bluuebunny/crossref_metadata_2025 huggingface dataset:
Expression of Orexin A and its Receptor 1 in the Bovine Urethroprostatic Complex
Authors: Russo Finizia , Pavone Luigi Michele , Tafuri Simona , Avallone Luigi , Staiano Norma , Vittoria Alfredo
Published: January 2008

Orexin A (oxA) and orexin B are recently discovered peptides derived from the proteolytic cleavage of the common precursor prepro‐orexin. They bind two G protein‐coupled receptors, defined orexin 1 (ox1R) and orexin 2 receptor. Both peptides are highly expressed in the lateral hypothalamic area of the brain and are involved in the regulation of many functions of the body, the best investigated of which is food intake. Recent data described the presence of orexins in peripheral organs such as the adrenal glands, stomach, bowel, pancreas, and testis. Here, we report the detection of oxA and ox1R in the exocrine and endocrine cytotypes of the cattle urethroprostatic complex by using immunohistochemistry. The expression of prepro‐orexin and ox1R mRNA transcripts in the prostatic tissue was assessed by reverse‐transcriptase polymerase chain reaction, while the presence of both the proteins in the tissue was confirmed by Western blotting analysis. Our findings provide the first evidence for the presence of oxA and ox1R in the urethroprostatic complex of the cattle and demonstrate that both proteins are locally synthesized, thus suggesting a role for oxA on both physiological and pathological functioning of the complex. Anat Rec, 291:169–174, 2008. © 2008 Wiley‐Liss, Inc.
Multifunctional biomass production systems –an overview with presentation of specific applications in India and Sweden
Authors: Berndes Göran , Börjesson Pål , Ostwald Madelene , Palm Matilda
Published: January 2008

This perspective discusses multi‐functional biomass production systems, which are located, designed, integrated and managed so as to provide specific environmental services, in addition to biomass supply. Besides discussing the general concept and outlining a range of different possible applications, we present in somewhat more detail specific applications of such systems for the cases of Sweden and India. The overall conclusion is that the environmental benefits from a large‐scale establishment of multi‐functional biomass production systems could be substantial. Given that suitable mechanisms to put a premium on the provided environmental services can be identified and implemented, additional revenues can be linked to biomass production systems and this could enhance the socioeconomic attractiveness and significantly improve the competitiveness of the produced biomass on the market. The provision of additional environmental services also contributes to local sustainable development, which is in many cases a prerequisite for local support for the production systems. © 2008 Society of Chemical Industry and John Wiley & Sons, Ltd
Azulene‐Moiety‐Based Ligand for the Efficient Sensitization of Four Near‐Infrared Luminescent Lanthanide Cations: Nd3+, Er3+, Tm3+, and Yb3+
Authors: Zhang Jian , Petoud Stéphane
Published: January 2008

The ML4 complexes formed by reaction between the bidentate azulene‐based ligand diethyl 2‐hydroxyazulene‐1,3‐dicarboxylate (HAz) and several lanthanide cations (Pr3+, Nd3+, Gd3+, Ho3+, Er3+, Tm3+, Yb3+, and Lu3+) have been synthesized and characterized by elemental analysis, FT‐IR vibrational spectroscopy and electrospray ionization mass spectroscopy. Spectrophotometric titrations have revealed that four Az− ligands react with one lanthanide cation to form the ML4 complex in solution. Studies of the luminescence properties of these ML4 complexes demonstrated that Az− is an efficient sensitizer for four different near‐infrared emitting lanthanide cations (Nd3+, Er3+, Tm3+, and Yb3+); the resulting complexes have high quantum yield values in CH3CN. The near‐infrared emission arising from Tm3+ is especially interesting for biologic imaging and bioanalytical applications since biological systems have minimal interaction with photons at this wavelength. Hydration numbers, representing the number of water molecules bound to the lanthanide cations, were obtained through luminescence lifetime measurements and indicated that no molecules of water/solvent are bound to the lanthanide cation in the ML4 complex in solution. The four coordinated ligands protect well the central luminescent lanthanide cation against non‐radiative deactivation from solvent molecules.
Concise Enantioselective Total Syntheses of (+)‐Homochelidonine, (+)‐Chelamidine, (+)‐Chelidonine, (+)‐Chelamine and (+)‐Norchelidonine by a PdII‐Catalyzed Ring‐Opening Strategy
Authors: Fleming Matthew J. , McManus Helen A. , Rudolph Alena , Chan Walter H. , Ruiz Jérémy , Dockendorff Chris , Lautens Mark
Published: January 2008

New enantioselective syntheses of the B/C hexahydrobenzo[c]phenanthridine alkaloids (+)‐homochelidonine, (+)‐chelamidine, (+)‐chelidonine, (+)‐chelamine, and (+)‐norchelidonine are described. Our rapid and convergent route to this class of natural products involved the development and application of a PdII‐catalyzed asymmetric ring‐opening reaction of a meso‐azabicyclic alkene with an aryl boronic acid as the key step. By screening a variety of functionalized ortho‐substituted aryl boronic acids, chiral ligands and reaction conditions we were able to prepare the requisite cis‐1‐amino‐2‐aryldihydronaphthalenes in high yield and in up to 90 % ee. Early attempts to complete the synthesis of (+)‐homochelidonine using an N‐Boc azabicyclic alkene are described in full. The successful route required a protecting group alteration followed by B ring formation and then stereoselective installation of the C‐11 syn‐hydroxy group by regioselective epoxide ring‐opening using a hydride source. Ring‐opening of the same epoxide intermediate with water ultimately led to the synthesis of (+)‐chelamidine. The same strategy was then used to synthesize the other structurally similar B/C hexahydrobenzo[c]phenanthridine alkaloids, (+)‐chelidonine, (+)‐chelamidine, and (+)‐norchelidonine.
Isotopic difference spectra as an aide in determining absolute configuration using vibrational optical activity: Vibrational circular dichroism of 13C‐ and 2H‐labelled nonamethoxy cyclotriveratrylene
Authors: Freedman Teresa B. , Cao Xiaolin , Luz Zeev , Zimmermann Herbert , Poupko Raphy , Nafie Laurence A.
Published: January 2008

The use of isotopic difference spectra in vibrational optical activity is demonstrated as a supplemental aide in determining the absolute configuration of chiral molecules. It is shown that IR and VCD difference spectra associated with isotopic substitution observed in experimental spectra can be accurately reproduced by density functional theory calculations when the IR and VCD spectra of the original isotopomer are calculated to reasonable accuracy. Results for isotopically substituted nonamethoxy cyclotriveratrylene are presented to illustrate the degree of agreement between measured and calculated IR and VCD difference spectra for several isotopomers of this molecule. These findings highlight the utility of isotoptic substitution as an aide to verifying the determination of absolute configuration using vibrational optical activity. Chirality, 2008. © 2008 Wiley‐Liss, Inc.
Investigations on Surface Modified Dendrimers: Enzymatic Hydrolysis and Uptake into MCF‐7 Breast Cancer Cells
Authors: Kapp Timo , Francke Peter , Gust Ronald
Published: January 2008

A series of G0 and G1 generation 1,3,5‐tris(3‐aminopropyl)benzene dendrimers surface modified with the amino acids phenylalanine (Phe), methionine (Met), aspartic acid (Asp), and diaminopropionic acid (Dap) was investigated with regard to their stability against enzymatic hydrolysis with the model enzymes papain, chymotrypsin, trypsin, and pepsin. Additionally, the cytosol of MCF‐7 cells was used to get an insight into the possible degradation in intracellular medium. The cytosol, chymotrypsin, and papain had similar activities on the tested dendrimers and efficiently cleaved methionine and phenylalanine from the surface of the dendrimers. The cellular uptake of the dendrimers into the MCF‐7 cells depended on the surface modification (Phe>Met unmodified≫Dap=Asp) and the generations (G0>G1).
Competitive Inhibitors of Helicobacter pylori Type II Dehydroquinase: Synthesis, Biological Evaluation, and NMR Studies
Authors: Sánchez‐Sixto Cristina , Prazeres Verónica F. V. , Castedo Luis , Suh Se Won , Lamb Heather , Hawkins Alastair R. , Cañada Francisco Javier , Jiménez‐Barbero Jesús , González‐Bello Concepción
Published: January 2008

Several 3‐heteroaryl analogs of the known dehydroquinase inhibitor (1R,4R,5R)‐1,4,5‐trihydroxy‐2‐cyclohexene‐1‐carboxylic acid (4) were synthesized and tested as inhibitors of Helicobacter pylori type II dehydroquinase, the third enzyme of the shikimic acid pathway. All of these compounds proved to be reversible competitive inhibitiors of this enzyme and proved to be, with the exception of nitrile 8 e, more potent than the parent inhibitor 4 (Ki=370  μM). The 2‐thienyl derivative 8 b was found to be the most potent inhibitor of the series and has a Ki value of 540 nM, which is almost seven hundred times lower than that of the parent inhibitor. The 3‐nitrothienyl derivative 8 d and 2‐furanyl derivative 8 a also had a good affinity of 1 μM. The conformation of the potent competitive inhibitor 8 b, when bound in the active site of the H. pylori enzyme, was elucidated by 1D‐selective inversion NOE, Saturation Transfer Difference (STD) and transferred NOESY NMR experiments. One of the conformations that exists in solution for the potent competitive inhibitor 2‐thienyl derivative 8 b is selected when it is bound to the active site of the enzyme. In the bound conformation derivative 8 b has the sulfur atom of its thienyl group oriented towards the double bond of the cyclohexene moiety. The large STD effects observed for the aromatic protons of 8 b show that it is the thiophene side of the ligand that makes closest contact with enzyme protons. Docking studies using GOLD3.0.1 suggest that the conformation determined by NMR allows strong lipophilic interactions with the enzyme residues Pro9, Asn10, Ile11, Gly78 and Ala 79. Competitive STD experiments carried out with high‐, medium‐ and low‐affinity ligands 8 b, 5 d and 5 f show that they all bind in the same site of Helicobacter pylori dehydroquinase.
Modeling stimulus‐driven attentional selection in dynamic natural scenes
Authors: Lázár Anna , Vidnyánszky Zoltán , Roska Tamás
Published: January 2008

In this paper we have developed a neuromorphic model of bottom‐up (BU) visual attentional selection. The output of a recently developed neuromorphic multi‐channel retina model has represented the input of our model. As a first step, a saliency map has been calculated for each retinal channel which, next, has been integrated into a master saliency map. Model parameters have been optimized based on human eye movement data measured during viewing dynamic natural scenes. We have tested two different strategies for weighting the channel‐specific saliency maps during integration into a master map. In the first case, channel weights have been kept constant throughout the verification measurements, whereas, in the other case, they have been updated on each frame, according to the specific properties of the visual input. Surprisingly, the constant channel weighting strategies have performed better than the continually updated ones.

We have measured the model's accuracy by defining the hit ratio (concurrence) between the first few predicted locations (the most salient locations) and the measured fixation locations. Constant weighting methods have achieved ∼74% hit ratio on four predictions. For a comparison, the accidental chance for this case has been less than 20%. This pure BU approach has performed surprisingly well on dynamic natural input. Some practical applications have already been made with task‐dependent simplifications. Copyright © 2008 John Wiley & Sons, Ltd.
Chronic Hepatitis C Infection Is Associated with Higher Hemoglobin Levels in Hemodialysis Patients, But Hepatitis B Infection Is Not
Authors: Chen Chih‐Bin , Chou Che‐Yi , Tseng Yu‐Hsiang , Huang Chiu‐Ching , Chen Walter , Shih Chuen‐Ming
Published: January 2008

BACKGROUND

Chronic hepatitis is associated with increased hemoglobin level in patients with end‐stage renal disease. The aim of this study was to define the individual and combined influence of chronic hepatitis B and C infections on red blood cell status.

METHODS

A total of 524 chronic hemodialysis patients at 5 hemodialysis centers were retrospectively reviewed for the period from March 1 to June 31, 2005. The results of testing using a third‐generation enzyme‐linked immunosorbent assay showed that 345 patients (65.8%) had neither HBV nor HCV (NBC), 55 patients (10.5%) had HBV, 108 (20.6%) had HCV, and 16 (3.1%) had concurrent HBV and HCV infection (BBC). Differences between the 4 groups of patients in the parameters studied were investigated using a multivariate general linear model with the Sidak post hoc test.

RESULTS

The hemoglobin and hematocrit of patients with HCV were 10.5 ± 1.6 g/dL and 31.6% ± 4.7%, respectively, which were significantly higher than the 9.9 ± 1.4 g/dL and 29.7% ± 4% of NBC patients (p = 0.002 and p = 0.001). The erythropoietin (EPO) dose given to patients with HCV was 39.3 ± 40.3 IU/kg/week, significantly lower than the 58.1 ± 40.6 IU/kg/week for those with NBC. The results of the multivariate linear regression analysis suggested that erythropoietin dose, elevated liver functional test results, and HCV infection were major factors affecting red cell production (p < 0.001, p < 0.02, and p < 0.05, respectively).

CONCLUSION

Hepatitis C virus infection was associated with an increased number of red blood cells, which led to a lowering of the necessary EPO dose, whereas hepatitis B virus infection was not.
Genetic targeting of the endoderm with claudin‐6CreER
Authors: Anderson William J. , Zhou Qiao , Alcalde Victor , Kaneko Osamu F. , Blank Leah J. , Sherwood Richard I. , Guseh J. Sawalla , Rajagopal Jayaraj , Melton Douglas A.
Published: January 2008

A full description of the ontogeny of the β cell would guide efforts to generate β cells from embryonic stem cells (ESCs). The first step requires an understanding of definitive endoderm: the genes and signals responsible for its specification, proliferation, and patterning. This report describes a global marker of definitive endoderm, Claudin‐6 (Cldn6). We report its expression in early development with particular attention to definitive endoderm derivatives. To create a genetic system to drive gene expression throughout the definitive endoderm with both spatial and temporal control, we target the endogenous locus with an inducible Cre recombinase (Cre‐ERT2) cassette. Cldn6 null mice are viable and fertile with no obvious phenotypic abnormalities. We also report a lineage analysis of the fate of Cldn6‐expressing embryonic cells, which is relevant to the development of the pancreas, lung, and liver. Developmental Dynamics 237:504–512, 2008. © 2008 Wiley‐Liss, Inc.
Effect of psychological treatment on attentional bias in eating disorders
Authors: Shafran Roz , Lee Michelle , Cooper Zafra , Palmer Robert L. , Fairburn Christopher G.
Published: January 2008

Objective:

The aims of these studies were (a) to investigate the relationship between attentional bias and eating disorders and (b) examine the impact of psychological treatment on attentional bias.

Method:

The first study compared performance on a pictorial dot probe of 82 female patients with clinical eating disorders and 44 healthy female controls. The second study compared the performance of 31 patients with eating disorder on the same task before and after receiving 20 weeks of standardized cognitive behavior therapy. Twenty‐four patients with eating disorder served as wait‐list controls

Results:

With the exception of neutral shape stimuli, attentional biases for eating, shape, and weight stimuli were greater in the patient sample than the healthy controls. The second study found that attentional biases significantly reduced after active treatment only.

Conclusion:

Attentional biases may be an expression of the eating disorder. The question of whether such biases warrant specific intervention requires further investigation. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2008
Transient decrease in interleukin‐7 availability arrests B lymphopoiesis during pregnancy
Authors: Bosco Nabil , Ceredig Rhodri , Rolink Antonius
Published: January 2008

In mice, B lymphopoiesis is transiently arrested during pregnancy, and this is thought to be due to depletion of a hormone‐sensitive bone marrow precursor. In this study, combining in vitro and in vivo approaches with detailed phenotypic and functional analysis of progenitor cells, we have investigated the effects of pregnancy on mouse B cell development. Recently, we characterized a BM progenitor called early progenitor with lymphoid and myeloid potential (EPLM) which, when cultured under B cell conditions, is the immediate precursor of pre‐B1 cells. Results obtained show that during late pregnancy, B cell development was blocked at the EPLM‐to‐pre‐B1 transition. This block was associated with a lack of IL‐7 due to a down‐regulation of IL‐7 gene transcription. Moreover, we established that exogenously administered IL‐7 could rescue B lymphopoiesis in pregnant mice. We conclude that during pregnancy, rather than directly depleting a hormone‐sensitive B cell precursor, hormones dampen BM B cell development by fine‐tuning IL‐7 availability.
Polyfunctional T cell responses are a hallmark of HIV‐2 infection
Authors: Duvall Melody G. , Precopio Melissa L. , Ambrozak David A. , Jaye Assan , McMichael Andrew J. , Whittle Hilton C. , Roederer Mario , Rowland‐Jones Sarah L. , Koup Richard A.
Published: January 2008

HIV‐2 is distinguished clinically and immunologically from HIV‐1 infection by delayed disease progression and maintenance of HIV‐specific CD4+ T cell help in most infected subjects. Thus, HIV‐2 provides a unique natural human model in which to investigate correlates of immune protection against HIV disease progression. Here, we report a detailed assessment of the HIV‐2‐specific CD4+ and CD8+ T cell response compared to HIV‐1, using polychromatic flow cytometry to assess the quality of the HIV‐specific T cell response by measuring IFN‐γ, IL‐2, TNF‐α, MIP‐1β, and CD107a mobilization (degranulation) simultaneously following Gag peptide stimulation. We find that HIV‐2‐specific CD4+ and CD8+ T cells are more polyfunctional that those specific for HIV‐1 and that polyfunctional HIV‐2‐specific T cells produce more IFN‐γ and TNF‐α on a per‐cell basis than monofunctional T cells. Polyfunctional HIV‐2‐specific CD4+ T cells were generally more differentiated and expressed CD57, while there was no association between function and phenotype in the CD8+ T cell fraction. Polyfunctional HIV‐specific T cell responses are a hallmark of non‐progressive HIV‐2 infection and may be related to good clinical outcome in this setting.
Mycobacterium bovis BCG‐infected neutrophils and dendritic cells cooperate to induce specific T cell responses in humans and mice
Authors: Morel Céline , Badell Edgar , Abadie Valérie , Robledo Macarena , Setterblad Niclas , Gluckman Jean Claude , Gicquel Brigitte , Boudaly Sarah , Winter Nathalie
Published: January 2008

Neutrophils are increasingly thought to modulate dendritic cell (DC) functions. We investigated the role of the neutrophil‐DC partnership in the response to Mycobacterium bovis BCG–the vaccine used against tuberculosis. We compared neutrophil‐DC crosstalk in humans and mice, searching for functional differences. In both species, neutrophils captured fluorescent BCG‐enhanced green fluorescent protein (EGFP) and were more phagocytic than DC. Non‐apoptotic BCG‐infected neutrophils clustered with immature DC, establishing intimate contacts with dendrites, at which fluorescent intact bacilli were observed. Physical interactions between neutrophils and DC were required for DC activation. Human BCG‐infected DC produced interleukin (IL)‐10, an inhibitory cytokine, whereas DC exposed to BCG‐infected neutrophils produced low to undetectable amounts of the cytokine. Mouse BCG‐infected neutrophils induced sustained IL‐2 production by DC. Human DC exposed to BCG‐infected neutrophils stimulated recall T cell reactivity from vaccinated donors. Mouse DC infected with recombinant ovalbumin (OVA)‐producing BCG (rBCGova) elicited proliferation of TCR‐OVA‐transgenic CD4 and CD8 T cells. Moreover, exposing DC to rBCGova‐infected neutrophils enhanced OVA presentation. Thus, in mice and humans, neutrophils help DC to cross‐present BCG antigens to T cells. Our results suggest that this “ménage à trois” involving neutrophils, DC and T cells plays a major role in the immune response to BCG.
Photoinduced Ligand Transformation in a Ruthenium Polypyridophenazine Complex
Authors: Rau Sven , Schwalbe Matthias , Losse Sebastian , Görls Helmar , McAlister Cale , MacDonnell Frederick M. , Vos Johannes G.
Published: January 2008

Irradiation of a ruthenium polypyridyl complex in the presence of oxygen leads to the oxidation of a benzodipyridophenazine ligand to a quinone. The corresponding tetraazatetrapyridopentacene complex is not oxidized under the same conditions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
A Tunable Coordination Response of the Phosphorus‐Based Hexadentate Ligand (S)P[N(Me)N=CHC6H4‐o‐OH]3 (LH3): Synthesis and Structure of LM (M = Sc, Cr, Mn, Fe, Co, Ga)
Authors: Chandrasekhar Vadapalli , Azhakar Ramachandran , Pandian Balasubramanian Murugesa , Bickley Jamie F. , Steiner Alexander
Published: January 2008

The multidentate ligand (S)P[N(Me)N=CHC6H4‐o‐OH]3 (LH3) reacts with a number of MIII salts to afford the neutral mononuclear complexes LM (M = Sc, Cr, Mn, Fe, Co and Ga). The coordination behaviour of the ligand is hexadentate in all of these complexes, where it encapsulates the metal ion in a facial 3N,3O coordination mode. All the metal complexes have been characterised by spectroscopic and X‐ray crystallographic methods. The metal atoms in the complexes LSc, LMn, LFe and LGa adopt a distorted octahedral geometry, whereas the geometries of LCr and LCo are more ideal. The electrochemical behaviour of LMn shows that it can be reversibly reduced (E1/2 = –0.13 V) in a single electron process. The achiral ligand LH3 induces chirality in the metal complexes LM upon coordination with the metal ion. All the complexes crystallise as racemic compounds where both the clockwise (Δ) and anticlockwise (Λ) enantiomorphs are present in the crystal structure in an ordered arrangement. Furthermore, all complexes show supramolecular chiral recognition in their crystal structures; the Δ form recognizes the Λ form by means of intermolecular C–H···O and C–H···S interactions.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
[Ta3O3]A (A = Li, Na, K) and [Ta3O3]B[Ta3O3] (B = Ca, Sr, Ba): Sandwich‐Type Complexes Containing Ta3O3– δ and π Double Aromatic Ligands
Authors: Li Si‐Dian , Miao Chang‐Qing , Guo Jin‐Chang
Published: January 2008

A density functional theory investigation on half‐sandwich‐type C3v [Ta3O3]A (A = Li, Na, K) and full‐sandwich‐type D3h [Ta3O3]B[Ta3O3] (B = Ca, Sr, Ba) complexes containing Ta3O3– δ and π double aromatic ligands was performed. The Ta3O3– units serve as robust inorganic ligands in both [Ta3O3]A and [Ta3O3]B[Ta3O3] complex series, which are mainly maintained by A+–[Ta3O3]– or [Ta3O3]––B2+–[Ta3O3]– ionic interactions. These novel complexes turn out to be strongly thermodynamically favored in the gas phases and may be targeted in future experiments to open a new area of coordination chemistry by introducing δ and π double aromatic ligands into complex systems. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Synthesis and Conformational Analysis of Tetrahydroisoquinoline‐Fused 1,3,2‐Oxazaphospholidines and 1,2,3‐Oxathiazol­idines
Authors: Schuster Ildikó , Koch Andreas , Heydenreich Matthias , Kleinpeter Erich , Forró Enikő , Lázár László , Sillanpää Reijo , Fülöp Ferenc
Published: January 2008

The cyclizations of tetrahydroisoquinoline 1,2‐amino alcohols with phenylphosphonic dichloride, bis(2‐chloroethyl)phosphoramidic dichloride, thionyl chloride and sulfuryl chloride were utilized to synthesize 1,5,6,10b‐tetrahydro‐1,3,2‐oxazaphospholo[4,3‐a]isoquinolines (2, 3), 1,5,10,10a‐tetrahydro‐1,3,2‐oxazaphospholo[3,4‐b]isoquinolines (8, 9), 1,5,6,10b‐tetrahydro‐1,2,3‐oxathiazolo[4,3‐a]isoquinolines (4–6) anda 1,5,10,10a‐tetrahydro‐1,2,3‐oxathiazolo[3,4‐b]isoquinoline (11), which are the first representatives of these ring systems. NMR spectroscopic analysis revealed the existence of conformational equilibria that are fast on the NMR timescale. Theoretical DFT calculations pointed to the participation of generally two preferred conformers in the conformational equilibria; the positions of the equilibria were indicated by the experimental NMR spectroscopic parameters, and they are in good agreement with the theoretically calculated energy differences of the participating conformers. For two compounds, which could be not isolated (10, 12), both the preferred conformers and the stereochemistry could be concluded from the DFT calculation results. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Facile Synthesis of Large meso‐Pentafluorophenyl‐Substituted Expanded Porphyrins
Authors: Tanaka Yasuo , Shin Ji‐Young , Osuka Atsuhiro
Published: January 2008

Acid‐catalyzed condensation of meso‐pentafluorophenyl dipyrromethane 1 (100 mM) and pentafluorobenzaldehyde 2 (100 mM) at 0 °C gave a series of expanded porphyrins with even number of pyrrolic subunits up to octadecaphyrin(1.1.1.1.1.1.1.1.1.1.1.1.1.1.1.1.1.1) 18 in improved yields, particularly for larger expanded porphyrins. The solid‐state structure of decaphyrin(1.1.1.1.1.1.1.1.1.1) 10 was revealed by X‐ray diffraction analysis to be a crescent‐like conformation. The Soret‐like absorption bands are increasinglyredshifted as the size of the ring increases, but such atrend becomes nearly saturated for hexadecaphyrin(1.1.1.1.1.1.1.1.1.1.1.1.1.1.1.1) 16 and 18, which exhibit bands in the near‐infrared region at 939 and 953 nm, respectively.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Carbon Cavity Microelectrode for Electrical Wiring of Enzyme by Insoluble Electroactive Species in Aqueous Media
Authors: Cosnier Serge , Ionescu Rodica E. , Keddam Michel , Vivier Vincent
Published: January 2008

The carbon cavity microelectrode (CME), exhibiting a volume of 4×10−6 cm3, offers a genuine alternative for immobilizing and connecting enzymes in aqueous electrolytes by powder of insoluble redox materials. In the present work, the electrochemical behavior of two redox species such as ferrocene (Fc) and tetrathiafulvalene (TTF) was investigated with CME to evaluate their potentialities in the electrical wiring of enzymes. For this purpose, powder of two enzymes, glucose oxidase (GOx) and horseradish peroxidase (HRP), was independently mixed with an insoluble redox material and forced to fill the single micro cavity of a carbon electrode covered by an inert insulator. The presence of the electroactive species, as well as the enzyme wiring was investigated by cyclic voltammetry. The amperometric detection of glucose was carried out by potentiostating the TTF/GOx and the Fc/GOx microelectrodes at 0.25 and 0.35 V respectively. The amperometric detection of H2O2 by the TTF/HRP microelectrode was performed at −0.1 V vs. SCE.
Influence of varying electroosmotic flow on the effective diffusion in electric field gradient separations
Authors: Maynes Daniel , Tenny Joseph , Webbd Brent W. , Lee Milton L.
Published: January 2008

Recently the use electric field gradient focusing (EFGF) to enhance focusing of proteins has been proposed and explored to provide significant improvement in separation resolution. The objective of EFGF is to focus proteins of specific electrophoretic mobilities at distinct stationary locations in a column or channel. This can be accomplished in a capillary by allowing the electric potential to vary in the streamwise direction. Because the electric field is varying, so also is the electrokinetic force exerted on the proteins and the electroosmotic velocity of the buffer solution. Due to the varying electric field, the Taylor diffusion characteristics will also vary along the column, causing a degradation of peak widths of some proteins, dependent on their equilibrium positions and local velocity distributions. The focus of this paper is an analysis that allows characterization of the local Taylor diffusion and resulting protein band peak width as a function of the local magnitude of the EOF relative to the average fluid velocity for both cylindrical and rectangular channels. In general the analysis shows that as the ratio of the local electroosmotic velocity to the average velocity deviates from unity, the effective diffusion increases significantly. The effectiveness of EFGF devices over a range of protein diffusivities, capillary diameters, flow velocities, and electric field gradient is discussed.
Simultaneous analysis of basic, acidic and neutral compounds on an endcapped octadecylsilane silica‐based monolith by pressure‐assisted capillary electrochromatography
Authors: Zhang Tong , Khadra Ibrahim , Euerby Melvin R. , Skellern Graham G. , Watson David G. , Tettey Justice N. A.
Published: January 2008

This simultaneous separation of basic, acidic and neutral analytes by pressure‐assisted CEC (pCEC) using a hybrid (tetramethoxysilane and methyltrimethoxysilane) silica‐based monolith, chemically modified with octadecyldimethylchlorosilane followed by endcapping with hexamethyldisilazane is described. The endcapping resulted in near Gaussian peaks for highly basic analytes such as nortriptyline without a significant loss in the EOF. The migration behaviour of analytes on this phase could be rationalised based on hydrophobicity, electrophoretic mobility and ion‐exchange interactions. The high porosity of the monolith allowed manipulation of the linear velocity of mobile phases by the addition of varying amounts of pressure at the inlet to reduce analysis times and overcome the reversed migration of anionic species towards the detection window in cathodic EOF mode. The concomitant programmed application of pressure (2–4 bar) and voltage (27 kV) facilitated the simultaneous separation of four cationic, four neutral and two anionic compounds in 6 min with efficiencies ranging from 41 000 to 94 000, 57 000 to 77 000 and 180 000 to 210 000 theoretical plates/metre, respectively. The % RSD values of migration times and efficiencies in pCEC mode were less than 3.6 and 7.9%, respectively (n = 5).
Transgenic λ medaka as a new model for germ cell mutagenesis
Authors: Winn Richard N. , Majeske Audrey J. , Jagoe Charles H. , Glenn Travis C. , Smith Michael H. , Norris Michelle B.
Published: January 2008

To address the need for improved approaches to study mutations transmitted to progeny from mutagen‐exposed parents, we evaluated λ transgenic medaka, a small fish that carries the cII mutation target gene, as a new model for germ cell mutagenesis. Mutations in the cII gene in progeny derived from ethyl‐nitrosourea (ENU)‐exposed males were readily detected. Frequencies of mutant offspring, proportions of mosaic or whole body mutant offspring, and mutational spectra differed according to germ cell stage exposed to ENU. Postmeiotic germ cells (spermatozoa/late spermatids) generated a higher frequency of mutant offspring (11%) compared to premeiotic germ cells (3.5%). Individuals with cII mutant frequencies (MF) elevated more than threefold above the spontaneous MF (3 × 10−5) in the range of 10−4 to 10−3 were mosaic mutant offspring, whereas those with MFs approaching 1 × 10−2 were whole body mutant offspring. Mosaic mutant offspring comprised the majority of mutant offspring derived from postmeiotic germ cells, and unexpectedly, from spermatogonial stem cells. Mutational spectra comprised of two different mutations, but at identical sites were unusual and characteristic of delayed mutations, in which fixation of a second mutation was delayed following fertilization. Delayed mutations and prevalence of mosaic mutant offspring add to growing evidence that implicates germ cells in mediating processes postfertilization that contribute to genomic instability in progeny. This model provides an efficient and sensitive approach to assess germ cell mutations, expands opportunities to increase understanding of fundamental mechanisms of mutagenesis, and provides a means for improved assessment of potential genetic health risks. Environ. Mol. Mutagen., 2008. © 2008 Wiley‐Liss, Inc.
Modulatory activity of aLactobacillus caseistrain on 1,2‐dimethylhydrazine‐induced genotoxicity in rats
Authors: Villarini Milena , Caldini Giovanna , Moretti Massimo , Trotta Francesca , Pasquini Rossana , Cenci Giovanni
Published: January 2008

The present study was designed to investigate the putative antigenotoxic effects of supplementing the diet of rats treated with the colon carcinogen 1,2‐dimethylhydrazine hydrochloride (DMH) with aLactobacillus caseistrain using an in vivo approach. The antigenotoxic response was evaluated in colon and liver cells using the alkaline comet assay. Since the balance between the bioactivation and detoxification metabolic pathways is crucial for the formation of toxic and genotoxic metabolites, alterations in the level of some xenobiotic metabolizing enzymes (XME) were studied in liver preparations. In the challenge group (L. casei+ DMH), lactobacilli‐supplemented diet, there was a decrease in the extent of DMH‐induced DNA damage, especially in colon cells. Compared with control rats, there was less basal DNA damage in colon cells of rats fed on a lactobacilli‐supplemented diet. These findings are the first to give clear evidence of DNA‐protective effects of lactobacilli against basal DNA damage. Moreover, the chemopreventive effects were accompanied by changes in the activities of several XME. The observed decrease in the concentration of nonenzymatic antioxidants (i.e. GSH) and the reduced activity of enzymatic antioxidants (i.e., GST, GPx, and SOD) in liver could reflect an overall reduction in the level of oxidative stress in rats on a diet supplemented with theL. caseisuspension compared with control rats (basal state). Thus, the concentrations of GSH and the activities of GST, GPx, and SOD could be downregulated by supplementing the diet withL. caseias a response to an improved antioxidant status. Environ. Mol. Mutagen., 2008. © 2008 Wiley‐Liss, Inc.
Dynamic collapse analysis for a reinforced concrete frame sustaining shear and axial failures
Authors: Elwood Kenneth J. , Moehle Jack P.
Published: January 2008

Shaking table test results from a one‐story, two‐bay reinforced concrete frame sustaining shear and axial failures are compared with nonlinear dynamic analyses using models developed for the collapse assessment of older reinforced concrete buildings. The models provided reasonable estimates of the overall frame response and lateral strength degradation; however, the measured drifts were underestimated by the models. Selected model parameters were varied to investigate the sensitivity of the calculated response to changes in the drift at shear failure, rate of shear strength degradation, and drift at axial failure. For the selected ground motion, the drift at shear failure and rate of shear strength degradation did not have a significant impact on the calculated peak drift. By incorporating shear and axial‐load failure models, the analytical model is shown to be capable of predicting the axial‐load failure for a hypothetical frame with three nonductile columns. Improvements are needed in drift demand estimates from nonlinear dynamic analysis if such analyses are to be used in displacement‐based performance assessments. Copyright © 2008 John Wiley & Sons, Ltd.
Beamforming for satellite communications in emergency situations
Authors: Sow Garmy , Besson Olivier , Boucheret Marie‐Laure , Guiraud Cécile
Published: January 2008

We consider a multi‐beam Ka‐band satellite communication system aimed at operating in emergency situations where terrestrial communications systems are no longer effective. In contrast to most systems which use one single beam to cover a large area, we study here the feasibility of a one beam per user concept, where a beamformer is calculated for each user. This should allow to guarantee the maximum antenna gain towards each user.

We assess the performance of the minimum variance distortionless response (MVDR) beamformer and of a beamformer using a training sequence in realistic scenarios including channel, steering vector and synchronisation errors. We show that both beamformers provide a sufficiently high output signal to noise ratio in a DVB–RCS system. Copyright © 2008 John Wiley & Sons, Ltd.
Increasing the power of identifying gene × gene interactions in genome‐wide association studies
Authors: Kooperberg Charles , LeBlanc Michael
Published: January 2008

In this paper we investigate the power to identify gene × gene interactions in genome‐wide association studies. In our analysis we focus on two‐stage analyses: analyses in which we only test for interactions between single nucleotide polymorphisms that show some marginal effect. We give two algorithms to compute significance levels for such an analyses. One involves a Bonferoni correction on the number of interactions that are actually tested, and one is a resampling procedure similar to the one proposed by [Lin (2006) Am. J. Hum. Genet. 78:505–509]. We also give an algorithm to carry out approximate power calculations for studies that plan to use a two‐stage analysis. We find that for most plausible interaction effects a two‐stage analysis can dramatically increase the power to identify interactions compared to a single‐stage analysis based on simulation studies using known genetic models and data from existing genome‐wide association studies. Genet. Epidemiol. 2008. © 2008 Wiley‐Liss, Inc.
Genome‐wide admixture mapping for coronary artery calcification in African Americans: the NHLBI Family Heart Study
Authors: Zhang Qunyuan , Lewis Cora E. , Wagenknecht Lynne E. , Myers Richard H. , Pankow James S. , Hunt Steven C. , North Kari E. , Hixson James E. , Jeffrey Carr J. , Shimmin Lawrence C. , Borecki Ingrid , Province Michael A.
Published: January 2008

Coronary artery calcification (CAC) is an important measure of subclinical coronary atherosclerosis and an independent predictor of coronary heart disease. To identify the genetic loci contributing to CAC, we conducted a genome‐wide scan with 374 microsatellite markers by applying admixture mapping to 618 African American participants in the US National Heart, Lung, and Blood Institute Family Heart Study, in which 868 European American participants from family heart study and 157 Africans genotyped by the Marshfield Medical Genetics Center were used as the two reference founding populations for the African Americans, and a computer program based on a Markov Chain Monte Carlo algorithm, STRUCTURE 2.1, was used to estimate European and African ancestries among African Americans. A permutation test for random repeated sampling regression of CAC score on marker specific African ancestry found 22 markers statistically significant at the 0.05 level and four markers, D10S189 at 10p14, D20S159 at 20q13, D12S1294 at 12q14, and D6S1053 at 6q12, significant at the 0.01 level. D10S189 and D6S1053 were further confirmed at the 0.05 significance level by regression of CAC on allelic copy number, in which individual ancestry was used as a genetic background covariate to control possible stratification in African Americans. On the basis of the results from this and other independent studies, the location of D6S1053 at 80cM on chromosome 6 (6q12) seems to harbor a highly promising quantitative trait loci for atherosclerosis. Genet. Epidemiol. © 2008 Wiley‐Liss, Inc.
Stereoselective synthesis and biological activities of O‐(E)‐1‐{1‐[(6‐chloropyridin‐3‐yl)methyl]‐5‐methyl‐1H‐1,2,3‐triazol‐4‐yl}ethyleneamino‐O‐ethyl‐O‐arylphosphorothioates
Authors: Zhu Xiao‐Fei , Chen Xiao‐Bao , Yan Man , Shi De‐Qing , Ding Ke‐Rong
Published: January 2008

To find novel lead compounds having high insecticidal activity, a series of phosphorothioate derivatives containing 1,2,3‐triazole and pyridine rings were synthesized by the reaction of 1‐{1‐[(6‐chloropyridin‐3‐yl)methyl]‐5‐methyl‐1H‐1,2,3‐triazol‐4‐yl}ethanone oxime with phosphorochloridothioates. Their structures were confirmed by IR, 1H NMR, 31P NMR, mass spectrometry, and elemental analyses. The structure of 6c was determined by single crystal X‐ray diffraction, which is thermodynamically stable E isomer. The results of preliminary bioassay indicate that some title compounds possess insecticidal activity to some extent. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:15–20, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20367
Synthesis and conformational study of P‐heterocyclic androst‐5‐ene derivatives
Authors: Frank Éva , Schäfer Balázs , Mucsi Zoltán , Keglevich György
Published: January 2008

The reactions of (20R)‐3β‐acetoxy‐21‐hydroxymethylpregn‐5‐en‐20‐ol (2) and (20R)‐3β‐acetoxypregn‐5‐ene‐20,21‐diol (11) with phenylphosphonic dichloride 3 and aryl dichlorophosphates 4–6 afforded novel types of P‐heterocyclic androst‐5‐ene derivatives 7–10 and 12 as epimeric pairs. The diastereomers were separated by column chromatography and were characterized by NMR spectroscopy. Estimation of the stereostructures of the corresponding epimers by B3LYP/631G(d) DFT ab initio calculations suggested that the six‐membered hetero ring in compounds 7b and 8a–10a adopts predominantly a chair conformation, with the P‐substituents in their preferred orientation. The cyclic phosphonate moiety in 7a or 8b–10b, however, seems to exist as an equilibrium mixture of chair–distorted‐boat or chair–chair forms. The theoretical calculations indicate that the conformational equilibrium is shifted toward the distorted‐boat conformer for 7a, with a pseudoequatorial P‐phenyl substituent, whereas for 8b–10b the chair conformer with an equatorial P‐phenoxy group predominates. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:7–14, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20372
Microwave‐assisted synthesis of some 1,2,4‐triazol‐5‐one derivatives
Authors: Kahveci Bahittin , Özil Musa , Serdar Mevlüt
Published: January 2008

A series of 3‐alkyl(aryl)‐4‐(p‐hydroxy‐phenyl)‐4,5‐dihydro‐1H‐1,2,4‐triazol‐5‐ones 2 were obtained from the reaction of alkyl (aryl) ester ethoxycarbonyl hydrazones 1 with p‐hydroxy aniline. The reaction of 1 with 1,4‐diamino benzene (1:1) to afford 3‐alkyl(aryl)‐4‐(p‐aminophenyl)‐4,5‐dihydro‐1H‐1,2,4‐triazol‐5‐ones 3. The reaction of 3 with benzaldehyde gave 3‐alkyl(aryl)‐4‐(4′‐benzilidenamino)‐4,5‐dihydro‐1H‐1,2,4‐triazol‐5‐ones 4. All of the above reactions occurred under microwave heating and conventional methods. Their structures were confirmed by 1H NMR, 13C NMR, IR, and elemental analyses. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:38–42, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20381
A facile and convenient synthesis of tetrasubstituted N‐hydroxypyrroles via intramolecular wittig reaction
Authors: Hekmatshoar Rahim , Nouri Roghieh , Beheshtiha S. Yahya Sh.
Published: January 2008

Treatment of triphenylphosphine with dialkyl acetylenedicarboxylate leads to 1:1 adduct and concomitant protonation of late adduct by pentan‐2,3,4‐trione 3‐oxime gave the reactive intermediate, vinyltriphenylphosphonium salts, which undergoes an intramolecular Wittig reaction to produce tetrasubstituted N‐hydroxypyrroles in fairly high yields. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:100–103, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20382
Facile and efficient method for preparation of schiff bases catalyzed by P2O5/SiO2 under free solvent conditions
Authors: Naeimi Hossein , Sharghi Hashem , Salimi Fariba , Rabiei Khadijeh
Published: January 2008

A simple and convenient method for the preparation of Schiff bases is developed. In this method, the Schiff base compounds were prepared from the reaction of carbonyl compounds with primary amines. In this reaction, P2O5/SiO2 have catalyzed the Schiff base formation in dry media under solvent‐free conditions. Advantages of this method are use of an inexpensive and efficient catalyst, high yields of products, short reaction times, and simpli‐city of the reaction and workup. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:43–47, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20383
Phase II study of gefitinib for the treatment of recurrent and metastatic nasopharyngeal carcinoma
Authors: Chua Daniel T. T. , Wei William I. , Wong Maria P. , Sham Jonathan S. T. , Nicholls John , Au Gordon K. H.
Published: January 2008

Background

This single‐center, phase II study assessed the safety/tolerability and initial efficacy of gefitinib in patients with nasopharyngeal carcinoma (NPC) pretreated with platinum‐based chemotherapy.

Methods

Patients with recurrent and metastatic NPC who had treatment failure with at least 2 lines of chemotherapy including platinum were given gefitinib at a fixed dose of 250 mg daily. Treatment was continued until the patient experienced unacceptable side effects or disease progression.

Results

Nineteen patients were enrolled, having had treatment failure with a median of 2 chemotherapy regimens. Treatment was well tolerated, and only grades 1 to 2 adverse events were observed. None of the patients achieved partial or complete response. Median time‐to‐progression was 4 months, and median overall survival was 16 months.

Conclusion

Gefitinib was well tolerated, but the response rate was poor in this heavily pretreated study population, and its use in NPC is not recommended outside the context of clinical trial. © 2008 Wiley Periodicals, Inc. Head Neck, 2008
Towards network and citizen: Collaborative care for drug abusers
Authors: Kihlström Anita , Wikström Ewa
Published: January 2008

In Sweden like in many other countries, inter‐organizational collaboration has been introduced to co‐ordinate the care for clients. Even so, the knowledge of how inter‐organizational collaboration is developed over time is limited today. This study focuses on how the inter‐organizational collaboration was conducted in the care for drug abusers over a period of 5 years. The study sought to answer the following questions: Which effect does inter‐organizational collaboration have on ways‐of‐working among professionals and which effect does inter‐organizational collaboration have on the services provided by the clients?

We argue that inter‐organizational collaboration is developed through three processes. First, the professionals redefine ‘areas of responsibilities’ in the different organizations. Second, the professionals ‘reconstruct their ways of working’ with clients. Third, the professionals ‘organize a networking model with the client as citizen in the centre’. This paper describes how the three processes appeared in the studied inter‐organizational collaboration project ‘SANNA’ (Collaborative Care for drug abusers). Copyright © 2009 John Wiley & Sons, Ltd.