bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Identification of a New Cytotoxic Biflavanone from Selaginella doederleinii.
Authors: Lee Na‐Youn , Min Hye‐Young , Lee Jun , Nam Joo‐Won , Lee Yoo‐Jin , Han Ah‐Reum , Wiryawan Adam , Suprapto Wahyu , Lee Sang Kook , Seo Eun‐Kyoung
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Semisynthesis and Antitumoral Activity of 2‐Acetylfuranonaphthoquinone and Other Naphthoquinone Derivatives from Lapachol.
Authors: Eyong Kenneth O. , Kumar Ponminor S. , Kuete Victor , Folefoc Gabriel N. , Nkengfack Ephriam A. , Baskaran Sundarababu
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Instantaneous Synthesis of Stable Zerovalent Metal Nanoparticles under Standard Reaction Conditions.
Authors: Valle‐Orta Maiby , Diaz David , Santiago‐Jacinto Patricia , Vazquez‐Olmos America , Reguera Edilso
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Determination of a New Type of Phosphodiesterase‐5 Inhibitor, Thioquinapiperifil, in a Dietary Supplement Promoted for Sexual Enhancement.
Authors: Uchiyama Nahoko , Saisho Kazuhiro , Kikura‐Hanajiri Ruri , Haishima Yuji , Goda Yukihiro
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Ferromagnetism and Possible Application in Spintronics of Transition‐Metal‐Doped ZnO Films
Authors: Pan F. , Song C. , Liu X. J. , Yang Y. C. , Zeng F.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Structures of Quasicrystals: Where Are the Atoms?
Authors: Gratias D. , Quiquandon M.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Graphitic Carbon Nitride Materials: Variation of Structure and Morphology and Their Use as Metal‐Free Catalysts
Authors: Thomas Arne , Fischer Anna , Goettmann Frederic , Antonietti Markus , Mueller Jens‐Oliver , Schloegl Robert , Carlsson Johan M.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Review on Mn Based Materials for Magnetic Refrigeration: Structure and Properties
Authors: Brueck E. , Tegus O. , Cam Thanh D. T. , Trung Nguyen T. , Buschow K. H. J.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Cyclic Metalated Nitriles: Stereoselective Cyclizations to cis‐ and trans‐Hydrindans, Decalins, and Bicyclo[4.3.0]undecanes
Authors: Fleming Fraser F. , Gudipati Subramanyham
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Survey of Briarane‐Type Diterpenoids. Part 3.
Authors: Sung Ping‐Jyun , et al. et al.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Alk‐1‐enyl Azides
Authors: Collier S. J.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: N‐Borylenamines
Authors: Collier S. J.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Enamines
Authors: Sammakia T. , Abramite J. A. , Sammons M. F.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Selective Conversion of Hydrocarbons with H2O2 Using Biomimetic Non‐Heme Iron and Manganese Oxidation Catalysts
Authors: Tanase Stefania , Bouwman Elisabeth
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Diversity‐Based Approaches to Selective Biomimetic Oxidation Catalysis
Authors: Berkessel Albrecht
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Simple and Chelate Enolate Claisen Rearrangement
Authors: Kulkarni Mukund G.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Advances in the Development of Methods for the Application of Carbocation Chemistry
Authors: McClelland R. A.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Metal‐Catalyzed Cycloisomerization Reactions of Functionalized Alkynes
Authors: Michelet Veronique
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Growing Synthetic Utility of the Weinreb Amide
Authors: Balasubramaniam Sivaraman , Aidhen Indrapal Singh
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Asymmetric Baylis—Hillman Reaction: An Enchanting Expedition
Authors: Krishna Palakodety Radha , Sachwani Rachna , Reddy Purumandla Srinivas
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Isotopic Labeling in the Study of Organic and Organometallic Mechanism and Structure
Authors: Lloyd‐Jones Guy C. , Munoz M. Paz
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Ring Expansions and Contractions of Metalloporphyrins
Authors: Callot Henry J.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Development of a Method for the Solid‐Phase Peptide Synthesis in Water
Authors: Hojo Keiko , Ichikawa Hideki , Fukumori Yoshinobu , Kawasaki Koichi
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Sucrose Chemistry and Applications of Sucrochemicals
Authors: Queneau Yves , Jarosz Slawomir , Lewandowski Bartosz , Fitremann Juliette
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Deoxy Sugars — Occurrence and Synthesis
Authors: de Lederkremer Rosa M. , Marino Carla
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Biocatalytic C—C Bond Formation in Asymmetric Synthesis
Authors: Fessner Wolf‐Dieter
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Cyclodextrin Catalysis
Authors: Komiyama Makoto , Monflier Eric
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Alkaloids
Authors: Woolley Jack G.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Lower Terpenoids
Authors: Harborne Jeffrey B.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Design, Synthesis and Applications of Hyaluronic Acid—Paclitaxel Bioconjugates
Authors: Leonelli Francesca , La Bella Angela , Migneco Luisa Maria , Bettolo Rinaldo Marini
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Preparation, Structure, and Biological Properties of Phosphorus Heterocycles with a C—P Ring System
Authors: Yamashita Mitsuji
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Silicon Diols: Effective Inhibitors of Human Leukocyte Elastase
Authors: Showell Graham A. , Montana John G. , Chadwick Jenny A. , Higgs Chris , Hunt Hazel J. , MacKenzie Robert E. , Price Steve , Wilkinson Tina J.
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Norbornylsilanes: New Organosilicon Protecting Groups
Authors: Heldmann Dieter K. , Stohrer Juergen , Zauner Rafael
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Metallosilanols and Metallosiloxanes. Part 32. Synthesis and Reactivity of Silicon Transition Metal Complexes. Part 61. Synthesis and Reactivity of Polychlorinated Metallosiloxanes
Authors: Schumacher Dirk , Malisch Wolfgang , Soeger Nicola , Binnewies Michael
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Metallosilanols and Metallosiloxanes. Part 33. Synthesis and Reactivity of Silicon Transition Metal Complexes. Part 62. Half‐Sandwich Iron Complexes with a Silanol‐Functionalized Cyclopentadienyl Ligand
Authors: Sohns Andreas , Schumacher Dirk , Malisch Wolfgang , Nieger Martin
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Allosteric Regulation of Proteases
Authors: Hauske Patrick , Ottmann Christian , Meltzer Michael , Ehrmann Michael , Kaiser Markus
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Protein Data Bank (PDB), Its Related Services and Software Tools as Key Components for in silico Guided Drug Discovery
Authors: Kirchmair Johannes , Markt Patrick , Distinto Simona , Schuster Daniela , Spitzer Gudrun M. , Liedl Klaus R. , Langer Thierry , Wolber Gerhard
Published: February 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Natural alkaloids and synthetic relatives as chiral templates of the Orito's reaction
Authors: Tálas Emília , Margitfalvi József L.
Published: February 2009

The enantioselective hydrogenation of methyl or ethyl pyruvate over cinchona‐platinum catalyst system (Orito's reaction) is one of the most intensively studied heterogeneous catalytic asymmetric hydrogenation reactions. Studies aiming at systematic changes of the chiral template have played a crucial role in creating hypotheses for the mechanism of Orito's reaction. It is very important to clarify which structural unit of the alkaloid takes part in the enantiodifferentiation, and learn about the role of the different structural units of chiral templates. In this article, we made an attempt to describe the behavior of natural alkaloids, their synthetic derivatives, and analogues as chiral templates in the heterogeneous catalytic asymmetric hydrogenation of activated ketones. Chirality, 2010. © 2009 Wiley‐Liss, Inc.
Racial disparities for uterine corpus tumors
Authors: Wright Jason D. , Fiorelli Jessica , Schiff Peter B. , Burke William M. , Kansler Amanda L. , Cohen Carmel J. , Herzog Thomas J.
Published: February 2009

BACKGROUND:

Black women with endometrial cancer have been more likely to die than white patients. The authors examined factors associated with the poor outcome for black women with uterine corpus tumors and analyzed whether these characteristics have changed over time based on year of diagnosis.

METHODS:

The authors examined women with uterine neoplasms recorded from 1988‐2004 in the Surveillance, Epidemiology and End Results (SEER) Database. The authors developed Cox proportional hazards models to examine the effect of race on survival and stratified women by year of diagnosis into 3 groups: 1988‐1993, 1994‐1998, 1999‐2004.

RESULTS:

A total of 80,915 patients including 5564 (7%) black women were identified. Black patients were significantly younger, had more advanced stage tumors, and had more aggressive, nonendometrioid histologic variants (P < .001). Black women were 60% more likely to die from their tumors than white women when matched for other prognostic variables (hazards ratio, 1.60; 95% confidence interval, 1.51‐1.69). For each of the 3 time periods, survival was worse for blacks even when stratified by stage and histology. Over time, the incidence of serous and clear‐cell tumors increased, and the use of radiation decreased for both races. Staging lymphadenectomy was performed more commonly in both blacks (45%) and whites (48%) who had been treated more recently.

CONCLUSIONS:

Black women with uterine corpus tumors were more likely to die from their disease. This survival difference has persisted over time. The clinical characteristics of blacks and whites have remained relatively constant. The proportion of women who undergo surgical staging has increased with time and was well matched between races. Cancer 2009. © 2009 American Cancer Society.
Probing the Ignored Elimination Channel of Br2 in the 248 nm Photodissociation of 1,1‐Dibromoethylene by Cavity Ring‐Down Absorption Spectroscopy
Authors: Lee Ping‐Chen , Tsai Po‐Yu , Hsiao Ming‐Kai , Lin King‐Chuen , Huang C. H. , Chang A. H. H.
Published: February 2009

A process of elimination: Optical spectra of the Br2 product eliminated from the photodissociation of 1,1‐dibromoethylene at 248 nm are obtained (see picture), and the subsequent dissociation pathways are proposed with the aid of ab initio potential energy calculations. The behavior of the compound is compared with that of 1,2‐dibromoethylene.

magnified image

In the photodissociation of 1,1‐C2H2Br2 at 248 nm, the Br2 elimination channel is probed by using cavity ring‐down absorption spectroscopy (CRDS). In terms of spectral simulation, the vibrational population ratio of Br2(v=1)/Br2(v=0) is found to be 0.55±0.05, which indicates that the Br2 fragment is vibrationally hot. The rotational population is thermally equilibrated with a Boltzmann temperature of 349±38 K. According to ab initio potential energy calculations, the obtained fragments are anticipated to result primarily from photodissociation of the ground electronic state that undergoes 1) H migration followed by three‐center elimination, and 2) isomerization forming either trans‐ or cis‐1,2‐C2H2Br2 from which Br2 is eliminated. RRKM calculations predict that the Br2 dissociation rates through the ground singlet state prevail over those through the triplet state. Measurements of temperature and Ar pressure dependence are examined to support the proposed pathway via internal conversion. The quantum yield for the Br2 elimination reaction is determined to be 0.07±0.04. This result is smaller than that obtained in 1,2‐C2H2Br2, probably because the dissociation rates are slowed in the isomerization stage.
Development of CE methods to analyze potential components of the angiogenic glycoprotein vascular endothelial growth factor 165
Authors: Ongay Sara , Puerta Angel , Díez‐Masa Jose Carlos , Bergquist Jonas , de Frutos Mercedes
Published: February 2009

The vascular endothelial growth factor 165 (VEGF165) is the predominant form of the complex VEGF family. This glycoprotein has, among others, an angiogenic effect in many physiological and pathological events. For this reason, its roles as a biomarker and as a therapeutic drug have been considered. However, very little is known about the existence of different forms of VEGF165 arising from glycosylation and other potential PTMs. This aspect is crucial because it is known that for other glycoproteins the ratio between these isoforms actually acts as a biomarker for certain diseases and other physiological states. In addition, for therapeutic use of glycoproteins it is known that the biological activity may differ for the various isoforms. In this work CE methods to separate up to seven peaks without baseline resolution containing various forms of VEGF165 are developed. Using a computer program previously developed in‐house peak assignment could be performed with accuracy close to 100%. In this way, comparison between recombinant human VEGF165 expressed in insect cells, which is a glycosylating system, and in Escherichia coli cells, which are unable of performing glycosylation of proteins, has been possible. The methods developed, besides providing information about the existence of several forms of VEGF165, mean a starting point that permits the study of the role of VEGF165 as a potential biomarker of different diseases and physiological processes and to perform quality control of the recombinant drug during manufacturing. To the best of our knowledge this is the first time that CE methods for VEGF165 have been developed.
CE separation of various analytes of biological origin using polyether ether ketone capillaries and contactless conductivity detection
Authors: Knjazeva Tatjana , Kulp Maria , Kaljurand Mihkel
Published: February 2009

The development of efficient and sensitive analytical methods for the separation, identification and quantification of complex biological samples is continuously a topic of high interest in biological science. In the present study, the possibility of using a polyether ether ketone (PEEK) capillary for the CE separation of peptides, proteins and other biological samples was examined. The performance of the tubing was compared with that of traditional silica capillaries. The CE analysis was performed using contactless conductivity detection (C4D), which eliminated any need for the detection window and was suitable for the detection of optically inactive compounds. In the PEEK capillary the cathodic EOF was low and of excellent stability even at extremes pH. In view of this fast biological anions were analyzed using an opposite end injection technique without compromising separation. A comparison of the performances of fused‐silica and polymer capillaries during the separation of model sample mixtures demonstrated the efficiency and separation resolution of the latter to be higher and the reproducibility of the migration times and peak areas is better. Furthermore, PEEK capillaries allowed using simple experimental conditions without any complicated modification of the capillary surface or use of an intricate buffer composition. The PEEK capillaries are considered as an attractive alternative to the traditional fused‐silica capillaries and may be used for the analysis of complex biological mixtures as well as for developing portable devices.
Investigation of the stereodynamics of tris‐(α‐diimine)–transition metal complexes by enantioselective dynamic MEKC
Authors: Bremer Sabrina , Trapp Oliver
Published: February 2009

Enantiomerization of octahedral tris(α‐diimine)–transition metal complexes was investigated by enantioselective dynamic MEKC. Varying both the transition metal ion (Fe2+, Fe3+, and Ni2+) and the bidentate diimine ligand (1,10‐phenanthroline and 2,2′‐bipyridyl), the enantiomer separations were performed either in a 100 mM sodium tetraborate buffer (pH 9.3) or in a 100 mM sodium tetraborate/sodium dihydrogenphosphate buffer (pH 8.0) both containing sodium cholate as chiral surfactant. The unified equation of dynamic chromatography was employed to determine apparent reaction rate constants from the electropherograms showing distinct plateau formation. Apparent activation parameters ΔH‡ and ΔS‡ were calculated from temperature‐dependent measurements between 10.0 and 35.0°C in 2.5 K steps. It was found that the nature of the central metal ion and the ligand strongly influence the enantiomerization barrier. Surprisingly, complexes containing the 2,2′‐bipyridyl ligand show highly negative activation entropies between −103 and −116 J (K mol)−1 while the activation entropy of tris(1,10‐phenanthroline) complexes is positive indicating a different mechanism of interconversion. Furthermore, it was found that the Ni2+ complexes are stereostable under the conditions investigated here making them a lucent target as enantioselective catalysts.
Hepatocyte expression of serum response factor is essential for liver function, hepatocyte proliferation and survival, and postnatal body growth in mice #
Authors: Sun Kai , Battle Michele A. , Misra Ravi P. , Duncan Stephen A.
Published: February 2009

Serum response factor (SRF) is a transcription factor that binds to a CarG box motif within the serum response element of genes that are expressed in response to mitogens. SRF plays essential roles in muscle and nervous system development; however, little is known about the role of SRF during liver growth and function. To examine the function of SRF in the liver, we generated mice in which the Srf gene was specifically disrupted in hepatocytes. The survival of mice lacking hepatic SRF activity was lower than that of control mice; moreover, surviving mutant mice had lower blood glucose and triglyceride levels compared with control mice. In addition, Srf

loxP/loxP

AlfpCre mice were smaller and had severely depressed levels of serum insulin-like growth factor 1 (IGF-1). Srf-deficient livers were also smaller than control livers, and liver cell proliferation and viability were compromised. Gene array analysis of SRF depleted livers revealed a reduction in many messenger RNAs, including those encoding components of the growth hormone/IGF-1 pathway, cyclins, several metabolic regulators, and cytochrome p450 enzymes. Conclusion: SRF is essential for hepatocyte proliferation and survival, liver function, and control of postnatal body growth by regulating hepatocyte gene expression. (Hepatology 2009.)
Endotoxin uptake in mouse liver is blocked by endotoxin pretreatment through a suppressor of cytokine signaling-1–dependent mechanism #
Authors: Scott Melanie J. , Liu Shubing , Shapiro Richard A. , Vodovotz Yoram , Billiar Timothy R.
Published: February 2009

The liver is the main organ that clears lipopolysaccharide (LPS) and hepatocytes are a major cell-type involved in LPS uptake. LPS tolerance, or desensitization, is important in negative regulation of responses to LPS, but little is known about its mechanisms in hepatocytes. Primary isolated C57BL/6 hepatocytes, and liver in vivo, internalized fluorescent LPS, and this was dependent on Toll-like receptor 4 (TLR4) at the cell surface but not on TLR4-TIR signaling through MyD88. LPS clearance from plasma was also TLR4-dependent. Pretreatment of C57BL/6 hepatocytes with LPS prevented uptake of LPS 24 hours later and this LPS-mediated suppression was dependent on TLR4 signaling through MyD88. Many regulators of TLR4 signaling have been identified and implicated in LPS desensitization, including suppressor of cytokine signaling 1 (SOCS1). SOCS1 mRNA and protein expression increased after LPS stimulation in hepatocytes and in whole liver. LPS uptake in hepatocytes and liver was significantly reduced following infection with adenoviral vectors overexpressing SOCS1. Similarly, inhibition of SOCS1 using small interfering (si)RNA-mediated knockdown prevented LPS desensitization in hepatocytes. SOCS1 is known to interact with Toll/IL-1 receptor associated protein (TIRAP) and cause TIRAP ubiquitination and degradation, which regulates TLR signaling. We have also shown previously that TIRAP regulates LPS uptake in hepatocytes. SOCS1 coimmunoprecipitated with TIRAP in wild type hepatocyte cell lysates up to 8 hours after LPS stimulation, but not at later times. In the same samples, ubiquitinated TIRAP was detected after 4 hours and up to 8 hours after LPS stimulation, but not at later times. Conclusion: These data indicate hepatocytes are desensitized by LPS in a TLR4 signaling-dependent manner. LPS-induced SOCS1 upregulation increases degradation of TIRAP and prevents subsequent LPS uptake. The exploitation of these mechanisms of LPS desensitization in the liver may be important in future sepsis therapies. (Hepatology 2009.)
Microbiological or chemical models of enamel secondary caries compared by polarized‐light microscopy and energy dispersive X‐ray spectroscopy
Authors: Paradella Thaís Cachuté , de Sousa Fernando Augusto Cervantes Garcia , Koga‐Ito Cristiane Yumi , Jorge Antonio Olavo Cardoso
Published: February 2009

Different secondary caries models may present different results. The purpose of this study was to compare different in vitro secondary caries models, evaluating the obtained results by polarized‐light microscopy (PLM), scanning electron microscopy (SEM), and energy dispersive X‐ray spectroscopy (EDS). Standardized human enamel specimens (n = 12) restored with different materials (Z250 conventional composite resin–CRZ, Freedom polyacid‐modified composite resin–CRF, Vitremer resin‐modified glass‐ionomer–GIV, and Fuji IX conventional glass‐ionomer cement–GIF) were submitted to microbiological (MM) or chemical caries models (CM). The control group was not submitted to any caries model. For MM, specimens were immersed firstly in sucrose broth inoculated with Streptococcus mutans ATCC 35688, incubated at 37°C/5% CO2 for 14 days and then in remineralizing solution for 14 days. For CM, specimens were submitted to chemical pH‐cycling. Specimens were ground, submitted to PLM and then were dehydrated, gold‐sputtered and submitted to SEM and EDS. Results were statistically analyzed by Kruskall‐Wallis and Student‐Newman‐Keuls tests (α = 0.05). No differences between in vitro caries models were found. Morphological differences in enamel demineralization were found between composite resin and polyacid‐modified composite resin (CRZ and CRF) and between the resin‐modified glass‐ionomer and the glass‐ionomer cement (GIF and GIV). GIF showed higher calcium concentration and less demineralization, differing from the other materials. In conclusion, the glass‐ionomer cement showed less caries formation under both in vitro caries models evaluated. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Type I collagen gel in seeding medium improves murine mesencymal stem cell loading onto the scaffold, increases their subsequent proliferation, and enhances culture mineralization
Authors: Eslaminejad Mohamadreza Baghaban , Mirzadeh Hamid , Nickmahzar Aghbibi , Mohamadi Yossef , Mivehchi Houri
Published: February 2009

Collagen I as a major organic component of bone matrix may be important for establishment and maintenance of mesenchymal stem cells (MSCs) in osteogenic 3D culture. To explore this subject, murine marrow‐derived MSCs were seeded onto hybrid scaffolds of alginate/gelatin/β‐tricalcium phosphate in a medium either with or without collagen I gel. The cultures were then provided with osteogenic medium and incubated for three weeks during which loading efficiency, cell proliferation and the culture mineralization were quantified and statistically compared. According to the findings, in culture with collagen, although about 60% of the cells left the scaffolds, the remaining cells, however, proliferated extensively with a population doubling number (PDN) equivalent to 2.46 ± 0.31 and organized as cell aggregations that were heavily mineralized (calcium concentration = 1.017 ± 0.141 mM per scaffold), whereas in the culture without collagen, about 75% of the cells left the scaffolds, less cell proliferation occurred (PDN = 1.48 ± 0.29) and no cell aggregation was observed. The calcium concentration in this culture was 0.185 ± 0.029 mM per scaffold. All these differences were statistically significant (p < 0.001). Taken together, these data suggested that using the collagen I in seeding medium could help mMSCs loading into the scaffold, enhance their subsequent proliferation, and increase calcium deposition in 3D culture system. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Characterization of RNA primers synthesized by the human breast cancer cell DNA synthesome
Authors: Dai Heqiao , Liu Jianying , Malkas Linda H. , Hickey Robert J.
Published: February 2009

We previously reported on the purification and characterization of a functional multi‐protein DNA replication complex (the DNA synthesome) from human cells and tissues. The synthesome is fully competent to carry‐out all phases of the DNA replication process in vitro. In this study, DNA primase, a component of the synthesome, is examined to determine its activity and processivity in the in vitro synthesis and extension of RNA primers. Our results show that primase activity in the P4 fraction of the synthesome is 30‐fold higher than that of crude cell extracts. The synthesome synthesizes RNA primers that are 7–10 ribonucleotides long and DNA primers that are 20–40 deoxyribonucleotides long using a poly(dT) template of exogenous single‐stranded DNA. The synthesome‐catalyzed RNA primers can be elongated by E. coli DNA polymerase I to form the complementary DNA strands on the poly(dT) template. In addition, the synthesome also supports the synthesis of native RNA primers in vitro using an endogenous supercoiled double‐stranded DNA template. Gel analysis demonstrates that native RNA primers are oligoribonucleotides of 10–20 nt in length and the primers are covalently link to DNA to form RNA‐primed nascent DNA of 100–200 nt. Our study reveals that the synthesome model is capable of priming and continuing DNA replication. The ability of the synthesome to synthesize and extend RNA primers in vitro elucidates the organizational and functional properties of the synthesome as a potentially useful replication apparatus to study the function of primase and the interaction of primase with other replication proteins. J. Cell. Biochem. 106: 798–811, 2009. © 2009 Wiley‐Liss, Inc.
Putting chromatin immunoprecipitation into context
Authors: Zecchini Vincent , Mills Ian G.
Published: February 2009

Chromatin immunoprecipitation (ChIP), when paired with sequencing or arrays, has become a method of choice for the unbiased identification of genomic‐binding sites for transcription factors and epigenetic marks in various model systems. The data generated is often then interpreted by groups seeking to link these binding sites to the expression of adjacent or distal genes, and more broadly to the evolution of species, cell fate/differentiation or even cancer development. Against this backdrop is an ongoing debate over the relative importance DNA sequence versus chromatin structure and modification in the regulation of gene expression (Anon. 2008a Nature 454: 795; Anon. 2008b Nature 454: 711–715; Henikoff et al. 2008 Science 322: 853; Madhani et al. 2008 Science 322: 43–44). Rationally there is a synergy between the two and the goal of a biologist is to characterise both comprehensively enough to explain a cellular phenotype or a developmental process. If this is truly our goal then the critical factor in good science is an awareness of the constraints and potential of the biological models used. The reality however is often that this discussion is polarised by funding imperatives and the need to align to a transcription factor or epigenetic camp. This article will discuss the extrapolations involved in using ChIP data to draw conclusions about these themes and the discoveries that have resulted. J. Cell. Biochem. 107: 19–29, 2009. © 2009 Wiley‐Liss, Inc.
Size exclusion chromatography coupled to electrospray ionization mass spectrometry for analysis and quantitative characterization of arsenic interactions with peptides and proteins
Authors: Schmidt Anne‐Christine , Fahlbusch Benjamin , Otto Matthias
Published: February 2009

Arsenic‐binding proteins are of toxicological importance since enzymatic activities can be blocked by arsenic interactions. In the present work, a novel methodology based on size exclusion chromatography coupled to electrospray ionization mass spectrometry (SEC‐ESI‐MS) was developed with special emphasis to preserve the intact proteins and their arsenic bindings. The eluent composition of 25 mMTris/HCl, pH 7.5, with the addition of 100‐mM NaCl optimized for SEC with UV detection provided the highest SEC separation efficiency, but was not compatible with the ESI‐MS because of the non‐volatility of the buffer substance and of the salt additive. In order to find the best compromise between chromatographic separation and ionization of the arsenic‐binding proteins, buffer type and concentration, pH value, portion of organic solvent in the SEC eluent as well as the flow rate were varied. In the optimized procedure five different arsenic‐binding peptides and proteins (glutathione, oxytocin, aprotinin, α‐lactalbumin, thioredoxin) covering a molar mass range of 0.3–14 kDa could be analyzed using 75% 10‐mM ammonium formate, pH 5.0/25% acetonitrile (v : v) as eluent and a turbo ion spray source operated at 300 °C and 5.5 kV. A complete differentiation of all peptides and proteins involved in the arsenic‐binding studies as well as of their arsenic‐bound forms has become feasible by means of the extracted ion chromatograms (XIC) of the mass spectrometric detection. The new method offered the possibility to estimate equilibrium constants for the reaction of phenylarsine oxide with different thiol‐containing biomolecules by means of the XIC peak areas of reactants and products. Limits of detection in the range of 2–10 µM were obtained by SEC‐ESI‐MS for the individual proteins. Copyright © 2009 John Wiley & Sons, Ltd.
A reanalysis climatology of cool‐season tornado environments over southern Australia
Authors: Kounkou R. , Mills G. , Timbal B.
Published: February 2009

It is of great interest to assess the likely changes in occurrence of extreme weather events such as those associated with severe convective storms in future (changed) climates. However, while events such as tornadoes cannot be resolved by climate models, or even the higher‐resolution operational numerical weather prediction (NWP) models, it has been shown that some of the environments in which they occur can be predicted. In Australia, the so‐called cool‐season tornado (CST) environment is defined as the area where the forecast 700 hPa Surface Lifted Index and the surface to 1‐km vertical wind shear exceed specified thresholds. CST threat area forecasts are issued with each operational mesoscale NWP forecast by the Australian Bureau of Meteorology. In this paper, the application of this diagnostic indicator of CST occurrence to typical climate model resolutions is tested using the NCEP/NCAR and ERA‐40 reanalysis data sets. The techniques used to apply the diagnostic to these data sets are described, together with the calibration necessary to specify separate thresholds for each analysis set. Using these thresholds 40‐year climatologies of CST risk over Australia are constructed for each reanalysis data set. It is shown that the two data sets indicate very similar spatial distributions of risk. Trends in frequency of occurrence are problematic, with significant discontinuities in frequency after the introduction of satellite sounding data in 1979, with an increased frequency, but little trend in numbers, of CST environments since that time. Relating inter‐annual variations in the frequency of CST environments to large‐scale circulation indices show little relation with regional sea surface temperature anomalies or with the Southern Oscillation Index, but showed significant negative correlation with the Southern Annular Mode Index. Copyright © 2009 Royal Meteorological Society
Use of the standardized precipitation index (SPI) and a modified SPI for shaping the drought probabilities over Turkey
Authors: Türkeş Murat , Tatlı Hasan
Published: February 2009

This paper suggests a new methodology for the Standardized Precipitation Index (SPI), for studying different aspects of drought events in Turkey, including intensity, frequency and identifying the spatial and temporal patterns. The classical SPI is locally defined; for instance, for monthly scale or running means, a drought event would begin when the precipitation amount is below its long‐term average. However, the proposed method considers the local‐time means of the precipitation series by fitting an upper and a lower envelope to precipitation data to obtain the SPI values, thus it explicitly assesses a dry (or wet) spell of weather.

When we consider the climatological/meteorological features of precipitation and the physical geographical controls of the climate over Turkey, it is found that the proposed method is more capable of estimating the probability of dry or wet conditions for a station's monthly precipitation totals (or running means) than if the SPI values are obtained using the classical method. Comparisons of the probability values calculated for the long‐term series and various time scales have revealed that the proposed method successfully estimates and/or well represents the various precipitation anomalies, particularly the wet and dry extremes. For instance, the probabilities of monthly values obtained by the proposed SPI method being above normal, below normal, near normal (i.e. normal) and extremely dry are more realistic and reasonable than those found by the classical SPI method. In conclusion, one can apply the proposed SPI methodology for determining and monitoring droughts of other semi‐arid, dry sub‐humid and semi‐humid climate regions, where the precipitation series show high seasonality and year‐to‐year variability, such as in the Mediterranean macro‐climate region. Copyright © 2009 Royal Meteorological Society
Climatic forcing of glacier thinning on the mountains of equatorial East Africa
Authors: Hastenrath Stefan
Published: February 2009

Equatorial glaciers are particularly climate sensitive components of the environment and their area shrinkage is spectacular, but the quantitative appraisal of climatic forcing requires information on net balance and changing ice thickness. Unique in the tropical belt, observations of mass budget and surface topography have been gathered by decades‐long monitoring on Mount Kenya, particularly its largest, the Lewis Glacier. More limited information on ice thickness change is available for the summit of Kilimanjaro. Sensitivity analyses with constant precipitation, net allwave radiation and relative humidity serve to explore the sensible and latent heat transfer processes; humidity change riding on that of temperature providing the more substantial energy contribution to ablation. For Lewis Glacier it is found that with air some 0.7 °C cooler the mass budget could reach equilibrium. Observations on the secular evolution of air temperature and humidity in the areas of Mount Kenya and Rwenzori show compatible magnitudes, although contribution by radiative forcing cannot be excluded. For the summit of Kilimanjaro, above the mean freezing level, where ablation is limited to sublimation, turbulent heat transfer processes associated with temperature differences cannot account for the imbalance of the mass budget, and solar radiation forcing continues to be important for both the ice thinning and the lateral retreat of ice cliffs. Copyright © 2009 Royal Meteorological Society