bluuebunny/crossref_metadata_2025 huggingface dataset:
Cover Picture: On‐Bead Chemical Synthesis and Display of Phosphopeptides for Affinity Pull‐Down Proteomics (ChemBioChem 4/2006)
Authors: Brandt Malene , Madsen Jens C. , Bunkenborg Jakob , Jensen Ole N. , Gammeltoft Steen , Jensen Knud J.
Published: March 2006

The cover picture shows how a polymer bead travels through chemistry space from chemical synthesis of its phosphopeptide ligands to use in the affinity pull‐down of 14‐3‐3 proteins. First a phosphopeptide is synthesized on a PEGA support, next the phosphopeptide ligands selectively bind 14‐3‐3 proteins from cell lysates, finally the proteins are released for proteomic analysis and identification by mass spectrometry. Peptide sequences containing two phosphorylation motifs of the proapoptotic protein Bad were used as baits in affinity pull‐down experiments to determine their ability to bind intracellular 14‐3‐3 proteins. The support‐bound Bad phosphopeptides were able to pull‐down 14‐3‐3 proteins from cell lysates, and all seven members of the 14‐3‐3 family were identified by mass spectrometry. More about this fast and efficient on‐bead method for affinity pull‐down proteomics is reported by K. J. Jensen et al. on p. 623 ff.
CO2‐Minderung in der chemischen Industrie
Authors: Leimkühler H‐J. , Helbig A.
Published: March 2006

Mit dem Start des europäischen CO2‐Zertifikatehandels am 1. Januar 2005 wurden erstmalig Treibhausgasemissionen direkt Kosten zugewiesen. Dieser Mechanismus ist jedoch nur einer von vielfältigen Anreizen zur Minderung von Treibhausgasemissionen in der Industrie. Im Rahmen der Responsible Care‐Initiative hat sich die chemische Industrie bereits seit langem verpflichtet, aktiv ihren Beitrag zum weltweiten Klimaschutz zu leisten. Dieser Beitrag gibt einen Überblick über die aktuellen energiepolitischen und wirtschaftlichen Rahmenbedingungen für die Durchführung von CO2‐Minderungsmaßnahmen in der chemischen Industrie. Der zur Verfügung stehende Maßnahmenkatalog umfasst Verbesserungen der Energieumwandlung, Verfahrensverbesserungen, Standort‐Optimierungen und „End of Pipe”︁‐Technologien. Die einzelnen Maßnahmen werden anhand von Fallbeispielen erläutert.
Automatisierte RNA‐Aufreinigung aus Escherichia coli zur Standardisierung von Microarray‐Experimenten
Authors: Buchholz S. , Stahl F. , Scheper T.
Published: March 2006

Mit Hilfe moderner Biochips, mit denen man die Aktivität tausender Gene gleichzeitig untersuchen kann, sind heute Untersuchungen zur Genexpression und Mutationsdiagnostik in bis vor kurzem nicht vorstellbarem Umfang möglich. Im Gegensatz zu den High‐Throughput‐Chipsystemen ist die zugehörige Nasschemie wie die RNA‐Aufreinigung und cDNA‐Synthese manuell zeitaufwändig durchzuführen, wodurch sich bezüglich Präzision und Reproduzierbarkeit Nachteile ergeben. Daher sind moderne Liquid Handling Tools unentbehrlich.
Bionik im Reagenzglas – Biokatalysator‐Design nach dem Vorbild der Natur durch gerichtete Evolution
Authors: Eggert T.
Published: March 2006

Unter dem Begriff Bionik werden technische Anwendungsprinzipien zusammengefasst, die aus der Natur abgeleitet wurden. Hierzu zählen Entwicklungen wie beispielsweise die Winglets an den Spitzen von Flugzeugflügeln zur Senkung des Treibstoffverbrauchs oder der allseits beliebte Klettverschluss an Taschen oder Kleidungsstücken. Auch in der Biotechnologie kann man sich heute biomimetische Verfahren nicht mehr wegdenken. So werden in der Biokatalysator‐Entwicklung ebenfalls aus der Natur abgeleitete Techniken eingesetzt, die als gerichtete Evolution bezeichnet werden.
Weiße Biotechnologie bei Bayer HealthCare Product Supply: Mehr als 30 Jahre Erfahrung
Authors: Schedel M.
Published: March 2006

Wichtige Projekte der Weißen Biotechnologie, die derzeit bei Bayer HealthCare Product Supply bearbeitet werden, reichen von der Fermentation von Sekundärstoffen über die Herstellung und den Einsatz von Ganzzell‐Biokatalysatoren im Technikums‐ und Produktionsmaßstab bis zur Entwicklung und technischen Nutzung leistungsfähiger rekombinanter Expressionssysteme zur Gewinnung von Proteinwirkstoffen.
Abtrennung von Kohlendioxid aus Rauchgasen mittels Absorption
Authors: Rolker J. , Arlt W.
Published: March 2006

Der steigende Gehalt an Kohlendioxid in der Umgebungsluft und seine klimatischen Auswirkungen haben zu der Erkenntnis geführt, dass die Emissionen in die Luft reduziert werden müssen. Als Prozess zur CO2‐Wäsche aus konventionellen fossil befeuerten Kraftwerken zur Stromerzeugung hat sich die Absorption durchgesetzt, wenngleich derzeit noch keine Anlage existiert, die den realen Kraftwerksfall (Reinigung des gesamten Rauchgasstroms von Kohle‐ oder Gaskraftwerken) abbildet. Weltweit existieren lediglich wenige Pilotanlagen, die die aus der Sauergasreinigung stammende Chemisorption des CO2 und anderen Schwefelverbindungen in wässrige Aminlösungen im kleinen Maßstab untersuchen. In diesem Beitrag werden die besonderen thermodynamischen und prozesstechnischen Anforderungen an eingesetzte und neue Lösungsmittel erläutert. Die Wahl des Lösungsmittels entscheidet ganz maßgeblich über die energetische und ökonomische Effizienz des Absorptions‐ und des Kraftwerksprozesses. Eine gemeinsame Betrachtung/Optimierung beider Prozesse hat unter sinnvollen Zielgrößen und Randbedingungen zu erfolgen. Dazu werden die bereits verwendeten Lösungsmittel nach den oben genannten Kriterien bewertet und einige Vorschläge aus der Literatur hinsichtlich potenzieller neuer Lösungsmittel vorgestellt. Umweltpolitisch interessant ist, dass eine Entfernung von CO2 zwangsläufig zu weiter gesenkten Emissionswerten von Schwefel‐ und Stickstoffoxiden führt.
Die +2‐Grad‐Gesellschaft: Wieviel Klimaschutz ist noch nötig?
Authors: Zellner R.
Published: March 2006

Klimawandel ist nicht länger spekulativ, sondern nachweisbar. Es ist auch belegt, dass zumindest ein großer Teil der beobachteten Klimaänderungen auf menschliche Aktivitäten zurückzuführen ist. Mit der Erkenntnis dieses anthropogen verursachten Klimawandels ist naturgemäß auch die Frage nach der Belastungs‐ bzw. Toleranzgrenze des Globus, d. h. welcher Temperaturanstieg gerade noch akzeptabel sei und welcher bereits einer Klimakatastrophe gleich käme, entstanden. Es gibt keine gute und eindeutige Metrik für eine solche Grenze, denn Klima wird zwar global gemacht, aber dennoch lokal/regional wahrgenommen. Dennoch scheint ein Temperaturanstieg um +2° bis 2100 tolerabel und auch nicht unwahrscheinlich. Aber auch dafür muss noch viel getan werden.
Cyclin E expression is correlated with tumor progression and predicts a poor prognosis in patients with ovarian carcinoma
Authors: Rosen Daniel G. , Yang Gong , Deavers Michael T. , Malpica Anais , Kavanagh John J. , Mills Gordon B. , Liu Jinsong
Published: March 2006

BACKGROUND

Cyclins, cyclin dependent kinases (cdks), and their inhibitors act in combination to regulate progression through the cell cycle and often are dysregulated in carcinoma. The authors hypothesized that cyclin E plays an important role in ovarian carcinogenesis and that its overexpression may be an indicator of a poor prognosis.

METHODS

Immunohistochemical analysis of cyclin E expression was performed by image analysis in normal ovaries, cystadenomas, tumors of low malignant potential, and 405 primary ovarian carcinomas by using tissue microarray technology.

RESULTS

Overexpression of cyclin E was found in 63.2% of the samples and was associated with clear cell, poorly differentiated, and serous carcinoma (P ≤ .001), high‐grade tumors (P ≤ .001), late‐stage disease (P = .002), age older than 60 years at the time of diagnosis (P = .04), and suboptimal cytoreduction (P = .001). A high percentage of cyclin E‐expressing cells was associated with a poor outcome in univariate and in multivariate analyses. In addition, cyclin E levels also reduced survival in the late‐stage disease group and in patients who underwent suboptimal debulking.

CONCLUSIONS

Cyclin E was identified as an independent prognostic factor in patients with ovarian carcinoma. The accumulation of cyclin E protein may be a late event in tumorigenesis and may contribute to disease progression in these patients. Cancer 2006. © 2006 American Cancer Society.
An open‐label, multinational, multicenter study of G17DT vaccination combined with cisplatin and 5‐fluorouracil in patients with untreated, advanced gastric or gastroesophageal cancer : The GC4 study
Authors: Ajani Jaffer A. , Randolph Hecht J. , Ho Linus , Baker Jackie , Oortgiesen Marga , Eduljee Arnavaz , Michaeli Dov
Published: March 2006

BACKGROUND

Gastrin hormone is trophic to in vitro gastric cancer, and the antigastrin antibodies (AGAs) are antiproliferative and antimetastatic. Human gastric cancers overexpress gastrin genes and receptors that react to gastrin's trophic effects. Immunogen G17DT elicits a specific and high‐affinity AGA. The authors evaluated G17DT vaccination given with cisplatin plus 5‐fluorouracil for the treatment gastric adenocarcinoma.

METHODS

In this multicenter, Phase II study, patients received G17DT vaccination intramuscularly on Weeks 1, 5, 9 and 25 and cisplatin plus 5‐fluorouracil every 28 days. Eligible patients had untreated, metastatic, or unresectable gastric or gastroesophageal adenocarcinoma with near‐normal organ function. The primary endpoint of the study was the over response rate (ORR), and secondary endpoints included overall survival (OS), safety, and the impact of successful vaccination on patient outcome.

RESULTS

In total, 103 patients were enrolled in 5 countries. Seven patients who were overdosed inadvertently with 5‐fluorouracil (a major protocol violation) were removed from the analysis. The confirmed ORR was 30% in 79 patients who were evaluated for response. The median time‐to‐progression (TTP) was 5.4 months, and the median survival (MS) was 9.0 months (n = 96 patients). Sixty‐five of 94 patients who were vaccinated (69%) had 2 consecutive AGA titers of ≥1 units (successfully vaccinated patients or immune‐responders). The TTP was longer in immune‐responders than in immune‐nonresponders (P = .0005). Similarly, the MS was longer in immune‐responders than in immune‐nonresponders (10.3 months vs. 3.8 months; P ≤.0001). In a multivariate analysis, successful vaccination was an independent OS prognosticator (P = .0001). G17DT did not have an adverse effect on safety.

CONCLUSIONS

The results demonstrated that successful G17DT vaccination was correlated with longer TTP and MS. AGA response was an independent OS prognosticator. A Phase III evaluation of G17DT in gastric cancer is warranted. Cancer 2006. © 2006 American Cancer Society.
Behavioral and educational limitations after chemotherapy for childhood acute lymphoblastic leukemia or Wilms tumor
Authors: Buizer Annemieke I. , de Sonneville Leo M. J. , van den Heuvel‐Eibrink Marry M. , Veerman Anjo J. P.
Published: March 2006

BACKGROUND

The improved prognosis of childhood cancer makes monitoring of functional outcome important. The purpose of this study was to evaluate behavioral and educational functioning in survivors of childhood acute lymphoblastic leukemia (ALL) or a Wilms tumor. In this study, children with ALL received central nervous system directed chemotherapy without cranial irradiation.

METHODS

In a multicenter study, behavioral functioning and school performance was examined in 199 children age 4 to 18. Sixty‐four children were at least 1 year from finishing treatment with chemotherapy for ALL (n = 28) or a Wilms tumor (n = 36). They were compared with siblings (n = 37) and with a control group of healthy schoolchildren (n = 98).

RESULTS

A moderately increased risk of behavioral and educational problems was found in children with ALL but not in children with Wilms tumor. School performance was poorer in children with ALL attending primary school compared with same‐age peers; however, the rate of utilization of special education services was low. Teacher‐rated behavior and mathematics performance was correlated with attention function in children with ALL. An excess of problem behavior and underperformance at school was found in the ALL high‐risk group compared with the standard‐risk group. No differences were found between siblings and controls.

CONCLUSION

Evidence is provided of subtle but significant behavioral and educational problems in survivors of childhood ALL, but no dysfunctions in survivors of a Wilms tumor. Careful follow‐up of children with ALL treated with chemotherapy only is warranted. Cancer 2006. © 2006 American Cancer Society.
Effects of weight training on quality of life in recent breast cancer survivors
Authors: Ohira Tetsuya , Schmitz Kathryn H. , Ahmed Rehana L. , Yee Douglas
Published: March 2006

BACKGROUND

Aerobic exercise training has been shown to have beneficial effects on quality of life (QOL) in breast cancer survivors. However, the effects of weight training on psychological benefits are unknown. We sought to examine the effects of weight training on changes in QOL and depressive symptoms in recent breast cancer survivors.

METHODS

A convenience sample of 86 survivors (4‐36 months posttreatment) was randomized into treatment and control groups. The primary outcomes were changes in QOL (CARES short form) and depressive symptoms (CES‐D) between baseline and month 6 in this randomized controlled trial.

RESULTS

Over 6 months the physical global QOL score improved in the treatment group compared with the control group (Standardized Difference = 0.62, P = .006). The psychosocial global score also improved significantly in the treatment group compared with the control group (Standardized Difference = 0.52, P = .02). There were no changes in CES‐D scores. Increases in upper body strength were correlated with improvements in physical global score (r = 0.32; P <.01) and psychosocial global score (r = 0.30; P <.01). Increases in lean mass were also correlated with improvements in physical global score (r = 0.23; P <.05) and psychosocial global score (r = 0.24; P <.05).

CONCLUSION

Twice‐weekly weight training for recent breast cancer survivors may result in improved QOL, in part via changes in body composition and strength. Cancer 2006. © 2006 American Cancer Society.
Left versus right nipple preference in free‐ranging infant rhesus macaques (Macaca mulatta)
Authors: Jaffe Benjamin D. , Evans Theodore A. , Howell Sue , Westergaard Gregory C. , Snoy Philip J. , Higley J. Dee
Published: March 2006

The examination of nonhuman primate (NHP) lateralized behaviors may provide insight into the evolution of hemispheric specialization. This study examined nipple preference in 64 infant macaques in order to consider the ontogeny of lateralized behavior. We used a focal animal sampling method to record nipple contact during 15, 30‐min observation sessions collected across each infant's first year of life. Using a lateralized behavior index (LBI) we calculated individual and population preferences (LBI = (R−L)/(R + L); “R” = mean right nipple contact, “L” = mean left nipple contact). Strength of preference was calculated as the absolute value of this score. Infants exhibited no population preference for a particular nipple, but showed a significant strength of preference that developed after 48 hr. Interestingly, successive siblings preferred the nipple not used by the previous infant. These findings suggest that nipple preference is guided by external stimuli, and that nipple preference during infancy may not be a behavioral representation of hemispheric specialization. © 2006 Wiley Periodicals, Inc. Dev Psyshobiol 48: 266–272, 2006.
The ontogeny of autonomic measures in 6‐ and 12‐month‐old infants
Authors: Alkon Abbey , Lippert Suzanne , Vujan Nicole , Rodriquez Marya Eugenya , Boyce W. Thomas , Eskenazi Brenda
Published: March 2006

The purpose of this study was to develop a standardized protocol to measure preejection period (PEP), a measure of sympathetic nervous system, and respiratory sinus arrhythmia (RSA), a measure of parasympathetic nervous system, during resting and challenging states for 6‐ and 12‐month‐old infants and to determine developmental changes and individual stability of these measures. A 7‐min reactivity protocol was administered to Latino infants at 6 months (n = 194) and 12 months (n = 181). Results showed: (1) it is feasible to measure PEP and RSA in infants, (2) the protocol elicited significant autonomic changes, (3) individual resting autonomic measures were moderately stable from 6 to 12 months, but reactivity measures were not stable, and (4) heart rate and RSA resting and challenge group means changed significantly from 6 to 12 months. Findings suggest that although infants' autonomic responses show developmental changes, individuals' rank order is stable from 6 to 12 months of age. © 2006 Wiley Periodicals, Inc. Dev Psyshobiol 48: 197–208, 2006.
Neonatal behavior and infant cognitive development in rhesus macaques produced by assisted reproductive technologies
Authors: Sackett Gene , Ruppenthal Gerald , Hewitson Laura , Simerly Calvin , Schatten Gerald
Published: March 2006

Assisted reproductive technologies (ART) used in fertility clinics include in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), followed by embryo transfer into the biological or a surrogate mother. Over 1,000,000 liveborn offspring—an estimated 1 in 150 United States newborns—have been produced worldwide by ART since 1978. IVF appears to produce healthy children in singleton pregnancies, though concerns remain regarding preterm deliveries, multiple pregnancies, as well as the longer‐term consequences of all ART procedures. Clinical studies remain difficult to interpret and subject to confounding variables, as developmental problems may be due to a parent's reproductive conditions rather than, or in addition to, an ART procedure. Also, because of expense and time commitments, the United States ART clinical population is not fully representative of society diversities. This socio‐economic skewing might compensate for negative effects, masking small, or modest developmental deficits. Embryo splitting (ES), an ART procedure used only with animals, can produce genetically identical offspring. ES involves dividing four‐ to eight‐cell embryos into separate blastomeres and implanting them into empty zona pellucida, followed by embryo transfer. Although these ART techniques have produced nonhuman primate offspring, there has been no research on behavioral safety. Here, we report the first study of behavioral development by rhesus macaques infants produced through ES, ICSI, and IVF. We assessed neonatal reflexes, self‐feeding ability, recognition memory, object concept attainment, simple discrimination learning and reversal, and learning set (LS) acquisition. Although the sample sizes are small, we found no overall ART group delayed development. Surprisingly, the ES and ICSI monkeys appeared to be accelerated in attaining age milestones involving sensory‐motor behaviors and a difficult Well Hiding object concept task. We conclude that macaque monkeys may provide an excellent model for the study of early human development by offspring of parents with conditions requiring ART pregnancies, as well as a model for the behavioral study of genetic–environment interactions using identical twins produced by ES. © 2006 Wiley Periodicals, Inc. Dev Psyshobiol 48: 243–265, 2006.
Effects of novelty on behavior in the adolescent and adult rat
Authors: Stansfield Kirstie H. , Kirstein Cheryl L.
Published: March 2006

Adolescence is a time of high‐risk behavior and increased exploration. This developmental period is marked by a greater probability of initiating drug use and is associated with an increased risk to develop addiction and dependency in adulthood. Human adolescents are predisposed towards an increased likelihood of risk taking behaviors (Zuckerman, 1986), including drug use or initiation. The purpose of the study was to examine differences in developmental risk taking behaviors. Adolescent and adult animals were exposed to a novel stimulus in a familiar environment to assess impulsive behaviors, novelty preference, and exploratory behaviors. Adolescent animals had greater novelty‐induced locomotor activity, greater novelty preference, and showed higher approach and exploratory behaviors compared to adult animals. These data support the notion that adolescents may be predisposed toward sensation seeking and consequently, are more likely to engage in risk‐taking behaviors, such as drug use initiation. © 2006 Wiley Periodicals, Inc. Dev Psyshobiol 48: 273, 2006.
Die Koordinierungsstelle für die harmonisierte europäische Normung im Bereich der Bauproduktenrichtlinie im DIBt. Aktuelle Entwicklungen im Zusammenhang mit harmonisierten europäischen Normen
Authors: Springborn Matthias
Published: March 2006

Vor inzwischen mehr als drei Jahren wurde beim DIBt die Koordinierungsstelle für die Mitarbeit der Bauaufsicht in der harmonisierten europäischen Normung nach der Bauproduktenrichtlinie (BPR) eingerichtet – Zeit genug, um etliche Erfahrungen mit solchen harmonisierten Normen zu sammeln. Zweimal wurde über solche Erfahrungen bereits berichtet (siehe “DIBt Mitteilungen”, Hefte Nr. 4/2004 und Nr. 1/2005). Der erste Bericht stellte vor allem die Aufgaben der Koordinierungsstelle vor und ging insofern auf die bisher gemachten Erfahrungen mit harmonisierten Normen nach BPR und mit deren Mängeln ein, als ein Merkblatt für die Mitarbeit von Vertretern der Bauaufsicht an der harmonisierten Normung vorgestellt wurde, dass diese Erfahrungen widerspiegelt. Der zweite Bericht hat dann diese Erfahrungen konkreter und an Beispielen ausgeführt.

Dieser dritte Beitrag kann zu den oben genannten Punkten nichts Neues bieten – insbesondere leider keine Erfahrungen mit grundlegenden Verbesserungen im Bereich der harmonisierten Normung. Im Gegenteil, das letzte Jahr war gekennzeichnet durch zwei von Deutschland über die deutsche Delegation im Ständigen Ausschuss für das Bauwesen (StAB) eingeleitete Verfahren nach Artikel 5 Absatz 1 der Bauproduktenrichtlinie. Dieses Verfahren hat die offizielle Zurückziehung der Referenz für harmonisierte Normen zum Ziel mit der Folge, dass diese Normen nicht mehr den Status von harmonisierten Normen haben. Ein weiteres Verfahren wurde von der französischen Delegation eingeleitet.

Ein zweiter Schwerpunkt dieses Beitrags ist die neue Form der Bekanntmachungen von harmonisierten Normen in der Reihe C des Amtsblatts der EU. Erstmals am 8. Juni 2005 haben die Dienste der Kommission in der Nr. C 139 des Amtsblatts eine konsolidierte Liste aller harmonisierten Normen bekannt gemacht. Die europäische Normungsorganisation CEN (Comit� Europ�en de Normalisation) hatte im Frühjahr 2005 den Kommissionsdiensten zugesagt, in Zukunft alle 3 Monate eine solche Liste zu liefern, so dass eigentlich davon auszugehen war, dass im gleichen Abstand eine entsprechende Bekanntmachung im Amtsblatt der EU erfolgt. Dies ist jedoch bisher nicht der Fall; die zweite und bisher letzte Bekanntmachung dieser Art erfolgte im Amtsblatt der EU Nr. C 319 vom 14. Dezember 2005. Die Kommission gibt am Ende dieser Bekanntmachungen den Hinweis, dass sie jeweils alle vorherigen Bekanntmachungen harmonisierter Normen nach BPR ersetzen.
Bauaufsichtliche Verwendbarkeitsnachweise für Bauprodukte und Bauarten für Anlagen zum Lagern und Abfüllen von Jauche, Gülle und Silagesickersäften – unter besonderer Berücksichtigung der Erteilung allgemeiner bauaufsichtlicher Zulassungen für mit Dichtungsbahnen ausgekleideten Gülleerdbecken
Authors: Strathmann Brigitte
Published: March 2006

Im folgenden Artikel wird dargestellt, welche bauaufsichtlichen Verwendbarkeitsnachweise für Bauprodukte und Bauarten für Anlagen zum Lagern und Abfüllen von Jauche, Gülle und Silagesickersäften (JGS‐Anlagen) erforderlich sind. Hierbei wird auch der Zusammenhang zwischen den bauaufsichtlichen Verwendbarkeitsnachweisen für diese Bauprodukte und Bauarten und den Anforderungen gemäß § 19 g Wasserhaushaltsgesetz (WHG) beschrieben.

Des Weiteren wird auf die Anforderungen, die im Rahmen der Erteilung allgemeiner bauaufsichtlicher Zulassungen für Bauprodukte und Bauarten für JGS‐Anlagen – insbesondere von mit Dichtungsbahnen ausgekleideten Gülleerdbecken – zu erbringen sind, eingegangen. Das DIBt erteilt schon seit längerem allgemeine bauaufsichtliche Zulassungen für Bauprodukte und Bauarten für Anlagen zum Lagern, Abfüllen und Umschlagen wassergefährdender Stoffe. Jauche, Gülle und Silagesickersäfte nehmen aber im Rahmen der wassergefährdenden Stoffe eine Sonderstellung ein, die in diesem Artikel erläutert werden soll. Ferner soll der Beitrag eine Hilfestellung zur Suche von technischen Regeln, die für Bauprodukte und Bauarten für JGS‐Anlagen gelten, geben.
Towards an Understanding of the Polar Diels–Alder Reactions of Nitrosoalkenes with Enamines: A Theoretical Study
Authors: Domingo Luis R. , Picher M. Teresa , Arroyo Pau
Published: March 2006

The polar Diels–Alder reactions of nitrosoalkenes with enamines have been studied using DFT methods at the B3LYP/6‐31G* level of theory. These Diels–Alder reactions are characterized by a nucleophilic attack of the enamine at the conjugated position of the nitrosoalkene with concomitant ring‐closure. The reactions present a total regioselectivity and a largeendoselectivity. The analysis, based on the global electrophilicity of the reagents in the ground state, the natural bond orbital (NBO), and the topological analysis of the electron localization function (ELF) in theendotransition state (TS) and “halfway” along the IRC between the TS and cycloadduct, correctly explain the polar nature of these cycloaddition reactions. The large electrophilic character of nitrosoethylenes together with the large nucleophilic character of enamines are responsible for the large acceleration found in these polar Diels–Alder reactions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis and Photophysical Properties of the 4‐(Biphenyl‐4‐yl)‐2,6‐bis(4‐iodophenyl)pyrylium Ion
Authors: Álvaro Mercedes , Aprile Carmela , Carbonell Esther , Ferrer Belén , García Hermenegildo
Published: March 2006

A triarylpyrylium ion containing iodo and biphenyl substituents has been synthesized and its photophysical properties measured. Compared to its parent triphenylpyrylium ion,the photophysical data recorded for 4‐(biphenyl‐4‐yl)‐2,6‐bis(4‐iodophenyl)pyrylium are significantly influenced by substitution. Remarkable decreases in fluorescence and phosphorescence quantum yields, a shorter singlet lifetime, and lower energies of the singlet and triplet excited states are observed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Cerium‐Catalyzed α‐Hydroxylation Reactions of α‐Cyclopropyl β‐Dicarbonyl Compounds with Molecular Oxygen
Authors: Christoffers Jens , Kauf Thomas , Werner Thomas , Rössle Michael
Published: March 2006

Three α‐cyclopropyl β‐dicarbonyl compounds have been used as probes for α‐radicals as electrophilic reaction intermediates in a cerium‐catalyzed α‐hydroxylation reaction with molecular oxygen. Since the cyclopropyl group did not ring‐open to products with a butenyl moiety, but was retained in the products, a localized unpaired electron at the α position can be excluded during the course of the reaction. The α‐cyclopropyl‐substituted substrates were prepared by aldol or Claisen reactions. Other substrates with α‐methyl, α‐isopropyl, and α‐tert‐butyl substituents were prepared and converted under the α‐hydroxylation conditions in order to estimate steric influences on the yield of the reaction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Stability, morphology and surface grain size patterns of channel bifurcation in gravel–cobble bedded anabranching rivers
Authors: Burge Leif M.
Published: March 2006

This study presents the first detailed field‐based analysis of the morphology of bifurcations within anabranching cobble–gravel rivers. Bifurcations divide the flow of water and sediment into downstream anabranches, thereby influencing the characteristics of the anabranches and the longevity of river islands. The history, morphology, bed grain size, and flow vectors at five bifurcations on the Renous River, New Brunswick, Canada, were studied in detail. The angles of bifurcations within five anabranching rivers in the Miramichi basin were investigated. The average bifurcation angle was 47°, within the range of values cited for braided river bifurcations. Bifurcation angle decreased when anabranches were of similar length. Shields stresses in channels upstream of bifurcations were lower than reported values for braided rivers. Stable bifurcations displayed lower Shields stresses than unstable bifurcations, contrary to experimental results from braided river bifurcations. Bifurcations in anabranching rivers are stabilized by vegetation that slows channel migration and helps to maintain a uniform upstream flow field. The morphology of stable bifurcations enhances their stability. A large bar, shaped like a shallow ramp that increases in elevation to floodplain level, forms at stable bifurcations. Floodplains at stable bifurcations accrete upstream at rates between 0·9 and 2·5 m a−1. Bars may also form within the entrance of an anabranch downstream of the bifurcation node. These bars are associated with bifurcation instability, forming after a period of stability or an avulsion. Channel abandonment occurs when a bar completely blocks the entrance to one anabranch. The stability of channels upstream of bifurcations and the location of bars at bifurcations influence bifurcation stability and the maintenance of river anabranching in the long term. Copyright © 2006 John Wiley & Sons, Ltd.
Mitochondrial DNA mutations and mitochondrial DNA depletion in breast cancer
Authors: Tseng Ling‐Ming , Yin Pen‐Hui , Chi Chin‐Wen , Hsu Chih‐Yi , Wu Chew‐Wun , Lee Liang‐Ming , Wei Yau‐Huei , Lee Hsin‐Chen
Published: March 2006

Somatic mutations in mitochondrial DNA (mtDNA) have been demonstrated in various tumors, including breast cancer. However, it still remains unclear whether the alterations in mtDNA are related to the clinicopathological features and/or the prognosis in the breast cancer. We analyzed somatic mutations in the D‐loop region, the common 4,977‐bp deletion, and the copy number of mtDNA in breast cancer and paired nontumorous breast tissues from 60 Taiwanese patients. We found that 18 of the 60 (30%) breast cancers displayed somatic mutations in mtDNA D‐loop region. The incidence of the 4,977‐bp deletion in nontumorous breast tissues (47%) was much higher than that in breast cancers (5%). The copy number of mtDNA was significantly decreased in 38 of the 60 (63%) breast cancers as compared to their corresponding nontumorous breast tissues (P = 0.0008). The occurrence of D‐loop mutations was associated with an older onset age (≥50 years old, P = 0.042), and tumors that lacked expressions of estrogen receptor and progesterone receptor (P = 0.024). Patients with mtDNA D‐loop mutation and breast cancer had significantly poorer disease‐free survival than those without mutation, when assessed by Kaplan–Meier curves and log‐rank test (P = 0.005). Multivariate Cox regression analysis indicated that a D‐loop mutation is a significant marker that is independent of other clinical variables and that it can be used to assess the prognosis of patients. Our findings suggest that somatic mutations in mtDNA D‐loop can be used as a new molecular prognostic indicator in breast cancer. © 2006 Wiley‐Liss, Inc.
Functional imaging analysis contest (FIAC) analysis according to AFNI and SUMA
Authors: Saad Ziad S. , Chen Gang , Reynolds Richard C. , Christidis Patricia P. , Hammett Kenneth R. , Bellgowan Patrick S.F. , Cox Robert W.
Published: March 2006

The Functional Imaging Analysis Contest (FIAC) datasets were analyzed with the AFNI software package. Two types of linear regression analyses were carried out: “fixed shape” hemodynamic response, where a preselected incomplete gamma function is used to model each brief activation episode, and “variable shape” analysis, where the temporal shape of the response model in each stimulus block class is allowed to vary separately in each voxel. These time series regressions were carried out both in the volume and on the original data projected to individual standardized cortical surface models. Intersubject analyses were carried out voxel‐wise on the regression amplitudes obtained from these time series results, using a multi‐way within‐subject analysis of variance (ANOVA). Group analysis of the block design demonstrated a significant repetition suppression of the BOLD signal within blocks in the superior and middle temporal gyrus. This effect may represent differences in the response to the first stimulus following a period of silence compared to the remaining sentences in the block. Analyzing the event‐related data, Brodmann area 31 showed significant sentence effect and consecutive‐sentence repetition effect. However, no significant speaker effect was found; these results may be consistent with the instructions to the subjects that they would be tested on the sentence content. Sentence by speaker interaction effects were found in bilateral middle temporal gyrus, left inferior frontal, and left inferior temporal gyrus. Hum Brain Mapp, 2006. © 2006 Wiley‐Liss, Inc.
Modelling the effects of saline water use in agriculture
Authors: Kaledhonkar M. J. , Keshari Ashok K.
Published: March 2006

Use of saline groundwaters is inevitable in rice–wheat, cotton–wheat, and millet–wheat crop rotations in the northern region of India due to limited canal water supplies. The UNSATCHEM model is calibrated and validated with field data on saline water use for the wheat and cotton crop. The calibrated and validated model has been employed to study different aspects of the salinisation process. The effect of irrigation water quality on the salinisation process is understood with the help of simulations in which irrigation waters of different SAR, SO and Cl− concentrations are used. A linear relation is observed between the weighted average of irrigation water salinity and the root zone. The salinisation process under different conjunctive use practices is understood through simulations. The practices are compared on the basis of temporal changes in root zone salinity with reference to the sensitivity of the wheat crop to salinity for deciding the preference of one conjunctive use practice over another. The preference order, thus prepared, is verified with the published yield data of wheat from conjunctive use field studies. The effect of soil texture on salinisation is studied through simulations. The saturated water content influences the salinisation process more than the hydraulic conductivity. The long‐term simulations as per water quality guidelines for a six‐year period under wheat–cotton rotation are carried out to assess the sustainability of saline water use for crop production. Copyright © 2006 John Wiley & Sons, Ltd.
Validation of the FAO methodology for computing ETo with limited data. Application to south Bulgaria
Authors: Popova Zornitsa , Kercheva Milena , Pereira Luis S.
Published: March 2006

The calculation of reference evapotranspiration ETo with the FAO Penman‐Monteith method (FAO‐PM) requires maximum and minimum air temperature (Tmax and Tmin), actual vapour pressure (ea), net radiation (Rn), namely computed from sunshine duration or short wave solar radiation (Rs), and wind speed at 2 m (u2). However, some of these weather variables, especially solar radiation, are often missing in irrigation practice. To overcome these problems, procedures to estimate ETo with missing climate data are proposed as part of the FAO‐PM methodology and it is important to assess the accuracy of these procedures for different climate conditions. This is the objective of this study relative to the Trace plain, south Bulgaria, where data relative to five meteorological stations in the Trace plain are analysed. All stations are located within a homogeneous physiographic region where the air masses governing the weather are the same. The procedures to estimate the missing radiation data refer to the use of the maximum and the minimum daily temperature differences and data from a neighbouring station. Procedures to estimate missing humidity data relate to the use of minimum temperature data and those for the wind speed data refer to regional average data. The accuracy of all different procedures analysed was assessed by regressing ETo values calculated with the FAO‐PM equation computed with limited data versus ETo values computed with complete data sets. Statistical parameters of the regression through the origin and the computed standard errors of estimates (SEE) were used. It could be concluded that the procedures proposed by FAO are accurate providing small SEE, including when only maximum and minimum temperature data are used, which yields lower SEE than when using the Hargreaves equation, which tends to overestimate ETo for the observed conditions. Copyright © 2006 John Wiley & Sons, Ltd.
Water management tasks in the summer polders of the Nemunas lowland
Authors: Lukianas Antanas , Vaikasas Saulius , Malisauskas Arvydas Povilas
Published: March 2006

Surplus water during floods as well as the low level of the soil surface determine the complicated ecological, economic and demographic conditions in the Nemunas delta. Subsequently, it leads to different types and intensity of use of farmland as well as different methods of water regime regulation: summer or winter type polders. The building of 17 summer polders in the 32 500 ha floodplain area was a compromise, seeking to improve farming conditions and maintain the stability of the flood regime and ecology in the delta. Field measurements and mathematical modelling were carried out. As study results have shown, grass yield losses due to flooding depend on the distribution of water levels and flood duration in the summer polders. Relative damage to agriculture is insignificant and makes up only 10–15% of the total amount of flood damage in the Nemunas lowland.

The field measurements and hydraulic and mathematical modelling of flow and sediment regime as well as study of flooding and changed farming conditions also show that it is possible to reduce the height of floods and economic and ecological damage. Rearrangement of the system of protective dikes, regulation of the main river canal and water/sedimentation regime with the help of pumping stations, decrease of pollutant migration into the Curonian Lagoon and Baltic Sea, and recreation of natural meadows are important in that case. Copyright © 2006 John Wiley & Sons, Ltd.
Photopolymerization of biomaterials: issues and potentialities in drug delivery, tissue engineering, and cell encapsulation applications
Authors: Baroli Biancamaria
Published: March 2006

Photopolymerization is a widely explored technology that has recently been recognized to have also great potentialities in the biomedical field. This paper aims to provide a general overview of this technology by briefly describing materials and methods used to produce linear or crosslinked polymer networks for drug delivery, tissue engineering and cell encapsulation. In addition, potentialities and areas of investigation that are not fully explored but that could provide solutions for better control over the technology when applied to the biomedical field will be indicated as well. Copyright © 2006 Society of Chemical Industry
The effect of selected parameters of formation on properties of alginate/Ca2+/oligochitosan capsules
Authors: Bartkowiak Artur , Lisiecki Sławomir , Orive Gorka , Pedraz Jose Luis
Published: March 2006

Optimization of the technological parameters affecting the mechanical properties and permeability of capsules is essential to produce capsules with improved properties for cell immobilization. In the present paper, the effect of different parameters on the technological properties of alginate/Ca2+/oligochitosan capsules has been investigated. The correct adjustment of the alginate concentration in the polymer matrix and the oligochitosan molar mass, concentration and coating time, have been found to be key parameters in obtaining porous and mechanically stable alginate/Ca2+/oligochitosan capsules. Results showed that an increase in the coating time and concentration of the alginate generated more stable capsules with a reduced membrane cut‐off. Furthermore, we have established some correlations between capsule properties and the effectiveness of chitosan binding within the capsule's membrane. Data addressed herein could be a valid tool to fabricate optimized alginate/Ca2+/oligochitosan capsules with a potential for use in cell immobilization technology. Copyright © 2006 Society of Chemical Industry
Thermodynamics of the encapsulation by cyclodextrins
Authors: Charumanee Suporn , Titwan Aurawan , Sirithunyalug Jakkapan , Weiss‐Greiler Petra , Wolschann Peter , Viernstein Helmut , Okonogi Siriporn
Published: March 2006

Molecular encapsulation on a molecular basis can be performed by cyclodextrins. The inclusion of organic molecules into the interior changes the properties of these molecules, which may be used for a broad variety of applications. The affinity of guest molecules for the cavities of various cyclodextrins depends on the stereochemistry and on the interaction forces of the molecules involved. Calculations of the thermodynamic parameters show that the reaction entropy is highly important for the inclusion reaction. Completely different reaction mechanisms are observed for various types of cyclodextrins as some of these reactions show enthalpy–entropy compensation. Others are supported by the reaction entropy or are even entropically controlled. Protonation and deprotonation reactions contribute significantly to the inclusion reaction, as first of all the solubility of the compounds in water is strongly influenced by the acidity of the solution, and, moreover, all tautomeric forms of the compounds show different affinities to various cyclodextrins. Copyright © 2006 Society of Chemical Industry
EPRI to estimate the in vivo intracerebral reducing ability in adolescent rats subjected to neonatal isolation
Authors: Yokoyama Hidekatsu , Morinobu Shigeru , Ueda Yuto
Published: March 2006

Purpose

To estimate the in vivo intracerebral reducing ability after acute stress in adolescent rats subjected to early neonatal isolation (NI), by performing temporal electron paramagnetic resonance imaging (EPRI) of the brain.

Materials and Methods

An EPRI system operating at an EPR frequency of 700 MHz was used. The intracerebral reducing ability was estimated based on the halflife of the EPR signal of the blood–brain barrier (BBB)‐permeable nitroxide radical. The NI treatment was performed for a period of one hour per day over postnatal days 2–9. Six‐week‐old rats were exposed to acute stress (immobilization for 90 minutes) prior to the EPRI study.

Results

Depletion of the intracerebral reducing ability caused by the acute stress was observed; however, this depletion phenomenon did not occur in animals that were not subjected to NI.

Conclusion

The results obtained in this study prove that NI induces cerebral vulnerability to acute stress in adolescence. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Multislice multiecho T2* cardiovascular magnetic resonance for detection of the heterogeneous distribution of myocardial iron overload
Authors: Pepe Alessia , Positano Vincenzo , Santarelli Maria Filomena , Sorrentino Fortunato , Cracolici Eliana , De Marchi Daniele , Maggio Aurelio , Midiri Massimo , Landini Luigi , Lombardi Massimo
Published: March 2006

Purpose

To assess the tissue iron concentration of the left ventricle (LV) using a multislice, multiecho T2* MR technique and a segmental analysis.

Materials and Methods

T2* multiecho MRI was performed in 53 thalassemia major patients. Three short‐axis views of the LV were obtained and analyzed with custom‐written software. The myocardium was automatically segmented into 12 segments. The T2* value on each segment as well as the global T2* value were calculated. Cine dynamic images were also obtained to evaluate biventricular function parameters by quantitative analysis.

Results

For the T2* global value, the coefficient of variation (CoV) for intra‐/interobserver and interstudy reproducibility was 3.9% (r = 0.98), 5.5% (r = 0.98), and 4.7% (r = 0.99) respectively. Three groups were identified based on analysis of myocardial T2*: homogeneous (21%), heterogeneous (38%), and no myocardial iron overload (41%). The mean serum ferritin, liver iron concentration, and urinary iron excretion were significantly different among the groups. We did not find significant differences among groups in biventricular function. There was a correlation between the global T2* value and the T2* value in the mid‐ventricular septum (r = 0.95, P < 0.0001).

Conclusion

Multislice multiecho T2* MRI provides a noninvasive, fast, reproducible means of assessing myocardial iron distribution. The single measurement of mid‐septal T2* correlated well with the global T2* value. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Breath‐hold 3D steady‐state free precession coronary MRA compared with conventional X‐ray coronary angiography
Authors: Cheng Liuquan , Gao Yuangui , Guaricci Andrea I. , Mulukutla Suresh , Sun Wei , Sheng Fugeng , Foo Thomas K. , Prince Martin R. , Wang Yi
Published: March 2006

Purpose

To evaluate the use of breath‐hold three‐dimensional (3D) steady‐state free precession (SSFP) coronary magnetic resonance angiography (MRA) in patients with coronary artery disease (CAD) in comparison with conventional coronary x‐ray angiography (XRA).

Materials and Methods

Twenty‐eight patients with suspected CAD were examined with the use of a breath‐hold 3D‐SSFP‐MRA sequence and conventional XRA. To assess the accuracy of MRA, two clinicians who were blinded to patient information independently reviewed the MRA and XRA data, which were presented in a randomized order. To identify discrepancies between MRA and XRA, and assess features of coronary lesions on MRA, two additional clinicians examined MRA and XRA data that were presented side by side, divided into proximal, mid, and distal segments, and compared them segment by segment.

Results

The sensitivity and specificity for diagnosing significant coronary stenoses (>50% diameter narrowing) were 64% and 94%, respectively. At sites of coronary lesions identified on XRA, bright signals and enlarged vessel profiles, in addition to the characteristic narrow lumen, were frequently observed on MRA.

Conclusion

Breath‐hold SSFP coronary MRA has good specificity but inconclusive sensitivity in diagnosing significant coronary stenoses, and provides important image features for depicting coronary lesions. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
The multiple pathways of high performing groups: the interaction of social networks and group processes
Authors: Shah Priti Pradhan , Dirks Kurt T. , Chervany Norman
Published: March 2006

This study examines how both strong and weak relationship groups (groups with numerous, intense internal friendship ties and few, less intense internal friendship ties respectively) achieve high performance when utilizing strategies that capitalize on the strengths and minimizing the weaknesses associated with their internal social structure. We examine the interactions of groups' internal friendship networks with their external network structures (external ties) and internal intragroup conflict (constructive controversy). The results of a study using survey, archival and interview data on 35 groups of MBA students indicated that internal friendship networks interacted with constructive controversy and external networks to determine when groups would achieve superior performance. High performing strong relationship groups engaged in greater constructive controversy than low performing strong relationship groups, while constructive controversy appeared to have minimal effect on the performance of weak relationship groups. High performing weak relationship groups had fewer external bridging ties to other groups when compared to low performing weak relationship groups, while external bridging ties appeared to have minimal effect on the performance of strong relationship groups. Copyright © 2006 John Wiley & Sons, Ltd.