bluuebunny/crossref_metadata_2025_split huggingface dataset:
Organic Acid to Nitrile: A Chemoenzymatic Three‐Step Route
Authors: Winkler Margit , Horvat Melissa , Schiefer Astrid , Weilch Victoria , Rudroff Florian , Pátek Miroslav , Martínková Ludmila 
Published: December 2022

AbstractVarious widely applied compounds contain cyano‐groups, and this functional group serves as a chemical handle for a whole range of different reactions. We report a cyanide free chemoenzymatic cascade for nitrile synthesis. The reaction pathway starts with a reduction of carboxylic acid to aldehyde by carboxylate reductase enzymes (CARs) applied as living cell biocatalysts. The second – chemical – step includes in situ oxime formation with hydroxylamine. The final direct step from oxime to nitrile is catalyzed by aldoxime dehydratases (Oxds). With compatible combinations of a CAR and an Oxd, applied in one‐pot two‐step reactions, several aliphatic and aryl‐aliphatic target nitriles were obtained in more than 80% conversion. Phenylacetonitrile, for example, was prepared in 78% isolated yield. This chemoenzymatic route does not require cyanide salts, toxic metals, or undesired oxidants in contrast to entirely chemical procedures.magnified image
Mn‐Mediated Radical Cascade Cyclization of 1,6‐Enynes with Arylboronic Acids to Access Dihydrobenzo[b]fluorenones
Authors: Raji Reddy Chada , Chandrakant Kajare Roshan , Punna Nagender 
Published: December 2022

AbstractHerein, we report the synthesis of functionalized dihydro‐benzo[b]fluorenones through a manganese‐mediated cascade radical cyclization ofβ‐alkynyl propenones [1,6‐enynes] with arylboronic acids. In the present strategy, the in‐situ generated aryl radical undergoes chemo‐selective addition followed by 5‐exo‐trigcyclization. The reaction is emphasized by high atom‐ and step‐economy with the construction of three new C−C bonds to access the dihydrobenzo[b]fluorenones in 68–81% yield under mild reaction conditions. The synthetic efficacy of the developed method is evidenced by the construction of new C−C and C−N bonds.magnified image
Recent Advance in Transition Metal‐Catalyzed Carboxylic Acid Guided B−H Functionalization of Carboranes
Authors: Wang Qian , Liu Bifu , Feng Kejun , Hashmi A. Stephen K. 
Published: December 2022

AbstractCarboranes, a three‐dimensional class of carbon‐boron molecular clusters with remarkable electronic, physical, chemical characteristics, have proved as useful building blocks in boron neutron capture therapy agents, supramolecular design, optoelectronics, nanomaterials and organometallic/coordination chemistry. Thus, various organic modifications of the B−H and C−H functionalities in carboranes have been developed. These methods with great success utilize directing groups, such as carboxylic acids, to achieve a selective B−H functionalization of carboranes. The carboxyl group can be easily introduced to carboranes and then be removed after reactions. On the other hand, assisted by the carboxyl group a highly regioselective electrophilic attack at the electron‐rich positions B(4) and B(5) of the cage generates five‐membered metallacyclic intermediates, which then undergo further transformation. In this review, we show that transition metal‐catalyzed decarboxylation cross coupling reactions offer an opportunity for the selective and direct B−H activation of carboranes.magnified image
PPDPF Promotes the Development of Mutant KRAS‐Driven Pancreatic Ductal Adenocarcinoma by Regulating the GEF Activity of SOS1
Authors: Ni Qian‐Zhi , Zhu Bing , Ji Yan , Zheng Qian‐Wen , Liang Xin , Ma Ning , Jiang Hao , Zhang Feng‐Kun , Shang Yu‐Rong , Wang Yi‐Kang , Xu Sheng , Zhang Er‐Bin , Yuan Yan‐Mei , Chen Tian‐Wei , Yin Fen‐Fen , Cao Hui‐Jun , Huang Jing‐Yi , Xia Ji , Ding Xu‐Fen , Qiu Xiao‐Song , Ding Kai , Song Chao , Zhou Wen‐Tao , Wu Meng , Wang Kang , Lui Rui , Lin Qiu , Chen Wei , Li Zhi‐Gang , Cheng Shu‐Qun , Wang Xiao‐Fan , Xie Dong , Li Jing‐Jing 
Published: December 2022

AbstractThe guanine nucleotide exchange factor (GEF)
SOS1 catalyzes the exchange of GDP for GTP on RAS. However, regulation of the GEF activity remains elusive. Here, the authors report that PPDPF functions as an important regulator of SOS1. The expression of PPDPF is significantly increased in pancreatic ductal adenocarcinoma (PDAC), associated with poor prognosis and recurrence of PDAC patients. Overexpression of PPDPF promotes PDAC cell growth in vitro and in vivo, while PPDPF knockout exerts opposite effects. Pancreatic‐specific deletion of PPDPF profoundly inhibits tumor development in KRASG12D‐driven genetic mouse models of PDAC. PPDPF can bind GTP and transfer GTP to SOS1. Mutations of the GTP‐binding sites severely impair the tumor‐promoting effect of PPDPF. Consistently, mutations of the critical amino acids mediating SOS1–PPDPF interaction significantly impair the GEF activity of SOS1. Therefore, this study demonstrates a novel model of KRAS activation via PPDPF‐SOS1 axis, and provides a promising therapeutic target for PDAC.
Lipid‐Peptide‐mRNA Nanoparticles Augment Radioiodine Uptake in Anaplastic Thyroid Cancer
Authors: Li Qinglin , Zhang Lizhuo , Lang Jiayan , Tan Zhuo , Feng Qingqing , Zhu Fei , Liu Guangna , Ying Zhangguo , Yu Xuefei , Feng He , Yi Heqing , Wen Qingliang , Jin Tiefeng , Cheng Keman , Zhao Xiao , Ge Minghua 
Published: December 2022

AbstractRestoring sodium iodide symporter (NIS) expression and function remains a major challenge for radioiodine therapy in anaplastic thyroid cancer (ATC). For more efficient delivery of messenger RNA (mRNA) to manipulate protein expression, a lipid‐peptide‐mRNA (LPm) nanoparticle (NP) is developed. The LPm NP is prepared by using amphiphilic peptides to assemble a peptide core and which is then coated with cationic lipids. An amphiphilic chimeric peptide, consisting of nine arginine and hydrophobic segments (6 histidine, C18 or cholesterol), is synthesized for adsorption of mRNA encoding NIS in RNase‐free conditions. In vitro studies show that LP(R9H6) m NP is most efficient at delivering mRNA and can increase NIS expression in ATC cells by more than 10‐fold. After intratumoral injection of NIS mRNA formulated in optimized LPm NP, NIS expression in subcutaneous ATC tumor tissue increases significantly in nude mice, resulting in more iodine 131 (131I) accumulation in the tumor, thereby significantly inhibiting tumor growth. Overall, this work designs three arginine‐rich peptide nanoparticles, contributing to the choice of liposome cores for gene delivery. LPm NP can serve as a promising adjunctive therapy for patients with ATC by restoring iodine affinity and enhancing the therapeutic efficacy of radioactive iodine.
Anion‐Dependent Polarization and Piezoelectric Power Generation in Hybrid Halide MAPbX3 (X = I, Br, and Cl) Thin Films with Out‐of‐Plane Structural Adjustments
Authors: Kim Da Bin , Jo Kyeong Su , Park Kwan Sik , Cho Yong Soo 
Published: December 2022

AbstractAnion‐dependent differences in the electromechanical energy harvesting capability of perovskite halides have not been experimentally demonstrated thus far. Herein, anion‐dependent piezoelectricity and bending‐driven power generation in high‐quality methylammonium lead halide MAPbX3 (X = I, Br, and Cl) thin films are explored; additionally, anisotropic in situ strain is imposed to improve energy harvesting under tensile bending. After applying the maximum in situ strain of −0.73% for all the halide thin films, the MAPbI3 thin‐film harvester exhibited a peak voltage/current of ≈23.1 V/≈1703 nA as the best values, whereas MAPbBr3 and MAPbCl3 demonstrated ≈5.6 V/≈176 nA and ≈3.3 V/≈141 nA, respectively, under identical bending conditions. Apart from apparent ferroelectricity of tetragonal MAPbI3, origin of the piezoelectricity in both cubic MAPbBr3 and MAPbCl3 is explored as being related to organic–inorganic hydrogen bonding, lattice distortion, and ionic migration, with experimental supports of effective piezoelectric coefficient and grain boundary potential. Conclusively, piezoelectricity of the cubic halides is assumed to be due to their soft polarity modes and relatively low elastic modulus with vacancies contributing to space‐charge polarization. In the case of ferroelectric MAPbI3, the distortion of PbI6 octahedra and atomic displacement within each octahedron are quantitatively estimated.
Electroactive Biomaterials for Facilitating Bone Defect Repair under Pathological Conditions
Authors: Heng Boon Chin , Bai Yunyang , Li Xiaochan , Lim Lee Wei , Li Wang , Ge Zigang , Zhang Xuehui , Deng Xuliang 
Published: December 2022

AbstractBone degeneration associated with various diseases is increasing due to rapid aging, sedentary lifestyles, and unhealthy diets. Living bone tissue has bioelectric properties critical to bone remodeling, and bone degeneration under various pathological conditions results in significant changes to these bioelectric properties. There is growing interest in utilizing biomimetic electroactive biomaterials that recapitulate the natural electrophysiological microenvironment of healthy bone tissue to promote bone repair. This review first summarizes the etiology of degenerative bone conditions associated with various diseases such as type II diabetes, osteoporosis, periodontitis, osteoarthritis, rheumatoid arthritis, osteomyelitis, and metastatic osteolysis. Next, the diverse array of natural and synthetic electroactive biomaterials with therapeutic potential are discussed. Putative mechanistic pathways by which electroactive biomaterials can mitigate bone degeneration are critically examined, including the enhancement of osteogenesis and angiogenesis, suppression of inflammation and osteoclastogenesis, as well as their anti‐bacterial effects. Finally, the limited research on utilization of electroactive biomaterials in the treatment of bone degeneration associated with the aforementioned diseases are examined. Previous studies have mostly focused on using electroactive biomaterials to treat bone traumatic injuries. It is hoped that this review will encourage more research efforts on the use of electroactive biomaterials for treating degenerative bone conditions.
Development of a quantitative semi‐mechanistic model of Alzheimer's disease based on the amyloid/tau/neurodegeneration framework (the Q‐ATN model)
Authors: Mazer Norman A. , Hofmann Carsten , Lott Dominik , Gieschke Ronald , Klein Gregory , Boess Frank , Grimm Hans Peter , Kerchner Geoffrey A. , Baudler‐Klein Monika , Smith Janice , Doody Rachelle S. ,   for the Alzheimer's Disease Neuroimaging Initiative
Published: December 2022

AbstractIntroductionA quantitative model of Alzheimer's disease (AD) based on the amyloid/tau/neurodegeneration biomarker framework (Q‐ATN model) was developed to sequentially link amyloid positron emission tomography (PET), tau PET, medial temporal cortical thickness, and clinical outcome (Clinical Dementia Rating – Sum of Boxes; CDR‐SB).MethodsPublished data and biologically plausible mechanisms were used to construct, calibrate, and validate the model. Clinical trial simulations were performed for different anti‐amyloid antibodies, including a 5‐year simulation of subcutaneous gantenerumab treatment.ResultsThe simulated time‐course of biomarkers and CDR‐SB was consistent with natural history studies and described the effects of several anti‐amyloid antibodies observed in trials with positive and negative (or non‐significant) outcomes. The 5‐year simulation predicts that the beneficial effects of continued anti‐amyloid treatment should increase markedly over time.DiscussionThe Q‐ATN model offers a novel approach for linking amyloid PET to CDR‐SB, and provides theoretical support for the potential clinical benefit of anti‐amyloid therapy.Highlights
A semi‐mechanistic model was developed to link amyloid/tau/neurodegeneration biomarkers to clinical outcome (Q‐ATN model).
The Q‐ATN model describes the disease progression seen in natural history studies.
Model simulations agree well with mean data from the aducanumab EMERGE study.
A 5‐year simulation of gantenerumab predicts greater benefit with longer treatment.
Volume atrophy in medial temporal cortex and verbal memory scores in American Indians: Data from the Strong Heart Study
Authors: Suchy‐Dicey Astrid , Su Yi , Buchwald Dedra S , Manson Spero M. , Reiman Eric M 
Published: December 2022

AbstractIntroductionDistinguishing Alzheimer's disease (AD) patient subgroups may optimize positive clinical outcomes. Cortical atrophy is correlated with memory deficits, but these associations are understudied in American Indians.MethodsWe collected imaging and cognition data in the Strong Heart Study (SHS), a cohort of 11 tribes across three regions. We processed 1.5T MRI using FreeSurfer and iterative principal component analysis. Linear mixed models estimated volumetric associations with diabetes.ResultsOver mean 7 years follow‐up (N = 818 age 65–89 years), overall volume loss was 0.5% per year. Significant losses associated with diabetes were especially strong in the right hemisphere. Annualized hippocampal, parahippocampal, entorhinal atrophy were worse for men, older age, diabetes, hypertension, stroke; and associated with both encoding and retrieval memory losses.DiscussionOur findings suggest that diabetes is an important risk factor in American Indians for cortical atrophy and memory loss. Future research should examine opportunities for primary prevention in this underserved population.
Light‐Fueled Transformations of a Dynamic Cage‐Based Molecular System
Authors: Ovalle Marco , Kathan Michael , Toyoda Ryojun , Stindt Charlotte N. , Crespi Stefano , Feringa Ben L. 
Published: December 2022

AbstractIn a chemical equilibrium, the formation of high‐energy species—in a closed system—is inefficient due to microscopic reversibility. Here, we demonstrate how this restriction can be circumvented by coupling a dynamic equilibrium to a light‐induced E/Z isomerization of an azobenzene imine cage. The stable E‐cage resists intermolecular imine exchange reactions that would “open” it. Upon switching, the strained Z‐cage isomers undergo imine exchange spontaneously, thus opening the cage. Subsequent isomerization of the Z‐open compounds yields a high‐energy, kinetically trapped E‐open species, which cannot be efficiently obtained from the initial E‐cage, thus shifting an imine equilibrium energetically uphill in a closed system. Upon heating, the nucleophile is displaced back into solution and an opening/closing cycle is completed by regenerating the stable all‐E‐cage. Using this principle, a light‐induced cage‐to‐cage transformation is performed by the addition of a ditopic aldehyde.
Nine‐Electron Transfer of Binder Synergistic π‐d Conjugated Coordination Polymers as High‐Performance Lithium Storage Materials
Authors: Wu Yiwen , Shen Jiadong , Sun Zhaoyu , Yang Yan , Li Fangkun , Ji Shaomin , Zhu Min , Liu Jun 
Published: December 2022

AbstractTo solve the problems such as the dissolution and the poor conductivity of organic small molecule electrode materials, we construct π‐d conjugated coordination polymer Ni‐DHBQ with multiple redox‐active centers as lithium storage materials. It exhibits an ultra‐high capacity of 9‐electron transfers, while the π‐d conjugation and the laminar structure inside the crystal ensure fast electron transport and lithium ion diffusion, resulting in excellent rate performance (505.6 mAh g−1 at 1 A g−1 after 300 cycles). The interaction of Ni‐DHBQ with the binder CMC synergistically inhibits its dissolution and anchors the Ni atoms, thus exhibiting excellent cycling stability (650.7 mAh g−1 at 0.1 A g−1 after 100 cycles). This work provides insight into the mechanism of lithium storage in π‐d conjugated coordination polymers and the synergistic effect of CMC, which will contribute to the molecular design and commercial application of organic electrode materials.
A Conformational Restriction Strategy for the Control of CRISPR/Cas Gene Editing with Photoactivatable Guide RNAs**
Authors: Sun Ying‐Jie , Chen Wen‐Da , Liu Ji , Li Jun‐Jin , Zhang Yu , Cai Wei‐Qi , Liu Li , Tang Xin‐Jing , Hou Jian , Wang Ming , Cheng Liang 
Published: December 2022

AbstractThe CRISPR/Cas system is one of the most powerful tools for gene editing. However, approaches for precise control of genome editing and regulatory events are still desirable. Here, we report the spatiotemporal and efficient control of CRISPR/Cas9‐ and Cas12a‐mediated editing with conformationally restricted guide RNAs (gRNAs). This approach relied on only two or three pre‐installed photo‐labile substituents followed by an intramolecular cyclization, representing a robust synthetic method in comparison to the heavily modified linear gRNAs that often require extensive screening and time‐consuming optimization. This tactic could direct the precise cleavage of the genes encoding green fluorescent protein (GFP) and the vascular endothelial growth factor A (VEGFA) protein within a predefined cutting region without notable editing leakage in live cells. We also achieved light‐mediated myostatin (MSTN) gene editing in embryos, wherein a new bow‐knot‐type gRNA was constructed with excellent OFF/ON switch efficiency. Overall, our work provides a significant new strategy in CRISPR/Cas editing with modified circular gRNAs to precisely manipulate where and when genes are edited.
Electrostatic Shielding Boosts Electrochemical Performance of Alloy‐Type Anode Materials of Sodium‐Ion Batteries
Authors: Zheng Cheng , Ji Deluo , Yao Qian , Bai Zhongchao , Zhu Yansong , Nie Chuanhao , Liu Duo , Wang Nana , Yang Jian , Dou Shixue 
Published: December 2022

AbstractThe applications of alloy‐type anode materials for Na‐ion batteries are always obstructed by enormous volume variation upon cycles. Here, K+ ions are introduced as an electrolyte additive to improve the electrochemical performance via electrostatic shielding, using Sn microparticles (μ‐Sn) as a model. Theoretical calculations and experimental results indicate that K+ ions are not incorporated in the electrode, but accumulate on some sites. This accumulation slows down the local sodiation at the “hot spots”, promotes the uniform sodiation and enhances the electrode stability. Therefore, the electrode maintains a high specific capacity of 565 mAh g−1 after 3000 cycles at 2 A g−1, much better than the case without K+. The electrode also remains an areal capacity of ≈3.5 mAh cm−2 after 100 cycles. This method does not involve time‐consuming preparation, sophisticated instruments and expensive reagents, exhibiting the promising potential for other anode materials.
Dearomatization of Biaryls through Polarity Mismatched Radical Spirocyclization
Authors: Azpilcueta‐Nicolas Carlos R. , Meng Derek , Edelmann Simon , Lumb Jean‐Philip 
Published: December 2022

AbstractDearomatization reactions involving radical cyclizations can facilitate the synthesis of complex polycyclic systems that find applications in medicinal chemistry and natural product synthesis. Here we employ redox‐neutral photocatalysis to affect a radical spirocyclization that transforms biaryls into spirocyclic cyclohexadienones under mild reaction conditions. In a departure from previously reported methods, our work demonstrates the polarity mismatched addition of a nucleophilic radical to an electron rich arene, and allows the regioselective synthesis of 2,4‐ or 2,5‐cyclohexadienones with broad functional group tolerance. By transforming biaryls into spirocycles, our methodology accesses underexplored three‐dimensional chemical space, and provides an efficient means of creating quaternary spirocenters that we apply to the first synthesis of the cytotoxic plant metabolite denobilone A.
Isomeric Oligo(Phenylenevinylene)‐Based Covalent Organic Frameworks with Different Orientation of Imine Bonds and Distinct Photocatalytic Activities
Authors: Dong Wenbo , Qin Zhiying , Wang Kuixing , Xiao Yueyuan , Liu Xiangyang , Ren Shijie , Li Longyu 
Published: December 2022

AbstractImine‐linked covalent organic frameworks (COFs) have been extensively studied in photocatalysis because of their easy synthesis and excellent crystallinity. The effect of imine‐bond orientation on the photocatalytic properties of COFs, however, is still rarely studied. Herein, we report two novel COFs with different orientations of imine bonds using oligo(phenylenevinylene) moieties. The COFs showed similar structures but great differences in their photoelectric properties. COF‐932 demonstrated a superior hydrogen evolution performance compared to COF‐923 when triethanolamine was used as the sacrificial agent. Interestingly, the use of ascorbic acid led to the protonation of the COFs, further altering the direction of electron transfer. The photocatalytic performances were increased to 23.4 and 0.73 mmol g−1 h−1for protonated COF‐923 and COF‐932, respectively. This study provides a clear strategy for the design of imine‐linked COF‐based photocatalysts and advances the development of COFs.
An entropy‐centric equilibrium cooperative theory for the melting behavior of nonideal triaclylglycerol mixtures
Authors: Marangoni Alejandro G. , Ghazani Saeed M. , Pensini Erica 
Published: December 2022

AbstractA new nonideal, equilibrium thermodynamics model was developed for the prediction of the solid fat content (SFC) of edible fats, which are mixtures of triaclylglycerols (TAGs). The SFC is the most dominant material structural parameter which influences macroscopic mechanical properties and functionality in foods, cosmetics and pharmaceutical incipients. By taking into consideration the entropy of mixing and the activity coefficient of a TAG in an effective solid medium, we calculate a freezing point depression. The new melting point is then nested into an equilibrium expression for the melting of that TAG in such effective solid medium. The model assumes that complex mixtures of TAGs consist of one solid phase in a specific polymorphic form and one liquid phase, obeying mass balances and the overall TAG composition determined experimentally. The SFC is then just the summation of the amount of solid TAG components in the mixture. Novel insights are gained from estimates of a cooperativity index for the melting of the different TAGs in the effective solid medium, while estimated solid‐state activity coefficients speak to interactions of particular TAGs with the effective medium. The model was successfully fitted to eight different SFC‐temperature profiles of complex fats and parameter estimates obtained and interpreted.
A review of research and application of polylactic acid composites
Authors: Li Xiangrui , Lin Yu , Liu Mingli , Meng Lipeng , Li Chunfeng 
Published: December 2022

AbstractPolylactic acid (PLA) is a thermoplastic polyester that has received widespread attention for its environmentally friendly origin and excellent performance, and its potential to address the current problems of severe white pollution and scarcity of petroleum resources. This article focuses on the synthesis, modification, degradation and application of PLA. The main focus is on the modification of PLA with different environmentally friendly materials (natural organic materials, biodegradable polymers, inorganic minerals) in blends for defects such as the brittleness of PLA. In addition, the applications of PLA composites in the fields of construction, medical, packaging and oil and water separation are also introduced, which hopefully will provide some help to the promotion of PLA.