bluuebunny/crossref_metadata_2025 huggingface dataset:
Ambipolar Charge Transport in Air‐Stable Polymer Blend Thin‐Film Transistors
Authors: Babel A. , Wind J. D. , Jenekhe S. A.
Published: September 2004

Ambipolar thin‐film transistors based on a series of air‐stable, solution‐processed blends of an n‐type polymer poly(benzobisimidazobenzophenanthroline) (BBL) and a p‐type small molecule, copper phthalocyanine (CuPc) are demonstrated, where all fabrication and measurements are performed under ambient conditions. The hole mobilities are in the range of 6.0 × 10–6 to 2.0 × 10–4 cm2 V–1 s–1 and electron mobilities are in the range of 2.0 × 10–6 to 3.0 × 10–5 cm2 V–1 s–1, depending on the blend composition. UV‐vis spectroscopy and electron diffraction show crystallization of CuPc in the metastable α‐crystal form within the semicrystalline BBL matrix. These CuPc domains develop into elongated ribbon‐like crystalline nanostructures when the blend films are processed in methanol, but not when they are processed in water. On methylene chloride vapor annealing of the blend films, a phase transformation of CuPc from the α‐form to the β‐form is observed, as shown by optical absorption spectroscopy and electron diffraction. Ambipolar charge transport is only observed in the blend films where CuPc crystallized in the elongated ribbon‐like nanostructures (α‐form). Ambipolar behavior is not observed with CuPc in the β‐polymorph. Unipolar hole mobilities as high as 2.0 × 10–3 cm2 V–1 s–1 are observed in these solution‐processed blend field‐effect transistors (FETs) on prolonged treatment in methanol, comparable to previously reported hole mobilities in thermally evaporated CuPc FETs. These results show that ambipolar charge transport and carrier mobilities in multicomponent organic semiconductors are intricately related to the phase‐separated nanoscale and crystalline morphology.
Synthesis of Nanowalled Polymer Microtubes Using Glass Fiber Templates
Authors: Tuncel D. , Matthews J. R. , Anderson H. L.
Published: September 2004

Covalently crosslinked flexible polymer microtubes with wall thicknesses of 1–3 nm, diameters of 2–10 μm, and lengths of 0.1–0.5 mm have been fabricated using glass wool and silica wool as templates. Fluorescent‐dye‐tagged polyamines were adsorbed onto the glass and silica templates and crosslinked by reductive amination with glutaraldehyde and sodium cyanoborohydride, then the templates were dissolved with hydrofluoric acid. Microtubes were prepared from polyallylamine (PAA), polyethyleneimine (PEI), and poly(iminohexamethylene) (PIH) labeled with sulforhodamine B. These flexible hollow structures were characterized by bright‐field and fluorescent optical microscopy and confocal laser scanning microscopy; they adopt open tubular conformations when suspended in water, and dry to give flat ribbons.
Superparamagnetic Hybrid Nanocylinders
Authors: Zhang M. , Estournès C. , Bietsch W. , Müller A. H. E.
Published: September 2004

Well‐defined cylindrical polymer brushes with poly(acrylic acid) (PAA) cores and poly(n‐butyl acrylate) (PnBA) shells have been synthesized via a combination of anionic polymerization and atom transfer radical polymerization. These amphiphilic brushes are unimolecular cylindrical micelles and can be used as single‐molecular templates for the synthesis of inorganic nanoparticles, because the carboxylic acid groups (or carboxylate groups, after neutralization) in the polymer core can coordinate with various metal ions such as Fe3+ and Fe2+. Ultrafine magnetic nanoparticles were successfully synthesized within the core of these polymer brushes, as confirmed by various characterization techniques. Mössbauer spectroscopy and magnetization measurements indicate that the hybrid nanocylinders exhibit interesting superparamagnetic behavior.
Synthesis of 2′‐Deoxynucleosides by Transglycosylation with New Immobilized and Stabilized Uridine Phosphorylase and Purine Nucleoside Phosphorylase
Authors: Ubiali Daniela , Rocchietti Silvia , Scaramozzino Francesca , Terreni Marco , Albertini Alessandra M. , Fernández‐Lafuente Roberto , Guisán José Manuel , Pregnolato Massimo
Published: September 2004

Multimeric uridine phosphorylase (UP) and purine nucleoside phosphorylase (PNP) of Bacillus subtilis have been expressed from genes cloned in Escherichia coli, purified, characterized, immobilized and stabilized on solid support. A new immobilization strategy has been developed for UP onto Sepabeads coated with polyethyleneamine followed by cross‐linking with aldehyde‐dextran. PNP has been immobilized onto glyoxyl‐agarose. At pH 10 and 45 °C these derivatives catalyzed the transglycosylation of 2′‐deoxyuridine to 2′‐deoxyguanosine in high yield (92%). Under the same conditions the not immobilized enzymes were promptly inactivated.
The Catalytic Diastereo‐ and Enantioselective Claisen Rearrangement of 2‐Alkoxycarbonyl‐Substituted Allyl Vinyl Ether
Authors: Abraham Lars , Körner Marleen , Schwab Pia , Hiersemann Martin
Published: September 2004

The catalytic asymmetric Claisen rearrangement of 2‐alkoxycarbonyl‐substituted allyl vinyl ethers that contain two stereogenic double bonds is described. A combination of the highly Lewis acidic [Cu{(S,S)‐tert‐Bu‐box}](H2O)2(SbF6)2 complex and molecular sieves served as catalyst and afforded the Claisen rearrangement products, substituted and functionalized α‐keto esters, in high yield with a remarkable diastereo‐ and enantioselectivity. The influence of ligand structure, counterion and allyl vinyl ether double bond configuration on the stereoselectivity of the rearrangement was briefly investigated. We propose an explanation for the rate accelerating effect of the Lewis acid as well as a stereochemical model which serve to explain and predict the stereochemical course of the copper bis(oxazoline) catalyzed Claisen rearrangement.
N‐Arylamides from Selenium‐Catalyzed Reactions of Nitroaromatics and Amides in the Presence of Carbon Monoxide and Mixed Organic Bases
Authors: Chen Jinzhu , Ling Gang , Yu Zhengkun , Wu Sizhong , Zhao Xiaodan , Wu Xiaowei , Lu Shiwei
Published: September 2004

N‐Arylamides were exclusively obtained in moderate to good yields from selenium‐catalyzed reactions of nitroaromatics with amides in the presence of CO and mixed organic bases Et3N and DBU.
Highly Enantioselective Hydrogenation of Itaconic Acid Derivatives with a Chiral Bisphospholane‐Rh(I) Catalyst
Authors: Almena Juan , Monsees Axel , Kadyrov Renat , Riermeier Thomas H. , Gotov Battsengel , Holz Jens , Börner Armin
Published: September 2004

The new – commercially in multi‐kg quantities available – chiral bisphospholane ligand, catASium® M, has been successfully used in the Rh(I)‐catalysed enantioselective hydrogenation of itaconic acid derivatives. Chiral ß‐substituted succinic acid derivatives were produced in good to excellent enantioselectivities. Turnover frequencies by up to 40,000 h−1 have been achieved.
Synthesis, Oxygenation and Catalytic Oxidation Performance of Crown Ether‐Containing Schiff Base‐Transition Metal Complexes
Authors: Zeng Wei , Li Jianzhang , Mao Zhihua , Hong Zhou , Qin Shengying
Published: September 2004

Mono‐Schiff bases containing a crown ether ring (HL1, HL2, HL3 and HL4) and their transition metal complexes were synthesized and characterized by 1H NMR, IR, and mass spectroscopy as well as elemental analysis. The oxygenation constants (K) of Schiff base‐Co(II) complexes were measured over the range of −5 to +25 °C, and the values of ΔH° and ΔS° were calculated based on these K values. Using Mn(III)‐Schiff base complexes, the biomimetic catalytic oxidation of styrene to benzaldehyde was carried out with 100% selectivity. Comparison of this complex with analogues not containing a crown ether moiety clearly demonstrated the influence of crown ether ring on the dioxygen affinities and biomimetic catalytic oxidation performance of the Schiff base complexes.
Three‐Component Staudinger‐Type Stereoselective Synthesis of C‐Glycosyl‐β‐lactams and their Use as Precursors for C‐Glycosyl Isoserines and Dipeptides. A Polymer‐Assisted Solution‐Phase Approach
Authors: Dondoni Alessandro , Massi Alessandro , Sabbatini Simona , Bertolasi Valerio
Published: September 2004

A collection of 4‐(C‐galactosyl)‐ and 4‐(C‐ribosyl)‐β‐lactams featuring different substituents at C‐3 and N‐1 was prepared by combining in a one‐pot procedure a formyl C‐glycoside, a primary amine, and a substituted acetyl chloride in the presence of base (Staudinger‐type reaction). Sulfonyl chloride and aminomethylated resins were used in sequence to remove excess of components and by‐products. Two pure C‐glycosyl‐β‐lactams were effectively transformed into C‐glycosyl‐N‐Boc‐β‐amino‐α‐hydroxy esters (C‐glycosyl isoserines) and a C‐ribosyl dipeptide via base‐promoted heterocycle ring opening by methanol and L‐phenylalanine methyl ester, respectively.
Synthesis and Derivatization of Substituted (R)‐ and (S)‐ C‐Allylglycines
Authors: Zhang Nong , Münch Winfried , Nubbemeyer Udo
Published: September 2004

Various (R)‐ and (S)‐C‐allylglycine derivatives were synthesized by means of an auxiliary controlled diastereoselective aza‐Claisen rearrangement. Starting from (S)‐configured auxiliaries derived from optically active proline, an aza‐Claisen rearrangement enabled us to synthesize α(R)‐configured γ,δ‐unsaturated amides. Since (R)‐allylglycine derivatives could be directly generated by reacting N‐allylproline derivatives and various protected glycine fluorides, the corresponding (S)‐enantiomers were built‐up via an initial α‐chloroacetyl chloride rearrangement and a subsequent chloride azide substitution with complete inversion of the configuration. High diastereoselectivities were obtained (>15 : 1). The auxiliary could be efficiently removed by organolithium reactions of the amides furnishing α‐amino ketones. Another allyllithium addition allowed us to introduce a second allyl chain with high diastereoselectivity. Final ring closures by means of metatheses using Grubbs' (I) catalyst gave raise to the formation of enantiopure phenanthridines and cyclohexenes displaying defined substitution patterns ready for alkaloid total syntheses.
Recyclable Tridentate Stable Palladium(II) PCP‐Type Catalysts Supported on Silica for the Selective Synthesis of Lactones
Authors: Chanthateyanonth Ratana , Alper Howard
Published: September 2004

Five‐ or seven‐membered ring lactones are synthesized, in good selectivity and high yields, by the cyclocarbonylation reaction of 2‐allylphenols, using a tridentate diphosphinoaryl ligand (PCP‐type) palladium(II) catalyst immobilized on silica (A) and silica supported dendrimers (B, C and D). These immobilized catalysts, which are highly active and can be recycled by simple filtration in air, and reused with only moderate loss of activity, combine the advantages of heterogeneous and homogeneous catalysts. These complexes are also stable towards oxygen and moisture.
Stetter Reaction in Room Temperature Ionic Liquids and Application to the Synthesis of Haloperidol
Authors: Anjaiah Siddam , Chandrasekhar Srivari , Grée René
Published: September 2004

Imidazolium‐type room temperature ionic liquids (RTILs) have been used for the Stetter reaction, affording the desired 1,4‐dicarbonyl compounds in good yields. Thiazolium salts and Et3N are efficient catalysts for this reaction performed in ionic liquid. The possibility to recycle and reuse the solvent has been demonstrated, although it was not possible to recycle the thiazolium catalyst. This method was used in the total synthesis of haloperidol.
Water‐Tolerant and Reusable Catalysts for Direct Ester Condensation between Equimolar Amounts of Carboxylic Acids and Alcohols
Authors: Nakayama Masaya , Sato Atsushi , Ishihara Kazuaki , Yamamoto Hisashi
Published: September 2004

ZrOCl2⋅8 H2O and HfOCl2⋅8 H2O are highly effective, water‐tolerant, and reusable homogeneous catalysts for direct ester condensation between equimolar amounts of carboxylic acids and alcohols. Notably, zirconium(IV) salts such as ZrOCl2⋅8 H2O and Zr(OAc)x(OH)y are potential green catalysts due to their low toxicity, commercial availability at low cost, ease of handling, high catalytic activity, and reusability.
mTOR cascade activation distinguishes tubers from focal cortical dysplasia
Authors: Baybis Marianna , Yu Jia , Lee Allana , Golden Jeff A. , Weiner Howard , McKhann Guy , Aronica Eleonora , Crino Peter B.
Published: September 2004

Balloon cells (BCs) in focal cortical dysplasia (FCD) and giant cells (GCs) in tubers of the tuberous sclerosis complex (TSC) share phenotypic similarities. TSC1 or TSC2 gene mutations in TSC lead to mTOR pathway activation and p70S6kinase (phospho‐S6K) and ribosomal S6 (phospho‐S6) protein phosphorylation. Phospho‐S6K, phospho‐S6, and phospho‐S6K–activated proteins phospho‐STAT3 and phospho‐4EBP1 were detected immunohistochemically in GCs, whereas only phospho‐S6 was observed in BCs. Expression of four candidate gene families (cell signaling, cell adhesion, growth factor/receptor, and transcription factor mRNAs) was assayed in single, microdissected phospho‐S6–immunolabeled BCs and GCs as a strategy to define whether BCs and GCs exhibit differential transcriptional profiles. Among 60 genes, differential expression of 24 mRNAs distinguished BCs from GCs and only 4 genes showed similar expression profiles between BCs and GCs. Tuberin mRNA levels were reduced in GCs from TSC patients with TSC2 gene mutations but were unchanged in BCs. Phospho‐S6K, ‐S6, ‐STAT3, and ‐4EBP1 expression in GCs reflects loss of hamartin‐tuberin–mediated mTOR pathway inhibition. Phospho‐S6 expression alone in BCs does not support mTOR cascade activation in FCD. Differential gene expression profiles in BCs and GCs supports the hypothesis that these cell types derive by distinct pathogenic mechanisms. Ann Neurol 2004
Familial aggregation of Parkinson's disease: The Mayo Clinic family study
Authors: Rocca Walter A. , McDonnell Shannon K. , Strain Kari J. , Bower James H. , Ahlskog J. Eric , Elbaz Alexis , Schaid Daniel J. , Maraganore Demetrius M.
Published: September 2004

Data on the familial aggregation of Parkinson's disease (PD) remain conflicting. We conducted a historical cohort study of 1,001 first‐degree relatives of 162 probands with PD and of 851 relatives of 147 control probands representative of the population of Olmsted County, Minnesota (from 1976 through 1995). In addition, we studied 2,713 first‐degree relatives of 411 probands with PD referred to the Mayo Clinic from 1996 through 2000 and 625 spouses of PD or control probands. Whenever possible, relatives were interviewed and screened for parkinsonism either directly or through a proxy, and those who screened positive were examined or a copy of their medical record was obtained to confirm the diagnosis (family study method). Thirty relatives of population‐based PD probands, 18 relatives of population‐based control probands, 65 relatives of referral PD probands, and 8 spouses had developed PD. Combining population‐based with referral PD probands and population‐based control probands with spouses, the relative risk was modestly increased (relative risk, 1.71; 95% confidence interval, 1.11–2.64). Relatives of probands with younger onset (≤66 years; first tertile) had a more significantly increased risk (relative risk, 2.62; 95% confidence interval, 1.66–4.15), whereas relatives of probands with later onset had no increased risk. The relative risk decreased when the incidence of all types of parkinsonism was considered. Ann Neurol 2004;56:495–502
Cytochrome c oxidase biogenesis in a patient with a mutation in COX10 gene
Authors: Coenen Marieke J. H. , van den Heuvel Lambert P. , Ugalde Cristina , ten Brinke Marike , Nijtmans Leo G. J. , Trijbels Frans J. M. , Beblo Skadi , Maier Esther M. , Muntau Ania C. , Smeitink Jan A. M.
Published: September 2004

We report a cytochrome c oxidase (COX)–deficient patient, clinically affected with Leigh‐like disease, with a homozygous mutation in the COX10 start codon. Two‐dimensional gel electrophoresis showed a decrease of fully assembled COX without the accumulation of partially assembled COX subcomplexes. Western blot analysis with antibodies directed to COX subunits I, II, and IV showed a decrease of these subunits in this patient compared with control. Overexpression of the COX10 protein in the patient's fibroblasts proved that the detected mutation was indeed the disease cause. Ann Neurol 2004;56:560–564
Reduction of cortical TrkA but not p75NTR protein in early‐stage Alzheimer's disease
Authors: Counts Scott E. , Nadeem Muhammad , Wuu Joanne , Ginsberg Stephen D. , Saragovi H. Uri , Mufson Elliott J.
Published: September 2004

Degeneration of cholinergic nucleus basalis (NB) cortical projection neurons is associated with cognitive decline in late‐stage Alzheimer's disease (AD). NB neuron survival is dependent on coexpression of the nerve growth factor (NGF) receptors p75NTR and TrkA, which bind NGF in cortical projection sites. We have shown previously a significant reduction of NB perikarya expressing p75NTR and TrkA protein during the early stages of AD. Whether there is a concomitant reduction in cortical levels of these receptors during the progression of AD is unknown. p75NTR and TrkA protein was evaluated by quantitative immunoblotting in five cortical regions (anterior cingulate, superior frontal, superior temporal, inferior parietal, and visual cortex) of individuals clinically diagnosed with no cognitive impairment (NCI), mild cognitive impairment (MCI), mild/moderate AD, or severe AD. Cortical p75NTR levels were stable across the diagnostic groups. In contrast, TrkA levels were reduced approximately 50% in mild/moderate and severe AD compared with NCI and MCI in all regions except visual cortex. Mini‐Mental Status Examination scores correlated with TrkA levels in anterior cingulate, superior frontal, and superior temporal cortex. The selective reduction of cortical TrkA levels relative to p75NTR may have important consequences for cholinergic NB function during the transition from MCI to AD. Ann Neurol 2004
A novel locus for pure recessive hereditary spastic paraplegia maps to 10q22.1‐10q24.1
Authors: Meijer Inge A. , Cossette Patrick , Roussel Julie , Benard Melanie , Toupin Sylvie , Rouleau Guy A.
Published: September 2004

The hereditary spastic paraplegias (HSPs) are a group of clinically and genetically heterogeneous disorders characterized by progressive lower‐limb spasticity. In this study, we performed linkage analysis on an autosomal recessive pure HSP family and mapped the disease to chromosome 10q22.1‐10q24.1, a locus partially overlapping the existing SPG9 locus. We have either identified a novel locus for pure recessive HSP (SPG27), or we have found the first case of allelic disorders with different mode of inheritance in HSP. If the disorders are indeed allelic, our results have reduced the SPG9 interval by 3Mb with D10S536 and D10S1758 as flanking markers. Ann Neurol 2004;56:579–582
Titelbild: Die innere Struktur des Kerns von Nanokapseln reagiert auf eine Kommunikation der Hüllen (Angew. Chem. 39/2004)
Authors: Cave Gareth W. V. , Antesberger Jochen , Barbour Leonard J. , McKinlay Robert M. , Atwood Jerry L.
Published: September 2004

Nanokapseln lagern sich durch nichtkovalente Wechselwirkungen zusammen und schließen ein Volumen von über 1300 Å3 ein. Supramolekulare Wechselwirkungen zwischen zwei Nanokapseln beeinflussen die dynamische Struktur der Kapselwände. Dadurch verändert sich die Packung und Fluidität der Gastmatrix enorm. In ihrer Zuschrift auf S. 5375 ff. geben J. L. Atwood et al. einen Einblick in die Wechselwirkungen und die Fluidität dieses “neuen Aggregatzustands der Materie”.
Cover Picture: Inner Core Structure Responds to Communication between Nanocapsule Walls (Angew. Chem. Int. Ed. 39/2004)
Authors: Cave Gareth W. V. , Antesberger Jochen , Barbour Leonard J. , McKinlay Robert M. , Atwood Jerry L.
Published: September 2004

Nanoscale molecular capsules are assembled by means of noncovalent interactions and enclose over 1300 Å3 of molecular space. The supramolecular interactions between two independent nanocapsules lead to changes in the dynamic structure of the capsule walls. This dramatically alters the packing and fluidity of the guest matrix within the host. In their Communication on page 5263 ff., J. L. Atwood and co‐workers provide valuable insight into the interactions and fluidity of the so‐called “new phase of matter”.
Konzeptionelles Entwerfen und Konstruieren von Integralen Betonbrücken
Authors: Schüller Matthias
Published: September 2004

Bei Betonbrücken werden heute oft Fugen und Lager angeordnet. Die damit verbundene Trennung von Über‐ und Unterbauten hat sowohl funktionale als auch gestalterische Nachteile. Im folgenden wird versucht, die Vorteile der in Vergessenheit geratenen monolithischen Bauweise anhand von neuen Beispielen aufzuzeigen. Dabei werden der konstruktiven Durchbildung und der Formgebung des Tragwerks unter dem Aspekt der Dauerhaftigkeit besondere Aufmerksamkeit geschenkt.
Betrachtungen zur Verkehrslastannahme bei Holzbalken/Beton‐Verbunddecken
Authors: Resch Eckart , Schmidt Jörg , Kaliske Michael , Schneider Werner
Published: September 2004

Gemäß DIN 1055‐T3 ist für Wohnungsdecken ohne ausreichende Quertragwirkung, z. B. Holzbalkendecken, eine Verkehrslast von 2,0 kN/m2 anzusetzen. Massivdecken, die eine ausreichende Quertragwirkung aufweisen, sind dagegen für eine Verkehrslast von 1,5 kN/m2 zu bemessen. Holzbalken/Beton‐Verbunddecken wirken weder wie reine Massivdecken noch wie Holzbalkendecken. Deshalb wird in diesem Beitrag die Querlastverteilung dieser Verbundkonstruktionen mit verschiedenen Stützweiten, Balkenabständen und Verbundsteifigkeiten untersucht, um Aussagen zur Verkehrslastannahme zu gewinnen. Es wird ein Vorschlag zur Bestimmung der maßgebenden Verkehrslastannahme praxisgerecht aufgezeigt.
Neue Wege der Feuchtemessung und Beurteilung von Estrichen und Betonen
Authors: Rieche Günter
Published: September 2004

Der vorliegende Beitrag schlägt vor, in Fußbodenkonstruktionen an Stelle des massebezogenen Wassergehaltes u(x,t) die relative Luftfeuchte ϕi(x,t) in den Poren des porösen Baustoffes (Estrich/Beton) zu messen. Im stationären Fall oder im quasi‐stationären Fall sind beide Größen durch die Sorptionsisotherme des Baustoffes miteinander verbunden. Es steht ein Meßverfahren für die Bestimmung der relativen Luftfeuchte ϕi(x,t) zur Verfügung. Die Bewertung der Fußbodenkonstruktionen soll dann zukünftig anhand von Grenzwerten ϕzul für die relative Luftfeuchte in den Baustoffporen erfolgen. Für verschiedene Anwendungen in der Praxis werden hier Grenzwerte ϕzul vorgeschlagen.
Einfluß der Vorlagerung auf das Temperaturverhalten von selbstverdichtendem Beton
Authors: Horvath Johannes , Hertel Claudia , Dehn Frank , Schneider Ulrich
Published: September 2004

Untersuchungen zum Brand‐ und Abplatzverhalten von selbstverdichtenden Betonen zeigten, inwiefern sich unterschiedliche Polypropylenfasergehalte sowie die Vorlagerungsbedingungen (an Luft oder feucht) hinsichtlich des Temperaturverhaltens von selbstverdichtendem Beton auswirken. Nachfolgend wird über eine Auswahl von Versuchen berichtet.
An active insect kinin analog with 4‐aminopyroglutamate, a novel cis‐peptide bond, type VI β‐turn motif
Authors: Nachman Ronald J. , Kaczmarek Krzysztof , Williams Howard J. , Coast Geoffrey M. , Zabrocki Janusz
Published: September 2004

The insect kinins are potent diuretic peptides that preferentially form a cis‐Pro, type VI β‐turn. An insect kinin analog containing (2S,4S)‐4‐aminopyroglutamate, a novel cis‐peptide bond, type VI β‐turn motif, demonstrates significant activity in the physiological range in a cricket diuretic assay. This is the first instance of a 4‐aminopyroglutamate analog of a peptide with a preference for a type VI turn that demonstrates significant bioactivity. The results provide further confirmatory evidence for the active conformation of the insect kinins, and a new scaffold with which to design biostable, peptidomimetic analogs capable of disrupting critical insect kinin‐regulated processes in insects. © 2004 Wiley Periodicals, Inc. Biopolymers, 2004
Resection of the rectum and total excision of the internal anal sphincter with smooth muscle plasty and colonic pouch for treatment of ultralow rectal carcinoma
Authors: Vorobiev G I , Odaryuk T S , Tsarkov P V , Talalakin A I , Rybakov E G
Published: September 2004

Background

Intersphincteric resection can provide tumour-free margins for rectal tumours located 0–1 cm above the dentate line. However, the internal anal sphincter (IAS) is partially or totally resected and some degree of anal incontinence may develop. A novel technique of smooth muscle plasty of the IAS and colonic pouch construction is described, along with an assessment of morbidity, oncological results and functional outcome.

Patients and methods

Between 1997 and 2002, 27 patients (16 men; median age 55 (range 26–75) years) were operated on for T2–3 N0–1 M0 rectal carcinoma located a median of 1·0 (range 0·5–1·5) cm from the dentate line. Resection of the IAS was performed transanally. A smooth muscle cuff, fashioned from the muscular layer of colon, and a colonic pouch were used for anorectal reconstruction.

Results

There were no perioperative deaths. Anastomotic leakage developed in two patients. After a median follow-up of 38 (range 14–66) months no local recurrence was detected. Distant metastases occurred in three patients, two of whom died. Perfect functional outcome was achieved in 22 of 26 patients. At 6 months after surgery the mean(s.d.) resting anal pressure was 49(8) mmHg.

Conclusion

In selected patients intersphincteric resection does not compromise the oncological result. The suggested anorectal reconstruction may improve the functional outcome.
Abdominoperineal resection is associated with poor oncological outcome
Authors: Law W L , Chu K W
Published: September 2004

Background

The aim of this study was to compare the operative results and oncological outcomes of patients who had mid or distal rectal cancer treated by abdominoperineal resection (APR) with those treated without sphincter ablation (non-APR).

Methods

Five hundred and four consecutive patients (308 men and 196 women) with rectal cancer within 12 cm from the anal verge underwent radical resection with curative intent. Sharp mesorectal dissection was used. Operative results and long-term outcomes were compared between those treated by APR and those by non-APR.

Results

Sixty-nine patients had APR and 435 patients were treated with radical resection without perineal resection (anterior resection, 419; Hartmann's operation, 16). The overall operative mortality and morbidity rates were 1·6 and 31·0 per cent respectively. Age, sex, duration of surgery, blood loss, duration of hospital stay, operative mortality and overall morbidity were similar in the two groups. Local recurrence was more frequent after curative APR than after non-APR (23 versus 10·2 per cent at 5 years; P = 0·010). Five-year cancer-specific survival rates after APR and non-APR were 60 and 74·0 per cent respectively (P = 0·006). APR was an independent factor for poor cancer-specific survival in multivariate analysis.

Conclusion

Although postoperative mortality and morbidity rates were similar in patients with or without sphincter ablation, local control and survival were worse in those treated by APR.
Medical examinations for child sexual abuse in Scotland: good enough practice?
Authors: Mok Jacqueline Y. Q. , Busuttil Anthony
Published: September 2004

This questionnaire survey of a representative sample of practitioners in Scotland sought to establish speciﬁcally how widely guidance on child protection issued by the Scottish Executive Health Department was being followed by practitioners, NHS Trusts and health boards. It aimed to identify the medical practitioners involved and the range of current practice in child sexual abuse examinations throughout Scotland. The results suggest that the medical assessment of children who disclose sexual abuse is a low‐volume, highly specialized activity, practised by about one in ﬁve paediatricians and forensic medical examiners in Scotland. Most (79%) are aged between 41 and 60 years; 59.8% have less than 10 years' experience in the ﬁeld; and the majority (86.3%) perform fewer than two examinations per week. Available guidance is comprehensive and uniform, highlighting the importance of joint specialist working, use of the colposcope for photodocumentation, training and continuing professional development in this specialized area of work. Despite this, the results of our survey of practitioners show that throughout Scotland, the care offered to children and the service provided to the courts are suboptimal. Copyright © 2004 John Wiley & Sons, Ltd.
Resilience and risk factors associated with experiencing childhood sexual abuse
Authors: Wilcox Daniel T. , Richards Fiona , O'Keeffe Zerine C.
Published: September 2004

The effects of child sexual abuse are wide‐ranging and impact on children, families and health/social care systems. The authors review this literature, examining the shortcomings of the ‘victim–offender’ model, and consider the complex, multifactorial nature of this question. Factors associated with a progression from victim to perpetrator are explored and the prevalence of abuse in the general population is also discussed. Protective as well as risk factors are considered and the pivotal role of ‘personal reliance’ is considered as it relates to empowering damaged young people to become healthy adults. The authors also discuss implications for the treatment of young people who become abusers. Two case examples are brieﬂy reported upon and the article concludes with a consideration of ways to helpfully address the needs of children who become sexual perpetrators. Copyright © 2004 John Wiley & Sons, Ltd.
The interface between the child welfare and criminal justice systems in England
Authors: Gray Jenny
Published: September 2004

The development of government guidance can seem a mysterious process to those outside government. This paper, which draws on the author's experience, is intended to give some insight into how guidance in two areas—child witnesses and children involved in prostitution—was developed within the existing legal framework. Since that time, the Sexual Offences Act 2003 has come into force in England and Wales and the Children Bill is currently before Parliament. The paper begins by setting out the key legislation, regulations and guidance that underpinned the child welfare and criminal justice systems as they related to child protection at the time the guidance was being developed. It then describes how the different guidance documents relate to each other and the implications for practice. The development of speciﬁc guidance is drawn upon to illustrate some of the tensions that had to be resolved during the drafting and the processes by which they were ﬁnalized for approval by the Government. A key area requiring careful consideration was the differences between the family and criminal justice systems. In the former, the welfare of the child is paramount when making decisions and in the latter, the court has a duty to ensure the defendant has a fair trial. Copyright © 2004 John Wiley & Sons, Ltd.
The Concept of “Buffering” in Systems and Control Theory: From Metaphor to Math
Authors: Schmitt Bernhard M.
Published: September 2004

The paradigm of “buffering” is used increasingly for the description of diverse “systemic” phenomena encountered in evolutionary genetics, ecology, integrative physiology, and other areas. However, in this new context, the paradigm has not yet matured into a truly quantitative concept inasmuch as it lacks a corresponding quantitative measure of “systems‐level buffering strength”. Here, I develop such measures on the basis of a formal and general approach to the quantitation of buffering action. “Systems‐level buffering” is shown to be synonymous with “disturbance rejection” in feedback‐control systems, and can be quantitated by means of dimensionless proportions between partial flows in two‐partitioned systems. The units allow either the time‐independent, “static” buffering properties or the time‐dependent, “dynamic” ones to be measured. Analogous to this “resistance to change”, one can define and measure the “conductance to change”; this quantity corresponds to “set‐point tracking” in feedback‐control systems. Together, these units provide a systematic framework for the quantitation of buffering action in systems biology, and reveal the common principle behind systems‐level buffering, classical acid–base buffering, and multiple other manifestations of buffering.
Synthesis of GTP‐Derived Ras Ligands
Authors: Soulère Laurent , Aldrich Courtney , Daumke Oliver , Gail Robert , Kissau Lars , Wittinghofer Alfred , Waldmann Herbert
Published: September 2004

A practical and convenient method for the synthesis of acid‐ and base‐sensitive GTP analogues carrying a further substituent at the terminal phosphate has been developed. Key to the successful synthesis of these potential ligands of the Ras protein is the use of Pd0‐sensitive allyl protecting groups in a one‐pot synthesis that avoids evaporation steps. Initial biochemical analysis of a representative compound revealed that such GTP analogues can bind to Ras and might open up the possibility of developing small molecules that can act as deactivators of oncogenic Ras.
The Systems Biology of Glycosylation
Authors: Murrell Michael P. , Yarema Kevin J. , Levchenko Andre
Published: September 2004

Glycosylation can have a profound influence on the function of a variety of eukaryotic cells. In particular, it can affect signal transduction and cell–cell communication properties and thus shape critical cell decisions, including the regulation of differentiation and apoptosis. Regulation of glycosylation has multiple layers of complexity, both structural and functional, which make its experimental and theoretical analysis difficult to perform and interpret. Novel research methodologies provided by systems biology can help to address many outstanding issues and integrate glycosylation with other metabolic and cell regulation processes. Here we review the toolbox available for biochemical systems analysis of glycosylation.
Spatial and Temporal Sequence of Events in Cell Adhesion: From Molecular Recognition to Focal Adhesion Assembly
Authors: Cohen Miriam , Joester Derk , Geiger Benjamin , Addadi Lia
Published: September 2004

A new concept that attributes a pivotal role to the pericellular coat in the regulation of the early stages of cell adhesion is presented. Quick, adaptable, and transient adhesion through multiple cooperative weak interactions provides the cell with an additional level of modulation in the decision‐making process that precedes the commitment to adhesion at a particular site. Hyaluronan emerges as a modulator of cell adhesion in certain cells, mediating binding or repulsion through its polyelectrolyte character, in addition to its chirality and molecular‐recognition properties. The biophysical properties of hyaluronan as well as its ultrastructural organization are analyzed in relation to this proposed function.
Amygdalostriatal projections in reptiles: A tract‐tracing study in the lizardPodarcis hispanica
Authors: Novejarque Amparo , Lanuza Enrique , Martínez‐García Fernando
Published: September 2004

Whereas the lacertilian anterior dorsal ventricular ridge contains unimodal sensory areas, its posterior part (PDVR) is an associative center that projects to the hypothalamus, thus being comparable to the amygdaloid formation. To further understand the organization of the reptilian cerebral hemispheres, we have used anterograde and retrograde tracing techniques to study the projections from the PDVR and adjoining areas (dorsolateral amygdala, DLA; deep lateral cortex, dLC; nucleus sphericus, NS) to the striatum in the lizardPodarcis hispanica. This information is complemented with a detailed description of the organization of the basal telencephalon ofPodarcis. The caudal aspect of the dorsal ventricular ridge projects nontopographically mainly (but not exclusively) to the ventral striatum. The NS projects bilaterally (with strong ipsilateral dominance) to the nucleus accumbens, thus recalling the posteromedial cortical amygdala of mammals. The PDVR (especially its lateral aspect) and the dLC project massively to a continuum of structures connecting the striatoamygdaloid transition area (SAT) and the nucleus accumbens (rostrally), the projection arising from the dLC being probably bilateral. Finally, the DLA projects massively and bilaterally to both the ventral and dorsal striatum, including the SAT. Our findings lend further support to the view that the PDVR and neighboring structures constitute the reptilian basolateral amygdala and indicate that an emotional brain was already present in the ancestral amniote. These results are important to understand the comparative significance of the caudal aspect of the amniote cerebral hemispheres, and specifically challenge current views on the nature of the avian caudal neostriatum. J. Comp. Neurol. 479:287–308, 2004. © 2004 Wiley‐Liss, Inc.
Immunohistochemical distribution of tachykinins in the CNS of the lamprey Petromyzon marinus
Authors: Auclair François , Lund James P. , Dubuc Réjean
Published: September 2004

The presence of tachykinins in the CNS of vertebrates has been known for many decades, and numerous studies have described their distribution in mammals. Tachykinins were also reported in the CNS of lampreys using immunohistochemistry, chromatography, and radioimmunoassay methods, but the use of substance P (SP)‐specific antibodies to reveal those tachykinins could have led to an underestimation of their number in this genus. Therefore, we carried out a new immunohistochemical study on Petromyzon marinus using a commercial polyclonal antibody that binds not only to mammalian SP, but also to other neurokinins. This antibody labeled all previously described lamprey tachykinin‐containing neuronal populations, but more important, labeled new populations in several parts of the brain. These include the dorsal gray of the rostral spinal cord, the dorsal column nuclei, the octavolateral area, the nucleus of the solitary tract, the medial rhombencephalic reticular formation, the lateral tegmentum of the rostral rhombencephalon, the torus semicircularis, the optic tectum, the habenula, the mammillary area, the dorsal thalamic area, the lateral hypothalamus, and the septum area. Preabsorption experiments confirmed the binding of the antibody to neurokinins and allowed us to propose that the CNS of P. marinus contains at least two different tachykinins. J. Comp. Neurol. 479:328–346, 2004. © 2004 Wiley‐Liss, Inc.
Palladium‐catalyzed Suzuki reaction using 1,3‐dialkylbenzimidazol‐2‐ylidene ligands in aqueous media
Authors: Özdemir İsmail , Gök Yetkin , Gürbüz Nevin , Çetinkaya Engin , Çetinkaya Bekir
Published: September 2004

From readily available starting compounds, six functionalized 1,3‐dialkylbenzimidazolium salts (2a–c and 4a–c) have been prepared and characterized by conventional spectroscopic methods and elemental analyses. A highly effective, easy to handle, and environmentally benign process for palladium‐mediated Suzuki cross‐coupling was developed. The in situ prepared three‐component systems Pd(OAc)2/1,3‐dialkylbenzimidazolium chlorides and Cs2CO3 catalyze quantitatively the Suzuki cross‐coupling of deactivated aryl chlorides. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:419–423, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20034
Synthesis, structure, and reactivity of a symmetrically substituted 9‐phosphatriptycene oxide and its derivatives
Authors: Agou Tomohiro , Kobayashi Junji , Kawashim Takayuki
Published: September 2004

Novel 9‐phosphatriptycenes were synthesized by utilizing ortho‐lithiation of a triarylphosphine oxide as a key step. The structural analysis of the 9‐phosphatriptycene oxide revealed its highly distorted structure around the phosphorus atom, which is consistent with the up‐field shift in the 31P NMR spectrum. The 9‐phosphatriptycene and its chalcogenides were synthesized by ordinary methods, and the spectral comparisons of these chalcogenides indicated the large s‐character of the lone‐pair orbital or the phosphorus–chalcogen σ bonds of those species. The 9‐phosphatriptycene oxide was reacted with lithium naphthalenide to give the ring‐opened products. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:437–446, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20038
2‐Aryl‐dibenzo‐1,2‐oxaphosphorine as a ligand in borane and in Pt(II) complexes
Authors: Keglevich György , Szelke Helga , Kerényi Andrea , Imre Tímea , Ludányi Krisztina , Dukai József , Nagy Ferenc , Arányi Péter
Published: September 2004

Optimum conditions for the synthesis of aryl‐dibenzo‐oxaphosphorines (2) from the corresponding phosphonous chloride (1) were explored to avoid the formation of by‐products (e.g., 4–6). The aryl‐dibenzo‐oxaphosphorines (2) were converted to the P‐oxides (3), and were utilized in the synthesis of phosphinite‐boranes 7 and Pt(II) complexes 8. Depending on the aryl substituent, the Pt(II) complex (8) was formed with cis and trans geometry. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:459–463, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20042
The identification of some novel four‐membered ring cyclic triphosphenium ions in solution
Authors: Dillon Keith B. , Monks Philippa K. , Olivey Richard J. , Karsch Hans H.
Published: September 2004

The first four‐membered ring cyclic triphosphenium ions with carbon substituents (methyl or cyclohexyl) on the outer phosphorus atoms have been identified in solution by 31P NMR spectroscopy. The cyclohexyl derivative in the presence of [SnCl6]2− as counterion was stable enough for methylation by methyl triflate to be carried out. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:464–467, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20043
A simple, convenient and expeditious approach to cineol
Authors: Bugarčić Zorica M. , Dunkić Jelena D. , Mojsilović Biljana M.
Published: September 2004

A convenient two‐step protocol preparation of cineol (1‐isopropyl‐4‐methyl‐7‐oxabicyclo[2,2,1]heptane) from α‐terpineol (p‐menth‐1‐en‐8‐ol) is reported. The phenylselenoetherification of α‐terpineol with PhSeX (X = Cl, Br, I) as a key step is described. α‐Terpineol reacts with PhSeX to form the corresponding phenylselenoether in short reaction time and in quantitative yield. A subsequent reduction with Bu3SnH to cineol proceeds in high yield (98%) © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:468–470, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20044
Leflunomide protects from T-cell-mediated liver injury in mice through inhibition of nuclear factor κB
Authors: Imose Motoaki , Nagaki Masahito , Kimura Kiminori , Takai Shinji , Imao Motohiro , Naiki Takafumi , Osawa Yosuke , Asano Takahiko , Hayashi Hideki , Moriwaki Hisataka
Published: September 2004

Leflunomide is a novel immunosuppressive and anti-inflammatory agent for the treatment of autoimmune disease. The aim of this study was to investigate whether leflunomide protects from liver injury induced by concanavalin A (Con A), a T-cell-dependent model of liver damage. BALB/c mice were injected with 25 mg/kg Con A in the presence or absence of 30 mg/kg leflunomide. Liver injury was assessed biochemically and histologically. Levels of circulating cytokines and expressions of cytokine messenger RNA (mRNA) in the liver and the spleen were determined. Treatment with leflunomide markedly reduced serum transaminase activities and the numbers of dead liver cells. Leflunomide significantly inhibited increases in plasma tumor necrosis factor alpha (TNF-α) and interleukin 2 concentrations, and also reduced TNF-α mRNA expression in the liver after administration of Con A. These findings were supported by the results in which leflunomide administration decreased the number of T lymphocytes infiltrating the liver as well as inhibiting their production of TNF-α. Activation of nuclear factor κB (NF-κB), which regulates TNF-α production, was inhibited in the liver of mice treated with leflunomide, resulting in a reduction of TNF-α production from lymphocytes infiltrating the liver. In conclusion, leflunomide is capable of regulating T-cell-mediated liver injury in vivo and that this event may depend on the decrease of TNF-α production in the liver through inhibition of NF-κB activation caused by leflunomide. (Hepatology 2004.)
Comparative analysis of the conformational profile of substance P using simulated annealing and molecular dynamics
Authors: Corcho Francesc J. , Canto Josep , Perez Juan J.
Published: September 2004

The present study describes an extensive conformational search of substance P using two different computational methods. On the one hand, the peptide was studied using the iterative simulated annealing, and on the other, molecular dynamics simulations at 300 and 400 K. With the former method, the peptide was studied in vacuo with a dielectric constant of 80, whereas using the latter study the peptide was studied in a box of TIP3P water molecules. Analysis of the results obtained using both methodologies was carried out using an in‐house methodology using a cluster analysis method based on information theory. Comparison of the two sampling methodologies and the different environment used in the calculations is also analyzed. Finally, the conformational motifs that are characteristic of substance P in a hydrophilic environment are presented and compared with the experimental results available in the literature. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1937–1952, 2004
Towards automation of palynology 3: pollen pattern recognition using Gabor transforms and digital moments
Authors: Zhang Y. , Fountain D. W. , Hodgson R. M. , Flenley J. R. , Gunetileke S.
Published: September 2004

The classification of pollen grains using texture information in combination with shape features is presented in this paper. The surface texture of pollen is characterised by using Gabor transforms, the geometric shape is described by using moment invariants, and the pollen grains are classified by an artificial neural network. In an experiment with five types of pollen grains, more than 97% of samples are correctly classified. Copyright © 2004 John Wiley & Sons, Ltd.
Kinetic and equilibrium study of the reaction of nitroprusside and hydroxide ions: Influence of ionic strength using Pitzer model
Authors: Rubín Eugenia , Rodríguez Pilar , Brandariz Isabel , de Vicente Manuel E. Sastre
Published: September 2004

A kinetic and equilibrium study of the addition reaction of hydroxide ions to nitroprusside has been carried out in this paper. Rate and equilibrium constants at different salt concentrations (up to 4 mol kg−1) were obtained, and the influence of ionic strength was studied by means of Pitzer equations. This model is of special interest because it is able to explain the experimental behavior at high ionic strength, when Debye–Huckel limiting law is no longer valid. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 650–660, 2004