bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design Principles and Theory of Paramagnetic Fluorine‐Labelled Lanthanide Complexes as Probes for 19F Magnetic Resonance: A Proof‐of‐Concept Study
Authors: Chalmers Kirsten H. , De Luca Elena , Hogg Naomi H. M. , Kenwright Alan M. , Kuprov Ilya , Parker David , Botta Mauro , Wilson J. Ian , Blamire Andrew M. 
Published: December 2009

AbstractThe synthesis and spectroscopic properties of a series of CF3‐labelled lanthanide(III) complexes (Ln=Gd, Tb, Dy, Ho, Er, Tm) with amide‐substituted ligands based on 1,4,7,10‐tetraazacyclododecane are described. The theoretical contributions of the 19F magnetic relaxation processes in these systems are critically assessed and selected volumetric plots are presented. These plots allow an accurate estimation of the increase in the rates of longitudinal and transverse relaxation as a function of the distance between the LnIII ion and the fluorine nucleus, the applied magnetic field, and the re‐rotational correlation time of the complex, for a given LnIII ion. Selected complexes exhibit pH‐dependent chemical shift behaviour, and a pKa of 7.0 was determined in one example based on the holmium complex of an ortho‐cyano DO3A‐monoamide ligand, which allowed the pH to be assessed by measuring the difference in chemical shift (varying by over 14 ppm) between two 19F resonances. Relaxation analyses of variable‐temperature and variable‐field 19F, 17O and 1H NMR spectroscopy experiments are reported, aided by identification of salient low‐energy conformers by using density functional theory. The study of fluorine relaxation rates, over a field range of 4.7 to 16.5 T allowed precise computation of the distance between the LnIII ion and the CF3 reporter group by using global fitting methods. The sensitivity benefits of using such paramagnetic fluorinated probes in 19F NMR spectroscopic studies are quantified in preliminary spectroscopic and imaging experiments with respect to a diamagnetic yttrium(III) analogue.
SN2’ versus SN2 Reactivity: Control of Regioselectivity in Conversions of Baylis–Hillman Adducts
Authors: Baidya Mahiuddin , Remennikov Grygoriy Y. , Mayer Peter , Mayr Herbert 
Published: December 2009

AbstractTiCl4‐induced Baylis–Hillman reactions of α,β‐unsaturated carbonyl compounds with aldehydes yield the (Z)‐2‐(chloromethyl)vinyl carbonyl compounds 5, which react with 1,4‐diazabicyclo[2.2.2]octane (DABCO), quinuclidine, and pyridines to give the allylammonium ions 6. Their combination with less than one equivalent of the potassium salts of stabilized carbanions (e.g. malonate) yields methylene derivatives 8 under kinetically controlled conditions (SN2’ reactions). When more than one equivalent of the carbanions is used, a second SN2’ reaction converts 8 into their thermodynamically more stable allyl isomers 9. The second‐order rate constants for the reactions of 6 with carbanions have been determined photometrically in DMSO. With these rate constants and the previously reported nucleophile‐specific parameters N and s for the stabilized carbanions, the correlation log k (20 °C)=s(N + E) allowed us to calculate the electrophilicity parameters E for the allylammonium ions 6 (−19<E <−18). The kinetic data indicate the SN2’ reactions to proceed via an addition–elimination mechanism with a rate‐determining addition step.
Chlamydomonas mutants display reversible deficiencies in flagellar beating and axonemal assembly
Authors: Wei Mei , Sivadas Priyanka , Owen Heather A. , Mitchell David R. , Yang Pinfen 
Published: December 2009

AbstractAxonemal complexes in flagella are largely prepackaged in the cell body. As such, one mutation often results in the absence of the co‐assembled components and permanent motility deficiencies. For example, a Chlamydomonas mutant defective in RSP4 in the radial spoke (RS), which is critical for bend propagation, has paralyzed flagella that also lack the paralogue RSP6 and three additional RS proteins. Intriguingly, recent studies showed that several mutant strains contain a mixed population of swimmers and paralyzed cells despite their identical genetic background. Here we report a cause underlying these variations. Two new mutants lacking RSP6 swim processively and other components appear normally assembled in early log phase indicating that, unlike RSP4, this paralogue is dispensable. However, swimmers cannot maintain the typical helical trajectory and reactivated cell models tend to spin. Interestingly the motile fraction and the spokehead content dwindle during stationary phase. These results suggest that (1) intact RS is critical for maintaining the rhythm of oscillatory beating and thus the helical trajectory; (2) assembly of the axonemal complex with subtle defects is less efficient and the inefficiency is accentuated in compromised conditions, leading to reversible dyskinesia. Consistently, several organisms only possess one RSP4/6 gene. Gene duplication in Chlamydomonas enhances RS assembly to maintain optimal motility in various environments. © 2009 Wiley‐Liss, Inc.
Changes in plasma membrane structure and electromotile properties in prestin deficient outer hair cells
Authors: He David Z.Z. , Jia Shuping , Sato Takashi , Zuo Jian , Andrade Leonardo R. , Riordan Gavin P. , Kachar Bechara 
Published: December 2009

AbstractCochlear outer hair cells (OHCs) rapidly change their length and stiffness when their membrane potential is altered. Prestin, the motor protein for this electromotility, is present along the OHC lateral plasma membrane where there is a high density of intra‐membrane protein particles (IMPs). However, it is not known to what extent prestin contributes to this unusual dense population of proteins and overall organization of the membrane to generate the unique electromechanical response of OHCs. We investigated the relationship of prestin with the IMPs, the underlying cortical cytoskeletal lattice, and electromotility in prestin‐deficient mice. Using freeze‐fracture, we observed a reduction in density and size of the IMPs that correlates with the reduction and absence of prestin in the heterozygous and homozygous mice, respectively. We also observed a reduction or absence of electromotility‐related charge density, axial stiffness, and piezoelectric properties of the OHC. A comparison of the charge density with the number of IMPs suggests that prestin forms tetramers in the wild type but is likely to form lower number oligomers in the prestin‐deficient OHCs from the heterozygous mice. Interestingly, the characteristic actin‐based cortical cytoskeletal lattice that underlies the membrane is absent in the prestin‐null OHCs, suggesting that prestin is also required for recruiting or maintaining the cortical cytoskeletal lattice. These results suggest that the majority of the IMPs are indeed prestin and that electrically evoked length and stiffness changes are interrelated and dependent on both prestin and on the cortical actin cytoskeletal lattice of the OHC lateral membrane. Published 2009 Wiley‐Liss, Inc.
Modulation on C‐ and N‐Terminal Moieties of a Series of Potent and Selective Linear Tachykinin NK2 Receptor Antagonists
Authors: Gensini Martina , Altamura Maria , Dimoulas Tula , Fedi Valentina , Giannotti Danilo , Giuliani Sandro , Guidi Antonio , Harmat Nicholas J. S. , Meini Stefania , Nannicini Rossano , Pasqui Franco , Tramontana Manuela , Triolo Antonio , Maggi Carlo Alberto 
Published: December 2009

AbstractHerein we describe the synthesis of a series of new potent tachykinin NK2 receptor antagonists by the modulation of the C‐ and N‐terminal moieties of ibodutant (MEN 15596, 1). The N‐terminal benzo[b]thiophene ring was replaced by different substituted naphthalenes and benzofurans, while further modifications were evaluated at the C‐terminal tetrahydropyran moiety. Most compounds demonstrated a high affinity for the human NK2 receptor and high in vitro antagonist potency, indicating that a wide range of substituents at both termini can be incorporated in the molecule without detrimental effects on the interactions with the NK2 receptor. Selected compounds were tested in vivo confirming their activity as NK2 antagonists. In particular, after both iv and id administration to guinea pig, compound 61 b was able to antagonize NK2‐induced colonic contractions with a potency and duration‐of‐action fully comparable to the reference compound 1 (MEN 15596, ibodutant).
Intensive chemotherapy improves survival in pediatric high‐grade glioma after gross total resection: results of the HIT‐GBM‐C protocol
Authors: Wolff Johannes E.A. , Driever Pablo Hernaiz , Erdlenbruch Bernhard , Kortmann Rolf D. , Rutkowski Stefan , Pietsch Torsten , Parker Crystal , Metz Monica Warmuth , Gnekow Astrid , Kramm Christof M. 
Published: December 2009

AbstractBACKGROUND:The authors hypothesized that intensified chemotherapy in protocol HIT‐GBM‐C would increase survival of pediatric patients with high‐grade glioma (HGG) and diffuse intrinsic pontine glioma (DIPG).METHODS:Pediatric patients with newly diagnosed HGG and DIPG were treated with standard fractionated radiation and simultaneous chemotherapy (cisplatin 20 mg/m2 × 5 days, etoposide 100 mg/m2 × 3 days, and vincristine, and 1 cycle of cisplatin + etoposide + ifosfamide 1.5 g/m × 5 days [PEI] during the last week of radiation). Subsequent maintenance chemotherapy included further cycles of PEI in Weeks 10, 14, 18, 22, 26, and 30, followed by oral valproic acid.RESULTS:Ninety‐seven (pons, 37; nonpons, 60) patients (median age, 10 years; grade IV histology, 35) were treated. Resection was complete in 21 patients, partial in 29, biopsy only in 26, and not performed in 21. Overall survival rates were 91% (standard error of the mean [SE] ± 3%), 56%, and 19% at 6, 12, and 60 months after diagnosis, respectively. When compared with previous protocols, there was no significant benefit for patients with residual tumor, but the 5‐year overall survival rate for patients with complete resection treated on HIT‐GBM‐C was 63% ± 12% SE, compared with 17% ± 10% SE for the historical control group (P = .003, log‐rank test).CONCLUSIONS:HIT‐GBM‐C chemotherapy after complete tumor resection was superior to previous protocols. Cancer 2010. © 2009 American Cancer Society.
Underutilization of radiotherapy for lung cancer in New South Wales, Australia
Authors: Vinod Shalini K. , Simonella Leonardo , Goldsbury David , Delaney Geoff P. , Armstrong Bruce , O'Connell Dianne L. 
Published: December 2009

AbstractBACKGROUND:Lung cancer is the leading cause of cancer death in most developed countries. Radiotherapy is important in its treatment, with an estimated optimal utilization rate between 45% and 68% at initial diagnosis. The objective of this study was to describe radiotherapy practice for lung cancer in New South Wales (NSW), Australia.METHODS:Patients with lung cancer were identified prospectively from the NSW Central Cancer Registry (CCR) from November 1, 2001 to December 31, 2002. Questionnaires were mailed to diagnosing and treating clinicians to obtain detailed information on diagnosis, staging, referrals, and treatment. The authors describe referral for and receipt of radiotherapy treatment.RESULTS:Of 1812 patients with lung cancer patients who were identified, 943 patients (52%) were referred for radiotherapy, 846 patients (47%) received a radiotherapy questionnaire, and 727 patients (40%) received radiotherapy. Compared with optimal radiotherapy, there was less curative radiotherapy to the primary site (20% actual vs 50% optimal), and there was more palliative radiotherapy to metastatic sites (36% actual vs 11% optimal). The greatest shortfall in radiotherapy use was observed in patients who had limited stage small cell lung cancer (46% actual vs 94% optimal). The use of combined‐modality treatment for stage III nonsmall cell lung cancer and for limited stage small cell lung cancer was uncommon.CONCLUSIONS:There is underutilization of radiotherapy for lung cancer in NSW, especially in small cell lung cancer. The use of combined‐modality treatment for potentially curable lung cancers is suboptimal. These issues have to be addressed to improve survival and quality of life for patients with lung cancer. Cancer 2010. © 2009 American Cancer Society.
Distinct features of colorectal cancer in children and adolescents
Authors: Sultan Iyad , Rodriguez‐Galindo Carlos , El‐Taani Hani , Pastore Guido , Casanova Michela , Gallino Gianfranco , Ferrari Andrea 
Published: December 2009

AbstractBACKGROUND:Colorectal cancer is exceedingly rare in children and adolescents. Reports from small series indicate that poor prognostic factors are more common in children than in adults, resulting in worse outcome for the pediatric population.METHODS:The Surveillance, Epidemiology, and End Results database was searched for records of children/adolescents with colorectal cancer, and the features and outcomes were compared with those of adults.RESULTS:From January 1973 through December 2005, only 159 children/adolescents (ages 4‐20 years) were reported with a diagnosis of colorectal cancer. The most common sites of involvement were the rectum (27%) and the transverse colon (26%). Adenocarcinoma was the most common histiotype in both adults and pediatric patients; however, children/adolescents had more unfavorable histiotypes (ie, mucinous adenocarcinoma [22%] and signet ring cell carcinoma [18%]) when compared with adults (10% and 1%, respectively; P < .001). Poorly differentiated and undifferentiated tumors (grades III and IV, respectively) and distant stage were more common in children/adolescents (P < .001). The 5‐year relative survival estimates in children/adolescents and adults were 40% ± 4.2% and 60% ± 0.10%, respectively, confirming a worse outcome in the pediatric age group (P < .001).CONCLUSIONS:Children/adolescents represent a minority of patients with colorectal cancer and have high‐risk features and worse outcome than adults. The small number of patients in this age group was an impediment to the development of meaningful clinical trials. Thus, the principles of management for adult colorectal cancer should be used in the treatment of children and adolescents. Cancer 2010. © 2009 American Cancer Society.
Tris(2,4‐pentanedionato)scandium(III) as a Precursor for Plasma‐Assisted Liquid Injection CVD to Deposit Nanocrystalline Scandia Thin Films
Authors: Selvakumar Jayapragasam , Raghunathan Vinjamoor S. , Nagaraja Karachalacheruvu S. 
Published: December 2009

AbstractNanocrystalline cubic scandium oxide thin film deposition by plasma‐assisted (PA) liquid injection (LI) CVD is studied at 773 K in a N2/O2 plasma environment with a triglyme solution of tris(2,4‐pentanedionato)scandium(III) (Sc(acac)3) as the precursor. The vapor pressure of the precursor is measured by employing a horizontal, dual‐arm, single‐furnace, thermogravimetric analyzer as a transpiration apparatus. The standard enthalpy of sublimation (79 ± 1 kJ mol−1) of Sc(acac)3 was measured from the Clausius–Clapeyron plot [ln(pe/Pa)T versus 1/T]. A nanocrystalline film of Sc2O3 with the (222) plane as the dominant orientation is obtained on glass under a deposition pressure of 0.8–1.2 mbar.
CVD of Copper(I) Nitride
Authors: Fallberg Anna , Ottosson Mikael , Carlsson Jan‐Otto 
Published: December 2009

AbstractCopper(I) nitride (Cu3N) is deposited by CVD using copper(II) hexafluoroacetylacetonate (Cu(hfac)2), ammonia, and water as precursors. The influences of process parameters on growth rate, phase content, chemical composition and morphology are studied. The introduction of water is found to increase film growth rate on the SiO2 substrate. Films are deposited in the tem‐perature range 250–550 °C. Single‐phase Cu3N is obtained up to 400 °C. A phase mixture of Cu3N and Cu is obtained at 425 °C, while a temperature of 550 °C and above yields single‐phase Cu. X‐ray diffraction (XRD) confirms that Cu3N has the cubic, anti‐ReO3‐type structure; with a cell parameter in the range 3.805–3.816 Å. X‐ray photoelectron spectroscopy (XPS) verifies the Cu3N stoichiometry. The films are free from impurities (below the detection limit of 1%) at a large excess of ammonia. Scanning electron microscopy (SEM) shows facetted grains, with the faces becoming more well‐defined at higher temperatures.
“Naked” [Mn3O]7+ Triangles: The Effect of Auxiliary Ligands on Magnetic Exchange
Authors: Manolopoulou Efi , Stoumpos Constantinos C. , Siczek Milosz , Lis Tadeusz , Brechin Euan K. , Milios Constantinos J. 
Published: December 2009

AbstractThe reaction between Mn(ClO4)2·6H2O, Et‐saoH2 (Et‐saoH2 = 2‐hydroxypropiophenone oxime), NEt4OH and [Ni(pao)2(py)2] (paoH = 2‐pyridylaldoxime) in MeOH forms the complex [MnIII3O(Et‐sao)3(HCO2)(MeOH)5] (1) in good yields. The reaction of MnCl2·4H2O, Me‐saoH2 (Me‐saoH2 = 2‐hydroxyphenylethanone oxime), NEt4OH and dl‐valine in MeOH gives the complex [MnIII3O(Me‐sao)3(MeOH)5]Cl (2) in moderate yields. In both complexes the building block consists of a triangular {MnIII3O(R‐sao)3} unit (R = Et, Me for 1 and 2, respectively). In the case of 2, the [Mn3] unit can be considered “naked” as there is no capping ligand present, whereas in the case of 1 a formate ion is terminally bonded to one metal centre. DC magnetic susceptibility measurements for 1 and 2 reveal the presence of both ferromagnetic and antiferromagnetic intramolecular interactions, depending on the Mn–N–O–Mn torsion angles within each cluster, leading to a ground state S = 2 for both complexes. Rationalization of this result is attempted by structural comparison of previously reported triangular [Mn3] oximate complexes on the basis of “flat” and “twisted” torsion angles and the effect of the auxiliary ligands.
Reactions of the Bornyl and Fenchyl Grignard Reagent with Chlorophosphanes – Diastereoselectivity and Mechanistic Implications
Authors: Beckmann Jens , Schütrumpf Alexandra 
Published: December 2009

AbstractThe reactions of the bornyl and fenchyl Grignard reagent with the chlorophosphanes Ph2PCl, PCl3 and (Et2N)2PCl, respectively, were studied by multinuclear NMR spectroscopy. The diastereoselectivity was found to be independent of the diastereomeric composition of the bornyl andfenchyl Grignard reagent (e.g., the endo/exo ratio), but dependent on the chlorophosphanes used. The results are consistent with a reaction mechanism that involves SET processes and radical intermediates. No or little diastereoselectivity was observed for the reactions involving Ph2PCl and PCl3. The reactions of the bornyl and fenchyl Grignard reagent with (Et2N)2PCl provided bornylP(NEt2)2 (4a) and β‐fenchylP(NEt2)2 (10b) with high diastereoselectivity (of 92 % and 88 % de). The novel chiral phosphane oxides bornylPh2PO (2a), isobornylPh2PO (2b), α‐fenchylPh2PO (8a) and β‐fenchylPh2PO (8b), phosphinic acids bornylP(O)(H)(OH) (5a) and β‐fenchylP(O)(H)(OH) (11b) and phosphonic acids bornylP(O)(OH)2 (6a) and β‐fenchylP(O)(OH)2 (12b) were isolated as colorless crystals. The molecular structures of 2b, 8a, 8b, 6a and 12b were determined by X‐ray crystallography.
Solid‐Phase Reactive Chromatography (SPRC): A New Methodology for Wittig and Horner–Emmons Reactions on a Column under Microwave Irradiation
Authors: Dakdouki Saada C. , Villemin Didier , Bar Nathalie 
Published: December 2009

AbstractA new methodology named solid‐phase reactive chromatography (SPRC), which combines reaction, separation, and purification into a single unit for the preparation of small samples, is described. This method was illustrated in the synthesis of some natural bioactive compounds, namely, methoxylated analogues of resveratrol, alkylresorcinols, and 5‐aryl‐2,4‐pentadienoates, over a column of alumina‐KF under microwave irradiation by using the Wittig and Horner–Emmons reactions. This approach permitted the preparation of the target olefins with high purity and good to excellent yields in short reaction times.
Biodistribution of anti‐diabetic Zn(II) complexes in human serum and in vitro protein‐binding studies by means of CZE–ICP‐MS
Authors: Bytzek Anna K. , Enyedy Éva A. , Kiss Tamás , Keppler Bernhard K. , Hartinger Christian G. 
Published: December 2009

AbstractApplication of modern analytical technology for studying the fate of metallodrugs after administration to the blood is of utmost importance for drug development. Zn(II) compounds are under development as insulin‐enhancing drugs with potential use in the treatment of diabetes. In comparison to the well‐established vanadium compounds, especially the lower risk of adverse effects due to the essentiality of the element in biological processes is advantageous. Herein, CZE–ICP‐MS studies on the interaction of Zn(II)‐maltolato, ‐2‐picolinato and ‐2,6‐dipicolinato complexes with human serum proteins are discussed and modeling calculations were confirmed by experimental results. Studies with human serum reveal preference for HSA over other less abundant proteins and serum components.
Burning and dripping behaviors of polymers under the UL94 vertical burning test conditions
Authors: Wang Yong , Zhang Feng , Chen Xilei , Jin Yang , Zhang Jun 
Published: December 2009

AbstractAn experimental setup was constructed to record the real‐time mass data of eight pure polymers under the UL94 vertical burning test conditions. The experiments showed that the flame rises up to the clamp or the dripping occurs soon for the pure polymers. The mass burned before the flame reaching the clamp and the dripping occurrence only accounts for a small fraction of the original mass of the specimen, which differentiates the UL94 test from the cone calorimeter test. The mass loss rate of polymer specimens is in the magnitude order of 0.001–0.01 g/s. It was also found that the flame of thin specimens usually reaches the clamp sooner than that of thick specimens. Apart from the dripping behaviors found in large‐scale fires, it is found that the diameter of the first drop for the tested polymers is in the range of 2.0–10.0 mm. The mass of the first drop increases with the first dripping time. The first dripping time and the mass of the first drop increase with the thickness of the specimen, especially for polymers of large‐size dripping type. Copyright © 2009 John Wiley & Sons, Ltd.
Histochemical localization of secretion and composition of the essential oil in Melittis melissophyllum L. subsp. melissophyllum from Central Italy
Authors: Maggi Filippo , Papa Fabrizio , Cristalli Gloria , Sagratini Gianni , Vittori Sauro , Giuliani Claudia 
Published: December 2009

AbstractThe distribution and morphology of the secretory structures in Melittis melissophyllum L. subsp. melissophyllum (Lamiaceae) were studied for the first time by light and scanning electron microscopy. The indumentum of the vegetative and reproductive organs includes non‐glandular hairs and peltate (type A) and capitate (types B and C) glandular trichomes. Histochemical techniques enabled specific location of the site of essential oil accumulation in the type A peltate hairs. In order to confirm the occurrence of the 1‐octen‐3‐ol chemotype in central Italy, six populations growing in different places were analysed for the essential oil composition by GC–FID and GC–MS. In all populations, 1‐octen‐3‐ol was detected as the major volatile component, representing 56.3–70.6% of the total oils. To date, these percentages are the highest detected in a plant essential oil. Copyright © 2009 John Wiley & Sons, Ltd.
Are disaggregate data useful for factor analysis in forecasting French GDP?
Authors: Barhoumi Karim , Darné Olivier , Ferrara Laurent 
Published: December 2009

AbstractThis paper compares the GDP forecasting performance of alternative factor models based on monthly time series for the French economy. These models are based on static and dynamic principal components obtained using time and frequency domain methods. We question whether it is more appropriate to use aggregate or disaggregate data to extract the factors used in forecasting equations. The forecasting accuracy is evaluated for various forecast horizons considering both rolling and recursive schemes. We empirically show that static factors, estimated from a small database, lead to competitive results, especially for nowcasting. Copyright © 2009 John Wiley & Sons, Ltd.