bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: The Bioinorganic Chemistry and Associated Immunology of Chronic Beryllium Disease
Authors: Scott Brian L. , McCleskey T. Mark , Chaudhary Anu , Hong‐Geller Elizabeth , Gnanakaran S.
Published: September 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Role of Enzymes in Biomineralization Processes
Authors: Weiss Ingrid M. , Marin Frederic
Published: September 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Embryonic Stem Cells: The Mouse Source—Vehicle for Mammalian Genetics and Beyond (Nobel Lecture)
Authors: Evans Martin
Published: September 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Critical Issues in Site‐Specific Targeting of Solid Tumors — The Carrier, the Tumor Barriers and the Bioavailable Drug
Authors: Hamad Islam , Moghimi S. Moein
Published: September 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Monitoring Rapid Chemical Communication in the Brain
Authors: Robinson Donita L. , Hermans Andre , Seipel Andrew T. , Wightman R. Mark
Published: September 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Electron Transfer in DNA and in DNA‐Related Biological Processes. Electrochemical Insights
Authors: Boussicault Fabien , Robert Marc
Published: September 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Single‐Molecule Electron Transfer in Electrochemical Environments
Authors: Zhang Jingdong , Kuznetsov Alexander M. , Medvedev Igor G. , Chi Qijin , Albrecht Tim , Jensen Palle S. , Ulstrup Jens
Published: September 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Topological Ring‐Currents in Condensed Benzenoid Hydrocarbons
Authors: Mallion R. B.
Published: September 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Roaming Atoms and Radicals: A New Mechanism in Molecular Dissociation
Authors: Suits Arthur G.
Published: September 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Modeling and reconstruction of diffuse optical tomography using adjoint method
Authors: Wang Z. G. , Sun L. Z. , Fajardo L. L. , Wang G.
Published: September 2008

A new finite‐element algorithm based on adjoint method is developed to solve the inverse problem of frequent‐domain diffusion equation for soft tissues. With the analytical form of gradients, the adjoint method is expanded to complex domains for the reconstruction of optical parameters in diffuse optical tomography accurately and efficiently. Specific numerical simulations are carried out and compared to validate the proposed algorithm. The results demonstrate that the algorithm is stable and robust to reconstruct optical parameters. Copyright © 2008 John Wiley & Sons, Ltd.
Towards a Quantitative Understanding of Protein Hydration and Volumetric Properties
Authors: Mitra Lally , Rouget Jean‐Baptiste , Garcia‐Moreno Bertrand , Royer Catherine A. , Winter Roland
Published: September 2008

Herein, we probe by pressure perturbation calorimetry (PPC) the coefficient of thermal expansion, the volumetric and the hydration properties of variants of a hyperstable variant of staphylococcal nuclease (SNase), Δ+PHS. The temperature‐dependent volumetric properties of the folded and unfolded states of the wild‐type protein are calculated with previously published data. The present PPC results are used to interpret the volume diagram and expansivity at a molecular level. We conclude that the expansivity of the unfolded state is, to a first approximation, temperature independent, while that of the folded state decreases with increasing temperature. Our data suggest that at low temperature the defining contribution to ΔV comes mainly from excluded volume differences and ΔV for unfolding is negative. In contrast, at high temperatures, differential solvation due to the increased exposed surface area of the unfolded state and, in particular, its larger thermal volume linked to the increased conformational dynamics of the unfolded state ensemble takes over and ΔV for unfolding eventually becomes positive.
Cooperativity between the Halogen Bond and the Hydrogen Bond in H3N⋅⋅⋅XY⋅⋅⋅HF Complexes (X, Y=F, Cl, Br)
Authors: Li Qingzhong , Lin Qingquan , Li Wenzuo , Cheng Jianbo , Gong Baoan , Sun Jiazhong
Published: September 2008

Ab initio calculations are used to provide information on H3N⋅⋅⋅XY⋅⋅⋅HF triads (X, Y=F, Cl, Br) each having a halogen bond and a hydrogen bond. The investigated triads include H3N⋅⋅⋅Br2‐HF, H3N⋅⋅⋅Cl2⋅⋅⋅HF, H3N⋅⋅⋅BrCI⋅⋅⋅HF, H3N⋅⋅⋅BrF⋅⋅⋅HF, and H3N⋅⋅⋅ClF⋅⋅⋅HF. To understand the properties of the systems better, the corresponding dyads are also investigated. Molecular geometries, binding energies, and infrared spectra of monomers, dyads, and triads are studied at the MP2 level of theory with the 6‐311++G(d,p) basis set. Because the primary aim of this study is to examine cooperative effects, particular attention is given to parameters such as cooperative energies, many‐body interaction energies, and cooperativity factors. The cooperative energy ranges from −1.45 to −4.64 kcal mol−1, the three‐body interaction energy from −2.17 to −6.71 kcal mol−1, and the cooperativity factor from 1.27 to 4.35. These results indicate significant cooperativity between the halogen and hydrogen bonds in these complexes. This cooperativity is much greater than that between hydrogen bonds. The effect of a halogen bond on a hydrogen bond is more pronounced than that of a hydrogen bond on a halogen bond.
The development of a ‘best practice’ service for women in a medium‐secure psychiatric setting: treatment components and evaluation
Authors: Long Clive G. , Fulton Barbara , Hollin Clive R.
Published: September 2008

The inadequacy of inpatient facilities for women with severe psychiatric and co‐morbid difficulties has been repeatedly documented. The establishment of effective therapeutic programmes for women in medium psychiatric facilities is also in their infancy, and little research has been undertaken. This article describes the development of a ‘best practice’ psychological treatment programme for women with a dual diagnosis. Emphasis is placed on the need to develop further intensive gender‐specific services using an established model for effective therapeutic service development. In addition to a detailed description of the group therapy programme, staff training initiatives, methods for ensuring treatment integrity and a methodology for service evaluation is given. Copyright © 2008 John Wiley & Sons, Ltd.
Patients' perspective on homework assignments in cognitive–behavioural therapy
Authors: Fehm Lydia , Mrose Jana
Published: September 2008

Homework assignments are an indispensable part of cognitive–behavioural therapy. During the past two decades, a growing number of studies have shed light on its characteristics and effects. However, most studies primarily consider the therapists' view, and little is known about the use of supportive strategies to implement homework assignments in psychotherapy and about patients' attitudes towards regular assignments. To fill this gap, we assessed the attitudes towards homework assignments of 80 outpatients. In addition, those who had received a task during the past session (75%) were asked to report characteristics of their task as well as therapists' behaviour strategies during the assignment of the task. One week later, therapists rated the extent of completion of the task. Results showed that the patients generally had a positive attitude towards homework and that they accomplished most of the tasks. With regard to the therapists' behaviour during the assignment of the task, there seems to be room for improvement. Copyright © 2008 John Wiley & Sons, Ltd.
Iron deficiency anemia and affective response in rhesus monkey infants
Authors: Golub Mari S. , Hogrefe Casey E. , Widaman Keith F. , Capitanio John P.
Published: September 2008

Infant iron deficiency anemia (IDA) occurs spontaneously in monkey populations as it does in humans, providing a model for understanding effects on brain and behavior. A set of 34 monkey infants identified as IDA (hemoglobin <11 g/dl) over a 5‐year period at the California National Primate Research Center (CNPRC) was compared to a set of 57 controls (hemoglobin >12 g/dl) matched for age and caging location. The infants had participated in a Biobehavioral Assessment conducted at 3–4 months of age at CNPRC that included measures of behavioral and adrenocortical response to a novel environment. IDA males differed from control males in two factors (“activity,” “emotionality”) derived from observational data taken on the first and second day of the exposure to the novel environment. In the male infants, IDA was associated with less restriction of activity in the novel environment on both days and less emotionality on the second day (p < .05). IDA males also displayed less response to approach by a human (human intruder test) than did control males. IDA females did not differ from controls. Adrenocortical response was not significantly affected. These findings may be relevant to functional deficits in human infants with IDA that influence later behavior. © 2008 Wiley Periodicals, Inc. Dev. Psychobiol 51: 47–59, 2009
Copper Complexes with the Ligand Methyl Bis(3,5‐dimethylpyrazol‐1‐yl)acetate (Mebdmpza), Generated by In Situ Methanolic Esterification of Bis(3,5‐dimethylpyrazol‐1‐yl)acetic Acid
Authors: Kozlevčar Bojan , Pregelj Tina , Pevec Andrej , Kitanovski Nives , Sánchez Costa José , van Albada Gé , Gamez Patrick , Reedijk Jan
Published: September 2008

Two novel complexes, [CuCl2(Mebdmpza)] (1) and [Cu2(μ‐O4C2)Cl2(Mebdmpza)2] (2) [Mebdmpza = methyl bis(3,5‐dimethylpyrazol‐1‐yl)acetate], were synthesized by reaction of CuCl2 with the precursor ligand bis(3,5‐dimethylpyrazol‐1‐yl)acetic acid (Hbdmpza) in methanol. The X‐ray crystal structures of 1 and 2 revealed that the initial Hbdmpza ligand had reacted with methanol during the crystallization process to yield the esterified ligand Mebdmpza. A reverse Mebdmpza to bdmpza reaction is observed by dissolving [CuCl2(Mebdmpza)] (1) in water to yield [Cu(bdmpza)2]·2H2O. After drying, the latter gives water‐free [Cu(bdmpza)2]. The copper ion in the orange mononuclear complex 1 is tetrahedrally coordinated by two nitrogen atoms (from one ligand) and two chloride ions. The light‐green dinuclear complex 2 exhibits a square‐pyramidal geometry, defined by two ligand nitrogen atoms, two oxalato oxygen atoms, and one apical chloride anion. The EPR spectrum of 1 shows significant changes upon variation of the temperature, from a broad pseudo‐isotropic symmetry signal at 298 K (gav. = 2.16) to a signal characterized by an axially distorted CuII below 200 K (g∥ = 2.34; no A∥ resolved; g⟂ = 2.11). The green, dinuclear, oxalato‐bridged compound 2 is strongly antiferromagnetically coupled with 2J = –342 cm–1. Its EPR spectrum shows only a broad line (gav. = 2.12), which is ascribed to mononuclear impurities, as it does not disappear even at very low temperatures. No signal for a triplet of dinuclear CuII is observed at any temperature.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Synthesis and Reactions of Trifluorovinylferrocene
Authors: Roemer Max , Lentz Dieter
Published: September 2008

Trifluorovinylferrocene (1) is obtained in high yield by a Stille coupling of iodoferrocene with tributyltrifluorovinylstannane. [2+2] Cycloaddition of 1 yields the cyclobutane derivatives 2a and 2b under mild conditions. At higher temperature a defluoration reaction takes place yielding the cyclobutane derivative 3 under inert conditions whereas in the presence of air and water the cyclobuta‐1,2‐dion derivative 4 is formed presumably by an unusual hydrolysis of an aliphatic difluoromethylene group. Nucleophilic attack of the CF2 group of 1 yields specifically the trans isomer of 1,2‐Diferrocenyl‐1,2‐difluoroethene 5. The crystal and molecular structures of 1, 2a, 2b, 3 and 5 were elucidated by X‐ray diffraction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
New Fluorescent Calix Crown Ethers, Part II: Synthesis and Complex Formation in Solution and the Solid State
Authors: Stoll Ion , Brodbeck Ralf , Wiegmann Sebastian , Eberhard Jens , Kerruth Silke , Neumann Beate , Stammler Hans‐Georg , Mattay Jochen
Published: September 2008

New luminescent 1‐aza‐15‐crown‐5 ethers bearing a coumarin unit were synthesised leading to the cavitand‐based calix crown ether 9. The solid‐state structures of crown ethers 5 and 6 and the solid‐state structures of the sodium and potassium iodide complexes of crown ether 5 are presented. The association constants for the complex formation with alkali metal ions in methanol were determined. Only weak complexes were formed (KNa = 286 M–1, KK = 392 M–1). The aza‐15‐crown‐5 ether was attached by a methylene unit to a cavitand to give the new fluorescent calix crown ether 9. The association constants for the sodium and potassium complexes in methanol were investigated as well, and an enhancement for the association constant of the sodium complex was found (KNa = 1215 M–1, KK = 497 M–1). Selected equilibrium structures of the complexes of 9 were examined by Kohn–Sham density functional calculations to give a detailed understanding of the interplay between the two involved building blocks. Based on these results, a sidewise cation binding of the host 9 can be assumed. These complex geometries are distinct from our findings in our previous work for a larger crown ether attached to a cavitand.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
A New Class of Fluorescent Dye for Sensing Water in Organic Solvents by Photo‐Induced Electron Transfer – A (Phenylamino)naphtho[1,2‐d]oxazol‐2‐yl‐Type Fluorophore with both Proton‐Binding and Proton‐Donating Sites
Authors: Ooyama Yousuke , Egawa Haruka , Yoshida Katsuhira
Published: September 2008

A new class of fluorescent dye for sensing water in organic solvents by photo‐induced electron transfer (PET), based on a (phenylamino)naphtho[1,2‐d]oxazol‐2‐yl‐type fluorophore with both proton binding and proton donating sites, has been designed developed. The fluorophore exhibits a weak emission in organic solvents but a drastic enhancement in the fluorescence intensity is observed with increasing water content in organic solvents. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Domino Heck–Aza‐Michael Reactions: A One‐Pot, Sequential Three‐Component Approach to 1,1‐Dioxido‐1,2‐benzisothiazoline‐3‐acetic Acid
Authors: Rolfe Alan , Young Kyle , Hanson Paul R.
Published: September 2008

The development of a new method for the synthesis of 1,1‐dioxido‐1,2‐benzisothiazoline‐3‐acetic acid by a domino process is reported whereby a classical Heck reaction is coupled to an intramolecular aza‐Michael reaction. Ultimately, this method has been expanded to a one‐pot, sequential three‐component protocol to generate diverse benzofused γ‐sultams from a range of commercially available α‐bromobenzenesulfonyl chlorides, amines and Michael acceptors. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
2‐Methoxy‐Δ3‐1,3,4‐oxadiazoline, a Multipurpose Precursor for the Generation of a Carbene, an Ylide, or a Diazo Compound
Authors: Mieusset Jean‐Luc , Billing Peter , Abraham Michael , Arion Vladimir B. , Brecker Lothar , Brinker Udo H.
Published: September 2008

In the course of our investigation of the intermolecular reactions of foiled carbenes of the norborn‐2‐en‐7‐ylidene type, we have investigated the decomposition of methoxyoxadiazoline 1 in alcohols. Most of the reactions performed lead to products with an anti configuration confirming the participation of the double bond to the stabilization of the transition states. The thermal behavior of spirooxadiazoline 1 is quite different from the behavior of the parent 2‐methoxy‐2,5,5‐trimethyl‐Δ3‐1,3,4‐oxadiazoline. Photolysis of 1 leads to the carbene after prior formation of the diazo compound whereas thermolysis cleanly generates an extremely unstable carbonyl ylide 4 that immediately decomposes to the stabilized‐nucleophilic carbene 5 and methyl acetate without generation of 1‐methoxyethylidene. Both conformers of 4 do not interconvert and, therefore, they have different life times. Nevertheless, we were able to trap syn ylide 4a with methanol. Calculations show that nonbonding interactions between an alkyl carbene and an ester are more significant than ylide formation. Synthetically, photolysis of oxadiazoline 1 in ethyl acetate has proven to give anti ethers in excellent yields. Moreover, we report the first reactions of a norbornenylidene derivative with O–H bonds in which no products resulting from a cationic rearrangement are formed.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Power consequences of linkage disequilibrium variation between populations
Authors: Teo Yik Y. , Small Kerrin S. , Fry Andrew E. , Wu Yumeng , Kwiatkowski Dominic P. , Clark Taane G.
Published: September 2008

We quantify the degree to which LD differences exist in the human genome and investigates the consequences that variations in patterns of LD between populations can have on the power of case‐control or family‐trio association studies. Although only a small proportion of SNPs show significant LD differences (0.8–5%), these can introduce artificial signals of associations and reduce the power to detect true associations in case‐control designs, even when meta‐analytic approaches are used to account for stratification. We show that combining trios from different populations in the presence of significant LD differences can adversely affect power even though the number of trios has increased. Our results have implications on genetic studies conducted in populations with substantial population structure and show that the use of meta‐analytic approaches or family‐based designs to protect Type 1 error does not prevent loss of power due to differences in LD across populations. Genet. Epidemiol. 2008. © 2008 Wiley‐Liss, Inc.
Blocking the hedgehog pathway inhibits hepatoblastoma growth #
Authors: Eichenmüller Melanie , Gruner Ivonne , Hagl Beate , Häberle Beate , Müller-Höcker Josef , von Schweinitz Dietrich , Kappler Roland
Published: September 2008

Recent evidence has indicated that Hedgehog (Hh) signaling significantly contributes to liver development and regeneration and that activation of the pathway may contribute to growth of hepatocellular carcinoma (HCC) in adults. However, the role of Hh signaling in pediatric liver tumors remains to be elucidated. In this study, we show that Hh signaling is activated in hepatoblastoma (HB), the most common liver tumor in childhood, with most occurrences before the age of 3 years. The Hh target genes glioma-associated oncogene homolog 1 (GLI1) and Patched (PTCH1) showed increased transcript levels in 65% and 30% of HB samples, respectively, compared with normal liver tissues. Most interestingly, the gene encoding the hedgehog interacting protein (HHIP) is transcriptionally silenced by cytosine-phospho-guanosine (CpG) island promoter hypermethylation in 26% of HB cases and treatment with the DNA-demethylating agent 5-aza-2′-deoxycytidine partially restored HHIP expression. Blocking Hh signaling with the antagonist cyclopamine had a strong inhibitory effect on cell proliferation of HB cell lines with an activated pathway. We further demonstrate that this decrease in cell viability is caused by a massive induction of apoptosis, as shown by morphological changes and phosphatidylserine membrane asymmetry. In cyclopamine-exposed HB cells, caspase 3 and poly(adenosine diphosphate-ribose) polymerase proteins were specifically activated by their proteolytic cleavage. Conclusion: This study demonstrates, for the first time, the frequent occurrence of GLI1 and PTCH1 overexpression and HHIP promoter methylation in early childhood HB, thus indicating a key role for Hh signaling activation in the malignant transformation of embryonal liver cells. (Hepatology 2009;49:482–490.)
Deficiency in regulatory T cells results in development of antimitochondrial antibodies and autoimmune cholangitis #
Authors: Zhang Weici , Sharma Rahul , Ju Shyr-Te , He Xiao-Song , Tao Yanyan , Tsuneyama Koichi , Tian Zhigang , Lian Zhe-Xiong , Fu Shu Man , Gershwin Eric M.
Published: September 2008

There have been several descriptions of mouse models that manifest select immunological and clinical features of autoimmune cholangitis with similarities to primary biliary cirrhosis in humans. Some of these models require immunization with complete Freund's adjuvant, whereas others suggest that a decreased frequency of T regulatory cells (Tregs) facilitates spontaneous disease. We hypothesized that antimitochondrial antibodies (AMAs) and development of autoimmune cholangitis would be found in mice genetically deficient in components essential for the development and homeostasis of forkhead box 3 (Foxp3)+ Tregs. Therefore, we examined Scurfy (Sf) mice, animals that have a mutation in the gene encoding the Foxp3 transcription factor that results in a complete abolition of Foxp3+ Tregs. At 3 to 4 weeks of age, 100% of animals exhibit high-titer serum AMA of all isotypes. Furthermore, mice have moderate to severe lymphocytic infiltrates surrounding portal areas with evidence of biliary duct damage, and dramatic elevation of cytokines in serum and messenger RNAs encoding cytokines in liver tissue, including tumor necrosis factor α, interferon-γ, interleukin (IL)-6, IL-12, and IL-23. Conclusion: The lack of functional Foxp3 is a major predisposing feature for loss of tolerance that leads to autoimmune cholangitis. These findings reflect on the importance of regulatory T cells in other murine models as well as in patients with primary biliary cirrhosis. (Hepatology 2008.)
Autochthonous liver tumors induce systemic T cell tolerance associated with T cell receptor down-modulation #
Authors: Ney Jasmin T. , Schmidt Thomas , Kurts Christian , Zhou Qi , Eckert Dawid , Felsher Dean W. , Schorle Hubert , Knolle Percy , Tüting Thomas , Barchet Winfried , Büttner Reinhard , Limmer Andreas , Gütgemann Ines
Published: September 2008

The reason the adaptive immune system fails in advanced liver tumors is largely unclear. To address this question, we have developed a novel murine model that combines c-myc–induced autochthonous tumorigenesis with expression of a cognate antigen, ovalbumin (OVA). When c-myc/OVA transgenic mice were crossed with liver-specific inducer mice, multifocal hepatocellular carcinomas co-expressing OVA developed in a tetracycline-dependent manner with a short latency and 100% penetrance. Transferred OVA-specific T cells, although infiltrating the tumor at high numbers, were hyporesponsive, as evidenced by a lack of in vivo cytotoxicity and interferon gamma production. This allowed the tumor to progress even in the presence of large numbers of antigen-specific T cells and even after vaccination (OVA+CpG-DNA). Interestingly, T cell receptor down-modulation was observed, which may explain antigen-specific hyporesponsiveness. This model is helpful in understanding liver cancer–specific mechanisms of T cell tolerance and dissection of antigen-specific and nonspecific mechanisms of immunotherapies in the preclinical phase. (Hepatology 2009.)
Recruitment of host progenitor cells in rat liver transplants #
Authors: Sun Zhaoli , Zhang Xiuying , Locke Jayme E. , Zheng Qizhi , Tachibana Shingo , Diehl Anna Mae , Williams George Melville
Published: September 2008

Despite major histocompatibility complex incompatibility, liver transplants from Lewis rats to dark agouti (DA) rats survive indefinitely without immunosuppression, and the studies we report sought the mechanism(s) responsible for this. At 1 year, most of the liver reacted positively to host anti-DA antibody. When small (50%) grafts were transplanted, recruitment was more rapid because most of the organ assumed the host phenotype at 3 months. After transplantation, the Y chromosome was detected in the hepatocytes of XX to XY grafts by both in situ hybridization and polymerase chain reaction. Further, livers from transgenic Lewis rats carrying strong green fluorescent protein (GFP) markers lost the marker with time after transplantation to DA, GFP-negative hosts. Few liver cells contained the Y chromosome in syngeneic XX to XY liver grafts or when the hosts of Lewis XX to DA XY allografts were treated with cyclosporine A at 10 mg/kg/day. This dosage also impeded enlargement of the liver at 10 days. Using GFP-positive XX Lewis donors transplanted to GFP-negative XY DA hosts, we found little Y DNA in GFP-positive cells at 10 days. Host-derived OV-6–positive and c-kit–positive, albumin-positive cells were present at 3-10 days, but cells with the CD34 marker were less common and some clearly still had the donor phenotype at 10 days. Cells positive for chemokine cysteine-X-cysteine receptor-4 increased with time and were abundant 1 month after transplantation. We conclude: (1) extrahepatic cells can differentiate into liver tissues; (2) regenerative stimuli accelerate stem cell recruitment; (3) both regeneration and recruitment are impeded by cyclosporine A immunosuppression, and (4) donor GFP-positive cells contained little host Y chromosome after transplantation, suggesting that cell fusion was uncommon and, therefore, unlikely to be the mechanism leading to the changes in genotype and phenotype we observed. (Hepatology 2008.)
The tyrosine kinase receptor HER2 (erbB‐2): From oncogenesis to adipogenesis
Authors: Vazquez‐Martin Alejandro , Ortega‐Delgado Francisco Jose , Fernandez‐Real Jose Manuel , Menendez Javier A.
Published: September 2008

Recent experimental evidences begin to support the notion that the proto‐oncogene HER2 (erbB‐2) might unexpectedly function to modulate the adipogenic conversion of preadipocytes. Two opposing scenarios have been proposed, however, to explain the influence of HER2 on adipocyte differentiation. In one hand, down‐modulation of HER2 expression and pharmacological reduction of HER2 activity have been related to enhanced adipocyte differentiation. On the contrary, an increased abundance in HER2 has been described in differentiated adipocytes compared with preadipocytes. Considering that expression and activity of the lipogenic enzyme Fatty Acid Synthase (FASN) become up‐regulated during adipogenic conversion, we recently hypothesized that a “HER2 → FASN axis” ‐a “lipogenic benefit” that has been shown to enhance cancer cell proliferation, survival, chemoresistance and metastasis in biologically aggressive subgroups of breast carcinomas‐might also naturally work during the differentiation of preadipocytes. To definitely clarify if the discrepancy between the opposing theories for a role of HER2 during adipocyte differentiation related to the experimental approach utilized to compare the abundance of HER2 in undifferentiated and differentiated adipocytes (i.e., cell lysates containing equivalent protein content versus cell lysates generated from similar cell numbers), we here took advantage of a high content microscopy approach. Using an automated confocal imaging platform, we monitored the expression status of the adipogenic marker FASN and its timing relationship with HER2 not only in individual 3T3‐L1 cells but further in whole cultures of 3T3‐L1 preadipocytes undergoing adipogenic conversion. Our findings not only confirm a non‐oncogenic role for HER2 in the process of adipose differentiation but further suggest that HER2 might represent a previously unrecognized target to manage obesity via the lipogenic enzyme FASN. J. Cell. Biochem. 105: 1147–1152, 2008. © 2008 Wiley‐Liss, Inc.
The EphA3 receptor is expressed in a subset of rhabdomyosarcoma cell lines and suppresses cell adhesion and migration
Authors: Clifford Noretta , Smith Loraine M. , Powell James , Gattenlöhner Stefan , Marx Alexander , O'Connor Rosemary
Published: September 2008

Elevated expression of the Eph receptor tyrosine kinase EphA3 is associated with lymphocytic leukaemia, but little is known about its expression or function in solid tumours. Out of a panel of cancer cell lines, we found that EphA3 was expressed only on two rhabdomyosarcoma (RMS) cell lines of the embryonal histological subtype and on one of the alveolar RMS subtype, whereas it was not detected on two other cell lines of the alveolar subtype. Other EphA receptors (1–7) were, either not expressed in any, or expressed in all five RMS cell lines. Stimulation of EphA3‐expressing TE671 and RD RMS cells with ephrinA5 resulted in loss of adhesion to fibronectin, decreased migration towards the stromal cell‐derived growth factor‐I (SDF‐I), increased EphA3 phosphorylation, and increased Rho GTPase activity. In contrast, ectopic expression of EphA3 in the EphA3 negative CRL2061 cell line resulted in decreased cell adhesion. Finally, suppression of EphA3 expression by siRNA in RD cells results in increased SDF‐I‐mediated motility. These data indicate that EphA3 expression may define subsets of RMS tumours, and that EphA3 suppresses motility through regulation of Rho GTPases in RMS cells. J. Cell. Biochem. 105: 1250–1259, 2008. © 2008 Wiley‐Liss, Inc.
Elk‐1, CREB, and MKP‐1 regulate Egr‐1 expression in gonadotropin‐releasing hormone stimulated gonadotrophs
Authors: Mayer Sabine I. , Willars Gary B. , Nishida Eisuke , Thiel Gerald
Published: September 2008

Stimulation of gonadotropin‐releasing hormone (GnRH) receptors with the GnRH analogue buserelin enhances expression of the zinc finger transcription factor Egr‐1 in a pituitary gonadotroph cell line. The signaling cascade is blocked by overexpression of MAP kinase phosphatase‐1 that dephosphorylates extracellular signal‐regulated protein kinase in the nucleus. Chromatin immunoprecipitation experiments revealed that the phosphorylated form of Elk‐1, a key regulator of gene transcription driven by serum response element (SRE), binds to the 5′‐upstream region of the Egr‐1 gene in buserelin‐stimulated gonadotrophs. Expression of a dominant‐negative mutant of Elk‐1 completely blocked Egr‐1 expression, indicating that Elk‐1 connects the intracellular signaling cascade elicited by activation of GnRH receptors with transcription of the Egr‐1 gene. GnRH receptor activation additionally induced the phosphorylation of CREB, which in its phosphorylated form bound to the Egr‐1 gene. Expression of a dominant‐negative mutant of CREB reduced GnRH receptor‐induced upregulation of Egr‐1 expression, indicating that CREB plays a role in the signaling pathway that regulates Egr‐1 expression in gonadotrophs. We further identified the genes encoding basic fibroblast growth factor, tumor necrosis factor α, and transforming growth factor β as bona fide target genes of Egr‐1 in gonadotrophs. The analysis of gonadotroph cells that express—in addition to GnRH receptors—muscarinic M3 acetylcholine receptors revealed that the nuclear events connecting GnRH receptors and muscarinic M3 acetylcholine receptors with the Egr‐1 gene are indistinguishable. J. Cell. Biochem. 105: 1267–1278, 2008. © 2008 Wiley‐Liss, Inc.
Modulation of mouse RANKL gene expression by Runx2 and vitamin D3
Authors: Kitazawa Riko , Mori Kiyoshi , Yamaguchi Akira , Kondo Takeshi , Kitazawa Sohei
Published: September 2008

The expression of receptor activator of nuclear factor‐κB ligand (RANKL) is regulated by bone‐seeking hormones such as PTH and 1α,25‐dihydroxyvitamin D3 (1,25(OH)2D3). Runx2, a master gene for osteoblastic differentiation, also modulates osteoclastogenesis by regulating the RANKL gene. To elucidate the mechanism whereby runx2 and 1,25(OH)2D3 regulate RANKL expression, we studied the function of runx2 on the chromatin structure and on the proximal binding sites using osteoblastic cell lines derived from normal (ST2) and runx2‐deficient mice (RD‐C6). Although the expression of RANKL in the steady‐state was higher in RD‐C6 than in ST2, 1,25(OH)2D3‐treatment of the cells increased it 20‐fold in ST2 but only 1.8‐fold in RD‐C6. Transient transfection studies with proximal RANKL 2kb promoter, runx2 knock‐down in ST2, and forced expression of runx2 in RD‐C6 all confirmed that runx2 set the steady‐state expression of the RANKL gene at a low level, but exerted a positive effect on enhanced transcriptional activity in response to 1,25(OH)2D3. Also, assessment of the acetylation status of the area spanning 40 kb upstream of the basic promoter in ST2 and RD‐C6 by ChIP assay revealed that whereas H3 and H4 histone acetylation was detected even in the steady‐state in RD‐C6, it was detected only with 1,25(OH)2D3 in ST2. In the steady‐state, runx2 may suppress RANKL gene by condensing the chromatin structure; however, it exerts a positive effect on 1,25(OH)2D3‐induced RANKL transcription when the proximal runx2 sites are accessible. Thus, RANKL expression in stromal/osteoblastic cells is keenly regulated by 1,25(OH)2D3 which transactivates the gene at two different levels. J. Cell. Biochem. 105: 1289–1297, 2008. © 2008 Wiley‐Liss, Inc.
Lanthanum enhances in vitro osteoblast differentiation via pertussis toxin‐sensitive gi protein and ERK signaling pathway
Authors: Wang Xi , Yuan Lan , Huang Jian , Zhang Tian‐Lan , Wang Kui
Published: September 2008

Converging lines of evidence suggest that lanthanum tends to deposit in bone. The influence of lanthanum ion (La3+) on osteoblast differentiation and the related mechanism are essential to understanding its effect on bone metabolism. In this study, La3+ treatment enhanced in vitro osteoblast differentiation as evidenced by promoting alkaline phosphatase (ALP) activity, osteocalcin (OC) secretion, and matrix mineralization. The expressions of osteoblast‐specific genes of Cbfa‐1, osteopontin (OPN), and bone sialoprotein (BSP) were all increased in the presence of La3+, but no change was observed in that of type I collagen (COL‐I). Further studies demonstrated that La3+ treatment enhanced phosphorylation of extracellular signal‐regulated kinase (ERK). Inhibition of ERK activation by U0126 suppressed the effects of La3+ on osteoblast activity. Moreover, pretreatment of the cells with pertussis toxin (PTx), a Gi protein inhibitor, suppressed the La3+‐enhanced ERK phosphorylation and osteoblast differentiation. These findings suggest that La3+ exposure enhances in vitro osteoblast differentiation and the effect depends on ERK phosphorylation via PTx‐sensitive Gi protein signaling. J. Cell. Biochem. 105: 1307–1315, 2008. © 2008 Wiley‐Liss, Inc.
Cross‐regulation between distinct natural killer T cell subsets influences immune response to self and foreign antigens
Authors: Arrenberg Philomena , Halder Ramesh , Kumar Vipin
Published: September 2008

Natural killer T (NKT) cells generally recognize lipid‐antigens presented in the context of the MHC class I‐like molecule CD1d. CD1d‐restricted NKT cells consist of two broad subsets: Type I, which express an invariant T cell receptor (TCR) and type II, which utilize diverse TCR gene segments. A major type II NKT subset has been shown to recognize a self‐glycolipid, sulfatide. Both subsets play important roles in autoimmune diseases, tumor surveillance, and infectious diseases. While type I NKT cells protect from tumor growth by enhancing tumor surveillance, type II NKT cells may suppress anti‐tumor immune responses. In a murine autoimmune hepatitis model, type I NKT cells contribute to pathogenesis, whereas activation of sulfatide‐reactive type II NKT cells protects from disease. Sulfatide‐mediated activation of type II NKT cells results in modification of dendritic cells and induction of anergy in type I NKT cells. Elucidation of this novel pathway of cross‐regulation among NKT cell subsets will provide tools for intervention in autoimmune diseases and for designing strategies for effective anti‐tumor immunity. J. Cell. Physiol. 218: 246–250, 2009. © 2008 Wiley‐Liss, Inc.
Time‐dependent, anisotropic pore structure and soil strength in a 10‐year period after intensive tractor wheeling under conservation and conventional tillage
Authors: Peng Xinhua , Horn Rainer
Published: September 2008

Any soil deformation induced by agricultural machinery is transmitted three‐dimensionally and the “kneading effect” of tractor wheeling further rearranges soil particles and aggregates anisotropically. In this work, we investigated how heterogeneous soil structure remained 10 y after a complete wheeling of fields in 1995 with a single pass of 2 × 2.5 Mg and of 6 × 5 Mg on a silty loam Luvisol derived from loess. Control plots received no tractor wheeling. We also analyzed how soil physical properties responded to the tractor wheeling under two management systems: continuous conservation tillage (chisel plow = CS) with mulch cover and conventional tillage (plowing to 25 cm depth annually = CT).

We compared three sampling dates: done before wheeling in 1995, after wheeling in 1995, and in 2004. Results showed that applying tractor wheeling in 1995 not only reduced total soil‐pore volume but also increased soil strength as expressed by precompression stress. The reduction of total pore volume at 30 cm depth was more pronounced in CS than in CT. After 10 y of continuous use of the two tillage systems, the precompression stress of the wheeled soils was greater in the vertical direction than in the horizontal direction. This anisotropy of soil strength and its load dependency were also more pronounced in CS than in CT. The effect of wheeling on the fluxes of gas and water was covered up by the effects of biochannels, causing a prevailing vertical passage. From this study, we conclude that heavy, agricultural machinery causes soil degradation, which is more evident in CS than in CT.
Chemical and organic immobilization treatments for reducing phytoavailability of heavy metals in copper‐mine tailings
Authors: Jamal Khan Mohammad , Jones David L.
Published: September 2008

This study was conducted to evaluate the efficiency of diammonium phosphate (DAP), agricultural limestone (lime), and green‐waste compost mixed with 30% treated sewage sludge (GCS) applied alone or in combination as chemical immobilization treatment using tomato as a test crop. Mine waste was collected from an abandoned copper‐mine tailing site at Mynydd Parys, Anglesey (UK). Lime was applied at the rate of CaCO3 equivalent (CCE, pH = 7), DAP at the rate of 23 g P per kg substrate, and 10% by weight, GCS as sole application. Half rate of each amendment was also tested as a combined treatment and an untreated substrate (control). Plant‐available metals (Cd, Cu, Fe, Pb, and Zn) were measured in substrate with conventional diethylenetriaminepentaacetic acid (DTPA) and sequential Ca(NO3)2 extraction. Plant–dry biomass yield was significantly (p < 0.001) increased by the combined application of all the three amendments while sole application of DAP reduced yield by 4‐fold compared to unamended soil probably due to P toxicity. Addition of lime reduced the DTPA‐extractable Cu, Fe, and Zn by 75%, 81%, and 85%, respectively, while Pb availability was reduced by 88% in combined DAP + lime + GCS treatment compared to control. The extraction capacity of DTPA was higher than that of Ca(NO3)2 by 3‐fold for Cu and Fe, 8‐fold for Pb, and 2‐fold for Zn. The leaf‐tissue concentrations of Cu and Fe were reduced by 77% and 83% in the lime + GCS amendment, respectively, while both Pb and Zn were reduced by 89% and 33%, respectively, in substrate treated with the combined application of all three amendments. These results suggest that alkaline amendments (both lime and GCS) were effective in reducing the phytoavailability of Cu, Fe, and Zn while DAP mixed with either GCS or lime was effective in reducing Pb availability.
Improved RP‐HPLC and anion‐exchange chromatography methods for the determination of amino acids and carbohydrates in soil solutions
Authors: Meyer Axel , Fischer Holger , Kuzyakov Yakov , Fischer Klaus
Published: September 2008

In spite of their low concentrations in soil solutions, low–molecular weight organic substances (LMWOS) such as amino acids, sugars, and uronic acids play a major role in the cycles of C and N in soil. With respect to their low concentrations and to possible matrix interferences, their analysis in soil leachates is a challenging task. We established two HPLC (high‐performance liquid chromatography) methods for the parallel determination of amino acids and carbohydrates in soil leachates. The pre‐column derivatization of amino acids with an o‐phthaldialdehyde (OPA) mercaptoethanol solution yields quantitation limits between 0.03 and 0.44 µmol L–1 and SD values of <8.3% (n = 9). High‐performance anion‐exchange chromatography (HPAEC) on a Dionex CarboPac PA 20 column with a NaOH acetate gradient combined with pulsed amperometric detection (PAD) was used for the determination of carbohydrates. The calibration curves obtained for 11 carbohydrates showed excellent linearity over the concentration range from 0.02 to 50.0 mg L–1. Recovery studies revealed good results for all analytes (89%–108%). Interferences from Hg(II) salts and chloroform used for stabilization of the leachates did not occur with both chromatographic methods. The optimized method was successfully used for quantitative determinations of amino acids and carbohydrates in soil leachates.
Enantioseparation of nuarimol by affinity electrokinetic chromatography‐partial filling technique using human serum albumin as chiral selector
Authors: Martínez‐Gómez Maria Amparo , Escuder‐Gilabert Laura , Villanueva‐Camañas Rosa M. , Sagrado Salvador , Medina‐Hernández Maria J.
Published: September 2008

The present paper deals with the enantiomeric separation of nuarimol enantiomers by affinity EKC‐partial filling technique using HSA as chiral selector. Firstly, a study of nuarimol interactions with HSA by CE‐frontal analysis was performed. The binding parameters obtained for the first site of interaction were n1 = 0.84; K1 = 9.7 ± 0.3×103 M–1 and the protein binding percentage of nuarimol at physiological concentration of HSA was 75.2 ± 0.2%. Due to the moderate affinity of nuarimol towards HSA the possibility of using this protein as chiral selector for the separation of nuarimol using the partial filling technique was evaluated. A multivariate optimization approach of the most critical experimental variables in enantioresolution, running pH, HSA concentration and plug length was carried out. Separation of nuarimol enantiomers was obtained under the following selected conditions: electrophoretic buffer composed of 50 mM Tris at pH 7.3; 160 μM HSA solution applied at 50 mbar for 156 s as chiral selector; nuarimol solutions in the range of 2–8×10–4 M injected hydrodynamically at 30 mbar for 2 s and the electrophoretic runs performed at 30°C applying 15 kV voltage. Resolution, accuracy, reproducibility speed and cost of the proposed method make it suitable for quality control of the enantiomeric composition of nuarimol in formulations and for further toxicological studies. The results showed a different affinity between nuarimol enantiomers towards HSA.
Biodegradable Nanogels Prepared by Self‐Assembly of Poly(L‐lactide)‐Grafted Dextran: Entrapment and Release of Proteins
Authors: Nagahama Koji , Ouchi Tatsuro , Ohya Yuichi
Published: September 2008

We showed previously that poly(L‐lactide)‐grafted dextran could form biodegradable nanogels in water. In this paper, various properties of Dex‐g‐PLLA nanogels were compared with Dex‐Chol (dextran‐cholesterol conjugate) nanogels to investigate the effects of hydrophobic units. Dex‐g‐PLLA nanogels exhibited significantly lower CAC and higher colloidal stability, indicating a strong tendency to form nanogels. We prepared lysozyme‐loaded Dex‐g‐PLLA nanogels, and they exhibited a sustained release of lysozyme for 1 week without denaturation in PBS at 37 °C. The Dex‐g‐PLLA nanogels therefore have great potential as a delivery vehicle for therapeutic protein.

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Polyarylene Synthesis by Suzuki Polycondensation of Aryl Dichlorides and an Aryl Diboronic Acid Ester
Authors: Kandre Ramchandra , Schlüter A. Dieter
Published: September 2008

This paper describes the successful application of the Suzuki polycondensation (SPC) to the synthesis of high molecular weight polyphenylenes using aryl dichloride monomers. From readily available starting material, two meta‐dichloromonomers (2b and 2c) were prepared and subjected to SPC with benzene 1,4‐diboronic acid ester to produce reasonably high molar mass poly(para‐meta‐phenylene)s 4a and 4b, respectively, if freshly prepared Pd‐catalyst, Buchwald ligand and the base K3PO4 were used. The polymer with butoxy substituent (4a) was compared regarding GPC molar mass and glass transition temperature with its exact same congener which had been synthesized in a previous work starting from a meta‐dibromo monomer. This comparison unequivocally confirms the molar masses achieved and, thus, establishes the first reported case of a SPC using aryl chloride monomers, instead of the more expensive and less amply available aryl bromides which had to be used otherwise.

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