bluuebunny/crossref_metadata_2025 huggingface dataset:
Palladium‐Catalyzed Insertion of α‐Diazoesters into Vinyl Halides To Generate α,β‐Unsaturated γ‐Amino Esters
Authors: Kudirka Romas , Devine Sean K. J. , Adams Christopher S. , Van Vranken David L.
Published: April 2009

So einfach wie auf drei zu zählen: Eine Palladium‐katalysierte Dreikomponentenkupplung erzeugt in einem Schritt α,β‐ungesättigte γ‐Aminosäuren (siehe Schema). Die Reaktion umfasst vermutlich die Wanderung eines Vinylsubstituenten zu einem hoch elektrophilen Palladiumcarben. Anders als herkömmliche Verfahren bietet diese Synthese Zugang zu γ‐Aminosäuren mit nichtnatürlichen Seitenketten.

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Dual‐Function Probe to Detect Protease Activity for Fluorescence Measurement and 19F MRI
Authors: Mizukami Shin , Takikawa Rika , Sugihara Fuminori , Shirakawa Masahiro , Kikuchi Kazuya
Published: April 2009

Dynamisches Duo: Die Kernspintomographie (MRI) kann tiefliegendes Gewebe in vivo visualisieren, während Fluoreszenzmessungen ausgezeichnete Empfindlichkeiten bieten. Die kombinierte Verwendung beider Methoden ermöglicht Signalverstärkungen, die zur Detektion von Enzymaktivitäten ausreichen. Eine Zweikanalsonde zur Detektion der Caspase‐3‐Aktivität durch Fluoreszenzspektroskopie und 19F‐MRI wird vorgestellt.

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Formal Total Synthesis of Platencin
Authors: Varseev Georgy N. , Maier Martin E.
Published: April 2009

Der richtige Bicyclus: Die effiziente sauerstoffvermittelte palladiumkatalysierte Cycloalkenylierung von 1 zu einem Bicyclo[3.2.1]octan und die desoxygenierende Umlagerung des Tosylhydrazons 2 zum Bicyclo[2.2.2]octan 3 sind wesentliche Schritte der Synthese der Kernstruktur 4 von Platencin, deren Gesamtausbeute nach 13 Stufen ausgehend von einer käuflich erhältlichen Verbindung 17.5 % betrug. Ts=p‐Toluolsulfonyl, TBS=tert‐Butyldimethylsilyl, Piv=Pivaloyl.

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Licht am Ende des Tunnels
Authors: Heilemann Mike
Published: April 2009

Die Kinetik der Synthese, Faltung und Reifung einzelner Moleküle des grün fluoreszierenden Proteins (GFP) wurde an einem Translations‐Transkriptions‐System in vitro mithilfe von Einzelmolekülmikroskopie untersucht. Dazu wurden einzelne, mit einem roten Fluoreszenzfarbstoff markierte Ribosomen auf einer Oberfläche angebracht. Vollständig gereifte GFP‐Emerald‐Moleküle wurden anhand ihrer grünen Fluoreszenz erkannt.

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1,4‐Bis(alkenyl)‐2,5‐dipiperidinobenzenes: Minimal Fluorophores Exhibiting Highly Efficient Emission in the Solid State
Authors: Shimizu Masaki , Takeda Youhei , Higashi Masahiro , Hiyama Tamejiro
Published: April 2009

Minimale Anforderung: Kristalle und dünne Filme von 1,4‐Bis(alkenyl)‐2,5‐dipiperidinobenzolen, die lediglich einen Benzolring als aromatische Komponente enthalten, emittieren sichtbares Licht mit hervorragenden Quantenausbeuten, wenn sie mit UV‐Licht bestrahlt werden. Mit diesen Verbindungen dotierte dünne Polystyrolfilme fluoreszieren ebenfalls kräftig. Durch Variation der Alkenylgruppen werden Farben im Bereich zwischen Blau und Rot erzielt.

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Chiral Recognition of Hybrid Metal Oxide by Peptides
Authors: Micoine Kévin , Hasenknopf Bernold , Thorimbert Serge , Lacôte Emmanuel , Malacria Max
Published: April 2009

Resolution of gram quantities of a subtly chiral polyoxometalate (POM; the chirality originates from substitution of one metal in the nanosized framework) is possible by reaction with small peptides. Functionalizable acyl polyoxotungstate (TBA)6[α1‐P2W17O61{SnCH2CH2C(O)}] (see picture) can be resolved by kinetic resolution. This approach paves the way for applications of chiral POMs ranging from asymmetric catalysis to their bioactivity.

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A Spherical Molecule with a Carbon‐Free Ih‐C80 Topological Framework
Authors: Scheer Manfred , Schindler Andrea , Gröger Christian , Virovets Alexander V. , Peresypkina Eugenia V.
Published: April 2009

The complete encapsulation of ortho‐carborane by a fullerene‐like building‐block system consisting of pentaphosphaferrocene and CuICl leads to the formation of the spherical supermolecule C2B10H12§[{Cp*Fe(η5‐P5)}12(CuCl)20]. This product of template‐controlled aggregation represents the first example of a carbon‐free C80 analogue possessing icosahedral symmetry.

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Light at the End of the Tunnel
Authors: Heilemann Mike
Published: April 2009

Turn the light on: The synthesis, folding and maturation kinetics of individual green fluorescent protein (GFP) molecules have been studied using a cell‐free transcription–translation system and single‐molecule fluorescence. Ribosomes, which were labeled with a red fluorophore and tethered to a glass surface, were used to synthesize GFP Emerald molecules that become fluorescent after maturation.

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Olive‐Shaped Chiral Supramolecules: Simultaneous Self‐Assembly of Heptameric Lanthanum Clusters and Carbon Dioxide Fixation
Authors: Tang Xiao‐Liang , Wang Wen‐Hua , Dou Wei , Jiang Jie , Liu Wei‐Sheng , Qin Wen‐Wu , Zhang Guo‐Lin , Zhang Hong‐Rui , Yu Kai‐Bei , Zheng Li‐Min
Published: April 2009

Cluster's last stand: Six chiral reduced Schiff base ligands containing amino acids and seven LaIII ions self‐assemble to form a novel heptameric lanthanum supramolecule with the aid of the CO32− ion (see picture). The cluster exists as a single chiral triple helix. The CO32− ion, which is derived from atmospheric CO2 , adopts a rare μ3‐tridentate bridging mode that links three LaIII ions, thus allowing the cluster to efficiently fix CO2.

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1,4‐Bis(alkenyl)‐2,5‐dipiperidinobenzenes: Minimal Fluorophores Exhibiting Highly Efficient Emission in the Solid State
Authors: Shimizu Masaki , Takeda Youhei , Higashi Masahiro , Hiyama Tamejiro
Published: April 2009

Minimum requirements: Crystals and thin films of 1,4‐bis(alkenyl)‐2,5‐dipiperidinobenzenes, which contain only one benzene ring as the aromatic component, emit visible light with excellent solid‐state quantum yields upon irradiation with UV light. Polystyrene thin films doped with the benzenes also exhibit brilliant fluorescence. By modifying the alkenyl groups, the emission color can be tuned in the range from blue to red.

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Inside Cover: Synthesis and Biological Activity of Argiotoxin 636 and Analogues: Selective Antagonists for Ionotropic Glutamate Receptors (Angew. Chem. Int. Ed. 17/2009)
Authors: Nelson Jared K. , Frølund Sidsel U. , Tikhonov Dennis B. , Kristensen Anders S. , Strømgaard Kristian
Published: April 2009

Spiders of the genus Argiope, such as Argiope lobata, contain polyamine toxins that are potent but nonselective blockers of glutamate receptors. However, by very subtle modifications of the structure of native toxins, it is possible to obtain selectivity for subtypes of these receptors, as described by K. Strømgaard and co‐workers in their Communication on page 3087 ff.

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Hormonal and nutritional regulation of insect fat body development and function
Authors: Liu Ying , Liu Hanhan , Liu Shumin , Wang Sheng , Jiang Rong‐Jing , Li Sheng
Published: April 2009

The insect fat body is an organ analogue to vertebrate adipose tissue and liver and functions as a major organ for nutrient storage and energy metabolism. Similar to other larval organs, fat body undergoes a developmental “remodeling” process during the period of insect metamorphosis, with the massive destruction of obsolete larval tissues by programmed cell death and the simultaneous growth and differentiation of adult tissues from small clusters of progenitor cells. Genetic ablation of Drosophila fat body cells during larval‐pupal transition results in lethality at the late pupal stage and changes sizes of other larval organs indicating that fat body is the center for pupal development and adult formation. Fat body development and function are largely regulated by several hormonal (i.e. insulin and ecdysteroids) and nutritional signals, including oncogenes and tumor suppressors in these pathways. Combining silkworm physiology with fruitfly genetics might provide a valuable system to understand the mystery of hormonal regulation of insect fat body development and function. © 2009 Wiley Periodicals, Inc.
Embryo/fetal development in cynomolgus monkeys exposed to natalizumab, an α4 integrin inhibitor
Authors: Wehner Nancy G. , Shopp George , Oneda Satoru , Clarke Janet
Published: April 2009

BACKGROUND: Natalizumab is a humanized monoclonal immunoglobulin G4 antibody to human α4 integrin that binds to the α4 subunit of α4β1 and α4β7 integrins, where it blocks the interaction of these integrins with their ligands, including fibronectin, vascular cell adhesion molecule‐1, and mucosal addressin cellular adhesion molecule‐1. Because α4 integrins and their ligands appear to be involved in mammalian fetal development, it is possible that natalizumab may interfere with these processes. METHODS: The effects of natalizumab on fetal development were assessed in cynomolgus monkeys at doses of 0, 3, 10, and 30 mg/kg administered intravenously every other day from gestational day (GD) 20 to 70. Pregnancies were terminated by Cesarean section at GD 100. RESULTS: Natalizumab treatment was not associated with increased abortions. All fetuses were alive. No external, visceral, or skeletal abnormalities were seen that were considered to be related to treatment with natalizumab. No histopathological findings were seen in the heart, a target organ of developmental toxicity with a small molecule inhibitor of α4 integrin. At dose levels ≥10 mg/kg, hematological and/or lymphoid effects were observed in some fetuses, consisting of slight thymic atropy, increased extramedullary hematopoiesis in the spleen with a corresponding decrease in the liver, increases in WBC and nucleated RBC, decreases in RBC parameters, and decreases in lymphoid CD20 staining. CONCLUSION: Natalizumab had no abortifacient or teratogenic effects, but was associated with changes in fetal hematopoiesis and leukocyte trafficking. Birth Defects Res (Part B)86: 117‐130, 2009. © 2009 Wiley‐Liss, Inc.
Cytoprotective effect of Artemisia capillaris fractions on oxidative stress‐induced apoptosis in V79 cells
Authors: Hong Jung‐Hee , Lee In‐Seon
Published: April 2009

The objectives of this study were to determine the effects of Artemisia capillaris on the viability, antioxidant status, and cytoprotective against oxidative stress induced by hydrogen peroxide in V79 cells. Pretreatment with ethyl acetate fraction increased 363% cell viability compared to the positive control (PC). The ethyl acetate fraction of A. capillaris scavenged intracellular reactive oxygen species (ROS) and increased the activities of cellular antioxidant enzymes like superoxide dismutase (SOD), glutathione peroxidase (GSH‐px), and catalase (CAT), and also increased glutathione (GSH) content. It thereby prevented lipid peroxidation which was demonstrated by the inhibition of the formation of thiobarbituric acid reactive substance (TBARS). Furthermore, ethyl acetate fraction reduced the apoptotic cells and cell cycle arrest at G2/M phase induced by H2O2. These findings suggest that A. capillaris ethyl acetate fraction protected V79 cells against H2O2 damage, by enhancing the antioxidative activity. © 2009 International Union of Biochemistry and Molecular Biology, Inc.
Luteolin inhibits adipogenic differentiation by regulating PPARγ activation
Authors: Park Hee‐Sook , Kim Soon‐Hee , Kim Young Sup , Ryu Shi Yong , Hwang Jin‐Taek , Yang Hye Jeong , Kim Gun‐Hee , Kwon Dae Young , Kim Myung‐Sunny
Published: April 2009

Luteolin (3′,4′,5,7‐tetrahydroxyflavone), a flavonoid, has been known to possess antimutagenic, antitumorigenic, antioxidant, and anti‐inflammatory properties. In this study, we investigated the role of luteolin in the regulation of adipogenic differentiation in 3T3‐L1 preadipocytes. Luteolin inhibited intracellular triglyceride accumulation in a dose‐dependent manner without cytotoxicity. Western blot and reverse transcription‐polymerase chain reaction analyses showed that this inhibition was accompanied by attenuated expression of the adipogenic transcription factors: peroxisome proliferator‐activated receptor γ (PPARγ) and CCAAT/enhancer‐binding protein α. Luteolin inhibited the PPARγ transactivation stimulated by rosiglitazone, a synthetic agonist, in COS‐7 cells and inhibited rosiglitazone‐induced adipogenic differentiation in 3T3‐L1 cells. These data suggest that luteolin exerts antiadipogenic effects by suppressing adipogenic transcription factors and by inhibiting the transactivation of PPARγ. © 2009 International Union of Biochemistry and Molecular Biology, Inc.
The evolution of coenzyme Q
Authors: Crane Frederick L.
Published: April 2009

In the 50 years since the identification of coenzyme Q as an electron carrier in mitochondria, it has been identified with diverse and unexpected functions in cells. Its discovery came as a result of a search for electron carriers in mitochondria following the identification of flavin and cytochromes by Warburg, Keilin, Chance and others. As a result of investigation of membrane lipids at D.E. Green's laboratory at University of Wisconsin coenzyme Q was identified as the electron carrier between primary flavoprotein dehydrogenases and the cytochromes. Then Peter Mitchell identified the role of transmembrane proton transfer as a basis for ATP synthesis. The general distribution of coenzyme Q in all cell membranes then led to the recognition of a role as a primary antioxidant. The protonophoric function was extended to acidification of Golgi and lysosomal vericles. A further role in proton release through the plasma membrane and its relation to cell proliferation has not been fully developed. A role in generation of H2 O2 as a messenger for hormone and cytokine action is indicated as well as prevention of apoptosis by inhibition of ceramide release. Identification of the genes and proteins required for coenzyme Q synthesis has led to a basis for defining deficiency. For 50 years Karl Folkers has led the search for deficiency and therapeutic application. The development of large scale production, better formulation for uptake, and better methods for analysis have furthered this search. The story isn't over yet. Questions remain about effects on membrane structure, breakdown and control of cellular synthesis and uptake and the basis for therapeutic action.
Mitochondrial production of reactive oxygen species: Role of Complex I and quinone analogues
Authors: Fato Romana , Bergamini Christian , Leoni Serena , Lenaz Giorgio
Published: April 2009

Mitochondrial reactive oxygen species (ROS) are mainly produced by the respiratory chain enzymes. The sites for ROS production in mitochondrial respiratory chain are normally ascribed to the activity of Complex I and III. The presence of specific inhibitors modulates reactive oxygen species production in Complex I: inhibitors such as rotenone induce a strong ROS increase, while inhibitors such as stigmatellin prevent it. We have investigated the effect of hydrophilic quinones on Complex I ROS production in presence of different inhibitors. Some short chain quinones are Complex I inhibitors (CoQ2, idebenone and its derivatives), while CoQ1, decylubiquinone (DB) and duroquinone (DQ) are good electron acceptors from Complex I.

Our results show that the ability of short chain quinones to induce an oxidative stress depends on the site of interaction with Complex I and on their physical‐chemical characteristics. We can conclude that hydrophilic quinones may enhance oxidative stress by interaction with the electron escape sites on Complex I while more hydrophobic quinones can be reduced only at the physiological quinone reducing site without reacting with molecular oxygen.
NAD(P)H:quinone oxidoreductase (NQO1) loss of function in Burkitt's lymphoma cell lines
Authors: Brugè Francesca , Virgili Samantha , Cacciamani Tiziana , Principi Federica , Tiano Luca , Littarru Gian Paolo
Published: April 2009

Two‐electron reduction of quinones catalyzed by NAD(P)H:quinone oxidoreductase (NQO1) protects cells against oxidative stress and toxic quinones. In fact, low level of NQO1 activity is often associated with increased risk of developing different types of tumours and with toxic effects linked to environmental quinones. In a previous report we analyzed the relationship between the oxidative stress induced by UV radiation and CoQ10 content in Burkitt's lymphoma cell lines compared to HL‐60. The basal content of CoQ10 in Raji cells was slightly higher compared to HL‐60. Moreover, after irradiation or ubiquinone supplementation in the medium, reduced CoQ10 levels were higher in Raji and Daudi cells compared to HL‐60. In the present work, in order to inquire if NQO1 plays a role in the CoQ reducing capacity observed in the lymphoblastoid cell lines, we analyzed the transcription and translation products of this gene in Raji and Daudi cells, compared to cell lines possessing low and high NQO1 activity.

The amount of transcripts of this gene in lymphoblastoid cells was comparable to that observed in HL‐60 cells (low activity), as well as the level of two alternatively spliced mRNAs; one of which is described for the first time in this work. From the genotype analysis of polymorphisms C609T and C465T we observed that HL‐60, Raji and Daudi cells were all heterozygous. Furthermore, NQO1 enzyme activity and protein synthesis in the cytosol of Raji and Daudi cells were undetectable. Therefore in Burkitt's lymphoma cell lines the NQO1 gene is not efficiently translated and this effect is not related to (C609T) polymorphism. Further studies will be necessary to find the enzyme responsible for CoQ10 reducing activity observed in lymphoma cell lines. On the other hand, this result suggests a careful re‐evaluation of data concerning loss of NQO1 activity and polymorphisms in tumour cells.
Ubichromanol: A prodrug to support mitochondrial ubiquinone functions?
Authors: Gille Lars , Stamberg Werner , Gregor Wolfgang , Jäger Walter , Reznicek Gottfried , Netscher Thomas , Rosenau Thomas , Nohl Hans
Published: April 2009

Ubichromanol‐9 (UCa9, with a side chain consisting of nine isoprene units) is a reductive cyclization product of ubiquinone‐10 (UQ10). It acts as a radical scavenging antioxidant and is about half as effective as α‐tocopherol. Already decades ago its one‐electron oxidation product, the ubichromanoxyl radical had been identified. However, nothing was known so far about the two‐electron oxidation product of this antioxidant and its bioactivity. This study proves that ubichromanol can be oxidized to a ubiquinone‐like compound with a hydroxyl‐substituted side chain (UQ10 OH), a metabolite that is naturally present in bovine liver mitochondria.

The bioactivity of this ubiquinone derivative in its reduced form as substrate for mitochondrial complex III (cytochrome bc1 complex) was slightly below that of native ubiquinol, but significantly higher than that of reduced α‐tocopheryl quinone. Since ubiquinone‐like molecules (UQ10 OH, UQ10) were identified as oxidation products of UCa9 during lipid peroxidation, this ubiquinone derivative could provide a possibility to combine antioxidant properties of chromanols and bioenergetic benefits of UQ10.
Supplemental ubiquinol in patients with advanced congestive heart failure
Authors: Langsjoen Peter H. , Langsjoen Alena M.
Published: April 2009

Patients with CHF, NYHA class IV, often fail to achieve adequate plasma CoQ10 levels on supplemental ubiquinone at dosages up to 900 mg/day. These patients often have plasma total CoQ10 levels of less than 2.5 μg/ml and have limited clinical improvement. It is postulated that the intestinal edema in these critically ill patients may impair CoQ10 absorption. We identified seven patients with advanced CHF (mean EF 22%) with sub‐therapeutic plasma CoQ10 levels with mean level of 1.6 μg/ml on an average dose of 450 mg of ubiquinone daily (150–600 mg/day). All seven of these patients were changed to an average of 580 mg/day of ubiquinol (450–900 mg/day) with follow‐up plasma CoQ10 levels, clinical status, and EF measurements by echocardiography. Mean plasma CoQ10 levels increased from 1.6 μg/ml (0.9–2.0 μg/ml) up to 6.5 μg/ml (2.6–9.3 μg/ml). Mean EF improved from 22% (10–35%) up to 39% (10–60%) and clinical improvement has been remarkable with NYHA class improving from a mean of IV to a mean of II (I to III). Ubiquinol has dramatically improved absorption in patients with severe heart failure and the improvement in plasma CoQ10 levels is correlated with both clinical improvement and improvement in measurement of left ventricular function.
Oxidative stress, endothelial function and coenzyme Q10
Authors: Belardinelli Romualdo , Tiano Luca , Littarru Gian Paolo
Published: April 2009

Reactive oxygen species seem to play an important role in vascular homeostasis. In conditions of high oxidative stress, such as chronic heart failure and multiple coronary risk factors, the rate of inactivation of nitric oxide to peroxynitrite by superoxide anions may be reduced by CoQ10, which can also protect against nitrosative damage. CoQ10 may also influence vascular function indirectly via inhibition of oxidative damage to LDL. Patients with lower levels of extracellular superoxide dismutase (ecSOD) demonstrate greater improvements than patients with normal ec‐SOD levels, suggesting that the higher the oxidative stress the greater the improvement in the endothelium‐dependent relaxation after the administration of a compound with antioxidant properties like CoQ10. Future studies are needed to inquire whether these effects may translate into benefits in clinical practice.
Antiangiogenic and hypolipidemic activity of coenzyme Q10 supplementation to breast cancer patients undergoing Tamoxifen therapy
Authors: Sachdanandam Panchanatham
Published: April 2009

Tamoxifen, a non‐steroidal anti‐estrogen is now widely used and has led to an increase in both disease‐free and overall survival of women after primary surgery. Tamoxifen therapy is found to cause hypertriglyceridemia by reducing activity of lipolytic enzymes on triglycerides, and thereby increasing the risk of cardiovascular disease. Angiogenesis promotes local tumour progression and invasion and enables tumour cell dissemination and metastasis formation. Our study has found that co‐administration of Coenzyme Q10 (100 mg) along with tamoxifen (10 mg, twice a day) to breast cancer patients reduced the level of angiogenesis markers and lipid levels.
arNOX activity of saliva as a non‐invasive measure of coenzyme Q10 response in human trials
Authors: Morré D. James , Morré Dorothy M.
Published: April 2009

arNOX is a coenzyme Q10‐inhibited, aging‐related ECTO‐NOX protein of the cell surface also present in sera. It is capable of Superoxide generation measured as Superoxide dismutase‐inhibited reduction of ferricytochrome c and is a potential contributor to atherogenic risk. Here, we report an arNOX activity of saliva of older individuals also inhibited by coenzyme Q10. The activity first appears after age 30 to a near maximum at about age 55. Those surviving beyond age 55 usually have reduced arNOX activities. Our studies demonstrate significant (25 to 30%) reduction of arNOX levels with coenzyme Q10 supplementation of 60 mg (2 × 30 mg) per day for 28 days. Activity correlated with age. Response to coenzyme Q10 increased with age being greatest between ages 60 and 65. Saliva arNOX levels varied in a regular pattern throughout the day so it was important that samples be collected at approximately the same time each day for comparative purposes. The coenzyme Q10 response was reversible and within 12 h after the last intake of coenzyme Q10, the salivary arNOX levels returned to base line. The findings suggest that salivary arNOX provides a convenient and non‐invasive method to monitor arNOX levels in clinical coenzyme Q10 intervention trials with the response levels paralleling those seen with serum and cellular arNOX.
Mechanisms of inhibitory effects of CoQ10 on UVB‐induced wrinkle formation in vitro and in vivo
Authors: Inui M. , Ooe M. , Fujii K. , Matsunaka H. , Yoshida M. , Ichihashi M.
Published: April 2009

Photodamaged skin exhibits wrinkles, pigmented spots, dryness and tumors. Solar UV radiation induces cyclobutane pyrimidine dimers (CPD) and further produces base oxidation by reactive oxygen species (ROS). ROS are thought to be a major factor to initiate the up‐regulation of matrix metalloproteinases (MMPs) in keratinocytes and fibroblasts via activation of receptor proteins on the cell membrane of keratinocytes and fibroblasts, and to degrade fiber components in dermis, leading to wrinkle formation.

Coenzyme Q10 (CoQ10) was reported to reduce ROS production and DNA damage triggered by UVA irradiation in human keratinocytes in vitro. Further, CoQ10 was shown to reduce UVA‐induced MMPs in cultured human dermal fibroblasts. We speculated that UVB radiation‐induced cytokine production in keratinocytes may be inhibited by CoQ10, resulting in the reduction of MMPs in fibroblasts leading to wrinkle reduction. Our in vitro studies showed that UVB‐induced IL‐6 production of normal human keratinocyte (NHKC) decreased in the presence of CoQ10. Furthermore, MMP‐1 production of fibroblasts cultured with the medium containing CoQ10 collected from UVB‐irradiated NHKC significantly decreased during 24 h culture. In the clinical trial study, we found that the use of 1% CoQ10 cream for five months reduced wrinkle score grade observed by a dermatologist. Taken together, our results indicate that CoQ10 may inhibit the production of IL‐6 which stimulate fibroblasts in dermis by paracrine manner to up‐regulate MMPs production, and contribute to protecting dermal fiber components from degradation, leading to rejuvenation of wrinkled skin.
Improved HPLC column‐switching determination of coenzyme Q and Vitamin E in plasma
Authors: Bompadre Stefano , Tulipani Sara , Romandini Stefania , Giorgetti Raffaele , Battino Maurizio
Published: April 2009

A novel isocratic modified column‐switching HPLC method for automated quantitative analysis of Vitamin E and Coenzyme Q, in the reduced and oxidized form, is described. Many column‐switching HPLC methods are found in the literature, also for determining antioxidant substances, but we developed a different system of column‐switching. An empty column, 5 cm long, was connected to the switching valve, before the sample loop and the extraction column. The sample loop was connected directly after the empty column. The inserted column, containing about 1.4 ml of the extraction eluent simulated a gradient elution, enhancing sensitivity and resolution. When switching the columns, the empty column is placed right before the extraction column and acts as a static mixer for the extraction phase and the incoming analytical phase. Samples were cleaned from interfering compounds by transfer onto a extraction‐column, using a C‐8 silica. Separation was performed onto an analytical column C18 3 μm, 150 mm × 4.6 mm at a flow rate of 1.0 ml/min with 20 mmol/l lithium perchlorate/perchloric acid, pH3.0 in Ethanol as analytical eluent. Detection was performed with a ESA Coulochem 5100 A model. The method was found to be suitable for automated analysis of Coenzyme Q, reduced and oxidized form, and Vitamin E in serum.
Movements at the hemoglobin A‐hemes and their role in ligand binding, analyzed by X‐ray crystallography
Authors: Dodson Eleanor , Dodson Guy
Published: April 2009

The two hemoglobin structures determined by Max Perutz, the liganded R‐state, which has high oxygen affinity, and the unliganded T‐state with low oxygen affinity, were landmarks in molecular and structural biology (Perutz and Lehman, Nature 1968, 219, 902–909; Bolton and Perutz, Nature 1970, 28, 551–552; Perutz et al., Nature 1968, 219, 131–139). They provided the basis of a structural mechanism that connected beautifully to the theory of cooperativity in protein systems, formulated at about the same time by Monod et al. (J Mol Biol 1965, 12, 88–1118). Over the last 40 years there have been extensive biochemical and structural studies on hemoglobin's structure and the mechanisms that govern its co‐operativity, specificity, and other physiological properties. There are still however a number of unresolved issues over the molecule's properties, for example the mechanism responsible for the affects of pH on oxygen affinity, i.e., the Bohr and Root effects. In this communication the differences in the geometry at the a‐heme of unliganded and liganded human and the Antarctic fish (Trematomus) hemoglobin will be described and their relevance to affinity considered. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 1056–1063, 2009.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Glycerol‐induced folding of unstructured disulfide‐deficient lysozyme into a native‐like conformation
Authors: Sakamoto Keiko , Hirai Ken‐ichi , Kitamura Yoshiaki , Yamazaki Kouta , Yusa Mitsunobu , Tokunaga Naoki , Doi Gakuji , Noda Yasuo , Tachibana Hideki , Segawa Shin‐ichi
Published: April 2009

2SS[6‐127,64‐80] variant of lysozyme which has two disulfide bridges, Cys6‐Cys127 and Cys64‐Cys80, and lacks the other two disulfide bridges, Cys30‐Cys115 and Cys76‐Cys94, was quite unstructured in water, but a part of the polypeptide chain was gradually frozen into a native‐like conformation with increasing glycerol concentration. It was monitored from the protection factors of amide hydrogens against H/D exchange. In solution containing various concentrations of glycerol, H/D exchange reactions were carried out at pH* 3.0 and 4°C. Then, 1H‐15N‐HSQC spectra of partially deuterated protein were measured in a quenching buffer for H/D exchange (95% DMSO/5% D2O mixture at pH* 5.5 adjusted with dichloroacetate). In a solution of 10% glycerol, the protection factors were nearly equal to 10 at most of residues. With increasing glycerol concentration, some selected regions were further protected, and their protection factors reached about a 1000 in 30% glycerol solution. The highly protected residues were included in A‐, B‐, and C‐helices and β3‐strand, and especially centered on Ile 55 and Leu 56. In 2SS[6‐127,64‐80], long‐range interactions were recovered due to the preferential hydration by glycerol in the hydrophobic box of the α‐domain. Glycerol‐induced recovering of the native‐like structure is discussed from the viewpoint of molten globules growing with the protein folding. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 665–675, 2009.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Review: An overview about the structure–function relationship of marine sulfated homopolysaccharides with regular chemical structures
Authors: Pomin Vitor H.
Published: April 2009

Efforts in both structural and biological studies of sulfated polysaccharides from marine organisms have increased significantly over the last 10 years. Marine invertebrates have been demonstrated to be a source of glycans with particularly well‐defined chemical structures, although ordered structural patterns can also be found occasionally in algal sources such as red seaweeds. Clear and regular structural features are essential for a good understanding of the biological activities of these marine homopolysaccharides of which sulfated fucans and sulfated galactans are the most studied. Herein, the main structural features (sugar type, sulfation and glycosylation sites, and orientational binding preferences) of both sulfated fucans and galactans are individually reviewed with regard to their specific contributions to two frequently described biological functions: the acrosome reaction (a physiological event of sea‐urchin fertilization), and the anticoagulant and antithrombotic activities (an alternative and highly desirable pharmacological application). © 2009 Wiley Periodicals, Inc. Biopolymers 91: 601–609, 2009.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Identification of cell culture conditions to control N‐glycosylation site‐occupancy of recombinant glycoproteins expressed in CHO cells
Authors: Gawlitzek Martin , Estacio Michael , Fürch Tobias , Kiss Robert
Published: April 2009

The effect of different cell culture conditions on N‐glycosylation site‐occupancy has been elucidated for two different recombinant glycoproteins expressed in Chinese hamster ovary (CHO) cells, recombinant human tissue plasminogen activator (t‐PA) and a recombinant enzyme (glycoprotein 2—GP2). Both molecules contain a N‐glycosylation site that is variably occupied. Different environmental factors that affect the site‐occupancy (the degree of occupied sites) of these molecules were identified. Supplementing the culture medium with additional manganese or iron increased the fraction of fully occupied t‐PA (type I t‐PA) by approximately 2.5–4%. Decreasing the cultivation temperature from 37 to 33°C or 31°C gradually increased site‐occupancy of t‐PA up to 4%. The addition of a specific productivity enhancer, butyrate, further increased site‐occupancy by an additional 1% under each cultivation temperature tested. In addition, the thyroid hormones triiodothyronine and thyroxine increased site‐occupancy of t‐PA compared to control conditions by about 2%. In contrast, the addition of relevant nucleoside precursor molecules involved in N‐glycan biosynthesis (e.g., uridine, guanosine, mannose) either had no effect or slightly reduced site‐occupancy. For the recombinant enzyme (GP2), it was discovered that culture pH and the timing of butyrate addition can be used to control N‐glycan site‐occupancy within a specific range. An increase in culture pH correlated with a decrease in site‐occupancy. Similarly, delaying the timing for butyrate addition also decreased site‐occupancy of this molecule. These results highlight the importance of understanding how cell culture conditions and media components can affect the product quality of recombinant glycoproteins expressed in mammalian cell cultures. Furthermore, the identification of relevant factors will enable one to control product quality attributes, specifically N‐glycan site‐occupancy, within a specific range when applied appropriately. Biotechnol. Bioeng. 2009;103: 1164–1175. © 2009 Wiley Periodicals, Inc.
Equalizing growth in high‐throughput small scale cultivations via precultures operated in fed‐batch mode
Authors: Huber Robert , Scheidle Marco , Dittrich Barbara , Klee Doris , Büchs Jochen
Published: April 2009

An often underestimated problem when working with different clones in microtiter plates and shake flask screenings is the non‐parallel and non‐equal growth of batch cultures. These growth differences are caused by variances of individual clones regarding initial biomass concentration, lag‐phase or specific growth rate. Problems arising from unequal growth kinetics are different induction points in expression studies or uneven cultivation periods at the time of harvest. Screening for the best producing clones of a library under comparable conditions is thus often impractical or even impossible. A new approach to circumvent the problem of unequal growth kinetics of main cultures is the application of fed‐batch mode in precultures in microtiter plates and shake flasks. Fed‐batch operation in precultures is realized through a slow‐release system for glucose. After differently growing cultures turn to glucose‐limited growth, they all consume the same amount of glucose due to the fixed feed profile of glucose provided by the slow‐release system. This leads to equalized growth. Inherent advantages of this method are that it is easy to use and requires no additional equipment like pumps. This new technique for growth equalization in high‐throughput cultivations is simulated and verified experimentally. The growth of distinctly inoculated precultures in microtiter plates and shake flasks could be equalized for different microorganisms such as Escherichia coli and Hansenula polymorpha. Biotechnol. Bioeng. 2009;103: 1095–1102. © 2009 Wiley Periodicals, Inc.
On‐line adaptive metabolic flux analysis: Application to PHB production by mixed microbial cultures
Authors: Dias João , Pardelha Filipa , Eusébio Mário , Reis Maria A. M. , Oliveira Rui
Published: April 2009

In this work, an algorithm for on‐line adaptive metabolic flux analysis (MFA) is proposed and applied to polyhydroxybutyrate (PHB) production by mixed microbial cultures (MMC). In this process, population dynamics constitutes an important source of perturbation to MFA calculations because some stoichiometric and energetic parameters of the underlying metabolic network are continuously changing over time. The proposed algorithm is based on the application of the observer‐based estimator (OBE) to the central MFA equation, whereby the role of the OBE is to force the accumulation of intracellular metabolites to converge to zero by adjusting the values of unknown network parameters. The algorithm was implemented in a reactor equipped with on‐line analyses of dissolved oxygen and carbon dioxide through respirometric and titrimetric measurements. The oxygen and carbon dioxide fluxes were measured directly, whereas acetate, PHB, and sludge production fluxes were estimated indirectly using a projection of latent structures model calibrated a priori with off‐line measurements. The algorithm was implemented in a way that the network parameters associated with biosynthesis were adjusted on‐line. The algorithm proofed to converge exponentially with the steady state error always below 1 mmol/L. The estimated fluxes passed the consistency index test for experimental error variances as low as 1%. The comparison of measured and estimated respiratory coefficient and of the theoretical and estimated yield of sludge on acetate further confirmed the metabolic consistency of the parameters that were estimated on‐line. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Dinuclear Copper(II) Complexes of Macrocyclic Polyamines: Synthesis, Characterization, and DNA Cleavage
Authors: Huang Yu , Chen Shan‐Yong , Zhang Ji , Tan Xin‐Yu , Jiang Ning , Zhang Jing‐Jing , Zhang Yu , Lin Hong‐Hui , Yu Xiao‐Qi
Published: April 2009

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Two macrocyclic polyamine ligands and their dinuclear copper(II) (CuII) complexes were synthesized and characterized. In the complexes, two 1,4,7,10‐tetraazacyclododecane (cyclen) moieties were bridged by a dipeptide spacer, and CuII as metal ion was coordinated to the ligands to form the novel complexes. These complexes were characterized by UV/VIS, IR, EPR, and ESI‐MS analyses. The catalyzed DNA cleavage and DNA binding properties of these complexes were studied under physiological conditions. The effects of complex concentrations, cleavage time, and temperature on the DNA cleavage reactions were systematically investigated. The results strongly suggested that the plasmid DNA (pUC 19) can be cleaved by the dinuclear CuII complexes. At pH 7.0 and 37°, incubating DNA with the complexes for 24 h, all Form I was selectively converted into Form II. At 55°, pH 7.0, the time was shortened to less than 30 min. According to the mechanism experiment, these complexes cleave plasmid pUC19 DNA by oxidative mechanism. The synergistic effect of the CuII ions is important to improve the DNA cleavage.
Glycoalkaloids as Biomarkers for Recognition of Cultivated, Wild, and Somatic Hybrids of Potato
Authors: Savarese Salvatore , Andolfi Anna , Cimmino Alessio , Carputo Domenico , Frusciante Luigi , Evidente Antonio
Published: April 2009

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Cultivated and wild potato species synthesize a wide variety of steroidal glycoalkaloids (GAs). During breeding programs, species genomes are often put together through either sexual or somatic hybridization. Therefore, the determination of the GA composition of hybrids is very important in that it may affect either human consumption, or resistance to pathogen and pests. Here, we report the results of GA analysis performed on wild Solanum bulbocastanum, haploids of cultivated potato S. tuberosum and their interspecific somatic hybrids. GAs were extracted from tubers and analyzed by HPLC. HPLC Profile of S. tuberosum haploids showed, as expected, the presence of α‐solanine and α‐chaconine. The profile of S. bulbocastanum extract showed lack of α‐solanine and α‐chaconine, and the presence of four GAs. The GA pattern of the somatic hybrids was the sum of their parents' profile. This represents a noteworthy tool for their unequivocal recognition. Interestingly, two hybrids produced not only GAs of both parents but also new compounds to be further investigated. This provided evidence that somatic hybridization induced the synthesis of new metabolites. The nature of the probable unidentified GAs associated to S. bulbocastanum and its somatic hybrids was ascertained by chemical degradation and spectroscopic analysis of their aglycones and sugar moieties. Our results suggest their close relation with GAs of both wild and cultivated potato species.
Percutaneous retrieval of intravascular and intracardiac foreign bodies with a dedicated three‐dimensional snare: A 3‐year single center experience
Authors: Bonvini Robert F. , Rastan Aljoscha , Sixt Sebastian , Noory Elias , Beschorner Ulrich , Leppanen Olli , Mach François , Schwarzwälder Uwe , Bürgelin Karlheinz , Zeller Thomas
Published: April 2009

Introduction:

The presence of symptomatic or asymptomatic intravascular/intracardiac foreign body (FB) is under‐reported in the literature, but it is more commonly encountered in clinical practice. The implantation of long‐term venous catheters and the number of technical challenging endovascular procedures are both constantly increasing. Thus, the number of reported FBs will also increase, becoming a serious concern, especially once associated with a cardiovascular complication.

Materials and Methods:

We report the analysis of 22 patients in whom an intravascular/cardiac FBs retrieval was attempted. The details of the procedure have been discussed in depth emphasizing the technical aspects of the utilized dedicated three‐dimensional snare device (Entrio snare™). The technical feasibility, safety, and efficacy of the retrieval procedure were then analyzed.

Results:

We divided our patients into two groups. Group 1 included 12 patients in whom the FB had already migrated in the right heart or in the pulmonary circulation. Group 2 included 10 patients with an intravascular FB (intravenous or intraarterial). Technical retrieval success rate was 95.5% (21/22), with a 35‐min procedural mean time and no in‐hospital procedural‐related complications.

Conclusions:

Our data confirm that different kinds of FBs lodging in different sites of the cardiovascular system can safely and efficaciously be percutaneously retrieved by utilizing a dedicated three‐dimensional snare device. This, therefore, suggests that this minimally invasive intervention should be rapidly attempted, thus anticipating several serious complications. © 2009 Wiley‐Liss, Inc.
Useful Sialic Acid Modifications Catalyzed by Palladium
Authors: Chang Chih‐Wei , Norsikian Stéphanie , Beau Jean‐Marie
Published: April 2009

A regio‐ and stereocontrolled solution for a selective modification at the C‐2 or C‐4 position of N‐acetylneuraminic acid involves the use of allylic substitution catalyzed by palladium. As illustrated in the scheme, regioselective malonylation is under the strict influence of the ligands associated with the allylpalladium complex.

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The influence of information communications technology (ICT) on cash management and financial department performance: An explanatory model
Authors: San‐Jose Leire , Iturralde Txomin , Maseda Amaia
Published: April 2009

We delineated the extent to which various facets of information communications technology (ICT) are used and are perceived as useful by treasury managers, focusing on three indicators of financial department performance: cost savings, improvements in the quality of the information, and enhancements in the use of scenario simulations for decision making. Specifically, we examined the relationship between ICT use in cash management functions within financial departments, perceptions of the importance of cash management to treasury managers, and their perceptions of the usefulness of ICT to financial department performance. The theoretical and applied implications of these findings are discussed. Copyright © 2009 ASAC. Published by John Wiley & Sons, Ltd.
Effects of Statins on Endothelial Function in Patients with Coronary Artery Disease
Authors: Simova Iana I. , Denchev Stefan V. , Dimitrov Simeon I.
Published: April 2009

Background

Flow‐mediated dilatation (FMD) of the brachial artery is a method capable of detecting endothelium dysfunction. Statins are generally consent drugs for reducing cardiovascular morbidity and mortality and are shown to improve the systemic endothelial function.

Hypothesis

The aim of our study was to assess the endothelial function using FMD of the brachial artery in patients with different degrees of coronary artery stenosis with respect to their treatment with statins.

Methods

We evaluated the FMD of 221 patients with coronary arteriography performed, of whom 99 (44.8%) were receiving statins and 122 (55.2%) were not receiving statins.

Results

We did not find a statistically significant difference in the FMD values between the patients with and without a statin treatment: 5.57 ± 5.68 and 4.69 ± 4.48, respectively, P = .581. In the subgroup of patients without angiographically visible coronary artery stenoses or with stenoses <20% (86 patients), patients undergoing statin treatment had a significantly better endothelial function compared to patients without such a treatment: FMD 9.24 ± 6.87 and 6.50 ± 4.51, respectively, P = .047.

Conclusions

FMD could not distinguish between the patients who were treated with statin and those not treated with statins with the same demographic, clinical, and angiographic characteristics. The only exception was in the group of patients with a minor coronary disease. Statin treatment had a more pronounced effect in the earlier stages of coronary atherosclerosis. Copyright © 2009 Wiley Periodicals, Inc.
Serum Oxidative Stress Level Correlates with Clinical Parameters in Chronic Systolic Heart Failure Patients
Authors: Amir Offer , Paz Hagar , Rogowski Ori , Barshai Marina , Sagiv Moran , Shnizer Sergei , Reznick Abraham Z. , Amir Ruthie E.
Published: April 2009

Background

Serum oxidative stress (OS) level has an important role in the inflammatory process of heart failure.

Hypothesis

The study was designed to analyze serum OS levels in chronic heart failure (HF) patients and to examine the relation between OS levels and other clinical and prognostic parameters of HF.

Methods

We studied 82 consecutive chronic symptomatic HF patients with systolic LV dysfunction (ejection fraction <45%). The serum OS level was determined using thermochemiluminescence assay. We compared the serum OS levels with patients' clinical and prognostic parameters.

Results

Higher serum OS levels were associated with higher New York Heart Association class (P = .01), worse renal function (serum urea, creatinine, and creatinine clearance) (P<.001) and higher serum levels of hs‐C‐reactive protein and N‐terminal pro brain natriuretic peptide (P = .001, P<.001, respectively).

Conclusions

In chronic systolic HF patients, high serum OS levels correlate with advanced disease and known markers of poor prognosis. Copyright © 2009 Wiley Periodicals, Inc.