bluuebunny/crossref_metadata_2025 huggingface dataset:
Diabetic Retinal Neurodegeneration Is Associated With Mitochondrial Oxidative Stress and Is Improved by an Angiotensin Receptor Blocker in a Model Combining Hypertension and Diabetes
Authors: Silva Kamila C. , Rosales Mariana A.B. , Biswas Subrata K. , Lopes de Faria Jose B. , Lopes de Faria Jacqueline M.
Published: March 2009

OBJECTIVE

Diabetic retinopathy displays the features of a neurodegenerative disease. Oxidative stress is involved in the pathogenesis of diabetic retinopathy. This investigation sought to determine whether hypertension exacerbates the oxidative stress, neurodegeneration, and mitochondrial dysfunction that exists in diabetic retinopathy and whether these changes could be minimized by the angiotensin II type 1 (AT1) receptor blocker (ARB) losartan.

RESEARCH DESIGN AND METHODS

Diabetes was induced in spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto (WKY) rats. The diabetic SHRs were assigned to receive or not receive losartan.

RESULTS

The level of apoptosis in the retina was higher in diabetic WKY rats than in the control group, and higher levels were found in diabetic SHRs. The apoptotic cells expressed neural and glial markers. The retinal glial reaction was more evident in diabetic WKY rats and was markedly accentuated in diabetic SHRs. Superoxide production in retinal tissue increased in diabetic WKY rats, and a greater increase occurred in diabetic SHRs. Glutathione levels decreased only in diabetic SHRs. As a consequence, the levels of nitrotyrosine and 8-hydroxy 2′-deoxyguanosine, markers of oxidative stress, were elevated in diabetic groups, mainly in diabetic SHRs. Mitochondrial integrity was dramatically affected in the diabetic groups. The ARB treatment reestablished all of the above-mentioned parameters.

CONCLUSIONS

These findings suggest that concomitance of hypertension and diabetes exacerbates oxidative stress, neurodegeneration, and mitochondrial dysfunction in the retinal cells. These data provide the first evidence of AT1blockage as a neuroprotective treatment of diabetic retinopathy by reestablishing oxidative redox and the mitochondrial function.
Association of Endogenous Sex Hormones With Diabetes andImpaired Fasting Glucose in Men
Authors: Colangelo Laura A. , Ouyang Pamela , Liu Kiang , Kopp Peter , Golden Sherita Hill , Dobs Adrian S. , Szklo Moyses , Vaidya Dhananjay , Cushman Mary , Gapstur Susan M.
Published: March 2009

OBJECTIVE

To assess associations of sex hormones with impaired fasting glucose (IFG) and type 2 diabetes in men.

RESEARCH DESIGN AND METHODS

A total of 3,156 African American, Non-Hispanic white, Hispanic, and Chinese-American men aged 45–84 years who participated in the baseline visit of the Multi-Ethnic Study of Atherosclerosis (MESA) were included. Oddsratios and95% CIs for type 2 diabetes and IFG compared with normal fasting glucose for quartiles of hormones were estimated.

RESULTS

After adjusting for age, ethnicity, BMI, and waist circumference, IFG and diabetes were associated inversely with total testosterone and sex hormone–binding globulin (SHBG) and positively with estradiol (E2). Dehydroepiandrosterone was positively associated with IFG but not with diabetes. Associations did not differ across ethnic groups.

CONCLUSIONS

Regardless of obesity, total testosterone and SHBG were associated inversely and E2 was associated positively with IFG and diabetes in men. Further research is warranted to better understand the underlying biological mechanisms.
Marji: Popular Commix Heroine Breathing Life into the Writing of History
Authors: Costantino Manuela
Published: March 2009

Marjane Satrapi's graphic memoir Persepolis has become an extremely popular text in the last few years. Part of the power of Satrapi's memoir is that it recreates her childhood experience in Iran at the time of the Cultural Revolution, in the graphic genre. The combination of a visual representation and a child's point of view makes the story easily accessible and therefore attracts a wide range of readers. This easy access to the story, however, can lead to the assumption that the child's perspective is uncomplicated by the nuances of an adult point of view and the seemingly simple text is transparent, articulating only one meaning. This paper complicates such a simplistic reception of the text and explores the various cultural and political forces at work in the articulation of the contexts for the production and reception of Persepolis in both France and North America.
Karyotypic Study of seven Types of Impatiens balsamina L.
Authors: Momtaz USN , Kabir G , Ud-deen MM , Yasmin N
Published: March 2009

Nuclear phenotype and chromosome characteristics of eight types of Impatiens balsamina L. were studied. The diploid chromosome number was found to be 2n=14 in all types of Impatiens balsamina. Interphase chromosome volume was found to range from 0.1665Î¼3 (violet type) to 0.3904 Î¼3 (red type). The maximum total chromatin length (24.73Î¼m) was observed in pink type and minimum (11.70Î¼m) in violet type. Maximum total frequency percent (50.00%) was found in both foreign types (red and violet) and minimum (48.03%) in violet type. The karyotype analysis revealed that there was no secondary constriction and sub-terminal chromosome in any of the seven types belonging to Impatiens balsamina. So, on the basis of karyotypic analysis the present findings indicated that all the types of Impatiens balsamina were of primitive nature. Key words: Karyotype, Nuclear phenotype, Impatiens balsamina L. Â  doi: 10.3329/jbs.v15i0.2155 Â Â  J. bio-sci. 15: 147-152, 2007
Status of Aquarium Fisheries of Rajshahi City
Authors: Mohsin ABM , Haque Md Emdadul , Islam Md Nazrul
Published: March 2009

An aquarium is an enclosed body of water containing a mixture of selected and unselected captive living aquatic organism. It is essentially unstable and to obtain stability must be carefully designed and managed (Suxena 2003). Recently aquarium technology means that the technical problems of keening aquatic animals have in principle been solved. It includes about water preparation and the constant monitoring of water quality i.e. pH, hardness, dissolve oxygen, temperature etc. and for this heater, pumps and filter is used. For first time colorful fishes are imported in our country in 1992 and the business was confined in some limited shops of Katabaon area of Dhaka city. But now this business is very common in all over the country (Akhter 1995). It is not only enhancing the beauty of a house but also it is a source of recreation. Japanese can realize the presage of earthquake or can predict about natural disaster by watching the sudden movement of the aquarium fishes (Shafi 1998). Similarly to get rid of mental stress, watching fish is reported well and this also helps to decrease the high blood pressure (Hervert 1999). In Rajshahi city aquarium business started at the last decade and it is spreading rapidly. So development of aquarium fisheries is highly significant here. Â  doi: 10.3329/jbs.v15i0.2159 J. bio-sci. 15: 169-171, 2007
La grippe espagnole (1918-1919) dans les journaux français
Authors: Bouron Françoise
Published: March 2009

La grippe espagnole (1918-1919) dans les journaux français La grippe espagnole (1918-1919) a fait plus de 20 millions de morts à travers le monde... plus que la Première Guerre mondiale. Et pourtant, pendant plusieurs mois, les journaux français restent silencieux. Mais il est vrai que la grippe fait moins peur que le choléra ou la peste, et que les journaux ont d’autres priorités en cette année 1918. Il faudra attendre octobre 1918 pour trouver dans la presse, et presque quotidiennement cette fois, des articles qui publient des conseils de médecins et font état des chiffres de la grippe.
Invasion ou libération ?
Authors: Bègue Sandrine
Published: March 2009

Invasion ou libération ? Quatorze années d’impasse diplomatique sur le départ portugais de la côte occidentale indienne auront finalement convaincu Nehru de risquer sa réputation pacifiste sur la scène internationale en prenant par les armes les établissements de Goa, Daman et Diu. Lancée à l’aube du 18 décembre 1961, cette opération militaire d’envergure contre trois poussières d’Empire illustre l’ambiguïté d’une décolonisation que le Pandit s’efforce parallèlement d’inscrire, auprès de la communauté internationale, dans une démarche libératrice attendue. L’analyse de cette fameuse journée du 18 décembre proposée ici s’attachera ainsi à saisir la réalité d’un gouvernement colonial agonisant, abandonné de la métropole et n’ayant survécu à Goa qu’à travers le contrat tacite passé avec une population locale attachée au maintien de ses particularismes culturels.
Un droit de gauche ?
Authors: Israël Liora
Published: March 2009

Résumé Cet article porte sur les nouvelles formes d'engagement politiques et professionnels des juristes de gauche dans les « années 68 ». Saisis à partir des événements eux-mêmes, en tant qu'ils ont aussi concerné des juristes (comme défenseurs et comme membres de l'Université notamment), il prend en compte les mises en formes politiques du droit caractéristiques de la période. Ces engagements se sont traduits à différents niveaux : par la création de syndicats d'avocats ou de magistrats ; via la constitution d'organisations contestataires ou critiques fondées pour tout ou partie sur des juristes ; à travers la remise en cause des pratiques professionnelles classiques des avocats, par exemple avec le développement des boutiques de droit. Nous montrerons comment ces engagements et ces pratiques ont contribué à remettre en cause et à transformer partiellement les modèles professionnels, et symétriquement comment, à travers l'engagement de ces juristes, le droit s'est intégré dans les formes de contestation propres aux années 70.
Activités de conception et créativité : de l'analyse des facteurs cognitifs à l'assistance aux activités de conception créatives
Authors: Bonnardel Nathalie
Published: March 2009

RÉSUMÉ Cet article propose un nouvel éclairage des activités de conception non routinières. L’idée défendue est qu’elles se situent sur un continuum allant des activités créatives mineures aux activités créatives majeures. De ce fait, la créativité est comparée aux activités de conception non routinières. Cela permet de caractériser les principaux processus cognitifs mis en œuvre dans les situations créatives. Des conditions stimulant l’émergence d’idées créatives de la part de concepteurs sont ensuite identifiées au moyen de résultats expérimentaux. Sur de telles bases, ont été développés des systèmes informatiques qui semblent particulièrement appropriés pour favoriser les activités de conception créatives. Ainsi, conformément à une approche d’ergonomie cognitive, la compréhension des facteurs cognitifs impliqués dans les activités de conception créatives contribue à la proposition de modalités d’assistance à ces activités.
Entre contraintes ergonomiques, créativité et esthétique : rôle d'un système à base de connaissances sur l'activité des concepteurs web
Authors: Chevalier Aline , Fouquereau Nicolas , Vanderdonckt Jean
Published: March 2009

RÉSUMÉ Les concepteurs de sites web doivent créer des sites qui répondent à la fois aux besoins du commanditaire du site et des futurs utilisateurs, ce qui se traduit, notamment, par la gestion de différentes contraintes liées à ces deux points de vue (commanditaire et utilisateurs). En ce qui concerne les besoins des utilisateurs, des recherches récentes ont montré que les concepteurs rencontrent des difficultés pour tenir compte des besoins des futurs utilisateurs. Pour aider les concepteurs à considérer le point de vue du futur utilisateur, nous avons mis à leur disposition un système à base de connaissances ergonomiques à la conception. Cette étude visait à déterminer l’impact de ce type d’aide sur l’activité cognitive des concepteurs ainsi que sur la qualité ergonomique et l’esthétique de leurs productions. Les résultats montrent que l’utilisation de l’outil encourage de façon indirecte les concepteurs à développer une activité créative centrée utilisateurs, sans pour autant nuire aux caractéristiques esthétiques et l’innovation de leurs productions.
La prédication seconde en français : essai de mise au point
Authors: Havu Eva , Pierrard Michel
Published: March 2009

Résumé La prédication seconde a fait l’objet de diverses tentatives de définition de la catégorie et de nombreuses études ont été menées sur des tours particuliers qui peuvent y être rattachés. L’examen des principales contributions sur la question nous a tout d’abord permis de dégager six traits récurrents généralement associés à la prédication seconde : l’instauration d’un lien prédicatif et l’absence d’une forme verbale (conjuguée) (syntaxe interne), l’établissement d’un rapport de dépendance de préd2 envers la prédication régissante et l’intégration syntaxique de préd2 dans celle-ci (syntaxe externe), ainsi que la position périphérique de préd2 par rapport à la structure argumentale de l’énoncé et l’apport de sens facultatif de préd2 (caractère accessoire de préd2 ). Dans un second temps, nous avons confronté les tours répertoriés à ces traits caractérisateurs, ce qui nous a permis de constater qu’aucun de ces tours ne répond pleinement à l’ensemble des traits. A partir de ces observations, nous discutons diverses questions : le caractère fermé de la catégorie de la prédication seconde, l’extension de son domaine et l’affinement de la description de certains tours particuliers.
Les formes verbales en -ant et la prédication seconde
Authors: Halmøy Odile
Published: March 2009

Résumé Les formes verbales en - ant du français [FV- ant ], gérondif et participe présent, subordonnées syntaxiquement à une prédication première ou à un élément de cette prédication, sont à considérer comme des représentants de la prédication seconde. Notre propos ici est de cerner davantage, en l’illustrant par des exemples, le comportement spécifique des [FV- ant ], selon leur fonction syntaxique, leur incidence - nominale, verbale, endophrastique ou exophrastique -, leur place par rapport à leur support, leur caractère lié ou détaché, leur apport informationnel et leur rôle discursif.
L'apposition : une construction multiforme
Authors: Caddéo Sandrine
Published: March 2009

Résumé La description de quelques nouvelles configurations à détachement conforte l’idée déjà présente chez Van den Bussche (1988) que certains types de segments apposés se comportent comme de véritables compléments adnominaux dont la constitution est parfois prédictible puisque contrainte par les traits syntactico-sémantiques du support et la contiguïté (quasi-) obligatoire. Il s’agit généralement de la catégorie des noms. D’autres types dits « détachés » bénéficient, eux, d’une relative liberté quant à leur forme et leur position. Le pronom non clitique, les groupes à spécifieurs (avec adverbes, prépositions, etc.) et la dislocation qualitative selon l’étiquette de Milner (1973) en font partie. Le lien avec le support s’établit dans un premier temps par les effets sémantiques qu’ils apportent : focalisation, partition, effet paradigmatisant, etc.
Les participes passés et la prédication seconde : les constructions en de du type Elle a un article de terminé
Authors: Lagae Véronique
Published: March 2009

Résumé Cette contribution vise à approfondir l’étude des structures existentielles à prédication seconde comportant de + adjectif ( Il y a une place de libre ) en traitant un aspect peu étudié, à savoir l’usage de participes passés comme prédicat second ( Il y a un verre de cassé ). L’étude met en évidence un certain nombre de propriétés qui opposent les deux séries de formes. On constate en particulier qu’en comparaison avec les adjectifs, les participes passés sont soumis à des contraintes de nature différente, essentiellement aspectuelle, puisque seuls sont acceptables les participes passés de verbes processifs téliques pouvant constituer une forme résultative avec être ( Un verre est cassé ). À cela s’ajoutent des phénomènes d’interférence avec le choix du verbe et de l’aspect verbal, ainsi que des différences d’interprétation.
Les quantifieurs flottants sont des attributs totalisants
Authors: Larrivée Pierre
Published: March 2009

Résumé Cette contribution avance que les quantifieurs flottants (QF) sont des attributs, les faisant relever de la problématique plus générale de la prédication seconde. La normalisation du statut grammatical de ces items amène à explorer l’extension de la classe qu’ils constituent. Cette classe est étendue à ensemble, tous (les) deux , seuls par certaines études, et la nôtre entend montrer que l’un l’autre , eux-mêmes , eux autres notamment ont les comportements qui les y apparentent. Si ces expressions ont dans l’emploi flottant fonction d’attribut, il faut se demander quelle propriété elles confèrent au nominal auquel elles renvoient. Cette propriété est d’indiquer la situation de l’intégralité des occurrences de l’ensemble, situation quantitative, présentative ou contrastive, distributive, globalisante ou réflexive ; une partition exprimable directement en anglais ( The guests were some of them condemning the countess ) étant indiquée par le biais d’une préposition en français ( Les invités ont pour quelques-uns d’entre eux condamné la comtesse ). Tous les membres de l’ensemble argument se trouvent concernés par l’événement prédicat, voilà l’indication qui constitue la raison d’être de ces attributs quantitatifs.
Carbon Nanotubes and Nanocomposites for Electrical and Thermal Applications
Authors: Wang Wei , Lu Fushen , Veca Lucia Monica , Meziani Mohammed J. , Wang Xin , Cao Li , Gu Lingrong , Sun Ya‐Ping
Published: March 2009

The extraordinary electrical and thermal properties of individual carbon nanotubes have prompted predictions on their potentials for ultimately forming polymeric nanocomposites. A significant barrier for the predicted nanocomposites is the severe bundling and insolubility of carbon nanotubes. Chemical modification and functionalization have been demonstrated as being effective in the debundling and solubilization of carbon nanotubes for their homogeneous dispersion into polymer matrices for desired high‐quality nanocomposites. More elegant is the approach to use polymers that are structurally identical or maximally similar to the matrix polymers in the nanotube functionalization to ensure full compatibility of the functionalized nanotubes with the corresponding polymer matrix. Several representative examples are presented, along with discussion on the benefits and issues concerning the polymeric nanocomposites thus obtained. For superior electrical properties, there is experimental evidence suggesting that the nanotube dispersion in the polymer matrix plays an important role. More promising is the use of separated metallic carbon nanotubes for a much enhanced performance in conductive nanocomposites and in related applications, such as transparent conductive films. For highly thermal conductive polymeric nanocomposites, on the other hand, the feasibility of using carbon nanotubes to achieve the desired performance has yet to be convincingly demonstrated experimentally. Nevertheless, the available results do suggest significant effects of the nanotube dispersion and alignment on thermal conductivities of the nanocomposites.
A Mild, One‐Pot Synthesis of Arylamines via Palladium‐ Catalyzed Addition of Aryl Aldehydes with Amines and Arylboronic Acids in Water
Authors: Yu Ajuan , Wu Yangjie , Cheng Baoli , Wei Kun , Li Jingya
Published: March 2009

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A mild, one‐pot synthesis of diarylmethylamines via the palladium‐catalyzed addition of aryl aldehydes with amines and arylboronic acids is reported. Best results were obtained in neat water with ammonium chloride as additive, affording diarylmethylamine derivatives as the main products.
Multiple joint dislocations: An additional skeletal finding in Lowry–Wood syndrome?
Authors: Magnani Cinzia , Tedesco Salvatore Antonio , Dallaglio Sara , Sommi Marcello , Bacchini Ermanno , Vetro Annalisa , Zuffardi Orsetta , Bevilacqua Giulio
Published: March 2009

We report on the case of a 17‐year‐old boy with clinical features compatible with Lowry–Wood syndrome: microcephaly, short stature, multiple epiphyseal dysplasia, tapetoretinal degeneration, and mental retardation. Bilateral restricted elbow extension, knock knees and hip dislocation were also present. Radiographs showed evidence of radial dislocation due to the absence of the radial heads, lateral dislocation of both patellae, multiple epiphyseal dysplasia that was more severe at the proximal femoral epiphyses, and dislocation of both hips with severe hip dysplasia. The patient developed a behavioral disorder at age 15. Conventional karyotyping was normal (46,XY). Molecular karyotyping, performed through array‐based competitive genomic hybridization, showed copy number variants that were probably benign. We suggest that multiple joint dislocations, including the patellae, may be a sign of Lowry–Wood syndrome. © 2009 Wiley‐Liss, Inc.
The feeding ecology and activity budget of proboscis monkeys
Authors: Matsuda Ikki , Tuuga Augustine , Higashi Seigo
Published: March 2009

A group of proboscis monkeys (Nasalis larvatus) consisting of an alpha‐male, six adult females, and several immatures was observed from May 2005–2006. We collected over 1,968 hr of focal data on the adult male and 1,539 hr of focal data on the six females in a forest along the Menanggul River, Sabah, Malaysia. Availability and seasonal changes in plant species consumed by the focal monkeys were determined by vegetation surveys carried out across an area of 2.15 ha along 200–500 m trails in riverine forest. A total of 188 plant species were consumed by the focal monkeys. The activity budget of members of our study group was 76.5% resting, 19.5% feeding, and 3.5% moving. Young leaves (65.9%) and fruits (25.9%) accounted for the majority of feeding time. Over 90% of fruit feeding involved the consumption of unripe fruits and in the majority of case both the fruit flesh and seeds were eaten. Although fruit eating was rare in some months, during other times of the year time fruit feeding exceeded the time devoted to young leaves. We found that monthly fruit availability was positively related to monthly fruit eating and feeding activity, and seasonal fluctuations in dietary diversity were significantly affected by fruit eating. These results suggest that fruit availability and fruit‐eating behaviors are key factors that influence the activity budget of proboscis monkeys. Earlier assumptions that colobine monkeys are obligate folivores do not apply well to proboscis monkeys and certain other colobines. Our findings may help contribute to a better understanding of the dietary adaptations and feeding ecology of Asian colobines. Am. J. Primatol. 71:478–492, 2009. © 2009 Wiley‐Liss, Inc.
Genetic continuity after the collapse of the Wari empire: Mitochondrial DNA profiles from Wari and post‐Wari populations in the ancient Andes
Authors: Kemp Brian M. , Tung Tiffiny A. , Summar Marshall L.
Published: March 2009

The Wari empire flourished in the central, highland Peruvian Andes from AD 600–1000, and although the events that led to its demise are unknown, archaeological evidence indicates that Wari control waned at the end of the first millennium. Here, we test the hypothesis that, despite the major shift in social and political organization at the fall of the Wari empire, the mitochondrial DNA (mtDNA) composition of populations from the Ayacucho Basin, the former imperial heartland of the empire, remained essentially unchanged. Results show that mtDNA haplogroup frequencies among the Wari and post‐Wari groups differ, but the difference is not statistically significant (χ2 = 5.886, df = 3, P = 0.1172). This is the first study in the Andes to use haplotypic data to evaluate the observed genetic distance between two temporally distinct prehispanic populations (FST = 0.029) against modeled expectations of four possible evolutionary scenarios. None of these simulations allowed the rejection of continuity. In total, at both the haplogroup and haplotype levels these data do not allow us to reject the hypothesis that post‐Wari individuals sampled in this study are the maternal descendants of those sampled from the Wari era site of Conchopata. However, genetic homogeneity in the mitochondrial gene pool, as seen in the late prehispanic southern Andes, may also characterize our study region. But, prior to this research, this was unknown. If our new data show mtDNA homogeneity, then this could limit the detection of female migration if, in fact, it occurred. Nonetheless, the novel mtDNA data presented here currently do not support the hypothesis that there was an influx of genetically distinct females into the former Wari heartland after the Wari collapse. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.
Targeting Bone Metastases with a Bispecific Anticancer and Antiangiogenic Polymer–Alendronate–Taxane Conjugate
Authors: Miller Keren , Erez Rotem , Segal Ehud , Shabat Doron , Satchi‐Fainaro Ronit
Published: March 2009

Ein polymeres Therapeutikum für die kombinierte Antikrebs‐ und antiangiogenetische Therapie inhibiert die Proliferation von Prostatakarzinomzellen sowie die Proliferation, Migration und Röhrenbildung von Endothelzellen. Das Nanokonjugat besteht aus einem N‐(2‐Hydroxypropyl)methacrylamid(HPMA)‐Copolymer, dem Bisphosphonat Alendronat (zur Ansteuerung von Knochengewebe) und dem Chemotherapeutikum Paclitaxel (PTX), das durch Cathepsin B abgespalten wird (siehe Schema).

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Enhanced Hydrogen Storage by Palladium Nanoparticles Fabricated in a Redox‐Active Metal–Organic Framework
Authors: Cheon Young Eun , Suh Myunghyun Paik
Published: March 2009

Richtig schnell: Palladiumnanopartikel (PdNPs) wurden einfach durch Eintauchen von {[Zn3(ntb)2(EtOH)2]⋅4 EtOH}n (1) in eine MeCN‐Lösung von Pd(NO3)2 bei Raumtemperatur ohne Zugabe eines Reduktionsmittels hergestellt. Mit 3 Gew.‐% PdNPs@[1]0.54+(NO3−)0.54 ist die H2‐Aufnahme gegenüber der von [Zn3(ntb)2]n sowohl bei 77 K und 1 bar als auch bei 298 K und hohen Drücken (siehe Bild) deutlich erhöht (rote bzw. schwarze Kurve). ntb=4,4′,4′′‐Nitrilotrisbenzoat.

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PELDOR Spectroscopy Distance Fingerprinting of the Octameric Outer‐Membrane Protein Wza from Escherichia coli.
Authors: Hagelueken Gregor , Ingledew W. John , Huang Hexian , Petrovic‐Stojanovska Biljana , Whitfield Chris , ElMkami Hassane , Schiemann Olav , Naismith James H.
Published: March 2009

Fingerabdruck eines Membranproteins: Durch gepulste Elektronendoppelresonanz(PELDOR)‐Spektroskopie wurde für das Periplasma des octameren Membranprotein‐Komplexes Wza aus E. coli ein detaillierter Abstands‐„Fingerabdruck“ erhalten, der mit Daten der Kristallstruktur in Einklang ist. Die Resultate bilden die Grundlage für eine Untersuchung von Konformationsänderungen bei der Wechselwirkung mit anderen Proteinen.

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Gas‐Phase Synthesis and Reactivity of the Lithium Acetate Enolate Anion, −CH2CO2Li
Authors: Meyer Matthew M. , Khairallah George N. , Kass Steven R. , O'Hair Richard A. J.
Published: March 2009

Protonenverlust im Flug: Das Lithiumacetat‐Enolation, ein prototypisches Lithiumsalz eines in α‐Stellung deprotonierten Carboxylats, wurde in der Gasphase durch Elektrosprayionisation (ESI) und stoßinduzierte Ionisation (CID) hergestellt. Seine Struktur, Reaktivität und Energetik werden ebenso vorgestellt wie die Resultate von Rechnungen auf hohem Niveau.

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Nonisothermal decomposition kinetics of nylon 1010/POSS composites
Authors: Yu Haiyang , Ren Wentan , Zhang Yong
Published: March 2009

The thermal stability of nylon 1010/polyhedral oligomeric silsesquioxane (POSS) composites prepared by melt blending was investigated with thermogravimetric analysis. The octavinyl POSS (vPOSS) and epoxycyclohexyl POSS (ePOSS) were used, and it was found that nylon/vPOSS composites have higher integral procedure decomposition temperature and char yield at 800°C than nylon/ePOSS composites. The Doyle–Ozawa (model‐free) and Friedman (model‐fitting) methods were used to characterize the nonisothermal decomposition kinetics of nylon 1010 and its composites. The activation energy (Ea), reaction order (n), and the natural logarithm of frequency factor of nylon 1010 were 267 kJ/mol, 1.0, and 47 min−1, respectively, in nitrogen. After the addition of POSS, the Ea of nylon 1010 considerably increased, whereas n had less change. The Ea steadily increased with increasing conversion and with increasing heating rate. The lifetime of nylon 1010 and its composites decreased with increasing temperature. At a given temperature, POSS significantly prolonged the lifetime of nylon 1010. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Studies on preparation of PGMA/Al2O3 and its effect on impact strength of epoxy resin
Authors: Wang Ruixin , Gao Baojiao , Zhang Yan , Chen Limei
Published: March 2009

In this article, two kinds of methods for grafting polyglycidyl methacrylate (PGMA) onto Al2O3 surface by the radical polymerization initiated by peroxide groups and double bond groups, respectively, were investigated. In the first method, peroxide groups, as initiators, were immobilized onto the Al2O3 surface. Then, GMA was polymerized on Al2O3 under the radicals decomposed by peroxide groups, and PGMA was grafted onto Al2O3. But in the second method, 3‐methacryloylpropyl trimethoxysilane was chemically bonded onto the Al2O3 surfaces firstly to introduce double bonds. Secondly, the copolymerizations between the immobilized double bonds and the monomer GMA were performed, homopolymerizations of GMA followed, and finally PGMA was grafted to the Al2O3 surfaces. The effects of grafting methods on grafting degree were examined mainly. At the same time, the effects of different grafting conditions on the grafting degree were researched. Furthermore, the effect of the grafted particles PGMA/Al2O3 on impact strength of the epoxy composites was studied. It was found that the grafting degree achieved by the first method was much higher than that by the second, and the grafting degree can reach about 54%. Moreover, the impact strength of epoxy composites containing PGMA/Al2O3 particles were improved largely, and which increased with the grafting degree. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Mechanical relaxation of medical grade UHMWPE of different crosslink density as prepared by electron beam irradiation
Authors: Göschel Ulrich , Ulrich Christian
Published: March 2009

Dynamic mechanical thermal analysis (DMTA) has been applied on medical grade ultra high molecular weight polyethylene of different crosslink density as prepared by electron beam irradiation to probe for contributions from crosslinking as well as crystallization. The crosslinking proceeds at a crystalline structure with a crystallinity about 50%. With increasing irradiation dose from 0 to 110 kGy, the molar mass between adjacent crosslinks decreases significantly to reach 3170 g/mol at lowest, whereas the crystallite thickness changes and new thin lamellae grow at almost constant degree of crystallinity. From DMTA in the entire temperature range from −150 to +140°C and the angular frequency range from 0.6 to 135.4 Hz, three relaxation processes γ, β, and α of different temperature position and activation energy are distinguished. The corresponding chain mobility has been discussed as a sensitive discriminator for the coexisting crosslinked and lamellar phases showing the same dimension of a couple of 10 of nanometres. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
The study on poly(ether sulfone) modified cyanate ester resin and epoxy resin cocuring blends
Authors: Zhan Guozhu , Hu Sheng , Yu Yingfeng , Li Shanjun , Tang Xiaolin
Published: March 2009

Poly(ether sulfone) terminated with phenolic hydroxyl groups modified cyanate ester resin and epoxy resin cocuring blends were investigated by differential scanning calorimetry, Fourier transform infrared spectroscopy, scanning electron microscopy, rheometry, and mechanical properties measurement. The results suggested that poly (ether sulfone) (PES) could accelerate the polycyclotrimerization reaction of cyanate ester and cocuring processes between cyanate ester and epoxy of modified blends because of the presence of phenolic hydroxyl groups at the end of the PES molecules. It was found that the evolution of the morphologies and complex viscosities of the modified blends sensitive to molecular weight and content of PES, the tensile strength and elongation at break of the modified blends were correlated with the morphologies of modified blends. Moreover, the evolution of complex viscosities of the modified blends also showed an exponential growth at the early stage of phase separation, which demonstrated experimentally that the coarsening processes of droplets of bisphenol‐A dicyanate and diglycidyl ether of bisphenol A and the final morphologies obtained in the blends modified with PES were affected by viscoelastic behavior. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Influence of oxygen plasma treatment on interfacial properties of poly(p‐phenylene benzobisoxazole) fiber‐reinforced poly(phthalazinone ether sulfone ketone) composite
Authors: Zhang Chengshuang , Chen Ping , Sun Baolei , Lu Chun , Zhang Xiangyi , Liu Dong
Published: March 2009

The influence of oxygen plasma treatment on both surface properties of poly(p‐phenylene benzobisoxazole) (PBO) fibers and interfacial properties of PBO fiber reinforced poly(phthalazinone ether sulfone ketone) (PPESK) composite were investigated. Surface chemical composition, surface roughness, and surface morphologies of PBO fibers were analyzed by X‐ray photoelectron spectroscopy (XPS), Atomic force microscopy (AFM), and scanning electron microscopy (SEM), respectively. Surface free energy of the fibers was characterized by dynamic contact angle analysis (DCAA). The interlaminar shear strength (ILSS) and water absorption of PBO fiber‐reinforced PPESK composite were measured. Fracture mechanisms of the composite were examined by SEM. The results indicated that oxygen plasma treatment significantly improved the interfacial adhesion of PBO fiber‐reinforced PPESK composite by introducing some polar or oxygen‐containing groups to PBO fiber surfaces and by fiber surface roughening. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation and electrochemical studies of layered PANI/HNb3O8 nanocomposite
Authors: Yang Gang , Liu Yuge , Hou Wenhua , Ji Hongmei , Li Yuhong
Published: March 2009

Aniline monomers could be easily inserted into and polymerized within the interlayers of HNb3O8. The conformation and electrochemical properties of the resulting nanocomoposites were discussed in detail. Two different mechanisms were proposed for the polymerization of monomers within the confined interlayers initiated by chemical oxidants and microwave irradiation, respectively. The analyses of thermogravimetric/differential scanning calorimetric analyses, X‐ray diffraction, and Fourier transform infrared spectra indicated that the aromatic rings of the interlayered polyaniline (PANI) could be parallel with or perpendicular to the inorganic slabs, and the interlayered PANI molecules were emeraldine salt and protonated by the protons of layered inorganic acid host. The cyclic voltammetry revealed that the properties of the layered host and the interlayer height have an effect on the redox behavior of the corresponding nanocomposites. Compared with the nanocomposites in which the aromatic rings were parallel with the inorganic slabs, the nanocomposites in which the aromatic rings were perpendicular to the slabs demonstrated a higher conductivity and electrochemical activity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Influence of silicone phosphate on the transesterification in PBT/PC blends
Authors: Lei Caihong , Chen Dahua , Gou Yuhui , Huang Weiliang
Published: March 2009

Because of the transesterification reaction between poly(butylene terephthalate) (PBT) and polycarbonate (PC), the crystallization behavior and thermal‐resistant properties of the blend have been known to be decreased. Therefore it is of importance to control the transesterification degree in PBT/PC blends. In this article, the effect of silicone phosphate on the transesterification reaction between PBT and PC was studied using differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR), and infrared spectroscopy (IR). It was found that the crystallization temperature of PBT/PC/silicone phosphate was 18.0°C higher than that of pure system, and the difference of the crystallization temperature between the first and secondary cooling cycles in DSC was 15.8°C lower than that of the pure system. IR results showed that both random and block copolymer existed in the stabilized system, and both IR and NMR results proved the decrease of the copolymer content by the introduction of silicone phosphate. Compared with that of the pure system, the Vicat soft temperature of the stabilized system was increased by 17.2°C. All the results showed that silicone phosphate was an effective inhibitor for the controlling of the transesterification reaction in PBT/PC blends. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Novel hydrogels based on itaconic acid and citraconic acid: Synthesis, metal ion binding, and swelling behavior
Authors: Jeria‐Orell Manuel , Pizarro Guadalupe del C. , Marambio Oscar G. , Geckeler Kurt E.
Published: March 2009

Several copolymer hydrogels were prepared from radical copolymerization of 2‐hydroxypropyl methacrylate (HPMA) with itaconic acid (IA) and also with citraconic acid (CA) by using different feed ratios. The copolymers were characterized by FTIR, 1H‐NMR, and 13C‐NMR spectroscopy as well as by thermal analysis. The swelling process of the different hydrogels immersed in water at different pH has been studied, and also the swelling of the hydrogels loaded with metal ions (Pb2+, Cd2+) was investigated. The metal‐binding properties were studied by using the liquid‐phase polymer‐based retention technique, including studies on the influence of pH on the binding process. The efficiency of these hydrogels for the recovery of metal ions in solution was determined by atomic absorption spectroscopic analysis. The thermal characteristics of these copolymers were studied by using differential scanning calorimetry and thermogravimetric analysis in nitrogen atmosphere. Accordingly, the gels loaded with metal ions showed a slight increase of the thermal decomposition temperature when compared with the pristine gels. The copolymer gel HPMA‐co‐CA showed a single glass transition temperature, whereas for the copolymer systems, HPMA‐co‐IA, only the copolymers loaded with Cd2+ ions showed a glass transition temperature. The morphology of film produced from the copolymers was investigated by scanning electron microscopy, revealing generally smooth surfaces. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Digestive proteolysis organization in two closely related Tenebrionid beetles: red flour beetle (Tribolium castaneum) and confused flour beetle (Tribolium confusum)
Authors: Vinokurov K.S. , Elpidina E.N. , Zhuzhikov D.P. , Oppert B. , Kodrik D. , Sehnal F.
Published: March 2009

The spectra of Tribolium castaneum and T. confusum larval digestive peptidases were characterized with respect to the spatial organization of protein digestion in the midgut. The pH of midgut contents in both species increased from 5.6–6.0 in the anterior to 7.0–7.5 in the posterior midgut. However, the pH optimum of the total proteolytic activity of the gut extract from either insect was pH 4.1. Approximately 80% of the total proteolytic activity was in the anterior and 20% in the posterior midgut of either insect when evaluated in buffers simulating the pH and reducing conditions characteristic for each midgut section. The general peptidase activity of gut extracts from either insect in pH 5.6 buffer was mostly due to cysteine peptidases. In the weakly alkaline conditions of the posterior midgut, the serine peptidase contribution was 31 and 41% in T. castaneum and T. confusum, respectively. A postelectrophoretic peptidase activity assay with gelatin also revealed the important contribution of cysteine peptidases in protein digestion in both Tribolium species. The use of a postelectrophoretic activity assay with p‐nitroanilide substrates and specific inhibitors revealed a set of cysteine and serine endopeptidases, 8 and 10 for T. castaneum, and 7 and 9 for T. confusum, respectively. Serine peptidases included trypsin‐, chymotrypsin‐, and elastase‐like enzymes, the latter being for the first time reported in Tenebrionid insects. These data support a complex system of protein digestion in the Tribolium midgut with the fundamental role of cysteine peptidases. © 2009 Wiley Periodicals, Inc.
Efficacy of repeat isolated limb infusion with melphalan and actinomycin D for recurrent melanoma
Authors: Kroon Hidde M. , Lin D‐Yin , Kam Peter C. A. , Thompson John F.
Published: March 2009

BACKGROUND:

Isolated limb infusion (ILI) is an effective and minimally invasive treatment option for delivering regional chemotherapy in patients with metastatic melanoma confined to a limb. Recurrent or progressive disease after an ILI, however, presents a challenge for further treatment. The value of repeat ILI in this situation has not been well documented.

METHODS:

Forty‐eight patients were identified who had been treated with a repeat ILI. In all patients, a cytotoxic combination of melphalan and actinomycin D was used.

RESULTS:

The median time between the 2 procedures was 11 months. The complete response (CR) rate after repeat ILI was 23%, compared with 31% after the initial ILI (P = .36). The overall response was 83%, compared with 75% after the first procedure (P = .32). The median duration of response was 11 months (10 months for patients with CR; P = .80), and median survival was 38 months. In those patients achieving a CR, the median survival was 68 months (P = .003). Toxicity after repeat ILI was increased, with 20 patients experiencing Wieberdink grade III limb toxicity (considerable erythema and edema with blistering) and 5 patients experiencing grade IV toxicity (threatened or actual compartment syndrome), whereas after the initial ILI these toxicity grades occurred in 14 patients and 1 patient, respectively (P = .03). No patient experienced grade V toxicity (requiring amputation).

CONCLUSIONS:

Repeat ILI is an attractive treatment option to achieve limb salvage in patients with inoperable recurrent or progressive melanoma after a previous ILI. It can be associated with significant short‐term regional toxicity, but is well tolerated by most patients, with satisfactory response rates. Cancer 2009. © 2009 American Cancer Society.
A novel hypothesis on the sensitivity of the fecal occult blood test
Authors: Lansdorp‐Vogelaar Iris , van Ballegooijen Marjolein , Boer Rob , Zauber Ann , Habbema J. Dik F.
Published: March 2009

BACKGROUND:

Estimates of the fecal occult blood test (FOBT) (Hemoccult II) sensitivity differed widely between screening trials and led to divergent conclusions on the effects of FOBT screening. We used microsimulation modeling to estimate a preclinical colorectal cancer (CRC) duration and sensitivity for unrehydrated FOBT from the data of 3 randomized controlled trials of Minnesota, Nottingham, and Funen. In addition to 2 usual hypotheses on the sensitivity of FOBT, we tested a novel hypothesis where sensitivity is linked to the stage of clinical diagnosis in the situation without screening.

METHODS:

We used the MISCAN‐Colon microsimulation model to estimate sensitivity and duration, accounting for differences between the trials in demography, background incidence, and trial design. We tested 3 hypotheses for FOBT sensitivity: sensitivity is the same for all preclinical CRC stages, sensitivity increases with each stage, and sensitivity is higher for the stage in which the cancer would have been diagnosed in the absence of screening than for earlier stages. Goodness‐of‐fit was evaluated by comparing expected and observed rates of screen‐detected and interval CRC.

RESULTS:

The hypothesis with a higher sensitivity in the stage of clinical diagnosis gave the best fit. Under this hypothesis, sensitivity of FOBT was 51% in the stage of clinical diagnosis and 19% in earlier stages. The average duration of preclinical CRC was estimated at 6.7 years.

CONCLUSIONS:

Our analysis corroborated a long duration of preclinical CRC, with FOBT most sensitive in the stage of clinical diagnosis. Cancer 2009. © 2009 American Cancer Society.
Patterns of treatment for early stage breast cancers at the M. D. Anderson Cancer Center from 1997 to 2004
Authors: Shen Yu , Dong Wenli , Feig Barry W. , Ravdin Peter , Theriault Richard L. , Giordano Sharon H.
Published: March 2009

BACKGROUND:

The objectives of this study were to examine the patterns of use for adjuvant therapy and the changes in surgical practice for patients with early stage breast cancer and to describe how recent large clinical trial results impacted the patterns of care at The University of Texas M. D. Anderson Cancer Center (MDACC).

METHODS:

The study included 5486 women who were diagnosed with stage I through IIIA breast cancer between 1997 and 2004 and received their treatment at MDACC. A chi‐square trend test and multivariate logistic regression model were used to assess changes in treatment patterns over time.

RESULTS:

Among lymph node‐positive patients, the use of anthracycline plus taxane chemotherapy increased from 17% in 1997 to 81% in 2004 (P < .001). Meanwhile, the use of anthracyclines without taxanes dropped from 76% to 20% (P < .001) between 1997 and 2000. For postmenopausal patients who received endocrine therapy, the use of tamoxifen was replaced increasingly by the use of aromatase inhibitors (from 100% on tamoxifen in 1997 to 14% in 2004; P < .001). The percentage of women who underwent initial sentinel lymph node biopsy increased significantly during the period from 1997 to 2004 (from 1.8% to 69.7%, respectively, among patients who underwent mastectomy; and from 18.1% to 87.1%, respectively, among patients who underwent breast‐conserving surgery; P < .001).

CONCLUSIONS:

The results from this study suggested that key findings from adjuvant therapy and surgical procedures from large clinical trials often prompt immediate changes in the patient care practices of research hospitals like MDACC. Cancer 2009. © 2009 American Cancer Society.
Evolution of Permanent Deformations (or Memory) in Nafion 117 Membranes with Changes in Temperature, Relative Humidity and Time, and Its Importance in the Development of Medium Temperature PEMFCs
Authors: Alberti G. , Narducci R.
Published: March 2009

An important problem for medium temperature polymer electrolyte fuel cells (MT PEMFCs) operating in the temperature range 90–140 °C is the short time‐life of proton conducting membranes. To shed some light on the empirical annealing treatments used for increasing the membrane durability, a systematic research on the effects of thermal treatments of Nafion 117 membranes was undertaken with the hope that the information obtained could be useful for a better understanding of the real limits for MT PEMFCs. Kinetic experiments showed that, for each couple of T–RH values, the water taken up from the membrane reaches a constant value only after long times of equilibration (≥200 h). Taking into account that the enlargements provoked by the water‐uptake remain as permanent deformations when the samples are cooled, it was found that the evolution of the deformations provoked by changes in temperature and RH can be conveniently estimated at 20 °C by determining the water taken up after equilibration in liquid water. By relating the counter‐elastic index of the matrix (nc(m)) to the extent of these deformations, a set of equations were obtained which allowed us to predict their evolution with changes of temperature and relative humidity. A good agreement with experimental values was found. The importance of this discovery for the development of MT PEMFCs is discussed.