bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phytochemical Analysis, Biological Activity, and Secretory Structures of Stachys annua (L.) L. subsp. annua (Lamiaceae) from Central Italy
Authors: Venditti Alessandro , Bianco Armandodoriano , Quassinti Luana , Bramucci Massimo , Lupidi Giulio , Damiano Silvia , Papa Fabrizio , Vittori Sauro , Maleci Bini Laura , Giuliani Claudia , Lucarini Domenico , Maggi Filippo 
Published: August 2015

AbstractStachys annua subsp. annua, well‐known in central Italy as ‘stregona annuale’, is an annual, small, slightly‐scented herb, commonly found in fields and uncultivated areas in almost all regions of Italy. In folk medicine, its aerial parts were used as anti‐catarrhal, febrifuge, tonic, and vulnerary. In the present work, the chemical composition of the flowering aerial parts was studied. The hydrodistilled volatile oil, analysed by GC/MS, showed sesquiterpenoids as the major fraction (42.5%); phytol (9.8%), germacrene D (9.2%), and spathulenol (8.5%) were the most abundant constituents. The volatile oil was assayed for antioxidant and cytotoxic activity by DPPH, ABTS, FRAP, and MTT methods. The cytotoxicity results against HCT116, A375, and MDA‐MB 231 human tumor cell lines were significant, with IC50 values of 23.5, 37.2, and 41.5 μg/ml, respectively, whereas the antioxidant power was negligible. The EtOH extract was composed mainly of three glycosidic flavonoids, namely 7‐{[2‐O‐(6‐O‐acetyl‐β‐D‐allopyranosyl)‐β‐D‐glucopyranosyl]oxy}‐5,8‐dihydroxy‐2‐(4‐methoxyphenyl)‐4H‐1‐benzopyran‐4‐one (1), 7‐{[6‐O‐acetyl‐2‐O‐(6‐O‐acetyl‐β‐D‐allopyranosyl)‐β‐D‐glucopyranosyl]oxy}‐2‐(3,4‐dihydroxyphenyl)‐5,8‐dihydroxy‐4H‐1‐benzopyran‐4‐one (2), and 7‐{[6‐O‐acetyl‐2‐O‐(β‐D‐allopyranosyl)‐β‐D‐glucopyranosyl]oxy}‐2‐(3‐hydroxy‐4‐methoxyphenyl)‐5,8‐dihydroxy‐4H‐1‐benzopyran‐4‐one (3). On the contrary, iridoids, considered chemotaxonomic markers of the genus Stachys, were absent in this species. Finally, the morphological and histochemical survey showed that glandular trichomes were composed of two main types, i.e. peltate type A and capitate types B and C giving positive response for both lipids and polyphenols.
Three New Isomeric Indole Alkaloids from Nauclea officinalis
Authors: Wang Hai‐Yang , Wang Ru‐Xia , Zhao Yan‐Xia , Liu Ke , Wang Feng‐Ling , Sun Jing‐Yong 
Published: August 2015

AbstractThree new isomeric monoterpene indole alkaloids, naucleofficines I–III (1–3, resp.) were isolated from the stems (with bark) of Nauclea officinalis. Their structures were elucidated on the basis of spectroscopic methods and single‐crystal diffraction analyses. The cytotoxic activities of 1–3 against human colon cancer, human gastric cancer, and human hepatoma cells were also investigated.
Biphenyl‐Type Neolignan Derivatives from the Twigs of Magnolia denudata and Their Anti‐Inflammatory Activity
Authors: Chung Ching‐Yi , Kuo Wen‐Lung , Hwang Tsong‐Long , Chung Mei‐Ing , Chen Jih‐Jung 
Published: August 2015

AbstractTwo new biphenyl‐type neolignan derivatives, 2‐[2‐(hydroxymethyl)‐1‐benzofuran‐5‐yl]‐4‐(prop‐2‐en‐1‐yl)phenol (1) and 2′‐ethoxy‐5,5′‐di(prop‐2‐en‐1‐yl)biphenyl‐2‐ol (2), were isolated from the twigs of Magnolia denudata, together with six known compounds (3–8). The structures of 1 and 2 were determined through extensive 1D‐ and 2D‐NMR and mass‐spectrometric analyses. Magnolol (6) and honokiol (7) exhibited potent inhibition (IC50 values=4.4±0.2 and 0.71±0.13 μg/ml, resp.) of O$\rm{{_{2}^{{^\cdot} -}}}$ generation by human nutrophils in response to N‐formyl‐L‐methionyl‐L‐leucyl‐L‐phenylalanine/cytochalasin B (fMLP/CB). In addition, 2‐[2‐(hydroxymethyl)‐1‐benzofuran‐5‐yl]‐4‐(prop‐2‐en‐1‐yl)phenol (1), 2′‐ethoxy‐5,5′‐di(prop‐2‐en‐1‐yl)biphenyl‐2‐ol (2), magnolol (6), and vanillic acid (8) inhibited fMLP/CB‐induced elastase release with IC50 values=6.4±1.5, 2.4±0.4, 1.5±0.2, and 4.8±0.5 μg/ml, respectively.
Polyanilines with Pendant Amino Groups as Electrochemically Active Copolymers at Neutral pH
Authors: Marmisollé Waldemar A. , Gregurec Danijela , Moya Sergio , Azzaroni Omar 
Published: August 2015

AbstractOne of the most promising fields of application of polyaniline (PANI)‐based modified electrodes is the construction of biosensors. However, PANI itself is not electroactive in neutral media. This problem can be solved by copolymerization of aniline with other monomers. Herein, we present a study of the electrosynthesis and electrochemical performance of copolymer films of 3‐aminobenzylamine and aniline. These films are both stable and electroactive in acid and neutral media. They can even be employed as mediators of ascorbic acid oxidation, showing variable electrocatalytic activity depending on the copolymer composition. The presence of different proportions of pendant amino groups was confirmed by using XPS. These groups are responsible for the increased electroactivity in neutral solution. The copolymer films studied here can be used as versatile building blocks in the construction of bioelectroactive assemblies.
In Situ Synthesis of Porous Carbons by Using Room‐Temperature, Atmospheric‐Pressure Dielectric Barrier Discharge Plasma as High‐Performance Adsorbents for Solid‐Phase Microextraction
Authors: Lin Yao , Wu Li , Xu Kailai , Tian Yunfei , Hou Xiandeng , Zheng Chengbin 
Published: August 2015

AbstractA one‐step, template‐free method is described to synthesize porous carbons (PCs) in situ on a metal surface by using a room‐temperature, atmospheric‐pressure dielectric barrier discharge (DBD) plasma. This method not only features high efficiency, environmentally friendliness, and low cost and simple equipment, but also can conveniently realize large‐area synthesis of PCs by only changing the design of the DBD reactor. The synthesized PCs have a regulated nestlike morphology, and thus, provide a high specific surface area and high pore volume, which result in excellent adsorption properties. Its applicability was demonstrated by using a PC‐coated stainless‐steel fiber as a solid‐phase microextraction (SPME) fiber to preconcentrate polycyclic aromatic hydrocarbons (PAHs) prior to analysis by gas chromatography with flame ionization detection (GC‐FID). The results showed that the fiber exhibited excellent enrichment factors (4.1×104 to 3.1×105) toward all tested PAHs. Thus, the PC‐based SPME‐GC‐FID provides low limits of detection (2 to 20 ng L−1), good precision (<7.8 %), and good recoveries (80–115 %) for ultra‐sensitive determination of PAHs in real water samples. In addition, the PC‐coated fiber could be stable enough for more than 500 replicate extraction cycles.
Iodine(III)‐Mediated Diazidation and Azido‐oxyamination of Enamides
Authors: Nocquet‐Thibault Sophie , Rayar Anita , Retailleau Pascal , Cariou Kevin , Dodd Robert H. 
Published: August 2015

AbstractIn this study we demonstrate that the combination of bis(tert‐butylcarbonyloxy)iodobenzene and lithium azide in acetonitrile allows the diazidation of various enamide substrates. The azido‐oxyamination of the same substrates can be carried out in the presence of 2,2,6,6‐tetramethylpiperidine N‐oxide (TEMPO). Control experiments strongly suggest that this latter process occurs through a shift in nature of the in situ generated electrophilic species from a radical to a cation. Finally, the versatility of the novel compounds synthesized was also assessed by running various selective reactions on them.
A Theoretical Insight into the Mechanism of Cu(I)‐Catalyzed CN Coupling between Aryl Halides and Aqueous Ammonia
Authors: Chen Ting , Yan Mingkuan , Zheng Chao , Yuan Jie , Xu Shen , Chen Runfeng , Huang Wei 
Published: August 2015

AbstractComputational investigations of Cu(I)‐catalyzed CN coupling between aryl halides and aqueous ammonia without addition of any base or ligand were reported. Density functional theory calculations were performed to reveal the mechanism of the ligand‐free amination reaction for the preparation of primary aromatic amines. Through systematic evaluation of the relative concentrations of possible Cu species in solution, we propose that the active catalyst is the neutral Cu(I) complexes rather than the Cu(I) cations; oxidative addition of aryl bromide is a facile step of the catalytic cycle; reactant (NH3) and solvent molecule (NMP) can act as ligands of Cu species to help reduce the activation energy of the forward reaction and increase the activation energy of the reverse reaction; except for Pathway B, the deprotonation step is irreversible due to the extreme exothermic feature; the elimination of H2O is kinetically favored, while that of HBr is thermodynamically preferred. These findings should be valuable for the mechanism understandings of the ligand‐free Cu‐catalyzed CN cross‐coupling reactions and for the further development of highly efficient amination catalyst systems.
Gold Nanoparticles for Cancer Theranostics
Authors: Liang Hong , Tian Huayu , Deng Mingxiao , Chen Xuesi 
Published: August 2015

AbstractGold nanoparticles have seen unprecedented development in the biomedical field, particularly for cancer therapy. They have received extensive attention because of their easy preparation, functionalization, biocompatibility, non‐cytotoxicity, and detectability. Functionalized gold nanoparticles can be applied in the fields of drug and gene delivery, photothermal therapy, and bioimaging. This review introduces methods for preparing various shapes of gold nanoparticles and describes their current applications in the field of cancer treatment. Moreover, the review presents the development routes and current issues of gold nanoparticles in clinical theranostics.
Discovery of Novel, Potent, and Specific Cell‐Death Inducers in the Jurkat Acute Lymphoblastic Leukemia Cell Line
Authors: Carosati Emanuele , van den Höfel Natascha , Reif Manuela , Randazzo Giuseppe Marco , Stanitzki Bettina , Stevens Julia , Gabbert Helmut E. , Cruciani Gabriele , Mannhold Raimund , Mahotka Csaba 
Published: August 2015

AbstractThe limited clinical efficacy of many cancer therapeutics has initiated intense research efforts toward the discovery of novel chemical entities in this field. In this study, 31 hit candidates were selected from nearly 800 000 database compounds in a ligand‐based virtual screening campaign. In turn, three of these hits were found to have (sub)micromolar potencies in proliferation assays with the Jurkat acute lymphatic leukemic cell line. In this assay, the three hits were found to exhibit higher potency than clinically tested cell‐death inducers (GDC‐0152, AT‐406, and birinapant). Importantly, antiproliferative activity toward non‐cancer peripheral blood mononuclear cells (PBMCs) was found to be marginal. Further biological characterization demonstrated the cell‐death‐inducing properties of these compounds. Biological testing of hit congeners excluded a nonspecific, toxic effect of the novel structures. Altogether, these findings may have profound relevance for the development of clinical candidates in tumor therapy.
MPI‐CMS: a hybrid parallel approach to geometrical motif search in proteins
Authors: Ferretti Marco , Musci Mirto , Santangelo Luigi 
Published: August 2015

SummaryThis paper describes the message passing parallel implementation of the Cross Motif Search algorithm (MPI‐CMS). It is an extension and specifically improves on the results obtained in a conference paper presented at PBIO 2014. CMS is a bioinformatics algorithm whose goal is to search for geometrical motifs in proteins. For the purpose of a complete characterization of protein similarities, it would be important to run CMS on the largest possible dataset. Unfortunately, due to its precision, CMS is inherently slow; thus, it was originally implemented using a shared memory parallel paradigm. In the original conference paper, we proved that the OpenMP implementation of Cross Motif Search (MP‐CMS) is extremely inefficient and cannot scale adequately. To solve the problem, we designed a new parallel implementation of CMS (MPI‐CMS) based on a hybrid shared memory and message passing paradigm. This paper reconsiders MPI‐CMS with the target to port it on a supercomputing machine. The focus is on the dependence of performance in the hybrid approach on the workload unbalance. Using a simple statistical analysis of the workload we discuss several strategies through which we can improve the design of MPI‐CMS. We conclude the paper describing a revised implementation of MPI‐CMS, which takes into account the size of the protein pairs to fine‐tune the parallelization strategy. Copyright © 2015 John Wiley & Sons, Ltd.
A DFT Study of Tungsten–Methylidene Formation on a W/ZSM‐5 Zeolite: The Metathesis Active Site
Authors: Maihom Thana , Probst Michael , Limtrakul Jumras 
Published: August 2015

AbstractTungsten–methylidene formation from ethene on either the WIV, WV, or WVI active sites of a W/ZSM‐5 zeolite is investigated by using the M06‐L functional. The reaction is assumed to proceed in two steps; the first step is the [2+2] cycloaddition between ethene and the W−O active site to form an oxametallacycle intermediate. The intermediate is then decomposed to produce the W–methylidene active site from the metathesis reaction. The overall activation barrier of the reaction on WVI (27.3 kcal mol−1) is considerably lower than the ones for WIV and WV (69.4 and 37.1 kcal mol−1, respectively). Moreover, the reaction involving the WVI site also stabilizes intermediates and products to a larger extent than the ones on the WIV and WV sites. As a result, we have demonstrated that the reaction of the W–methylidene metathesis active site is both kinetically and thermodynamically favored to occur on the WVI active site of the zeolite.
Depolymerization of Free‐Radical Polymers with Spin Migrations
Authors: Yu Tianrong , Gao Yang , Wang Bo , Dai Xing , Jiang Wanrun , Song Ruixia , Zhang Zhanwen , Jin Mingxing , Tang Yongjian , Wang Zhigang 
Published: August 2015

AbstractThe mechanism of depolymerization is one of the most essential issues in chemical engineering and materials science. In this work, we investigate the depolymerization reactions of three typical free‐radical poly(alpha‐methylstyrene) tetramers by using first‐principles density functional theory. The calculated results show that these reactions all need to overcome the energy barriers in the range of 0.58 to 0.77 eV, and that breaking the C−C bond at the chain end leads to the dissociation of alpha‐methylstyrene monomers from the polymers. Electronic‐structure analysis indicates that the reactions occur easily at the CR3 unsaturated end, and that the frontier molecular orbitals that participate in the reactions are mainly localized at the unsaturated ends. Meanwhile, spin population analysis presents the unique net spin‐transfer process in free‐radical depolymerization reactions. We hope the current findings can contribute to understanding the free‐radical depolymerization mechanism and help guide future experiments.
Linking Flavonoids to Gold – A New Family of Gold Compounds for Potential Therapeutic Applications
Authors: Mirzadeh Nedaossadat , Privér Steven H. , Abraham Amanda , Shukla Ravi , Bansal Vipul , Bhargava Suresh K. 
Published: August 2015

AbstractThe flavone ligands 8‐chloro‐2‐tetrahydrofuryl‐1,4‐benzopyrone and 8‐chloro‐2‐(2‐methyltetrahydrofuryl)‐1,4‐benzopyrone have been used to prepare the first examples of alkynyl phosphine gold compounds containing flavonoids which exhibit cytotoxicity towards human prostate cancer cells.
Selective [2+2] Cycloaddition Reactions of Isocyanates and Thioisocyanates across the M=C Bond in a Ruthenium Carbene Complex
Authors: Weismann Julia , Gessner Viktoria H. 
Published: August 2015

AbstractThe reactivity of the (carbene)ruthenium complex [(η6‐p‐cymene)Ru=CRR′] with the unsymmetrical methandiide ligand [CRR′=C(Ph2PS)(SO2Ph)] towards different unsaturated organic substrates was examined. While no transformation was observed with a series of different ketones (no Wittig‐type reactivity), treatment with isocyanates as well as thioisocyanates resulted in selective [2+2] cycloaddition reactions across the Ru=C double bond. The products were isolated in high yields and characterized in solution as well as in the solid state. The addition reactions were found to proceed selectively according to the HSAB principle with the soft ruthenium center preferring the softer donor atoms. Hence, isocyanate addition occurred with the C=N bond, while the thioisocyanates added to the metal–carbon bond with the C=S bond. Density functional theory studies on the reaction mechanism confirmed the observed selectivity and the formed complexes as kinetically as well as thermodynamically favoured products.
Textile dyes induce toxicity on zebrafish early life stages
Authors: de Oliveira Gisele Augusto Rodrigues , de Lapuente Joaquín , Teixidó Elisabet , Porredón Constança , Borràs Miquel , de Oliveira Danielle Palma 
Published: August 2015

Abstract

Textile manufacturing is one of the most polluting industrial sectors because of the release of potentially toxic compounds, such as synthetic dyes, into the environment. Depending on the class of the dyes, their loss in wastewaters can range from 2% to 50% of the original dye concentration. Consequently, uncontrolled use of such dyes can negatively affect human health and the ecological balance. The present study assessed the toxicity of the textile dyes Direct Black 38 (DB38), Reactive Blue 15 (RB15), Reactive Orange 16 (RO16), and Vat Green 3 (VG3) using zebrafish (Danio rerio) embryos for 144 h postfertilization (hpf). At the tested conditions, none of the dyes caused significant mortality. The highest RO16 dose significantly delayed or inhibited the ability of zebrafish embryos to hatch from the chorion after 96 hpf. From 120 hpf to 144 hpf, all the dyes impaired the gas bladder inflation of zebrafish larvae, DB38 also induced curved tail, and VG3 led to yolk sac edema in zebrafish larvae. Based on these data, DB38, RB15, RO16, and VG3 can induce malformations during embryonic and larval development of zebrafish. Therefore, it is essential to remove these compounds from wastewater or reduce their concentrations to safe levels before discharging textile industry effluents into the aquatic environment. Environ Toxicol Chem 2016;35:429–434. © 2015 SETAC
Structural insights into aberrant cortical morphometry and network organization in psychogenic erectile dysfunction
Authors: Zhao Lu , Guan Min , Zhang Xiangsheng , Karama Sherif , Khundrakpam Budhachandra , Wang Meiyun , Dong Minghao , Qin Wei , Tian Jie , Evans Alan C. , Shi Dapeng 
Published: August 2015

AbstractFunctional neuroimaging studies have revealed abnormal brain dynamics of male sexual arousal (SA) in psychogenic erectile dysfunction (pED). However, the neuroanatomical correlates of pED are still unclear. In this work, we obtained cortical thickness (CTh) measurements from structural magnetic resonance images of 40 pED patients and 39 healthy control subjects. Abnormalities in CTh related to pED were explored using a scale space search based brain morphometric analysis. Organizations of brain structural covariance networks were analyzed as well. Compared with healthy men, pED patients showed significantly decreased CTh in widespread cortical regions, most of which were previously reported to show abnormal dynamics of male SA in pED, such as the medial prefrontal, orbitofrontal, cingulate, inferotemporal, and insular cortices. CTh reductions in these areas were found to be significantly correlated with male sexual functioning degradation. Moreover, pED patients showed decreased interregional CTh correlations from the right lateral orbitofrontal cortex to the right supramarginal gyrus and the left angular cortex, implying disassociations between the cognitive, motivational, and inhibitory networks of male SA in pED. This work provides structural insights on the complex phenomenon of psychogenic sexual dysfunction in men, and suggests a specific vulnerability factor, possibly as an extra “organic” factor, that may play an important role in pED. Hum Brain Mapp 36:4469–4482, 2015. © 2015 Wiley Periodicals, Inc.
Bcl‐2 is required for the survival of doublecortin‐expressing immature neurons
Authors: Ceizar Maheen , Dhaliwal Jagroop , Xi Yanwei , Smallwood Megan , Kumar Keren Leviel , Lagace Diane C. 
Published: August 2015

ABSTRACTIn the adult brain only a small proportion of the neural stem and progenitor cells (NPCs) and their progeny survive to become mature neurons in the hippocampus. Recent studies have elucidated the roles for members of the B‐cell lymphoma‐2 (Bcl‐2) family of proteins in regulating the survival of NPCs and their progeny at different stages of maturation, yet the requirement of Bcl‐2 during this process remains unknown. Here we report that inducible removal of Bcl‐2 from nestin‐expressing neural stem/progenitor cells and their progeny resulted in a reduction in the survival of doublecortin‐expressing cells in the absence of changing the number of radial‐glial stem cells or dividing NPCs. The requirement of Bcl‐2 for the survival of maturing NPCs was confirmed by removal of Bcl‐2 through infecting NPCs using a retroviral strategy that resulted in the complete loss of Bcl‐2 null cells by 30‐day post‐viral injection. Furthermore, we observed that the function of Bcl‐2 in the adult‐generated neurons was dependent on the Bcl‐2‐associated X (BAX) protein, since Bcl‐2 null NPCs were rescued in BAX knockout mice. These results indicate that Bcl‐2 is an essential regulator in the survival of doublecortin‐expressing immature neurons through a mechanism that is upstream of BAX. © 2015 Wiley Periodicals, Inc.
Synthesis and NMR Spectroscopic Elucidation of Four Diastereoisomers of Oxygenated Bisabolane Side Chain
Authors: Hirai Misaki , Miyazaki Rurina , Mitsui Kana , Kiuchi Kota , Onuki Hiroyuki , Hirota Hiroshi , Kuroda Chiaki 
Published: August 2015

AbstractFour possible stereoisomers of a model compound of highly O‐bearing bisabolane sesquiterpenes were synthesized and their NMR spectra were compared. Starting from isopulegol, allylic oxidation and Grignard reaction afforded a mixture of alcohols at C(8), which was separated. After metathesis reaction, both α‐ and β‐epoxides were obtained via non‐stereoselective epoxidation, while VO(OiPr)3‐catalyzed epoxidation afforded a single diastereoisomer selectively. NMR Spectra of twelve synthesized compounds, four stereoisomers of acetates, isobutyrates, and tiglates, were measured. A difference between C(8α)‐ and C(8β)‐acyloxy isomers was observed in the δ‐values of HC(8) in CDCl3. Within the 8β‐acyloxy compounds, the α‐ and the β‐epoxides were distinguished by either the J‐value of HC(8) or the chemical shift of CH2(9). Within the 8α‐acyloxy compounds, two epoxide isomers were distinguished by the J‐value of HC(10) in C6D6 or in CD3OD.
Three New Lignan Derivatives from Lindera glauca (Siebold et Zucc.) Blume
Authors: Suh Won Se , Kim Ki Hyun , Kim Ho Kyung , Choi Sang Un , Lee Kang Ro 
Published: August 2015

AbstractTwo new aryl‐tetralin lignan glycosides, linderanosides A and B (1 and 2, resp.), and a new dihydrobenzofuran neolignan glycoside, linderanoside C (3), together with five known lignan derivatives (4–8) were isolated from the trunk of Lindera glauca. The structures of these new compounds were determined through spectroscopic analyses, including extensive 2D‐NMR data and acid hydrolysis. The absolute configurations of the compounds were clarified by circular dichroism (CD) spectroscopic studies. Compounds 1–8 were evaluated for their cytotoxicity against A549 (non‐small cell lung adenocarcinoma), SK‐OV‐3 (ovarian cancer cells), A498 (human kidney epithelial cells), and HCT‐15 (colon cancer cells) human tumor cell lines using sulforhodamine B assays in vitro.
Glycopentosides D – F, Three New Phenolic Glycosides from Glycosmis pentaphylla
Authors: Chen Yu , Tian Er‐Li , Hu Xin , Li Jun , Yang Guang‐Zhong 
Published: August 2015

AbstractA phytochemical investigation of the BuOH‐soluble fraction of the EtOH extract from the stems of Glycosmis pentaphylla resulted in the isolation of three new phenolic glycosides, glycopentosides D–F (1–3, resp.). Their structures were determined by using spectroscopic analysis including UV, 1H‐ and 13C‐NMR, DEPT, COSY, ROESY, HMBC, HSQC, HR‐ESI‐MS, and acid hydrolysis.