bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanistic Aspects in the Formation, Growth and Surface Functionalization of Metal Oxide Nanoparticles in Organic Solvents
Authors: Deshmukh Rupali , Niederberger Markus 
Published: April 2017

AbstractThe synthesis of metal oxide nanoparticles in organic solvents, so‐called nonaqueous (or nonhydrolytic) processes represent powerful alternatives to aqueous approaches and have become an independent research field. 10 Years ago, when we published our first review on organic reaction pathways in nonaqueous sol–gel approaches, the number of examples was relatively limited. Nowadays, it is almost impossible to provide an exhaustive overview. Here we review the development of the last few years, without neglecting pioneering examples, which help to follow the historical development. The importance of a profound understanding of mechanistic aspects of nanoparticle crystallization and formation mechanisms can't be overestimated, when it comes to the design of rational synthesis concepts under minimization of trial‐and‐error experiments. The main reason for the progress in mechanistic understanding lies in the availability of characterization tools that make it possible to monitor chemical reactions from the dissolution of the precursor to the nucleation and growth of the nanoparticles, by ex situ methods involving sampling after different reaction times, but more and more also by in situ studies. After a short introduction to experimental aspects of nonaqueous sol–gel routes to metal oxide nanoparticles, we provide an overview of the main and basic organic reaction pathways in these approaches. Afterwards, we summarize the main characterization methods to study formation mechanisms, and then we discuss in great depth the chemical formation mechanisms of many different types of metal oxide nanoparticles. The review concludes with a paragraph on selected crystallization mechanisms reported for nonaqueous systems and a few illustrative examples of nonaqueous sol–gel concepts applied to surface chemistry.
Why DNA Is a More Effective Scaffold than RNA in Nucleic Acid‐Based Asymmetric Catalysis—Supramolecular Control of Cooperative Effects
Authors: Marek Jasmin J. , Hennecke Ulrich 
Published: April 2017

AbstractNucleic acids can form efficient hybrid catalysts for asymmetric catalysis upon binding of low‐molecular‐weight metal complexes. Up to now DNA has been the preferred nucleic acid component, while RNA was largely ignored. It is shown that despite RNA′s successful use in ribozymes, RNA is less suited for use in hybrid catalysts for asymmetric catalysis. A common dimethyl bipyridine copper complex does not form highly active and enantioselective hybrid catalysts with RNA due to the absence of synergistic effects between the copper complex and dsRNA.
Simultaneous Triple Imaging with Two PARASHIFT Probes: Encoding Anatomical, pH and Temperature Information using Magnetic Resonance Shift Imaging
Authors: Finney Katie‐Louise N. A. , Harnden Alice C. , Rogers Nicola J. , Senanayake P. Kanthi , Blamire Andrew M. , O'Hogain Dara , Parker David 
Published: April 2017

AbstractThe chemical shift of paramagnetically shifted resonances in lanthanide(III) complexes encodes information about temperature and has also been made to report pH in parallel, through introduction of a single phosphonate group adjacent to the reporter tert‐butyl resonance. The enhanced sensitivity of this new probe has allowed the simultaneous triple imaging of the water signal and the shifted tert‐butyl signals of thulium and dysprosium complexes of a common ligand, separated by over 160 ppm. In parallel spectral imaging experiments, the temperature and pH dependence of the frequency of the Tm and Dy signals has been deconvoluted, allowing the pH and temperature in the liver, kidney and bladder to be measured.
Modulating the Bonding Properties of N‐Heterocyclic Carbenes (NHCs): A Systematic Charge‐Displacement Analysis
Authors: Gaggioli Carlo Alberto , Bistoni Giovanni , Ciancaleoni Gianluca , Tarantelli Francesco , Belpassi Leonardo , Belanzoni Paola 
Published: April 2017

AbstractIn view of their intensive use as ligands in many reactions catalyzed by transition‐metal complexes, modulation of the bonding properties of N‐heterocyclic carbenes (NHCs) on a rational basis is highly desirable, which should enable optimization of current applications or even promote new functions. In this paper, we provide a quantitative analysis of the chemical bond between a metal fragment AuCl and a series of 29 different NHCs in [(NHC)AuCl] complexes. NHCs electronic properties are modified through: i) variation of the groups attached to the NHC nitrogen atoms or backbone; ii) change of unsaturation/size of the NHC ring; iii) inclusion of paracyclophane moieties; or iv) heteroatom substitution on the NHC ring. For evaluating the donation and back‐donation components of the Dewar–Chatt–Duncanson (DCD) model in the NHC−AuCl bond, we apply the charge‐displacement (CD) analysis within the NOCV (natural orbitals for chemical valence) framework, a methodology that avoids the constraint of using symmetrized structures. We show that modulation of the NHC bonding properties requires substantial modification of their structure, such as, for instance, insertion of two ketone groups into the NHC backbone (which enhances the π back‐donation bond component and introduces an effective electronic communication within the NHC ring) or replacement of a nitrogen atom in the ring with an sp3 or sp2 carbon atom (which increases and decreases the π back‐donation bond component, respectively). We extend our investigation by quantitatively comparing the NHC electronic structures for a subset of 13 NHCs in [(NHC)PPh] adducts, the 31P NMR chemical shift values of which are experimentally available. The latter have been considered as a suitable tool for measuring the NHCs π acceptor properties [Bertrand et al., Angew. Chem. Int. Ed. 2013, 52, 2939–2943]. We show that information obtained using the metal fragment can be transferred to the PPh moiety and vice versa. However, the 31P NMR chemical shift values only qualitatively correlate with the π acceptor properties of the NHCs, with the stronger π acidic carbenes as the most outliners.
Building Block Dependent Morphology Modulation of Cage Nanoparticles and Recognition of Nitroaromatics
Authors: Acharyya Koushik , Chowdhury Aniket , Mondal Bijnaneswar , Chakraborty Shubhadip , Mukherjee Partha Sarathi 
Published: April 2017

AbstractMorphology of nanomaterials has a strong impact on their chemical/physical properties, and controlled synthesis of such materials with desirable morphology is a major challenge. This article presents the role of a building block in the morphology of organic cage particles. In this context, three organic cages (A3X2, B3X2, and C3X2) were devised from triphenylamine‐based dialdehydes (A–C) and a flexible triamine (X) by utilizing dynamic imine chemistry. All of the synthesized cages were characterized by various spectroscopic techniques, which suggested the formation of [3+2] assembled architectures. Though the cages are isostructural, structural variation in the aldehyde building blocks imparted by the incorporation of phenyl moieties into the triphenylamine core produces morphologically diverse cage particles, as indicated by SEM. The synthesized cages were found to be fluorescent; the reduced analogue of cage A3X2 (A3X2r) was tested to explore its use as a chemosensor for the detection of nitroaromatic explosives. The experimental findings suggest high selectivity and sensitivity of A3X2r towards picric acid (PA) among the various nitroaromatics tested. A theoretical investigation of fluorescence quenching suggested that formation of a ground‐state charge‐transfer complex with a resonance energy‐transfer (RET) process could be the main reason behind such selectivity of the cage towards PA.
Switching Thin Films of Azobenzene‐Containing Metal–Organic Frameworks with Visible Light
Authors: Müller Kai , Knebel Alexander , Zhao Fangli , Bléger David , Caro Jürgen , Heinke Lars 
Published: April 2017

AbstractStimuli‐responsive molecules change their properties when exposed to external signals, such as light, and enable the preparation of smart materials. UV light, which often destroys organic materials, is typically required for activating the desired response of photoswitchable compounds, significantly limiting the potential applications of light‐operated smart materials. Herein, we present the first metal–organic framework (MOF), which enables reversible modulation of key properties upon irradiation with visible light only. The fluorinated azobenzene side groups in the MOF structure can be reversibly switched between the trans and cis state by green and violet light, avoiding UV light. It was demonstrated that the uptake of guest molecules by these MOF films can be switched in a fully remote‐controlled way. The membrane separation of hydrogen/hydrocarbon mixtures was investigated. The light‐induced changes of the MOF pore size result in the switching of the permeation and of the selection factor.
Rhodium‐Catalyzed Stereospecific C−H Amination for the Construction of Spiroaminal Cores: Reactivity Difference between Nitrenoid and Carbenoid Species against Amide Functionality
Authors: Kono Masato , Harada Shingo , Nemoto Tetsuhiro 
Published: April 2017

AbstractMetal nitrenoids and metal carbenoids exhibit similar reactivity for insertion into a C−H bond and a C=C double bond. These reactions have attracted the attention of organic chemists due to their unusual bond‐forming ability, but the reactivity difference between these chemical species has not been studied. In this paper, we examined the reactivity difference using the corresponding Rh nitrenoid and Rh carbenoid precursors. The Rh nitrenoid inserted into an intramolecular C(sp3)−H bond adjacent to an amide nitrogen, affording functionalized spiroaminals that are ubiquitous in natural products, while the Rh carbenoid inserted into an amide C−N bond. The totally different reactivity was rationalized by the relatively low energy barrier for the C−H insertion reaction of the Rh nitrenoid. Computational analysis suggests that the origin of the discrepancy is the electrophilicity of the coordinating atoms to the Rh complex.
One‐Step Synthesis of MIL‐53(Al)/Boehmite Composites
Authors: Schwegler Johannes , Fischer Marcus , Paula Carolin , Schulz Peter S. , Hartmann Martin 
Published: April 2017

Abstract[EMIM][Hbdc] and [EMIM]2[bdc] were synthesized and successfully used in a one‐step synthesis procedure of MIL‐53(Al)/boehmite composites with unusual properties. The breathing effect typically observed for MIL‐53(Al) is not found and scanning electron microscopy confirms the presence of MIL‐53 nanoparticles in a boehmite matrix. The completely different characteristics of this MIL‐53 samples in comparison to hydrothermally synthesized MIL‐53(Al) clearly demonstrate the tremendous influence of variations of the reagents used for the syntheses of metal‐organic framework materials.
Design of Dividing‐Wall Columns by Mixed‐Integer Nonlinear Programming Optimization
Authors: Franke Meik B. 
Published: April 2017

AbstractDividing‐wall columns (DWCs) offer an interesting alternative to conventional distillation towers. Savings of up to 30 % in both energy and capital cost are reported. While these high savings are realistic in some applications, DWCs offer less or no advantage at all in other applications. In any case, it is important to make a fair comparison between the conventional system and the DWC based on an optimized process design. Mixed‐integer nonlinear programming (MINLP), especially the presented modified Generalized Benders Decomposition approach, could be the tool to make this comparison, as shown here.
Biological Evaluation of Dipyrromethanes in Cancer Cell Lines: Antiproliferative and Pro‐apoptotic Properties
Authors: Jorda Radek , Lopes Susana M. M. , Řezníčková Eva , Kryštof Vladimír , Pinho e Melo Teresa M. V. D. 
Published: April 2017

AbstractFunctionalized dipyrromethanes were synthesized by hetero‐Diels–Alder reactions of nitroso‐ and azoalkenes and screened for their in vitro activity as anticancer agents. The studied dipyrromethanes were tested against leukemia and lymphoma cell lines, and showed GI50 values in the mid‐micromolar range. The pro‐apoptotic activities of two candidates, (E)‐1‐(2′‐ethoxycarbonylhydrazono‐1′‐benzyl‐1H‐tetrazol‐5‐yl)‐5,5′‐diethyldipyrromethane and (E)‐1‐(2′‐p‐nitrophenyl‐2′‐hydroxyiminoethyl)‐5‐phenyldipyrromethane, and their effects on the cell cycle are described. The latter compound was found to decrease the S‐phase cell population in a dose‐dependent manner and to irreversibly block cells in the G2/M phase.
Tumor volume doubling time of pulmonary metastases predicts overall survival and can guide the initiation of multikinase inhibitor therapy in patients with metastatic, follicular cell‐derived thyroid carcinoma
Authors: Sabra Mona M. , Sherman Eric J. , Tuttle R. Michael 
Published: April 2017

BACKGROUNDThe current study was conducted to better characterize the association between overall survival (OS) from metastatic thyroid cancer and the rate of structural disease progression.METHODSIn this retrospective study, the average tumor volume doubling time (midDT) of 2 dominant lung metastases was used to group patients into 6 clinically relevant cohorts. OS was calculated from the time of metastasis diagnosis and from the time the pulmonary lesions crossed over the 1‐cm diameter threshold.RESULTSThe tumor growth rate was remarkably constant in lung metastases from thyroid cancer over a median follow‐up of 8.5 years (median correlation coefficient, 0.92; coefficient of determination, 0.85). Patients with a midDT ≤1 year were found to have worse OS compared with those with a higher midDT (log‐rank P = .01). The 5‐year OS rate from the 1‐cm diameter time point was 20% for patients with a midDT ≤1 year (15 patients), 50% for patients with a midDT of 1 to 2 years (19 patients), 53% for patients with a midDT of 2 to 3 years (9 patients), 80% for patients with a midDT of 3 to 4 years (6 patients), and 80% for patients with a midDT of ≥4 years or who were negative (12 patients). Within the group of patients with a midDT ≤1 year, the 2‐year OS rate from the 1‐cm diameter point was 88% in the patients treated with multikinase inhibitors (8 patients) versus 43% in the nontreated group (7 patients) (P = .13).CONCLUSIONSThe midDT of lung metastases appears to be a good prognostic indicator of OS in patients with metastatic thyroid cancer. Unlike the thyroglobulin DT, the midDT alone can be used to predict eligibility for multikinase inhibitor therapy. Cancer 2017;123:2955–64. © 2017 American Cancer Society.
Effects of patient‐centered communication on anxiety, negative affect, and trust in the physician in delivering a cancer diagnosis: A randomized, experimental study
Authors: Zwingmann Jelena , Baile Walter F. , Schmier Johann W. , Bernhard Jürg , Keller Monika 
Published: April 2017

BACKGROUNDWhen bad news about a cancer diagnosis is being delivered, patient‐centered communication (PCC) has been considered important for patients' adjustment and well‐being. However, few studies have explored how interpersonal skills might help cancer patients cope with anxiety and distress during bad‐news encounters.METHODSA prospective, experimental design was used to investigate the impact of the physician communication style during a bad‐news encounter. Ninety‐eight cancer patients and 92 unaffected subjects of both sexes were randomly assigned to view a video of a clinician delivering a first cancer diagnosis with either an enhanced patient‐centered communication (E‐PCC) style or a low patient‐centered communication (L‐PCC) style. Participants rated state anxiety and negative affect before and immediately after the video exposure, whereas trust in the physician was rated after the video exposure only. Main and interaction effects were analyzed with generalized linear models.RESULTSViewing the disclosure of a cancer diagnosis resulted in a substantial increase in state anxiety and negative affect among all participants. This emotional response was moderated by the physician's communication style: Participants viewing an oncologist displaying an E‐PCC style were significantly less anxious than those watching an oncologist displaying an L‐PCC style. They also reported significantly higher trust in the physician.CONCLUSIONSUnder a threatening, anxiety‐provoking disclosure of bad news, a short sequence of empathic PCC influences subjects' psychological state, insofar that they report feeling less anxious and more trustful of the oncologist. Video exposure appears to be a valuable method for investigating the impact of a physician's communication style during critical encounters. Cancer 2017;123:3167–75. © 2017 American Cancer Society.
The impact of the omission or inadequate dosing of radiotherapy in extranodal natural killer T‐cell lymphoma, nasal type, in the United States
Authors: Vargo John A. , Patel Arisha , Glaser Scott M. , Balasubramani Goundappa K. , Farah Rafic J. , Marks Stanley M. , Beriwal Sushil 
Published: April 2017

BACKGROUNDExtranodal natural killer T‐cell lymphoma, nasal‐type (NKTCL), is a rare malignancy in Western populations and is thus challenging for standardization of care and a prospective study. This study was aimed at defining patterns of care for NKTCL in the context of radiotherapy (RT) use and dose selection in the United States.METHODSSix hundred forty‐two stage I‐II NKTCL patients from 1998 to 2012 were identified from the National Cancer Data Base. Binary logistic regression analyses were performed to identify sociodemographic, treatment, and tumor characteristics predictive of the treatment selection and RT dose. Overall survival (OS) analyses were completed with the Kaplan‐Meier and Cox multivariate methods, including a propensity score adjustment for a potential indication bias.RESULTSOf the 642 included NKTCL patients, 70% were at stage I, 79% were white, and 66% were ≤ 60 years old. Fifty‐five percent received chemotherapy plus RT, 19% received RT alone, and 27% received chemotherapy alone. The median RT dose was 50 Gy (interquartile range, 43.2‐54 Gy), 37% received < 45 Gy, and 43% received < 50 Gy. A multivariate survival analysis showed improved OS in comparison with chemotherapy alone for RT alone at ≥50 Gy (hazard ratio [HR], 0.41; 95% confidence interval [CI], 0.23‐0.70; P < .01), for chemotherapy plus RT at <50 Gy (HR, 0.55, 95% CI, 0.36‐0.86; P < .01), and for chemotherapy plus RT at ≥50 Gy (HR, 0.41; 95% CI, 0.27‐0.63; P < .01).CONCLUSIONSStage I‐II NKTCL patients in the United States commonly receive chemotherapy alone or suboptimal‐dose RT. The omission of RT or the use of suboptimal RT is negatively associated with OS. Efforts to continue improving evidenced‐based management are warranted. Cancer 2017;123:3176–85. © 2017 American Cancer Society.
p16/Ki‐67 dual labeling and urinary cytology results according to the New Paris System for Reporting Urinary Cytology: Impact of extended follow‐up
Authors: Piaton Eric , Advenier Anne‐Sophie , Carré Christian , Decaussin‐Petrucci Myriam , Mège‐Lechevallier Florence , Hutin Karine , Nennig Cindy , Colombel Marc , Ruffion Alain 
Published: April 2017

BACKGROUNDOverexpression of p16INK4a has been identified in urothelial malignancies both cytologically and histologically. In addition, p16/Ki‐67 dual labeling has been shown to identify high‐grade urothelial cancer cells and some progression cases within a 12‐month delay. The Paris System for Reporting Urinary Cytology (TPS) was published in late 2015. Its aim is to clarify the criteria for diagnosing or, conversely, excluding high‐grade urothelial carcinoma (HGUC).METHODSDual labeling was performed on archived ThinPrep‐based Papanicolaou slides. A total of 208 samples (negative for high‐grade urothelial carcinoma [NHGUC], 59; consistent with low‐grade urothelial neoplasia [LGUN], 24; atypical urothelial cells [AUC], 15; and suspicious for or showing HGUC, 110) were analyzed for p16/Ki‐67 after reclassification according to TPS. We assessed the oncologic status of the patients with cystoscopy, urinary cytology, histology, and prolonged 36‐month follow‐up data.RESULTSThe sensitivity of p16/Ki‐67 for life‐threatening lesions was not different from that of urinary cytology (82.8% vs 83.6%; P = 1). However, among patients with samples classified as NHGUC and AUC, disease‐free survival was significantly shorter for dual‐labeled cases versus cases with negative dual labeling (P < .0001). The same tendency was observed in patients with histologically proven LGUN (P < .0001). As for specificity in patients with negative cystoscopy and cytology combined, prolonged follow‐up showed 90% overall survival at 24 months.CONCLUSIONSA long‐term evaluation of p16/Ki‐67 dual labeling may identify HGUC and progression in cases with negative/low‐grade urinary cytology results, and there are potential implications for the clinical management of patients after the conservative treatment of non–muscle‐invasive urothelial carcinoma. Cancer Cytopathol 2017;125:552–62. © 2017 American Cancer Society.
Fluorescent Proteins for Flow Cytometry
Authors: Hawley Teresa S. , Hawley Robert G. , Telford William G. 
Published: April 2017

AbstractFluorescent proteins have become standard tools for cell and molecular biologists. The color palette of fluorescent proteins spans the ultraviolet, visible, and near‐infrared spectrum. Utility of fluorescent proteins has been greatly facilitated by the availability of compact and affordable solid state lasers capable of providing various excitation wavelengths. In theory, the plethora of fluorescent proteins and lasers make it easy to detect multiple fluorescent proteins simultaneously. However, in practice, heavy spectral overlap due to broad excitation and emission spectra presents a challenge. In conventional flow cytometry, careful selection of excitation wavelengths and detection filters is necessary. Spectral flow cytometry, an emerging methodology that is not confined by the “one color, one detector” paradigm, shows promise in the facile detection of multiple fluorescent proteins. This chapter provides a synopsis of fluorescent protein development, a list of commonly used fluorescent proteins, some practical considerations and strategies for detection, and examples of applications. © 2017 by John Wiley & Sons, Inc.
High‐Throughput Particle Uptake Analysis by Imaging Flow Cytometry
Authors: Smirnov Asya , Solga Michael D. , Lannigan Joanne , Criss Alison K. 
Published: April 2017

AbstractQuantifying the efficiency of particle uptake by host cells is important in the fields of infectious diseases, autoimmunity, cancer, developmental biology, and drug delivery. Here we present a protocol for high‐throughput analysis of particle uptake by imaging flow cytometry, using the bacterium Neisseria gonorrhoeae attached to and internalized by neutrophils as an example. Cells are exposed to fluorescently labeled bacteria, fixed, and stained with a bacteria‐specific antibody of a different fluorophore. Thus, in the absence of a permeabilizing agent, extracellular bacteria are double‐labeled with two fluorophores while intracellular bacteria remain single‐labeled. A spot count algorithm is used to determine the number of single‐ and double‐labeled bacteria in individual cells, to calculate the percent of cells associated with bacteria, percent of cells with internalized bacteria, and percent of cell‐associated bacteria that are internalized. These analyses quantify bacterial association and internalization across thousands of cells and can be applied to diverse experimental systems. © 2017 by John Wiley & Sons, Inc.