bluuebunny/crossref_metadata_2025 huggingface dataset:
Solanum‐Alkaloide, I. Mitteil.: Solacaulin, ein neues Glykoalkaloid aus den Blättern von Solanum acaule
Authors: Schreiber Klaus
Published: May 2007

Aus den Blättern von Sol. acaule wurde ein neues Glykoalkaloid, Solacaulin, isoliert. Solacaulin liefert bei der Hydrolyse 1 Mol. Solanidin, 1 Mol. d‐Glucose und 2 Moll. d‐Xylose.
Polymethinfarbstoffe, IV. Mitteil.): Über Furyl‐pyrryl‐ und Furylindolyl‐methinfarbstoffe
Authors: Strell Martin , Kalojanoff Anton , Brem‐Rupp Luzie
Published: May 2007

Es werden unsymmetrische Methinfarbstoffe beschrieben, die durch Kondensation von α‐Furyl‐polyenalen mit Pyrrolen bzw. mit α‐Phenyl‐indol entstehen. Die Absorptionsspektren wurden qualitativ und z.Tl. quantitativ vermessen.
Notiz über Formazylkomplexe der Pyridin‐Reihe
Authors: Seyhan Muvaffak
Published: May 2007

Es wird eine neue Formazylverbindung beschrieben, welche an der Formazan‐Kette mit einer Pyridyl‐Gruppe substituiert ist und in o‐Stellung zu dieser Kette eine Carboxy‐Gruppe trägt. Die Verbindung liefert mit Uran‐und Kobaltsalzen tieffarbige Komplexe, bei denon eine Koordinationsstelle am Metall‐Atom durch den Ringstickstoff eines zweiten Formazylmoleküls besetzt ist.
tert.‐Butylester von Pyrrolcarbonsäuren
Authors: Treibs Alfred , Hintermeier Karl
Published: May 2007

Acetessigsäure‐tert.‐butylester läßt sich allgemein für Pyrrol‐Synthesen verwenden. Die tert.‐Butylestergruppe zerfällt katalytisch unter Bildung der entsprechenden Pyrrolcarbonsäuren, die thermisch decarboxyliert werden können.
Über Triphenyl‐phosphin‐methylene als olefinbildende Reagenzien (I. Mitteil.
Authors: Wittig Georg , Schöllkopf Ulrich
Published: May 2007

Bei der Umsetzung von Triphenyl‐phosphin‐methylen und seinen in der Methylengruppe substituierten Derivaten mit Aldehyden und Ketonen wird der doppelt gebundene Sauerstoff gegen die Methylenreste ausgetauscht, wobei Triphenyl‐phosphinoxyd und die entsprechenden ungesättigten Verbindungen entstehen. Der mit dieser neuen Methode sich abzeichnende präparative Fortschritt liegt darin, daβ die C=C–Bindung ohne Verschiebung am Ort der ursprünglichen C=O–Bindung ausgebildet wird.
Diazomethan als Oxydationsmittel und sein Verhalten gegen stabile Tautomere der Anthron‐Reihe
Authors: Arndt Fritz , Schlatter James M.
Published: May 2007

Anthron und Anthranol werden von Diazomethan im wesentlichen zu Dianthron oxydiert, daneben entsteht 9‐Methoxy‐anthracen. Dianthron und Dehydrodianthron reagieren nicht, Dianthranol wird in normaler Reaktion zu Dimethoxy‐dianthracen methyliert.
Über glykosidische Pflanzeninhaltsstoffe, VI. Mitteil.: Die Bitterstoffe der Gentianaceen
Authors: Korte Friedhelm
Published: May 2007

Es wird die Identität von Erytaurin, Gentiamarin und Swertiamarin mit Gentiopikrin nachgewiesen. Ferner entspricht das Gentiin dem Gentisin, welches als 1.7‐Dioxy‐3‐methoxy‐xanthon charakterisiert ist.
Über heterocyclische Siebenringsysteme, IV. Mitteil.): Synthesen und Eigenschaften von 4.5‐Benzo‐[hept‐1.2.6‐oxdiazinen]
Authors: Ried Walter , Stahlhofen Paul
Published: May 2007

Beim Behandeln der Oxime von o‐Acylamino‐carbonyl‐Verbindungen mit konz. Schwefelsäure tritt unter Wasserabspaltung Ringschluß zu einem heterocyclischen Siebenringsystem, das 2 Stickstoff‐Atome und 1 Sauerstoff‐Atom enthält, ein. Die Stabilität dieses sog. Hept‐oxdiazin‐Ringes ist abhängig von der Natur und Stellung etwaiger Substituenten. Die Siebenringstruktur wird bewiesen: 1. Bei der katalytischen Hydrierung erfolgt Ringverengerung zu substituierten 3.4‐Dihydro‐chinazolinen; 2. in Siebenstellung methylierte Hept‐oxdiazine sind zu Kondensationen mit aromatischen Aldehyden befähigt.
Die Konstitution des Homolycorins und des Lycorenins (VII. Mitteil. über Amaryllidaceen‐Alkaloide
Authors: Boit Hans‐G. , Paul Lieselotte , Stender Wolfgang
Published: May 2007

Durch die Oxydation von Lycorenin zu der Lacton‐Base Homolycorin wird für das erstere die Lactol‐Struktur I bestätigt und für das letztere die Konstitution II abgeleitet.
Über N‐Nitro‐pyrazole
Authors: Hüttel Rudolf , Büchele Friedrich
Published: May 2007

Als erste Vertreter von Nitraminen, die sich von Heterocyclen aromatischen Charakters ableiten, werden die N‐Nitro‐pyrazole hergestellt und untersucht.
Das Kondensationsprodukt C13H14O2 aus Salicylal‐aceton und Acetessigester, ein tricyclisches Keton
Authors: Kuhn Richard , Weiser Dieter
Published: May 2007

Die von T. A. Forster und I. M. Heilbron erhaltene Verbindung C13H14O2 ist nicht das Chromen VIII, sondern ein tricyclisches Keton der Formel V, das sich – vergleichbar dem Anhydrid der cis‐Hexahydro‐isophthalsäure – spannungsfrei konstruieren läßt.
Über pflanzliche Herzgifte, XXXI. Mitteil.1): Neue herzwirksame Verbindungen aus den Zwiebeln von Bowiea volubilis Harvey
Authors: Tschesche Rudolf , Sarau Hans‐Werner , Sellhorn Kurt
Published: May 2007

Es wird über die Isolierung von 4 neuen herzwirksamen Verbindungen aus den großen grünen Zwiebeln von Bowiea volubilis Harvey berichtet, von denen eine ein Thevetosid ist, alle übrigen aber wahrscheinlich Derivate eines noch unbekannten sauerstoffreichen Grundstoffes von 7 C‐Atomen sind. Es werden neue Namen für die isolierten Verbindungen vorgeschlagen.
Ein Beitrag zum Mechanismus der Kondensation von o‐Diaminen mit Alloxan und Dimethyl‐alloxan
Authors: Pfleiderer Wolfang
Published: May 2007

Während die Kondensationen von o‐Phenylendiamin und 4.5‐Diamino‐1.3‐dimethyl‐uracil mit Alloxan bzw. Dimethyl‐alloxan in saurem Medium nach dem gleichen Mechanismus ablaufen, findet in neutraler Lösung im Falle des Dimethyl‐alloxans primär eine Aufspaltung in Mesoxalsäure‐monomethylamid statt, das dann die Kondensationen eingeht. Bei Umsetzungen des Mesoxalsäure‐monomethylamids mit heterocyclischen o‐Diaminen, die verschieden stark basische Aminogruppen enthalten, können durch Variation der Reaktionsbedingungen die beiden möglichen Isomeren erhalten werden.
Aromatische Borverbindungen, V. Mitteil.1)
Authors: Neu Richard
Published: May 2007

Die Darstellung von Tetraphenyl‐diboroxyd und von Tetra‐p‐tolyl‐diboroxyd aus Phenyl‐ und p‐Tolyl‐magnesiumbromid und Borsäureester wird beschrieben.
Der Mechanismus der oxydo‐reduktiven Aminierung von α‐Ketoaldehyden
Authors: Wieland Theodor , Jaenicke Friedrich
Published: May 2007

Bei der Bildung von α‐Aminosäuren aus α‐Ketoaldehyden + NH3 in Gegenwart von Mercaptanen wird aus tritiumhaltigem Wasser kein isotoper Wasserstoff eingebaut und damit einer der in der vorherigen Mitteilung diskutierten Reaktionsmechanismen, Verschiebung eines Hydridions, als der richtige erkannt.
Die Reaktion von Äthylenoxyd mit Distickstofftetroxyd
Authors: Rossmy Gerd
Published: May 2007

Die Reaktion von N2O4 mit Äthylenoxyd in Chloroform‐Lösung führt nicht, wie bisher angenommen, zur Bildung von 2‐Nitro‐äthanolnitrat. Vielmehr entsteht in der Hauptsache Glykolnitrit‐nitrat, das sich zu Glykol‐mononitrat verseifen läßt. Auch Diäthylenglykolmononitrat ließ sich im Reaktionsprodukt nach der Verseifung nachweisen.
Über Selenensäuren, III. Mitteil.1): Bildung von Selenensäuren durch Reduktion von Seleninsäuren mittels Unterphosphoriger und Phosphoriger Säure
Authors: Rheinboldt Heinrich , Giebrecht Ernesto
Published: May 2007

Die Bedingungen werden ermittelt, unter denen o‐Nitro‐benzolseleninsäuren und Anthrachinon‐seleninsäure‐(1) durch Unterphosphorige Säure zu den entsprechenden Selenensäuren reduziert werden. Überschüssige Unterphosphorige Säure bewirkt wie Hydrazin2) und im Gegensatz zu Mercaptanen und Selenmercaptanen1) keine weitergehende Reduktion zu Diseleniden. Benzolseleninsäure und deren Abkömmlinge ohne o‐Nitrogruppen werden jedoch auch durch Unterphosphorige Säure zu Diseleniden reduziert. Phosphorige Säure reduziert, in stärker saurem Medium, erstere Seleninsäuren ebenfalls zu Selenensäuren und letztere zu Diseleniden, jedoch in beiden Fällen sehr unvollkommen.
Eine neue Synthese von homologen α‐Oxysäuren aus Carbonsäuren
Authors: Weygand Friedrich , Bestmann Hans Jürgen
Published: May 2007

Aus Carbonsäuren erhält man über die Diazoketone mit organischen Schwefelchloriden α‐Halbmercaptalchloride der α‐Ketoaldehyde, die als solche oder besser nach der Überführung in α‐Halbmercaptal‐acetoxy‐Verbindungen mit verd. Laugen α‐Oxysäuren liefern.
Synthesen von Pteridinen mit α‐Halogen‐α‐[aryl‐ bzw. alkyl‐mercapto]‐ketonen
Authors: Weygand Friedrich , Bestmann Hans Jürgen
Published: May 2007

Die aus Carbonsäuren leicht zugänglichen α‐Halogen‐α‐[aryl‐ bzw. alkyl‐mercapto]‐ketone ergaben bei der Kondensation mit 6‐Oxy‐2.4.5‐triamino‐pyrimidin Pteridine. Folsäure, Pteroinsäure und andere Pteridine lassen sich so gewinnen.
Die Infrarot‐ und Raman‐Spektren hochsymmetrischer Moleküle mit Urotropinstruktur
Authors: Mecke Reinhard , Spiesecke Hilmar
Published: May 2007

Es werden die Infrarot‐ und Raman‐Spektren des Urotropins, des Tetramethyl‐hexathia‐adamantans und des Adamantans diskutiert.
Lipid and Fatty Acid Composition of Diatoms Revisited: Rapid Wound‐Activated Change of Food Quality Parameters Influences Herbivorous Copepod Reproductive Success
Authors: Wichard Thomas , Gerecht Andrea , Boersma Maarten , Poulet Serge A. , Wiltshire Karen , Pohnert Georg
Published: May 2007

Lipid and fatty acid composition are considered to be key parameters that determine the nutritive quality of phytoplankton diets for zooplanktonic herbivores. The fitness, reproduction and physiology of the grazers are influenced by these factors. The trophic transfer of lipids and fatty acids from algal cells has been typically studied by using simple extraction and quantification approaches, which, as we argue here, do not reflect the actual situation in the plankton. We show that cell disruption, as it occurs during a predator's grazing on diatoms can drastically change the lipid and fatty acid content of the food. In some algae, a rapid depletion of polyunsaturated fatty acids (PUFAs) is observed within the first minutes after cell disruption. This fatty acid depletion is directly linked to the production of PUFA‐derived polyunsaturated aldehydes (PUA); these are molecules that are thought to be involved in the chemical defence of the algae. PUA‐releasing diatoms are even capable of transforming lipids from other sources if these are available in the vicinity of the wounded cells. Fluorescent staining reveals that the enzymes involved in lipid transformation are active in the foregut of copepods, and therefore link the depletion processes directly to food uptake. Incubation experiments with the calanoid copepod Temora longicornis showed that PUFA depletion in PUA‐producing diatoms is correlated to reduced hatching success, and can be compensated for by externally added single fatty acids.
Cycloaddition of CO2 to Epoxides Catalyzed by Polyaniline Salts
Authors: He Jinling , Wu Tianbin , Zhang Zhaofu , Ding Kunlun , Han Buxing , Xie Ye , Jiang Tao , Liu Zhimin
Published: May 2007

The catalytic activity of polyaniline‐HX (X=I, Br, Cl) (PANI‐HI, PANI‐HBr, PANI‐HCl) for the cycloaddition of CO2 to propylene oxide (PO) to produce propylene carbonate (PC) was studied for the first time. It was shown that all the PANI salts were active for the reaction, and PANI‐HI was most active and selective. On the basis of the preliminary results, the effect of the reaction conditions on the cycloadditions of CO2 to propylene oxide and epichlorohydrin was further investigated by using PANI‐HI as the catalyst. The results indicated that the optimized temperature was around 115 °C. The maxima occurred in yield versus pressure curves at about 5 MPa for both substrates. Complete conversion was achieved in 3 h for epichlorohydrin and 6 h for propylene oxide at 115 °C and 5 MPa. With propylene oxide as the substrate, the reusability of PANI‐HI was evaluated and no loss of catalytic activity was detectable after the catalyst had been reused five times. The catalyst was characterized by thermogravimetric analysis (TGA) and scanning electron microscopy (SEM), which provided further evidence for the high stability of the catalyst. We believe that the catalyst has great potential for industrial applications because it has some unusual advantages, such as its easy preparation, high activity, selectivity, stability, low cost, and simple separation from products.
High‐dose chemotherapy with autologous stem cell rescue followed by posterior fossa irradiation for local medulloblastoma recurrence or progression after conventional chemotherapy
Authors: Ridola Vita , Grill Jacques , Doz Francois , Gentet Jean‐Claude , Frappaz Didier , Raquin Marie‐Anne , Habrand Jean‐Louis , Sainte‐Rose Christian , Valteau‐Couanet Dominique , Kalifa Chantal
Published: May 2007

BACKGROUND

The objective of the current study was to determine the outcome of children with local recurrence or progression of medulloblastoma in patients who received high‐dose chemotherapy (HDC) and posterior fossa (PF) irradiation.

METHODS

HDC consisted in busulfan at a dose of 600 mg/m2 and thiotepa at a dose of 900 mg/m2 followed by autologous stem cells transplantation (ASCT). PF radiotherapy was delivered at doses from 50 grays (Gy) to 55 Gy on Day +70 after ASCT. Twenty‐seven patients developed local recurrence of an initially completely resected medulloblastoma. Twelve patients had local residual disease after surgery and were enrolled into the salvage protocol at the time of local disease progression under conventional chemotherapy.

RESULTS

Acute toxicity consisted mainly in hepatic veno‐occlusive disease (33% of patients) and bone marrow aplasia. Two toxic deaths (5%) from infections were reported. The 5‐year overall survival rate after this salvage treatment (OS5y) for the 39 children who were treated was 68.8% (95% confidence interval [95% CI], 53–81.2%). In the group of patients who were treated for local recurrence, the OS5y was 77.2% (95% CI, 58.3–89.1%). Patients with local residual disease who were treated at the time of disease progression had an OS5y after salvage treatment of only 50% (95% CI, 25.4–74.6%; P = .09).

CONCLUSIONS

The treatment strategy that was used in this study had manageable immediate toxicity and resulted in a high overall survival rate in the setting of young children with medulloblastoma who developed local recurrence or disease progression. Cancer 2007. © 2007 American Cancer Society.
Efficient truthful mechanisms for the single‐source shortest paths tree problem
Authors: Gualà L. , Proietti G.
Published: May 2007

Let a communication network be modeled by an undirected graph
$G=(V,E)$ of n nodes
and m edges, and assume that edges are controlled by
selfish agents, which privately hold the length of each owned
edge. In this paper we analyze the problem of designing a
truthful mechanism for computing one of the most popular network
topologies, i.e. the single‐source shortest paths
tree. More precisely, we study several realistic scenarios,
in which each agent can own either a single edge or multiple
edges of G. In particular, for the single‐edge
scenario, we show that in the utilitarian case the problem can be
efficiently solved in $O(mn \log{}\alpha(m,n))$ time, while in a meaningful
non‐utilitarian case, namely that in which agents'
valuation functions depend only on the edge lengths, it can be
solved in $O(m + n \log n)$
time. On the other hand, for the multiple‐edge scenario,
in the utilitarian case we show an $O(mn+n^2 \log n)$ time truthful
mechanism, while in the same non‐utilitarian case we
provide an n‐approximate truthful mechanism which
can be implemented in $O(m n \,\alpha(m,n))$ time. We also show that in the special
case in which, for every agent, the owned edges are all incident
to the same node, then this latter mechanism has an almost
optimal $O(m\,\alpha(m,n))$
runtime. Copyright © 2007 John Wiley & Sons, Ltd.
Version Vector Weighted Voting protocol: efficient and fault‐tolerant commitment for weakly connected replicas
Authors: Barreto João , Ferreira Paulo
Published: May 2007

Mobile and other loosely coupled environments call for decentralized optimistic replication protocols that provide highly available access to shared objects, while ensuring eventual consistency. We propose a protocol based on epidemic weighted voting for achieving such a goal with better availability than traditional primary commit approaches. We improve previous epidemic weighted voting solutions by allowing commitment of multiple, happened‐before related updates at a single distributed election round. We demonstrate that our protocol, in contrast to basic weighted voting solutions, achieves similar update commitment ratios to the primary commit alternative. The improvement over basic weighted voting is especially amplified with weaker replica connectivity, as in mobile and other loosely coupled environments. We support such claims by presenting comparison performance results obtained from side‐by‐side execution of reference protocols in a simulated environment. Copyright © 2007 John Wiley & Sons, Ltd.
Antioxidant activity of red wine phenolic extracts towards oxidation of corn oil
Authors: Lambropoulos Ioannis , Roussis Ioannis G.
Published: May 2007

The antioxidant activity of Xinomavro red wine phenolic extracts in corn oil stripped of tocopherols was evaluated. One wine extract, at 100 mg/L total phenolics, rich in phenolic acids and flavonols, inhibited the oxidation of corn oil stripped of tocopherols to a greater extent than butylated hydroxyanisole, at 200 mg/L. Moreover, another extract, at 100 mg/L total phenolics, rich in flavanols, flavonols and tyrosol, also exhibited high inhibitory action. The present results indicate that some red wine phenolics – such as phenolic acids, flavonols or flavanols – may be strong antioxidants in corn oil.
Oxygen and Temperature Control during the Cultivation of Microorganisms using Substrate Feeding
Authors: Vanags J. , Rychtera M. , Ferzik S. , Vishkins M. , Viesturs U.
Published: May 2007

Aerobic fermentation via substrate feeding controlled by O2 and temperature supplements the tools for the experimental and possibly industrial use. This substrate‐feeding algorithm was realized with the help of the flexible Bioprocess controller BIO‐2.
Effect of Selected Parameters of Lactose Hydrolysis in the Presence of β‐Galactosidase from Various Sources on the Synthesis of Galactosyl‐Polyol Derivatives
Authors: Klewicki R.
Published: May 2007

Galactosyl‐polyhydroxyalcohols are products of transgalactosylation occurring during lactose hydrolysis in the presence of polyols. Products of transgalactosylation (mainly galactooligosaccharides) are known for their health‐promoting properties. The aim of this research was to determine the conditions of the synthesis of selected gal‐polyols using enzymes from various sources: Kluyveromyces fragilis, Kluyveromyces lactis and Aspergillus oryzae. The highest amounts of galactosyl derivatives of polyol‐monomers (sorbitol, xylitol and erythritol), formed during the enzymatic hydrolysis of lactose with the use of the enzyme from K. lactis, were obtained using an initial solution of the molar ratio of lactose to polyol equal to 1:1.85. In the case of lactitol, this proportion amounted to 1:2.9. The best transgalactosylating properties in the course of the synthesis of gal‐sorbitol and gal‐erythritol were obtained with β‐galactosidase from K. fragilis; where the contents of galactosyl derivatives in dry matter accounted for 16.4 % [w/w] and 18.8 % [w/w], respectively. The quantities of derivatives of xylitol and lactitol obtained through the application of enzymes from K. lactis and K. fragilis were comparable – up to 14.7 % [w/w] of gal‐xylitol and up to 17.2 % [w/w] of gal‐lactitol. Enzymes from yeasts showed a larger affinity towards the synthesis of derivatives of polyol‐monomers, whereas the enzyme from mould synthesized trimers faster. An excessive addition of enzymes brought about an intensification of gal‐polyol hydrolysis and a decrease of their content in the hydrolysates. Thus, the amount of β‐galactosidase to be added should not exceed 2500 AUL/100 mL in gal‐erythritol synthesis, 1300 AUL/100 mL in gal‐xylitol synthesis, 4000 AUL/100 mL in gal‐sorbitol synthesis a well as 2600 AUL/100 mL in gal‐lactitol synthesis.
The Light Quanta Modulated Physiological Response of Brassica Juncea Seedlings Subjected to Ni(II) Stress
Authors: Dasgupta‐Schubert N. , Alexander S. , Sommer L. , Whelan T. , Alfaro Cuevas Villanueva R. , Mendez Lopez M. E. , Persans M. W.
Published: May 2007

This work is a study of the inter‐relationship between parameters that principally affect the metal up‐take in the plant. The relationships between the concentration of metal in the growth medium, Cs, the concentration of metal absorbed by the plant, Cp, and the total biomass achieved, M, all of which are factors relevant to the efficiency of phytoremediation of the plant, have been investigated via the macro‐physiological response of Brassica juncea seedlings to Ni(II) stress. The factorial growth experiments treated the Ni(II) concentration in the agar gel and the diurnal light quanta (DLQ) as independently variable parameters. Observations included the evidence of light enhancement of Ni toxicity at the root as well as at the whole plant level, the shoot mass index as a possible indicator of shoot metal sequestration in B. juncea, the logarithmic variation of Cp with Cs and the power‐law dependence of M on Cp. The sum total of these observations indicates that for the metal accumulator B. juncea with regard to its capacity to accumulate Ni, the overall metabolic nature of the plant is important – neither rapid biomass increase nor a high metal concentration capability favor the removal of high metal mass from the medium, but rather the plant with the moderate photosynthetically driven biomass growth and moderate metal concentrations demonstrated the ability to remove the maximum mass of metal from the medium. The implications of these observations in the context of the perceived need in phytoremediation engineering to maximize Cp and M simultaneously in the same plant, are discussed.
Growth of Chlorinated Solvent‐Degrading Consortia in Fed‐Batch Bioreactors and Development of a Double‐Substrate High‐Performing Microbial Inoculum
Authors: Gualandi G. , Frascari D. , Pinelli D. , Nocentini M.
Published: May 2007

The long‐term growth process of two microbial consortia effective in the aerobic cometabolic biodegradation of a mixture of 6‐chlorinated aliphatic hydrocarbons (CAHs), the effectiveness of these consortia as inocula for the bio‐augmentation of different types of microcosms and the development of a double‐substrate, high‐performing consortium is presented. The propane‐utilizing consortium generally proved to be the most effective one, being able to biodegrade vinyl chloride, cis‐ and trans‐1,2‐dichloroethylene, trichloroethylene, 1,1,2‐trichloroethane and 1,1,2,2‐tetrachloroethane at all the CAH concentrations tested (0–4 μM). Both consortia maintained unaltered CAH degradation capacities over a 300‐day growth period in the absence of the CAHs and were effective in inducing the rapid onset of CAH depletion upon inoculation in slurry microcosms set up with five types of aquifer materials. A consortium supplied with both methane and propane combined the best degradation capacities of the two single‐substrate consortia, and maintained stable performances for 150 days under slurry conditions. The degree of conversion of the organic Cl to chloride ions was equal to 90 %.
Bioactive Sulforaphane from in vitro Propagated Brassica Seedlings
Authors: Sivakumar G. , Aliboni A. , Antonini A. , Bacchetta L.
Published: May 2007

Sulforaphane is a biologically active phytochemical found abundantly in Brassica species. Sulforaphane from eighteen samples of three‐day‐old in vitro seedlings from Brassicas, the Brassica oleracea and Brassica rapa varieties were analyzed by HPLC. San Martino, cavolfiore Alverda, cavolo verza riccio d'Asti and cavolfiore Minaret (4.57; 4.54; 4.53 and 4.53 [mg/g d.w], respectively) seedlings showed the highest level of sulforaphane. The presented data may be applicable to choose sulforaphane‐rich Brassica varieties for functional foods. A higher sulforaphane content in functional foods might offer health benefits or desirable physiological effects.
Order imbalance and the pricing of index futures
Authors: Fung Joseph K.W.
Published: May 2007

This study examines whether the aggregate order imbalance for index stocks can explain the arbitrage spread between index futures and the underlying cash index. The study covers the period of the Asian financial crisis and includes wide variations in order imbalance and the indexfutures basis. The analysis controls for realistic trading costs and actual dividend payments. The results indicate that the arbitrage spread is positively related to the aggregate order imbalance in the underlying index stocks; negative order‐imbalance has a stronger impact than positive order imbalance. Violations of the upper no‐arbitrage bound are related to positive order imbalance; of the lower no‐arbitrage bound to negative order imbalance. Asymmetric response times to negative and positive spreads can be attributed to the difficulty, cost, and risk of short stock arbitrage when the futures are below their no‐arbitrage value. The significant relationship between order imbalance and arbitrage spread confirms that index arbitrageurs are important providers of liquidity in the futures market when the stock market is in disequilibrium. © 2007 Wiley Periodicals, Inc. Jrl Fut Mark 27:697–717, 2007
Role of phospholipase D2 in anti‐apoptotic signaling through increased expressions of Bcl‐2 and Bcl‐xL
Authors: Oh Kyoung‐Jin , Lee Sung‐Chang , Choi Hye‐Jin , Oh Doo‐Yi , Kim Sang‐Chul , Min Do Sik , Kim Jung Mogg , Lee Ki Sung , Han Joong‐Soo
Published: May 2007

We have previously reported that Fas‐resistant A20 cells (FasR) have phospholipase D (PLD) activity upregulated by endogenous PLD2 overexpression. In the present study, we investigated how overexpressed PLD2 in FasR could generate survival signals by regulating the protein levels of anti‐apoptotic Bcl‐2 and Bcl‐xL. To confirm the effect of PLD2 on Bcl‐2 protein levels, we transfected PLD2 into wild‐type murine B lymphoma A20 cells. The transfected cells showed markedly the increases in Bcl‐2 and Bcl‐xL protein levels, and became resistant to Fas‐induced apoptosis, similar to FasR. Treatment of wild‐type A20 cells with phosphatidic acid (PA), the metabolic end product of PLD2 derived from phosphatidylcholin, markedly increased levels of anti‐apoptotic Bcl‐2 and Bcl‐xL proteins. Moreover, PA‐induced expressions of Bcl‐2 and Bcl‐xL were enhanced by propranolol, an inhibitor of PA phospholydrolase (PAP), whereas completely blocked by mepacrine, an inhibitor of phospholipase A2 (PLA2), suggesting that PLA2 metabolite of PA is responsible for the increases in Bcl‐2 and Bcl‐xL protein levels. We further confirmed the involvement of arachidonic acid (AA) in PA‐induced survival signals by showing that 1,2‐dipalmitoyl‐sn‐glycero‐3‐phosphate (DPPA), PA without AA, was unable to increase Bcl‐2 and Bcl‐xL proteins. Moreover, PA notably increased cyclooxygenase (COX)‐2 protein expression, and PA‐induced expression of both Bcl‐2 and Bcl‐xL was inhibited by NS‐398, a specific inhibitor of COX‐2. Taken together, these findings demonstrate that PA generated by PLD2 plays an important role in cell survival during Fas‐mediated apoptosis through the increased Bcl‐2 and Bcl‐xL protein levels which resulted from PLA2 and AA‐COX2 pathway. J. Cell. Biochem. 101: 1409–1422, 2007. © 2007 Wiley‐Liss, Inc.
The proteasome regulates the interaction between Cx43 and ZO‐1
Authors: Girao Henrique , Pereira Paulo
Published: May 2007

Gap junction (GJ) intercellular communication (GJIC) is vital to ensure proper cell and tissue function. GJ are multimeric structures composed of proteins called connexins. Modifications on stability or subcellular distribution of connexins have a direct impact on the extent of GJIC. In this study we have investigated the role of the proteasome in regulation of connexin 43 (Cx43) internalization. Although the participation of both the proteasome and lysosome has long been suggested in Cx43 degradation, the molecular mechanisms whereby proteasome contributes to regulate Cx43 internalization and intercellular communication are still unclear. The results presented in this study envision a new mechanism whereby proteasome regulates GJIC by modulating interaction between Cx43 and ZO‐1. Immunoprecipitation experiments, in the presence of proteasome inhibitors, together with immunofluorescence data indicate that the proteasome regulates interaction between Cx43 and ZO‐1. Overexpression of the PDZ2 domain of ZO‐1 and the expression of Cx‐43 fused in frame with a V5/HIS tag, suggest that interaction between the two proteins occurs through the PDZ2 domain of ZO‐1 and the C‐terminus of Cx43. When interaction between Cx43 and ZO‐1 is reduced, as in the presence of proteasome inhibitors, Cx43 accumulates, forming large GJ plaques at plasma membrane. Data presented in this article suggest a new pathway whereby alterations in proteasome activity may impact on GJIC as well as on non‐junctional communication with extracellular environment, contributing to cell and tissue dysfunction. J. Cell. Biochem. 102: 719–728, 2007. © 2007 Wiley‐Liss, Inc.
Co‐inoculation of prostate cancer cells with U937 enhances tumor growth and angiogenesis in vivo
Authors: Craig Matthew , Ying Chi , Loberg Robert D.
Published: May 2007

Tumor‐associated macrophages (TAMs) have been implicated in promoting tumor growth and development. Here we present evidence that demonstrates that co‐inoculation of male athymic nude mice with PC‐3 prostate cancer cells and U937 promonocytic cells enhances tumor growth and increases tumor angiogenesis.
Male athymic nude mice were co‐inoculated with PC‐3 and U937 cells (control or IL‐4 stimulated) and tumor growth was monitored over time. Immunohistochemical analysis of tumor specimens was performed for proliferation markers (e.g., Ki67) and the effects of IL‐4 stimulation on U937 cells were analyzed for chemokine expression.
The presence of U937 cells increased the rate of tumor growth in vivo and stimulated increased microvascular density within the tumor bed. Stimulation of U937 cells with IL‐4 resulted in a significant increase in several pro‐angiogenic and pro‐tumor chemokines (e.g., CCL2).
Co‐inoculation increases prostate cancer growth via upregulation of chemokines that induce angiogenesis within the tumor. J. Cell. Biochem. 103: 1–8, 2008. © 2007 Wiley‐Liss, Inc.
Intranuclear mobility of estrogen receptor α and progesterone receptors in association with nuclear matrix dynamics
Authors: Matsuda KenIchi , Nishi Mayumi , Takaya Hisamitsu , Kaku Natsuko , Kawata Mitsuhiro
Published: May 2007

We analyzed the intranuclear dynamics of estrogen receptor α (ERα) and progesterone receptor (PR)‐A/B labeled with different spectral variants of green fluorescent protein (GFP) in living cells. The distribution of ERα and PR‐A/B were changed from a diffuse to discrete pattern after the addition of both ligands, but the extent of discrete cluster formation of PR‐A/B was lower than that of ERα. The nuclear areas where PR‐A/B were accumulated were colocalized with the cluster of ERα, suggesting that cross‐talk in the transcriptional regulation occurred in the loci. Fluorescence recovery after photobleaching (FRAP) analysis revealed that the mobility of PR‐A/B was hastened by the coexistence of ERα, while the mobility of ERα was not changed by the coexistence of PR‐A/B. Cluster formation was correlated with the nuclear matrix binding, because nuclear matrix binding capacity was also lower in PR‐A/B than ERα. By ATP‐depletion from the cells, most of ERα and PR‐A/B were bound to the nuclear matrix and their mobilities were extinguished both in the absence and presence of ligand. Fluorescent protein (FP) tagged nuclear matrix component protein (NuMA), which was colocalized with ERα and PR‐A/B, showed ATP‐dependent rapid exchange in the nucleus. These results indicate that the mobility of ERα and PR‐A/B is associated with the dynamics of the nuclear matrix. J. Cell. Biochem. 103: 136–148, 2008. © 2007 Wiley‐Liss, Inc.
Matrigel‐induced acinar differentiation is followed by apoptosis in HSG cells
Authors: Szlávik Vanda , Vág János , Markó Károly , Demeter Kornél , Madarász Emília , Oláh Imre , Zelles Tivadar , O'Connell Brian C. , Varga Gábor
Published: May 2007

It has been shown that a human salivary gland cell line (HSG) is capable of differentiation into gland‐like structures, though little is known of how morphological features are formed or controlled. Here we investigated the changes in cell proliferation and apoptosis upon terminal differentiation of HSG cells in Matrigel, an extracellular matrix derivative. Changes in the expression of survivin, a prominent anti‐apoptotic factor, and caspase‐3, a key apoptotic factor were also measured. In order to better understand the involvement of key signal transduction pathways in this system we pharmacologically blocked the activity of tyrosine kinase, nuclear factor kappa B(NFκB), protein kinase C (PKC), phosphatidylinositol 3‐kinase (PI3K) and matrix metalloproteases (MMP). Results of these studies demonstrate that cytodifferentiation of HSG cells to an acinar phenotype is accompanied first by a decrease of cell proliferation and then by a massive programmed cell death, affected by multiple signal transduction pathways. Thus, Matrigel alone is insufficient for the full maturation and long term survival of the newly formed acini: the presence of other factors is necessary to complete the acinar differentiation of HSG cells. J. Cell. Biochem. 103: 284–295, 2008. © 2007 Wiley‐Liss, Inc.
Yeast Nα‐terminal acetyltransferases are associated with ribosomes
Authors: Polevoda Bogdan , Brown Steven , Cardillo Thomas S. , Rigby Sean , Sherman Fred
Published: May 2007

N‐terminal acetylation is one of the most common modifications, occurring on the vast majority of eukaryotic proteins. Saccharomyces cerevisiae contains three major NATs, designated NatA, NatB, and NatC, with each having catalytic subunits Ard1p, Nat3p, and Mak3p, respectively. Gautschi et al. (Gautschi et al. [2003] Mol Cell Biol 23: 7403) previously demonstrated with peptide crosslinking experiments that NatA is bound to ribosomes. In our studies, biochemical fractionation in linear sucrose density gradients revealed that all of the NATs are associated with mono‐ and polyribosome fractions. However only a minor portion of Nat3p colocalized with the polyribosomes. Disruption of the polyribosomes did not cause dissociation of the NATs from ribosomal subparticles. The NAT auxiliary subunits, Nat1p and Mdm20p, apparently are required for efficient binding of the corresponding catalytic subunits to the ribosomes. Deletions of the genes corresponding to auxiliary subunits significantly diminish the protein levels of the catalytic subunits, especially Nat3p, while deletions of the catalytic subunits produced less effect on the stability of Nat1p and Mdm20p. Also two ribosomal proteins, Rpl25p and Rpl35p, were identified in a TAP‐affinity purified NatA sample. Moreover, Ard1p copurifies with Rpl35p‐TAP. We suggest that these two ribosomal proteins, which are in close proximity to the ribosomal exit tunnel, may play a role in NatA attachment to the ribosome. J. Cell. Biochem. 103: 492–508, 2008. © 2007 Wiley‐Liss, Inc.
The role of androgen in determining differentiation and regulation of androgen receptor expression in the human prostatic epithelium transient amplifying population
Authors: Heer R. , Robson C.N. , Shenton B.K. , Leung H.Y.
Published: May 2007

Abnormal differentiation in epithelial stem cells or their immediate proliferative progeny, the transiently amplifying population (TAP), may explain malignant pathogenesis in the human prostate. These models are of particular importance as differing sensitivities to androgen among epithelial cell subpopulations during differentiation are recognised and may account for progression to androgen independent prostate cancer. Androgens are crucial in driving terminal differentiation and their indirect effects via growth factors from adjacent androgen responsive stroma are becoming better characterised. However, direct effects of androgen on immature cells in the context of a prostate stem cell model have not been investigated in detail and are studied in this work. In α2β1hi stem cell enriched basal cells, androgen analogue R1881 directly promoted differentiation by the induction of differentiation‐specific markers CK18, androgen receptor (AR), PSA and PAP. Furthermore, treatment with androgen down‐regulated α2β1 integrin expression, which is implicated in the maintenance of the immature basal cell phenotype. The α2β1hi cells were previously demonstrated to lack AR expression and the direct effects of androgen were confirmed by inhibition using the anti‐androgen bicalutamide. AR protein expression in α2β1hi cells became detectable when its degradation was repressed by the proteosomal inhibitor MG132. Stratifying the α2β1hi cells into stem (CD133+) and transient amplifying population (TAP) (CD133−) subpopulations, AR mRNA expression was found to be restricted to the CD133− (TAP) cells. The presence of a functional AR in the TAP, an androgen independent subpopulation for survival, may have particular clinical significance in hormone resistant prostate cancer, where both the selection of immature cells and functioning AR regulated pathways are involved. J. Cell. Physiol. 212:572–578, 2007. © 2007 Wiley‐Liss, Inc.
LRRC4 inhibits glioblastoma cell proliferation, migration, and angiogenesis by downregulating pleiotropic cytokine expression and responses
Authors: Wu Minghua , Huang Chen , Li Xiayu , Li Xiaoling , Gan Kai , Chen Qiong , Tang Yunlian , Tang Ke , Shen Shourong , Li Guiyuan
Published: May 2007

Leucine‐rich repeat C4 (LRRC4) has been shown to inhibit glioma cell proliferation, however, little is known about the mechanism(s) underlying the action of LRRC4. Here, we show that two glioblstoma U251 cell clones stably expressing LRRC4 were established. LRRC4 expression significantly inhibited the expression of some cytokines and their receptors determined by microarray and Western blot assays, and dramatically reduced cytokine‐induced AP‐1, NF‐kB, and CyclinD1 activation in glioma cells. Furthermore, LRRC4 expression in glioma cells significantly downregulated spontaneous and cytokine‐induced expression of K‐RAS and phosphorylation of c‐Raf, ERK, AKT, NF‐kBp65, p70S6K, and PKC, suggesting that LRRC4 inhibited receptor tyrosine kinase (RTK) signaling pathways. Moreover, treatment with bFGF, IGF1, or IGF2 stimulated LRRC4−/−, but not the LRRC4+, glioma cell proliferation, indicating that LRRC4 mitigated cytokine‐stimulated proliferation in glioma cells. In addition, treatment of LRRC4−/− glioma cells with EGF, IGF2, or PDGF promoted long distance mobilization, but induced little migration in LRRC4+ glioma cells, suggesting that LRRC4 retarded cytokine‐promoted glioma cell migration in vitro. Finally, human vessel endothelial cells (ECV304) treated with VEGF grew, aligned and formed hollow tube‐like structures in vitro. In contrast, LRRC4+ ECV304 treated with VEGF failed to form vessel‐tube structures. Collectively, LRRC4 expression inhibited the expression of some growth factors, cytokines and their receptors, and the capacity of glioma cells responding to cytokine stimulation, leading to inhibition of glioma cell proliferation. Conceivably, induction of LRRC4 expression may provide new intervention for human glioma in the clinic. J. Cell. Physiol. 214:65–74, 2008. © 2007 Wiley‐Liss, Inc.
Integration of wings and their eyespots in the speckled wood butterflyPararge aegeria
Authors: Breuker Casper J. , Gibbs Melanie , Van Dyck Hans , Brakefield Paul M. , Klingenberg Christian Peter , Van Dongen Stefan
Published: May 2007

We investigated both the phenotypic and developmental integration of eyespots on the fore‐ and hindwings of speckled wood butterfliesPararge aegeria. Eyespots develop within a framework of wing veins, which may not only separate eyespots developmentally, but may at the same time also integrate them by virtue of being both signalling sources and barriers during eyespot development. We therefore specifically investigated the interaction between wing venation patterns and eyespot integration. Phenotypic covariation among eyespots was very high, but only eyespots in neighbouring wing cells and in homologous wing cells on different wing surfaces were developmentally integrated. This can be explained by the fact that the wing cells of these eyespots share one or more wing veins. The wing venation patterns of fore‐ and hindwings were highly integrated, both phenotypically and developmentally. This did not affect overall developmental integration of the eyespots. The adaptive significance of integration patterns is discussed and more specifically we stress the need to conduct studies on phenotypic plasticity of integration.J. Exp. Zool. (Mol. Dev. Evol.) 308B:454–463, 2007. © 2007 Wiley‐Liss, Inc.
Improving fragmentation of poorly fragmenting peptides and phosphopeptides during collision‐induced dissociation by malondialdehyde modification of arginine residues
Authors: Leitner Alexander , Foettinger Alexandra , Lindner Wolfgang
Published: May 2007

Despite significant technological and methodological advancements in peptide sequencing by mass spectrometry, analyzing peptides that exhibit only poor fragmentation upon collision‐induced dissociation (CID) remains a challenge. A major cause for unfavorable fragmentation is insufficient proton ‘mobility’ due to charge localization at strongly basic sites, in particular, the guanidine group of arginine. We have recently demonstrated that the conversion of the guanidine group of the arginine side chain by malondialdehyde (MDA) is a convenient tool to reduce the basicity of arginine residues and can have beneficial effects for peptide fragmentation. In the present work, we have focused on peptides that typically yield incomplete sequence information in CID‐MS/MS experiments. Energy‐resolved tandem MS experiments were carried out on angiotensins and arginine‐containing phosphopeptides to study in detail the influence of the modification step on the fragmentation process. MDA modification dramatically improved the fragmentation behavior of peptides that exhibited only one or two dominant cleavages in their unmodified form. Neutral loss of phosphoric acid from phosphopeptides carrying phosphoserine and threonine residues was significantly reduced in favor of a higher abundance of fragment ions. Complementary experiments were carried out on three different instrumental platforms (triple‐quadrupole, 3D ion trap, quadrupole–linear ion trap hybrid) to ascertain that the observation is a general effect. Copyright © 2007 John Wiley & Sons, Ltd.
Metastatic bone disease: A 36‐Year single centre trend‐analysis of patients admitted to a tertiary orthopaedic surgical department
Authors: Toma C.D. , Dominkus M. , Nedelcu T. , Abdolvahab F. , Assadian O. , Krepler P. , Kotz R.
Published: May 2007

Background and Objectives

The treatment and outcome of primary malignant bone tumours has changed with the advances in diagnostic and treatment modalities. A trend‐analysis on a large cohort of patients with metastatic bone disease was performed.

Methods

A retrospective chart review of all cases with metastatic bone disease admitted to a single tertiary orthopaedic referral centre, registered with the Vienna Bone and Soft Tissue Tumour Registry between 1968 and 2003 was conducted. For trend‐analysis of frequency, survival, primary site, treatment methods, and others, the 36‐year study duration was divided into four periods.

Results

The study identified 601 females and 580 males (mean: 60 years) with metastatic bone disease. The most common metastases were secondary to breast cancer (n = 275; 23%) and renal cell carcinoma (n = 242; 21%) and the majority were located in the femur (n = 332; 28%) and spine (n = 348; 29%). Overall, the proportion of patients who underwent surgery decreased. At follow‐up, 887 (75%) patients were verified to have died of their disease.

Conclusions

Over the 36‐year period, the frequency of bone metastases has increased at our centre. Although survival increased over time, the difference was not significant; this was most likely attributable to the seriousness of cases referred to our tertiary care centre. J. Surg. Oncol. 2007;96:404–410. © 2007 Wiley‐Liss, Inc.
Rapid determination of C12–C26 non‐derivatized fatty acids in human serum by fast gas chromatography
Authors: Meng Zhe , Wen Dawei , Sun Dandan , Gao Fei , Li Wei , Liao Yiping , Liu Huwei
Published: May 2007

The concentration of long‐chain fatty acids (LCFAs) in human serum is closely related to human health. It is therefore important to develop a fast, low‐cost, efficient method for their determination. In this study, by using fast temperature programming and micro‐bore short capillary columns, a fast gas chromatography method was developed for the direct analysis of non‐derivatized LCFAs including n‐dodecanoic acid to n‐hexacosanic acid (C12:0–C26:0, even numbers only), linoleic acid (C18:2), oleic acid (C18:1), and erucic acid (C22:1) within 4.0 min. Method optimization including extraction and separation conditions is considered, and the analysis of real serum samples is presented. The results show that ten LCFAs were well separated with sufficient resolution, and the detection limit was in the range of 2.8–9.6 μg/mL. The reproducibility (RSD) for both intra‐day and inter‐day determination was always less than 15%, and the recoveries for these LCFAs were from 63.1 to 97.0%.
Stationary phase characterization and method development
Authors: Neue Uwe D.
Published: May 2007

The properties of stationary phases and their characterization methods are reviewed. New and significant developments have occurred in the last few years, and new methods for stationary phase characterization have become available. The characterization methods are discussed, and the differences between the different methods are pointed out. In addition, method development approaches are reviewed, with special emphasis on recent developments that employ multiple parameters in parallel. Also, the renewed interest of temperature as a tool in method development is surveyed.
Reversible photo-darkening and resonant photo-bleaching of Ytterbium-doped silica fiber at in-core 977-nm and 543-nm irradiation
Authors: Guzman Chávez A D , Kir'yanov A V , Barmenkov Y O , Il'ichev N N
Published: May 2007

We report experimental results showing novel features in photo-darkening and photo-bleaching of a heavily-doped Ytterbium silica fiber exposed to in-core 977-nm and 543-nm irradiation. It is shown that pumping of the fiber at the resonant 977-nm wavelength leads to an increase of absorption in the spectrally wide range (400–1000 nm, photo-darkening) and a simultaneous decrease of the resonant (Yb3+) absorption coefficient near ∼ 1 μm (resonant photo-bleaching). Such a character of the Ytterbium fiber spectra transformations allows us to propose that they are a signature of the 977-nm light-induced Yb3+ → Yb2+ conversion process, with the spectrally wide absorption, or photo-darkening, to arise owing to the Yb2+ centers formation and the resonant photo-bleaching to stem from the corresponding decrease of Yb3+ ions concentration. It is as well demonstrated that an exposure of the Ytterbium fiber, where the aforementioned transformations have occurred, to the 543-nm light results in a partial return of the initial fiber properties – bleaching of the spectrally wide excess loss in the visible and increasing of the resonant 977-nm (Yb3+) absorption peak. Therefore, we reveal a reverse process, Yb2+ → Yb3+, possibly taking place in the last case.