bluuebunny/crossref_metadata_2025 huggingface dataset:
The iron-regulatory peptide hormone hepcidin: expression and cellular localization in the mammalian kidney
Authors: Kulaksiz H , Theilig F , Bachmann S , Gehrke S G , Rost D , Janetzko A , Cetin Y , Stremmel W
Published: January 2005

It is generally accepted that iron homeostasis is mainly controlled in the gastrointestinal tract by absorption of dietary iron. However, recent studies have shown that the kidneys are also involved in iron metabolism. Since the iron-regulatory and antimicrobial peptide hormone hepcidin was originally isolated from human urine we have investigated the expression as well as the zonal and cellular localization of hepcidin in the mammalian kidney and developed an ELISA assay to analyze hepcidin concentrations in serum and urine. The expression of hepcidin was shown by RT-PCR and immunoblot experiments; its cellular localization was studied by immunocytochemistry in human, mouse and rat kidney, which revealed similar patterns of immunoreactivity. Hepcidin expression was absent from the proximal tubule and descending and ascending thin limbs. There was strong expression in the thick ascending limb of the cortex and in connecting tubules. Moderate expression was noted in the thick ascending limb and collecting ducts of the medulla and in collecting ducts of the papilla. Importantly, the cells of the macula densa were unstained. At the cellular level, hepcidin was localized to the apical cell pole of the renal epithelial cells. Based on its presence in urine, hepcidin may be released apically into the urine. Enhanced levels of hepcidin were determined in patients with chronic renal insuffciency (156.8 ng/ml, controls 104.2 ng/ml) indicating that the kidneys may metabolize and/or eliminate the circulating peptide. From the expression of hepcidin in the mammalian kidney, we have concluded that the iron-regulatory hormone is an intrinsic renal peptide which is not only eliminated by the kidney but is also synthesized in the kidney tubular system. Localization of hepcidin in the kidney implicates an iron-regulatory role of this peptide hormone in the renal tubular system, possibly in connection with the iron transporter divalent metal transporter-1.
Platelet-activating factor acts on cortisol secretion by perfused guinea-pig adrenals via calcium-/phospholipid-dependent mechanisms
Authors: Shimada Toshio , Hirose Taeko , Matsumoto Itsuro , Aikawa Tadaomi
Published: January 2005

Bilateral adrenals of the guinea pig were perfused in situ with an artificial medium equilibrated with 95% O2/5% CO2. Platelet-activating factor (PAF) induced biphasic cortisol responses, which reached a maximum at 10 nM PAF and declined at 100 nM. The effect of the PAF receptor antagonists CV-3988 and CV-6209 on PAF-stimulated cortisol secretion was examined. Prior exposure of adrenal glands to 10 μM CV-3988 or a simultaneous incubation with 10 μM CV-6209 abolished the cortisol response to 10 nM PAF. Lyso-PAF (a PAF precursor and breakdown product) did not affect cortisol secretion. Concentrations of 5–12.5 μM 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7), a protein kinase C (PKC) inhibitor, abolished subsequent cortisol secretion in response to 10 nM PAF. N-[2-(Methylamino)ethyl]-5-isoquinoline sulfonamide dihydrochloride (H-8), a protein kinase A inhibitor, was less effective. A calcium ionophore (A23187) at 3.3 and 10 μM increased cortisol secretion, but the activator of PKC, l-α-1-oleoyl-2-acetyl-sn-3-glycerol (OAG), at 50 μM had no effect. When infused simultaneously, OAG (50 μM) and A23187 (3.3 μM) stimulated cortisol secretion synergistically. The secretory response of cortisol to repeated infusions of adrenocortico-trophin (100 pg/ml) or forskolin (10 μM) was essentially reproducible. By contrast, cortisol secretion in response to repeated infusions of PAF (10 nM) or OAG plus A23187 was not reproducible and the second response was diminished compared with the first. Our findings suggest that PAF plays a role in the regulation of steroidogenesis via a mechanism mediated by the PAF receptor and PKC.
Spectroscopic studies of solid phthalocyanines and their charge transfer salts
Authors: YAKUSHI KYUYA , SIMONYAN MKHITAL , DING YUQIN
Published: January 2005

We present the polarized reflection spectra of several MPcs ( M ≡ Co , Ni , Cu , Zn , Pb ) in the Q-band region and interpret them based on conventional exciton theory. We compare the polarized reflection spectra of the phthalocyanine radical salts NiPc ( AsF 6)0.5, H 2 Pc ( AsF 6)0.67 and LiPc and interpret the new absorption band near the Q-band using the relationship between the degree of oxidation and the intensity of this new band. Based on the pressure dependence of this new band and the diagnostic phonon modes, we prove a pressure-induced charge transfer in NiPc ( AsF 6)0.5. A metal–insulator phase transition is predicted from the analysis of the plasmon absorption and is confirmed by the high-pressure electrical resistivity. We propose the origin of the pressure-induced charge transfer and the mechanism of the metal–insulator transition. We find the optical transition associated with the 3 d z2 band in the reflection spectrum of CoPc ( AsF 6)0.5, which is proved by comparison with the mixed crystals Co x Ni 1 − x Pc ( AsF 6)0.5. A new weak intermolecular optical transition is found through the resonance enhancement of a local phonon in the mixed crystals Co x Ni 1 − x Pc ( AsF 6)0.5.
Discotic liquid crystals of transition metal complexes: 28. Temperature-dependent electronic spectra and X-ray structural analysis of discotic liquid crystalline bis(octakisdodecyloxyphthalocyaninato)lutetium(III) complex
Authors: NAITO RIE , OHTA KAZUCHIKA , SHIRAI HIROFUSA
Published: January 2005

An unidentified mesophase D x of bis(octakisdodecyloxyphthalocyaninato)lutetium(III) reported by us in 1997 was reinvestigated by temperature-dependent X-ray diffraction and temperature-dependent electronic spectra of the thin film. The D x phase was thus established as a novel type of D ro (P21/a) mesophase in which two different stacking distances ht and hf exist. It was also revealed that the step-up increase of electroconductivity is attributable to the step-up enlargement of π-π overlap of Pc macrocycles according to the phase transitions crystal → D ro (P21/a) → D ho . This is strongly related to delocalization of the radical electron.
Z-scan studies and quantum chemical calculations of meso-tetrakis(p-sulfonatophenyl)porphyrin and meso-tetrakis(4-N-methyl-pyridiniumyl)porphyrin and their Fe(III) and Mn(III) complexes
Authors: BORISSEVITCH I. E. , BEZERRA A. G. , GOMES A. S. L. , DE ARAÚJO R. E. , DE ARAÚJO CID B. , OLIVEIRA K. M. T. , TRSIC M.
Published: January 2005

Optical self-defocusing, characterized by the non-linear refractive index n2, was investigated by the Z-scan technique in water solutions of two porphyrins (PPhs), negatively charged meso-tetrakis(p-sulfonatophenyl)porphyrin ( TPPS 4) and positively charged meso-tetrakis(4-N-methyl-pyridiniumyl)porphyrin ( TMPyP ), in their free base forms and as Fe (III) and Mn (III) complexes. Significant n2 values were observed only for the TMPyP metal complexes, while for the other porphyrins the n2 values were negligible. The effect is explained by the reorientation of the porphyrin molecule due to interaction of its permanent dipole moment perpendicular to the molecular ring plane with the electromagnetic field of the exciting light pulse. The permanent dipole moment is due to the shift of the metal atom out of the molecular plane. The electrostatic interaction between the metal atom and charged substituents increases (repulsion) or decreases (attraction) the shift of the metal atom and consequently affects the dipole moment value. Ligand binding to the metal atoms also increases the out-of-plane metal shift and hence the dipole moment and n2 value. pH changes were shown to modify the Fe (III)-ligand structure, thus changing n2. The experimental data correlate well with the metal shift and dipole moment values calculated for simplified PPh structures by the ZINDO method.
Electronic structures and spectral properties of double- and triple-decker phthalocyanine complexes in a localized molecular orbital view
Authors: ISHIKAWA NAOTO
Published: January 2005

This paper reviews the studies on the electronic structures and spectroscopic properties of sandwich-type complexes M ( Pc )2 and M 2( Pc )3. The subjects discussed are as follows. (1) Electronic spectra of closed-shell Pc dimers and trimers. The complexes with closed-shell systems, such as [ Lu ( Pc )2]−, Sn ( Pc )2 and Lu 2( Pc )3, can be thought of as stacked systems composed only of Pc 2−. The excited states of these complexes can be described by locally excited and charge transfer configurations. The coupling terms of the configurations are written using orbitals localized on each Pc ring. Assignments of the observed absorption bands are discussed. Computational studies on the band assignments were carried out using a localized molecular orbital (LO) basis which maximizes orbital populations on one of the Pc rings. (2) Electronic structures of πelectron-deficient Pc dimers and trimers. Oxidation of [ Lu ( Pc )2]− or Lu 2( Pc )3 yields systems with π-electron deficiency or π-hole(s) residing on multiple Pc sites. The delocalized nature of the π-hole in Lu ( Pc )2 is elucidated by comparison of the electronic spectra of symmetric and asymmetric dimers composed of Pc and Nc ( H 2 Nc ≡ naphthalocyanine ). The band assignments of the dimer radicals are discussed. The Pc trimer radical shows an intense absorption band at about 5000 cm−1, which is 2000 cm−1 lower than the valence resonance band of Lu ( Pc )2. The two-electron-deficient complexes [ Lu ( Pc )2]+ and [ Lu 2( Pc )3]2+ also show intense near-IR bands at higher energy than the corresponding monoradical species. The interactions that determine the excitation energies of the near-IR bands of the π-electron-deficient species are elucidated.
Eyewitness memory for a simulated misdemeanor crime: the role of age and temperament in suggestibility
Authors: Shapiro Lauren R. , Blackford Cheryl , Chen Chiung‐Fen
Published: January 2005

The timing of misleading questions within an interview (immediate, 7‐week delay) and temperament characteristics as correlates of suggestibility were examined in two experiments. In Experiment 1, 6/7‐year‐olds, 9/10‐year‐olds, and adults were given general‐to‐specific questions at both intervals or misleading questions initially and general‐to‐specific questions at delay. In Experiment 2, 4/5‐year‐olds, 9/10‐year‐olds, and adults were given general‐to‐specific questions at both intervals or general‐to‐specific questions initially and misleading questions at delay. Introducing misleading questions in the initial interview increased suggestibility for peripheral features, whereas suggestibility for central features was found when misleading questions were asked in the delayed interview. Age changes in recall and elaboration for categorical information were found. Some temperament characteristics were associated with age‐related changes in compliance and suggestibility. Copyright © 2005 John Wiley & Sons, Ltd.
Interstitial deletion 8q11.2‐q13 with congenital anomalies of CHARGE association
Authors: Arrington Cammon B. , Cowley Brett C. , Nightingale Daniel R. , Zhou Holly , Brothman Arthur R. , Viskochil David H.
Published: January 2005

Specific genetic loci responsible for CHARGE association are currently unknown. Herein, we describe a neonate with clinical manifestations consistent with CHARGE association who has a de novo interstitial deletion involving bands 8q11.2 to 8q13. Genetic mapping and genomic microarray technology have been used to more accurately define the breakpoints of this deletion. Within the deleted region, there are approximately 150 expressed genes, one or more of which may contribute to the manifestations of CHARGE association. © 2005 Wiley‐Liss, Inc.
Effects of physostigmine on the pharmacokinetics of intravenous parathion in rats
Authors: Hurh Eunju , Lee Eun J. , Kim Yoon G. , Kim Sung Y. , Kim So H. , Kim Young C. , Lee Myung G.
Published: January 2005

It was reported that the area under the plasma concentration‐time curve from time zero to time infinity (AUC) of parathion was significantly smaller, and the time‐averaged total body clearance (Cl) of parathion was significantly faster after intravenous administration of parathion to rats pretreated with dexamethasone than those in control rats. This was supported by significantly faster intrinsic clearance of parathion to form paraoxon in hepatic microsomal fraction of rats pretreated with dexamethasone. The above data suggested that parathion was metabolized to paraoxon by dexamethasone‐inducible hepatic cytochrome P450 (CYP) 3A in rats. The purpose of this study is to explain the protective effects of physostigmine against paraoxon toxicity by suppressing CYP3A, and hence, decreasing formation of a toxic metabolite, paraoxon. The pharmacokinetic changes of parathion and paraoxon were investigated after intravenous administration of parathion, 3 mg/kg, to control Sprague–Dawley rats, and the rats pretreated with physostigmine (100 µg/kg, intraperitoneal injection 30 min before parathion administration). After a 1‐min intravenous infusion of parathion to rats pretreated with physostigmine, the AUC of parathion (60.4 compared with 73.7 µg min/mL) was significantly greater, Cl of parathion (49.7 compared with 40.7 mL/min/kg) was significantly slower, and amount of paraoxon recovered from liver, mesentery and large intestine at 5 min was smaller than those in control rats. Based on in vitro rat hepatic microsomal studies, physostigmine inhibited significantly the erythromycin N‐demethylase activity (1.03 compared with 0.924 nmol/mg protein/min), mainly mediated by hepatic cytochrome P450 3A in rats. The above data suggested that the formation of paraoxon was inhibited in rats pretreated with physostigmine by inhibiting CYP3A. Copyright © 2000 John Wiley & Sons, Ltd.
Influence of dose on the distribution kinetics of ciprofloxacin and ofloxacin in the isolated hindlimb of the rat
Authors: Casquero‐Dorado A.C. , Colino C.I. , Martínez M.S , Sánchez‐Navarro A.
Published: January 2005

The aim of this study was to determine whether the dose influences the distribution kinetics of ciprofloxacin and ofloxacin in muscle‐ bone‐ and skin‐tissues included in the isolated hindlimb of the rat. Experiments were carried out in the isolated perfused hindlimb of the rat, administering a single dose of 45, 450 or 900 µg of each quinolone as a bolus injection. Outflow perfusate samples were collected for 20 min and drug levels were determined by an HPLC technique. The mean transit time (MTT) and the distribution volume of ciprofloxacin significantly increased with the dose injected (MTT=1.47±0.69, 8.74±0.27 and 9.52±2.95 min for 45, 450 and 900 µg, respectively). A similar situation was observed with ofloxacin, although the increase in these parameters was less pronounced (MTT=3.65±0.86, 7.92±2.03 and 8.32±1.70 min for 45, 450 and 900 µg, respectively). The distribution of ciprofloxacin and ofloxacin in the rat hindlimb appears to be a dose‐dependent process, at least for the dose range considered in this study. This might explain the high variability in the distribution coefficients reported for these drugs in literature. Copyright © 2000 John Wiley & Sons, Ltd.
Urinary excretion of valproate metabolites in children and adolescents
Authors: Reith David M. , Andrews Jaymie , Parker‐Scott Suzie , Eadie Mervyn J.
Published: January 2005

The objective of this communication is to describe the changes in the metabolic profile of valproic acid (VPA) from early to late childhood and adolescence. A cross‐sectional study of 12 children and adolescents attending a neurological outpatients department, who were medicated with VPA, was carried out. The proportions of daily dose excreted as VPA‐glucuronide, 3‐oxo‐VPA and 4‐OH‐VPA were calculated by relating 24‐h recovery of these metabolites from urine to daily VPA dose. VPA, 3‐oxo‐VPA and 2‐en‐valproic acid (2‐en‐VPA) were measured in trough serum samples. VPA and its metabolites were measured using a capillary gas chromatograpy method. The proportion of daily dose recovered as VPA‐glucuronide in children 10 years and younger was smaller than in older children (p<0.05). There were no differences between age groups in the recovery of the other measured metabolites. Lamotrigine (LTG) comedication was also associated with a higher proportion of VPA dose recovered as glucuronide (p<0.01). LTG comedication had a stronger association with a higher proportion of dose being recovered as VPA‐glucuronide on multivariate analysis than did the age group (p=0.001 versus p<0.05). In conclusion, older children and adolescents, when compared with younger children, and those comedicated with LTG excrete a higher proportion of VPA dose as VPA‐glucuronide. Copyright © 2000 John Wiley & Sons, Ltd.
Application of in vitro–in vivo correlations (IVIVC) in setting formulation release specifications
Authors: Modi Nishit B. , Lam Andrew , Lindemulder Elizabeth , Wang Bei , Gupta Suneel K.
Published: January 2005

An in vitro–in vivo correlation (IVIVC) was established for an osmotic controlled‐release dosage form by deconvolution using data from an immediate‐release treatment as the characteristic response. The established IVIVC was evaluated internally (predicting data used to develop the IVIVC) and externally (predicting data not originally included in developing the IVIVC), and the application of the IVIVC in product development was demonstrated. The estimated in vivo dissolution profile compared favorably with the in vitro drug release profile. Good agreement was demonstrated between the estimated and observed cumulative drug release across the entire time course (level A correlation) with low (<10%) predictive error for both Cmax and AUC∞. External validation using lots not initially included in the model development compared very well with the observed in vivo profile, with mean prediction errors less than 10% for both Cmax and AUC∞. The proposed method demonstrates a schema for developing IVIVCs using data from biostudies routinely conducted during formulation development. The method should facilitate product optimization and can support setting in vitro dissolution specification. Copyright © 2000 John Wiley & Sons, Ltd.
The effect of fluency training on math and reading skills in neuropsychiatric diagnosis children: a multiple baseline design
Authors: Hartnedy Stephanie L. , Mozzoni Michael P. , Fahoum Yousef
Published: January 2005

Fluency (fast and accurate responding) has been found to facilitate the retention, maintenance, endurance, and application of learned skills. Fluency training has been employed effectively in academic, vocational, industrial, and rehabilitative settings. Using a multiple baseline design, this study expanded previous applications by targeting academic deficits of children with neurological and psychiatric diagnoses in a residential treatment facility. Total response rates were measured in 60 second timed probes. Academic tool skills increased and error rates decreased for all participants after implementation of fluency training. Implications for improving attention to task and targeting minimum competency skills are discussed, as is determining the role that practice plays in increasing fluency rate. Copyright © 2005 John Wiley & Sons, Ltd.
Using behavioral interventions to treat speech disorders in persons with head trauma
Authors: Wesolowski Michael D. , Zencius Arnie H. , McCarthy‐Lydon Diane , Lydon Steve
Published: January 2005

Two men with head injuries resulting in speech disorders were treated by asking them orientation questions and prompting answers using either least to most prompting or flashcards. For one participant, the orientation questions were about objects, places, and foods. The other man's questions were about objects, places, people, and time. The results demonstrated that both men were able to respond correctly to the orientation questions in fewer than 30 trials. Copyright © 2005 John Wiley & Sons, Ltd.
Antecedent assessment and intervention to reduce physical restraint (protective holding) of children and adolescents with acquired brain injury
Authors: Luiselli James K. , Dunn Erin K. , Pace Gary M.
Published: January 2005

This research concerned antecedent assessment and intervention to reduce physical restraint (protective holding) of children and adolescents with acquired brain injury and serious challenging behaviors (aggression, self‐injury, property destruction). Study I was an assessment of antecedent conditions associated with protective holding among 15 students attending a community‐based residential school. Conceived as a descriptive assessment, we identified several environmental influences that set the occasion for protective holding. Study II describes how information gathered from antecedent assessment was used to formulate an intervention that reduced frequency of protective holding with one student. Clinical implications are discussed. Copyright © 2005 John Wiley & Sons, Ltd.
Coexpression in yeast ofTaxuscytochrome P450 reductase with cytochrome P450 oxygenases involved in Taxol biosynthesis
Authors: Jennewein Stefan , Park Hangil , DeJong JingHong M. , Long Robert M. , Bollon Arthur P. , Croteau Rodney B.
Published: January 2005

To maximize redox coupling efficiency with recombinant cytochrome P450 hydroxylases from yew (Taxus) species installed in yeast for the production of the anticancer drug Taxol, a cDNA encoding NADPH:cytochrome P450 reductase fromT. cuspidatawas isolated. This single‐copy gene (2,154 bp encoding a protein of 717 amino acids) resembles more closely other reductases from gymnosperms (∼90% similarity) than those from angiosperms (<80% similarity). The recombinant reductase was characterized and compared to other reductases by heterologous expression in insect cells and was shown to support reconstituted taxoid 10β‐hydroxylase activity with an efficiency comparable to that of other plant‐derived reductases. Coexpression in yeast of the reductase along withT. cuspidatataxoid 10β‐hydroxylase, which catalyzes an early step of taxoid biosynthesis, demonstrated significant enhancement of hydroxylase activity compared to that supported by the endogenous yeast reductase alone. Functional transgenic coupling of theTaxusreductase with a homologous cytochrome P450 taxoid hydroxylase represents an important initial step in reconstructing Taxol biosynthesis in a microbial host. © 2005 Wiley Periodicals, Inc.
High‐throughput measurement of protein stability in microtiter plates
Authors: Aucamp Jean P. , Cosme Ana M. , Lye Gary J. , Dalby Paul A.
Published: January 2005

The direct determination of protein stability at high throughput has applications in proteomics, directed evolution, and formulation. Each application places different requirements on the accuracy of stability or transition midpoint determination. The measurement of protein stability by chemical denaturation has been previously performed at medium throughput and high accuracy using autotitrating fluorometers, after removal of proteins from the 96‐well plate format in which they were expressed and purified. Herein we present a higher‐throughput method for measuring and indexing the stability of proteins maintained within the 96‐well format using a fluorescence microplate reader. Protein unfolding transitions were monitored by tryptophan fluorescence at 340 nm and assessed using bovine and equine cytochrome c (cyt c), as well as bovine serum albumin (BSA) stabilized with various amounts of palmitic acid. Two different approaches for generating unfolding curves in microtiter plates have been evaluated for their accuracy and applicability. Unfolding curves generated by the serial addition of denaturant into single wells allowed high‐throughput stability screens capable of identifying protein variants with unfolding midpoint differences of 0.15 M denaturant concentration or larger. Such a method would be suitable for screening large numbers of proteins, as typically generated for directed evolution. Unfolding curves generated using one well per denaturant concentration allowed for medium‐throughput stability screening and generated more accurate and precise stability values (C1/2 ± 0.05 M, mG, and ΔG) for cyt c that are similar to values reported in literature. This method is suitable for screening the smaller numbers of proteins generated in proteomic research programmes. By using BSA stabilized with various palmitate concentrations and simple numerical indexing, it was shown that both experimental methods can successfully rank the order of protein stability. © 2005 Wiley Periodicals, Inc.
Sex-based analysis of the outcome of laparoscopic cholecystectomy for acute cholecystitis
Authors: Lee H K , Han H-S , Min S K , Lee J-H
Published: January 2005

Background

Complicated acute cholecystitis, for example when empyema or gangrene is present, is associated with increased postoperative morbidity and mortality rates. The aim of this study was to determine the correlation between sex, the severity of acute cholecystitis and the outcome of laparoscopic cholecystectomy.

Methods

Of 674 patients in whom laparoscopic cholecystectomy was attempted, 348 had chronic cholecystitis and 326 had acute cholecystitis. The medical records of the latter were reviewed retrospectively.

Results

The proportion of male patients significantly increased with the severity of cholecystitis: 37·4 per cent of those with chronic cholecystitis were men, compared with 44·4 per cent of those with uncomplicated acute cholecystitis and 57 per cent of those with complicated acute cholecystitis (P = 0·001). Multivariate analysis showed that advanced age (odds ratio 2·24; P = 0·004) and male sex (odds ratio 1·76; P = 0·029) independently predicted complicated acute cholecystitis. The conversion rate to open operation was 6·4 per cent in men and 5·9 per cent in women (P = 0·843). The postoperative complication rate was 10·3 and 8·2 per cent respectively (P = 0·528).

Conclusion

Male sex was identified as a risk factor for more severe acute cholecystitis, but outcome for men after laparoscopic cholecystectomy was not significantly different from that for women.
Towards a Better Understanding of Magnetic Interactions within m‐Phenylene α‐Nitronyl Nitroxide and Imino Nitroxide Based Radicals, Part III: Magnetic Exchange in a Series of Triradicals and Tetraradicals Based on the Phenyl Acetylene and Biphenyl Coupling Units
Authors: Catala Laure , Le Moigne Jacques , Gruber Nathalie , Novoa Juan J. , Rabu Pierre , Belorizky Elie , Turek Philippe
Published: January 2005

The present work completes and extends our previous reports1, 2 on the determination of the magnetic ground state and on the strength of the through bond exchange coupling within series of biradicals. This knowledge was subsequently exploited for the analysis of the magnetic interactions in their crystals. We report here the studies of series of triradicals incorporating α‐nitronyl nitroxides (NN) or α‐imino nitroxides (IN) as terminal radical fragments connected through a m‐phenylene coupling unit in one case and a phenyl acetylene unit in other case. Tetraradical derivatives have also been studied. The studies of isolated molecules (EPR in solution and DFT calculations) allow the assessment of the magnetic interactions through the magnetic coupling unit. All triradical derivatives are found to exhibit a quartet ground state, whereas a singlet ground state is determined for the tetraradical. This last result reinforces previous findings that the singlet ground state is favoured in related biradicals involving similar m‐phenylene couplers. Moreover, the through bond magnetic exchange coupling for the ortho–meta connectivity could be demonstrated as being ferromagnetic, thus ascertaining our previous hypotheses.1 The magnetic properties of the triradicals and tetraradicals in their solid state have been rationalized by using a previously proposed methodology,2 allowing to identify the most relevant magnetic pathways.
Zirconocene‐Mediated Intermolecular Coupling of Si‐tethered Diynes with Alkynes, Ketones, Aldehydes, and Isocyanates by means of Novel Skeletal Rearrangement of Zirconacyclobutene–Silacyclobutene and Zirconacyclohexadiene–Silacyclobutene Fused‐Ring Intermediates
Authors: Yu Tao , Sun Xiaohua , Wang Congyang , Deng Liang , Xi Zhenfeng
Published: January 2005

Bis(alkynyl)silanes react with low valent zirconocene species to afford zirconacyclobutene intermediates. These in situ generated reactive organometallic intermediates can react with alkynes, ketones, aldehydes, and isocyanates by means of a novel skeletal rearrangement. When a zirconacyclobutene intermediate was treated with an alkyne, an α‐alkynylsilyl zirconacyclopentadiene was formed. Addition of dimethyl acetylenedicarboxylate (DMAD) and CuCl resulted in one‐pot formation of an alkynylsilyl–benzene derivative from three different alkynes. At a higher temperature, the α‐alkynylsilylzirconacyclopentadiene was transformed by means of an intramolecular skeletal rearrangement to a zirconacyclohexadiene–silacyclobutene fused‐ring compound, which reacted with DMAD in the presence of CuCl affording the same alkynylsilyl–benzene derivative. When treated with a ketone, an aldehdye, or an isocyanate, the zirconocyclobutene intermediate also underwent the above‐mentioned skeletal rearrangement, generating zirconocene‐mediated cross‐coupling products.
Diaminocarbene‐ and Fischer‐Carbene Complexes of Palladium and Nickel by Oxidative Insertion: Preparation, Structure, and Catalytic Activity
Authors: Kremzow Doris , Seidel Günter , Lehmann Christian W. , Fürstner Alois
Published: January 2005

Oxidative insertion of [Pd(PPh3)4] or [Ni(cod)2]/PPh3into the CCl bond of various 2‐chloroimidazolinium‐ and other ‐amidinium salts affords metal–diaminocarbene complexes in good to excellent yields. This procedure is complementary to existing methodology in which the central metal does not change its oxidation state, and therefore allows to incorporate carbene fragments that are difficult to access otherwise. The preparation of a variety of achiral as well as enantiomerically pure, chiral metal–NHC complexes (NHC = N‐heterocyclic carbene) and metal complexes with acyclic diaminocarbene ligands illustrates this aspect. Furthermore it is shown that oxidative insertion also paves a way to prototype Fischer carbenes of PdII. Since the required starting materials are readily available from urea‐ or thiourea derivatives, this novel approach allows for substantial structural variations of the ligand backbone. The catalytic performance of the resulting library of nickel‐ and palladium–carbene complexes has been evaluated by applications to prototype Suzuki‐, Heck‐, and Kumada–Corriu cross‐coupling reactions as well as Buchwald–Hartwig aminations. It was found that even Fischer carbenes show appreciable catalytic activity. Moreover, representative examples of all types of neutral and cationic metal–carbene complexes formed in this study have been characterized by X‐ray crystallography.
Synthesis and Characterization of Tetranuclear Alkyltin(IV) Compounds with Schiff Base Ligand Pyruvic Acid Isonicotinyl Hydrazone and Crystal Structure of {[nBu2Sn(C9H8N3O3)O]SnBun}2
Authors: Yin Han‐Dong , HONG Min , Wang Qi‐Bao
Published: January 2005

The tetranuclear alkyltin(IV) compounds {[R2Sn(C9H8N3O3)O]SnR3}2[R=n‐Bu (1), 4‐CNC6H4CH2(2), C6H5CH2(3), 4‐ClC6H4CH2(4)] were prepared by the reaction of Schiff base ligand pyruvic acid isonicotinyl hydrazone with (R3Sn)2O in the corresponding molar ratio of 1:1. All compounds have been characterized by elemental analysis, IR and1H NMR spectra. The crystal structure of compound1was determined by X‐ray single crystal diffractional analysis. This compound exhibits a dimeric structure containing distannoxane units with two types of the tin atoms. For the first tin atom, it appears to be seven‐coordinated with a distorted pentagonal bipyramid geometry, and the other is five‐coordinated with a distorted trigonal bipyramidal geometry. The molecules are packed in the unit cell in two‐dimensional network structure through an interaction between the N atoms of the pyridine and the tin atoms of an adjacent molecule.
Dumbbell‐shaped Carbosilane Dendrimers Based on 1,6‐Hexanediol
Authors: Tang Xin‐De , Zhang Qi‐Zhen , Li Ai‐Xiang , Fan Xing‐He , Chen Xiao‐Fang , Zhou Qi‐Feng
Published: January 2005

Novel carbosilane dendrimers based on 1,6‐hexanediol were prepared by divergent approach. Using 1,6‐hexanediol‐based diallyl ether as the core molecule, the dendrimers were prepared to the third generation with 54 allyl groups on the periphery by alternate hydrosilylation‐allylation reactions.
Crystal Structure of Bis{1‐methylthio‐1‐[1‐phenyl‐1‐(1‐phenyl‐3‐methyl‐5‐oxo‐4,5‐dihydropyrazol‐4‐ylene)‐methylamino]‐iminomethyl} Disulfide with the “U” Conformation
Authors: Liu Lang , Ji Ya‐Li , Jia Dian‐Zeng , Liu Guang‐Fei , Yu Kai‐Bei
Published: January 2005

The reaction of 1‐phenyl‐3‐methyl‐4‐benzoyl‐2,5‐dihydro‐1H‐pyrazol‐5‐one (PMBP) and methyldithiocarbazate (mdtc) in methanol results in formation of a yellow crystalline solid, adduct of 1‐phenyl‐3‐methyl‐4‐benzoyl‐2,5‐dihydro‐1H‐pyrazol‐5‐one and methyldithiocarbazate. When the yellow solids were dissolved in a mixture of methanol and ether (1:4), a red crystal, which is an oxidation product of the former, was obtained by allowing solvent to evaporate for a few days at room temperature. The X‐ray analysis of the red crystal indicates that it is a novel disulfide with a special structure like a “U” conformation in the solid state.
Enantioselective Dihydroxylation of Alkenes Catalyzed by a PEG‐Bound Bi‐Cinchona Alkaloid Ligand
Authors: Yang Xi‐Wen , Liu Han‐Quan , Xu Ming‐Hua , Lin Guo‐Qiang
Published: January 2005

The recyclable PEG‐bound bi‐cinchona alkaloid ligand has been successfully applied to the homogeneous catalytic asymmetric dihydroxylation of various alkenes; good yields and excellent enantioselectivities were obtained. The ligand could be easily recovered and reused for 10 times without any apparent loss of its catalyst efficiency.
Feature‐oriented programming: A new way of object composition
Authors: Prehofer Christian
Published: January 2005

We propose a new model for flexible composition of objects from a set of features. Features are services of an object and are similar to classes in object‐oriented languages. In many cases, features have to be adapted in the presence of other features, which is also called the feature interaction problem. We introduce explicit interaction handlers which can adapt features to other features by overriding methods. When features are composed, the appropriate interaction handling is added in a way which generalizes inheritance and aggregation. For a set of features, an exponential number of different feature combinations is possible, based on a quadratic number of interaction resolutions. We present the feature model as an extension of Java and give two translations to Java, one via inheritance and the other via aggregation. We show that the feature model interacts nicely with several common language extensions such as type parameters, exceptions, and higher‐order functions. Copyright © 2001 John Wiley & Sons, Ltd.
Mutator phenotype in cancer: Timing and perspectives
Authors: Bielas Jason H. , Loeb Lawrence A.
Published: January 2005

Normal human cells replicate their DNA with exceptional accuracy. During every division cycle, each daughter cell receives a full and accurate complement of genetic information. It has been estimated that approximately one error occurs during DNA replication for each 109 to 1010 nucleotides polymerized. Stem cells, the cells that are progenitors of cancer, may replicate their genes even more accurately. In contrast, the malignant cells that constitute a tumor are markedly heterogeneous and exhibit multiple chromosomal abnormalities and alterations in the nucleotide sequence of DNA. To account for the disparity between the rarity of mutations in normal cells and the large numbers of mutations present in cancer, we initially hypothesized that during tumor progression, cancer cells must exhibit a mutator phenotype. In this perspective, we summarize the evidence supporting a mutator phenotype in human cancer, analyze recent measurements of mutations in human cancer, consider the timing for the expression of a mutator phenotype, and focus on the important consequences of large numbers of random mutations in human tumors. Environ. Mol. Mutagen., 2005. © 2005 Wiley‐Liss, Inc.
Modified median polish kriging and its application to the Wolfcamp–Aquifer data
Authors: Berke Olaf
Published: January 2005

In geostatistics, spatial data will be analyzed that often come from irregularly distributed sampling locations. Interest is in modelling the data, i.e. estimating distributional parameters, and then to predict the phenomenon under study at unobserved sites within the corresponding sampling domain. The method of universal kriging for spatial prediction was introduced to cover the problem of spatial trend effects. This is done by incorporating linear trend models, e.g. polynomial functions of the spatial co‐ordinates. However, universal kriging is sensitive to additive outliers. An outlier resistant method for spatial prediction is median polish kriging. Both methods have certain advantages but also some drawbacks. Here, universal kriging and median polish kriging will be combined to the robust spatial prediction method called modified median polish kriging. An example illustrates the method of modified median polish kriging along with piezometric‐head data from the Wolfcamp–Aquifer. Copyright © 2001 John Wiley & Sons, Ltd.
Char Formation in Flame‐Retarded Fibre–Intumescent Combinations. Part V. Exploring Different Fibre/Intumescent Combinations
Authors: Kandola Baljinder K. , Richard Horrocks A. , Horrocks Samuel
Published: January 2005

Previous research work in our laboratory has indicated that the efficiency of certain flame‐retardant fibres can be further enhanced if certain interactive intumescents are dispersed on their surfaces. In our previously reported work we have successfully observed interactions between certain commercially available flame‐retardant cellulosic and regenerated cellulose (viscose) fibres and two melamine and phosphoric acid‐based intumescent systems. In the present work we have explored the use of other intumescent systems—melamine cyanurate, melamine borate, melamine oxalate, melamine pyrophosphate and an inorganic silicate‐based intumescent, Cylatherm. Two non‐cellulosic fibres—the novoloid (Kynol) and melamine‐formaldehyde (Basofil) were also explored in combination with different intumescent systems. These systems were studied by thermal analytical techniques to observe any possible interaction between FR fibre and intumescent components. Of these intumescents, only melamine borate and melamine pyrophosphate showed interactions with flame retardant cellulosic fibres and both Kynol and Basofil indicated char interactive tendencies with some of the phosphorus‐containing intumescents. Copyright © 2002 John Wiley & Sons, Ltd.
Mathematical modelling of fire development in cable installations
Authors: Hees P. Van , Axelsson J. , Green A. M. , Grayson S. J.
Published: January 2005

In 1996 DG XII of the European Commission (Research and Development) approved a 3 year project on the fire performance of electrical cables. Within this FIPEC project, a major part of the work involved correlation and mathematical modelling of flame spread and heat release rate in cable installations. The FIPEC project has developed different levels of testing ranging from a small‐scale, cone calorimeter test procedures developed for cables and materials, a full‐scale‐test procedure based on the IEC 60332‐3, but utilizing HRR and SPR measurements, and a real scale test conducted on model cable installations. Links through statistical correlations and mathematical fire modelling between these levels were investigated and the findings are presented in this paper. These links could form the scientific foundations for standards upon which fire performance measurements can be based and for new fire engineering techniques within fire performance based codes. Between each testing level correlation, numerical and mathematical models were performed. All of the models were based on the cone calorimeter test method. The complexity of the models varied from correlation models to advanced physical pyrolysis models which can be used in CFD codes. The results will allow advanced prediction of cable fires in the future. Also a bench mark was established for the prediction of cable performance by means of data obtained from the constituent materials. Copyright © 2002 John Wiley & Sons, Ltd.
The southern Menderes Massif (western Turkey): geochronology and exhumation history
Authors: Bozkurt Erdi̇n , Satir Muharrem
Published: January 2005

In the southern flank of the Menderes Massif, western Turkey, an E–W‐trending quartz–mica vein was recognized in the augen gneisses of the so‐called ‘core’ series. Rb‐Sr determinations of two undeformed or slightly deformed mica books from the vein yielded Palaeocene–Early Eocene ages (c. 62–43 Ma) for the vein formation. The new data are interpreted to closely post‐date the time of major Barrovian‐type High Temperature/Medium Pressure (HT/MP) main Menderes metamorphism (MMM) and coeval crustal‐scale top‐to‐the‐N‐NNE Tertiary deformation that affected the whole Massif. Subsequent cooling occurred in the Middle Eocene (36 ± 2 Ma Ar‐Ar mica ages).

Top‐to‐the‐N‐NNE structures were later overprinted by top‐to‐the‐S‐SSW fabrics within normal‐sense ductile shear zone, located between the core augen gneisses in the footwall and the structurally overlying cover schists in the hanging wall. The Massif was at the surface by the Early Miocene. Field relations clearly demonstrate that the age of top‐to‐the‐S‐SSW deformation is well constrained between the age of the MMM and the Early Miocene, and that exhumation was mainly tectonically controlled. Copyright © 2000 John Wiley & Sons, Ltd.
Straightforward furrow irrigation can be 70% efficient
Authors: Jurriëns M. , Lenselink K.J.
Published: January 2005

Design and operation of furrow irrigation often focus on finding an optimum combination of the length, the flow rate, and the cut‐off time. In this paper, we analyse various combinations of these three variables using the Furdev program. To express the hydraulic performance of furrow irrigation, we use the standard application efficiency, the surface run‐off ratio, and the deep percolation ratio. The paper investigates three cases: first, we discuss the optimum flow rate for a given length, then the optimum length for a given flow rate, and, finally, we establish a relationship between flow rate and length. In the analyses, wide ranges of soils, lengths, and flow rates are covered.

We conclude that it is nearly always possible to find a combination of the three major design variables that will yield an application efficiency of 69–73%, or, say, 70%. Under the assumed conditions of constant inflow, open‐ended furrows, and no under‐irrigation, a higher efficiency is never possible and a lower one not desirable. The 70% ‘rule’ is true only if one of the three variables can be chosen freely. Operational practices like cut‐back, reuse, or blocking the end of the furrow, could easily lead to efficiencies higher than 70%. Copyright © 2001 John Wiley & Sons, Ltd.
FGF6 regulates muscle differentiation through a calcineurin‐dependent pathway in regenerating soleus of adult mice
Authors: Armand Anne‐Sophie , Pariset Claude , Laziz Iman , Launay Thierry , Fiore Frédéric , Della Gaspera Bruno , Birnbaum Daniel , Charbonnier Frédéric , Chanoine Christophe
Published: January 2005

Important functions in myogenesis have been proposed for FGF6, a member of the fibroblast growth factor family accumulating almost exclusively in the myogenic lineage, but its precise role in vivo remains mostly unclear. Here, using FGF6 (−/−) mice and rescue experiments by injection of recombinant FGF6, we dissected the functional role of FGF6 during in vivo myogenesis. We found that the appearance of myotubes was accelerated during regeneration of the soleus of FGF6 (−/−) mice versus wild type mice. This accelerated differentiation was correlated with increased expression of differentiation markers such as CdkIs and calcineurin, as well as structural markers such as MHCI and slow TnI. We showed that an elevated transcript level for calcineurin Aα subunit correlated with a positive regulation of calcineurin A activity in regenerating soleus of the FGF6 (−/−) mice. Cyclin D1 and calcineurin were up‐ and down‐regulated, respectively in a dose‐dependent manner upon injection of rhFGF6 in regenerating soleus of the mutant mice. We showed an increase of the number of slow oxidative (type I) myofibers, whereas fast oxidative (type IIa) myofibers were decreased in number in regenerating soleus of FGF6 (−/−) mice versus that of wild type mice. In adult soleus, the number of type I myofibers was also higher in FGF6 (−/−) mice than in wild type mice. Taken together these results evidenced a specific phenotype for soleus of the FGF6 (−/−) mice and led us to propose a model accounting for a specific dose‐dependent effect of FGF6 in muscle regeneration. At high doses, FGF6 stimulates the proliferation of the myogenic stem cells, whereas at lower doses it regulates both muscle differentiation and muscle phenotype via a calcineurin‐signaling pathway. © 2005 Wiley‐Liss, Inc.
Multi‐parameter investigation of tandem mass spectrometry in a linear ion trap using response surface modelling
Authors: Moberg My , Markides Karin E. , Bylund Dan
Published: January 2005

The feasibility of experimental design in combination with subsequent response surface modelling was illustrated for the prediction and interpretation of tandem mass spectrometric (MS/MS) fragmentation data using a linear quadrupole ion trap under various experimental conditions. The instrumental parameters included were (i) the pressure of the collision gas, (ii) the collision energy, (iii) the fill time of the linear ion trap and (iv) the scan rate. The spectral intensity and width of five fragment ions of the doubly charged neuro‐active peptide bombesin were used for evaluation, and all experiments were performed so as to resemble the results obtained from a liquid chromatographic peak. The reported results show how fairly simple mathematical tools can be utilized successfully to describe fundamental mechanisms associated with multiple collisional activation and collision‐induced dissociation processes without an extensively controlled experimental environment. Most beneficial, using the suggested approach, is the ability to study interaction (synergistic) effects between various parameters. As was realized from the results, many interaction effects are indeed significant. For example, the effect on the signal intensity of different collision gas pressure settings is strongly dependent on the settings of the other parameters. The described approach can easily be adopted for optimization purposes of any MS/MS experiment. Copyright © 2005 John Wiley & Sons, Ltd.