bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multifunctional Nanoscale Platforms for Targeting of the Cancer Cell Immortality Spectrum
Authors: Soundararajan Venkataramanan , Warnock Kenneth , Sasisekharan Ram 
Published: January 2010

AbstractIn 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.magnified image
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

AbstractPoly(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.magnified image
Advances in the Elegance of Chemistry in Designing Dendrimers
Authors: Hourani Rami , Kakkar Ashok 
Published: January 2010

AbstractHighly 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.magnified image
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

AbstractIn 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.magnified image
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

AbstractBackgroundTo describe trends in cancer incidence and mortality among children less than 15 years of age in urban Shanghai between 1973 and 2005.ProcedureAnnual 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.ResultsFor 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%).ConclusionsChildhood 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

AbstractEhrlichiosis, 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

AbstractSingle‐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

AbstractAccurate 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

AbstractThe 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

AbstractWe 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

AbstractWe 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

AbstractWe 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

AbstractThe 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

AbstractOur 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

AbstractThe 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

AbstractThe 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

AbstractExact 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

AbstractPrevious 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.