bluuebunny/crossref_metadata_2025 huggingface dataset:
C‐(2‐Chloroquinoline‐3‐yl)‐N‐phenyl Nitrone: New Synthetic Antioxidant Inhibits Proliferation and Induces Apoptosis of Breast Carcinoma MCF‐7 Cells
Authors: Ramadan Mohamed , Gamal‐Eldeen Amira M. , Abdel‐Aziz Mohamed , Abuo‐Rahma Gamal El‐Din , Abdel‐Nabi Hisham , Nagib Abdel‐Hamid
Published: April 2006

In this work, a new quinoline nitrone derivative, C‐(2‐chloroquinoline‐3‐yl)‐N‐phenyl nitrone (CQPN) was successfully prepared and proved by spectral analysis. The antioxidant activity of CQPN against various radicals was investigated and its anti‐cancer properties against different human tumor cell lines including the solid tumor cell lines hepatocarcinoma (Hep‐G2) and breast carcinoma (MCF‐7); the hematopoietic tumor cell line lymphoblastic leukemia (1301) was also explored. CQPN activities were compared to that of the known nitrone C‐phenyl‐N‐tert‐butyl nitrone (PBN). Our results showed that although PBN was the stronger antioxidant than CQPN, the latter was an effective scavenger of different non‐physiological (1,1‐diphenyl‐2‐picrylhyrazyl) and physiological (peroxyl and hydroxyl) radicals. Both of CQPN and PBN possess a significant inhibitory property against LPS‐stimulated NO production in macrophage. CQPN and PBN treatment resulted in a growth inhibition in Hep‐G2 cells (IC50 31.42 μM and 18.6 μM, respectively). Unlike PBN, CQPN strongly inhibited the growth of MCF‐7 cells (IC50 14.01 μM) in a dose‐dependent manner. On contrary, CQPN and PBN exhibited a proliferative stimulatory activity of the immune cells including macrophages and lymphocytes. Exploring the cytotoxic effect of CQPN against MCF‐7 cells indicated that CQPN led to a major time‐dependent disturbance in the cell‐cycle phases including progressive arrest in both S‐ and G2/M‐phases. This disturbance was found to be associated with a kinetic induction of apoptosis. The novel nitrone derivative CQPN is a strong antioxidant, though less than PBN, and it may be an effective anti‐proliferative compound against breast carcinoma.
Investigation of the potential pharmacokinetic and pharmaco‐dynamic drug interaction between AHN 1‐055, a potent benztropine analog used for cocaine abuse, and cocaine after dosing in rats using intracerebral microdialysis
Authors: Raje Sangeeta , Cornish Jennifer , Newman Amy H. , Cao Jianjing , Katz Jonathan L. , Eddington Natalie D.
Published: April 2006

Purpose. AHN 1‐055, a benztropine (BZT) analog, binds with high affinity to the dopamine transporter (DAT), possesses behavioral, pharmacokinetic (PK) and brain microdialysate dopamine (DA) profiles distinct from cocaine. Accordingly, the objectives of this study were to evaluate the pharmacokinetics and dopamine release of AHN 1‐055, in the presence of cocaine.Methods. Male Sprague Dawley rats (∼300 g) were administered 5 mg/kg of AHN 1‐055 and cocaine i.v. and blood and brain samples were collected over 36 h. In addition, dialysis probes were stereotaxically implanted into the nucleus accumbens and extracellular fluid (ECF) DA levels were measured. PK and PD models were used to describe the relationship between the AHN 1‐055, cocaine and DA levels.Results. No significant (p<0.05) differences were found in the PK parameters of AHN 1‐055 alone (Vdss=18.7 l/kg,Cl=1.8 l/h/kg andt1/2=7.69 h) or AHN 1‐055 with cocaine (Vdss=17.4 l/kg,Cl=1.9 l/h/kg andt1/2=6.82 h). The brain‐to‐plasma (B/P) ratios (B/PAHN 1−055=4.8 vs B/Pwith cocaine=4.4) and half‐lives (t1/2(AHN 1−055)=6.2 h vst1/2(cocaine)=5.6 h for AHN 1‐055 alone and with cocaine were comparable. AHN 1‐055 DA profiles were significantly different after co‐administration with cocaine. There were no differences in theIC50for AHN 1‐055, with cocaine, however, theIC50for cocaine was significantly reduced with AHN 1‐055.Conclusions. The PK parameters of AHN 1‐055 were not changed, however, the effect on DA levels was affected when cocaine was administered with AHNDA profile is affected when dosed with cocaine. This latter effect is a desirable attribute in the development of a medication as a potential substitute therapeutic medication for the treatment of cocaine abuse. Copyright © 2006 John Wiley & Sons, Ltd.
Effects of enzyme inducers and inhibitors on the pharmacokinetics of intravenous omeprazole in rats
Authors: Lee Dae Y. , Shin Hyun S. , Bae Soo K. , Lee Myung G.
Published: April 2006

A series of experiments using various inducers and inhibitors of the hepatic microsomal cytochrome P450 (CYP) isozymes were conducted to find CYP isozymes responsible for the metabolism of omeprazole in male Sprague–Dawley rats. Omeprazole, 20 mg/kg, was administered intravenously. In rats pretreated with SKF 525‐A (a nonspecific CYP isozyme inhibitor in rats), the time‐averaged nonrenal clearance (Clnr) was significantly slower (77.1% decrease) than that in untreated rats. This indicated that omeprazole is metabolized via CYP isozymes in rats. Hence, rats were pretreated with various enzyme inducers and inhibitors. In rats pretreated with 3‐methylcholanthrene and dexamethasone (main inducers of CYP1A1/2 and 3A1/2 in rats, respectively), theClnrvalues were significantly faster (43.8% and 26.3% increase, respectively). In rats pretreated with troleandomycin and quinine (main inhibitors of CYP3A1/2 and 2D1 in rats, respectively), theClnrvalues were significantly slower (20.9% and 12.9% decrease, respectively). However, theClnrvalues were not significantly different in rats pretreated with orphenadrine, isoniazid and sulfaphenazole (main inducers of CYP2B1/2 and 2E1, and a main inhibitor of 2C11, respectively, in rats) compared with those of respective control rats. The above data suggested that omeprazole could be mainly metabolized via CYP1A1/2, 3A1/2 and 2D1 in male rats. Copyright © 2006 John Wiley & Sons, Ltd.
Rat strain differences in stereospecific 2‐oxidation of RS‐8359, a reversible and selective MAO‐A inhibitor, by aldehyde oxidase
Authors: Sasaki Takamitsu , Masubuchi Akiko , Yamamura Mayumi , Watanabe Nobuaki , Hiratsuka Masahiro , Mizugaki Michinao , Itoh Kunio , Tanaka Yorihisa
Published: April 2006

Aldehyde oxidase catalysed 2‐oxidation activity of the (S)‐enantiomer of RS‐8359, a selective and reversible monoamine oxidase A (MAO‐A) inhibitor, was investigated in liver cytosolic fractions from ten rat strains. Remarkably large strain differences were observed with approximately a 230 variation between the highest activity in the Wistar‐Imamichi strain and the lowest activity in the Slc:Wistar strain. The activities of Crj:SD and Slc:SD strain rats were considerably low, and that of the F344/DuCrj strain was very low. Among six Wistar strains, Crj:Wistar, Slc:Wistar, WKY/Izm, WKAH/Hkm, Jcl:Wistar and Wistar‐Imamichi, the Slc:Wistar strain rats showed exceptionally low 2‐oxidation activity that was comparable to that of the F344/DuCrj strain. The rat strain differences in the catalytic activity of aldehyde oxidase could correlate in part with the expressed levels of protein based on the mRNA of aldehyde oxidase. However, no small discrepancy existed in the almost negligible catalytic activity and the fairly high expression levels of protein and mRNA in the F344/DuCrj and Slc:Wistar strain rats. Some genetic factors might possibly be one of reasons for the discrepancy. Copyright © 2006 John Wiley & Sons, Ltd.
Bioavailability of an extemporaneous suspension of propafenone made from tablets
Authors: Olguín Hugo Juárez , Pérez Carmen Flores , Pérez Janett Flores , Mendiola Blanca Ramírez , Portugal Miriam Carrasco , Chávez Jesús Bobadilla
Published: April 2006

Propafenone is an effective antiarrhythmic agent used in children, while in Mexico no specific formulation for children is available, which causes errors in adequate dosage. The aim of this study was to determine the bioavailability of a suspension prepared extemporaneously using commercial tablets of propafenone. The bioavailability was determined in two groups of rabbits (n = 8): the first group received a single intravenous dose of 2 mg/kg of propafenone; the second was orally administered an extemporaneous suspension of propafenone prepared from commercial tablets. Blood samples were drawn at several times during the next 24 h and analysed by HPLC to determine drug levels. The extemporaneous suspension was tested previously with satisfactory results regarding physicochemical and microbiologic stability. The area under the curve (AUC) for the i.v. route was 5600.6 ng/ml.h and for oral administration the AUC was 3327.6 ng/ml.h. The bioavailability was calculated at 59.41%. These results are consistent with previous reports for solid dosage forms. The propafenone suspension prepared extemporaneously using commercial tablets is bioavailable using an animal model; nevertheless, it is necessary to carry out human studies either in volunteers or in patients to confirm these results. Copyright © 2006 John Wiley & Sons, Ltd.
The dampening effect of uncertainty on positive and negative emotions
Authors: van Dijk Eric , Zeelenberg Marcel
Published: April 2006

In this article we investigate how uncertainty about outcomes affects feelings with respect to these outcomes. The results of two experimental studies suggest that uncertainty about positive outcomes (Experiment 1) and negative outcomes (Experiment 2) leads to a dampening of emotions that are felt in response to these outcomes. The results are interpreted in terms of the ‘disjunction effect’ (Shafir & Tversky, 1992; Tversky & Shafir, 1992). Copyright © 2006 John Wiley & Sons, Ltd.
Regret in economic and psychological theories of choice
Authors: Connolly Terry , Butler David
Published: April 2006

Numerous studies have shown that choice can be influenced by expectations of regret or disappointment (or, for positive outcomes, of rejoicing or elation). Psychological researchers measure these expectations with self‐report instruments, economists infer them from observed choice behavior. The present study examines whether the emotion postulates embodied in economic choice models correspond to expected and experienced emotions as measured by self‐report. In a laboratory study (n = 50) of student participants playing real‐money lotteries, we included questionnaire measures of expected emotions for each possible lottery outcome. These emotion measures are reliable and well behaved, and modestly predictive of actual choices. They did not, however, conform well to the specific postulates of economic choice models, though they did show some of the juxtaposition effects proposed in such models. Emotional reactions to decision outcomes may be better characterized by broad measures of positive and negative affect than as nuanced mixtures of distinct emotions. Copyright © 2006 John Wiley & Sons, Ltd.
Portrait of the angry decision maker: how appraisal tendencies shape anger's influence on cognition
Authors: Lerner Jennifer S. , Tiedens Larissa Z.
Published: April 2006

This paper reviews the impact of anger on judgment and decision making. Section I proposes that anger merits special attention in the study of judgment and decision making because the effects of anger often diverge from those of other negative emotions. Section II presents an Appraisal‐Tendency Framework for predicting and organizing such effects. Section III reviews empirical evidence for the uniqueness of anger's relations to judgment and decision making. Section IV connects the Appraisal‐Tendency Framework to associated mechanisms and theories. Drawing on the evidence, Section V presents the question of whether anger should be considered a positive emotion. It also proposes the hypothesis that anger will be experienced as relatively unpleasant and unrewarding when reflecting back on the source of one's anger but experienced as relatively pleasant and rewarding when looking forward. Section VI synthesizes the evidence into a new portrait of the angry decision maker. Copyright © 2006 John Wiley & Sons, Ltd.
Visceral influences on risk‐taking behavior
Authors: Ditto Peter H. , Pizarro David A. , Epstein Eden B. , Jacobson Jill A. , MacDonald Tara K.
Published: April 2006

Visceral cues indicating proximity to objects of desire can lead people to be disproportionately influenced by the anticipated rewards of immediate gratification rather than the risks of consummatory behavior. Two studies examined this hypothesis. In Study 1, participants were given the choice of playing a game in which they risked time in the lab to win chocolate chip cookies. Participants who could see and smell the cookies while they made their decision were less sensitive to risk information than were participants for whom the cookies were merely described. In Study 2, male condom users either saw a video or read a description depicting a young couple deciding whether to have sex without a condom. Participants seeing the video expressed a greater likelihood of having unprotected sex in the situation than did participants reading the description. The underappreciated role of visceral factors in social cognition theory and research is discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Affect and decision making: a “hot” topic
Authors: Peters Ellen , Västfjäll Daniel , Gärling Tommy , Slovic Paul
Published: April 2006

The seven papers in this special issue represent the breadth and complexity of approaches to the study of affect in judgment and decision processes. Four papers examine the role of arousal or specific emotions in decision making. The three other papers investigate the impacts of uncertainty, time course, and thinking about mood. We briefly describe four functions of affect in decision making (affect as information, as a spotlight, as a motivator, and as common currency) and relate them to the seven special‐issue papers. The role of affect in decisions and decision processes is quite nuanced and deserves careful empirical study in basic and applied research. Copyright © 2006 John Wiley & Sons, Ltd.
Expression of folate pathway genes in the cartilage ofHoxd4andHoxc8transgenic mice
Authors: Kruger Claudia , Talmadge Catherine , Kappen Claudia
Published: April 2006

BACKGROUND

Hox transcription factors are well known for their role in skeletal patterning in vertebrates. They regulate gene expression during the development of cartilage, the precursor to mature bone. We previously reported that overexpression of the homeobox genesHoxc8andHoxd4results in severe cartilage defects, reduced proteoglycan content, accumulation of immature chondrocytes, and decreased maturation to hypertrophy. We have also shown thatHoxd4transgenic mice whose diets were supplemented with folate had their skeletal development restored. Since folate is required for growth and differentiation of chondrocytes, we hypothesized that the beneficial effect of folate inHoxd4transgenic mice might indicate a local deficiency in folate utilization, possibly caused by deregulation of genes encoding folate transport proteins or folate metabolic enzymes.

METHODS

We assayed the prevalence of transcripts for 22 folate transport proteins and metabolizing enzymes, here collectively referred to as folate pathway genes. Quantitative real‐time PCR was performed on cDNA samples derived from RNA isolated from primary chondrocytes of individual rib cartilages fromHoxd4andHoxc8transgenic mice, respectively.

RESULTS

This study shows that theHoxtransgenes produce overexpression ofHoxd4andHoxc8in primary chondrocytes from perinatal transgenic mice. However, no differences were found in expression levels of the folate pathway genes in transgenic cells compared to littermate controls.

CONCLUSIONS

Our results provide evidence that folate pathway genes are only indirect targets ofHoxtransgene overexpression in our transgenic animals. These expression studies provide a baseline for future studies into the role of folate metabolism in chondrocyte differentiation. Birth Defects Research (Part A), 2006. © 2006 Wiley‐Liss, Inc.
Supramolecular Hybrids of [60]Fullerene and Single‐Wall Carbon Nanotubes
Authors: Guldi Dirk M. , Menna Enzo , Maggini Michele , Marcaccio Massimo , Paolucci Demis , Paolucci Francesco , Campidelli Stéphane , Prato Maurizio , Rahman G. M. Aminur , Schergna Stefano
Published: April 2006

Noncovalent interactions between purified HiPCO single‐wall carbon nanotubes (SWNT) and a [60]fullerene–pyrene dyad, synthesized through a regioselective double‐cyclopropanation process, produce stable suspensions in which the tubes are very well dispersed, as evidenced by microscopy characterization. Cyclic voltammetry experiments and photophysical characterization of the suspensions in organic solvents are all indicative of sizeable interactions of the pyrene moiety with the SWNT and, therefore, of the prevalence in solution of [60]fullerene–pyrene⋅SWNT hybrids.
MRI tumor characterization using Gd‐GlyMe‐DOTA‐perfluorooctyl‐mannose‐conjugate (Gadofluorine M™), a protein‐avid contrast agent
Authors: Raatschen Hans‐Jürgen , Swain Rebecca , Shames David M. , Fu Yanjun , Boyd Zachary , Zierhut Matthew L. , Wendland Michael F. , Misselwitz Bernd , Weinmann Hanns‐Joachim , Wolf Karl‐Jürgen , Brasch Robert C.
Published: April 2006

The rationale and objectives were to define the MRI tumor‐characterizing potential of a new protein‐avid contrast agent, Gd‐GlyMe‐DOTA‐perfluorooctyl‐mannose‐conjugate (Gadofluorine M™; Schering AG, Berlin, Germany) in a chemically induced tumor model of varying malignancy. Because of the tendency for this agent to form large micelles in water and to bind strongly to hydrophobic sites on proteins, it was hypothesized that patterns of dynamic tumor enhancement could be used to differentiate benign from malignant lesions, to grade the severity of malignancies and to define areas of tumor necrosis. Gadofluorine M, 0.05 mmol Gd kg−1, was administered intravenously to 28 anesthetized rats that had developed over 10 months mammary tumors of varying degrees of malignancy as a consequence of intraperitoneal administration of N‐ethyl‐N‐nitrosourea (ENU), 45–250 mg kg−1. These tumors ranged histologically from benign fibroadenomas to highly undifferentiated adenocarcinomas. Dynamic enhancement data were analyzed kinetically using a two‐compartment tumor model to generate estimates of fractional plasma volume (fPV), apparent fractional extracellular volume (fEV*) and an endothelial transfer coefficient (KPS) for this contrast agent. Tumors were examined microscopically for tumor type, degree of malignancy (Scarff–Bloom–Richardson score) and location of necrosis. Eighteen tumor‐bearing rats were successfully imaged. MRI data showed an immediate strong and gradually increasing tumor enhancement. KPS and fEV*, but not fPV obtained from tumors correlated significantly (p < 0.05) with the SBR tumor grade, r = 0.65 and 0.56, respectively. Estimates for KPS and fEV* but not fPV were significantly lower in a group consisting of benign and low‐grade malignant tumors compared with the group of less‐differentiated high‐grade tumors (1.61 ± 0.64 vs 3.37 ± 1.49, p < 0.01; 0.45 ± 0.17 vs 0.78 ± 0.24, p < 0.01; and 0.076 ± 0.048 vs 0.121 ± 0.088, p = 0.24, respectively). It is concluded that the protein‐avid MRI contrast agent Gadofluorine M enhances tumors of varying malignancy depending on the tumor grade, higher contrast agent accumulation for more malignant lesions. The results show potential utility for differentiating benign and low‐grade malignant lesions from high‐grade cancers. Copyright © 2006 John Wiley & Sons, Ltd.
Phase II clinical studies of denileukin diftitox diphtheria toxin fusion protein in patients with previously treated chronic lymphocytic leukemia
Authors: Frankel Arthur E. , Surendranathan Asha , Black Jennifer H. , White Angela , Ganjoo Kristen , Cripe Larry D.
Published: April 2006

BACKGROUND

The safety and efficacy of the interleukin‐2 diphtheria toxin fusion protein (DAB389IL2; denileukin diftitox) directed against the IL‐2 receptor (IL‐2R) was tested in patients with recurrent or refractory chronic lymphocytic leukemia (CLL).

METHODS

Denileukin diftitox was administered as 60‐minute intravenous infusions for 5 days every 21 days at a dose of 18 μg/kg per day for up to 8 cycles. In total, 28 patients were treated in 2 multiinstitutional studies with similar eligibility criteria and treatment protocols. Twenty‐two patients receive ≥2 cycles of denileukin diftitox and were evaluable for response.

RESULTS

Twelve of 22 patients achieved reductions of peripheral CLL cells, with 5 of 12 patients achieving >80% reductions. Six of 22 patients achieved reductions in the size of lymph node on examination and computed tomography scans, and all 6 of those patients met the criteria for a partial or complete response that lasted ≥2 months. Bone marrow biopsies before and after treatment confirmed a complete remission that lasted for 1 year in 1 patient. Overall, denileukin diftitox produced complete remission in 1 of 22 patients (4%) and partial remission in 5 of 22 patients (23%) for a total remission rate of 27%. Progression‐free intervals in the responders were 2 months in 2 patients and 4 months, 6 months, 7 months, and 12 months in 1 patient each. Toxicities were moderate. No infections associated with immunosuppression were seen. There was no significant correlation of response or toxicities with the numbers of denileukin diftitox cycles received or with CD25 levels.

CONCLUSIONS

Follow‐up studies will be required to identify predictors of response that may improve the response rate to denileukin diftitox in patients with CLL. Cancer 2006. © 2006 American Cancer Society.
Patterns of exercise across the cancer trajectory in brain tumor patients
Authors: Jones Lee W. , Guill Bebe , Keir Stephen T. , Carter B.S. Karen , Friedman Henry S. , Bigner Darrell D. , Reardon David A.
Published: April 2006

BACKGROUND

Exercise may represent a supportive intervention that may complement existing neurooncologic therapies and address a multitude of therapy‐induced debilitating side effects in patients with brain tumors. Given the limited evidence, the authors conducted a survey to examine the exercise patterns of brain tumor patients across the cancer trajectory.

METHODS

Using a cross‐sectional design, 386 brain tumor patients who received treatment at the Brain Tumor Center at Duke University were sent a questionnaire that assessed self‐reported exercise behavior prior to diagnosis, during adjuvant therapy, and after the completion of therapy.

RESULTS

The response rate was 28% (106 of 383 patients). Descriptive analyses indicated that 42%, 38%, and 41% of participants, respectively, met national exercise prescription guidelines prior to diagnosis, during treatment, and after the completion of adjuvant therapy. Repeated measures analyses indicated no significant changes in the majority of exercise behavior outcomes over the cancer trajectory. However, exploratory analyses indicated that males and younger participants may be at the greatest risk of reducing exercise levels after a brain tumor diagnosis. These analyses remained unchanged after controlling for relevant demographic and medical covariates.

CONCLUSIONS

A relatively high percentage of brain tumor patients are exercising at recommended levels across the cancer trajectory. Moreover, these patients have unique exercise patterns that may be modified by select demographic variables. This preliminary study provides important informative data for future studies examining the potential role of exercise in patients diagnosed with neurologic malignancies. Cancer 2006. © 2006 American Cancer Society.
Adsorption of Functionalized Benzoic Acids on MgSO4⋅H2O (100)
Authors: Maslyuk Volodymyr , Tegenkamp Christoph , Pfnür Herbert , Bredow Thomas
Published: April 2006

Using a combination of ab initio and semiempirical methods, adsorption problems on surfaces with large unit cells and low symmetry can still be studied. Here, a hybrid approach of density functional theory (DFT) and Hartree–Fock (HF) was used. As an example, we determined the geometry and the electronic properties of benzoic acid (BA), salicylic acid (SA) and para‐salicylic acid (p‐SA) adsorbed on MgSO4⋅H2O (100), which are used as conditioner molecules for the electrostatic separation of minerals. Contrary to general expectations, these molecules are chemisorbed, with binding energies around 1.9 eV, forming bonds through the carboxylic O atom of the COOH groups in a nonplanar geometry, although the surface is a stoichiometric wide‐band‐gap insulator and the molecules stay intact. In contrast, a planar adsorption geometry turned out to be nonbonding. Bonding takes place by means of surface–molecule resonances due to the overlap of the valence band with molecular orbitals, assisted by a small charge‐transfer molecule to the surface of around 0.15e. These combined interactions cause an intramolecular twist between the COOH group and the benzene ring.
ESR Spin Probes in Ionic Liquids
Authors: Stoesser Reinhard , Herrmann Werner , Zehl Andrea , Strehmel Veronika , Laschewsky André
Published: April 2006

The spin probes 2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO), 4‐hydroxy‐2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPOL), and 2,2,6,6‐tetramethyl‐4‐trimethylammoniumpiperidine‐1‐oxylIodide (CAT‐1) are examined in a number of ionic liquids based on substituted imidazolium cations and tetrafluoroborate and hexafluorophosphate anions, respectively. The reorientation correlation times τR of the spin probes in these systems have been determined by complete spectra simulation and, for rapid reortientation, by analysis of the intensities of the hyperfine lines of the electron spin resonance (ESR) spectra. A comparison of the results with those from the model system glycerol/water and selected organic solvents is made. Additions of diamagnetic and paramagnetic ions allow the conclusion that salt effects and spin exchange are present, and that both are superimposed by motional effects. Specific interactions in the ionic liquids, as well as between the spin‐probe molecules and the constituents of the ionic liquids are reflected in the spectra of the spin probes, depending on their molecular structure.
Photoexcitation and Relaxation Dynamics of Catecholato–Iron(III) Spin‐Crossover Complexes
Authors: Enachescu Cristian , Hauser Andreas , Girerd Jean‐Jacques , Boillot Marie‐Laure
Published: April 2006

The photophysical properties of the ferric catecholate spin‐crossover compounds [(TPA)Fe(R‐Cat)]X (TPA=tris(2‐pyridylmethyl)amine; X=PF6−, BPh4−; R‐Cat=catecholate dianion substituted by R=NO2, Cl, or H) are investigated in the solid state. The catecholate‐to‐iron(III) charge‐transfer bands are sensitive both to the spin state of the metal ion and the charge‐transfer interactions associated with the different catecholate substituents. Vibronic progressions are identified in the near‐infrared (NIR) absorption of the low‐spin species. Evidence for a low‐temperature photoexcitation process is provided. The relaxation dynamics between 10 and 100 K indicate a pure tunneling process below ≈40 K, and a thermally activated region at higher temperatures. The relaxation rate constants in the tunneling regime at low temperature, kHL(T→0), vary in the range from 0.58 to 8.84 s−1. These values are in qualitative agreement with the inverse energy‐gap law and with structural parameters. A comparison with ferrous spin‐crossover complexes shows that the high‐spin to low‐spin relaxation is generally faster for ferric complexes, owing to the smaller bond length changes for the latter. However, in the present case the corresponding rate constants are smaller than expected based on the single configurational coordinate model. This is attributed to the combined influence of the electronic configuration and the molecular geometry.
Distant regulatory elements in a Sox10‐βGEO BAC transgene are required for expression of Sox10 in the enteric nervous system and other neural crest‐derived tissues
Authors: Deal Karen K. , Cantrell V. Ashley , Chandler Ronald L. , Saunders Thomas L. , Mortlock Douglas P. , Southard‐Smith E. Michelle
Published: April 2006

Sox10 is an essential transcription factor required for development of neural crest‐derived melanocytes, peripheral glia, and enteric ganglia. Multiple transcriptional targets regulated by Sox10 have been identified; however, little is known regarding regulation of Sox10. High sequence conservation surrounding 5′ exons 1 through 3 suggests these regions might contain functional regulatory elements. However, we observed that these Sox10 genomic sequences do not confer appropriate cell‐specific transcription in vitro when linked to a heterologous reporter. To identify elements required for expression of Sox10 in vivo, we modified bacterial artificial chromosomes (BACs) to generate a Sox10βGeoBAC transgene. Our approach leaves endogenous Sox10 loci unaltered, circumventing haploinsufficiency issues that arise from gene targeting. Sox10βGeoBAC expression closely approximates Sox10 expression in vivo, resulting in expression in anterior dorsal neural tube at embryonic day (E) 8.5 and in cranial ganglia, otic vesicle, and developing dorsal root ganglia at E10.5. Characterization of Sox10βGeoBAC expression confirms the presence of essential regulatory regions and additionally identifies previously unreported expression in thyroid parafollicular cells, thymus, salivary, adrenal, and lacrimal glands. Fortuitous deletions in independent Sox10βGeoBAC lines result in loss of transgene expression in peripheral nervous system lineages and coincide with evolutionarily conserved regions. Our analysis indicates that Sox10 expression requires the presence of distant cis‐acting regulatory elements. The Sox10βGeoBAC transgene offers one avenue for specifically testing the role of individual conserved regions in regulation of Sox10 and makes possible analysis of Sox10+ derivatives in the context of normal neural crest development. Developmental Dynamics 235:1413–1432, 2006. © 2006 Wiley‐Liss, Inc.
Morphoregulation of avian beaks: Comparative mapping of growth zone activities and morphological evolution
Authors: Wu Ping , Jiang Ting‐Xin , Shen Jen‐Yee , Widelitz Randall Bruce , Chuong Cheng‐Ming
Published: April 2006

Avian beak diversity is a classic example of morphological evolution. Recently, we showed that localized cell proliferation mediated by bone morphogenetic protein 4 (BMP4) can explain the different shapes of chicken and duck beaks (Wu et al. [2004] Science 305:1465). Here, we compare further growth activities among chicken (conical and slightly curved), duck (straight and long), and cockatiel (highly curved) developing beak primordia. We found differential growth activities among different facial prominences and within one prominence. The duck has a wider frontal nasal mass (FNM), and more sustained fibroblast growth factor 8 activity. The cockatiel has a thicker FNM that grows more vertically and a relatively reduced mandibular prominence. In each prominence the number, size, and position of localized growth zones can vary: it is positioned more rostrally in the duck and more posteriorly in the cockatiel FNM, correlating with beak curvature. BMP4 is enriched in these localized growth zones. When BMP activity is experimentally altered in all prominences, beak size was enlarged or reduced proportionally. When only specific prominences were altered, the prototypic conical shaped chicken beaks were converted into an array of beak shapes mimicking those in nature. These results suggest that the size of beaks can be modulated by the overall activity of the BMP pathway, which mediates the growth. The shape of the beaks can be fine‐tuned by localized BMP activity, which mediates the range, level, and duration of locally enhanced growth. Implications of topobiology vs. molecular blueprint concepts in the Evo–Devo of avian beak forms are discussed. Developmental Dynamics 235:1400–1412, 2006. © 2006 Wiley‐Liss, Inc.
Kinetic and Thermodynamic Aspects of the CT and T‐Shaped Adduct Formation Between 1,3‐Dimethylimidazoline‐2‐thione (or ‐2‐selone) and Halogens
Authors: Aragoni M. Carla , Arca Massimiliano , Devillanova Francesco A. , Grimaldi Patrizio , Isaia Francesco , Lelj Francesco , Lippolis Vito
Published: April 2006

The reactions between L=E donors [L: 1,3‐dimethylimidazolyl framework; E: S (1), Se (2)] and halogens X2(X: Cl, Br, I) to form either “T‐shaped” hypervalent chalcogen (TY) or linear charge‐transfer‐type adducts (CT) have been studied in the density functional theory (DFT) context by considering both thermodynamic and kinetic aspects. Apart from the case of the adducts between sulfur donors and diiodine, hypervalent compounds are calculated to be always more stable than CT ones in the gas phase, in agreement with the experimental results based on spectroscopic and structural determinations. NBO and FMO analyses suggest explanations for this. Reaction mechanism studies reveal that CT adducts are always the first products of the reactions and no transition states connecting the reactants directly to TY adducts have been found. The present calculations indicate that, at least for1and2, TY adducts are obtained from CT adducts and not directly from the reactants.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Carbon and Polymer Filaments in Nanoporous Alumina
Authors: Schneider Jörg J. , Engstler Jörg
Published: April 2006

Nanoporous alumina membranes represent templates for the synthesis and alignment of filamentous nanostructured materials. Porous aluminium oxide (PAOX) membranes are ideal for high‐temperature synthesis. They are transparent, flexible, freestanding and thermally robust. Their pore sizes can be varied over a wide range. The membrane backside seems suited for structuring processes on the nanoscale, for which it may serve as a master. After introducing the formation process of PAOX membranes, synthesis of carbon nanotubes (CNTs) with different morphologies, their electrical field emission properties, and the formation of polymeric filaments and structured polymer surfaces with the aid of PAOX are reported in this microreview.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
A Zig‐Zag [MnII4] Cluster from a Novel Bis(β‐diketonate) Ligand
Authors: Aromí Guillem , Gamez Patrick , Boldron Christophe , Kooijman Huub , Spek Anthony L. , Reedijk Jan
Published: April 2006

A new ligand, H5L3, has been synthesized featuring seven linearly arranged oxygen donors in form of two 1,3‐diketone and three phenol groups. The X‐ray structure of H5L3 unveils a rare case where one of the diketones is in the enolic form and the other one in the bis(carbonyl) form. This structure is shown by 1H NMR to persist in solution. Reaction of H5L3 with Mn(AcO)2 in pyridine leads to the novel tetranuclear cluster [Mn4(H2L3)2(OAc)2(py)5] (1), which displays an unusual core in form of a zig‐zag chain. Bulk magnetic measurements revealed the existence of weak antiferromagnetic coupling within the molecule. Numerical fits to a model described by the Hamiltonian H = –2J1(S1S2 + S3S4) – 2J2(S2S3) yield coupling constants of J1 = –2.23 cm–1, J2 = –0.85 cm–1 and g = 2.08. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
A New Method for the Formation of Anti‐apicophilic (O‐cis) Spirophosphoranes – Kinetic Studies on the Stereomutation of O‐cis Arylspirophosphoranes to Their O‐trans Isomers
Authors: Kajiyama Kazumasa , Yoshimune Miki , Kojima Satoshi , Akiba Kin‐ya
Published: April 2006

P–H spirophosphorane 4 bearing two Martin ligands was converted to dianions (5a–n), bearing R groups, with excess organolithium reagents (RLi). Subsequent oxidation with I2 at ambient temperature gave anti‐apicophilic (O‐cis) spirophosphoranes 2a–n. All anti‐apicophilic phosphoranes 2a–n isomerized irreversibly to the O‐trans spirophosphoranes 3a–n, respectively. For 2,6‐dialkylphenyl derivatives 2k–n, the barrier for pseudorotation between enantiomers 2‐RP and 2‐Sp was rather high, and thus the interconversion could not be observed on the NMR timescale. The activation parameters for the pseudorotation of the triisopropylphenyl (TIP) derivative 2n to 3n were almost identical with those of nBu derivative 2b to 3b, i.e., ΔH‡ = 21.3 kcal mol–1, ΔS‡ = –9.4 eu. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
N′‐(3‐Amino‐1H‐isoindol‐1‐ylidene)‐R‐carbohydrazides and Their Amide‐Type Isomerism
Authors: Hordiyenko Olha V. , Biitseva Angelina V. , Kornilov Mikhail Yu. , Brosse Nicolas , Hocquet Alexandre , Jamart‐Grégoire Brigitte , Shishkin Oleg V. , Zubatyuk Roman I.
Published: April 2006

A series of N′‐(3‐amino‐1H‐isoindol‐1‐ylidene)alkyl(aryl,heteroaryl)carbohydrazides have been synthesized in good yields and their structure and conformational behavior in the solid state and in solution have been studied by X‐ray crystallography, NMR spectroscopy, and quantum calculations. (E)/(Z) amide‐type isomerism and the dependence of the isomeric ratio upon steric effects and solvent polarity are discussed. The thermodynamic parameters of (E) →← (Z) isomerization were determined by 1H NMR dynamic spectroscopy. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
A new quasi‐interpenetrating network formed by poly(N‐acryloyl‐tris‐(hydroxymethyl)aminomethane and polyvinylpyrrolidone: Separation matrix for double‐stranded DNA and single‐stranded DNA fragments by capillary electrophoresis with UV detection
Authors: Wang Qian , Xu Xu , Dai Lixin
Published: April 2006

The preparation of a new separation matrix, quasi‐interpenetrating networks (quasi‐IPNs) formed by poly(N‐acryloyl‐Tris) (poly(tris‐A)) and PVP, and its application for dsDNA and ssDNA fragments separation by CE with UV detection, are presented. This new quasi‐IPN exhibited high sieving performance, good dynamic coating ability, and low viscosity. Single‐base resolutions of dsDNA fragments (Rs = 0.92 for 123/124 bp) and ssDNA fragments (Rs = 0.65 for 123/124 base, Rs = 0.48 for 309/310 base) were achieved by using the quasi‐IPN of poly(tris‐A)/PVP (2% + 2%) solution in a 31 cm effective length linear polyacrylamide (LPA)‐coated column. Single‐base separation of dsDNA fragments (Rs = 0.92 for 123/124 bp) was also obtained within 28 min in a 46.7 cm effective length bare column at higher 160 V/cm electric field strength by using the same quasi‐IPN solution. The RSD of the migration time measured for each DNA fragments was less than 1.5% in the bare column for nine continuous runs. The effects of temperature and electric field strength on the DNA separation were also investigated.
A multiplex assay with 52 single nucleotide polymorphisms for human identification
Authors: Sanchez Juan J. , Phillips Chris , Børsting Claus , Balogh Kinga , Bogus Magdalena , Fondevila Manuel , Harrison Cheryl D. , Musgrave‐Brown Esther , Salas Antonio , Syndercombe‐Court Denise , Schneider Peter M. , Carracedo Angel , Morling Niels
Published: April 2006

A total of 52 SNPs reported to be polymorphic in European, Asian and African populations were selected. Of these, 42 were from the distal regions of each autosome (except chromosome 19). Nearly all selected SNPs were located at least 100 kb distant from known genes and commonly used STRs. We established a highly sensitive and reproducible SNP‐typing method with amplification of all 52 DNA fragments in one PCR reaction followed by detection of the SNPs with two single base extension reactions analysed using CE. The amplicons ranged from 59 to 115 bp in length. Complete SNP profiles were obtained from 500 pg DNA. The 52 loci were efficiently amplified from degraded samples where previously only partial STR profiles had been obtained. A total of 700 individuals from Denmark, Greenland, Somalia, Turkey, China, Germany, Taiwan, Thailand and Japan were typed, and the allele frequencies estimated. All 52 SNPs were polymorphic in the three major population groups. The mean match probability was at least 5.0×10−19 in the populations studied. Typical paternity indices ranged from 336 000 in Asians to 549 000 in Europeans. Details of the 52 SNP loci and population data generated in this work are freely available at http://www.snpforid.org.
Optimization of protein extraction and solubilization for mature grape berry clusters
Authors: Vincent Delphine , Wheatley Matthew D. , Cramer Grant R.
Published: April 2006

Protein extraction from grape berries has been challenging, particularly in mature berries, which can have sugar concentrations as high as 26%. Grape skins and seeds contain large amounts of polyphenols, which can also interfere with efficient protein extraction. In plants, two extraction protocols, TCA/acetone‐based and phenol‐based methods, have been mainly used to extract proteins from different organs or tissues on many species. However, few results have been reported for grape berry clusters. We wanted to determine which of these protocols was optimal for berry clusters in order to achieve both efficient protein extraction and high spot resolution on 2‐D gels. Four protocols, derived from either TCA/acetone or phenol procedures, were tested on mature Cabernet Sauvignon whole berry clusters. The phenol‐based protocols were superior to the TCA/acetone methods, showing larger protein yields and greater spot resolution on 2‐D gels. One method was clearly superior to the rest, a phenol‐based extraction method combined with resuspension in the presence of both urea and thiourea as chaotropes. A total of 81 spots were excised and identified following MALDI‐TOF/TOF MS analyses. Their identification helped further characterize the specificity of each extraction procedure.
A new approach for separating low‐molecular‐weight RNA molecules by staircase electrophoresis in non‐sequencing gels
Authors: Velázquez Encarna , Rivas Raúl , Villar María del , Valverde Angel , Peix Alvaro , Mateos Pedro F. , Velázquez Enrique , Martínez‐Molina Eustoquio
Published: April 2006

Low‐molecular‐weight (LMW) RNA profiles, which include ribosomal and transfer RNA molecules with similar small sizes, are molecular signatures of microorganisms with a great potential in microbial identification. The greatest resolution of these profiles was achieved by staircase electrophoresis in sequencing gels. Nevertheless, this technique is difficult to use because it takes 7 h, the gels have large sizes and it is necessary to heat the system and to recycle the buffer to maintain the denaturing conditions and avoid smile effects. Most available sequencing slabs have no internal temperature control or homogenizing devices, which by contrast are present in some newly designed non‐sequencing slabs. Nevertheless, these slabs present two important problems for separating LMW RNA molecules, the size of gels is only 20 cm (instead of 40 cm) and the maximum voltage that can be reached is only 840 V (instead 2400 V). Staircase electrophoresis follows a model in which the external polarization is incrementally modified with a constant time step value. In the present work, we experimentally confirmed that by reducing the time step and increasing the total number of steps a suitable resolution is achieved. Under these conditions, despite the smaller size of the gels and the lower values of the electric field, the intensity reaches higher values than in sequencing gels and the LMW RNA profiles are correctly separated in 5 h. The resolution of these profiles obtained in non‐sequencing gels is similar to that obtained in sequencing ones facilitating the analysis of large populations of microorganisms in any laboratory.
Electrophoretic mobility and molecular distribution studies of poly(amidoamine) dendrimers of defined charges
Authors: Shi Xiangyang , Bányai István , Rodriguez Keyla , Islam Mohammad T. , Lesniak Wojciech , Balogh Peter , Balogh Lajos P. , Baker James R.
Published: April 2006

Generation 5 ethylenediamine (EDA)‐cored poly(amidoamine) (PAMAM) dendrimers (E5, E denotes the EDA core and 5 the generation number) with different degrees of acetylation and carboxylation were synthesized and used as a model system to investigate the effect of charge and the influence of dendrimer surface modifications on electrophoretic mobility (EM) and molecular distribution. The surface‐modified dendrimers were characterized by size‐exclusion chromatography, 1H NMR, MALDI‐TOF‐MS, PAGE, and CE. The focus of our study was to determine how EM changes as a function of particle charge and molecular mass, and how the molecular distribution changes due to surface modifications. We demonstrate that partially modified dendrimers have much broader migration peaks than those of fully surface functionalized or unmodified E5 dendrimers due to variations in the substitution of individual dendrimer surfaces. EM decreased nonlinearly with increases in surface acetylation for both PAMAM acetamides and PAMAM succinamic acids, indicating a complex migration activity in CE separations that is not solely due to charge/mass ratio changes. These studies provide new insights into dendrimer properties under an electric field, as well as into the characterization of dendrimer‐based materials being developed for medical applications.
Evaluating erosion control measures for biorestoration between the time of soil reinstatement and vegetation establishment
Authors: Hann M. J. , Morgan R. P. C.
Published: April 2006

A modified Universal Soil Loss Equation is used to evaluate the performance of erosion control measures along pipeline rights‐of‐way in Colombia and Georgia in a ten‐year return‐period storm occurring during the first year following pipeline installation. An erosion mat is the most effective way of reducing erosion until a sufficient vegetation cover has been established. On steep slopes and where climate restricts the rate of vegetation growth, it may be necessary to supplement the mat with diverter berms. Although the method cannot be validated in the study areas because of a lack of appropriate data, the results conform to local experience. Copyright © 2006 John Wiley & Sons, Ltd.
Genetic mapping of a putative tumor suppressor locus that influences tumorigenesis and metastasis in mice
Authors: Ayanga Bernard , Price Roger , Gu Xiangjun , Lozano Guillermina , Evans Susan C.
Published: April 2006

The tumor suppressor TP53 is mutated in ∼70% of Li‐Fraumeni syndrome (LFS) families; however, other genes may lead to the predisposition to tumors in other families. We developed a mouse model to search for other tumor suppressors that may be involved in the syndrome. Inbred CE/J mice, which succumb to multiple types of tumors similar to those found in LFS, were crossed with the Trp53‐null 129‐Trp53tm1Tyj mouse. We monitored the tumor onset and type and found a significant earlier tumor onset in the CE/J:129‐Trp53tm1Tyj mice compared with 129‐Trp53tm1Tyj mice with a Trp53‐null allele. Additionally, in CE/J:129‐Trp53tm1Tyj‐Trp53+/− mice, the tumors metastasize, which does not occur in other strains of mice. Using simple‐sequence length polymorphism analysis for loss of heterozygosity in tumors, we identified a putative tumor suppressor locus within 1 cM on mouse chromosome 11, which encompasses 12 mapped genes. © 2006 Wiley‐Liss, Inc.