured in non‐compensated p ‐type mc‐Si, an additional pronounced decrease of the mobility with increasing compensation level is observed. This additional reduction can be explained by reduced screening of the ionized scattering centers. We propose a parameterization of the experimental data based on the Brooks‐Herring equation and find excellent agreement between the two (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Reduction of absorption loss in multicrystalline silicon via combination of mechanical grooving and porous silicon
Authors: Ben Rabha Mohamed , Mohamed Seifeddine Belhadj , Dimassi Wissem , Gaidi Mounir , Ezzaouia Hatem , Bessais Brahim
Published: November 2010

Surface texturing of silicon wafer is a key step to enhance light absorption and to improve the solar cell performances. While alkaline‐texturing of single crystalline silicon wafers was well established, no efficient chemical solution has been successfully developed for multicrystalline silicon wafers. Thus, the use of alternative new methods for effective texturization of multicrystalline silicon is worth to be investigated. One of the promising texturing techniques of multicrystalline silicon wafers is the use of mechanical grooves. However, most often, physical damages occur during mechanical grooves of the wafer surface, which in turn require an additional step of wet processing‐removal damage. Electrochemical surface treatment seems to be an adequate solution for removing mechanical damage throughout porous silicon formation. The topography of untreated and porous silicon‐treated mechanically textured surface was investigated using scanning electron microscopy (SEM). As a result of the electrochemical surface treatment, the total reflectivity drops to about 5% in the 400‐1000 nm wavelength range and the effective minority carrier diffusion length enhances from 190 µm to about 230 µm (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A natural source of porous biosilica for nanotech applications: the diatoms microalgae
Authors: De Stefano Luca , De Stefano Mario , De Tommasi Edoardo , Rea Ilaria , Rendina Ivo
Published: November 2010

Several biological organisms, from some sea shells to butterflies, exhibit beautiful and sophisticated organs, developed during the evolution of each species, which properties are defined by their nanostructures. The marine diatoms are microscopic algae enclosed between two valves of hydrated amorphous silica. These intricate structures, called frustules, show quite symmetric patterns of micrometric and nanometric pores. Their strong similarity with man‐made materials, such as synthetic zeolites, or porous silicon and alumina, suggests to exploit the physical properties of the frustules in nanotech applications. In this paper, we review the most relevant results achieved in our laboratory, and all over the world, about the discovery of surprising features that can be found in the characterization of these natural porous biosilica materials. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mesoporous silicon particles as intravascular drug delivery vectors: fabrication, in‐vitro, and in‐vivo assessments
Authors: Chiappini Ciro , Tasciotti Ennio , Serda Rita E. , Brousseau Lou , Liu Xuewu , Ferrari M.
Published: November 2010

Porous silicon is an attractive biomaterial for drug delivery thanks to its biocompatibility, biodegradability, ease of fabrication, tunable nanostructure, and porous network. Herein we briefly present the development of a multi‐stage delivery vector that leverages these advantages to enhance delivery of systemically administered therapeutic agents. We illustrate the rational design, objective‐oriented fabrication and geometric control of first stage porous silicon microparticles. We describe how geometry affects the biodistribution of first stage vectors and how their porous structure affects the loading and release of second stage theranostic payloads. We describe the mechanism of cellular internalization and intracellular trafficking of particles. Finally we present two multi‐stage vector prototypes for the delivery of magnetic resonance imaging contrast agents and small interfering RNA (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Impedance spectra under forward and reverse bias conditions in gold/porous silicon/p‐Si structures
Authors: Fonthal Faruk , Chavarria Mario A.
Published: November 2010

Abstract – The AC electrical characterization of Au/porous silicon/p‐Si structure is presented. The low porosity porous silicon layers were prepared by electrochemical etching in p‐type silicon 〈100〉 with two resistivities. The AC electrical measurements capacitance–conductance–frequency were performed from 5 Hz to 10 MHz, at room temperature in the DC range of ±2 V. We studied two structures; first a conductor type Au/PS/Au and second diode type Au/PS/p‐Si/Al. We found the relationship between the bias voltage in the PS/p‐Si heterostructures with the depletion region formation and the conduction mechanism presents in these structures. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Chrysophanic acid blocks proliferation of colon cancer cells by inhibiting EGFR/mTOR pathway
Authors: Lee Myung Sun , Cha Eun Young , Sul Ji Young , Song In Sang , Kim Ji Yeon
Published: November 2010

Inactivation of epidermal growth factor receptor (EGFR) is a prime method used in colon cancer therapy. Here it is shown that chrysophanic acid, a natural anthraquinone, has anticancer activity in EGFR‐overexpressing SNU‐C5 human colon cancer cells. Chrysophanic acid preferentially blocked proliferation in SNU‐C5 cells but not in other cell lines (HT7, HT29, KM12C, SW480, HCT116 and SNU‐C4) with low levels of EGFR expression. Chrysophanic acid treatment in SNU‐C5 cells inhibited EGF‐induced phosphorylation of EGFR and suppressed activation of downstream signaling molecules, such as AKT, extracellular signal‐regulated kinase (ERK) and the mammalian target of rapamycin (mTOR)/ribosomal protein S6 kinase (p70S6K). Chrysophanic acid (80 and 120 µm) significantly blocked cell proliferation when combined with the mTOR inhibitor, rapamycin. These findings offer the first evidence of anticancer activity for chrysophanic acid via EGFR/mTOR mediated signaling transduction pathway. Copyright © 2010 John Wiley & Sons, Ltd.
Routine TOF‐SIMS instrument control using polycarbonate material
Authors: Fartmann Michael , Kersting Reinhard , Hagenhoff Birgit
Published: November 2010

We suggest the use of polycarbonate as reference material for the routine time of flight (TOF) SIMS (TOF‐SIMS) instrument control under quality management regulations (e.g. ISO/IEC 17025:2005). By monitoring an easy‐to‐determine relative peak area ratio, the performance of TOF‐SIMS instruments can well be assessed, in particular, with respect to the characterization of insulating samples. Copyright © 2010 John Wiley & Sons, Ltd.
Aldehyde Dehydrogenase Activity of Breast Cancer Stem Cells Is Primarily Due To Isoform ALDH1A3 and Its Expression Is Predictive of Metastasis
Authors: Marcato Paola , Dean Cheryl A. , Pan Da , Araslanova Rakhna , Gillis Megan , Joshi Madalsa , Helyer Lucy , Pan Luzhe , Leidal Andrew , Gujar Shashi , Giacomantonio Carman A. , Lee Patrick W. K.
Published: November 2010

Cancer stem cells (CSCs) are proposed to initiate cancer and propagate metastasis. Breast CSCs identified by aldehyde dehydrogenase (ALDH) activity are highly tumorigenic in xenograft models. However, in patient breast tumor immunohistological studies, where CSCs are identified by expression of ALDH isoform ALDH1A1, CSC prevalence is not correlative with metastasis, raising some doubt as to the role of CSCs in cancer. We characterized the expression of all 19 ALDH isoforms in patient breast tumor CSCs and breast cancer cell lines by total genome microarray expression analysis, immunofluorescence protein expression studies, and quantitative polymerase chain reaction. These studies revealed that ALDH activity of patient breast tumor CSCs and cell lines correlates best with expression of another isoform, ALDH1A3, not ALDH1A1. We performed shRNA knockdown experiments of the various ALDH isoforms and found that only ALDH1A3 knockdown uniformly reduced ALDH activity of breast cancer cells. Immunohistological studies with fixed patient breast tumor samples revealed that ALDH1A3 expression in patient breast tumors correlates significantly with tumor grade, metastasis, and cancer stage. Our results, therefore, identify ALDH1A3 as a novel CSC marker with potential clinical prognostic applicability, and demonstrate a clear correlation between CSC prevalence and the development of metastatic breast cancer.
PKCδ-Induced PU.1 Phosphorylation Promotes Hematopoietic Stem Cell Differentiation to Dendritic Cells
Authors: Hamdorf Matthias , Berger André , Schüle Silke , Reinhardt Jens , Flory Egbert
Published: November 2010

Human CD34+ hematopoietic stem cells (HSCs) exhibit the potential to differentiate into a variety of specialized blood cells. The distinct intracellular mechanisms that control cell fate and lineage commitment of these multipotent cells are not well defined. In this study, we investigate and modulate the signaling processes during HSC differentiation toward myeloid dendritic cells (mDCs). DC differentiation induced by the cytokines Granulocyte macrophage colony-stimulating factor (GM-CSF) and Interleukin-4 (IL-4) led to activation of the Extracellular-signal-regulated kinase (ERK), protein kinase C (PKC), and Janus kinase (JAK)/Signal Transducer and Activator of Transcription (STAT) but not the SAPK/c-Jun NH2-terminal kinase and p38 mitogen-activated protein kinase signaling pathways. From the activated signaling pathways the PKC isoform δ was found to phosphorylate the transcription factor PU.1, which is described as one of the key factors for myeloid HSC differentiation. On molecular level, PKCδ regulated PU.1 activity by affecting its transactivation activity, whereas its DNA binding activity remained unaffected. This was accompanied by PKCδ-induced phosphorylation of the PU.1 transactivation domain. Furthermore, treatment with PKC- and ERK1/2-specific signaling inhibitors impaired both HSC differentiation toward mDCs as well as phosphorylation-mediated transactivation activity of PU.1. Taken together, these results provide new insights into the molecular mechanisms promoting the differentiation process of HSCs toward mDCs and introduce the PKC isoform δ as critical mediator.
The Apical Polarity Determinant Crumbs 2 Is a Novel Regulator of ESC-Derived Neural Progenitors
Authors: Boroviak Thorsten , Rashbass Penny
Published: November 2010

ESCs undergoing neural differentiation in vitro display an intrinsic heterogeneity with a large subset of the cells forming polarized neural rosettes that maintain the neural progenitor microenvironment. This heterogeneity is not only necessary for normal development but also causes substantial technical challenges for practical applications. Here, we report a novel regulator of early neural progenitors, the apical polarity protein Crb2 (Crumbs homologue 2). Employing monolayer differentiation of mouse ESCs to model neurogenesis in vitro, we find that Crb2 is upregulated with Sox1 and Musashi at the onset of neuroepithelial specification and localizes to the apical side of neural rosettes. Stable Crb2-knockdown (KD) lines die at the onset of neural specification and fail to stabilize several apical polarity proteins. However, these cells are able to proliferate under self-renewing conditions and can be differentiated into mesodermal and endodermal lineages. Conversely, Crb2 overexpression during neural differentiation results in elevated levels of other apical polarity proteins and increases proliferation. Additionally, sustained overexpression of Crb2 reduces terminal differentiation into TuJ1-positive neurons. Furthermore, we demonstrate that Crb2 overexpression under self-renewing conditions increases glycogen synthase kinase (GSK)-3β inhibition, correlating with an increase in clonogenicity. To confirm the importance of GSK-3β inhibition downstream of Crb2, we show that Crb2-KD cells can be forced into neural lineages by blocking GSK-3β function and supplementing Epidermal Growth Factor (EGF) and basic Fibroblast Growth Factor (bFGF). Thus, this is the first demonstration that a member of the Crumbs family is essential for survival and differentiation of ESC-derived neural progenitors.
Dynamic optimal route search algorithm for car navigation systems with preferences by dynamic programming
Authors: Mainali Manoj Kanta , Mabu Shingo , Yu Shanqing , Eto Shinji , Hirasawa Kotaro
Published: November 2010

Optimal route search to the destination is one of the most important functions of car navigation devices. The development of road traffic infrastructure has made it possible to receive real‐time information of the traffic situation. Route search algorithms for car navigation devices make use of this information to avoid the traffic congestions. Such algorithms should find the new optimal route efficiently when the traffic situation changes. Usually, the minimum traveling time or distance is considered to define the optimal route. However, the minimum traveling time or distance is not always what the user is looking for. The user may prefer to travel on a certain route even at the cost of traveling time or distance. Car navigation devices should consider such preferences when finding the optimal route. In this paper, we propose a dynamic programming algorithm to find the optimal route considering that it should deal with the changes of the traffic situation and multiple criteria. The proposed method uses the information from the previous computation to find the new optimal route considering user preferences when the traveling time of the road section changes. The proposed method was applied to a real road network to find the optimal route. Results show that the proposed method can find the user‐preferred optimal route. Simulation results also show better calculation time of the proposed method compared to the Dijkstra algorithm. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
A minute asymmetrical current injection based anti‐islanding method for three‐phase grid‐connected photovoltaic inverters
Authors: Sun Xiang‐Dong , Matsui Mikihiko , Yu Byung‐Gyu , Koh Kang‐Hoon
Published: November 2010

An active anti‐islanding protection method based on the current control for a three‐phase grid‐connected photovoltaic inverter is proposed in this paper. The current of phase‐a is synchronous with the corresponding phase voltage at the point of common coupling in its positive half cycle, and a zero‐current zone is inserted at the end of the cycle in a negative half cycle. As for phase‐c, the zero‐current zone is inserted in the positive half cycle of the current, and the current in a negative half cycle of phase‐c is in phase with the corresponding phase voltage. Therefore, the currents of phase‐a and phase‐c in one cycle become slightly asymmetrical. Before the islanding takes place, the positive and negative half cycles of three‐phase voltages are symmetrical due to the operation of the grid voltage. While islanding takes place, a time difference between the positive and negative half cycles of the voltages of phase‐a and phase‐c will be generated and the islanding is detected in accordance with the successive cycles fulfilling the conditions of islanding identification. In order to measure zero‐crossings of the voltages accurately, an finite impulse response filter is used to smooth out the voltage harmonics and noises. Simulations and experiments for three‐phase three‐wire power systems have been carried out. The results verify that the proposed method can detect the islanding for a parallelRLCload or induction motors when the voltage frequency is within the range of the non‐detection zone. It is seen from the analysis of the detecting principle that there is no influence of temporal voltage frequency fluctuation on the proposed method even if a large load connected to a weak power system frequently starts up or stops. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Numerical study of the oscillation characteristics of a surface wave oscillator
Authors: Watanabe Osamu
Published: November 2010

The oscillation characteristics of a surface wave oscillator is analyzed numerically. The oscillation frequency due to Cherenkov instability can be controlled by the electron beam energy though the alteration of the accompanying temporal growth rate. The growth rate increases exponentially with the proximity of the beam to a corrugated metal plate. The oscillation frequency is not changed by this proximity. The peak of the growth rate of the Cherenkov instability is one or more orders higher than that of a Smith–Purcell type instability. Moreover, in frequency and wavenumbers, the difference of two instabilities is enlarged by the increase in the growth rate. Therefore, the influence of the Smith–Purcell type instability on the Cherenkov instability is decreased. IEEJ Trans 2010 DOI: 10.1002/tee.20611
Reduced order model predictive control with disturbance attenuation
Authors: Takahashi Masaaki , Hara Naoyuki , Kokame Hideki , Konishi Keiji
Published: November 2010

This paper deals with model predictive control (MPC) with disturbance attenuation. By introducing a decomposition method for a quadratic objective function, an MPC law is obtained from a reduced order optimization problem. The effectiveness of the proposed MPC law is demonstrated by numerical simulation.IEEJ Trans2010 DOI: 10.1002/tee.20613
New aids for the non‐invasive prenatal diagnosis of achondroplasia: dysmorphic features, charts of fetal size and molecular confirmation using cell‐free fetal DNA in maternal plasma
Authors: Chitty L. S. , Griffin D. R. , Meaney C. , Barrett A. , Khalil A. , Pajkrt E. , Cole T. J.
Published: November 2010

Objectives

To improve the prenatal diagnosis of achondroplasia by constructing charts of fetal size, defining frequency of sonographic features and exploring the role of non‐invasive molecular diagnosis based on cell‐free fetal deoxyribonucleic acid (DNA) in maternal plasma.

Methods

Data on fetuses with a confirmed diagnosis of achondroplasia were obtained from our databases, records reviewed, sonographic features and measurements determined and charts of fetal size constructed using the LMS (lambda‐mu‐sigma) method and compared with charts used in normal pregnancies. Cases referred to our regional genetics laboratory for molecular diagnosis using cell‐free fetal DNA were identified and results reviewed.

Results

Twenty‐six cases were scanned in our unit. Fetal size charts showed that femur length was usually on or below the 3rd centile by 25 weeks' gestation, and always below the 3rd by 30 weeks. Head circumference was above the 50th centile, increasing to above the 95th when compared with normal for the majority of fetuses. The abdominal circumference was also increased but to a lesser extent. Commonly reported sonographic features were bowing of the femora, frontal bossing, short fingers, a small chest and polyhydramnios. Analysis of cell‐free fetal DNA in six pregnancies confirmed the presence of the c.1138G > A mutation in the FGRF3 gene in four cases with achondroplasia, but not the two subsequently found to be growth restricted.

Conclusions

These data should improve the accuracy of diagnosis of achondroplasia based on sonographic findings, and have implications for targeted molecular confirmation that can reliably and safely be carried out using cell‐free fetal DNA. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Can orthopaedic clinicians learn to read skeletal bone age? An inter- and intra observer study between specialties
Authors: Rajan R. A. , Swindells M. G. , Metcalfe J. E. , Konstantoulakis C.
Published: November 2010

Objective

Determination of skeletal age is essential for predicting eventual leg length discrepancies and predicting the accurate timing for surgical intervention in order to correct any discrepancy. To our knowledge, there has not been an interdisciplinary comparison of the degree of agreement in determining skeletal bone age.

Materials and methods

We evaluated 30 left hand/wrist radiographs (children aged 16 months to 10 years 6 months) on two separate occasions between musculoskeletal paediatric radiologists, paediatric orthopaedic surgeons and a senior radiographer after appropriate training.

Results

All clinicians were able to reliably age patients with good intra- and interobserver agreement.

Conclusion

We suggest that following tuition, orthopaedic surgeons are able to reliably age patients from X-rays.
A cross-sectional study of dietary patterns with glucose intolerance and other features of the metabolic syndrome
Authors: Williams Desmond E. M. , Prevost A. Toby , Whichelow Margaret J. , Cox Brian D. , Day Nicholas E. , Wareham Nicholas J.
Published: November 2010

Previous epidemiological studies have demonstrated relationships between individual nutrients and glucose intolerance and type 2 diabetes, but the association with the overall pattern of dietary intake has not previously been described. In order to characterize this association, 802 subjects aged 40–65 years were randomly selected from a population-based sampling frame and underwent a 75 g oral glucose-tolerance test. Principal component analysis was used to identify four dietary patterns explaining 31·7 % of the dietary variation in the study cohort. These dietary patterns were associated with other lifestyle factors including socio-economic group, smoking, alcohol intake and physical activity. Component 1 was characterized by a healthy balanced diet with a frequent intake of raw and salad vegetables, fruits in both summer and winter, fish, pasta and rice and low intake of fried foods, sausages, fried fish, and potatoes. This component was negatively correlated with central obesity, fasting plasma glucose, 120 min non-esterified fatty acid and triacylglycerol, and positively correlated with HDL-cholesterol. It therefore appears to be protective for the metabolic syndrome. Component 1 was negatively associated with the risk of having undiagnosed diabetes, and this association was independent of age, sex, smoking and obesity. The findings support the hypothesis that dietary patterns are associated with other lifestyle factors and with glucose intolerance and other features of the metabolic syndrome. The results provide further evidence for the recommendation of a healthy balanced diet as one of the main components of chronic disease prevention.
Regulatory mechanisms of intestinal folate uptake in a rat model of folate oversupplementation
Authors: Dev Som , Ahmad Wani Nissar , Kaur Jyotdeep
Published: November 2010

Folic acid is essential for numerous biological functions, ranging from nucleotide biosynthesis to the remethylation of homocysteine. Folic acid is unable to cross the biological membranes by simple diffusion, so there exists a well-developed epithelial folate transport system for the regulation of normal folate homeostasis in the intestine. Any perturbances in the folate uptake system might lead to a state of folate deficiency, which in turn is strongly associated with the risk of various cancers, birth defects and CVD. Countries with obligatory folate fortification of food (USA and Canada) have documented a significant decrease in neural tube defects in newborns. However, the effect of folate oversupplementation on the intestinal absorption of folic acid has not been studied. We studied the process of folate transport and the expression of folate transporters in the rat intestine after folate oversupplementation. Rats were oversupplemented with tenfold the normal requirement of folic acid for periods of 10 and 60 d. Folate uptake in intestinal brush-border membrane vesicles followed saturable kinetics with pH optimum at 5·5. Acute, but not chronic, folate oversupplementation led to a significant down-regulation in intestinal folate uptake at acidic pH optima and was associated with a decrease inVmaxwithout any significant change in theKmof the folate uptake process. The decrease in folate uptake was also associated with the down-regulation in the protein levels of major folate transporters, proton-coupled folate transporter (PCFT) and reduced folate carrier (RFC), without altering their mRNA levels. Hence, it was concluded that acute folate oversupplementation results in a significant decrease in intestinal folate uptake by down-regulating the expressions of RFC and PCFT, via some post-transcriptional or translational mechanisms.
Micronutrients and the pathogenesis of human immunodeficiency virus infection
Authors: Semba R. D. , Tang A. M.
Published: November 2010

Micronutrient deficiencies may be common during human immunodeficiency virus (HIV) infection. Insufficient dietary intake, malabsorption, diarrhoea, and impaired storage and altered metabolism of micronutrients can contribute to the development of micronutrient deficiencies. Low plasma or serum levels of vitamins A, E, B6, B12and C, carotenoids, Se, and Zn are common in many HIV-infected populations. Micronutrient deficiencies may contribute to the pathogenesis of HIV infection through increased oxidative stress and compromised immunity. Low levels or intakes of micronutrients such as vitamins A, E, B6and B12, Zn and Se have been associated with adverse clinical outcomes during HIV infection, and new studies are emerging which suggest that micronutrient supplementation may help reduce morbidity and mortality during HIV infection.
Henry Dunant
Authors: Boissier Pierre
Published: November 2010

A short biography of Henry Dunant that will appeal to readers of all kinds has so far been lacking. By an extraordinary stroke of luck, Pierre Boissier, Director of the Institute that bears the name of the originator of the Red Cross, had dictated an essay on those lines shortly before his death. The very day before the tragic accident in which he lost his life, he had gone through his draft and had asked Mme Yvonne de Pourtalès to complete and put the finishing touches to it. This she has accomplished remarkably well in all respects.