bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anschauliche Bezeichnungen der Chemie von Metallocen‐Komplexen der Gruppe 4
Authors: Rosenthal Uwe 
Published: August 2020

AbstractDrei Beispiele für die Verwendung einfacher und anschaulicher Benennungen in der Organometallchemie von Metallocen‐Komplexen der Gruppe 4 werden erklärt und diskutiert. Die Bezeichnung “tuck(ed)‐in” betrifft das Verhalten des Decamethyltitanocens [(C5Me5)2Ti] oder ähnlicher Komplexe, bei dem eine oder zwei Methylgruppen Titanhydrid‐Komplexe wie [(C5Me5)(C5Me4CH2)TiH] oder andere Hydridkomplexe durch C‐H‐Aktivierung bilden. In der “merry‐go‐round‐reaction” wird die Umlagerung von C‐Atomen am Titan in Organometallmolekülen beschrieben, bei der eine Rotation von zwei C‐Atomen mit einer Rotation der sechsgliedrigen Dihydroindenyl‐Einheit am Titan erfolgt. Das dritte Beispiel “migration” oder “tobogganing” betrifft das “sliding” von Titanocen an der Kette eines linearen Polyins durch Koordinierung von einer oder mehreren Dreifachbindungen. In allen diesen Reaktionen wechselt die Koordinationsweise des Metalls am Cp‐ oder dem Substratliganden, was mit einer intramolekularen Dynamik verbunden ist.
How Big is the Pinacol Boronic Ester as a Substituent?
Authors: Fasano Valerio , McFord Aidan W. , Butts Craig P. , Collins Beatrice S. L. , Fey Natalie , Alder Roger W. , Aggarwal Varinder K. 
Published: August 2020

AbstractThe synthetically versatile pinacol boronic ester group (Bpin) is generally thought of as a bulky moiety because of the two adjacent quaternary sp3‐hydribized carbon atoms in its diol backbone. However, recent diastereoselective reactions reported in the literature have cast doubt on this perception. Reported herein is a detailed experimental and computational analysis of Bpin and structurally related boronic esters which allows determination of three different steric parameters for the Bpin group: the A‐value, ligand cone angle, and percent buried volume. All three parameters suggest that the Bpin moiety is remarkably small, with the planarity of the oxygen‐boron‐oxygen motif playing an important role in minimising steric interactions. Of the three steric parameters, percent buried volume provides the best correlation between steric size and diastereoselectivity in a Diels–Alder reaction.
Aptamer‐Mediated Reversible Transactivation of Gene Expression by Light
Authors: Renzl Christian , Kakoti Ankana , Mayer Günter 
Published: August 2020

AbstractThe investigation and manipulation of cellular processes with subcellular resolution requires non‐invasive tools with spatiotemporal precision and reversibility. Building on the interaction of the photoreceptor PAL with an RNA aptamer, we describe a variation of the CRISPR/dCAS9 system for light‐controlled activation of gene expression. This platform significantly reduces the coding space required for genetic manipulation and provides a strong on‐switch with almost no residual activity in the dark. It adds to the current set of modular building blocks for synthetic biological circuit design and is broadly applicable.
Synthesis of 2D Germanane (GeH): a New, Fast, and Facile Approach
Authors: Giousis Theodosis , Potsi Georgia , Kouloumpis Antonios , Spyrou Konstantinos , Georgantas Yiannis , Chalmpes Nikolaos , Dimos Konstantinos , Antoniou Myrsini‐Kiriaki , Papavassiliou Georgios , Bourlinos Athanasios B. , Kim Hae Jin , Wadi Vijay Kumar Shankarayya , Alhassan Saeed , Ahmadi Majid , Kooi Bart J. , Blake Graeme , Balazs Daniel M. , Loi Maria A. , Gournis Dimitrios , Rudolf Petra 
Published: August 2020

AbstractGermanane (GeH), a germanium analogue of graphane, has recently attracted considerable interest because its remarkable combination of properties makes it an extremely suitable candidate to be used as 2D material for field effect devices, photovoltaics, and photocatalysis. Up to now, the synthesis of GeH has been conducted by substituting Ca by H in a β‐CaGe2 layered Zintl phase through topochemical deintercalation in aqueous HCl. This reaction is generally slow and takes place over 6 to 14 days. The new and facile protocol presented here allows to synthesize GeH at room temperature in a significantly shorter time (a few minutes), which renders this method highly attractive for technological applications. The GeH produced with this method is highly pure and has a band gap (Eg) close to 1.4 eV, a lower value than that reported for germanane synthesized using HCl, which is promising for incorporation of GeH in solar cells.
A Fully Non‐fused Ring Acceptor with Planar Backbone and Near‐IR Absorption for High Performance Polymer Solar Cells
Authors: Chen Ya‐Nan , Li Miao , Wang Yunzhi , Wang Jing , Zhang Ming , Zhou Yuanyuan , Yang Jianming , Liu Yahui , Liu Feng , Tang Zheng , Bao Qinye , Bo Zhishan 
Published: August 2020

AbstractFused‐ring electron acceptors have made significant progress in recent years, while the development of fully non‐fused ring acceptors has been unsatisfactory. Here, two fully non‐fused ring acceptors, o‐4TBC‐2F and m‐4TBC‐2F, were designed and synthesized. By regulating the location of the hexyloxy chains, o‐4TBC‐2F formed planar backbones, while m‐4TBC‐2F displayed a twisted backbone. Additionally, the o‐4TBC‐2F film showed a markedly red‐shifted absorption after thermal annealing, which indicated the formation of J‐aggregates. For fabrication of organic solar cells (OSCs), PBDB‐T was used as a donor and blended with the two acceptors. The o‐4TBC‐2F‐based blend films displayed higher charge mobilities, lower energy loss and a higher power conversion efficiency (PCE). The optimized devices based on o‐4TBC‐2F gave a PCE of 10.26 %, which was much higher than those based on m‐4TBC‐2F at 2.63 %, and it is one of the highest reported PCE values for fully non‐fused ring electron acceptors.
Cross‐Module Enoylreduction in the Azalomycin F Polyketide Synthase
Authors: Zhai Guifa , Wang Wenyan , Xu Wei , Sun Guo , Hu Chaoqun , Wu Xiangming , Cong Zisong , Deng Liang , Shi Yanrong , Leadlay Peter F. , Song Heng , Hong Kui , Deng Zixin , Sun Yuhui 
Published: August 2020

AbstractThe colinearity of canonical modular polyketide synthases, which creates a direct link between multienzyme structure and the chemical structure of the biosynthetic end‐product, has become a cornerstone of knowledge‐based genome mining. Herein, we report genetic and enzymatic evidence for the remarkable role of an enoylreductase in the polyketide synthase for azalomycin F biosynthesis. This internal enoylreductase domain, previously identified as acting only in the second of two chain extension cycles on an initial iterative module, is shown to also catalyze enoylreduction in trans within the next module. The mechanism for this rare deviation from colinearity appears to involve direct cross‐modular interaction of the reductase with the longer acyl chain, rather than back transfer of the substrate into the iterative module, suggesting an additional and surprising plasticity in natural PKS assembly‐line catalysis.
Vivid Wording for the Chemistry of Group 4 Metallocene Complexes
Authors: Rosenthal Uwe 
Published: August 2020

AbstractThree selected examples for the use of unusual wording to describe the organometallic chemistry of Group 4 metallocenes are explained and discussed. The term “tuck(ed)‐in” concerns the behavior of decamethyltitanocene [(C5Me5)2Ti] and similar complexes in which one or two methyl groups form the titanium hydride complex [(C5Me5)(C5Me4CH2)TiH] or other hydride complexes by C−H activation. In the so‐called “merry‐go‐round reaction” the rearrangement of C atoms bound to titanium in organometallic molecules is described which corresponds to the rotation of two C atoms along with a rotation of the six‐membered ring in a dihydroindenyl moiety at titanium. In the third example “migration” or “tobogganing” concerns the “sliding” of titanocene along the chain of a linear polyyne by coordination to one or more triple bonds. In all these reactions changes of the coordination mode of the metal at Cp or substrate ligands by intramolecular dynamics occur.
Visible‐Light‐Induced Cysteine‐Specific Bioconjugation: Biocompatible Thiol–Ene Click Chemistry
Authors: Choi Hangyeol , Kim Myojeong , Jang Jaebong , Hong Sungwoo 
Published: August 2020

AbstractBioconjugation methods using visible‐light photocatalysis have emerged as powerful synthetic tools for the selective modification of biomolecules under mild reaction conditions. However, the number of photochemical transformations that allow successful protein bioconjugation is still limited because of the need for stringent reaction conditions. Herein, we report that a newly developed water‐compatible fluorescent photosensitizer QPEG can be used for visible‐light‐induced cysteine‐specific bioconjugation for the installation of QPEG by exploiting its intrinsic photosensitizing ability to activate the S−H bond of cysteine. The slightly modified QCAT enables the effective photocatalytic cysteine‐specific conjugation of biologically relevant groups. The superior reactivity and cysteine selectivity of this methodology was further corroborated by traceless bioconjugation with a series of complex peptides and proteins under biocompatible conditions.
Directed Reaction Engineering Boosts Succinate Formation of Synechocystis sp. PCC 6803_Δsll1625
Authors: Mock Magdalena , Schmid Andreas , Bühler Katja 
Published: August 2020

AbstractIt is known that Synechocystis sp. PCC 6803 carrying a partial deletion of the succinate dehydrogenase (Synechocystis_∆sll1625) secretes succinate during aerobic cultivation with continuous illumination and in the presence of CO2. Maximal succinate titers of 2 mM (236 mg L−1) are reported. CO2 is identified as a crucial parameter for product formation, however, a detailed characterization of different cultivation conditions is still missing. Here the focus is on further reaction engineering to improve the photoautotrophic production of succinate using Synechocystis_∆sll1625. Therefore the impact of light availability, illumination regimes, nutrient availability, and external pH on product formation are investigated. Results obtained in this study reveal the importance of these parameters on the formation of succinate and cultivation with light/dark cycles increases the succinate concentration to 3 mM (354 mg L−1) after 28 days of cultivation. Furthermore, cultivation in unbuffered medium under ambient CO2 conditions even doubled the final succinate titer to 4 mM (472 mg L−1) after 28 days. Taking biomass concentrations into account, a maximal yield of succinate on biomass of 215 mgSucc gCDW−1 is achieved, which is the highest so far reported for the production of succinate utilizing Synechocystis as host organism.
Assessing value chain interventions in Zambian and Ethiopian forest beekeeping systems
Authors: Meaton Julia , Lowore Janet , Wood Adrian 
Published: August 2020

AbstractThis paper explores the value chains of forest honey in Zambia and Ethiopia and considers a range of interventions that might deliver livelihood opportunities for forest based communities while simultaneously promoting forest conservation. Seven types of interventions are identified including those focused on rights, technological developments, gender issues, product quality, trade development, product processing and added value, such as fair trade certification. The paper draws on evidence provided by forest beekeeper stakeholders in the Mwinilunga area in Zambia, and from evidence of an action research project in South West Ethiopia. The paper finds that many common value chain interventions are inappropriate, with the so called “modernisation” of the activity particularly problematic. The paper concludes that traditional forest beekeeping practices should be encouraged, and only carefully considered interventions around quality and marketing should be considered as these support a sustainable honey economy that delivers both livelihood gains and forest maintenance.
A specific microRNA profile as predictive biomarker for systemic treatment in patients with metastatic colorectal cancer
Authors: Poel Dennis , Gootjes Elske C. , Bakkerus Lotte , Trypsteen Wim , Dekker Henk , van der Vliet Hans J. , van Grieken Nicole C. T. , Verhoef Cornelis , Buffart Tineke E. , Verheul Henk M. W. 
Published: August 2020

AbstractBackgroundPalliative systemic therapy is currently standard of care for patients with extensive metastatic colorectal cancer (mCRC). A biomarker predicting chemotherapy benefit which prevents toxicity from ineffective treatment is urgently needed. Therefore, a previously developed tissue‐derived microRNA profile to predict clinical benefit from chemotherapy was evaluated in tissue biopsies and serum from patients with mCRC.MethodsSamples were prospectively collected from patients (N = 132) who were treated with capecitabine or 5‐FU/LV with oxaliplatin ± bevacizumab. Response evaluation was performed according to RECIST 1.1 after three or four cycles, respectively. Baseline tissue and serum miRNAs expression levels of miR‐17‐5p, miR‐20a‐5p, miR‐30a‐5p, miR‐92a‐3p, miR‐92b‐3p, and miR‐98‐5p were quantified with RT‐qPCR and droplet digital PCR, respectively. Combined predictive performance of selected variables was tested using logistic regression analysis.ResultsFrom 132 patients, 81 fresh frozen tissue biopsies from metastases and 93 serum samples were available. Based on expression levels of miRNAs in tissue, progressive disease could be predicted with an AUC of 0.85 (95% CI:0.72‐0.91) and response could be predicted with an AUC of 0.70 (95% CI:0.56‐0.80). This did not outperform clinical parameters alone (respectively P = .14 and P = .27). Expression levels of miR‐92a‐3p and miR‐98‐5p in serum significantly improved the predictive value of clinical parameters for response to chemotherapy (AUC 0.74, 95% CI:0.64‐0.84, P = .003) in this cohort.ConclusionsThe additive predictive value to clinical parameters of the tissue‐derived six miRNA profile for clinical benefit could not be validated in patients with mCRC treated with first‐line systemic therapy. Although miR‐92a‐3p and miR‐98‐5p serum levels improved the predictive value of clinical parameters, it remained insufficient for clinical decision‐making.
Nucleosomes and Epigenetics from a Chemical Perspective
Authors: Feng Yihong , Endo Masayuki , Sugiyama Hiroshi 
Published: August 2020

AbstractNucleosomes, which are the fundamental building blocks of chromatin, are highly dynamic, they play vital roles in the formation of higher‐order chromatin structures and orchestrate gene regulation. Nucleosome structures, histone modifications, nucleosome‐binding proteins, and their functions are being gradually unravelled with the development of epigenetics. With the continuous development of research approaches such as cryo‐EM, FRET and next‐generation sequencing for genome‐wide analysis of nucleosomes, the understanding of nucleosomes is getting wider and deeper. Herein, we review recent progress in research on nucleosomes and epigenetics, from nucleosome structure to chromatin formation, with a focus on chemical aspects. Basic knowledge of the nucleosome (nucleosome structure, nucleosome position sequence, nucleosome assembly and remodeling), epigenetic modifications, chromatin structure, chemical biology methods and nucleosome, observation nucleosome by AFM, phase separation and nucleosomes are described in this review.
Multivalent, Stabilized Mannose‐6‐Phosphates for the Targeted Delivery of Toll‐Like Receptor Ligands and Peptide Antigens
Authors: Reintjens Niels R. M. , Tondini Elena , Vis Christopher , McGlinn Toroa , Meeuwenoord Nico J. , Hogervorst Tim P. , Overkleeft Herman S. , Filippov Dmitri V. , van der Marel Gijsbert A. , Ossendorp Ferry , Codée Jeroen D. C. 
Published: August 2020

AbstractMannose‐6‐phosphate (M6P) is recognized by the mannose‐6‐phosphate receptor and plays an important role in the transport of cargo to the endosomes, making it an attractive tool to improve endosomal trafficking of vaccines. We describe herein the assembly of peptide antigen conjugates carrying clusters of mannose‐6‐C‐phosphonates (M6Po). The M6Po's are stable M6P mimics that are resistant to cleavage of the phosphate group by endogenous phosphatases. Two different strategies for the incorporation of the M6Po clusters in the conjugate have been developed: the first relies on a “post‐assembly” click approach employing an M6Po bearing an alkyne functionality; the second hinges on an M6Po C‐glycoside amino acid building block that can be used in solid‐phase peptide synthesis. The generated conjugates were further equipped with a TLR7 ligand to stimulate dendritic cell (DC) maturation. While antigen presentation is hindered by the presence of the M6Po clusters, the incorporation of the M6Po clusters leads to increased activation of DCs, thus demonstrating their potential in improving vaccine adjuvanticity by intraendosomally active TLR ligands.
4‐Thiouridine‐Enhanced Peroxidase‐Generated Biotinylation of RNA
Authors: Huang Jinguo , Zhao Ruiqi , Qin Shanshan , Yang Shixi , Li Wei , Mo Jing , Wang Fang , Du Yuhao , Weng Xiaocheng , Zhou Xiang 
Published: August 2020

AbstractPeroxidase‐generated proximity labeling is in widespread use to study subcellular proteomes and the protein interaction networks in living cells, but the development of subcellular RNA labeling is limited. APEX‐seq has emerged as a new method to study subcellular RNA in living cells, but the labeling of RNA still has room to improve. In this work, we describe 4‐thiouridine (s4U)‐enhanced peroxidase‐generated biotinylation of RNA with high efficiency. The incorporation of s4U could introduce additional sites for RNA labeling, enhanced biotinylation was observed on monomer, model oligo RNA and total RNA. Through the s4U metabolic approach, the in vivo RNA biotinylation efficiency by peroxidase catalysis was also dramatically increased, which will benefit RNA isolation and study for the spatial transcriptome.
Bullous pemphigoid associated with dipeptidyl peptidase‐4 inhibitor showing unfavorable outcomes despite immediate discontinuation of medication
Authors: Shinohara Yasutake , Iijima Toshie , Sakurai Shintaro , Jojima Teruo , Ohira Eriko , Hayashi Shujiro , Usui Isao , Igawa Ken , Aso Yoshimasa 
Published: August 2020

AbstractWe experienced two cases of dipeptidyl peptidase‐4 (DPP‐4) inhibitor‐associated bullous pemphigoid (BP) showing an unfavorable course despite its discontinuation. Clinicians should carefully monitor the course of DPP‐4 inhibitor‐associated BP even after withdrawal of DPP‐4 inhibitor therapy, especially in very elderly patients.
Extensive amyloid deposits in bone marrow aspirate smears
Authors: Li Ting Hon Stanford , Wong Kit Fai , Wong Wai Shan 
Published: August 2020

AbstractAmyloid light‐chain (AL) amyloidosis is the most common form of systemic amyloidosis. It can cause progressive organ dysfunction and eventually death, mainly due to cardiac involvement. Amyloidosis may rarely present as extensive amorphous, purplish‐blue deposits in marrow aspirate smears. Demonstration of congophilic property and apple‐green birefringence under polarized light in aspirate smears can allow a rapid diagnosis of amyloidosis.
Brief action planning targeting prognostic factors for an adult with persistent low back pain without radiculopathy: A case report
Authors: Connell Gaelan , Verville Leslie , Cancelliere Carol , Wong Jessica J. , Yu Hainan , Shearer Heather M. 
Published: August 2020

AbstractWe describe the implementation of brief action planning in conjunction with evidence‐based clinical practice guideline recommendations to improve self‐efficacy in a patient with psychosocial barriers and persistent nonspecific low back pain.
Luminescent Bimetallic IrIII/AuI Peptide Bioconjugates as Potential Theranostic Agents
Authors: Luengo Andrés , Marzo Isabel , Reback Matthew , Daubit Isabelle M. , Fernández‐Moreira Vanesa , Metzler‐Nolte Nils , Gimeno M. Concepción 
Published: August 2020

AbstractInvited for the cover of this issue are Vanesa Fernández‐Moreira, Nils Metzler‐Nolte, M. Concepción Gimeno and co‐workers at Universidad de Zaragoza and Ruhr‐Universität Bochum. The image depicts the reported bimetallic bioconjugates as planes directing the gold fragment towards the target (lysosomes). Read the full text of the article at 10.1002/chem.202002067.
Hydrogen‐Bond Structure and Low‐Frequency Dynamics of Electrolyte Solutions: Hydration Numbers from ab Initio Water Reorientation Dynamics and Dielectric Relaxation Spectroscopy
Authors: Kim Seonmyeong , Wang Xiangwen , Jang Jeongmin , Eom Kihoon , Clegg Simon L. , Park Gun‐Sik , Di Tommaso Devis 
Published: August 2020

AbstractWe present an atomistic simulation scheme for the determination of the hydration number (h) of aqueous electrolyte solutions based on the calculation of the water dipole reorientation dynamics. In this methodology, the time evolution of an aqueous electrolyte solution generated from ab initio molecular dynamics simulations is used to compute the reorientation time of different water subpopulations. The value of h is determined by considering whether the reorientation time of the water subpopulations is retarded with respect to bulk‐like behavior. The application of this computational protocol to magnesium chloride (MgCl2) solutions at different concentrations (0.6–2.8 mol kg−1) gives h values in excellent agreement with experimental hydration numbers obtained using GHz‐to‐THz dielectric relaxation spectroscopy. This methodology is attractive because it is based on a well‐defined criterion for the definition of hydration number and provides a link with the molecular‐level processes responsible for affecting bulk solution behavior. Analysis of the ab initio molecular dynamics trajectories using radial distribution functions, hydrogen bonding statistics, vibrational density of states, water‐water hydrogen bonding lifetimes, and water dipole reorientation reveals that MgCl2 has a considerable influence on the hydrogen bond network compared with bulk water. These effects have been assigned to the specific strong Mg‐water interaction rather than the Cl‐water interaction.
Identification of Appropriate Endogenous Biomarker for Risk Assessment of Multidrug and Toxin Extrusion Protein‐Mediated Drug‐Drug Interactions in Healthy Volunteers
Authors: Miyake Takeshi , Kimoto Emi , Luo Lina , Mathialagan Sumathy , Horlbogen Lauren M. , Ramanathan Ragu , Wood Linda S. , Johnson Jillian G. , Le Vu H. , Vourvahis Manoli , Rodrigues A. David , Muto Chieko , Furihata Kenichi , Sugiyama Yuichi , Kusuhara Hiroyuki 
Published: August 2020

Endogenous biomarkers are emerging to advance clinical drug‐drug interaction (DDI) risk assessment in drug development. Twelve healthy subjects received a multidrug and toxin exclusion protein (MATE) inhibitor (pyrimethamine, 10, 25, and 75 mg) in a crossover fashion to identify an appropriate endogenous biomarker to assess MATE1/2‐K‐mediated DDI in the kidneys. Metformin (500 mg) was also given as reference probe drug for MATE1/2‐K. In addition to the previously reported endogenous biomarker candidates (creatinine and N1‐methylnicotinamide (1‐NMN)), N1‐methyladenosine (m1A) was included as novel biomarkers. 1‐NMN and m1A presented as superior MATE1/2‐K biomarkers since changes in their renal clearance (CLr) along with pyrimethamine dose were well‐correlated with metformin CLr changes. The CLr of creatinine was reduced by pyrimethamine, however, its changes poorly correlated with metformin CLr changes. Nonlinear regression analysis (CLr vs. mean total concentration of pyrimethamine in plasma) yielded an estimate of the inhibition constant (Ki) of pyrimethamine and the fraction of the clearance pathway sensitive to pyrimethamine. The in vivo Ki value thus obtained was further converted to unbound Ki using plasma unbound fraction of pyrimethamine, which was comparable to the in vitro Ki for MATE1 (1‐NMN) and MATE2‐K (1‐NMN and m1A). It is concluded that 1‐NMN and m1A CLr can be leveraged as quantitative MATE1/2‐K biomarkers for DDI risk assessment in healthy volunteers.