bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pregnant students in the gross anatomy laboratory: Policies and practices at chiropractic colleges
Authors: Duray Stephen M. , Mekow Craig L. 
Published: January 2011

AbstractChiropractic and medical colleges have experienced a significant increase in the number of female applicants in recent years, a percentage of whom are pregnant or become pregnant following admission. It is therefore important to ask the question: How do institutions that educate future health care providers address the issue of pregnancy and the gross anatomy laboratory? A survey instrument was developed and pretested. IRB approval was obtained. The administrators charged with overseeing the policies and practices for the gross anatomy laboratory at each of the 16 chiropractic colleges in the USA were identified and contacted. An email containing a link to the Web based survey was sent to each, using SurveyMonkey. The survey response rate was 100%. A majority of colleges (69%) have a written policy regarding pregnancy and the gross laboratory. Of these, 36% allow pregnant students to take the laboratory if a waiver is signed, 18% do not allow them to take the laboratory, 18% allow them to take it without a waiver, and 27% have other policies. In cases where students do not take the gross laboratory while pregnant, 64% of colleges require them to take the laboratory after completion of their pregnancy, 27% require them to complete an alternative (dry) laboratory, and 9% have other policies. Considerable diversity exists in the way colleges address this issue. It is at present unknown whether pregnant students or their fetuses are at any risk from laboratory chemicals. Risk assessment research is needed before consistent policies can be developed. Anat Sci Educ. © 2011 American Association of Anatomists.
Oxazolones in Organocatalysis, New Tricks for an Old Reagent
Authors: Alba Andrea‐Nekane R. , Rios Ramon 
Published: January 2011

AbstractOxazolones or azlactones are among the most‐common starting materials for the synthesis of quaternary amino acids. Since the seminal works of Steglich and co‐workers until the recent examples from Ooi and co‐workers, azlactones have been the focus of intense research. Oxazolones are also widely used in organometallic chemistry; however, with the “renaissance” of organocatalysis, this reagent has emerged as an important starting material for a broad range of new organocatalytic asymmetric methodologies. In this Focus Review, we aim to cover all of these new organocatalytic methodologies. We begin by discussing the dynamic kinetic resolution reactions developed with azlactones. Then, we disclose the organocatalytic rearrangements. Finally, we focus on the use of oxazolones as nucleophiles in organocatalytic processes.
Gold Behaves as Hydrogen in the Intermolecular Self‐Interaction of Metal Aurides MAu4 (M=Ti, Zr, and Hf)
Authors: Jung Jaehoon , Kim Hyemi , Kim Jong Chan , Park Min Hee , Han Young‐Kyu 
Published: January 2011

AbstractWe performed density functional calculations to examine the intermolecular self‐interaction of metal tetraauride MAu4 (M=Ti, Zr, and Hf) clusters. We found that the metal auride clusters have strong dimeric interactions (2.8–3.1 eV) and are similar to the metal hydride analogues with respect to structure and bonding nature. Similarly to (MH4)2, the (μ‐Au)3 Cs structures with three three‐center two‐electron (3c–2e) bonds were found to be the most stable. Natural orbital analysis showed that greater than 96 % of the Au 6s orbital contributes to the 3c–2e bonds, and this predominant s orbital is responsible for the similarity between metal aurides and metal hydrides (>99 % H 1s). The favorable orbital interaction between occupied Au 6s and unoccupied metal d orbitals leads to a stronger dimeric interaction for MAu4‐MAu4 than the interaction for MH4‐MH4. There is a strong relationship between the dimeric interaction energy and the chemical hardness of its monomer for (MAu4)2 and (MH4)2.
Flux coupling and transcriptional regulation within the metabolic network of the photosynthetic bacterium Synechocystis sp. PCC6803
Authors: Montagud Arnau , Zelezniak Aleksej , Navarro Emilio , de Córdoba Pedro Fernández , Urchueguía Javier F. , Patil Kiran Raosaheb 
Published: January 2011

AbstractSynechocystis sp. PCC6803 is a model cyanobacterium capable of producing biofuels with CO2 as carbon source and with its metabolism fueled by light, for which it stands as a potential production platform of socio‐economic importance. Compilation and characterization of Synechocystis genome‐scale metabolic model is a pre‐requisite toward achieving a proficient photosynthetic cell factory. To this end, we report iSyn811, an upgraded genome‐scale metabolic model of Synechocystis sp. PCC6803 consisting of 956 reactions and accounting for 811 genes. To gain insights into the interplay between flux activities and metabolic physiology, flux coupling analysis was performed for iSyn811 under four different growth conditions, viz., autotrophy, mixotrophy, heterotrophy, and light‐activated heterotrophy (LH). Initial steps of carbon acquisition and catabolism formed the versatile center of the flux coupling networks, surrounded by a stable core of pathways leading to biomass building blocks. This analysis identified potential bottlenecks for hydrogen and ethanol production. Integration of transcriptomic data with the Synechocystis flux coupling networks lead to identification of reporter flux coupling pairs and reporter flux coupling groups – regulatory hot spots during metabolic shifts triggered by the availability of light. Overall, flux coupling analysis provided insight into the structural organization of Synechocystis sp. PCC6803 metabolic network toward designing of a photosynthesis‐based production platform.
A Novel Organometallic ReI Complex with Favourable Properties for Bioimaging and Applicability in Solid‐Phase Peptide Synthesis
Authors: Raszeja Lukasz , Maghnouj Abdelouahid , Hahn Stephan , Metzler‐Nolte Nils 
Published: January 2011

AbstractOrganometallic complexes possess great potential for imaging applications in biology, due to their kinetic stability and often favourable intrinsic properties. In this work we present a new class of ReI‐tricarbonyl complexes with a substituted bis(phenanthridinylmethyl)amine (bpm) ligand. The complex Re(CO)3(R‐bpm) could be conveniently prepared by microwave synthesis from [Re(CO)3(H2O)3]Br and a suitably substituted bis(phenanthridinylmethyl)amine (R‐bpm). Complex 5, with R=CH2‐CO2‐CH3, was characterized by a single‐crystal X‐ray structure. Complex 6 (R=CH2‐C6H4‐CO2H) was used in solid‐phase peptide synthesis (SPPS) to label the neurotensin(8–13) (NT) fragment N‐terminally. The complexes show luminescence emission with large Stokes shifts (λex=350 nm, λem=570 nm). Cellular uptake and intracellular localization studies in several cell lines demonstrate the utility of the new Re(CO)3(R‐bpm) complexes for fluorescence imaging and reveal significant differences between the simple methyl ester 5 and the NT bioconjugate 7.
Validation of the seventh edition of the American Joint Committee on Cancer TNM staging system for gastric cancer
Authors: Jung Hun , Lee Han Hong , Song Kyo Young , Jeon Hae Myung , Park Cho Hyun 
Published: January 2011

AbstractBACKGROUND:The seventh edition of the American Joint Committee on Cancer (AJCC) TNM classification for gastric cancer was published in 2010 and included major revisions. The aim of the current study was to evaluate the validity of the seventh edition TNM classification for gastric cancer based on an Asian population.METHODS:A total of 2916 gastric cancer patients who underwent R0 surgical resection from 1989 through 2008 in a single institute were included, and were analyzed according to the seventh edition of the TNM classification for validation.RESULTS:When adjusted using the seventh edition of the TNM classification, upstaging was observed in 771 patients (26.4%) and downstaging was observed in 178 patients (6.1%) compared with the sixth edition of the TNM classification. The relative risk (RR) of seventh edition pT classification was found to be increased with regular intensity compared with the sixth edition pT classification. The RR of seventh edition pN classification was found to be increased with irregular intensity compared with the sixth edition pN classification. In survival analysis, there were significant differences noted for each stage of disease, but only a marginal difference was demonstrated between stage IA and stage IB (P = .049). In the hybrid TNM classification, which combines the seventh edition pT classification and the sixth edition pN classification, both pT and pN classifications demonstrated a more ideal distribution of the RR, and 5‐year survival rates also showed a significant difference for each stage (P
<.01).CONCLUSIONS:The seventh edition of the TNM classification was considered valid based on the results of the current study. However, the hybrid TNM classification, comprised of a combination of the seventh edition pT classification and sixth edition pN classification, should be considered for the next edition. Cancer 2011. © 2011 American Cancer Society.
A novel automated assay for the rapid identification of metastatic breast carcinoma in sentinel lymph nodes
Authors: Feldman Sheldon , Krishnamurthy Savitri , Gillanders William , Gittleman Mark , Beitsch Peter D. , Young Peter R. , Streck Christian J. , Whitworth Pat W. , Levine Edward A. , Boolbol Susan , Han Linda K. , Hermann Robert , Hoon Dave S. B. , Giuliano Armando E. , Meric‐Bernstam Funda ,   for the US One Step Nucleic Acid Amplification Clinical Study Group
Published: January 2011

AbstractBACKGROUND:The authors prospectively evaluated the performance of a proprietary molecular testing platform using one‐step nucleic acid amplification (OSNA) for the detection of metastatic carcinoma in sentinel lymph nodes (SLNs) in a large multicenter trial and compared the OSNA results with the results from a detailed postoperative histopathologic evaluation (reference pathology) and from intraoperative imprint cytology (IC).METHODS:In total, 1044 SLN samples from 496 patients at 11 clinical sites were analyzed. Alternate 1‐mm sections were subjected to either detailed histopathologic evaluation with hematoxylin and eosin and pancytokeratin immunostaining or the OSNA Breast Cancer System, which was calibrated to detect tumor deposits >0.2 mm by measuring cytokeratin 19 messenger RNA. At 7 sites, IC was performed before permanent section. The OSNA results were classified as negative (<250 copies/μL), micrometastases (from ≥250 to <5000 copies/μL), or macrometastases (≥5000 copies/μL).RESULTS:The sensitivity and specificity of the OSNA breast cancer system compared with reference pathology were 77.5% (95% confidence interval, 69.7%‐84.2%) and 95.8% (95% confidence interval, 94.3%‐97.0%), respectively, before discordant case analyses (DCA). Sensitivity and specificity after DCA were 82.7% and 97.7%, and final concordance was 95.8%. Performance for invasive lobular carcinoma demonstrated 88.2% sensitivity (95% confidence interval, 63.6%‐98.5%) and 98.5% specificity (95% confidence interval, 92%‐100%). The sensitivity of OSNA was significantly better than that of IC (80% vs 63%; P = .0229).CONCLUSIONS:The OSNA breast cancer system proved to be highly accurate for the detection of metastatic breast cancer in axillary SLNs. Sensitivity was comparable to that predicted for conventional postoperative histologic examination at 2‐mm intervals and was significantly more sensitive than IC. Automation, semiquantitative results enabling the differentiation of macrometastasis and micrometastasis, and rapid results render the assay suitable for intraoperative and/or permanent evaluation of SLNs. Cancer 2011. © 2011 American Cancer Society.
GABAergic and glutamatergic identities of developing midbrain Pitx2 neurons
Authors: Waite M.R. , Skidmore J.M. , Billi A.C. , Martin J.F. , Martin D.M. 
Published: January 2011

AbstractPitx2, a paired‐like homeodomain transcription factor, is expressed in post‐mitotic neurons within highly restricted domains of the embryonic mouse brain. Previous reports identified critical roles for PITX2 in histogenesis of the hypothalamus and midbrain, but the cellular identities of PITX2‐positive neurons in these regions were not fully explored. This study characterizes Pitx2 expression with respect to midbrain transcription factor and neurotransmitter phenotypes in mid‐to‐late mouse gestation. In the dorsal midbrain, we identified Pitx2‐positive neurons in the stratum griseum intermedium (SGI) as GABAergic and observed a requirement for PITX2 in GABAergic differentiation. We also identified two Pitx2‐positive neuronal populations in the ventral midbrain, the red nucleus, and a ventromedial population, both of which contain glutamatergic precursors. Our data suggest that PITX2 is present in regionally restricted subpopulations of midbrain neurons and may have unique functions that promote GABAergic and glutamatergic differentiation. Developmental Dynamics 240:333–346, 2011. © 2011 Wiley‐Liss, Inc.
cis‐regulatory mutations are a genetic cause of human limb malformations
Authors: VanderMeer Julia E. , Ahituv Nadav 
Published: January 2011

AbstractThe underlying mutations that cause human limb malformations are often difficult to determine, particularly for limb malformations that occur as isolated traits. Evidence from a variety of studies shows that cis‐regulatory mutations, specifically in enhancers, can lead to some of these isolated limb malformations. Here, we provide a review of human limb malformations that have been shown to be caused by enhancer mutations and propose that cis‐regulatory mutations will continue to be identified as the cause of additional human malformations as our understanding of regulatory sequences improves. Developmental Dynamics 240:920–930, 2011. © 2011 Wiley‐Liss, Inc.
Facile Preparation of Paramagnetic RuIII and OsIII Hexacyanides
Authors: Vostrikova Kira E. , Peresypkina Eugenia V. 
Published: January 2011

AbstractDiamagnetic K4[M(CN)6], M = RuII, OsII are easily and quantitatively transformed into paramagnetic [M(CN)6]3– in methanol with the help of crown ethers. Hexacyanoosmate(II) is oxidized by air, whereas for hexacyanoruthenate(II), H2O2 is needed. These two cyanometallates, (K@18‐crown‐6)3[M(CN)6]·nSolv, were characterized both in solution and in the solid state. The compounds were obtained as single crystals, and their crystal and molecular structures were determined by X‐ray diffraction analysis. In the proposed synthetic method, the use of methanol minimizes hydrolysis and considerably increases the yield and purity.
Diiron Complexes with Pendant Phenol Group(s) as Mimics of the Diiron Subunit of [FeFe]‐Hydrogenase: Synthesis, Characterisation, and Electrochemical Investigation
Authors: Tang Ying , Wei Zhenhong , Zhong Wei , Liu Xiaoming 
Published: January 2011

AbstractFour diiron hexacarbonyl complexes, [Fe2(μ‐SCH2‐o‐C6H4OMe)2(CO)6] (4a), [Fe2{μ‐SCH2‐o,m‐C6H3(OMe)2}2(CO)6] (4b), [Fe2{μ‐SCH2‐o,o′‐C6H3(CO2Me)(OMe)}2(CO)6] (4c) and the demethylated form of complex 4a, [Fe2(μ‐SCH2‐o‐C6H4OH)2(CO)6] (5a), were synthesised and fully characterised. Complexes 4b and 4c were also structurally analysed. Electrochemical investigations revealed that the integrity of the bridging linkages of the examined diiron complexes significantly affect their reduction reversibility and catalysis through a coupled chemical reaction in a unique ECE mechanism, widely adopted by complexes with the core {Fe2(CO)4–6}. Demethylation of complexes 4a and 1Me, [Fe2(μ‐SCH2)2CMe(CH2‐o‐C6H4OMe)(CO)6], by BBr3 led to complexes (5a and 1H, [Fe2(μ‐SCH2)2CMe(CH2‐o‐C6H4OH)(CO)6]) with pendant phenol group(s), a weak acid. Deprotonation of the two complexes produced the pendant phenolate, which instantly intramolecularly substitutes the bound CO to yield species of the coordination form FeI–OR (R = phenolic moiety). Electrochemical investigation revealed that the pendant phenol groups in complexes 1H and 5a do not seem to improve their catalytic efficiency in proton reduction in the medium acetic acid/dichloromethane.
On the Compatibility of Azides in Phosphoramidite‐Based Couplings: Synthesis of a Novel, Convertible Azido‐Functionalized CyPLOS Analogue
Authors: Coppola Cinzia , Simeone Luca , De Napoli Lorenzo , Montesarchio Daniela 
Published: January 2011

AbstractWith the aim of preparing a library of ion transporters based on a CyPLOS (cyclic phosphate‐linked oligosaccharide) backbone, we describe the synthesis of a novel azido‐derivatized CyPLOS analogue that is tailored for practical post‐synthetic functionalization with a variety of labels. As a prerequisite for the effective preparation of this phosphate‐linked macrocycle, the compatibility of azido alcohols as coupling agents in phosphoramidite synthetic protocols was preliminarily investigated in solution by using 31P NMR spectroscopy to monitor the standard coupling of a nucleoside 3′‐phosphoramidite with suitable model alcohols and azides.
Highly Enantioselective Access to α‐Dibenzylamino Ketones from Chiral Nonracemic α‐Bromo α′‐Sulfinyl Ketones by Dynamic Kinetic Resolution: Synthesis of (2R,1′S)‐2‐[1‐(Dibenzylamino)alkyl]oxiranes
Authors: Géant Pierre‐Yves , Martínez Jean , Salom‐Roig Xavier J. 
Published: January 2011

AbstractA novel and efficient synthesis of enantiomerically pure α‐dibenzylamino α′‐sulfinyl ketones starting from a mixture of both epimers of α‐bromo α′‐(R)‐sulfinyl ketone has been realized through combined in situ substitution–epimerization in a so‐called Dynamic Kinetic Resolution (DKR). The scope of the reaction has been examined, and four differently substituted α‐(S)‐dibenzylamino α′‐(R)‐sulfinyl ketones were obtained in good yields with excellent diastereoselectivities. The utility of these derivatives was further illustrated with a highly stereoselective synthesis of syn‐(2R,1′S)‐2‐(1‐dibenzylaminoalkyl)oxiranes.
Indium‐Mediated Allenylation of Aldehydes and Its Application in Carbohydrate Chemistry: Efficient Synthesis of D‐Ribulose and 1‐Deoxy‐D‐ribulose
Authors: Fischer Michael , Schmölzer Christoph , Nowikow Christina , Schmid Walther 
Published: January 2011

AbstractA two‐step reaction sequence starting with the indium‐mediated allenylation of aldehydes with 4‐bromo‐2‐butyn‐1‐ols and subsequent ozonolysis of the resulting allenylic product was developed to generate a variety of dihydroxyacetone derivatives. The regioselectivity of the indium‐promoted C–C bond‐forming reaction can be manipulated through hydroxy protecting groups on 4‐bromo‐2‐butyn‐1‐ol, yielding either allenes or alkynes as preferred products. Compared to established protocols, the necessary amount of indium for this type of allenylation can be decreased by a factor of two to four. The versatility of this strategy was demonstrated in thestereoselective and straightforward synthesis of D‐ribulose and 1‐deoxy‐D‐ribulose.
Synthesis of Biologically Active Nonnatural Palmarumycin Derivatives
Authors: Aslan Abdulselam , Altun Sultan , Ahmed Ishtiaq , Flörke Ulrich , Schulz Barbara , Krohn Karsten 
Published: January 2011

AbstractDiels–Alder reaction of benzoquinone monoacetal 1 with 1‐methoxy‐1,3‐butadiene (4) and dimethyl(1‐methyl‐3‐vinylcyclohex‐3‐enyl)(phenyl)silane (5) gave the expected adducts 2 and 3, whereas with siloxy‐dienes such as 3‐methyl‐1‐(trimethylsiloxy)‐1,3‐butadiene (6) a 1,2‐aldol‐type adduct 9 was isolated. The Diels–Alder adduct 2 was isomerized under mild basic conditions to the olefin 10 and eliminated to the diene 11 under mild acidic or thermal conditions. The olefins 2, 10 and 11 were subjected to epoxidation with m‐chloroperbenzoic acid and tert‐butyl hydroperoxide under mild basic conditions to afford the epoxides 12, 15, and 18 under the former conditions and 13, 14, 16, 17, 19, and 20 under the latter conditions. The olefins 1, 2, 10, 11, and 20 were also transformed into the respective cis‐diols 21a and 23a–26a. From theses diols the corresponding diacetates (b) andacetonides (c) were prepared. The compounds were tested against the Gram‐negative bacterium Escherichia coli, the Gram‐positive bacterium Bacillus megaterium, and the fungus Microbotryum violaceum. Whereas compound 25b was the most active of the diacetates and the epoxide 18 the most active of all substances, all of the compounds were biologically active against the three test organisms, equalling and surpassing those of the natural palmarumycins.
Analysis of inorganic cations in biological samples by the combination of micro‐electrodialysis and capillary electrophoresis with capacitively coupled contactless conductivity detection
Authors: Doan Thi Kieu Oanh , Kubáň Pavel , Kubáň Petr , Kiplagat Isaac K. , Boček Petr 
Published: January 2011

AbstractMicro‐electrodialysis (μED) and CE were combined for rapid pretreatment and subsequent determination of inorganic cations in biological samples. Combination of μED with CE greatly improved the analytical performance of the latter as the adsorption of high molecular weight compounds present in real samples on the inner capillary wall was eliminated. Fifty microliter of 80‐fold diluted human body fluids such as plasma, serum and whole blood was used in the donor compartment of the μED system requiring less than 1 μL of the original body fluid per analysis. Inorganic cations that migrated through a cellulose acetate dialysis membrane with molecular weight cut‐off value of 500 Da were collected in the acceptor solution and were then analyzed using CE‐C4D. Baseline separation of inorganic cations was achieved in a BGE solution consisting of 12.5 mM maleic acid, 15 mM L‐arginine and 3 mM 18‐crown‐6 at pH 5.5. Repeatability of the CE‐C4D method was better than 0.5% and 2.5% for migration times and peak areas, respectively; limits of detection of all inorganic cations in the presence of 2 mM excess of Na+ were around 1 μM and calibration curves were linear with correlation coefficients better than 0.998. Repeatability of the sample pretreatment procedure was calculated for six independent electrodialysis runs of artificial and real samples and was better than 11.8%. Recovery values between 96.3 and 110% were achieved for optimized electrodialysis conditions of standard solutions and real samples; lifetime of the dialysis membranes for pretreatment of real samples was estimated to 100 runs.