bluuebunny/crossref_metadata_2025 huggingface dataset:
Making the diagnosis with only two levels of nongynecologic cell blocks as opposed to three is more cost effective
Authors: Zanchelli‐Astran Gina , Wood Moira , Bibbo Marluce
Published: March 2010

Two hundred forty‐three of 246 cases in phase I (98.8%) and 246 of 247 cases in phase II (99.6%) had adequate or the same material present on the level two cell blocks. Sixty‐nine cases were malignant (28.1%), 20 were atypical (8.1%), 157 were benign (63.8), and 16 were signed out on the cell block only (6.5%) in phase I. In phase II, 69 (27.9%) cases were malignant, 22 (8.9%) were atypical, 156 (63.2%) were benign, and 18 (7.3%) were signed out based on material present in the cell block. Fifteen cases in phase I (6.1%) and 17 (6.9%) in phase II needed immunohistochemical staining for further evaluation. Twenty‐four upper urinary tract (UUT) cases were signed out as malignant (49.0%), 10 were atypical (20.4%), and 15 were benign (30.6%) in phase I. In phase II, 18 (56.3%) UUT were malignant, 8 (25.0%) were atypical, and 6 (18.7%) were benign. In phase I, 13 (26.5%) and in phase II, 18 (56.3%) were graded on the cell block only. On comparing the two phases, there was no significant difference in the amount of diagnostic material present between the level three and level two cell blocks (98.8% and 99.6%, respectively) or the number of cases diagnosed based on the cell block (6.5% and 7.3%, respectively). Cases signed out as malignant, atypical, and benign were similar in both phases. Likewise, the cases that required immunohistochemical staining to aid in the diagnosis between phase one and phase two were similar (6.1% and 6.9%, respectively). respectively). Diagn. Cytopathol. 2010. © 2010 Wiley‐Liss, Inc.
Papanicolaou stain may not be necessary in majority of head and neck fine‐needle aspirations: Evidence from a correlation study between diff–quik‐based onsite diagnosis and final diagnosis in 287 head and neck fine‐needle aspirations
Authors: Wu Maoxin , Idrees Muhammad , Zhang Zhengbin , Genden Eric , Burstein David E.
Published: March 2010

Fine‐needle aspiration (FNA) is a useful tool for immediate assessment of palpable lesions, especially in the head and neck region. The objective of this study is to evaluate the degree of correlation between Diff–Quik‐based onsite diagnosis (OD) and final diagnosis (FD) and further improve the efficiency of FNA practice.

Two hundred and eighty‐seven cytopathologist‐performed FNAs from the head and neck region were evaluated. Number of passes, number and type of slides and correlation (agreement, modified final diagnosis and disagreement) between OD and FD were evaluated.

Among 287 FNAs, the average number of passes per FNA case was 2 (range, 1–5&.rpar;). The mean number of slides reviewed per case was 5 including 2 Diff–Quik (D–Q)‐stained slides, 2 Papanicolaou (Pap)‐stained slides, and 1 cell block (CB)/1 cytospin (Cy). 247 of 287 (86%) cases showed agreement between OD and FD. FD on 36 out of 287 cases (12.5%) was slightly modified or refined after reviewing additional slides. A major diagnostic discrepancy was noted in four cases (1.5%), three of which were classified as squamous cell carcinoma on final diagnosis, and confirmed on surgical follow‐up.

Accurate diagnosis can be achieved in the majority (86%) of head and neck FNAs based on immediate examination of D–Q stained slides alone. In a small number of cases (12.5%), reviewing additional slides may refine the final diagnosis. In rare cases, especially cystic squamous lesions, Pap‐stained slides appeared to be helpful. It is plausible to use D–Q‐stained slides alone with most head and neck FNAs in order to provide more cost effective and efficient triaging and patient management. Diagn. Cytopathol. 2010;38:846–853. © 2010 Wiley‐Liss, Inc..
Cytopathological features of warty (condylomatous) carcinoma of the penis: A case report and distinction from other verruciform penile tumors
Authors: Hayashi Toshitetsu , Haba Reiji , Kushida Yoshio , Kadota Kyuichi , Katsuki Naomi , Miyai Yumi , Bando Kenji , Shibuya Shinsuke , Funamoto Yasunobu , Kakehi Yoshiyuki
Published: March 2010

Warty (condylomatous) carcinoma (WC) is a rare specific variant of invasive squamous cell carcinoma that shows hybrid features of condyloma with invasive cell carcinoma. As compared with conventional squamous cell carcinoma, WC tends to run a less aggressive clinical course. A case is presented here in which squash smears of a penile foreskin tumor in a 65‐year‐old male revealed small cohesive clusters and sheets of tumor cells in papillary configurations. The neoplastic cells were polygonal to elongated and contained oval nuclei, coarse chromatin pattern, and distinct nucleoli. Nuclear pleomorphism and loss of nuclear polarity were observed. Characteristically, there were also many koilocytes demonstrating mild to moderate nuclear atypia and perinuclear cytoplasmic halos. A cytologic diagnosis of a verruciform penile tumor was suggested. Histologic examination of the tumor showed a hyper‐parakeratotic arborizing papillomatous growth with thin fibrovascular cores and the tips were variably rounded or tapered. Obvious koilocytic cytopathic change, nuclear pleomorphism, and focal stromal invasion were observed. Immunohistochemically, the tumor cells showed diffuse and strong membranous staining for cytokeratin (AE1/AE3) while the MIB‐1 and p53 immunoreactive cells were confined to the basal areas of the papillae. No lymphovascular invasion was detected in D2‐40 or elastic Van‐Gieson stains. On the basis of the overall features, we confirmed a final diagnosis of penile WC. We demonstrated here for the first time the cytopathological features of penile WC with emphasis on differential diagnostic considerations. Diagn. Cytopathol. 2010;38:841–845. © 2010 Wiley‐Liss, Inc.
Helminth‐induced CD19+CD23hi B cells modulate experimental allergic and autoimmune inflammation
Authors: Wilson Mark S. , Taylor Matthew D. , O'Gorman Mary T. , Balic Adam , Barr Tom A. , Filbey Kara , Anderton Stephen M. , Maizels Rick M.
Published: March 2010

Numerous population studies and experimental models suggest that helminth infections can ameliorate immuno‐inflammatory disorders such as asthma and autoimmunity. Immunosuppressive cell populations associated with helminth infections include Treg and alternatively‐activated macrophages. In previous studies, we showed that both CD4+CD25+ Treg, and CD4– MLN cells from Heligmosomoides polygyus‐infected C57BL/6 mice were able to transfer protection against allergic airway inflammation to sensitized but uninfected animals. We now show that CD4–CD19+ MLN B cells from infected, but not naïve, mice are able to transfer a down‐modulatory effect on allergy, significantly suppressing airway eosinophilia, IL‐5 secretion and pathology following allergen challenge. We further demonstrate that the same cell population can alleviate autoimmune‐mediated inflammatory events in the CNS, when transferred to uninfected mice undergoing myelin oligodendrocyte glycoprotein(p35–55)‐induced EAE. In both allergic and autoimmune models, reduction of disease was achieved with B cells from helminth‐infected IL‐10−/− donors, indicating that donor cell‐derived IL‐10 is not required. Phenotypically, MLN B cells from helminth‐infected mice expressed uniformly high levels of CD23, with follicular (B2) cell surface markers. These data expand previous observations and highlight the broad regulatory environment that develops during helminth infections that can abate diverse inflammatory disorders in vivo.
Identification of the rat NKG2D ligands, RAE1L and RRLT, and their role in allograft rejection
Authors: Zhuo Ming , Fujiki Masato , Wang Mouer , Piard‐Ruster Karine , Wai Lu‐En , Wei Liang , Martinez Olivia M. , Krams Sheri M.
Published: March 2010

NKG2D is a receptor expressed by NK cells and subsets of T lymphocytes. On NK cells, NKG2D functions as a stimulatory receptor that induces effector functions. We cloned and expressed two rat NKG2D ligands, both members of the RAE1 family, RAE1L and RRLT, and demonstrate that these ligands can induce IFN‐γ secretion and cytotoxicity by rat NK cells. To examine changes in expression of NKG2D and the NKG2D ligands RAE1L and RRLT after transplantation, we used a Dark Agouti (DA)→Lewis rat model of liver transplantation. NKG2D expression was significantly increased in allogeneic liver grafts by day 7 post‐transplant. Ligands of NKG2D, absent in normal liver, were readily detected in both syngeneic and allogeneic liver grafts by day 1 post‐transplant. By day 7 post‐transplant, hepatocyte RAE1L and RRLT expression was significantly and specifically increased in liver allografts. In contrast to acute rejection that develops in the DA→Lewis model, transplantation of Lewis livers into DA recipients (Lewis→DA) results in spontaneous tolerance. Interestingly, expression of RAE1L and RRLT is low in Lewis→DA liver allografts, but significantly increased in DA→Lewis liver allografts undergoing rejection. In conclusion, our results suggest that expression of NKG2D ligands may be important in allograft rejection.
Divergent roles of Toll‐like receptor 2 in response to lipoteichoic acid and Staphylococcus aureus in vivo
Authors: Gillrie Mark R. , Zbytnuik Lori , McAvoy Erin , Kapadia Roxna , Lee Kristine , Waterhouse Christopher C. M. , Davis Shevaun P. , Muruve Daniel A. , Kubes Paul , Ho May
Published: March 2010

The response of leukocytes to lipoteichoic acid (LTA), a TLR2‐dependent major cell wall component of Staphylococcus aureus, is linked to the outcome of an infection. In this study we investigated the role of nonhematopoietic TLR2 in response to LTA and S. aureus by creating bone marrow chimeras. Significant leukocyte recruitment in response to LTA required IFN‐γ priming in WT C57BL/6 and TLR2−/−⇒WT mice, but was not observed in TLR2−/− or WT⇒TLR2−/− animals. LTA also induced a proinflammatory response in IFN‐γ primed primary human microvascular endothelial cells leading to leukocyte recruitment in vitro. When mice were infected with S. aureus, the most profound elevation of TNF‐α and IL‐6 was seen in TLR2−/− and TLR2−/−⇒WT mice. TLR2−/−, but not chimeric mice, demonstrated increased IL‐17, blood leukocytosis and pulmonary neutrophilia compared to WT mice. Collectively, the results suggest an essential role for IFN‐γ and nonhematopoietic TLR2 for leukocyte recruitment in response to LTA. In contrast, TLR2 on both hematopoietic and nonhematopoietic cells appears to orchestrate an inhibitory response to S. aureus such that in complete TLR2 deficiency, there is an exaggerated proinflammatory response and/or skewing of the immune response towards a Th17 phenotype that may contribute to the decreased survival of TLR2−/− mice.
CD8+ NK cells are predominant in chimpanzees, characterized by high NCR expression and cytokine production, and preserved in chronic HIV‐1 infection
Authors: Rutjens Erik , Mazza Stefania , Biassoni Roberto , Koopman Gerrit , Ugolotti Elisabetta , Fogli Manuela , Dubbes Rob , Costa Paola , Mingari Maria C. , Greenwood Edward J. D. , Moretta Lorenzo , DeMaria Andrea , Heeney Jonathan L.
Published: March 2010

HIV‐1 infection in humans results in an early and progressive NK cell dysfunction and an accumulation of an “anergic” CD56− CD16+ NK subset, which is characterised by low natural cytotoxicity receptor expression and low cytokine producing capacity. In contrast to humans, chimpanzee NK cells do not display a distinguishable CD56bright and CD56dim subset but, as shown here, could be subdivided into functionally different CD8+ and CD8− subsets. The CD8+ NK cells expressed significantly higher levels of triggering receptors including NKp46 and, upon in vitro activation, produced more IFN‐γ, TNF‐α and CD107 than their CD8− counterparts. In addition, chimpanzee CD8− NK cells had relatively high levels of HLA‐DR expression, suggestive of an activated state. Killing inhibitory receptors were expressed only at low levels; however, upon in vitro stimulation, they were up‐regulated in CD8+ but not in CD8− NK cells and were functionally capable of inhibiting NKp30‐triggered killing. In contrast to HIV‐1‐infected humans, infected chimpanzees maintained their dominant CD8+ NK cell population, with high expression of natural cytotoxicity receptors.
Surfactantless Synthesis and the Surface‐Enhanced Raman Spectra and Catalytic Activity of Differently Shaped Silver Nanomaterials
Authors: Li Xuanhua , Wang Jin , Zhang Yongxing , Li Mingqiang , Liu Jinhuai
Published: March 2010

This paper reports the transition of shape‐selective silver nanostructures from nanoplates to nanodendrites and to nanospheres made up of primary nanoparticles that can be readily controlled by changing the molar ratio of vitamin C to AgNO3. In addition, the formation of Ag nanostructures with multiple shapes can be readily controlled depending on the efficient density‐assisted self‐assembly synthesis. The surface‐enhanced effects and catalytic activity of the formed Ag nanomaterials are strongly dependent on the surface morphologies of Ag nanomaterials, and compared with the other Ag nanomaterials presented here, the nanospheres made up of primary nanoparticles showed excellent surface‐enhanced effects and catalytic activity.
A Facile Approach to Fabrication of Hexagonal‐Phase NaYF4:Yb3+, Er3+ Hollow Nanospheres: Formation Mechanism and Upconversion Luminescence
Authors: Zhao Junwei , Liu Xiaomin , Cui Di , Sun Yajuan , Yu Yi , Yang Yifei , Du Chuang , Wang Yu , Song Kai , Liu Kai , Lu Shaozhe , Kong Xianggui , Zhang Hong
Published: March 2010

The hexagonal‐phase NaYF4:Yb3+, Er3+ hollow nanospheres (HNS) have been successfully prepared for the first time by means of a hydrothermal route with the aid of polyethylenimine (PEI) as a surfactant. The nitrogen adsorption/desorption isotherms demonstrated the porous nature of the NaYF4 HNS. The formation mechanism was explored based on the effects of the reaction parameters. The NaYF4 solid spheres underwent a dissolution‐recrystallisation transformation and a hollowing process when the hydrothermal reaction time was prolonged. The localised Ostwald ripening mechanism was proposed to account for the formation of NaYF4 HNS, in which loose aggregations were found to be crucial. The upconversion luminescence of NaYF4:Yb3+, Er3+ HNS was also investigated. It is expected that these NaYF4 HNS might have potential in applications as building blocks for biolabels and drug‐delivery.
Thermal Decomposition Reactions as a Tool for the Synthesis of New Thermodynamic Metastable Modifications: Synthesis, Structures, and Properties of (Formato)nickel(II) Coordination Polymers Based on 4,4′‐Bipyridine
Authors: Boeckmann Jan , Wriedt Mario , Näther Christian
Published: March 2010

The reaction of nickel formate with 4,4′‐bipyridine (bipy) in aqueous solution at room temperature leads to the formation of the hydrated compound [Ni(HCO2)2(H2O)(bipy)·4H2O]n (1) reported recently. On heating, compound 1 decomposes into the new anhydrous compound of composition [Ni(HCO2)2(bipy)]n (2II), which decomposes on further heating. Interestingly, if the anhydrous compound is prepared from solution, a new modification 2I is obtained. Investigations on the stability of both forms show that modification 2I presents the thermodynamically most stable form between room and decomposition temperature, whereas modification 2II, which can only be prepared by thermal decomposition, is metastable. In the crystal structure of 2I, the Ni2+ cations are coordinated by four μ2‐anti,anti bridging formato anions and two bridging μ2‐bipy ligands in a slightly distorted octahedralgeometry. The formato anions bridge the metal cations in zigzag chains, which are further connected by μ2‐anti,anti formato anions and bipy ligands to give a three‐dimensional coordination network. IR spectroscopic investigations on the metastable form 2II also indicate that all formato anions act as bridging ligands. Magnetic measurements of the hydrated and anhydrous compounds reveal different behavior with a ferromagnetic ordering for compound 2I and an antiferromagnetic ordering for compound 1. For form 2II, only Curie–Weiss paramagnetism was found.
Synthesis, Structure, and Magnetic Properties of Amine‐Templated Transition‐Metal Phosphites
Authors: Ramaswamy Padmini , Mandal Sukhendu , Hegde Nayana N , Prabhu Ramanath , Banerjee Debmalya , Bhat S. V. , Natarajan Srinivasan
Published: March 2010

Transition‐metal phosphites of cobalt and vanadium, [C4N2H12][Co(HPO3)2] (I), [C4N2H14][Co(HPO3)2] (II), [Co(C10H8N2)(H2PO3)2] (III), [C4N2H14][VIIIF(HPO3)2]·H2O (IV), and [C3N2H5]2[V4III(H2O)3(HPO3)4(HPO4)3] (V), have been synthesized and characterized. Organophosphorus esters were employed to stabilize cobalt in tetrahedral coordination and also to prepare the low‐dimensional structures, which are otherwise difficult to synthesize. The structures have one‐ (I, II, IV), two‐ (III) and three‐dimensionally (V) extended networks built up by the linking of metal polyhedra and phosphite units. Another vanadyl phosphite, [C2N2H10][(VIVO)3(H2O)(HPO3)4]·H2O,15 was also prepared and investigated extensively by ESR, magnetic susceptibility, and other studies. All the compounds in the present study exhibit antiferromagnetic interactions. Well‐established magnetic models have been used to fit the experimental data. The compounds have also been characterized in detail by using UV/Vis spectroscopic studies.
[Bis(pyrazolyl)methane]palladium Complexes with a Carbosilane Dendritic Structure
Authors: Sánchez‐Méndez Alberto , de Jesús Ernesto , Flores Juan C. , Gómez‐Sal Pilar
Published: March 2010

A series of carbosilane dendritic ligands of general formula Gn‐[CH(3,5‐Me2pz)2]m and their corresponding palladium(II) complexes Gn‐[CH(3,5‐Me2pz)2Pd(X)Cl]m (X = Cl or Me) containing four (m = 1) or eight (m = 2) terminal bis(pyrazolyl)methane moieties, along with their corresponding monometallic counterparts (m = 0), have been synthesized. An appropriate choice of poly(pyrazolyl)methane ligand has allowed us to overcome the steric and solubility issues that previously limited the synthesis of polymetallic dendrimers containing (scorpionato)palladium complexes. The evaluation of these complexes as catalyst precursors in the Heck reaction between p‐iodotoluene and methyl acrylate is also reported.
Synthesis, NMR, and Conformational Studies of Cyclic Oligo‐(1→6)‐β‐D‐Glucosamines
Authors: Gening Marina L. , Titov Denis V. , Grachev Alexey A. , Gerbst Alexey G. , Yudina Olga N. , Shashkov Alexander S. , Chizhov Alexander O. , Tsvetkov Yury E. , Nifantiev Nikolay E.
Published: March 2010

The first synthesis of a series of homologous cyclic oligo‐(1→6)‐β‐D‐glucosamines consisting of two to seven residues and representing a new type of functionalized cyclic oligosaccharides is reported. Remarkably high yields of the studied macrocyclization reaction irrespective of the length of the acyclic precursors were observed. In the case of compounds constituted of four to seven glucosamine units α‐stereoisomers formed as side products despite the presence of a strongly participating 2‐N‐phthaloyl group to control β‐glycosylation. Both phenomena may be accounted for by conformational features of the linear bifunctional precursors. According to computer modeling and NMR conformational studies, the described linear (1→6)‐β‐linked oligoglucosamines exist in a right‐handed helix‐like conformation, in which the glycosyl donor and acceptor moieties are prearranged in a way that facilitates intramolecular glycosylation from the α‐side. Prepared cyclo‐oligoglucosamines differ in their conformational flexibilities, as illustrated by their spectral characteristics and calculated asphericity distributions. Moreover, the obtained compounds do not possess a distinct hydrophobic cavity, which is in contrast to the well‐known cyclodextrins. All these characteristics provide an excellent basis for the use of these novel cyclic oligosaccharides as scaffolds for the construction of biomolecular conjugates.
Solid‐Phase Synthesis of Aza‐Kahalalide F Analogues: (2R,3R)‐2‐Amino‐3‐azidobutanoic Acid as Precursor of the Aza‐Threonine
Authors: Izzo Irene , Acosta Gerardo A. , Tulla‐Puche Judit , Cupido Tommaso , Martin‐Lopez Maria Jesus , Cuevas Carmen , Albericio Fernando
Published: March 2010

The solid‐phase synthesis of six novel analogues of Kahalalide F (KF), a natural product currently undergoing Phase II clinical trials, is reported. In all these compounds, amides were used as isosteres for the depsi bond. For two of these compounds, we performed an efficient synthesis of N‐Fmoc‐protected (2R,3R)‐2‐amino‐3‐azidobutanoic acid, precursor of the aza‐threonine. This is the first example of the solid‐phase reduction of an azide group in the preparation of aza‐Thr‐containing peptides in the solid phase.
Esterification of Maleamic Acids without Double Bond Isomerization
Authors: Sánchez Albert , Pedroso Enrique , Grandas Anna
Published: March 2010

Activation of the carboxylic acid group of a maleamic acid by treatment with an arenesulfonyl chloride followed by addition of an alcohol affords a fumaramate or a maleamate, depending on the reaction conditions. The E isomer is obtained when the acid is treated with nearly equimolar amounts of 2,4,6‐triisopropylbenzenesulfonyl chloride and an alcohol in pyridine. Replacement of pyridine by 2‐picoline and use of a larger excess of activating agent (mesitylenesulfonyl chloride) and alcohol affords the Z isomer. In both cases, high diastereomeric excesses and yields are achieved.
Chiral and Achiral Charge‐Transfer Chromophores with a Dendralene‐Type Backbone by Electronically Controlled Cycloaddition/Cycloreversion Cascades
Authors: Frank Brian B. , Kivala Milan , Camafort Blanco Berta , Breiten Benjamin , Schweizer W. Bernd , Laporta Philip R. , Biaggio Ivan , Jahnke Eike , Tykwinski Rik R. , Boudon Corinne , Gisselbrecht Jean‐Paul , Diederich François
Published: March 2010

Chiral and achiral push‐pull chromophores have been prepared by cascades of sequential [2+2] cycloadditions of tetracyanoethene (TCNE) and tetrathiafulvalene (TTF) to different oligoynes. Thermal [2+2] cycloaddition of TCNE to donor‐substituted alkynes, followed by electrocyclic ring‐opening of the initially formed cyclobutenes, affords donor‐substituted 1,1,4,4‐tetracyanobuta‐1,3‐dienes (TCBDs). Similarly, TTF reacts with electron‐deficient C≡C bonds to give the corresponding buta‐1,3‐diene derivatives, 1,2‐bis(1,3‐dithiol‐2‐ylidene)ethanes. Thus, achiral [AB]‐type oligomers were synthesized from N,N‐dialkylanilino (DAA)‐substituted tetraynes and hexaynes and chiral [AB]‐type oligomers from alkyne‐substituted 1,1′‐binaphthalenes. The [AB]‐type oligomers exhibit complex conformational equilibria in solution, as revealed by 1H and 13C NMR spectroscopy. Therefore, the circular dichroism (CD) spectra of the chiral [AB]‐type oligomers were measured to investigate whether a preferred conformation of the dendralene‐type backbone is induced by the optically active 1,1′‐binaphthalene moiety. Electrochemical studies by cyclic voltammetry (CV) and rotating‐disk voltammetry (RDV) showed large cathodic shifts of the first oxidation potentials for some of the chiral and achiral [AB]‐type oligomers due to sterically enforced π‐deconjugation of the acceptor and donor moieties. The new multivalent systems feature intense, bathochromically shifted intramolecular charge‐transfer (CT) bands in the UV/Vis spectra. Extended, donor‐substituted TCBDs, which are obtained by mono‐addition of TCNE to the hexaynes, exhibit low optical and electrochemical HOMO–LUMO gaps. In addition, a large third‐order optical nonlinearity was measured for one of these TCBDs by degenerate four‐wave mixing (DFWM).
Asymmetric Synthesis of (1,3‐Butadien‐2‐yl)methanols from Aldehydes via [1‐(Silylmethyl)allenyl]methanols
Authors: Durán‐Galván María , Connell Brian T.
Published: March 2010

[1‐(Silylmethyl)allenyl]methanols 2 were efficiently synthesized from aldehydes and (4‐bromobut‐2‐ynyl)trimethylsilane in the presence of a catalytic amount of CrCl2 and tridentate carbazole ligands. The desired compounds were obtained with good yields (43–88 %) and enantioselectivities (55–78 % ee). Alcohols 2 may be treated with TBAF or 2 M HCl in the case of aliphatic substrates, to provide (1,3‐butadien‐2‐yl)methanols 3 in 43–81 % yields. This method allows the synthesis of dienes 3 with no regioselectivity problems, and it tolerates a large number of functionalities.
Particle trapping using dielectrophoretically patterned carbon nanotubes
Authors: Khoshmanesh Khashayar , Zhang Chen , Nahavandi Saeid , Tovar‐Lopez Francisco J. , Baratchi Sara , Hu Zheng , Mitchell Arnan , Kalantar‐zadeh Kourosh
Published: March 2010

This study presents the dielectrophoretic (DEP) assembly of multi‐walled carbon nanotubes (MWCNTs) between curved microelectrodes for the purpose of trapping polystyrene microparticles within a microfluidic system. Under normal conditions, polystyrene particles exhibit negative DEP behaviour and are repelled from microelectrodes. Interestingly, the addition of MWCNTs to the system alters this situation in two ways: first, they coat the surface of particles and change their dielectric properties to exhibit positive DEP behaviour; second, the assembled MWCNTs are highly conductive and after the deposition serve as extensions to the microelectrodes. They establish an array of nanoelectrodes that initiates from the edge of microelectrodes and grow along the electric field lines. These nanoelectrodes can effectively trap the MWCNT‐coated particles, since they cover a large portion of the microchannel bottom surface and also create a much stronger electric field than the primary microelectrodes as confirmed by our numerical simulations. We will show that the presence of MWCNT significantly changes performance of the system, which is investigated by trapping sample polystyrene particles with plain, COOH and goat anti‐mouse IgG surfaces.
Measurements of acid volatile sulfide and simultaneously extracted metals are irreproducible among laboratories
Authors: Hammerschmidt Chad R. , Burton G. Allen
Published: March 2010

Partitioning with solid phases is a principal control on availability and associated toxicity of metals to aquatic biota. In anoxic sediments, environmentally active fractions of sulfide and associated metals are defined operationally as acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM). Ratios of these chemical parameters are often used in establishing equilibrium partitioning sediment benchmarks for toxicity and, therefore, require analytical accuracy to be useful. To investigate the reproducibility and accuracy of AVS and SEM measurements, we distributed subsamples of four physicochemically disparate stream sediments to seven independent laboratories, including our own, for analysis of both AVS and SEM (Cd, Cu, Pb, Ni, and Zn). Synthesis of these results shows that AVS varied from 70 to 3,500× and SEM ranged from 17 to 60× among laboratories for each of the four sediments. Inadequate detection limits for AVS precluded calculation of SEM:AVS ratios for two of the deposits, whereas the ratio varied more than 50-fold among laboratories for the other two sediments. This work highlights the need for improved quality control and standardization of methods for determination of AVS and SEM in sediments, and suggests that predictions of metal toxicity in sediments can be laboratory specific, which raises concerns on the use of the AVS:SEM model for risk assessments and regulatory decisions. Environ. Toxicol. Chem. 2010;29:1453–1456. © 2010 SETAC
Relating the ability of mallards to ingest high levels of sediment to potential contaminant exposure in waterfowl
Authors: Heinz Gary H. , Beyer W. Nelson , Hoffman David J. , Audet Daniel J.
Published: March 2010

When waterfowl feed from the bottom of bodies of water, they sometimes ingest sediments along with their food, and this sediment can be a major source of contaminants. Learning how much sediment waterfowl can consume in their diet and still maintain their health would be helpful in assessing potential threats from contaminants in sediment. In a controlled laboratory study the maximum tolerated percentage of sediment in the diet of mallards (Anas platyrhynchos) was measured. When fed a well-balanced commercial avian diet, 50, 60, or 70% sediment in the diet on a dry-weight basis did not cause weight loss over a two-week period. Ducks fed this same commercial diet, but containing 80 or 90% sediment, lost 8.6 and 15.6% of their body weight, respectively, in the first week on those diets. After factoring in the ability of the mallards to sieve out some of the sediment from their diet before swallowing it, we concluded that the mallards could maintain their health even when approximately half of what they swallowed, on a dry-weight basis, was sediment. Environ. Toxicol. Chem. 2010;29:1621–1624. © 2010 SETAC
Dioxin transfer from sediment to the infaunal surface deposit-feeding polychaetePerinereis nuntiain a laboratory-rearing experiment
Authors: Kono Kumiko , Tanaka Hiroyuki , Koyama Jiro
Published: March 2010

In the presented study a laboratory experiment was conducted to investigate the transfer of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) from environmentally contaminated marine sediment to an infaunal surface deposit-feeding polychaete, Perinereis nuntia. Polychaetes were exposed to contaminated sediment for 42 d, and elimination of these compounds was studied for an additional 28 d. The sediment uptake rate coefficients (ks), elimination rate constants (k2), and the biota-sediment accumulation factors (BSAFs) were determined for PCDDs, PCDFs (PCDD/Fs), and dioxin-like PCBs. Each of these compounds was transferred from sediment to polychaete except for hepta- and octachlorinated PCDD/Fs. The BSAFs for dioxin-like PCBs (0.13–2.2) were significantly higher than those for PCDD/Fs (0.00022–0.36). The BSAF, ks, and k2 values obtained in the present study indicate that the bioaccumulation characteristics of PCDD/Fs in polychaete are similar to those in fish, and depend on their physical and chemical properties such as hydrophobicity and size of molecules. The ks values for PCDD/Fs and dioxin-like PCBs declined with an increase in their log KOW values, indicating a decrease in bioavailability. The negative exponential relationships of k2 versus KOW were observed for these compounds. The slope for the log-normalized regression of k2 versus KOW for the PCDD/Fs was smaller than that for the dioxin-like PCBs and that of ks versus KOW for the PCDD/Fs. Therefore, the negative exponential relationship of BSAF versus KOW was observed for PCDD/Fs, but not for dioxin-like PCBs. Environ. Toxicol. Chem. 2010;29:1512–1519. © 2010 SETAC
Stress response of heavy metal mixture present in wastewater and leachate on heat-shock protein 47-transfected cells
Authors: Fredj Fahmi Ben , Irie Mitsuteru , Han Junkyu , Yamada Parida , Limam Atef , Ghrabi Ahmed , Morio Takahiro , Isoda Hiroko
Published: March 2010

Heavy metals present in water environment and hazardous sites as single compounds or mixture may drastically affect human health. In the present work, we investigated the risk assessment of wastewater effluents and leachate with a focus on three heavy metals—nickel (Ni), cadmium (Cd), and lead (Pb)—and their combined effect on mammalian cells, using Chinese hamster ovary cells transfected with the heat-shock protein (HSP) 47 promoter. The heavy metal mixture model was designed based on the concentrations of metals in wastewater effluents and leachate sampled in Tunisia. Using a ternary diagram, we investigated the stress response of the interaction model. This research indicated that the single heavy metals induced the stress response on HSP(+) cells even at concentrations lower than the local and international guidelines. Differences in water quality likely influenced the metal responses such that the organic composition of the leachate increased the stress response induced by the heavy metals exclusively, whereas the effluents included organic compounds that were able to mask the heavy metal effect. The mixture characterization discovered the key role played by the high levels of Ni or combination of Cd and Pb to induce the highest stress response following 3-h incubation. Heat-shock protein 47 has proven its effectiveness for assessing the heavy metal mixture effect even at low concentrations. Furthermore, the combination of a bioassay system with a statistical model proved extremely useful for better understanding the major contributors to the stress response of the mixture. Environ. Toxicol. Chem. 2010;29:1637–1647. © 2010 SETAC
Microbial transformation of isopinocampheol and caryophyllene oxide
Authors: Noma Yoshiaki , Hashimoto Toshihiro , Uehara Shinya , Asakawa Yoshinori
Published: March 2010

The biotransformation of (+)‐isopinocampheol and (−)‐isopinocampheol and (6R)‐(−)‐caryophyllene oxide was carried out by Aspergillus niger TBUYN‐2. A. niger converted (+)‐isopinocampheol to give (+)‐5‐hydroxyisopinocampheol and (+)‐1‐hydroxyisopinocampheol. On the other hand, (−)‐isopinocampheol was converted to (−)‐5‐hydroxyisopinocampheol, (−)‐1‐hydroxyisopinocampheol and (+)‐2‐hydroxyisopinocampheol. In the case of (6R)‐(−)‐caryophyllene oxide, (−)‐caryophyllene‐12‐oic acid and (−)‐caryophyllene‐6,7,12‐triol were obtained as new compounds. Clovandiol, which is a component of Salvia canariensis, was also obtained from (6R)‐(−)‐caryophyllene oxide following incubation for 4 days with shaking in medium without microorganisms. Copyright © 2010 John Wiley & Sons, Ltd.
Non‐Newtonian blood flow study in a model cavopulmonary vascular system
Authors: Chitra K. , Sundararajan T. , Vengadesan S. , Nithiarasu P.
Published: March 2010

A transient haemodynamic study in a model cavopulmonary vascular system has been carried out for a typical range of parameters using a finite element‐based Navier–Stokes solver. The focus of this study is to investigate the influence of non‐Newtonian behaviour of the blood on the haemodynamic quantities, such as wall shear stress (WSS) and flow pattern. The computational fluid dynamics (CFD) model is based on an artificial compressibility characteristic‐based split (AC‐CBS) scheme, which has been adopted to solve the Navier–Stokes equations in space–time domain. A power law model has been implemented to characterize the shear thinning nature of the blood depending on the local strain rate. Using the computational model, numerical investigations have been performed for Newtonian and non‐Newtonian flows for different frequencies and input pulse forms. The haemodynamic quantities observed in total cavopulmonary connection (TCPC) for the above conditions suggest that there are considerable differences in average (about 25–40%) and peak (about 50%) WSS distributions, when the non‐Newtonian behaviour of the blood is taken into account. The lower WSS levels observed for non‐Newtonian cases point to the higher risk of lesion formation, especially at higher pulsation frequencies. A realistic pulse form is relatively safer than a sinusoidal pulse as it has more energy distributed in the higher harmonics, which results in higher average WSS values. The present study highlights the importance of including non‐Newtonian shear thinning behaviour for modelling blood flow in the vicinity of repaired arterial connections. Copyright © 2010 John Wiley & Sons, Ltd.
Simulation of gravity currents using the thermal lattice Boltzmann method
Authors: Lizhong Yang , Junqi Ye , Yafei Wang
Published: March 2010

The lattice Boltzmann method (LBM) is becoming an effective numerical technique of computational fluid dynamics (CFD). In this study, with some new thermal LBM schemes being proposed, the LBM is used to simulate the gravity current prior to backdraft (a particular and hazardous phenomenon in compartment fire) within laminar restrictions. The dimensionless time for gravity current traveling from the opening to the rear wall of a bench‐scale compartment is calculated under different opening geometries, respectively, including: full end opening, upside‐slot end opening, middle‐slot end opening, downside‐slot end opening, and slot ceiling opening. The application is very successful and the results show that the dimensionless time under the slot ceiling opening is the longest. Among the slot end openings, similar dimensionless time has been obtained for the upside‐slot and middle‐slot end openings, which is shorter than the downside‐slot end opening. For the full end opening, the shortest dimensionless time is obtained. Finally, some valuable advices are given for fire protection engineering. Copyright © 2010 John Wiley & Sons, Ltd.
Application of a locally conservative Galerkin (LCG) method for modelling blood flow through a patient‐specific carotid bifurcation
Authors: Bevan R. L. T. , Nithiarasu P. , Van Loon R. , Sazonov I. , Luckraz H. , Garnham A.
Published: March 2010

In the present work, blood flow through a patient‐specific carotid bifurcation is thoroughly analysed. A locally conservative Galerkin spatial discretization is applied along with an artificial compressibility and characteristic‐based split scheme to solve the 3D incompressible Navier–Stokes equations. Boundary layer meshes are introduced to accurately resolve high near‐wall velocity gradients inside a patient‐specific carotid bifurcation. A total of six haemodynamic wall parameters have been brought together to analyse the regions of possible atherogenesis within the domain. The results show that wall shear stress (WSS) is high (6–15 Pa) near the apex, along with a small region where WSS exceeded 20 Pa. This peak WSS region is close to the inner wall of the external carotid artery (ECA). It is also clear from the results that low WSS occurred in the common carotid artery (CCA). High oscillatory shear occurred in the CCA distal to a local narrowing of the internal carotid artery and along the outer wall, indicating a potential region of atherogenesis. The highest values of wall shear stress angle deviation and wall shear stress angle gradient occur at the apex. The wall shear stress temporal gradient reached 4000 Pa/s near the apex, closer to the ECA. Wall shear stress spatial gradient distribution corresponded with the WSS distribution, with a maximum occurring at the apex. Copyright © 2010 John Wiley & Sons, Ltd.
Effect of Creep of Ferritic Interconnect on Long‐Term Performance of Solid Oxide Fuel Cell Stacks
Authors: Liu W. N. , Sun X. , Khaleel M. A.
Published: March 2010

High‐temperature ferritic alloys are potential candidates as interconnect (IC) materials and spacers due to their low cost and coefficient of thermal expansion (CTE) compatibility with other components for most of the solid oxide fuel cells (SOFCs). However, creep deformation becomes relevant for a material when the operating temperature exceeds or even is less than half of its melting temperature (in degrees of Kelvin). The operating temperatures for most of the SOFCs under development are around 1,073 K. With around 1,800 K of the melting temperature for most stainless steel (SS), possible creep deformation of ferritic IC under the typical cell operating temperature should not be neglected. In this paper, the effects of IC creep behaviour on stack geometry change and the stress redistribution of different cell components are predicted and summarised. The goal of the study is to investigate the performance of the fuel cell stack by obtaining the changes in fuel‐ and air‐channel geometry due to creep of the ferritic SS IC, therefore indicating possible changes in SOFC performance under long‐term operations. The ferritic IC creep model was incorporated into software SOFC‐MP and Mentat‐FC, and finite element analyses (FEAs) were performed to quantify the deformed configuration of the SOFC stack under the long‐term steady‐state operating temperature. It was found that the creep behaviour of the ferritic SS IC contributes to narrowing of both the fuel‐ and the air‐flow channels. In addition, stress re‐distribution of the cell components suggests the need for a compliant sealing material that also relaxes at operating temperature.
The Ionic Conductivity of a Nafion® 1100 Series of Proton‐exchange Membranes Re‐cast from Butan‐1‐ol and Propan‐2‐ol
Authors: Slade S. M. , Ralph T. R. , Ponce de León C. , Campbell S. A. , Walsh F. C.
Published: March 2010

The ionic conductivity of Nafion® 1100 extruded membranes re‐cast from solutions of butan‐1‐ol and propan‐2‐ol is measured in 0.5 mol dm–3 H2SO4 at 295 K, using an immersed, four‐electrode d.c. technique. The general trend is an increasing conductivity for the thicker membranes. Materials which were solution‐cast from butan‐1‐ol yielded the highest conductivity while a series of membranes with lower conductivities (similar to those of an extruded Nafion® 1100 series of membranes) was found using propan‐2‐ol. The conductivity results indicate that membranes manufactured by extrusion and casting from various solvents might have different structures. Differences in the water content and conductivity of the membranes are considered to arise from the impact of processing conditions on the surface and bulk structure of the membranes.
Preparation of Bimodal Porous Carbon Supported PtRu Catalysts for Fuel Cells
Authors: Hwang S. , Park G.‐G. , Yim S.‐D. , Park S.‐H. , Yang T.‐H. , Kim H. , Kim C.‐S.
Published: March 2010

In this work, we synthesised the bimodal porous carbon supported electro‐catalyst as a novel catalyst for fuel cells. For this purpose, the bimodal porous carbons with different pore sizes were prepared by imprinting method. Three kinds of bimodal porous carbons were fabricated by using the silica spheres with diameters of ca. 50, 100 and 300 nm and SBA‐15 particle having 200–250 nm diameter and 700–900 nm length as templates. The BET surface areas of the bimoal porous carbons were determined to be 235–294 m2 g–1, which are similar to that of Vulcan XC72. To evaluate the electro‐catalytic activity, the PtRu nanoparticles of ca. 1.9–2.6 nm were loaded on the bimodal porous carbon supports. The PtRu/C100, synthesised by using SBA‐15 and 100 nm silica sphere, had the higher electrochemical surface area (ECSA) and the lower on‐set potential and showed comparable performance with the commercial catalyst.
Iron and Copper Containing Oxygen Reduction Catalysts From Templated Glucose–Histidine
Authors: Galbiati I. , Bianchi C. L. , Longhi M. , Carrà A. , Formaro L.
Published: March 2010

Nitrogen doped carbons loaded with non‐precious transition metals are currently investigated as substitutes of Pt‐based catalysts for oxygen reduction in polymer electrolyte fuel cells (PEMFCs). This paper reports the preparation of one kind of such catalysts using glucose/histidine mixtures added with Fe and Cu salts in the presence of silica gels as hard templating agent to increase carbon surface area. The resulting carbons contain nitrogen in amounts that depend on heating temperature (T = 600 and 900 °C) on the glucose/histidine molar ratio and, more weakly, on the relative Fe/Cu amount. Surface areas are a function of reactant concentration and heating temperature, whereas pore size and pore size distribution only depend on glucose/histidine molar ratio. Cyclic voltammetry results on oxygen reduction depend on Fe/Cu ratio, the best result both in terms of incipient oxygen reduction potentials and currents being observed on samples only containing Fe, with no Cu added.
Phase and Microstructural Stability of Electrolyte Matrix Materials for Molten Carbonate Fuel Cells
Authors: Choi H.‐J. , Lee J.‐J. , Hyun S.‐H. , Lim H.‐C.
Published: March 2010

LiAlO2 powder is used as a material for molten‐carbonate fuel cell (MCFC) matrices. The physical and chemical stabilities of LiAlO2 powder during MCFC operation determine the performance and lifetimes of the cells. Change to the phase and particle size in the allotropic phase of LiAlO2 was examined with long‐term stability tests on pure α‐LiAlO2 matrix, Al‐reinforced α‐LiAlO2 matrix, Al‐reinforced γ‐LiAlO2 matrix, aqueous γ‐LiAlO2 matrix and an α‐/β‐LiAlO2 mixture powder in molten carbonate at 650 °C in air. In the γ‐LiAlO2 and α‐/β‐LiAlO2 mixture, the particle growth was continuous from the early stages of heat‐treatment to 20,000 h. Crystalline phase transformation (γ‐LiAlO2 and β‐LiAlO2 to α‐LiAlO2 and γ‐LiAlO2, respectively) of these powders and matrices also occurred, and γ‐LiAlO2 made the third phase like LiAl5O8. By contrast, the sizes of these particles and the crystalline phase of α‐LiAlO2 did not change during immersion tests. These results show that, among α‐/β‐ and γ‐LiAlO2, α‐LiAlO2 is the most stable phase in molten carbonate.
A non‐functioning vitamin D receptor predisposes to leukaemoid reactions in mice
Authors: Erben Reinhold G. , Zeitz Ute , Weber Karin , Stierstorfer Birgit , Wolf Georg , Schmahl Wolfgang , Balling Rudi , Quintanilla‐Martinez Leticia
Published: March 2010

The vitamin D hormone 1,25‐dihydroxyvitamin D3 [1,25(OH)2D3], the biologically active form of vitamin D, is not only essential for mineral metabolism but may have important functions beyond calcium homoeostasis. By gene targeting, we have recently generated mice expressing a functionally inactive mutant vitamin D receptor (VDR). After a change in environmental conditions from specific pathogen free (SPF) conditions to a modified barrier system, a high percentage of aged mutant, but not wild‐type, mice developed a haematological disorder characterized by splenomegaly, granulocytosis, thrombocytosis and dysplastic changes with displacement of erythropoiesis in bone marrow during the following months. All cases were associated with very high serum levels of the acute phase reaction protein serum amyloid A (SAA). Serological testing of affected mice revealed antibodies against murine hepatitis virus (MHV). However, electron microscopy of spleen and bone marrow cells did not reveal virus particles, and clinical signs of infectious diseases were absent. We hypothesize that a non‐functioning VDR is associated with a latent defect in the regulation of myeloid cell differentiation and proliferation. Under the conditions of environmental stress, this latent defect may predispose to a deregulation of myelopoiesis in the form of a leukaemoid reaction accompanied by dysplastic changes. Thus, 1,25(OH)2D3 may be an important inhibitory factor in the onset and progression of myeloproliferative and myelodysplastic diseases. Copyright © 2010 John Wiley & Sons, Ltd.
Determination of antituberculosis drug concentration in human plasma by MALDI‐TOF/TOF
Authors: Notari Stefania , Mancone Carmine , Sergi Manuel , Gullotta Francesca , Bevilacqua Nazzario , Tempestilli Massimo , Urso Rocco , Lauria Francesco Nicola , Pucillo Leopoldo Paolo , Tripodi Marco , Ascenzi Paolo
Published: March 2010

Therapeutic drug monitoring allows to determine the best dosage regimen adapted to each patient optimizing the therapeutic benefits, while minimizing the risk for side effects. Here, the first methodological approach based on matrix‐assisted laser desorption/ionization source equipped with tandem time‐of‐flight (MALDI‐TOF/TOF) mass spectrometry for the determination of the antituberculosis (anti‐TB) drugs ethambutol, pyrazinamide, rifampicin, and streptomycin concentration in the plasma of tuberculosis‐infected patients is reported. The volume of the plasma sample was 200 μL. Plasma samples were cleaned‐up by protein precipitation and evaporated in a water bath under a nitrogen stream. The extracted samples were reconstituted with 200 μL of 50% methanol‐0.03% formic acid solution (v/v), spiked with known amounts of anti‐TB drugs, mixed (1:1) with a saturated matrix solution (4‐hydroxybenzoic acid in 50% acetonitrile‐0.1% trifluoracetic acid solution; v/v), and spotted onto the MALDI‐TOF/TOF sample target plate. The anti‐TB drug concentration was determined by standard additions analysis. Regression of standard additions was linear over the whole anti‐TB drug concentration range explored (the final anti‐TB drug concentration ranged from 0.20 to 200 pmol/μL). The absolute recovery of the anti‐TB drugs ranged between 87 and 110%. The minimal ethambutol, pyrazinamide, rifampicin, and streptomycin concentration detectable by MALDI‐TOF/TOF is 0.08, 0.20, 0.12, and 0.15 pmol/μL, respectively. © 2010 IUBMB IUBMB Life, 62(5): 387–393, 2010