bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemoselective Heterocyclization and Pharmacological Activities of New Heterocycles: Synthesis of New Phospha Heterobicyclic Systems Containing the 1,2,4‐Triazine Moiety. Part 9. Straightforward Synthesis of New Fluorine‐Bearing 5‐Phospha‐1,2,4‐triazine/1,2,4‐triazepine‐3‐thiones
Authors: Abdel‐Rahman R. M.
Published: October 2004

For Abstract see ChemInform Abstract in Full Text.
1,1‐Dithiolato Ligands
Authors: Haiduc I.
Published: October 2004

For Abstract see ChemInform Abstract in Full Text.
A Comparison of Photoinduced Intramolecular Hydrogen‐Atom Transfer of Strain‐Free Planar 1,4‐Dimethylanthraquinone with that of Sterically Strained 1,4‐Hexyl‐bridged Anthraquinone
Authors: Nakayama T. , Miki S. , Shin H. , Hamanoue K.
Published: October 2004

For Abstract see ChemInform Abstract in Full Text.
Recent Advances in the Synthesis of Carbonyl Compounds by Palladium‐Catalyzed Oxidative Carbonylation Reactions of Unsaturated Substrates
Authors: Gabriele Bartolo , Salerno Giuseppe , Costa Mirco , Chiusoli Gian Paolo
Published: October 2004

For Abstract see ChemInform Abstract in Full Text.
The α‐Effect and Its Modulation by Solvent
Authors: Buncel Erwin , Um Ik‐Hwan
Published: October 2004

For Abstract see ChemInform Abstract in Full Text.
Use of Bile Acids in Pharmacological and Supramolecular Applications
Authors: Virtanen Elina , Kolehmainen Erkki
Published: October 2004

For Abstract see ChemInform Abstract in Full Text.
Aquaporin Water Channels (Nobel Lecture)
Authors: Agre Peter
Published: October 2004

For Abstract see ChemInform Abstract in Full Text.
Chiral Bisphosphines and Their Industrial Application
Authors: Gerlach Arne , Scholz Ulrich
Published: October 2004

For Abstract see ChemInform Abstract in Full Text.
Polarization Measurements in Macro‐ and Micro‐Raman Spectroscopies: Molecular Orientations in Thin Films and Azo‐Dye Containing Polymer Systems
Authors: Sourisseau Claude
Published: October 2004

For Abstract see ChemInform Abstract in Full Text.
Structure Determination of Membrane Proteins by NMR Spectroscopy
Authors: Opella Stanley J. , Marassi Francesca M.
Published: October 2004

For Abstract see ChemInform Abstract in Full Text.
NMR Characterization of the Dynamics of Biomacromolecules
Authors: Palmer Arthur G. III
Published: October 2004

For Abstract see ChemInform Abstract in Full Text.
Proton MRS Can Determine the Pathology of Human Cancers with a High Level of Accuracy
Authors: Mountford Carolyn E. , Doran Sinead , Lean Cynthia L. , Russell Peter
Published: October 2004

For Abstract see ChemInform Abstract in Full Text.
Trends in the incidence of acquired immunodeficiency syndrome–related malignancies in Thailand
Authors: Sriplung Hutcha , Parkin D. Maxwell
Published: October 2004

BACKGROUND

Thailand was one of the first Asian countries to be affected by the epidemic of human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). Furthermore, Thailand possesses a national cancer surveillance system based upon regional cancer registries.

METHODS

Data from five population‐based cancer registries, covering one‐fifth of the national population, were used to study trends in the incidence of malignancies related to HIV/AIDS in Thailand during the period 1989–2001.

RESULTS

Although the incidence of Kaposi sarcoma (KS) increased slightly from 1989–1991 to 1995–1997, KS remains a very rare malignancy in Thailand compared with other countries in which the prevalence of HIV/AIDS is much lower. The authors reported a marked increase in the incidence of non‐Hodgkin lymphoma (NHL), and particularly high‐grade/diffuse NHL. However, the largest increases in incidence were noted among individuals age ≥ 55 years and in regions with a relatively low prevalence of HIV/AIDS.

CONCLUSIONS

The rarity of KS presumably reflected the low prevalence of the causative agent (i.e., KS‐associated herpesvirus) in the Thai population. The increasing incidence of NHL may be related to the AIDS epidemic, although a similar increase is observed in many countries worldwide and is not specifically linked to the HIV/AIDS epidemic. Cancer 2004. © 2004 American Cancer Society.
Treatment outcomes of three‐dimensional conformal radiotherapy for localized prostate carcinoma
Authors: McCloskey Susan A. , Ellerbroek Nancy A. , McCarthy Lauren , Malcolm Arnold W. , Tao May Lin , Wollman Robert C. , Rose Christopher M.
Published: October 2004

BACKGROUND

The current study documented the implementation of three‐dimensional conformal radiotherapy and assessed the tumor control and toxicity of such treatment in a large, multisite community practice.

METHODS

The authors retrospectively reviewed their first 222 consecutive patients with clinically localized (N0) prostate carcinoma treated with a 6‐field conformal technique from October 1993 through March 2000. Standardized target definitions, dose planning constraints, and gantry angles were utilized to develop the treatment plan. Patients were categorized by low, intermediate, and high risk. Low risk was defined as T1a–T2a disease, a Gleason score < 7, and prostate‐specific antigen (PSA) level ≤ 10.0 ng/mL (n = 47 [21%]). Intermediate risk was defined as T2b disease, a Gleason score > 6, or PSA level > 10.01 ng/mL (n = 60 [27%]). High risk was defined as 2 of the above risk factors or as T3 disease, a Gleason score > 7, or a PSA level > 20 (n = 115 [52%]). Biochemical disease recurrence was defined in accordance with the American Society for Therapeutic Radiology and Oncology definition. Urinary and bowel toxicity were graded using the Radiation Therapy Oncology Group morbidity scoring system.

RESULTS

The median follow‐up after radiotherapy for surviving patients was 47 months (range, 0–99 months). The 2 and 5‐year actuarial biochemical control rates for all patients were 84% and 78%, respectively. Using logistic regression analysis, lower dose (< 75.6 gray [Gy] vs. 75.6 Gy; P = 0.006), higher risk group (P = 0.033), higher stage (P = 0.045), and higher PSA level (P = 0.001) were significantly associated with biochemical disease recurrence. Toxicity was not significantly correlated with a higher radiotherapy dose.

CONCLUSIONS

Dose escalation to 75.6 Gy using a 6‐field conformal technique was feasible in the authors' community practice and resulted in acceptable toxicity and early biochemical outcomes. Cancer 2004. © 2004 American Cancer Society.
Defining the best available treatment for neurocytomas in children
Authors: Rades Dirk , Schild Steven E. , Fehlauer Fabian
Published: October 2004

BACKGROUND

In children, neurocytomas are extremely rare tumors in the central nervous system. Since this entity was introduced in 1982, approximately 60 cases have been reported among patients age ≤ =18 years of age. The current analysis was performed to define the best available neurocytoma therapy in children.

METHODS

All reported neurocytoma cases were reviewed for age, extent of resection, radiotherapy, radiotherapy dose, local control, and survival. Data were obtained from the literature and the authors. Statistical analysis was performed with the Kaplan–Meier method and log‐rank test.

RESULTS

Fifty‐nine children were categorized by therapy: complete tumor resection (CTR; n = 20), complete tumor resection plus radiotherapy (CTR‐RT; n = 11), incomplete tumor resection (ITR; n = 14), and incomplete tumor resection plus radiotherapy (ITR‐RT; n = 14). Local control rates were better after CTR, CTR‐RT, and ITR‐RT than after ITR, at 5 years (86%, 100%, and 100% vs. 60%; P < 0.001) and at 10 years (86%, 100%, and 100% vs. 45%; P < 0.001). The 5‐year and 10‐year survival rates were 100% after CTR, 100% after CTR‐RT, 100% after ITR‐RT, and 93% after ITR (P = 0.4). In the ITR‐RT group, no difference was observed between doses ≤ 50 gray (Gy) and ≥ 54 Gy when compared for local control (P = 1.0) and survival rates (P = 1.0). Radiotherapy‐related psychomotor retardation or secondary brain tumors were not reported.

CONCLUSIONS

The prognosis of children with neurocytomas is extremely good. CTR was associated with better local control and survival rates than ITR. After ITR, radiotherapy improves local control, but not survival. If postoperative radiotherapy is considered, a dose of 50 Gy was appropriate for long‐term local control in children, whereas higher doses were required in adults. Cancer 2004. © 2004 American Cancer Society.
Zur praktischen Anwendung der Lastkombinatorik bei Geschoßbauten aus Mauerwerk: Computergestützter Nachweis von Mauerwerk nach DIN 1053‐1 und EC 6
Authors: Purtak Frank
Published: October 2004

Im vorliegenden Beitrag werden für Geschoßbauten mit Mauerwerkswänden die zu untersuchenden Lastkombinationen unabhängig von der gewählten Berechnungsvorschrift dargestellt. Die maßgebenden Schnittkräfte resultieren aus zwei möglichen Lastzuständen der Decken – minimaler und maximaler Lastzustand. Je nach Wahl der Berechnungsvorschrift ergeben sich unterschiedliche Beträge der Lastzustände, welche je nach Vorschrift zu berücksichtigende Last‐ und Kombinationsfaktoren bereits enthalten. Maßgebende Lastkombinationen lassen sich daher leicht nachvollziehen und kontrollieren.

Der Berechnungsablauf nach DIN 1053‐1 und EC 6 ist in kompakter Form tabellarisch zusammengestellt. Das zur Verfügung stehende Computerprogramm beinhaltet den dargestellten Berechnungsablauf und unterstützt die statischen Nachweise für beide Normen.
Digitales Bearbeitungskonzept für die Statik
Authors: Christoph Veit
Published: October 2004

Die Computertechnik und insbesondere das Internet entwickeln sich rasant. Im Beitrag werden Entwicklungstendenzen und deren Auswirkungen auf die Arbeit des Tragwerksplaners aufgezeigt. Am Beispiel einer durchgehenden Lösung im Mauerwerksbau werden neue Techniken erläutert. Der Beitrag zeigt Anwendungen, die bereits verfügbar sind und ordnet diese in bezug auf ihren zukünftigen Stellenwert ein.
Druckfestigkeit von Mauerwerk parallel zu den Lagerfugen
Authors: Schubert Peter , Graubohm Markus
Published: October 2004

Druckfestigkeit von Mauerwerk parallel zu den Lagerfugen
Die Druckfestigkeit von Mauerwerk parallel zu den Lagerfugen – auch Längsdruckfestigkeit genannt – wird für Tragfähigkeitsnachweise für Mauerwerkbauteile, die parallel zu den Lagerfugen auf Biegedruck beansprucht werden, benötigt. Von wesentlichem Einfluß auf die Längsdruckfestigkeit von Mauerwerk sind die Längsdruckfestigkeit der Mauersteine und die Art der Stoßfugenausführung (vermörtelt, unvermörtelt) sowie im Falle der unvermörtelten Stoßfugen die Verbundfestigkeit zwischen Mauerstein und Mauermörtel in der Lagerfuge. Im Beitrag werden alle vorliegenden Untersuchungsergebnisse zur Längsdruckfestigkeit von Mauerwerk mit den wesentlichen Kennwerten zusammengestellt, ausgewertet und bewertet sowie erste Vorschläge für die Berücksichtigung der Längsdruckfestigkeit von Mauerwerk bei der Bemessung gemacht.
Druckfestigkeit und E‐Modul von Dünnbettmauerwerk – Teil 1: Dünnbettmauerwerk aus Porenbeton‐Plansteinen
Authors: Schubert Peter , Beer Ingo , Graubohm Markus
Published: October 2004

Der Erkenntnisstand und die Datenbasis für Eigenschaftswerte von Mauersteinen, Mauermörtel und Mauerwerk, die DIN 1053‐1 [1] zugrunde liegen, sind rd. 10 Jahre alt. Für die derzeitige Überarbeitung der DIN müssen die entsprechenden Eigenschaftskennwerte unter Bezug auf die zwischenzeitliche Weiterentwicklung des Mauerwerks und die fortgeschriebenen Untersuchungen aktualisiert werden.

Alle verfügbaren und verwertbaren Untersuchungsergebnisse zur Druckfestigkeit von Dünnbettmauerwerk aus Porenbeton‐Plansteinen wurden in einer Datenbank erfaßt und hinsichtlich weiterer wichtiger Kennwerte ausgewertet.

Danach kann die Mauerwerkdruckfestigkeit sowohl unter Bezug auf den Mittelwert als auch bezogen auf den charakteristischen Wert ausreichend genau in Abhängigkeit von der Druckfestigkeit der Plansteine bzw. von Würfeln mit 100 mm Kantenlänge rechnerisch beschrieben werden. Die entsprechenden Regressionsgleichungen sind mit dem jeweiligen Bestimmtheitsmaß angegeben und in den Diagrammen zusammen mit den Versuchswerten dargestellt.
Mechanism of modulation of T cell responses by N‐palmitoylated peptides
Authors: Bueno Clara , Lee Kenneth K. , Chau Luan A. , Lee‐Chan Edwin , Singh Bhagirath , Strejan Gill H. , Madrenas Joaquín
Published: October 2004

Small structural changes in the antigenic peptides recognized by TCR can alter the biological properties of those peptides and convert them into weak agonists, partial agonists, or antagonists of these receptors. These altered peptide ligands (APL) are usually generated by conservative amino acid substitutions at TCR contact residues. Here, we show that APL with therapeutic properties can also be generated by attachment of palmitic acid at the N terminus of the peptide without the need to modify the peptide's primary sequence. Using N‐palmitoylated pigeon cytochrome‐c peptide 81–104 (PALPCC81–104), we were able to induce T cell hyporesponsiveness to the wild‐type peptide in vitro. More importantly, administration of the PALPCC81–104 to mice reduced the responsiveness to the native peptide when tested ex vivo. Biochemical and functional experiments indicated that the action of N‐palmitoylated peptides was due to the conversion of the native peptide into a weak agonist that could then induce T cell anergy. Our results demonstrate that N‐palmitoylation of antigenic peptides is a feasible strategy to generate APL, as it avoids the need to screen multiple amino acid variants of each specific antigen to identify those with therapeutic properties.
Syntheses, Structures and Reactivity of Electron‐Rich Fe and Ru Complexes with the New Pentadentate Ligand Et2NpyS4−H2 {4‐(Diethylamino)2,6‐bis[(2‐mercaptophenyl)thiomethyl]pyridine}
Authors: Sellmann Dieter , Shaban Shaban Y. , Heinemann Frank W.
Published: October 2004

The new pentadentate thioether thiolate ligand Et2NpyS42− {= 4‐(diethylamino)‐2,6‐bis[(2‐mercaptophenyl)thiomethyl]pyridine(2−)} has been synthesised from dimethyl 4‐bromopyridine‐2,6‐dicarboxylate by treatment with Et2NH followed by reduction and tosylation. The tosylated product was subsequently used for the template alkylation of [Ni(S2C6H4)2]2− to give [{Ni(Et2NpyS4)}2] (4). Acidic hydrolysis of 4 resulted in the formation of the ligand Et2NpyS4−H2·HCl (5). The dianion Et2NpyS42− reacted with FeCl2·H2O to afford the dinuclear high‐spin species [{Fe(Et2NpyS4)}2] (6) [μeff (297 K) = 5.15 μB]. Aerial oxidation of dinuclear 6 afforded the sulfinato complex [{Fe(Et2NpyS4−O2)}2] (7). Complex 6 proved to be a good precursor for the syntheses of [Fe(L)(Et2NpyS4)] [L = CO (8), CNCy (9), NO (11) and N2H4 (12)] and [Fe(NO)(Et2NpyS4)]BF4 (10). Protonation or alkylation of the thiolate donor atoms resulted in a series of complexes [Fe(CO)(Et2NpyS4−R)]BF4 [R = H (8a), Et (8b)] and [Fe(CO)(Et2NpyS4−Et2)](BF4)2 (8c) but no labilisation of the Fe−CO bond was observed. Only in complex 8 could the CO coligand be exchanged by NO+ to give [Fe(NO)(Et2NpyS4)]BF4 (10). Reduction of 10 using N2H4, NH3 or N3− afforded the 19 valence electron species [Fe(NO)(Et2NpyS4)] (11). [Ru(NO)(Et2NpyS4)]Br (13) was synthesised by template alkylation of Bu4N[Ru(NO)(S2C6H4)2] using Et2Npy(CH2Br)2 (3). Under reducing conditions, 13 releases the NO coligand to give [{Ru(Et2NpyS4)}2] (14), while in the presence of N2H4, [Ru(N2H4)(Et2NpyS4)] (15) was formed. The complexes were well characterised including the solid‐state structures in most cases. X‐ray structural analyses of 7, 8, 9, 10, 12 and 15 revealed that all complexes exhibit trans‐thiolate donors irrespective of the σ−π‐ or σ‐ligand character of L. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Synthesis, Structure and Properties of a Mononuclear and an End‐On Double Azido‐Bridged Copper(II) Complex Incorporating an N,N,N,O‐Coordinating Tripodal Ligand
Authors: Sarkar Sumana , Mondal Amrita , Ribas Joan , Drew M. G. B. , Pramanik Kausikisankar , Rajak Kajal Krishna
Published: October 2004

The blue coloured complex [Cu(HL)(H2O)(ClO4)]ClO4·H2O·MeOH (1·H2O·MeOH) has been synthesised in excellent yields by reacting Cu(ClO4)2·6H2O with N,N‐bis(2‐methylpyridyl)(3,5‐dimethyl‐2‐hydroxybenzyl)amine (HL) in methanol. The same reaction, when carried out in the presence of sodium azide, afforded a dark‐blue complex of formula [Cu2(HL)2(μ‐1,1‐N3)2](ClO4)2 (2). The crystal and molecular structures of the complexes have been solved. Variable‐temperature magnetic susceptibility data in the range of 2−300 K for 2 reveal the existence of an antiferromagnetic interaction through an end‐on azido linker. Temperature‐dependent susceptibility studies for 2 were fitted using the Bleaney−Bowers expression, which led to the parameters J = −3.2 cm−1, g = 2.12 and R = 2.14 × 10−4. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Slow Electron Self‐Exchange in Spite of a Small Inner‐Sphere Reorganisation Energy − The Electron‐Transfer Properties of a Copper Complex with a Tetradentate Bispidine Ligand
Authors: Comba Peter , Kerscher Marion , Roodt Andreas
Published: October 2004

The electron self‐exchange rate of [Cu(L)(OH2)]2+/1+, kexp11 (298.13 K) = 15 ± 11 m−1s−1 {L = dimethyl 3,7‐dimethyl‐9oxo‐2,4‐bis(2‐pyridyl)‐3,7‐diazabicyclo[3.3.1]nonane‐1,5‐dicarboxylate}, was determined by a cross reaction. The analysis, based on classical Marcus theory, indicates that this relatively slow rate is to a large extent due to enthalpic terms (ΔG‡,exp11 = 62.8 ± 3.5 kJ·mol−1, ΔH‡,exp11 = 36.0 ± 2.7 kJ·mol−1 and ΔS‡,exp11 = −92 ± 10 J·mol−1K−1). The activation entropy is significant but not unusually large and the calculated outer‐sphere reorganization energy, ΔG*,calcout = 20.5 kJ·mol−1, is at least of the same order of magnitude as the calculated inner‐sphere reorganisation energy ΔG*,calcin = 18.6 kJ·mol−1, i.e. the deformation of the solvent sheath is a major reason for the slow electron transfer rate. This is believed to be due to the highly elastic coordination geometry which leads to little strain upon distortion enforced by the electron transfer but to comparably large structural changes and, hence, to a large outer‐sphere reorganisation term. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Single‐Walled Carbon Nanotubes on Tungsten Wires: A New Class of Microelectrochemical Sensors
Authors: Valentini F. , Orlanducci S. , Tamburri E. , Terranova M. L. , Curulli A. , Palleschi G.
Published: October 2004

This paper reports the fabrication and the outstanding performance characteristics of novel microelectrodes consisting of tungsten (W) wires coated with homogeneous layers of single‐walled C nanotubes (SWNT). A series of studies using cyclic voltammetry indicate that the SWNT‐modified W electrodes possess interesting electrochemical features. In fact, they are able to catalyse electron transfer reactions involving a series of inorganic and biological molecules. These electrodes are characterized by a fast electron transfer, a wide working potential window, and a low background current. Moreover they demonstrate excellent reproducibility, good stability in various chemical media, and very high sensitivity towards a series of inorganic and organic compounds. The SWNT modified microelectrodes have been tested for the capacity to electrochemically detect ferrocene monocarboxylic acid and potassium hexacyanoferrate as well of a series of interesting biological molecules which include catechol, caffeic acid, DOPAC, ascorbic acid, L‐tyrosine, acetaminophen, guanine, uric acid, and the neurotransmitters dopamine, epinephrine, and serotonin (5‐HT) hydrochloride. The advantages of the SWNT‐modified W electrodes are illustrated by comparing their analytical performance with that of conventional electrodes.
Contactless Conductivity Detection in Capillary Electrophoresis: A Review
Authors: Kubáň Pavel , Hauser Peter C.
Published: October 2004

The popularity of contactless conductivity detection in capillary electrophoresis has been growing steadily over the last few years. Improvements have been made in the design of the detector in order to facilitate its handling, to allow easy incorporation into available instruments or to achieve higher sensitivity. The understanding of its fundamental working principles has been advanced and the detection approach has also been transferred to lab‐on‐chip devices. The range of applications has been extended greatly from the initial work on small inorganic ions to include organic species and biomolecules. Concurrent determination of cations and anions by dual injection from opposite ends has been demonstrated as well as sample introduction by using flow‐injection systems for easy automation of the process.
Finite element methods based on a new formulation for the non‐stationary incompressible Navier–Stokes equations
Authors: Lin Ping , Chen Xianqiao , Ong Ming Tze
Published: October 2004

A new formulation of the Navier–Stokes equations is introduced to solve incompressible flow problems. When finite element methods are used under this formulation there is no need to worry whether Babuska–Brezzi condition is satisfied or not. Both velocity and pressure can be obtained separately and the pressure can be simply obtained by a substitution. Moreover, fully explicit time integration can be applied for easy implementation. Implementation issues are discussed and a couple of flow examples are simulated. Parallel implementation based on domain decomposition is incorporated as well. Copyright © 2004 John Wiley & Sons, Ltd.
Frequent deletions at 12q14.3 chromosomal locus in adult acute lymphoblastic leukemia
Authors: Patel Hemantkumar S. , Kantarjian Hagop M. , Bueso‐Ramos Carlos E. , Medeiros L. Jeffrey , Haidar Mohammad A.
Published: October 2004

Cytogenetic abnormalities at the 12q12‐q14 chromosomal locus are rarely detected in acute lymphoblastic leukemia (ALL). To examine submicroscopic deletions at this locus, we analyzed 78 adult precursor B‐ and T‐cell ALL cases [27 with Philadelphia chromosome (Ph)–negative B‐cell ALL, 20 with Ph‐negative B‐cell ALL with expression of one or two myeloid markers, 18 with Ph‐positive B‐cell ALL, and 13 with T‐cell ALL] using a panel of 13 microsatellite (MST) markers that span the 12q12–q14.3 region. The status of MST markers was evaluated by use of polymerase chain reaction performed with fluorescence‐labeled primers and automated fragment analysis. The MST marker analyses showed submicroscopic deletions at the 12q14.3 locus in 20 of the 78 ALL cases (26%). The frequency of deletions was highest in Ph‐negative B‐cell ALL (13 of 27, 48%) compared with that in Ph‐negative B‐cell ALL with expression of myeloid markers (4 of 20, 20%), Ph‐positive B‐cell ALL (2 of 18, 11%), and T‐cell ALL (1 of 13, 8%). Deletion frequencies of MST markers along the 12q12–q14.3 locus suggest that the targeted gene of deletion is located within a 170‐kb region bordered by the markers D12S1504 (approximately 65 kb upstream of HMGA2) and D12S1509 (in intron 3 of HMGA2) at the 12q14.3 locus. These submicroscopic deletions at the 12q14.3 locus may play a role in the pathogenesis of ALL, particularly in Ph‐negative precursor B‐cell ALL. © 2004 Wiley‐Liss, Inc.
Drosophila tudor is essential for polar granule assembly and pole cell specification, but not for posterior patterning
Authors: Thomson Travis , Lasko Paul
Published: October 2004

Pole cells and posterior segmentation in Drosophila are specified by maternally encoded genes whose products accumulate at the posterior pole of the oocyte. Among these genes is tudor (tud). Progeny of hypomorphic tud mothers lack pole cells and have variable posterior patterning defects. We have isolated a null allele to further investigate tud function. While no pole cells are ever observed in embryos from tud‐null mothers, 15% of these embryos have normal posterior patterning. OSKAR (OSK) and VASA (VAS) proteins, and nanos (nos) RNA, all initially localize to the pole plasm of tud‐null oocytes and embryos from tud‐null mothers, while localization of germ cell‐less (gcl) and polar granule component (pgc), is undetectable or severely reduced. In embryos from tud‐null mothers, polar granules are greatly reduced in number, size, and electron density. Thus, tud is dispensable for somatic patterning, but essential for pole cell specification and polar granule formation. genesis 40:164–170, 2004. © 2004 Wiley‐Liss, Inc.
Estimating mean QALYs in trial‐based cost‐effectiveness analysis: the importance of controlling for baseline utility
Authors: Manca Andrea , Hawkins Neil , Sculpher Mark J.
Published: October 2004

In trial‐based cost‐effectiveness analysis baseline mean utility values are invariably imbalanced between treatment arms. A patient's baseline utility is likely to be highly correlated with their quality‐adjusted life‐years (QALYs) over the follow‐up period, not least because it typically contributes to the QALY calculation. Therefore, imbalance in baseline utility needs to be accounted for in the estimation of mean differential QALYs, and failure to control for this imbalance can result in a misleading incremental cost‐effectiveness ratio. This paper discusses the approaches that have been used in the cost‐effectiveness literature to estimate absolute and differential mean QALYs alongside randomised trials, and illustrates the implications of baseline mean utility imbalance for QALY calculation. Using data from a recently conducted trial‐based cost‐effectiveness study and a micro‐simulation exercise, the relative performance of alternative estimators is compared, showing that widely used methods to calculate differential QALYs provide incorrect results in the presence of baseline mean utility imbalance regardless of whether these differences are formally statistically significant. It is demonstrated that multiple regression methods can be usefully applied to generate appropriate estimates of differential mean QALYs and an associated measure of sampling variability, while controlling for differences in baseline mean utility between treatment arms in the trial. Copyright © 2004 John Wiley & Sons, Ltd.
Elemental distributions and microtensile bond strength of the adhesive interface to normal and caries‐affected dentin
Authors: Nakajima Masatoshi , Kitasako Yuichi , Okuda Mamiko , Foxton Richard M. , Tagami Junji
Published: October 2004

The aim of this study was to evaluate the microtensile bond strength (μTBS) and the elemental contents of the adhesive interface created to normal versus caries‐affected dentin. Extracted human molars with coronal carious lesions were used in this study. A self‐etching primer/adhesive system (Clearfil Protect Bond) was applied to flat dentin surfaces with normal and caries‐affected dentin according to the manufacturer's instructions. After 24 h water storage, the bonded specimens were cross‐sectioned and subjected to a μTBS test and electron probe microanalysis for the elemental distributions [calcium (Ca), phosphorus (P), magnesium (Mg), and nitrogen (N)] of the resin–dentin interface after gold sputter‐coating. The μTBS to caries‐affected dentin was lower than that of normal dentin. The demineralized zone of the caries‐affected dentin–resin interface was thicker than that of normal dentin (approximately 3 μm thick in normal dentin; 8 μm thick in caries‐affected dentin), and Ca and P in both types of dentin gradually increased from the interface to the underlying dentin. The caries‐affected dentin had lost most of its Mg content. The distributions of the minerals, Ca, P, and Mg, at the adhesive interface to caries‐affected dentin were different from normal dentin. Moreover, a N peak, which was considered to be the collagen‐rich zone resulting from incomplete resin infiltration of exposed collagen, was observed to be thicker within the demineralized zone of caries‐affected dentin compared with normal dentin. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 72B: 268–275, 2005
Zirconia to Ti‐6Al‐4V braze joint for implantable biomedical device
Authors: Jiang Guangqiang , Mishler Delta , Davis Ross , Mobley Jon Phil , Schulman Joseph H.
Published: October 2004

A strong, hermetic, reliable, and biocompatible ceramic‐to‐metal seal is essential for many implantable medical devices. Yttria‐stabilized tetragonal zirconia polycrystals (Y‐TZPs) and a titanium alloy Ti‐6Al‐4V were selected as the ceramic and metal components of the seal because both materials have excellent mechanical properties and favorable biocompatibility. A brazing method using titanium nickel (TiNi)‐clad braze filler material is presented to bond the components together forming a seal. Laboratory tests show that the ceramic‐to‐metal seal is hermetic, strong, and resistant to electrochemical corrosion. Twenty‐eight microstimulators utilizing the ceramic‐to‐metal seals were implanted in seven sheep to stimulate the hypoglossal nerve. When the tissue was evaluated by gross inspection at necropsy and examined histologically by a pathologist, there were no signs of local hemorrhage, infection, or hypoglossal nerve tissue damage. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 72B: 316–321, 2005
Hepatic tissue engineering for adjunct and temporary liver support: Critical technologies
Authors: Chan Christina , Berthiaume François , Nath Bharath D. , Tilles Arno W. , Toner Mehmet , Yarmush Martin L.
Published: October 2004

The severe donor liver shortage, high cost, and complexity of orthotopic liver transplantation have prompted the search for alternative treatment strategies for end-stage liver disease, which would require less donor material, be cheaper, and less invasive. Hepatic tissue engineering encompasses several approaches to develop adjunct internal liver support methods, such as hepatocyte transplantation and implantable hepatocyte-based devices, as well as temporary extracorporeal liver support techniques, such as bioartificial liver assist devices. Many tissue engineered liver support systems have passed the “proof of principle” test in preclinical and clinical studies; however, they have not yet been found sufficiently reliably effective for routine clinical use. In this review we describe, from an engineering perspective, the progress and remaining challenges that must be resolved in order to develop the next generation of implantable and extracorporeal devices for adjunct or temporary liver assist. (Liver Transpl 2004;10:1331-1342.)
Outcomes in liver transplant recipients with hepatitis B virus: Resistance and recurrence patterns from a large transplant center over the last decade
Authors: Neff Guy W. , O’Brien Christopher B. , Nery Jose , Shire Norah , Montalbano Marzia , Ruiz Phillip , Nery Ciao , Safdar Kamran , De Medina Maria , Tzakis Andreas G. , Schiff Eugene R. , Madariaga Juan
Published: October 2004

Hepatitis B virus (HBV) recurrence following liver transplantation (LTx) has been controllable primarily with the use of hepatitis B immune globulin (HBIg) and lamivudine (LAM). However, HBV resistance to LAM and/or HBIg has become an increasing problem prompting the use of newer antiviral agents. The purpose of our study was to investigate the association between therapy, HBV breakthrough, and allograft / patient survival in HBV-positive liver transplant recipients. We performed a retrospective review of the medical records of patients that were transplanted for HBV from June 1994 to May 2003. A total of 92 patients, positive for either hepatitis B surface antigen (HBsAg) or HBV deoxyribonucleic acid (DNA) pretransplant, received LAM monotherapy or HBIg (6 months) plus LAM therapy post-liver transplant. HBV breakthrough post-LTx was noted in 14 patients. All patients had detectable HBV DNA prior to liver transplantation; none of the patients that were HBV DNA negative prior to transplant had detectable HBV DNA posttransplant. Of these 14, 9 patients (64%) were switched from LAM to adefovir dipivoxil (ADF) and 5 patients (36%) to tenofovir disoproxil fumarate (TNV). In conclusion, pre-LTx HBV viremia should be considered in planning post-LTx prophylaxis. Trials to evaluate oral antiviral agents in combination with or without HBIg therapy are needed. (Liver Transpl 2004;10:1372-1378.)
Thermosensitivity of Optically Active Hydrogels Constructed with N‐(L)‐(1‐hydroxymethyl)propylmethacrylamide
Authors: Aoki Takashi , Muramatsu Mika , Nishina Akino , Sanui Kohei , Ogata Naoya
Published: October 2004

Summary: We previously reported on the water soluble, optically active polymer, poly[N‐(L)‐(1‐hydroxymethyl)propylmethacrylamide] (P(L‐HMPMA)), which has lower critical solution temperatures of approximately 30 and 21 °C upon heating and cooling, respectively. The phase separation behavior of the P(L‐HMPMA)‐water binary system has a reversible and clear hysteresis during heating and cooling cycles. The present study describes the thermosensitive properties of the optically active polymer and its hydrogel. Circular dichroism and microcalorimetric measurements of the polymer in water supported the hypothesis that the soluble polymer chains might be compactly folded with an interaction between optically active side chains. In addition, these measurements showed the polymer chains in a state of relatively low hydration compared to that of P(D,L‐HMPMA), which was free‐radically synthesized from racemates of monomers. The solution properties reflected the swollen‐shrunken behavior of corresponding hydrogels in response to temperature changes. The microscopic observation of aqueous polymer solutions and hydrogels also confirmed that the optically active properties of polymer chains affect their structure and thermosensitivity.

SEM micrograph of the surfaces of the crosslinked P(L‐HMPMA).

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SEM micrograph of the surfaces of the crosslinked P(L‐HMPMA).
Critically Evaluated Rate Coefficients for Free‐Radical Polymerization, 5,
Authors: Asua José M. , Beuermann Sabine , Buback Michael , Castignolles Patrice , Charleux Bernadette , Gilbert Robert G. , Hutchinson Robin A. , Leiza José R. , Nikitin Anatoly N. , Vairon Jean‐Pierre , van Herk Alex M.
Published: October 2004

Summary: Propagation rate coefficients, kp, for free‐radical polymerization of butyl acrylate (BA) previously reported by several groups are critically evaluated. All data were determined by the combination of pulsed‐laser polymerization (PLP) and subsequent polymer analysis by size exclusion (SEC) chromatography. The PLP‐SEC technique has been recommended as the method of choice for the determination of kp by the IUPAC Working Party on Modeling of Polymerization Kinetics and Processes. Application of the technique to acrylates has proven to be very difficult and, along with other experimental evidence, has led to the conclusion that acrylate chain‐growth kinetics are complicated by intramolecular transfer (backbiting) events to form a mid‐chain radical structure of lower reactivity. These mechanisms have a significant effect on acrylate polymerization rate even at low temperatures, and have limited the PLP‐SEC determination of kp of chain‐end radicals to low temperatures (<20 °C) using high pulse repetition rates. Nonetheless, the values for BA from six different laboratories, determined at ambient pressure in the temperature range of −65 to 20 °C mostly for bulk monomer with few data in solution, fulfill consistency criteria and show excellent agreement, and are therefore combined together into a benchmark data set. The data are fitted well by an Arrhenius relation resulting in a pre‐exponential factor of 2.21 × 107 L · mol−1 · s−1 and an activation energy of 17.9 kJ · mol−1. It must be emphasized that these PLP‐determined kp values are for monomer addition to a chain‐end radical and that, even at low temperatures, it is necessary to consider the presence of two radical structures that have very different reactivity. Studies for other alkyl acrylates do not provide sufficient results to construct benchmark data sets, but indicate that the family behavior previously documented for alkyl methacrylates also holds true within the alkyl acrylate family of monomers.

Arrhenius plot of propagation rate coefficients, kp, for BA as measured by PLP‐SEC.

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Arrhenius plot of propagation rate coefficients, kp, for BA as measured by PLP‐SEC.
Advancing from subjective to confirmatory personal introspection in consumer research
Authors: Woodside Arch G.
Published: October 2004

Research findings support the view that a multiple‐methods approach is necessary to surface the substantial amount of relevant thinking processes that occur both consciously and unconsciously within different phases of consumer decision making. This article advocates viewing all studies that ask informants questions as representative of researcher–informant introspections. Because answers to questions differ substantially depending on how the questions are framed, applying multiple, explicit, question frames to acquire conscious and unconscious thoughts in researcher–informant introspections is helpful. This article reviews multiple methods, including metaphor elicitation of unconscious thinking, useful for achieving and confirming thick descriptions of conscious and unconscious thinking associated with informants' deep‐seated beliefs and observable actions. © 2004 Wiley Periodicals, Inc.
Exploring the role of memory for self‐selected ad experiences: Are some advertising media better liked than others?
Authors: Shavitt Sharon , Vargas Patrick , Lowrey Pamela
Published: October 2004

Advertising media are associated with different degrees of self‐selected versus intrusive ad experiences. The role of such media differences in attitudes toward advertising was explored in a nationwide survey. The survey provides a national picture of attitudes toward specific ad media ranging from advertising media that deliver highly self‐selected ad experiences (catalogs and business classifieds) to highly intrusive ones (TV). A total of 2,514 adults were surveyed regarding their opinions about ads in (1) TV, (2) radio, (3) catalogs, (4) business classifieds, (5) out‐of‐home, or (6) advertising in general. Media that allow for self‐selected experiences, where perceived interest in an ad is the basis for attention to it, were evaluated much more favorably than more intrusive advertising media. Catalogs and business classifieds elicited the most favorable opinions; TV advertising elicited the least, and these media differences generally cut across demographic lines. Also, although more educated and affluent consumers generally held less favorable views of advertising, preliminary results suggested that this did not hold true for media that allow for self‐selected processing. An additional study suggested that memory for advertisements plays a significant role in the evaluation of a self‐selected ad medium (catalogs). That is, consumers' strongest memories are for those ads to which they paid the most attention, and consequently these engaging ads have a disproportionate influence on opinions toward the ad medium. © 2004 Wiley Periodicals, Inc.
An approximate method for evaluating the shear band thickness in saturated soils
Authors: Lu X. B. , Shuyun Wang , Yihua Wang , Cui Peng
Published: October 2004

A formula for the thickness of a shear band formed in saturated soils under a simple shear or a combined stress state has been proposed. It is shown that the shear band thickness is dependent on the pore pressure properties of the material and the dilatancy rate, but is independent of the details of the combined stress state. This is in accordance with some separate experimental observations. Copyright © 2004 John Wiley & Sons, Ltd.
Mechanical behaviour and failure of cohesive granular materials
Authors: Delenne Jean‐Yves , El Youssoufi Moulay Saïd , Cherblanc Fabien , Bénet Jean‐Claude
Published: October 2004

We investigate the stress–strain behaviour and failure of a cohesive granular material both by experiments and numerical simulations. The material is an assembly of aluminium rods glued together by means of an epoxy resin. The behaviour of cohesive bonds (force–displacement relationship, failure conditions) is characterized by performing simple loading tests (tension/compression, shear…) on a couple of rods. Then, this local behaviour is introduced in a numerical code based on a discrete element method in order to perform numerical compression tests on large samples. The validation of this approach was the main goal of the present investigation that is essentially achieved by a direct comparison between the numerical results and similar experimental tests. As a basic application, we derive the macroscopic cohesion and friction characteristics of random cohesive materials by systematic numerical simulations in a biaxial geometry. Copyright © 2004 John Wiley & Sons, Ltd.
Entwicklung der Beta‐Blocker: Ein historischer Rückblick
Authors: Hein Lutz
Published: October 2004

Ein wesentlicher Meilenstein der Forschung, der den Weg für die Entwicklung von β‐Blockern bereitete, war die funktionelle Beschreibung von α‐ und β‐Rezeptoren. Raymond Ahlquist stellte 1948 die Hypothese auf, dass die verschiedenen biologischen Effekte der endogenen Katecholamine Adrenalin und Noradrenalin durch zwei verschiedene Typen von Rezeptoren, nämlich α‐ und β‐Rezeptoren vermittelt werden.
Klinischer Einsatz von Beta‐Blockern bei kardiovaskulären Indikationen: Neue Therapiestudien
Authors: Maack Christoph , Böhm Michael
Published: October 2004

β‐Adrenozeptor‐ (β‐AR‐)Antagonisten (β‐Blocker) haben seit langem einen festen Platz in der Behandlung der arteriellen Hypertonie (Primärprävention) sowie der koronaren Herzkrankheit, insbesondere nach einem Myokardinfarkt (Sekundärprävention). Erst seit wenigen Jahren sind die β‐Blocker Carvedilol, Bisoprolol und Metoprolol auch zur Behandlung der chronischen Herzinsuffizienz zugelassen.
Pharmakoökonomische Überlegungen zu Beta‐Blockern: Wirtschaftliche Therapie‐Aspekte
Authors: Lemmer Björn
Published: October 2004

Der GKV‐Arzneimittelumsatz im Jahre 2002 betrug 22,7 Mrd. Euro, dabei war ein Anstieg von 6,5 % gegenüber dem Vorjahr festzustellen. Unter den 20 führenden Indikationsgruppen, die etwa 77 % der gesamten Verordnungen und 70 % des Umsatzvolumens ausmachen, lag an Stelle 2 die Gruppe der β‐Adrenozeptor‐Antagonisten/Calcium‐Kanal‐Blocker/Angiotensin‐Rezeptor‐Antagonisten [1a]. Damit stellen diese kardiovaskulär wirksamen Pharmaka einen bedeutsamen Anteil an den Arzneimittelkosten dar. An dieser Stelle soll auf die Gruppe der β‐Adrenozeptor‐Antagonisten (β‐Blocker) näher eingegangen werden.
Ursache des Muskelschwunds geklärt?
Authors: Dingermann Theo , Zündorf Ilse
Published: October 2004

So ganz en passant konnte die Gruppe um Ralf Baumeister in Freiburg auf der Suche nach der Entstehungsursache des Morbus Parkinson auch den Mechanismus für Auf‐ und Abbau der Muskulatur aufklären.
Das Springkraut – Von explosiver Ungeduld
Authors: Junghans Thomas
Published: October 2004

Von den vier Vertretern der Springkrautgewächse (Balsaminaceae) sind drei monotypisch, d.h. sie bestehen nur aus einer einzigen Art, so dass die etwa 600 Arten der Familie fast vollständig auf das Springkraut selbst (Gattung Impatiens) entfallen.
Processing of ultra‐high molecular weight polyethylene by hot isostatic pressing, and the effect of processing parameters on its microstructure
Authors: Gul Rizwan M. , McGarry Frederick J.
Published: October 2004

The processing techniques available for ultra‐high molecular weight polyethylene (UHMWPE) do not lead to a homogeneous material. The processed material exhibits particle boundaries (fusion defects) reflecting the powder flakes of the virgin resin. Hot isostatic pressing has been used in this study as a possible technique to produce a homogeneous, defect‐free material, and to study the effect of processing parameters on consolidation and other properties. The extent of consolidation was determined by optical microscopy using thin sections, and by scanning electron microscopy using cryofractured and solvent‐etched specimens. Processing temperature is the most important variable affecting consolidation; fusion defects can be eliminated by increasing the processing temperature. This is sometimes accompanied by the appearance of spherulties; however, the degree of crystallinity, melting point, and density remain constant. DMA results show that the molecular weight between entanglements increases and the entanglement structure changes with an increase in processing temperature. Polym. Eng. Sci. 44:1848–1857, 2004. © 2004 Society of Plastics Engineers.
A temperature‐dependent adaptive controller. Part I: Controller methodology and open‐loop testing
Authors: Dubay Rickey , Lakhram Rodney
Published: October 2004

Currently, the controllers for achieving a desired injection velocity setpoint profile are independent of processing conditions in plastic injection molding. The dynamics of the reciprocating screw during injection mold filling is complex and temperature‐dependent. This complexity is based on process parameters that are nonlinear, which can vary spatially in time. Open‐loop tests were performed on two polymers at three melt temperatures and three mold‐fill velocity regimes: low, medium, and high. These tests were based on close‐loop injection mold‐fill setpoints and a derived voltage velocity relationship for the injection velocity hydraulic valve. The results of the open‐loop tests show that mold‐filling injection velocity is polymer‐ and melt temperature‐dependent. Polym. Eng. Sci. 44:1925–1933, 2004. © 2004 Society of Plastics Engineers.
A parallel coextrusion technique for simultaneous measurements of radial die swell and velocity profiles of a polymer melt in a capillary rheometer
Authors: Intawong N.‐T. , Sombatsompop N.
Published: October 2004

This article proposes a new experimental technique to simultaneously measure radial die swell and velocity profiles of polystyrene melt flowing in the capillary die of a constant shear rate rheometer. The proposed technique was based on parallel coextrusion of colored melt‐layers into uncolored melt‐stream from the barrel into and out of the capillary die. The size (thickness) ratio of the generated melt layers flowing in and out of the die was monitored to produce the extrudate swell ratio for any given radial position across the die diameter. The radial velocity profiles of the melt were measured by introducing relatively light and small particles into the melt layers, and the times taken for the particles to travel for a given distance were measured. The proposed experimental technique was found to be both very simple and useful for the simultaneous and accurate measurement of radial die swell and velocity profiles of highly viscous fluids in an extrusion process. The variations in radial die swell profiles were explained in terms of changes in melt velocity, shear rate, and residence time at radial positions across the die. The radial die swell and velocity profiles for PS melt determined experimentally in this work were accurate to 92.2% and 90.8%, respectively. The overall die swell ratio of the melt ranged from 1.25 to 1.38. The overall die swell ratio was found to increase with increasing piston speed (shear rate). The radial extrudate swell profiles could not be reasoned by the shear rate change, but were closely linked with the development of the velocity profiles of the melt in the die. The die swell ratio was high at the center (∼1.9) and low (∼0.9) near the die wall. The die swell ratio at the center of the die reduced slightly as the piston speed was increased. Polym. Eng. Sci. 44:1960–1969, 2004. © 2004 Society of Plastics Engineers.