bluuebunny/crossref_metadata_2025_split huggingface dataset:
Codability of industry and occupation information from cancer registry records: Differences by patient demographics, casefinding source, payor, and cancer type
Authors: Silver Sharon R. , Tsai Rebecca J. , Morris Cyllene R. , Boiano James M. , Ju Jun , Scocozza Marilyn S. , Calvert Geoffrey M. 
Published: March 2018

IntroductionIndustry and occupation (I&O) information collected by cancer registries is useful for assessing associations among jobs and malignancies. However, systematic differences in I&O availability can bias findings.MethodsCodability by patient demographics, payor, identifying (casefinding) source, and cancer site was assessed using I&O text from first primaries diagnosed 2011‐2012 and reported to California Cancer Registry. I&O were coded to a U.S. Census code or classified as blank/inadequate/unknown, retired, or not working for pay.ResultsIndustry was codable for 37% of cases; 50% had “unknown” and 9% “retired” instead of usual industry. Cases initially reported by hospitals, covered by preferred providers, or with known occupational etiology had highest codable industry; cases from private pathology laboratories, with Medicaid, or diagnosed in outpatient settings had least. Occupation results were similar.ConclusionsRecording usual I&O for retirees and improving linkages for reporting entities without patient access would improve I&O codability and research validity.
Risk factors associated with allergic sensitization and asthma phenotypes among poultry farm workers
Authors: Ngajilo Dorothy , Singh Tanusha , Ratshikhopha Edith , Dayal Payal , Matuka Onnicah , Baatjies Roslynn , Jeebhay Mohamed F. 
Published: March 2018

BackgroundThis study investigated the risk factors for occupational allergic sensitization and various asthma phenotypes in poultry‐workers.MethodsA cross‐sectional study of 230 workers used a modified ECRHS questionnaire, spirometry, FeNO, Phadiatop, and sIgE to poultry farming related allergens.ResultsWorker's mean age was 37 ± 9 years, 68% male, 43% current‐smokers, 34% atopic, and 5% casual‐workers. The prevalence of non‐atopic asthma (NAA = 7%) was higher than atopic‐asthma (AA = 5%) and probable allergic occupational‐asthma (OA = 3%). Sensitization to at least one poultry farming related allergen was 24%. Workers sensitized to chicken‐specific‐allergens were more likely to be atopic (ORunadj = 20.9, 95%CI: 4.7‐93.2) or employed as casual‐workers (ORunadj = 6.0, 95%CI: 1.1‐35.9). Work‐related chest symptoms were associated the rearing‐department (ORadj = 3.2, 95%CI: 1.2‐8.4) and exposure to high gas/dust/fumes (ORadj = 4.8, 95%CI: 2.4‐9.5). Airflow reversibility (ORadj = 10.9, 95%CI: 2.0‐60.3) was significantly associated with casual‐work status.ConclusionAllergic and non‐allergic mechanisms play a role in asthma development among poultry‐workers with casual workers demonstrating increased risk.
Clinical and laboratory factors contributing to uninterpretable beryllium lymphocyte proliferation tests (BeLPT)
Authors: Smith Derek E. , Golden Ashley P. , Stange Arthur W. , Barker Elizabeth , Mroz Margaret , Barón Anna E. , Ghosh Debashis , Maier Lisa , Cragle Donna , Newman Lee S. 
Published: March 2018

BackgroundThe beryllium lymphocyte proliferation test (BeLPT), has become the principal clinical test for detecting beryllium sensitization and chronic beryllium disease. Uninterpretable BeLPT results can occur in a small but significant proportion of tests from poor lymphocyte growth (PG) or over proliferation of lymphocytes (OP). The clinical and laboratory causes of uninterpretable results are not known.MethodsBeLPT data from the US Department of Energy‐supported Former Worker Screening Program were analyzed for a 10‐year period. Drivers of uninterpretable BeLPTs were investigated using multivariable models and classification techniques.ResultsThree participant attributes were significantly associated with PG, while OP showed no significant associations. Serum lot for the lymphocyte growth medium accounted for 21% of the variation in PG and 16% in OP.ConclusionSerum lots influence the likelihood of having uninterpretable BeLPT. To better understand uninterpretable results and possibly reduce their occurrence, additional laboratory‐related factors should be addressed.
Salicylate‐Directed C−O Bond Cleavage: Iron‐Catalyzed Allylic Substitution with Grignard Reagents
Authors: Ma Enlu , Jiang Yifan , Chen Yuanjin , Qi Longying , Yan Xiaoyu , Li Zhiping 
Published: March 2018

AbstractSelective C−O bond cleavage is of high interest for modern organic synthesis. A strategy for selective allylic C−O bond cleavage using ethyl salicylate as a directing leaving group has been developed. The reaction is initiated by the chelation of the ortho‐ester phenolic group with iron catalyst. The π‐allyl iron intermediate is generated and reacts with Grignard reagents to give the allylic substitution products. The excellent selectivity of C−O bond cleavage is achieved in multiple allylic C−O bond‐containing substrates with the aid of the salicylate‐directed strategy.
Neurochemical abnormalities in premanifest and early spinocerebellar ataxias
Authors: Joers James M. , Deelchand Dinesh K. , Lyu Tianmeng , Emir Uzay E. , Hutter Diane , Gomez Christopher M. , Bushara Khalaf O. , Eberly Lynn E. , Öz Gülin 
Published: March 2018

ObjectiveTo investigate whether early neurochemical abnormalities are detectable by high‐field magnetic resonance spectroscopy (MRS) in individuals with spinocerebellar ataxias (SCAs) 1, 2, 3, and 6, including patients without manifestation of ataxia.MethodsA cohort of 100 subjects (N = 18–21 in each SCA group, including premanifest mutation carriers; mean score on the Scale for the Assessment and Rating of Ataxia [SARA] <10 for all genotypes, and 22 matched controls) was scanned at 7 Tesla to obtain neurochemical profiles of the cerebellum and brainstem. A novel multivariate approach (distance‐weighted discrimination) was used to combine regional profiles into an “MRS score.”ResultsMRS scores robustly distinguished individuals with SCA from controls, with misclassification rates of 0% (SCA2), 2% (SCA3), 5% (SCA1), and 17% (SCA6). Premanifest mutation carriers with estimated disease onset within 10 years had MRS scores in the range of early‐manifest SCA subjects. Levels of neuronal and glial markers significantly correlated with SARA and an Activities of Daily Living score in subjects with SCA. Regional neurochemical alterations were different between SCAs at comparable disease severity, with SCA2 displaying the most extensive neurochemical abnormalities, followed by SCA1, SCA3, and SCA6.InterpretationNeurochemical abnormalities are detectable in individuals before manifest disease, which may allow premanifest enrollment in future SCA trials. Correlations with ataxia and quality‐of‐life scores show that neurochemical levels can serve as clinically meaningful endpoints in trials. Ranking of SCA types by degree of neurochemical abnormalities indicates that the neurochemistry may reflect synaptic function or density. Ann Neurol 2018;83:816–829
Evidence for the Role of Intracellular Water Lifetime as a Tumour Biomarker Obtained by In Vivo Field‐Cycling Relaxometry
Authors: Ruggiero Maria Rosaria , Baroni Simona , Pezzana Stefania , Ferrante Gianni , Geninatti Crich Simonetta , Aime Silvio 
Published: March 2018

AbstractIt was established through in vivo T1 measurements at low magnetic fields that tumour cells display proton T1 values that are markedly longer than those shown by healthy tissue. Moreover, it has been found that the elongation of T1 parallels the aggressiveness of the investigated tumour. The T1 lengthening is associated with an enhanced water exchange rate across the transcytolemmal membrane through an overexpression/upregulation of GLUT1 and Na+/K+ ATPase transporters. It follows that the intracellular water lifetime represents a hallmark of tumour cells that can be easily monitored by measuring T1 at different magnetic field strengths ranging from 0.2 to 200 mT.
Vesicle Tubulation with Self‐Assembling DNA Nanosprings
Authors: Grome Michael W. , Zhang Zhao , Pincet Frédéric , Lin Chenxiang 
Published: March 2018

AbstractA major goal of nanotechnology and bioengineering is to build artificial nanomachines capable of generating specific membrane curvatures on demand. Inspired by natural membrane‐deforming proteins, we designed DNA‐origami curls that polymerize into nanosprings and show their efficacy in vesicle deformation. DNA‐coated membrane tubules emerge from spherical vesicles when DNA‐origami polymerization or high membrane‐surface coverage occurs. Unlike many previous methods, the DNA self‐assembly‐mediated membrane tubulation eliminates the need for detergents or top‐down manipulation. The DNA‐origami design and deformation conditions have substantial influence on the tubulation efficiency and tube morphology, underscoring the intricate interplay between lipid bilayers and vesicle‐deforming DNA structures.
Reversible Switching between Highly Porous and Nonporous Phases of an Interpenetrated Diamondoid Coordination Network That Exhibits Gate‐Opening at Methane Storage Pressures
Authors: Yang Qing‐Yuan , Lama Prem , Sen Susan , Lusi Matteo , Chen Kai‐Jie , Gao Wen‐Yang , Shivanna Mohana , Pham Tony , Hosono Nobuhiko , Kusaka Shinpei , Perry John J. , Ma Shengqian , Space Brian , Barbour Leonard J. , Kitagawa Susumu , Zaworotko Michael J. 
Published: March 2018

AbstractHerein, we report that a new flexible coordination network, NiL2 (L=4‐(4‐pyridyl)‐biphenyl‐4‐carboxylic acid), with diamondoid topology switches between non‐porous (closed) and several porous (open) phases at specific CO2 and CH4 pressures. These phases are manifested by multi‐step low‐pressure isotherms for CO2 or a single‐step high‐pressure isotherm for CH4. The potential methane working capacity of NiL2 approaches that of compressed natural gas but at much lower pressures. The guest‐induced phase transitions of NiL2 were studied by single‐crystal XRD, in situ variable pressure powder XRD, synchrotron powder XRD, pressure‐gradient differential scanning calorimetry (P‐DSC), and molecular modeling. The detailed structural information provides insight into the extreme flexibility of NiL2. Specifically, the extended linker ligand, L, undergoes ligand contortion and interactions between interpenetrated networks or sorbate–sorbent interactions enable the observed switching.
Site‐Selective Cysteine–Cyclooctyne Conjugation
Authors: Zhang Chi , Dai Peng , Vinogradov Alexander A. , Gates Zachary P. , Pentelute Bradley L. 
Published: March 2018

AbstractWe report a site‐selective cysteine–cyclooctyne conjugation reaction between a seven‐residue peptide tag (DBCO‐tag, Leu‐Cys‐Tyr‐Pro‐Trp‐Val‐Tyr) at the N or C terminus of a peptide or protein and various aza‐dibenzocyclooctyne (DBCO) reagents. Compared to a cysteine peptide control, the DBCO‐tag increases the rate of the thiol–yne reaction 220‐fold, thereby enabling selective conjugation of DBCO‐tag to DBCO‐linked fluorescent probes, affinity tags, and cytotoxic drug molecules. Fusion of DBCO‐tag with the protein of interest enables regioselective cysteine modification on proteins that contain multiple endogenous cysteines; these examples include green fluorescent protein and the antibody trastuzumab. This study demonstrates that short peptide tags can aid in accelerating bond‐forming reactions that are often slow to non‐existent in water.
Inhibition of α‐Synuclein Amyloid Fibril Elongation by Blocking Fibril Ends
Authors: Shvadchak Volodymyr V. , Afitska Kseniia , Yushchenko Dmytro A. 
Published: March 2018

AbstractMisfolding of the protein α‐synuclein (αSyn) into amyloid fibrils plays a central role in the development of Parkinson's disease. Most approaches for the inhibition of αSyn fibril formation are based on stabilizing the native monomeric form of the protein or destabilizing the fibrillized misfolded form. They require high concentrations of inhibitor and therefore cannot be easily used for therapies. In this work, we designed an inhibitor (Inh‐β) that selectively binds the growing ends of αSyn fibrils and creates steric hindrance for the binding of monomeric αSyn. This approach permits the inhibition of fibril formation at Inh‐β concentrations (IC50=850 nm) much lower than the concentration of monomeric αSyn. We studied its kinetic mechanism in vitro and identified the reactions that limit inhibition efficiency. It is shown that blocking of αSyn fibril ends is an effective approach to inhibiting fibril growth and provides insights for the development of effective inhibitors of αSyn aggregation.
Photoinduced Copper‐Catalyzed Coupling of Terminal Alkynes and Alkyl Iodides
Authors: Hazra Avijit , Lee Mitchell T. , Chiu Justin F. , Lalic Gojko 
Published: March 2018

AbstractWe have developed a photoinduced copper‐catalyzed alkylation of terminal alkynes with primary, secondary, or tertiary alkyl iodides as electrophiles. The reaction has a broad substrate scope and can be successfully performed in the presence of ester, nitrile, aryl halide, ketone, sulfonamide, epoxide, alcohol, and amide functional groups. The alkylation is promoted by blue light (λ≈450 nm) and proceeds at room temperature in the absence of any additional metal catalysts. The use of a terpyridine ligand is essential for the success of the reaction and is shown to prevent photoinduced copper‐catalyzed polymerization of the starting materials.
Iridium‐Catalyzed Sequential Silylation and Borylation of Heteroarenes Based on Regioselective C−H Bond Activation
Authors: Murai Masahito , Nishinaka Naoki , Takai Kazuhiko 
Published: March 2018

AbstractAn iridium‐catalyzed regioselective sequential silylation and borylation of heteroarenes was developed, which represents a rare example of unsymmetrical intermolecular C−H bond difunctionalization through the introduction of two different functionalities during a one‐pot transformation. Although the substrate scope for the dehydrogenative silylation of heteroarenes has been limited mainly to electron‐rich five‐membered rings, the current reaction proceeds with both electron‐rich and electron‐deficient heteroarenes with the aid of heteroatom‐directing C−H bond activation. The regioselectivity of the second borylation was controlled by both steric factors and the electronic effect of the silyl group installed in the first step. In combination with the classic cross‐coupling reaction, this method provides rapid access to multisubstituted heteroarenes.
Measuring Spin Relaxation Rates Using Satellite Exchange NMR Spectroscopy
Authors: Robertson Gerard P. , Odell Barbara , Kuprov Ilya , Dixon Darren J. , Claridge Tim D. W. 
Published: March 2018

AbstractAn approach to the indirect measurement of nuclear spin relaxation rates of low‐magnetogyric ratio (γ) nuclei using the process of satellite exchange is described. The method does not require the observation of, or even the ability to provide radio‐frequency pulses to, the low‐γ nucleus, but requires this to be scalar coupled to an NMR observable nucleus, such as 31P or 1H, making it especially attractive for the study of diamagnetic transition metals. In situations where spin relaxation is dominated by chemical shift anisotropy (CSA), the determination of the longitudinal spin relaxation time constant (T1) of the metal becomes possible, as illustrated for 195Pt and 107/109Ag.
Facile Synthesis of Chiral Cyclic Ureas through Hydrogenation of 2‐Hydroxypyrimidine/Pyrimidin‐2(1H)‐one Tautomers
Authors: Feng Guang‐Shou , Chen Mu‐Wang , Shi Lei , Zhou Yong‐Gui 
Published: March 2018

AbstractA facile access to optically active cyclic ureas was developed through palladium‐catalyzed asymmetric hydrogenation of pyrimidines containing tautomeric hydroxy group with up to 99 % ee. Mechanistic studies indicated that reaction pathway proceed through hydrogenation of C=N of the oxo tautomer pyrimidin‐2(1H)‐one, acid‐catalyzed isomerization of enamine–imine, and hydrogenation of imine pathway. In addition, the chiral cyclic ureas are readily converted into useful chiral 1,3‐diamine and thiourea derivatives without loss of optical purity.
Fluorogenic Ag+–Tetrazolate Aggregation Enables Efficient Fluorescent Biological Silver Staining
Authors: Xie Sheng , Wong Alex Y. H. , Kwok Ryan T. K. , Li Ying , Su Huifang , Lam Jacky W. Y. , Chen Sijie , Tang Ben Zhong 
Published: March 2018

AbstractSilver staining, which exploits the special bioaffinity and the chromogenic reduction of silver ions, is an indispensable visualization method in biology. It is a most popular method for in‐gel protein detection. However, it is limited by run‐to‐run variability, background staining, inability for protein quantification, and limited compatibility with mass spectroscopic (MS) analysis; limitations that are largely attributed to the tricky chromogenic visualization. Herein, we reported a novel water‐soluble fluorogenic Ag+ probe, the sensing mechanism of which is based on an aggregation‐induced emission (AIE) process driven by tetrazolate‐Ag+ interactions. The fluorogenic sensing can substitute the chromogenic reaction, leading to a new fluorescence silver staining method. This new staining method offers sensitive detection of total proteins in polyacrylamide gels with a broad linear dynamic range and robust operations that rival the silver nitrate stain and the best fluorescent stains.
Platzierung einzelner Proteine in den SERS‐Hot‐Spots selbstorganisierter Silbernanolinsen
Authors: Heck Christian , Kanehira Yuya , Kneipp Janina , Bald Ilko 
Published: March 2018

AbstractDiese Studie demonstriert die Bottom‐up‐Synthese von Silbernanolinsen. Ein robustes Beschichtungsprotokoll ermöglichte die Funktionalisierung unterschiedlich großer Silbernanopartikel mit einzelsträngiger DNA unterschiedlicher Sequenz. Derartig beschichtete Partikel mit Durchmessern von 10 nm, 20 nm und 60 nm wurden mithilfe von DNA‐Origami‐Gerüsten zu Silbernanolinsen angeordnet. Ein einzelnes Molekül des Proteins Streptavidin ist in demjenigen Spalt zwischen den Partikeln immobilisiert worden, der die höchste Feldverstärkung zur Verfügung stellt. Streptavidin war dabei mit Alkin‐Gruppen modifiziert und fungierte als Modellanalyt in Experimenten zur oberflächenverstärkten Raman‐Streuung (SERS). Korrelierte Raman‐ und Rasterkraftmikroskopie‐Messungen ermöglichten die Aufnahme von SERS‐Signalen der Alkingruppen eines einzelnen Streptavidins, von einer einzelnen Silbernanolinse. Diese diskreten, selbstähnlichen Silbernanopartikelaggregate versprechen vielfältige Anwendungen im Feld der Plasmonik.
Alkyl Ethers as Traceless Hydride Donors in Brønsted Acid Catalyzed Intramolecular Hydrogen Atom Transfer
Authors: Gandamana Dhika Aditya , Wang Bin , Tejo Ciputra , Bolte Benoit , Gagosz Fabien , Chiba Shunsuke 
Published: March 2018

AbstractA new protocol for the deoxygenation of alcohols and the hydrogenation of alkenes under Brønsted acid catalysis has been developed. The method is based on the use of either a benzyl or isopropyl ether as a traceless hydrogen‐atom donor, and involves an intramolecular hydride transfer as a key step, which is achieved in a regio‐ and stereoselective manner.
Indyllithium and the Indyl Anion [InL]−: Heavy Analogues of N‐Heterocyclic Carbenes
Authors: Schwamm Ryan J. , Anker Mathew D. , Lein Matthias , Coles Martyn P. , Fitchett Christopher M. 
Published: March 2018

AbstractReduction of the indate complex In(NONAr)(μ‐Cl)2Li(OEt2)2 (NONAr=[O(SiMe2NAr)2]2−; Ar=2,6‐iPr2C6H3) with sodium generates the InII diindane species [In(NONAr)]2. Further reduction with a mixture of potassium and [2.2.2]crypt affords the InI N‐heterocyclic indyl anion [In(NONAr)]−, which crystallizes with a non‐contacted [K([2.2.2]crypt)]+ cation. The indyl anion can also be isolated as the indyllithium compound In(NONAr)(Li{THF}3), which contains an In−Li bond. Density functional theory calculations show that the HOMO of the indyl anion is a metal‐centred lone pair, and preliminary reactivity studies confirm its nucleophilic behaviour.
Localizing Antifungal Drugs to the Correct Organelle Can Markedly Enhance their Efficacy
Authors: Benhamou Raphael I. , Bibi Maayan , Berman Judith , Fridman Micha 
Published: March 2018

AbstractA critical aspect of drug design is optimal target inhibition by specifically delivering the drug molecule not only to the target tissue or cell but also to its therapeutically active site within the cell. This study demonstrates, as a proof of principle, that drug efficacy can be increased considerably by a structural modification that targets it to the relevant organelle. Specifically, by varying the fluorescent dye segment an antifungal azole was directed from the fungal cell mitochondria to the endoplasmic reticulum (ER), the organelle that harbors the drug target. The ER‐localized azole displayed up to two orders of magnitude improved antifungal activity and also dramatically reduced the growth of drug‐tolerant fungal subpopulations in a panel of Candida species, which are the most prevalent causes of serious human fungal infections. The principle underlying the “target organelle localization” approach provides a new paradigm to improve drug potency and replenish the limited pipeline of antifungal drugs.
Bioinspired Oxidative Cyclization of the Geissoschizine Skeleton for the Total Synthesis of (−)‐17‐nor‐Excelsinidine
Authors: Jarret Maxime , Tap Aurélien , Kouklovsky Cyrille , Poupon Erwan , Evanno Laurent , Vincent Guillaume 
Published: March 2018

AbstractWe report the first total synthesis of (−)‐17‐nor‐excelsinidine, a zwitterionic monoterpene indole alkaloid that displays an unusual N4−C16 connection. Inspired by the postulated biosynthesis, we explored an oxidative coupling approach from the geissoschizine framework to forge the key ammonium–acetate connection. Two strategies allowed us to achieve this goal, namely an intramolecular nucleophilic substitution on a 16‐chlorolactam with the N4 nitrogen atom or a direct I2‐mediated N4−C16 oxidative coupling from the enolate of geissoschizine.
Transition‐Metal‐Like Behavior of Monovalent Boron Compounds: Reduction, Migration, and Complete Cleavage of CO at a Boron Center
Authors: Wang Hao , Wu Linlin , Lin Zhenyang , Xie Zuowei 
Published: March 2018

AbstractThe borylene–carbonyl moiety in [bis(silylene)B(CO)][WBr(CO)5] shows diverse reactivity. Reduction, migration, and complete cleavage of CO have been observed at the boron center, leading to the formation of new types of borylenes. These reactions not only serve as new methods for the synthesis of various stable borylenes, but also demonstrate that main‐group‐element compounds can mimic the behavior of transition‐metal complexes.
Sulfoximidations of Benzylic C−H bonds by Photocatalysis
Authors: Wang Han , Zhang Duo , Bolm Carsten 
Published: March 2018

AbstractAn efficient photocatalytic functionalization of compounds with benzylic C−H bonds by sulfoximidation in visible light is described. The mild reaction conditions allow the use of a broad array of substrates, including diarylmethane, alkyl arenes, arylacetonitrile, 2‐arylacetate, and alkynyl aryl methanes. The sulfoximidation process is highly chemoselective and leads to the corresponding sulfoximines in generally good yields. Mechanistic investigations suggested the intermediacy of sulfoximidoyl radicals.