bluuebunny/crossref_metadata_2025_split huggingface dataset:
Asymmetric Catalysis Mediated by the Ligand Sphere of Octahedral Chiral‐at‐Metal Complexes
Authors: Gong Lei , Chen Liang‐An , Meggers Eric 
Published: August 2014

AbstractDue to the relationship between structure and function in chemistry, access to novel chemical structures ultimately drives the discovery of novel chemical function. In this light, the formidable utility of the octahedral geometry of six‐coordinate metal complexes is founded in its stereochemical complexity combined with the ability to access chemical space that might be unavailable for purely organic compounds. In this Minireview we wish to draw attention to inert octahedral chiral‐at‐metal complexes as an emerging class of metal‐templated asymmetric “organocatalysts” which exploit the globular, rigid nature and stereochemical options of octahedral compounds and promise to provide new opportunities in the field of catalysis.
The Trapping of Phenyldiazenes in Cycloaddition Reactions
Authors: Fehler Stefanie K. , Pratsch Gerald , Heinrich Markus R. 
Published: August 2014

AbstractThe reactivity of phenyldiazenes was studied intensively in the late 1960s, but not much is known about their behavior under acidic conditions. Based on the formation of phenyldiazenes from phenylazocarboxylates, we herein describe how reactions of phenyldiazenes can be directed into ionic or radical pathways. Cycloaddition reactions with furans leading to pyridazinium salts represent the first examples for the direct trapping of phenyldiazenes with conservation of the NN moiety.
Brief Report: Lumbar Spinal Stenosis Is a Highly Genetic Condition Partly Mediated by Disc Degeneration
Authors: Battié Michele C. , Ortega‐Alonso Alfredo , Niemelainen Riikka , Gill Kevin , Levalahti Esko , Videman Tapio , Kaprio Jaakko 
Published: August 2014

ObjectiveLumbar spinal stenosis is one of the most commonly diagnosed spinal disorders in older adults. Although the pathophysiology of the clinical syndrome is not well understood, a narrow central canal or intervertebral foramen is an essential or defining feature. The aim of the present study was to estimate the magnitude of genetic versus environmental influences on central lumbar spinal stenosis and to investigate disc degeneration and stature or bone development as possible genetic pathways.MethodsA classic twin study with multivariate analyses considering lumbar level and other covariates was conducted. The study sample comprised 598 male twins (147 monozygotic and 152 dizygotic pairs), 35–70 years of age, from the population‐based Finnish Twin Cohort. The primary phenotypes were central lumbar stenosis as assessed qualitatively on magnetic resonance imaging (MRI) and quantitatively measured dural sac cross‐sectional area. Additional phenotypes (to examine possible genetic pathways) included disc bulging and standing height, as an indicator of overall skeletal size or development.ResultsThe heritability estimate (h2) for qualitatively assessed central lumbar spinal stenosis on MRI was 66.9% (95% confidence interval [95% CI] 56.8, 74.5). The broad‐sense heritability estimate for dural sac cross‐sectional area was 81.2% (95% CI 74.5, 86.1), with a similar magnitude of genetic influences across lumbar levels (h2 = 72.4–75.6). The additive genetic correlation of quantitatively assessed stenosis and disc bulging was extremely high. There was no indication of shared genetic influences between stenosis and stature.ConclusionCentral lumbar spinal stenosis and associated dural sac dimensions are highly genetic, and disc degeneration (bulging) appears to be one pathway through which genes influence spinal stenosis.
Repositioning the Substrate Activity Screening (SAS) Approach as a Fragment‐Based Method for Identification of Weak Binders
Authors: Gladysz Rafaela , Cleenewerck Matthias , Joossens Jurgen , Lambeir Anne‐Marie , Augustyns Koen , Van der Veken Pieter 
Published: August 2014

AbstractFragment‐based drug discovery (FBDD) has evolved into an established approach for “hit” identification. Typically, most applications of FBDD depend on specialised cost‐ and time‐intensive biophysical techniques. The substrate activity screening (SAS) approach has been proposed as a relatively cheap and straightforward alternative for identification of fragments for enzyme inhibitors. We have investigated SAS for the discovery of inhibitors of oncology target urokinase (uPA). Although our results support the key hypotheses of SAS, we also encountered a number of unreported limitations. In response, we propose an efficient modified methodology: “MSAS” (modified substrate activity screening). MSAS circumvents the limitations of SAS and broadens its scope by providing additional fragments and more coherent SAR data. As well as presenting and validating MSAS, this study expands existing SAR knowledge for the S1 pocket of uPA and reports new reversible and irreversible uPA inhibitor scaffolds.
Synthesis of Chiral α‐Benzyl‐β2‐hydroxy Carboxylic Acids through Iridium‐Catalyzed Asymmetric Hydrogenation of α‐Oxymethylcinnamic Acids
Authors: Li Ze‐Yu , Song Song , Zhu Shou‐Fei , Guo Na , Wang Li‐Xin , Zhou Qi‐Lin 
Published: August 2014

AbstractAn asymmetric hydrogenation of α‐oxymethylcinnamic acids was developed by using chiral spiro phosphine‐oxazoline/iridium complexes as catalysts to prepare β2‐hydroxycarboxylic acids with high reactivity (TON up to 2000) and excellent enantioselectivity (up to 99.5% ee). By using this highly efficient asymmetric hydrogenation as a key step, a concise total synthesis of natural product homoisoflavone (S)‐(+)‐4 was accomplished.
N‐Heterocyclic Carbene‐catalyzed Reactions of o‐Aminonitriles with Carbonyl Compounds Approach to 2,3‐Dihydroquinazolin‐4(1H)‐ones
Authors: Chai Hongxin , Li Jiarong , Yang Liupan , Liu Mingxing , Yang Deli , Zhang Qi , Shi Daxin 
Published: August 2014

AbstractA green, efficient and convenient N‐heterocyclic carbene‐catalyzed procedure for the synthesis of novel 2,3‐dihydroquinazolin‐4(1H)‐one derivates via condensation of o‐aminonitriles and various carbonyl compounds was described.
KRAS mutation influences recurrence patterns in patients undergoing hepatic resection of colorectal metastases
Authors: Kemeny Nancy E. , Chou Joanne F. , Capanu Marinela , Gewirtz Alexandra N. , Cercek Andrea , Kingham T. Peter , Jarnagin William R. , Fong Yuman C. , DeMatteo Ronald P. , Allen Peter J. , Shia Jinru , Ang Celina , Vakiani Efsevia , D'Angelica Michael I. 
Published: August 2014

BACKGROUNDThe validity of the KRAS mutation as a predictor of recurrence‐free survival (RFS) or overall survival (OS) is unclear. The current study investigated whether the presence of the KRAS mutation decreased RFS or OS in patients with colorectal cancer who underwent liver resection.METHODSPatients with resected colorectal liver metastases who received adjuvant hepatic arterial infusion plus systemic therapy and for whom KRAS data was available were evaluated. Correlation between KRAS and clinical factors was done using the Fisher exact test. Kaplan‐Meier methods were used to estimate the median RFS and OS.RESULTSA total of 169 patients were evaluated, 118 of whom had KRAS wild‐type (WT) and 51 had KRAS mutated (MUT) tumors. The 3‐year RFS rate was 46% for patients with KRAS WT (95% confidence interval [95% CI], 35%‐56%) and 30% (95% CI, 16%‐44%) for patients with KRAS MUT (P =.005). The 3‐year OS rate was 95% (95% CI, 87%‐98%) and 81% (95% CI, 62%‐95%), respectively, for patients with KRAS WT and KRAS MUT (P =.07). On multivariate analysis, KRAS remained a significant predictor of RFS (hazard ratio, 1.9). The 3‐year cumulative recurrence rate by site of metastases was as follows: 2% versus 13.4% for bone (P≤.01), 2% versus 14.5% for brain (P =.05), 33.2% versus 58% for lung (P≤.01), and 30% versus 47% for liver (P =.10) in patients with KRAS WT versus KRAS MUT.CONCLUSIONSIn the current study, among patients with resected colorectal liver metastases who were treated with adjuvant hepatic arterial infusion plus systemic therapy, patients with KRAS MUT were found to have a significantly worse 3‐year RFS (30%) compared with KRAS WT (46%) p=.005. The cumulative incidence of bone, brain, and lung metastases was significantly higher for patients with KRAS MUT compared with those with KRAS WT. Cancer 2014;120:3965–3971. © 2014 American Cancer Society.
Cancer survivors' uptake and adherence in diet and exercise intervention trials: An integrative data analysis
Authors: Adams Rebecca N. , Mosher Catherine E. , Blair Cindy K. , Snyder Denise C. , Sloane Richard , Demark‐Wahnefried Wendy 
Published: August 2014

BACKGROUNDThe health benefits of diet and exercise interventions for cancer survivors are well documented. However, little is known regarding demographic and medical predictors of survivors' willingness to participate in diet and exercise intervention trials, study enrollment, intervention adherence, and study completion. To assist in interpreting the generalizability of trial findings and to improve the design of future trials, this study examined predictors of these process measures.METHODSAn integrative data analysis was performed on data from 3 of the largest home‐based diet and exercise intervention trials for cancer survivors (n = 23,841). Demographic and medical factors (ie, sex, race, age, time since diagnosis, and cancer type) were examined as predictors of willingness to participate, study enrollment, intervention adherence, and study completion in the pooled sample. A 99% confidence interval was used to determine statistical significance.RESULTSAcross trials, 11.1% of contacted survivors were willing to participate, and 5.7% were eligible and enrolled. Among enrollees, 53.4% demonstrated ≥75% adherence to the intervention, and 91.1% completed the study. Race (Caucasian vs others), age, time since diagnosis, and cancer type predicted survivors' willingness to participate (P < .01). All examined predictors were associated with the likelihood of study enrollment (P < .01). No significant predictors of intervention adherence or study completion were found among study enrollees (P ≥ .01).CONCLUSIONSCancer survivors' demographic and medical characteristics predicted their interest and participation in diet and exercise intervention trials. These findings have implications for the generalizability of results and can help to guide procedures used in future trials to enhance patient representation. Cancer 2015;121:77–83. © 2014 American Cancer Society.
Trends in central nervous system tumor incidence relative to other common cancers in adults, adolescents, and children in the United States, 2000 to 2010
Authors: Gittleman Haley R. , Ostrom Quinn T. , Rouse Chaturia D. , Dowling Jacqueline A. , de Blank Peter M. , Kruchko Carol A. , Elder J. Bradley , Rosenfeld Steven S. , Selman Warren R. , Sloan Andrew E. , Barnholtz‐Sloan Jill S. 
Published: August 2014

BACKGROUNDTime trends in cancer incidence rates (IR) are important to measure the changing burden of cancer on a population over time. The overall IR of cancer in the United States is declining. Although central nervous system tumors (CNST) are rare, they contribute disproportionately to mortality and morbidity. In this analysis, the authors examined trends in the incidence of the most common cancers and CNST between 2000 and 2010.METHODSThe current analysis used data from the United States Cancer Statistics publication and the Central Brain Tumor Registry of the United States. Age‐adjusted IR per 100,000 population with 95% confidence intervals and the annual percent change (APC) with 95% confidence intervals were calculated for selected common cancers and CNST overall and by age, sex, race/ethnicity, selected histologies, and malignancy status.RESULTSIn adults, there were significant decreases in colon (2000‐2010: APC, −3.1), breast (2000‐2010: APC, −0.8), lung (2000‐2010: APC, −1.1), and prostate (2000‐2010: APC, −2.4) cancer as well as malignant CNST (2008‐2010: APC, −3.1), but a significant increase was noted in nonmalignant CNST (2004‐2010: APC, 2.7). In adolescents, there were significant increases in malignant CNST (2000‐2008: APC, 1.0) and nonmalignant CNST (2004‐2010: APC, 3.9). In children, there were significant increases in acute lymphocytic leukemia (2000‐2010: APC, 1.0), non‐Hodgkin lymphoma (2000‐2010: APC, 0.6), and malignant CNST (2000‐2010: APC, 0.6).CONCLUSIONSSurveillance of IR trends is an important way to measure the changing public health and economic burden of cancer. In the current study, there were significant decreases noted in the incidence of adult cancer, whereas adolescent and childhood cancer IR were either stable or increasing. Cancer 2015;121:102–112. © 2014 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.
Selective Extraction of Metal Ions from Aqueous Phase to Ionic Liquids: A Novel Thermodynamic Approach to Separations
Authors: Janssen Camiel H. C. , Sánchez Antonio , Kobrak Mark N. 
Published: August 2014

AbstractThe selective extraction of metals from aqueous mixtures has generally relied on the use of selective ionophores. We present an alternative strategy that exploits a recently developed approach to extraction into an ionic liquid phase, and show that a high degree of control over selectivity can be obtained by tuning the relative concentrations of extraction agents. A thermodynamic model for the approach is presented, and an experimental separation of strontium and potassium ions is performed. It is shown that tuning the concentrations of the species involved can shift the ratio of potassium to strontium in the ionic liquid phase from 4:1 to 3:4. This extraction is performed under mild conditions with relatively common reagents. The result is a proof‐of‐concept for a novel separations scheme that could have great importance in a wide range of technological applications.
An improved protocol for flow cytometry analysis of phytoplankton cultures and natural samples
Authors: Marie Dominique , Rigaut‐Jalabert Fabienne , Vaulot Daniel 
Published: August 2014

AbstractPreservation of cells, choice of fixative, storage, and thawing conditions are recurrent issues for the analysis of phytoplankton by flow cytometry. We examined the effects of addition of the surfactant Pluronic F68 to glutaraldehyde‐fixed photosynthetic organisms in cultures and natural samples. In particular, we examined cell losses and modifications of side scatter (a proxy of cell size) and fluorescence of natural pigments. We found that different marine phytoplankton species react differently to the action of Pluronic F68. In particular, photosynthetic prokaryotes are less sensitive than eukaryotes. Observed cell losses may result from cell lysis or from cell adhesion to the walls of plastic tubes that are commonly used for flow cytometry analysis. The addition of the surfactant, Pluronic F68, has a positive effect on cells for long‐term storage. We recommend to modify current protocols for preservation of natural marine planktonic samples, by fixing them with glutaraldehyde 0.25% (final concentration) and adding Pluronic F68 at a final concentration of 0.01% in the samples before preservation. Pluronic F68 also appears effective for preserving samples without fixation for subsequent sorting, e.g. for molecular biology analyses. © 2014 International Society for Advancement of Cytometry
Electrochemical Implication of a Hydrogen‐Bonded Imidazole on a Redox‐Active‐Bound Phenolate Group
Authors: El Ghachtouli Sanae , Lassalle‐Kaiser Benedikt , Guillot Régis , Aukauloo Ally 
Published: August 2014

AbstractWe report the synthesis of a pentadentate N4O ligand with an imidazole group in the ortho position of the phenol group. The syntheses and crystallographic structures are reported for zinc(II) complexes by using the previously reported tert‐butyl‐substituted ligand and the imidazole‐substituted ligand in two different protonation states. We describe the influence of the ortho substituent (tert‐butyl, imidazole, and imidazolium) on the electrochemical behavior of the zinc(II) complexes. The substitution of the tert‐butyl group in the ortho position by an imidazole group shifts the oxidation potential of the phenolate by more than 300 mV. The o‐tert‐butyl‐substituted ligand allows the formation of a stable radical phenoxylzinc(II) complex upon electrochemical oxidation, but it is unstable in the case of the imidazole‐substituted complex. The imidazole‐substituted ligand can be reversibly protonated without altering the electrochemical properties of the phenolate group.
A Nickel‐Containing Model System of Acireductone Dioxygenases that Utilizes a C(1)‐H Acireductone Substrate
Authors: Allpress Caleb J. , Berreau Lisa M. 
Published: August 2014

AbstractA mononuclear NiII complex bearing the monoanion of 1‐acetoxy‐3‐phenylpropane‐2,3‐dione (4) as a ligand has been prepared {[(6‐Ph2TPA)Ni{PhC(O)C(O)CHOC(O)CH3)]ClO4, 5; 6‐Ph2TPA = N,N‐bis[(6‐phenyl‐2‐pyridyl)methyl]‐N‐(2‐pyridylmethyl)amine}. This complex was characterized by 1H NMR, UV/Vis and IR spectroscopy, mass spectrometry, and elemental analysis. Exposure of solutions of 5 to O2 did not result in any reaction over the course of hours. Deprotection of 5 by the addition of NaOCH3 in methanol generated a NiII species (6) that contains a coordinated dianionic C(1)‐H acireductone. Exposure of 6 to O2 led to regioselective oxidative cleavage reactivity akin to that found for the NiII‐containing acireductone dioxygenase enzyme. The strategy outlined herein is the first synthetic approach that enables examination of the oxidative reactivity of a synthetic NiII species containing a dianionic C(1)‐H acireductone ligand.
Ethnic identity and self‐esteem among Asian and European Americans: When a minority is the majority and the majority is a minority
Authors: Xu Yiyuan , Farver Jo Ann M. , Pauker Kristin 
Published: August 2014

AbstractThree studies were conducted to examine the impact of being a numeric majority or minority in Hawai'i and U.S. mainland on the ethnic identity and self‐esteem of Asian and European Americans. Results of Study 1 (N = 214, M age = 19.85 years) and Study 2 (N = 215, M age = 18.20 years) showed that Asian Americans who grew up on the U.S. mainland, where they are a numeric minority, reported higher ethnic identity than did Asian Americans who grew up in Hawai'i, where they are a numeric majority. In addition, ethnic identity was significantly associated with self‐esteem for Asian Americans from the U.S. mainland and European Americans from Hawai'i (numeric minority), but not for Asian Americans from Hawai'i and European Americans from the U.S. mainland (numeric majority). Study 3 (N = 88, M age = 18.12) examined ethnic identity and self‐esteem among Asian and European Americans who had moved from the U.S. mainland to attend a university in Hawai'i over a 1 year time period. The results showed significant relations between ethnic identity and self‐esteem for Asian Americans when they initially moved to Hawai'i, but this relation decreased after they had lived in Hawai'i for 1 year. The findings highlight contextual variations in ethnic identity and self‐esteem for members of both minority and majority groups in the U.S. Copyright © 2014 John Wiley & Sons, Ltd.
Catalytic conversion of carbon dioxide to carboxylic acid derivatives
Authors: Liu An‐Hua , Yu Bing , He Liang‐Nian 
Published: August 2014

AbstractChemical utilization of the greenhouse gas, i.e., CO2 as an abundant, easily available, and renewable carbon feedstock for producing chemicals, materials, and fuels is attractive as an integral part of the carbon cycle. Based on the principle of CO2 activation and elaborately designed catalysts, various transformation of CO2 can be realized under mild conditions. In particular, establishing practical methodologies for catalytic carboxylation by CO2 as carboxylative reagent would be a fascinating dream for synthetic chemists. This review covers the updated advances in the catalytic conversion of CO2 into carboxylic acid derivatives from alkenes, alkynes, aromatic halides, aromatic C(sp2)‐H bonds, etc.
H.M.'s contributions to neuroscience: A review and autopsy studies
Authors: Augustinack Jean C. , van der Kouwe André J.W. , Salat David H. , Benner Thomas , Stevens Allison A. , Annese Jacopo , Fischl Bruce , Frosch Matthew P. , Corkin Suzanne 
Published: August 2014

ABSTRACTH.M., Henry Molaison, was one of the world's most famous amnesic patients. His amnesia was caused by an experimental brain operation, bilateral medial temporal lobe resection, carried out in 1953 to relieve intractable epilepsy. He died on December 2, 2008, and that night we conducted a wide variety of in situ MRI scans in a 3 T scanner at the Massachusetts General Hospital (Mass General) Athinoula A. Martinos Center for Biomedical Imaging. For the in situ experiments, we acquired a full set of standard clinical scans, 1 mm isotropic anatomical scans, and multiple averages of 440 μm isotropic anatomical scans. The next morning, H.M.'s body was transported to the Mass General Morgue for autopsy. The photographs taken at that time provided the first documentation of H.M.'s lesions in his physical brain. After tissue fixation, we obtained ex vivo structural data at ultra‐high resolution using 3 T and 7 T magnets. For the ex vivo acquisitions, the highest resolution images were 210 μm isotropic. Based on the MRI data, the anatomical areas removed during H.M.'s experimental operation were the medial temporopolar cortex, piriform cortex, virtually all of the entorhinal cortex, most of the perirhinal cortex and subiculum, the amygdala (except parts of the dorsal‐most nuclei—central and medial), anterior half of the hippocampus, and the dentate gyrus (posterior head and body). The posterior parahippocampal gyrus and medial temporal stem were partially damaged. Spared medial temporal lobe tissue included the dorsal‐most amygdala, the hippocampal‐amygdalo‐transition‐area, ∼2 cm of the tail of the hippocampus, a small part of perirhinal cortex, a small portion of medial hippocampal tissue, and ∼2 cm of posterior parahippocampal gyrus. H.M.'s impact on the field of memory has been remarkable, and his contributions to neuroscience continue with a unique dataset that includes in vivo, in situ, and ex vivo high‐resolution MRI. © 2014 Wiley Periodicals, Inc.
Intracellular metabolic flux analysis of CHO cells supplemented with wheat hydrolysates for improved mAb production and cell‐growth
Authors: Lee Hae Woo , Christie Andrew , Starkey Jason A. , Read Erik K. , Yoon Seongkyu 
Published: August 2014

AbstractBACKGROUNDIn the production of therapeutic proteins using Chinese hamster ovary (CHO) cell culture, the compositional variability in raw materials is often poorly understood. To elucidate the effects of raw material variability in regulating the intracellular metabolic pathways, plant‐derived supplements of wheat hydrolysates were employed as a model system of raw materials having high compositional variability. The intracellular metabolic fluxes of antibody‐producing GS‐CHO cells supplemented with different lots of wheat hydrolysates were quantified using the techniques of flux balance analysis (FBA).RESULTSThe examination of the metabolic flux clearly illustrated several unique metabolic features. Specifically, under the given environmental conditions induced by the variability of the different wheat hydrolysate lots, the serine and glycine metabolism could be linked to improved cell growth, while the elevated levels of the anaplerotic reaction and the TCA cycle could be related to the increased specific antibody production. Multivariate data analysis revealed the detailed metabolic regulations of a GS‐CHO cell line in response to the compositional variability of the given raw materials. The study result can be used for targeted optimization of cell growth and monoclonal antibody production.CONCLUSIONMetabolic flux analysis coupled with multivariate data analytics unravel the complicated effects of raw material variability on the cellular metabolism, and hence improve the overall productivity of an antibody‐producing CHO cell culture. © 2014 Society of Chemical Industry