bluuebunny/crossref_metadata_2025 huggingface dataset:
Down‐regulation of Notch‐1 and Jagged‐1 inhibits prostate cancer cell growth, migration and invasion, and induces apoptosis via inactivation of Akt, mTOR, and NF‐κB signaling pathways
Authors: Wang Zhiwei , Li Yiwei , Banerjee Sanjeev , Kong Dejuan , Ahmad Aamir , Nogueira Veronique , Hay Nissim , Sarkar Fazlul H
Published: January 2010

Notch signaling is involved in a variety of cellular processes, such as cell fate specification, differentiation, proliferation, and survival. Notch‐1 over‐expression has been reported in prostate cancer metastases. Likewise, Notch ligand Jagged‐1 was found to be over‐expressed in metastatic prostate cancer compared to localized prostate cancer or benign prostatic tissues, suggesting the biological significance of Notch signaling in prostate cancer progression. However, the mechanistic role of Notch signaling and the consequence of its down‐regulation in prostate cancer have not been fully elucidated. Using multiple cellular and molecular approaches such as MTT assay, apoptosis assay, gene transfection, real‐time RT‐PCR, Western blotting, migration, invasion assay and ELISA, we found that down‐regulation of Notch‐1 or Jagged‐1 was mechanistically associated with inhibition of cell growth, migration, invasion and induction of apoptosis in prostate cancer cells, which was mediated via inactivation of Akt, mTOR, and NF‐κB signaling. Consistent with these results, we found that the down‐regulation of Notch‐1 or Jagged‐1 led to decreased expression and the activity of NF‐κB downstream genes such as MMP‐9, VEGF, and uPA, contributing to the inhibition of cell migration and invasion. Taken together, we conclude that the down‐regulation of Notch‐1 or Jagged‐1 mediated inhibition of cell growth, migration and invasion, and the induction of apoptosis was in part due to inactivation of Akt, mTOR, and NF‐κB signaling pathways. Our results further suggest that inactivation of Notch signaling pathways by innovative strategies could be a potential targeted approach for the treatment of metastatic prostate cancer. J. Cell. Biochem. 109: 726–736, 2010. © 2010 Wiley‐Liss, Inc.
Differentiation of human umbilical cord Wharton's jelly‐derived mesenchymal stem cells into germ‐like cells in vitro
Authors: Huang Peng , Lin Li Min , Wu Xiao Ying , Tang Qiu Ling , Feng Xue Yong , Lin Guang Yu , Lin Xiaobo , Wang Hong Wu , Huang Tian Hua , Ma Lian
Published: January 2010

Recent studies have demonstrated that mesenchymal stem cells could differentiate into germ cells under appropriate conditions. We sought to determine whether human umbilical cord Wharton's jelly‐derived mesenchymal stem cells (HUMSCs) could form germ cells in vitro. HUMSCs were induced to differentiate into germ cells in all‐trans retinoic acid, testosterone and testicular‐cell‐conditioned medium prepared from newborn male mouse testes. HUMSCs formed “tadpole‐like” cells after induction with different reagents and showed both mRNA and protein expression of germ‐cell‐specific markers Oct4 (POUF5), Ckit, CD49f (α6), Stella (DDPA3), and Vasa (DDX4). Our results may provide a new route for reproductive therapy involving HUMSCs and a novel in vitro model to investigate the molecular mechanisms that regulate the development of the mammalian germ lineage. J. Cell. Biochem. 109: 747–754, 2010. © 2010 Wiley‐Liss, Inc.
Acid catalyzed halogen dance on deactivated pyrroles
Authors: Tutino Federico , Papeo Gianluca , Quartieri Francesca
Published: January 2010

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A study on the acid catalyzed halogen dance (ACHD) on deactivated bromopyrroles is reported. A different behavior is observed when considering singly deactivated pyrrole alkylcarboxamides, or doubly deactivated pyrroleketo‐lactams (aldisines). Although less electron deficient pyrrole alkylcarboxamides suffer from ACHD, the double deactivation on keto‐lactams disfavors pyrrole ring protonation thus preventing halogen scrambling. The mechanism involved in the rearrangement is hypothesized. J. Heterocyclic Chem., 2010.
An efficient synthesis of pyrido[2,3‐d]pyrimidine derivatives in ionic liquid
Authors: Shi Da‐Qing , Zhou Yao , Liu Hai
Published: January 2010

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A series of 5,7‐diarylpyrido[2,3‐d]pyrimidine‐2,4(1H,3H)‐diones was synthesized via the reaction of 6‐aminopyrimidine‐2,4‐dione and α,β‐unsaturated ketones in ionic liquid without using any catalyst. This protocol has the advantages of easier work‐up, milder reaction conditions, high yields, and environmentally benign procedure over traditional methods. J. Heterocyclic Chem., 2010.
Preparation of NH‐pyrazoleacetic acid anilides from trilithiated acetoacetanilide, select aromatic esters, and hydrazine
Authors: Smith Ellyn A. , Potter Chandra , Kennedy Zachary C. , Puciaty Andrew J. , Acevedo‐Jake Amanda M. , Hersey Stephen D. , Metz Clyde R. , Pennington William T. , VanDerveer Donald G. , Beam Charles F.
Published: January 2010

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Acetoacetanilide was trilithiated with excess lithium diisopropylamide to form a reactive trianion‐type intermediate. This was followed by a regioselective Claisen‐type condensation of the trilithiated intermediate with a variety of aromatic esters to afford new C‐acylated intermediates, 3,5‐diketopentane‐carboxanilides, that were not isolated but immediately condensed‐cyclized with hydrazine to afford the NH‐pyrazoleacetanilides, 5‐aryl‐1H‐pyrazole‐3‐acetanilides, before these C‐acylated intermediates had an opportunity to rearrange to anilino‐pyranones, 4‐anilino‐6‐aryl‐2H‐pyran‐2‐ones. J. Heterocyclic Chem., 2010.
Synthesis and structure of new 5‐(arylidene)‐3‐(4‐methylbenzoyl)thiazolidine‐2,4‐diones
Authors: Popov‐Pergal Katarina M. , Poleti Dejan , Rančić Milica P. , Meden Antun , Pergal Marija V.
Published: January 2010

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The derivatives of 5‐substituted‐2,4‐thiazolidinedione have a broad spectrum of biological activities. In this article, new 5‐(arylidene)‐3‐(4‐methylbenzoyl)thiayolidine‐2,4‐diones3a,3b,3c,3d,3e,3f,3g,3h,3i,3j,3kwith arylidene groups such as 4‐phenylbenzylidene3a, 3,4‐dimethoxybenzylidene3b, 2‐hydroxybenzylidene3c, 4‐ethoxybenzylidene3d, 5‐methyl‐2‐furfurylidene3e, 4‐dimethylaminobenzylidene3f, 1‐naphthylidene3g, 3,4‐methylenedioxybenzylidene3h, 4‐benzyloxybenzylidene3i, benzylidene3j, and 4‐methoxybenzylidene3k, were synthesized by direct acylation of alkali metal salts of 5‐arylidene‐2,4‐thiazolidinediones with 4‐methylbenzoylchloride. Their structures were confirmed by elemental analysis, IR,1H NMR and MS spectroscopy. In addition, crystal structure of the compound3dwas determined using single‐crystal X‐ray diffraction data. J. Heterocyclic Chem., 2010.
Raman spectroscopic study of the antimonate mineral bottinoite Ni[Sb2(OH)12]·6H2O and in comparison with brandholzite Mg[Sb5+2(OH)12]·6H2O
Authors: Frost Ray L. , Bahfenne Silmarilly
Published: January 2010

Raman spectroscopy was used to study the mineral bottinoite and a comparison with the Raman spectra of brandholzite was made. An intense sharp Raman band at 618 cm−1 is attributed to the SbO symmetric stretching mode. The low intensity band at 735 cm−1 is ascribed to the SbO antisymmetric stretching vibration. Low intensity Raman bands were found at 501, 516 and 578 cm−1. Four Raman bands observed at 1045, 1080, 1111 and 1163 cm−1 are assigned to δ SbOH deformation modes. A complex pattern resulting from the overlapping band of the water and hydroxyl units is observed. Raman bands are observed at 3223, 3228, 3368, 3291, 3458 and 3510 cm−1. The first two Raman bands are assigned to water stretching vibrations. The two higher wavenumber Raman bands observed at 3466 and 3552 cm−1 and two infrared bands at 3434 and 3565 cm−1 are assigned to the stretching vibrations of the hydroxyl units. Observed Raman and infrared bands are connected with OH···O hydrogen bonds and their lengths 2.72, 2.79, 2.86, 2.88 and 3.0 Å (Raman) and 2.73, 2.83 and 3.07 Å (infrared). Copyright © 2010 John Wiley & Sons, Ltd.
Preparation of Defined Albumin–Polymer Hybrids for Efficient Cell Transfection
Authors: Zöphel Lukas , Eisele Klaus , Gropeanu Radu , Rouhanipour Ali , Koynov Kaloian , Lieberwirth Ingo , Müllen Klaus , Weil Tanja
Published: January 2010

The preparation of two structurally defined protein–polymer hybrid architectures was presented by connecting two BSA proteins via a bifunctional poly(ethylene oxide) linker. The dimer consisting of native BSA with a negative net charge was characterized in solution as well as on surfaces, and no aggregation was observed. On a surface, defined architectures were found since both BSA subunits were efficiently separated by the PEO chain. After reaction of accessible, negatively charged amino acid residues with ethylenediamine, cBSA‐PEO dimers were achieved with a positive net charge in each subunit. These positively charged polyelectrolytes underwent complex formation with plasmid DNA coding for the luminescent enzyme luciferase. Efficient in vitro gene transfection was obtained with these protein polyelectrolytes and compared with polymer‐based gene transfection agents.

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Molecular‐Weight‐Controlled Brittle‐to‐Semiductile‐to‐Ductile Transition in S‐(S/B)‐S Triblock Copolymers
Authors: Ganß Martin , Satapathy Bhabani K. , Thunga Mahendra , Weidisch Roland , Knoll Konrad
Published: January 2010

Toughness enhancement of S‐(S/B)‐S triblock copolymers via a molecular‐weight‐controlled pathway is demonstrated. The post‐yield crack toughness behavior of the triblock copolymers uniquely reveal a brittle‐to‐semiductile‐to‐ductile transition with increasing$\overline M _{\rm w}$while keeping the basic molecular architecture fixed. TEM and SAXS investigations indicated three distinct morphologies as a function ofχeffNas a consequence of the increase in$\overline M _{\rm w}$: (i) a homogeneous structure without phase‐separation, (ii) a weakly segregated structure, and (iii) a lamellar structure. The increase in crack toughness is also reaffirmed from kinetic and strain field analysis studies concerning dynamics of crack growth in block copolymers with high PS content.

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Multifunctional Nanoscale Platforms for Targeting of the Cancer Cell Immortality Spectrum
Authors: Soundararajan Venkataramanan , Warnock Kenneth , Sasisekharan Ram
Published: January 2010

In the post‐genomic era, “omics” platforms and cancer systems biology are greatly advancing our knowledge of the molecular and cellular underpinnings of cancer. In this article, we begin by outlining the factors governing the development of cancer (tumorigenesis) and use this framework to motivate the need for systems‐approaches to cancer diagnostics and therapeutics. We review recent efforts to tap into the remarkable potential of nanotechnology for (i) systems‐surveillance (or “sensing”) of the molecular signatures of tumorigenesis, and (ii) spatiotemporally‐regulated delivery (or “targeting”) of combination therapeutics to cancer cells. Specifically, we highlight the salient role of polymeric biomaterials and describe the physicochemical characteristics that render them attractive for the design of such nanoscale platforms. We conclude with discussions on the emerging role of macromolecular biophysics and computational nanotechnology in engineering spatiotemporally‐regulated anti‐cancer systems.

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Electron Beam‐Based Functionalization of Poly(ethersulfone) Membranes
Authors: Schulze Agnes , Marquardt Barbara , Kaczmarek Sven , Schubert Rolf , Prager Andrea , Buchmeiser Michael R.
Published: January 2010

Poly(ethersulfone) membranes were surface modified in a one‐step procedure. For this purpose, the membranes were soaked with aqueous solutions of different low‐molecular weight molecules bearing diverse hydrophilic functionalities and subject to electron beam treatment. No catalysts, photoinitiators, organic solvents or other toxic reagents were used, and no additional synthetic or purification steps were required.

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Advances in the Elegance of Chemistry in Designing Dendrimers
Authors: Hourani Rami , Kakkar Ashok
Published: January 2010

Highly functional and monodisperse macromolecules with tailored architecture constitute the key to designing efficient and smart nanomaterials. Dendrimers offer real potential to achieve this goal, and one of the earlier challenges faced by this novel class of polymers has been addressed by the evolution of synthetic methodologies. This review provides an evaluation of the role played by chemistry in taking these macromolecules of academic relevance to practical industrial and biological applications, in a relatively short period. One can now construct dendrimers in a ‘made‐to‐order’ fashion, for numerous applications in a variety of disciplines.

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Multifunctional Magnetoplasmonic Nanoparticle Assemblies for Cancer Therapy and Diagnostics (Theranostics)
Authors: Chen Wei , Xu Naifeng , Xu Liguang , Wang Libing , Li Zuokun , Ma Wei , Zhu Yingyue , Xu Chuanlai , Kotov Nicholas A.
Published: January 2010

In this work, we describe the preparation and biomedical functionalities of complex nanoparticle assemblies with magnetoplasmonic properties suitable for simultaneous cancer therapy and diagnostics (theranostics). Most commonly magnetoplasmonic nanostructures are made by careful adaptation of metal reduction protocols which is both tedious and restrictive. Here we apply the strategy of nanoscale assemblies to prepare such systems from individual building blocks. The prepared superstructures are based on magnetic Fe3O4 nanoparticles encapsulated in silica shell representing the magnetic module. The cores are surrounded in a corona‐like fashion by gold nanoparticles representing the plasmonic module. As additional functionality they were also coated by poly(ethyleneglycol) chains as a cloaking agent to extend the blood circulation time. The preparation is exceptionally simple and allows one to vary the contribution of each function. Both modules can carry drugs and, in this study, they were loaded with the potential anticancer drug curcumin. A comprehensive set of microscopy, spectroscopy and biochemical methods were applied to characterize both imaging and therapeutic function of the nanoparticle assemblies against leukemia HL‐60 cells. High contrast magnetic resonance images and high apoptosis rates demonstrate the success of assembly approach for the preparation of magnetoplasmonic nanoparticles. This technology allows one to easily “dial in” the functionalities in the clinical setting for personalized theranostic regiments.

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Trends in childhood cancer incidence and mortality in urban Shanghai, 1973–2005
Authors: Bao Ping‐ping , Zheng Ying , Gu Kai , Wang Chun‐fang , Wu Chun‐xiao , Jin Fan , Lu Wei
Published: January 2010

Background

To describe trends in cancer incidence and mortality among children less than 15 years of age in urban Shanghai between 1973 and 2005.

Procedure

Annual rates of cancer incidence were calculated per 1,000,000 children for 3‐year intervals between 1973 and 2005. Linear regression models were used to analyze the annual percent change (APC) in incidence and mortality across these distinct intervals.

Results

For all cancers combined, the incidence rate during the observed time period did not substantially change in urban Shanghai. Rates for the incidence of individual cancer did exhibit variations. Leukemia incidence remained relatively stable but the incidence of myeloid leukemia decreased sharply in both males (APC −8.6%) and females (APC −9.5%). The rate of NHL varied little among males with APC 2.1% and modestly increased among females with APC 9.3%. Anatomic sites that only occasionally demonstrate malignancy, bone and joints in males and endocrines in females, showed upward trends in incidence. A significant reduction in liver cancer incidence in males was observed. Examining mortality rates, all cancer mortality decreased by −6.0% annually in males and by −3.9% in females. This trend was mainly due to the reduction in mortality for leukemia, particularly the myeloid subtype, which decreased in males (APC −7.2%) and females (APC −7.3%).

Conclusions

Childhood cancer incidence rates showed no substantial changes but mortality demonstrated a dramatic reduction during the observed time period, suggesting an improvement in both childhood cancer diagnosis and treatment. Pediatr Blood Cancer 2010;54:1009–1013 © 2010 Wiley‐Liss, Inc.
Severe ehrlichia infection in pediatric oncology and stem cell transplant patients
Authors: Esbenshade Adam , Esbenshade Jennifer , Domm Jennifer , Williams John , Frangoul Haydar
Published: January 2010

Ehrlichiosis, a tickborne illness transmitted by tick vectors Amblyomma americanum and Ixodes scapularis, can be acquired in endemic areas. Clinical manifestations range from asymptomatic to fulminant in nature. We report three cases of ehrlichiosis in pediatric oncology patients, one of whom was a stem cell transplant recipient. Early symptoms included fever, malaise, and vague gastrointestinal symptoms. Laboratory abnormalities were initially attributed to chemotherapy toxicity. Illness was severe in all three patients and one patient died even after initiation of doxycycline. These cases emphasize the need for a high index of suspicion for tickborne illness in oncology patients, and the importance of a low threshold for starting empiric treatment before confirming the diagnosis. Pediatr Blood Cancer 2010;54:776–778. © 2010 Wiley‐Liss, Inc.
Conserved tertiary couplings stabilize elements in the PDZ fold, leading to characteristic patterns of domain conformational flexibility
Authors: Ho Bosco K. , Agard David A.
Published: January 2010

Single‐domain allostery has been postulated to occur through intramolecular pathways of signaling within a protein structure. We had previously investigated these pathways by introducing a local thermal perturbation and analyzed the anisotropic propagation of structural changes throughout the protein. Here, we develop an improved approach, the Rotamerically Induced Perturbation (RIP), that identifies strong couplings between residues by analyzing the pathways of heat‐flow resulting from thermal excitation of rotameric rotations at individual residues. To explore the nature of these couplings, we calculate the complete coupling maps of 5 different PDZ domains. Although the PDZ domain is a well conserved structural fold that serves as a scaffold in many protein–protein complexes, different PDZ domains display unique patterns of conformational flexibility in response to ligand binding: some show a significant shift in a set of α‐helices, while others do not. Analysis of the coupling maps suggests a simple relationship between the computed couplings and observed conformational flexibility. In domains where the α‐helices are rigid, we find couplings of the α‐helices to the body of the protein, whereas in domains having ligand‐responsive α‐helices, no couplings are found. This leads to a model where the α‐helices are intrinsically dynamic but can be damped if sidechains interact at key tertiary contacts. These tertiary contacts correlate to high covariation contacts as identified by the statistical coupling analysis method. As these dynamic modules are exploited by various allosteric mechanisms, these tertiary contacts have been conserved by evolution.
Activation energy values from the temperature dependence of silicon PN junction reverse current and its origin
Authors: Obreja Vasile V. N. , Obreja Alexandru C.
Published: January 2010

Accurate measurements of leakage reverse current (IR) for PN junctions from silicon device samples, available at this time as commercial devices have been performed. Above 125–150 °C junction temperature, the Arrhenius plots indicate activation energy values in a range of 0.65–1.22 eV depending on the junction type. For the cellular PN junction of power MOSFET transistors, the temperature dependence indicated a value of 1.05 eV, when most of the IR flows at the junction edge (bias voltage on the gate). For zero bias on the gate, 1.22 eV has been exhibited. For the PN junction from a bipolar transistor, a value of 1.16 eV has been found in the range of 125–200 °C and 0.91 eV in the range 200–275 °C. For silicon PN junction diodes, values of 0.89 and 0.65 eV have been found. Nevertheless values higher than 1 eV can be exhibited above 125–150 °C by other diode samples. Activation energies of 1.0–1.2 eV cannot be seen as confirmation that the junction diffusion (bulk) current component is the primary component of IR. Values greater than 1 eV are possible when most of the IR flows at the junction periphery. High values of the IR at 150–200 °C junction temperature, for silicon PN junctions from commercial devices could be caused by current flow at the semiconductor dielectric interface from the junction edge and not in the bulk. Understanding and better control of junction leakage IR could enable reliable operation of silicon devices above 150–200 °C, the maximum permissible junction temperature at this time.
Angle‐resolved photoelectron spectroscopy study of hydrogen adsorption on ZnO($10\overline {1} 0$)
Authors: Ozawa K. , Mase K.
Published: January 2010

The valence electronic structure of the hydrogen adsorbed ZnO($10\overline {\rm 1} 0$) surface has been investigated by angle‐resolved photoelectron spectroscopy utilizing synchrotron radiation. Adsorption of H on ZnO($10\overline {\rm 1} 0$) at room temperature induces a state with a faint photoemission intensity at around the Fermi level. The H‐induced state forms a band with a parabolic dispersion at around the center of the surface Brillouin zone (SBZ). The band has the same energy dispersion relation along two high symmetry axes of the SBZ ($\overline {\Gamma {\rm X'}}$ and $\overline {\Gamma {\rm X}}$), i.e. the isotropic two‐dimensional electronic structure is realized. We propose the mechanism of H‐adsorption‐induced metallization of the ZnO($10\overline {\rm 1} 0$) to be a partial filling of the Zn 4s conduction band as a result of H‐induced downward band bending.
A hybrid functional scheme for defect levels and band alignments at semiconductor–oxide interfaces
Authors: Broqvist Peter , Alkauskas Audrius , Pasquarello Alfredo
Published: January 2010

We introduce a theoretical scheme to study defect energy levels and band alignments at semiconductor–oxide interfaces. The scheme relies on hybrid functionals to overcome the band gap underestimation typically achieved with semilocal density functionals. For atomically localized defects, the more accurate description achieved with hybrid functionals does not lead to significant shifts of the charge transition levels, provided these levels are referred to a common reference potential. This result effectively decouples the shifts of the band edges with respect to the defect levels. We also show that relative shifts of conduction and valence band edges as determined by exact nonlocal exchange lead to band offsets in excellent agreement with experimental values for several semiconductor–oxide interfaces. The proposed scheme is illustrated through a series of applications, including the dangling bond defects in silicon and germanium, the charge state of the O2molecule during silicon oxidation, and the oxygen vacancy in Si–SiO2–HfO2stacks.
Electronic and transport properties of graphene nanoribbons
Authors: Treske Uwe , Ortmann Frank , Oetzel Björn , Hannewald Karsten , Bechstedt Friedhelm
Published: January 2010

We perform ab initio calculations for graphene nanoribbons (GNRs) using density‐functional theory (DFT) and generalized gradient approximation (GGA) functionals. We present results for the dependence of the band structures and energy gaps on the ribbon widths for armchair and zigzag GNRs. The influence of spin polarization and spin ordering on the band structure is studied for zigzag GNRs. The electronic band structures are then converted into transmission functions using a number‐of‐states approach derived from the Landauer–Büttiker formalism. For several groups of armchair and zigzag GNRs, the similarities and differences of the quantum transport are discussed.
Application of Functional‐Link Net in QSAR. 2. QSAR for Activity Data Given by Ratings
Authors: Liu Qian , Hirono Shuichi , Moriguchi Ikuo
Published: January 2010

We devised a network with the “functional‐link net” architecture (Klassen and Pao, 1988) for QSAR for activity data given by ratings. Reference values used for training of the network were uniquely defined. In other neural networks such as the generalized delta rule net, reference values for activity ratings are usually defined by patterns using the combination of 1 and 0 so that more than one node is needed in the output layer.We, however, defined the reference by real values ranging from 0.0 to 1.0, thus, only one node sufficed in the output layer. Application of this network to QSAR of three data sets, 16 and 14 mitomycin derivatives with anticancer activity and 29 arylacryloylpiperazines with antihypertensive activity, gave good results. The comparison with other methods, such as ALS, FALS and the generalized delta rule net with back‐propagation of error, showed that our network is not only characterized by good recognition, but also by high prediction ability.
Quantitative Structure‐Activity Relationship of Histamine H2 Antagonists. Electrostatic Similarity of Cimetidine Derivatives
Authors: Nakayama Akira
Published: January 2010

The electrostatic properties of cimetidine and related histamine H2 antagonists were studied by comparing their electrostatic potentials. The charge distribution of the cyanoguanidine moiety of cimetidine was calculated by various semi‐empirical molecular orbital methods, among which the electrostatic potential (ESP) derived charges in MNDO‐PM3 method were most significantly correlated with ab initio charges of 3‐21G basis set. Using the ESP charges, electrostatic similarities of each molecule compared with the most active compound were calculated according to the definition of Carbo and Hodgkin. The similarity indices obtained for the molecules superimposed by the least square fitting method were found to correlate with the H2 antagonist activity, and the addition of logP term afforded more significant correlation, suggesting that the electrostatic similarity and lipophilicity of molecules are important for the activity. Furthermore, the superimposition of molecules to maximize the Carbo's similarity index was examined by SIMPLEX procedure. The result indicated that the superimposability both in steric and electrostatic properties is essential for the bioisosterism at the H2 receptor.
SAR of Sweet Molecules: Conformational Analysis of Two Hypersweet and Two Conformationally Restricted Aspartame Analogues
Authors: Kamphuis Johan , Lelj Francesco , Tancredi Teodorico , Toniolo Claudio , Temussi Piero A.
Published: January 2010

Our model of the active site of the sweet taste receptor, defined by means of several rigid molds, such as saccharines and naphthimidazolesulfonic acids, already consistent with many classes of rigid and flexible sweeteners, is shown to be consistent also with the so‐called hypersweet molecules, notably guanidino‐acids and arylureido‐dipeptides, and with the crystal‐state structures of two conformationally restricted analogues of aspartame, alitame and [L‐(αMe)Phe]2 aspartame, that have been recently determined.
A DFT study on the radical scavenging activity of hydroxyanthraquinone derivatives in rhubarb
Authors: Jin Ruifa , Bao Hongzheng
Published: January 2010

The structural and electronic properties of hydroxyanthraquinone derivatives in rhubarb, namely, chrysophanol, emodin, physcion, aloe‐emodin, rhein, and their radicals were investigated at density functional level. The bifurcated hydrogen bond property of the studied structures was investigated using the atoms in molecules theory. It turned out that the presence of the dihydroxy functionality increases the radical stability through hydrogen bonds formation and favors hydrogen atom abstraction. Bond dissociation energy and ionization potential were also determined to know if the radical scavenging activity of these compounds proceeds via an H‐atom or an electron‐transfer mechanism. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Ab initio study of the structure, cooperativity, and vibrational properties in the mixed hydrogen‐bonded trimers of hydrogen isocyanide and water
Authors: Li Qingzhong , Jiang Lixia , Wang Xilin , Li Wenzuo , Cheng Jianbo , Sun Jiazhong
Published: January 2010

The five trimers of H2O···HNC···H2O, H2O···H2O···HNC, HNC···H2O···H2O, H2O···HNC···HNC, and HNC···HNC···H2O have been studied with quantum chemical calculations. Their structures, harmonic vibrational frequencies and interaction energies have been calculated at the B3LYP and MP2 levels with the aug‐cc‐pVDZ and aug‐cc‐pVTZ basis sets. The cooperative effect on these properties has also been studied quantitatively. For HNC:(H2O)2systems, the cyclic H2O···H2O···HNC trimer is most stable with an interaction energy of −16.01 kcal/mol and a large cooperative energy of −3.25 kcal/mol at the MP2/aug‐cc‐pVTZ level. For H2O:(HNC)2systems, the interaction energy and cooperative energy in the H2O···HNC···HNC trimer are larger than those in the HNC···HNC···H2O trimer. The NH stretch frequency has a blue shift for the terminal HNC molecule in the HNC···H2O···H2O and HNC···HNC···H2O trimers and a red shift in other cases. A many‐body analysis has also been performed to understand the interaction energies in these hydrogen‐bonded clusters. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
A new approach to the exact and approximate anharmonic vibrational partition function of diatomic and polyatomic molecules utilizing Morse and Rosen–Morse oscillators
Authors: Toutounji Mohamad
Published: January 2010

Exact closed forms of the equilibrium partition functions in terms Jacobi elliptic functions are derived for a particle in a box and Rosen–Morse (Poschl–Teller) oscillator (perfect for modeling bending vibrational modes). An exact form of the equilibrium partition function of Morse oscillator is reported. Three other approximate forms of Morse partition function are presented. Having an exact closed‐form for the vibrational partition function can be very helpful in evaluating thermodynamic state functions, e.g., entropy, internal energy, enthalpy, and heat capacity. Moreover, the herein presented closed forms of the vibrational partition function can be used for obtaining spectroscopic and dynamical information through evaluating the two‐ and four‐point dipole moment time correlation functions in anharmonic media. Finally, a closed exact form of the rotational partition function of a particle on a ring in terms of the first kind of complete elliptic integral is derived. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Peripubertal exposure to low doses of tributyltin chloride affects the homeostasis of serum T, E2, LH, and body weight of male mice
Authors: Si Jiliang , Wu Xuesen , Wan Chengen , Zeng Tao , Zhang Miao , Xie Keqin , Li Jie
Published: January 2010

Previous studies have shown that tributyltin could act as an endocrine disruptor in mammals. However, the data on the low‐dose effect of tributyltin in animals are still lacking. The objective of this study was to demonstrate the endocrine disruption induced by low levels of tributyltin chloride (TBTCl) in male KM mice. The animals were treated with 0.05 or 0.5 mg TBTCl/kg body weight/3 days from postnatal days (PNDs) 24 to 45, and killed on PNDs 49 and 84, respectively. Mice treated with 0.5 mg TBTCl/kg exhibited decreased serum and intratesticular testosterone (T) levels on PND 49 and then followed by an obvious recovery on PND 84. Furthermore, mice treated with 0.05 mg TBTCl/kg showed reduced serum 17β‐estradiol (E2) levels on PND 49. However, treatments with TBTCl resulted in a dose‐dependent increase in serum E2 concentration of the mice on PND 84. Administration of TBTCl also decreased levels of serum luteinizing hormone and intratesticular E2 on PND 84. In addition, mice exposed to 0.05 mg/kg TBTCl exhibited an increase in body weight in the late stage of the experiment. These results indicate that treatment with low doses of TBTCl could disturb hormone homeostasis and body weight gain in rodents, and exposure to different levels of TBTCl might have different effects on changing some physiologic parameters. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2011.
Expectant management of spontaneous first‐trimester miscarriage: prospective validation of the ‘2‐week rule’
Authors: Casikar I. , Bignardi T. , Riemke J. , Alhamdan D. , Condous G.
Published: January 2010

Objectives

To assess uptake and success of expectant management of first‐trimester miscarriage for a finite 14‐day period, in order to evaluate our ‘2‐week rule’ of management.

Methods

This was a prospective observational study evaluating our proposed 2‐week rule of expectant management, which is based on the finding that women managed expectantly are most likely to miscarry in the first 14 days and that to wait longer than 2 weeks without intervention does not confer a greater chance of successful resolution. Eligible women diagnosed with first‐trimester miscarriage were offered a choice of expectant management or surgical evacuation under general anesthesia. Inclusion criteria for expectant management were: diagnosis of incomplete miscarriage (heterogeneous tissue, with or without a gestational sac, seen on ultrasound in the uterine cavity and distorting the endometrial midline echo), missed miscarriage (crown–rump length (CRL) ≥ 6 mm with absent fetal heart activity) or empty sac (anembryonic pregnancy) based on transvaginal ultrasonography. Women with complete miscarriage, missed miscarriage at the nuchal translucency scan, molar pregnancy or miscarriage ≥ 3 weeks in duration (missed miscarriage in which the CRL was ≥ 3 weeks smaller than the gestational age based on last menstrual period), or with signs of infection or hemodynamic instability were excluded. Expectant management consisted of weekly ultrasonography for 2 weeks. If after 2 weeks resolution was not complete, surgery was advised.

Results

1062 consecutive pregnant women underwent transvaginal ultrasound examination. Of these, 38.6% (410/1062) were diagnosed with miscarriage, of whom 241 (59%) were symptomatic at the time of presentation and 282 were eligible for the study. These were offered expectant management and 80% (227/282) took up this option. 11% (24/227) were lost to follow‐up; therefore, complete data were available on 203 women. Overall spontaneous resolution of miscarriage at 2 weeks was observed in 61% (124/203) of women. Rates of spontaneous resolution at 2 weeks according to the type of miscarriage were 71% for incomplete miscarriage, 53% for empty sac and 35% for missed miscarriage. The incidence of unplanned emergency dilatation and curettage due to gynecological infection or hemorrhage was 2.5% (5/203).

Conclusions

Expectant management based on the 2‐week rule is a viable and safe option for women with first‐trimester miscarriage. Women with an incomplete miscarriage are apparently the most suitable for expectant management. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Umbilical vein anomaly in fetuses with Down syndrome
Authors: Achiron R. , Gindes L. , Gilboa Y. , Weissmann‐Brenner A. , Berkenstadt M.
Published: January 2010

Objective

To describe the prevalence of abnormal umbilical vein (UV) anatomy in fetuses with Down syndrome.

Methods

This was a retrospective survey covering a 24‐month period of fetuses with a genetic diagnosis of Down syndrome following a routine early second‐trimester (12–16‐week) detailed fetal anomaly scan at a single academic tertiary referral center. In our unit this exam includes fetal umbilicoportal venous system evaluation.

Results

During the study period, 37 fetuses were diagnosed with Down syndrome and had a detailed early anatomy scan. In four (11%) the detailed early anomaly scan revealed that the UV was connected to the hepatic portion of the inferior vena cava (IVC) at a position lower than its usual site. Their average gestational age at diagnosis was 13 + 6 (range, 11 + 6 to 15 + 2) weeks. Three of the four fetuses had a nuchal translucency thickness of 3–4 mm. In one fetus there was an additional finding of significant tricuspid regurgitation and the one with normal nuchal translucency thickness had an atrioventricular septal defect (atrioventricular canal) and umbilical cord hernia. During the same period three of 2500 (0.12%) fetuses with normal karyotype demonstrated similar anomalous insertion of the UV into the IVC, creating a portocaval shunt which had normal ductus venosus‐like Doppler flow in all three cases. The odds ratio for abnormal umbilicoportal venous system in fetuses with Down syndrome compared with the normal population was 107.4 (95% CI, 19.2–637.1).

Conclusions

Fetuses with Down syndrome demonstrate an increased prevalence of abnormal connection of the UV to the IVC. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Continuous independent quality control for fetal ultrasound biometry provided by the cumulative summation technique
Authors: Balsyte D. , Schäffer L. , Burkhardt T. , Wisser J. , Zimmermann R. , Kurmanavicius J.
Published: January 2010

Objective

To apply the cumulative summation (CUSUM) technique for an evaluation of the learning process of sonographic fetal weight estimation at term in combination with the z‐scores of biometry determinants and to assess the time of appearance and sources of errors.

Methods

Learning curve (LC‐CUSUM) and double CUSUM charts for systematic error detection based on absolute and signed mean percentage error were generated to retrospectively estimate the longitudinal accuracy of sonographic fetal weight estimation conducted by three trainees and one experienced examiner. For LC‐CUSUM analysis an examination was considered to be a failure when there was an absolute error in birth weight estimation ≥ 15%. Fetal biometry measurements (head circumference, abdominal circumference (AC) and femur length (FL)) from 227 routine ultrasound scans of one examiner were separately transformed into z‐scores and double CUSUM charts were generated to assess the systematic errors for each determinant.

Results

The LC‐CUSUM charts revealed that different numbers of scans are required for different examiners to achieve competence in estimating birth weight. AC and FL deviated most significantly from expected values (P < 0.05). The double CUSUM charts revealed exact periods of systematic errors in the measurement of biometry determinants, clearly reflecting errors of fetal weight estimation.

Conclusions

The use of CUSUM techniques in the analysis of sonographic data allows observation of the development of an examiner's skill and maintenance of competence. The CUSUM technique not only allows the reasons for impaired fetal weight estimation to be revealed but also allows determination of the exact time when inaccurate measurements start to occur. We suggest that CUSUM charts should be implemented in routine clinical practice as a measure of objective quality evaluation of sonographic fetal biometry. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Three‐dimensional ultrasound in the diagnosis of Müllerian duct anomalies and concordance with magnetic resonance imaging
Authors: Bermejo C. , Martínez Ten P. , Cantarero R. , Diaz D. , Pérez Pedregosa J. , Barrón E. , Labrador E. , Ruiz López L.
Published: January 2010

Objectives

To demonstrate the value of three‐dimensional (3D) ultrasound in the diagnosis of uterine malformations and its concordance with magnetic resonance imaging (MRI).

Methods

This study included 286 women diagnosed with uterine malformation by 3D ultrasound, having been referred to our clinics on suspicion of uterine malformation following clinical and/or conventional two‐dimensional ultrasound examination. With the exception of three with intact hymen, patients underwent both bimanual examination and speculoscopy before and/or after sonography. MRI was performed in 65 cases. We analyzed the diagnostic concordance between the techniques in the study of uterine malformations.

Results

Using 3D ultrasound we diagnosed: one case with uterine agenesis; 10 with unicornuate uterus, four of which also underwent MRI; six with didelphic uterus, one of which had MRI; 45 with bicornuate uterus, 12 of which had MRI; 125 with septate uterus (18 with two cervices), 42 of which had MRI (six with two cervices); 96 with arcuate uterus, three of which had MRI; and three with diethylstilbestrol (DES) iatrogenic uterine malformations, all of which had MRI. Among the 65 which underwent MRI, the diagnosis was: four cases with unicornuate uterus, 10 with bicornuate uterus (two with two cervices), 45 with septate uterus (five with two cervices), three with arcuate uterus and three with DES‐related uterine malformations. The concordance between 3D ultrasound and MRI was very good (kappa index, 0.880 (95% CI, 0.769–0.993)). Discrepancies in diagnosis between the two techniques occurred in four cases. There was very good concordance in the diagnosis of associated findings (kappa index, 0.878 (95% CI, 0.775–0.980)), this analysis identifying differences in two cases.

Conclusions

There is a high degree of concordance between 3D ultrasound and MRI in the diagnosis of uterine malformations, the relationship between cavity and fundus being visualized equally well with both techniques. 3D ultrasound should be complemented by careful gynecological exploration in order to identify any alterations in the cervix. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Invasive growth of Saccharomyces cerevisiae depends on environmental triggers: a quantitative model
Authors: Zupan Jure , Raspor Peter
Published: January 2010

In this contribution, the influence of various physicochemical factors on Saccharomyces cerevisiae invasive growth is examined quantitatively. Agar‐invasion assays are generally applied for in vitro studies on S. cerevisiae invasiveness, the phenomenon observed as a putative virulence trait in this clinically more and more concerning yeast. However, qualitative agar‐invasion assays, used until now, strongly limit the feasibility and interpretation of analyses and therefore needed to be improved. Besides, knowledge in this field concerning the physiology of invasive growth, influenced by stress conditions related to the human alimentary tract and food, is poor and should be expanded. For this purpose, a quantitative agar‐invasion assay, presented in our previous work, was applied in this contribution to clarify the significance of the stress factors controlling the adhesion and invasion of the yeast in greater detail. Ten virulent and non‐virulent S. cerevisiae strains were assayed at various temperatures, pH values, nutrient starvation, modified atmosphere, and different concentrations of NaCl, CaCl2 and preservatives. With the use of specific parameters, like a relative invasion, eight invasive growth models were hypothesized, which enabled intelligible interpretation of the results. A strong preference for invasive growth (meaning high relative invasion) was observed when the strains were grown on nitrogen‐ and glucose‐depleted media. A significant increase in the invasion of the strains was also determined at temperatures typical for human fever (37–39 °C). On the other hand, a strong repressive effect on invasion was found in the presence of salts, anoxia and some preservatives. Copyright © 2010 John Wiley & Sons, Ltd.
Lymph Node Ratio Versus Number of Affected Lymph Nodes as Predictors of Survival for Resected Pancreatic Adenocarcinoma
Authors: Bhatti Imran , Peacock Oliver , Awan Altaf K. , Semeraro David , Larvin Michael , Hall Richard I.
Published: January 2010

Background

The objective of this study was to compare the prognostic significance of the lymph node ratio (LNR) with the absolute number of affected lymph nodes for resected pancreatic ductal adenocarcinoma.

Methods

Data were collected from 84 patients who had undergone pancreatoduodenectomy for pancreatic ductal adenocarcinoma over a 10‐year period. Patients were categorized into four groups according to the absolute LNR (0, 0–0.199, 0.2–0.299, ≥0.3). Kaplan‐Meier and Cox proportional hazard models were used to evaluate the prognostic effect.

Results

An LNR of ≥0.2 (median survival 8.1 vs. 35.7 months with LNR < 0.2; p < 0.001) and ≥0.3 (median survival 5.9 vs. 29.6 months with LNR < 0.3; p < 0.001), tumor size (p < 0.017), positive resection margin (p < 0.001), and nodal involvement (p < 0.001) were found to be significant prognostic markers following univariate analysis. Following multivariate analysis, only LNR at both levels [≥0.2 (p = 0.05; HR 1.8) and LNR of ≥0.3 (p = 0.01; HR 2.7)] were independent predictors of a poor outcome. The number of lymph nodes examined had no effect on overall survival in either node‐positive patients (p = 0.339) or node‐negative patients (p = 0.473).

Conclusions

The LNR represents a stronger independent prognostic indicator than the absolute number of affected lymph nodes in patients with resected pancreatic ductal adenocarcinoma.
Hunter syndrome in an 11‐year old girl on enzyme replacement therapy with idursulfase: brain magnetic resonance imaging features and evolution
Authors: Manara Renzo , Rampazzo Angelica , Cananzi Mara , Salviati Leonardo , Mardari Rodica , Drigo Paola , Tomanin Rosella , Gasparotto Nicoletta , Priante Elena , Scarpa Maurizio
Published: January 2010

Mucopolysaccharidosis type II (MPS‐II, Hunter disease) is a X‐linked recessive disorder. Affected females are extremely rare, mostly due to skewed X chromosome inactivation. A few papers outline MPS‐II brain magnetic resonance imaging (MRI) “gestalt” in males, but neuroradiological reports on females are still lacking. We present an 11‐year‐old girl affected by the severe form of MPS‐II who was followed up over a time span of 8 years, focusing on clinical and brain MRI evolution. In the last 2.5 years, the patient has been treated with enzyme replacement therapy (ERT) with idursulfase (Elaprase™, Shire Human Genetic Therapies AB, Sweden). On brain and cervical MRI examination, abnormalities in our patient did not differ from those detected in male patients: J‐shaped pituitary sella, enlargement of perivascular spaces, brain atrophy, mild T2‐hyperintensity in the paratrigonal white matter, diffuse platyspondylia, and mild odontoid dysplasia with odontoid cup. Brain atrophy progressed despite ERT introduction, whereas perivascular space enlargement did not change significantly before and after ERT. Cognitive impairment worsened independently from the course of white matter abnormality. Despite a profound knowledge of genetic and biochemical aspects in MPS‐II, neuroradiology is still poorly characterized, especially in female patients. Spinal and brain involvement and its natural course and evolution after ERT introduction still need to be clarified.