bluuebunny/crossref_metadata_2025 huggingface dataset:
Mixing states of light‐absorbing particles measured using a transmission electron microscope and a single‐particle soot photometer in Tokyo, Japan
Authors: Adachi Kouji , Moteki Nobuhiro , Kondo Yutaka , Igarashi Yasuhito
Published: July 2016

Light‐absorbing atmospheric aerosols such as carbonaceous particles influence the climate through absorbing sunlight. The mixing states of these aerosol particles affect their optical properties. This study examines the changes in the mixing states and abundance of strongly light absorbing carbonaceous particles by using transmission electron microscopy (TEM) and single‐particle soot photometer (SP2), as well as of iron oxide particles, in Tokyo, Japan. TEM and SP2 use fundamentally different detection techniques for the same light‐absorbing particles. TEM allows characterization of the morphological, chemical, and structural features of individual particles, whereas SP2 optically measures the number, size, and mixing states of black carbon (BC). A comparison of the results obtained using these two techniques indicates that the peaks of high soot (nanosphere soot (ns‐soot)) concentration periods agree with those of the BC concentrations determined by SP2 and that the high Fe‐bearing particle fraction periods measured by TEM agree with that of high number concentrations of iron oxide particles measured using SP2 during the first half of the observation campaign. The results also show that the changes in the ns‐soot/BC mixing states primarily correlate with the air mass sources, wind speed, precipitation, and photochemical processes. Nano‐sized, aggregated, iron oxide particles mixed with other particles were commonly observed by using TEM during the high iron oxide particle periods. We conclude that although further quantitative comparison between TEM and SP2 data will be needed, the morphologically and optically defined ns‐soot and BC, respectively, are essentially the same substance and that their mixing states are generally consistent across the techniques.
Recurring slope lineae and chlorides on the surface of Mars
Authors: Mitchell J. L. , Christensen P. R.
Published: July 2016

Recurring Slope Lineae (RSL) are dark streaks that appear on steep slopes on the Martian surface. While their apparent movement suggests liquid flow, remote sensing studies have not found evidence of fresh water. Some RSL have been observed at temperatures below the freezing point of water; if liquid water is present, therefore, it is likely in the form of a brine. In contrast to studies of other dissolved species such as perchlorates, this study explores the possibility of chloride as a dissolved component in RSL. Using Thermal Emission Imaging System decorrelation stretch products and High‐Resolution Imaging Science Experiment images, the presence of chloride lag deposits at RSL sites was assessed on a global scale. Though faint potential chloride signatures were detected at two RSL sites, emissivity spectra showed no significant variation from surrounding geology. No other RSL showed indications of chlorides. Using a simple model, the upper limit of chloride required for positive detection is estimated to be ~30 ± 15 g/m2. The total brine required to produce a detectable lag deposit is ~80 ± 35 mL/m2 at a eutectic concentration of calcium chloride. Over the last climate cycle, brine production could be up to 8 ± 3 × 10−4 mL/m2‐yr without producing a detectable lag deposit. Based on these results, we conclude that chloride abundance is not the limiting factor for RSL generation. RSL could be produced by capillary wicking of chloride‐rich brines to the surface, where small amounts of brine produce lag deposits below the detection limits of currently orbiting instruments.
Identification of cell‐nucleation mechanism in foam injection molding with gas‐counter pressure via mold visualization
Authors: Shaayegan Vahid , Mark Lun Howe , Park Chul B. , Wang Guilong
Published: July 2016

The mechanisms of cell nucleation and growth are investigated in foam injection molding (FIM) using gas‐counter pressure (GCP). An in‐situ mold visualization technique is employed. The application of GCP suppresses cell nucleation, and prevents the blowing agent from escaping during mold‐filling. The inherent structural heterogeneity in the regular FIM can be improved because of the uniform cavity pressure when employing GCP. The cavity pressure profiles show much faster pressure‐drop rates using GCP, because the single‐phase polymer/gas mixture has a lower compressibility than the two‐phase polymer/bubble mixture. Therefore, both the cell nucleation and growth rates are significantly increased through a higher pressure‐drop rate on the removal of the GCP. The effect of GCP magnitude on the cell morphology is explored. When the GCP is lower than the solubility pressure, bimodal foaming occurs. As the GCP increases above the solubility pressure, the cell density increases because of the higher pressure‐drop rate. © 2016 American Institute of Chemical Engineers AIChE J, 62: 4035–4046, 2016
A water droplet size distribution dependent modeling of hydrate formation in water/oil emulsion
Authors: Lv Yi‐Ning , Sun Chang‐Yu , Liu Bei , Chen Guang‐Jin , Gong Jing
Published: July 2016

Experimental data on chord length distributions and growth rate during methane hydrate formation in water‐in‐oil emulsions were obtained in a high pressure stirring reactor using focused beam reflectance measurement and particle video microscope. The experiments were carried out at 274.2 K for 10–30% water cuts and agitation rates ranging from 200 to 500 rpm initially at 7.72 MPa. Rapid growth was accompanied by gradually decrease in rate. Free water was observed to become depleted during rapid growth while some water remained encapsulated inside hydrate layers constituting a mass transfer barrier. The apparent kinetic constants of methane hydrate formation and free‐water fractions were determined using a newly developed kinetic model independent of the dissolution rate at the gas–oil interface. It was illustrated that continued growth depends on distribution and transfer of water in oil‐dominated systems. This perception accords with observations of hydrate film growth on suspended water droplet in oil and clarifies transfer limits in kinetics. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1010–1023, 2017
Particle dynamics and relaxation in bimodal suspensions during drying using multispeckle diffusing wave spectroscopy
Authors: Oh Gwi Jeong , Hwang Ji Won , Bong Ki Wan , Jung Hyun Wook , Lee Seong Jae
Published: July 2016

The motion of polystyrene particles in a bimodal suspension drop during drying was characterized via multispeckle diffusing wave spectroscopy. The fast and slow dynamics of bimodal particles, which were expressed in terms of autocorrelation function data from two kinds of cameras, were well connected in short and long lag time regimes. Characteristic time of β‐relaxation, representing the rapid movement of bimodal particles, became lower in the short lag time region as the portion of small particles increased, reflecting their fast Brownian motion. The difference in the relaxation features between bimodal suspension with large and small particles and unimodal suspension with only large particles became more evident as the size ratio between particles was high. Drying temperature could encourage the particle movement at the early stages of drying, leading to lower relaxation time, and inversely retard the relaxation behavior when drying time further elapsed, due to the structural rearrangement of particles. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1114–1121, 2017
Using generalizability analysis to estimate parameters for anatomy assessments: A multi‐institutional study
Authors: Byram Jessica N. , Seifert Mark F. , Brooks William S. , Fraser‐Cotlin Laura , Thorp Laura E. , Williams James M. , Wilson Adam B.
Published: July 2016

With integrated curricula and multidisciplinary assessments becoming more prevalent in medical education, there is a continued need for educational research to explore the advantages, consequences, and challenges of integration practices. This retrospective analysis investigated the number of items needed to reliably assess anatomical knowledge in the context of gross anatomy and histology. A generalizability analysis was conducted on gross anatomy and histology written and practical examination items that were administered in a discipline‐based format at Indiana University School of Medicine and in an integrated fashion at the University of Alabama School of Medicine and Rush University Medical College. Examination items were analyzed using a partially nested design
in which items were nested within occasions (i:o) and crossed with students (s). A reliability standard of 0.80 was used to determine the minimum number of items needed across examinations (occasions) to make reliable and informed decisions about students' competence in anatomical knowledge. Decision study plots are presented to demonstrate how the number of items per examination influences the reliability of each administered assessment. Using the example of a curriculum that assesses gross anatomy knowledge over five summative written and practical examinations, the results of the decision study estimated that 30 and 25 items would be needed on each written and practical examination to reach a reliability of 0.80, respectively. This study is particularly relevant to educators who may question whether the amount of anatomy content assessed in multidisciplinary evaluations is sufficient for making judgments about the anatomical aptitude of students. Anat Sci Educ 10: 109–119. © 2016 American Association of Anatomists.
Shedding light on the extra thermal stability of thermophilic proteins
Authors: Pica Andrea , Graziano Giuseppe
Published: July 2016

An entropic stabilization mechanism has recently gained attention and credibility as the physical ground for the extra thermal stability of globular proteins from thermophilic microorganisms. An empirical result, obtained from the analysis of thermodynamic data for a large set of proteins, strengthens the general reliability of the theoretical approach originally devised to rationalize the occurrence of cold denaturation [Graziano, PCCP 2014, 16, 21755–21767]. It is shown that this theoretical approach can readily account for the entropic stabilization mechanism. On decreasing the conformational entropy gain associated with denaturation, the thermal stability of a model globular protein increases markedly.
Metabolomic profiles delineate the effect of Sanmiao wan on hyperuricemia in rats
Authors: Jiang Tingwang , Qian Jianping , Ding Jiarong , Wang Guokun , Ding Xueyan , Liu Suxuan , Chen Wei
Published: July 2016

A serum metabolomic method based on ultra‐high‐performance liquid chromatography coupled with mass spectrometry was developed to characterize hyperuricemia‐related metabolic profiles and delineate the mechanism of Sanmiao wan (SMW), a traditional Chinese medicine (TCM), in treating hyperuricemic rats. With partial least‐squares discriminant analysis for classification and selection of biomarkers, 13 potential biomarkers in mouse serum were identified in the screen, primarily involved in purine metabolism, arginine and proline metabolism, citrate cycle, phenylalanine metabolism, tryptophan metabolism and glycerophospholipid metabolism. Taking these potential biomarkers as screening indexes, SMW could reverse the pathological process of hyperuricemia through partially regulating the perturbed metabolic pathway except for glycerophospholipid metabolism. Our results showed that a metabolomic approach offers a useful tool to identify hyperuricemia‐related biomarkers and provides a new methodological cue for systematically dissecting the underlying efficacies and mechanisms of TCM in treating hyperuricemia.
An LC–MS/MS method for rapid and sensitive high‐throughput simultaneous determination of various protein kinase inhibitors in human plasma
Authors: Abdelhameed Ali S. , Attwa Mohamed W. , Kadi Adnan A.
Published: July 2016

A reliable, high‐throughput and sensitive LC–MS/MS procedure was developed and validated for the determination of five tyrosine kinase inhibitors in human plasma. Following their extraction from human plasma, samples were eluted on a RP Luna®‐PFP 100 Å column using a mobile phase system composed of acetonitrile and 0.01 m ammonium formate in water (pH ~4.1) with a ratio of (50:50, v/v) flowing at 0.3 mL min−1. The mass spectrometer was operating with electrospray ionization in the positive ion multiple reaction monitoring mode. The proposed methodology resulted in linear calibration plots with correlation coefficients values of r2 = 0.9995–0.9999 from concentration ranges of 2.5–100 ng mL−1 for imatinib, 5.0–100 ng mL−1 for sorafenib, tofacitinib and afatinib, and 1.0–100 ng mL−1 for cabozantinib. The procedure was validated in terms of its specificity, limit of detection (0.32–1.71 ng mL−1), lower limit of quantification (0.97–5.07 ng mL−1), intra‐ and inter assay accuracy (−3.83 to +2.40%) and precision (<3.37%), matrix effect and recovery and stability. Our results demonstrated that the proposed method is highly reliable for routine quantification of the investigated tyrosine kinase inhibitors in human plasma and can be efficiently applied in the rapid and sensitive analysis of their clinical samples.
Metabolic profiles of the Flos Abelmoschus manihot extract by intestinal bacteria from the normal and CKD model rats based on UPLC‐Q‐TOF/MS
Authors: Du Le‐yue , Tao Jin‐hua , Jiang Shu , Qian Da‐wei , Guo Jian‐ming , Duan Jin‐ao
Published: July 2016

Flos Abelmoschus manihot is a traditional herbal medicine widely used in clinical practice to tackle chronic kidney disease (CKD) for thousands of years. Nowadays, many studies indicate that gut bacteria are closely related to the progression of CKD and CKD‐related complications. In this study, a UPLC‐Q‐TOF/MS method coupled with the MetaboLynx™ software was established and successfully applied to investigate the metabolites and metabolic profile of Flos A. manihot extract by intestinal bacteria from normal and CKD rats. Eight parent components and eight metabolites were characterized by their protonated ions. Among these compounds, 15 were detected in the two group samples while M16 was only determined in the CKD model samples. Compared with the quercetin‐type glycosides, fewer myricetin‐type and gossypetin‐type metabolites were obtained in the two group samples. These metabolites suggested that deglycosylation and methylation are the major metabolic pathways of Flos A. manihot extract. Few differences of metabolite classes were observed in the two group samples. However, the concentrations of aglycones such as quercetin, myricetin and gossypetin in the normal samples were notably higher than those in the CKD model samples. The results are important in unravelling the pharmacological effects of A. manihot and clarifying its mechanism of action in vivo.
A Comparative Study on Essential Oil Intraspecific and Seasonal Variations: Melissa romana Mill. and Melissa officinalis L. from Sardinia
Authors: Usai Marianna , Atzei Aldo Domenico , Marchetti Mauro
Published: July 2016

Two species of Melissa are currently present in Sardinia: Melissa officinalis L. and Melissa romana Mill. Our research can only count on a few supported evidences (as reported in Flora Italiana and Moris) and some notes on new stations in Sardinia that give us some information about morphology, distribution, bioecological, and ethnobotanical characteristics of both species. In this paper, we present the results of the research about morphological aspects of M. romana vs. M. officinalis, and their essential oils in different stations at different phenological periods. Moreover, we compared the essential oil of M. romana with the one obtained from M. officinalis growing in the few naturalized stations still present in Sardinia. The most evident morphological differences between the two entities are the long‐stalked capitate glandular trichomes, shorts and inclined capitate trichomes, and peltate hairs. The chemical composition of essential oil presents several significant differences between the species. In fact, oils show that in none of the phenological stages, M. romana recalls in its composition M. officinalis. Major distinctions are also evident between dry and fresh plants, and among essential oils distilled in different seasons.
Influence of Morphological Variability and Habitat on the Chemical Composition of Essential Oils of an Algerian Endemic Origanum Species (Origanum floribundum Munby)
Authors: Daoudi‐Merbah Farida , Hazzit Mohamed , Dahmani‐Megrerouche Malika
Published: July 2016

The genus Origanum L. (Lamiaceae) enjoys a socioeconomic interest and constitutes one of the most popular spices. In the literature, the study of this taxon is limited mainly to the chemical composition, antimicrobial, antifungal, and antioxidant activities of the essential oils. In Algeria, few works have been done in this area, including the endemic and rare species: Origanum floribundum Munby. In this study, our contribution highlights the influence of the ecological parameters and of the variation of morphological traits on the chemical composition and the antioxidant activity of the essential oils of six populations. The major oils constituents are carvacrol, γ‐terpinene, and p‐cymene with carvacrol predominance (31.8 – 60.8%) in over five populations (MS1 – MS4 and MS6). However, the population of Ain Terraeur (MS5) of which individuals present a foliar polymorphism, distinguishes itself by p‐cymene predominance (42.6%). This would denote a new chemotype and/or variety which seem well differentiated on the dendrogram of the Ascending Hierarchical Classification (A.H.C) and its foliar morphology. The antioxidant activity of the six samples evaluated by the scavenging activity of free radicals DPPH• and ABTS•+ showed a potent efficiency for the sample with foliar polymorphism population (IC50 = 51.6 ± 0.31 and 12.71 ± 0.37 μg/ml, respectively).
Phenolic Compounds and Antioxidant Activity of Different Organs of Potentilla fruticosa L. from Two Main Production Areas of China
Authors: Yu Danmeng , Pu Wenjun , Li Dengwu , Wang Dongmei , Liu Qiaoxiao , Wang Yongtao
Published: July 2016

This report compared the phenolic compounds and antioxidant activity of the leaves, flowers, and stems of Potentilla fruticosa L. collected from two main production areas of P. R. China (Taibai Mountains and the Qinghai Huzhu Northern Mountains). The results indicated that there were significant differences in the phenol contents and antioxidant activities among the different organs and between the two productions. High‐performance liquid‐chromatography analysis indicated that hyperoside, (+)‐catechin, ellagic acid, and rutin were the primary compounds in leaves and flowers; for stems, the content of six phenolic compounds, from two productions, were the lowest. The 1,1‐diphenyl‐2‐picryl hydrazyl (DPPH), 2,2‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) di‐ammonium salt (ABTS), ferric reducing power (FRAP), lipid peroxidation assays, and microbial test system (MTS) were used to evaluate the antioxidant activity. The results demonstrated that the leaves from two productions exhibited powerful antioxidant activity than other organs, which did not significantly differ from that of the positive control (rutin), followed by the flowers and stems. The correlation between the content of phytochemicals and the antioxidant activities of different organs showed that the total phenol, tannin, hyperoside, and (+)‐catechin contents may influence the antioxidant activity, and these compounds can be used as markers for the quality control of P. fruticosa.
Rational Molecular Design of Potent PLK1 PBD Domain‐binding Phosphopeptides Using Preferential Amino Acid Building Blocks
Authors: Mao Xin‐Li , Wang Kui‐Feng , Zhu Feng , Pan Zhao‐Hu , Wu Guo‐Min , Zhu Hong‐Yuan
Published: July 2016

Polo‐like kinase 1 (PLK1) is an important regulator in diverse aspects of the cell cycle and proliferation. The protein has a highly conserved polo‐box domain (PBD) present in C‐terminal noncatalytic region, which exhibits a relatively broad sequence specificity in recognizing and binding phosphorylated substrates to control substrate phosphorylation by the kinase. In order to elucidate the structural basis, thermodynamic property, and biological implication underlying PBD‐substrate recognition and association, a systematic amino acid preference profile of phosphopeptide interaction with PLK1 PBD domain was established via virtual mutagenesis analysis and mutation energy calculation, from which the contribution of different amino acids at each residue position of two reference phosphopeptides to domain–peptide binding was characterized comprehensively and quantitatively. With the profile, we are able to determine the favorable, neutral, and unfavorable amino acid types for each position of PBD‐binding phosphopeptides, and we also explored the molecular origin of the broad sequence specificity in PBD‐substrate recognition. To practice computational findings, the profile was further employed to guide rational design of potent PBD binders; three 6‐mer phosphopeptides (i.e., IQSpSPC, LQSpTPF, and LNSpTPT) were successfully developed, which can efficiently target PBD domain with high affinity (Kd = 5.7 ± 1.1, 0.75 ± 0.18, and 7.2 ± 2.6 μm, resp.) as measured by a fluorescence anisotropy assay. The complex structure of PLK1 PBD domain with a newly designed, potent phosphopeptide LQSpTPF as well as diverse noncovalent chemical forces, such as H‐bonds and hydrophobic interactions at the complex interface, were examined in detail to reveal the molecular mechanism of high affinity and stability of the complex system.
Bioactive Coumarins from the Stems of Clausena emarginata
Authors: Ouyang Guo‐Qing , Li Chuang‐Jun , Yang Jing‐Zhi , Li Li , Song Xiu‐Yun , Jiang Yi‐Na , Chen Nai‐Hong , Ma Jie , Zhang Dong‐Ming
Published: July 2016

Five new coumarins, clauemarmarins I – M (1 – 4), together with 10 known analogs (5 – 14), were isolated from the stems of Clausena emarginata. Compounds 8 – 13 were obtained from this plant for the first time. Their structures were established and elucidated by comprehensive analysis of spectroscopic data. The absolute configurations of 1 – 4 were further determined by their electronic circular dichroism spectroscopy. Compounds 5, 7, 12, and 14 exhibited inhibitory effects on LPS‐induced NO production. Compounds 5 – 7 showed selective neuroprotective effects in Aβ25 – 35 model at 10 μm.
Antimicrobial Activity of Scabiosa arenaria Forssk. Extracts and Pure Compounds Using Bioguided Fractionation
Authors: Besbes Hlila Malek , Mosbah Habib , Majouli Kaouther , Ben Nejma Aymen , Ben Jannet Hichem , Mastouri Maha , Aouni Mahjoub , Selmi Boulbaba
Published: July 2016

The emergence of multidrug resistant pathogens threatened the clinical efficacy of many existing antibiotics. This situation has been recognized globally as a serious concern and justifies further research to discover antimicrobial agents from natural origins including plant extracts. The aim of our work was to evaluate the antimicrobial activities of Scabiosa arenaria Forssk. extracts and pure compounds using a bioguided fractionation, and try to explain some traditional use of this genus. The best antimicrobial activity‐guided fractionation was obtained by BuOH fractions of flowers, fruits and (stems and leaves) against Escherichia coli, Pseudomonas aeruginosa and Candida albicans with minimum inhibitory concentration (MIC) values from 0.0195 to 5 mg/ml. Escherichia coli was the most affected bug, thus the MIC of fruits BuOH extract showed the best anti‐Escherichia coli activity (MIC = 0.0195 mg/ml), followed by the (stems and leaves) and flowers BuOH extracts; MIC = 0.078 and 0.15 mg/ml, respectively. Furthermore, the subfractions obtained from these three mixed fractions showed also an important antimicrobial activity against the three microorganisms, with MIC values between 0.0195 and 0.312 mg/ml. The fractionation of the aerial part BuOH fraction led to the isolation of oleanolic acid (1) and luteolin 7‐O‐glucopyranoside (2) which are reported here for the first time from S. arenaria. Both compounds showed good antimicrobial activities with MIC values ranging from 170 to 683 μm and 86 to 347 μm, respectively. These results support the use of the Scabiosa genus to inhibit the growth of tested pathogenic bacteria and yeasts which may reduce illnesses associated with their exposure.
Essential Oil Composition of Centaurea atropurpurea and Centaurea orientalis Inflorescences from the Central Balkans – Ecological Significance and Taxonomic Implications
Authors: Novaković Jelica , Rajčević Nemanja , Milanovici Sretco , Marin Petar D. , Janaćković Pedja
Published: July 2016

The essential oil composition of Centaurea atropurpurea and Centaurea orientalis flowering heads (capitula) from Central Balkans have been determined by GC‐FID and GC/MS analyses. In total, 121 compounds were identified, representing on average 97.7% of the oil composition. In all samples, sesquiterpenes were most abundant group, representing 53.9 – 74.0% of the total oil. Sesquiterpene hydrocarbons dominated in all studied populations of C. orientalis and C. atropurpurea, except C. atropurpurea f. flava in which essential oil was characterized with high level of oxygenated sesquiterpenes. The dominant components differed between species, and also between typical C. atropurpurea and C. atropurpurea f. flava. The most abundant compounds of essential oil of C. orientalis were germacrene D and α‐cadinol. In C. atropuruprea, germacrene D and β‐caryophyllene were the most abundant, while caryophyllene oxide and β‐caryophyllene were dominant in C. atropurpurea f. flava oil. Taxonomical and ecological implications are further discussed.
Chemical Constituents from the Stems of Daphne holosericea (Diels) Hamaya
Authors: Ma Qing‐Yun , Chen Yi‐Chun , Huang Sheng‐Zhuo , Kong Fan‐Dong , Zhou Li‐Man , Dai Hao‐Fu , Hua Yan , Zhao You‐Xing
Published: July 2016

Two new compounds, one flavanol dimer dapholosericol A (1) and one tigliane diterpene dapholosericin A (2), together with ten known ones, were isolated from the AcOEt extract of Daphne holosericea (Diels) Hamaya. Their structures were elucidated by their spectroscopic data analysis. Compounds 1 and 2 showed moderate activities against acetylcholinesterase with inhibition ratio of 36% and 29% at a concentration of 100 μmol/l, respectively.
Improved Biological Activities of Isoepoxypteryxin by Biotransformation
Authors: Mira Amira , Alkhiary Wael , Zhu Qinchang , Nakagawa Toshinori , Tran Hai‐Bang , Amen Yhiya M. , Shimizu Kuniyoshi
Published: July 2016

Isoepoxypteryxin is the major coumarin of a Japanese medicinal plant Angelica shikokiana. This research was designed to study the effect of structural changes through fungal biotransformation on the reported biological activities of isoepoxypteryxin. Among the tested microorganisms, only Cordyceps sinensis had enzymes that could catalyze the ester hydrolysis and the reductive cleavage of the epoxide ring of isoepoxypteryxin, separately, to give two more polar metabolites (+)‐cis‐khellactone (P1) and a new coumarin derivative (+)‐cis‐3′‐[(2‐methyl‐3‐hydroxybutanoyl)oxy]‐4′‐acetoxy‐3′,4′‐dihydroseselin (P2), respectively. The polar metabolite P2 showed stronger cytotoxicity and higher selectivity than isoepoxypteryxin. On the molecular level, P2 showed more in vitro inhibition of both tubulin polymerization and histone deacetylase 8 (HDAC8). Similarly, P2 showed more neuroprotection against amyloid beta fragment 1 – 42 (Aβ1 – 42)‐induced neurotoxicity in human neuroblastoma cells (SH‐SY5Y) and exhibited more inhibition of the in vitro aggregation of Aβ1 – 42. Both metabolites showed stronger antiplatelet aggregation by increased inhibition of thromboxane‐A2 synthase (TXS) activity and thromboxane‐A2 (TXA2) production. This study is the first to describe the improved cytotoxic, neuroprotective, and antiplatelet aggregation activities of isoepoxypteryxin through its biotransformation by C. sinensis.
Phytochemical, Ecological and Antioxidant Evaluation of Wild Sicilian Thyme:Thymbra capitata(L.)Cav.
Authors: Saija Antonella , Speciale Antonio , Trombetta Domenico , Leto Claudio , Tuttolomondo Teresa , La Bella Salvatore , Licata Mario , Virga Giuseppe , Bonsangue Giuseppe , Gennaro Maria Cristina , Napoli Edoardo , Siracusa Laura , Ruberto Giuseppe
Published: July 2016

In a broad survey conducted throughout the Sicily region, 45 different sites were identified where thyme grows wild. All the biotypes collected were classified asThymbra capitata(L.) Cav. (syn.Thymus capitatus(L.)Hoffmanns. &Link). Cluster analysis based on the main morphological characteristics of the plant led to the division of the biotypes into 3 major groups. All samples were analyzed for their secondary phytochemical metabolites identified in the extracts and the essential oils.LC‐UV‐DAD/ESI‐MSandGC‐FID/GC‐MShave been applied to characterize the extracts and the essential oils, respectively. In the extracts, 15 flavonoid derivatives with taxifolin‐di‐O‐glucoside and thymusin as main components, and 2 organic acids, with a large predominance of rosmarinic acid, were identified. On the whole 37 compounds were fully characterized in the essential oils, carvacrol was identified as the main component with an average value of 73.93%. The total phenol content and the antioxidant activity of all phytochemical complexes were determined with theFolin–Ciocalteu(FC) assay, theUVradiation‐induced peroxidation in liposomal membranes (UV‐IPtest), and the scavenging activity of superoxide radical ().
Barks Essential Oil, Secondary Metabolites and Biological Activities of Four Organs of Tunisian Calligonum azel Maire
Authors: Bannour Marwa , Aouadhi Chedia , Khalfaoui Houssem , Aschi‐Smiti Samira , Khadhri Ayda
Published: July 2016

This study is the first to investigate the chemical composition of barks essential oil (EO), secondary metabolites and biological activities of the MeOH and infusions extracts of seeds, leaves, barks and roots of Calligonum azel Maire (Polygonaceae) harvested from Tunisian desert. The gas chromatography/mass spectrometry (GC/MS) results showed the presence of fifty‐four compounds in barks EO. The major components were: viridiflorol (14.6%), α‐eudesmol (8.65%), trans‐caryophyllene (6.72%), elemol (6.63%), β‐eudesmol (6.21%). The obtained results showed that C. azel is a very rich plant in secondary metabolites. High contents in polyphenols, flavonoids and tannins were observed in both extracts of all studied organs. Significant differences were found between both extracts of the four organs. Thus, polyphenols and tannins were more abundant in leaves infusion extract, while, flavonoids showed a high level in barks extract. The antioxidant activity data demonstrated that all extracts showed strong antioxidant and radical scavenging activities. The MeOH extracts presented potential for antibacterial and antifungal activities against all tested microorganisms. The inhibition zones diameters and minimal inhibitrice concentration values were in the range of 9 – 15 mm and 2.5 – 20 μg/ml, respectively. This study demonstrated that C. azel can be regarded as an excellent plant source for natural antimicrobial agents.
Chemical Composition, Antioxidant, and Antimicrobial Activities on Laserpitium carduchorumHedge & Lamond Essential Oil and Extracts During Various Growing Stages
Authors: Dastan Dara , Salehi Peyman , Maroofi Hossein
Published: July 2016

Laserpitium carduchorum is frequently used as a spice, and in Bane folk medicine, the aerial parts of this are used to treat urinary infections. Variation in the quantity and quality of the essential oil of Iranian L. carduchorum at different developmental growth stages including vegetative, flowering, and seed ripening is reported. In total, 33 compounds were identified and quantified in the oils of vegetative, flowering, and seed ripening stages, representing 97.8%, 98.8%, and 98.7% of the oils, respectively. α‐Pinene (45.1, 61.4, and 46.4%), sabinene (16.5, 10.3, and 17.5%), and limonene (6.4, 8.5, and 20.4%) were the main compounds in all samples. The antioxidant activities of different extracts of L. carduchorum at different developmental growth stages were examined by employing various established in vitro experiments including DPPH, FRAP, and TEAC assays. The amounts of total phenolics were also determined spectrophotometerically. Antimicrobial activities of different extracts and essential oils of L. carduchorum at different developmental growth stages were examined against five Gram‐positive and four Gram‐negative bacteria, as well as two fungi. The results showed that maximum antioxidant and antimicrobial activity of extracts were at the flowering stage of the plant. Maximum antimicrobial activity of essential oils was at seed ripening stage.
The Phenolics of the Ornithogalum umbellatum L. (Hyacinthaceae): Phytochemical and Ecological Characterization
Authors: Rat Milica M. , Gavaric Neda S. , Kladar Nebojsa V. , Andric Andrijana M. , Anackov Goran T. , Bozin Biljana N.
Published: July 2016

Ornithogalum umbellatum L. is a widely distributed species in Europe, that exhibits considerable variability at ecological, morphological, anatomical, and karyological level. Previous reports of the chemical investigations among Ornithogalum species indicate significant diversity of the secondary metabolites, as well. Knowing that environment affects the phenolic composition in plants to a large extent, the main objective of the research was to define relationship between phytochemical and ecological characters. To estimate an environmental influence on these results, plant material was collected at four habitats that differ in ecological factors and belong to two biogeographical regions: the Balkan Peninsula and the Pannonian Plane. Measured phytochemical characters are yield of dry extract, total phenolic and flavonoid contents, the presence of selected phenolic compounds as well as free‐radical scavenging activity (neutralization of DPPH and OH radicals). Results revealed that all analyzed phytochemical parameters differ between investigated O. umbellatum samples. The moisture level of habitat has the highest correlation, either positive or negative, with most of phytochemical characters, and is followed by temperature and soil reaction. Light intensity and nitrogen level have mostly moderate correlation coefficient with phytochemical characters. More complex correlation is revealed between ecological factors and nine phenolic compounds, with three observed patterns of relationship.
Cytotoxic Oleanane‐Type Saponins from the Leaves of Albizia anthelminticaBrongn.
Authors: Al‐Sayed Eman , Eldahshan Omayma A. , Bahgat Dina M. , Singab Abdel Nasser B.
Published: July 2016

Two new oleanane‐type saponins: β‐d‐xylopyranosyl‐(1 → 4)‐6‐deoxy‐α‐l‐mannopyranosyl‐(1 → 2)‐1‐O‐{(3β)‐28‐oxo‐3‐[(2‐O‐β‐d‐xylopyranosyl‐β‐d‐glucopyranosyl)oxy]olean‐12‐en‐28‐yl}‐β‐d‐glucopyranose (1) and 1‐O‐[(3β)‐28‐oxo‐3‐{[β‐d‐xylopyranosyl‐(1 → 2)‐α‐l‐arabinopyranosyl‐(1 → 6)‐2‐acetamido‐2‐deoxy‐β‐d‐glucopyranosyl]oxy}olean‐12‐en‐28‐yl]β‐d‐glucopyranose (2), along with two known saponins: (3β)‐3‐[(β‐d‐Glucopyranosyl‐(1 → 2)‐β‐d‐glucopyranosyl)oxy]olean‐12‐en‐28‐oic acid (3) and (3β)‐3‐{[α‐l‐arabinopyranosyl‐(1 → 6)‐[β‐d‐glucopyranosyl‐(1 → 2)]‐β‐d‐glucopyranosyl]oxy}olean‐12‐en‐28‐oic acid (4) were isolated from the acetone‐insoluble fraction obtained from the 80% aqueous MeOH extract of Albizia anthelmintica Brongn. leaves. Their structures were identified using different NMR experiments including: 1H‐ and 13C‐NMR, HSQC, HMBC and 1H,1H‐COSY, together with HR‐ESI‐MS/MS, as well as by acid hydrolysis. The four isolated saponins and the fractions of the extract exhibited cytotoxic activity against HepG‐2 and HCT‐116 cell lines. Compound 2 showed the most potent cytotoxic activity among the other tested compounds against the HepG2 cell line with an IC50 value of 3.60μm. Whereas, compound 1 showed the most potent cytotoxic effect with an IC50 value of 4.75μm on HCT‐116 cells.
Quantification of Anti‐Addictive Alkaloids Ibogaine and Voacangine in In Vivo‐ and In Vitro‐Grown Plants of Two Mexican Tabernaemontana Species
Authors: Krengel Felix , Herrera Santoyo Josefina , Olivera Flores Teresa de Jesús , Chávez Ávila Víctor M. , Pérez Flores Francisco J. , Reyes Chilpa Ricardo
Published: July 2016

Tabernaemontana alba and Tabernaemontana arborea are Apocynaceae species used in Mexican traditional medicine for which little phytochemical information exists. In this study, preliminary gas chromatography/mass spectrometry analyses of different organs obtained from wild plants of both species identified a total of 10 monoterpenoid indole alkaloids (MIAs) and one simple indole alkaloid, nine of which were reported for the first time in these species. Furthermore, callus cultures were established from T. alba leaf explants and regeneration of whole plants was accomplished via somatic embryogenesis. The anti‐addictive MIAs ibogaine and voacangine were then quantified by gas chromatography with flame ionization detection in wild plants of both species, as well as greenhouse‐grown plants, in vitro‐grown plantlets and embryogenic callus of T. alba. Ibogaine and voacangine were present in most samples taken from the whole plants of both species, with stem and root barks showing the highest concentrations. No alkaloids were detected in callus samples. It was concluded that T. alba and T. arborea are potentially viable sources of ibogaine and voacangine, and that these MIAs can be produced through somatic embryogenesis and whole plant regeneration of T. alba. Approaches to increase MIA yields in whole plants and to achieve alkaloid production directly in cell cultures are discussed.
Aroma Profile of Rubus ulmifolius Flowers and Fruits During Different Ontogenetic Phases
Authors: Bandeira Reidel Rose Vanessa , Melai Bernardo , Cioni Pierluigi , Flamini Guido , Pistelli Luisa
Published: July 2016

The chemical composition of spontaneous volatile emission from Rubus ulmifolius flowers and fruits during different stages of development was evaluated by HS‐SPME‐GC/MS. In total, 155 chemical compounds were identified accounting 84.6 – 99.4% of whole aroma profile of flowers samples and 92.4 – 96.6% for fruit samples. The main constituents were α‐copaene, β‐caryophyllene, germacrene D, (E,E)‐α‐farnesene, 1,7‐octadien‐3‐one,2‐methyl‐6‐methylene, tridecane, (E)‐2‐hexenol acetate, (E)‐3‐hexenol acetate and cyperene. The results give a chemotaxonomic contribution to the characterization of the VOCs emitted from flowers and fruits during their ontogenic development.
Luteolin and apigenin activate the Oct‐4/Sox2 signal via NFATc1 in human periodontal ligament cells
Authors: Liu Lu , Peng Zhengjun , Huang Haoquan , Xu Zhezhen , Wei Xi
Published: July 2016

Identifying small molecules to activate the Oct‐4/Sox2‐derived pluripotency network represents a hopeful and safe method to pluripotency without genetic manipulation. Luteolin and apigenin, two major bioactive flavonoids, enhance reprogramming efficiency and increase expression of Oct‐4/Sox2/c‐Myc, albeit the detailed mechanism regulating pluripotency in dental‐derived cells remains unknown. In the present study, to elucidate the effect of luteolin/apigenin on pluripotency of periodontal ligament cells (PDLCs) through interaction with downstream signals, we examined cell cycle, proliferation, apoptosis, expression of Oct‐4/Sox2/c‐Myc, and multilineage differentiation of PDLCs with luteolin/apigenin treatment. Moreover, we profiled the differentially expressed pluripotency genes by PCR arrays. Our results demonstrated that luteolin/apigenin restrained cell proliferation, increased apoptosis, and arrested PDLCs in G2/M and S phase. Luteolin and apigenin activated expression of Oct‐4, Sox2, and c‐Myc in a time‐ and dose‐dependent pattern, and repressed lineage‐specific differentiation. PCR arrays profiled multiple signals in PDLCs with luteolin/apigenin treatment, among which NFATc1 was the major upregulated gene. Notably, blocking of the NFATc1 signal with INCA‐6 significantly decreased mRNA and protein expression of Oct‐4, Sox2, and c‐Myc in PDLCs with luteolin/apigenin treatment, indicating that NFATc1 may act as an upstream modulator of Oct‐4/Sox2 signal. Taken together, this study showed that luteolin and apigenin effectively maintain pluripotency of PDLCs through activation of Oct‐4/Sox2 signal via NFATc1.
The Effects of Different Aspirin Dosing Frequencies and the Timing of Aspirin Intake in Primary and Secondary Prevention of Cardiovascular Disease: A Systematic Review
Authors: Bem D , Lordkipanidzé M , Hodgkinson J , Stevens S , Bayliss S , Moore D , Fitzmaurice D , Dretzke J
Published: July 2016

Enhancing the effectiveness of aspirin by tailoring administration regimens is an important question among health professionals. We conducted a systematic review to evaluate the evidence on the effects of different aspirin regimens in terms of timing (chronotherapy) or frequency of dosing in the prevention of cardiovascular disease. Only two out of the 28 included studies reported long‐term cardiovascular outcomes, highlighting an evidence gap that future research should address. The remaining 26 studies used surrogate outcomes.
Photocatalytic Carbon Dioxide Reduction at p‐Type Copper(I) Iodide
Authors: Baran Tomasz , Wojtyła Szymon , Dibenedetto Angela , Aresta Michele , Macyk Wojciech
Published: July 2016

A p‐type semiconductor, CuI, has been synthesized, characterized, and tested as a photocatalyst for CO2 reduction under UV/Vis irradiation in presence of isopropanol as a hole scavenger. Formation of CO, CH4, and/or HCOOH was observed. The photocatalytic activity of CuI was attributed to the very low potential of the conduction band edge (i.e., −2.28 V vs. NHE). Photocurrents generated by the studied material confirm a high efficiency of the photoinduced interfacial electrontransfer processes. Our studies show that p‐type semiconductors may be effective photocatalysts for CO2 reduction, even better than extensively studied n‐type titanium dioxide, owing to the low potential of the conduction band edge.
Reversible CO2 Capture by Conjugated Ionic Liquids through Dynamic Covalent Carbon–Oxygen Bonds
Authors: Pan Mingguang , Cao Ningning , Lin Wenjun , Luo Xiaoyan , Chen Kaihong , Che Siying , Li Haoran , Wang Congmin
Published: July 2016

The strong chemisorption of CO2 is always accompanied by a high absorption enthalpy, and traditional methods to reduce the absorption enthalpy lead to decreased CO2 capacities. Through the introduction of a large π‐conjugated structure into the anion, a dual‐tuning approach for the improvement of CO2 capture by anion‐functionalized ionic liquids (ILs) resulted in a high capacity of up to 0.96 mol
 
and excellent reversibility. The increased capacity and improved desorption were supported by quantum chemical calculations, spectroscopic investigations, and thermogravimetric analysis. The increased capacity may be a result of the strengthened dynamic covalent bonds in these π‐electron‐conjugated structures through anion aggregation upon the uptake of CO2, and the improved desorption originates from the charge dispersion of interaction sites through the large π‐electron delocalization. These results provide important insights into effective strategies for CO2 capture.
Nociceptive Alteration by High Sucrose Diet in Hypoestrogenic Wistar Rats
Authors: Jaramillo‐Morales Osmar Antonio , Espinosa‐Juárez Josué Vidal , Corona‐Ramos Janette Nallely , López‐Muñoz Francisco Javier
Published: July 2016

Preclinical Research

Obesity is a risk factor associated with alterations in pain perception. The aim of this study was to analyse a time‐course of nociceptive responses (plantar test) in hypoestrogenic rats after the induction of obesity. Animals (hypoestrogenic and naïve) received either a hypercaloric or regular diet for 24 weeks. Thermal nociception and body weight were measured during this period. At the 4th and 17th weeks after treatment, oral glucose tolerance, blood insulin levels, abdominal fat weight, and uric acid levels were measured. The hypoestrogenic rats on a high sucrose diet had higher body weight and abdominal fat weight than control rats. A biphasic response was observed in the ovariectomized group fed with sucrose with thermal latency being decreased in the fourth week. During weeks 12–18, thermal latency increased compared to that of the hypoestrogenic control. There were no differences in basal blood glucose levels at the 4th and 17th weeks; however, oral glucose tolerance, insulin, and uric acid levels were altered. This indicated that increased body weight and fat as well as alteration sin glucose tolerance, hyperinsulinemia and hyperuricemia, may be associated with the biphasic nociceptive response. Drug Dev Res 77 : 258–266, 2016. © 2016 Wiley Periodicals, Inc.
25C‐NBOMe and 25I‐NBOMe metabolite studies in human hepatocytes, in vivo mouse and human urine with high‐resolution mass spectrometry
Authors: Wohlfarth Ariane , Roman Markus , Andersson Mikael , Kugelberg Fredrik C. , Diao Xingxing , Carlier Jeremy , Eriksson Caroline , Wu Xiongyu , Konradsson Peter , Josefsson Martin , Huestis Marilyn A. , Kronstrand Robert
Published: July 2016

25C‐NBOMe and 25I‐NBOMe are potent hallucinogenic drugs that recently emerged as new psychoactive substances. To date, a few metabolism studies were conducted for 25I‐NBOMe, whereas 25C‐NBOMe metabolism data are scarce. Therefore, we investigated the metabolic profile of these compounds in human hepatocytes, an in vivo mouse model and authentic human urine samples from forensic cases.

Cryopreserved human hepatocytes were incubated for 3 h with 10 μM 25C‐NBOMe and 25I‐NBOMe; samples were analyzed by liquid chromatography high‐resolution mass spectrometry (LC‐HRMS) on an Accucore C18 column with a Thermo QExactive; data analysis was performed with Compound Discoverer software (Thermo Scientific). Mice were administered 1.0 mg drug/kg body weight intraperitoneally, urine was collected for 24 h and analyzed (with or without hydrolysis) by LC‐HRMS on an Acquity HSS T3 column with an Agilent 6550 QTOF; data were analyzed manually and with WebMetabase software (Molecular Discovery). Human urine samples were analyzed similarly.

In vitro and in vivo results matched well. 25C‐NBOMe and 25I‐NBOMe were predominantly metabolized by O‐demethylation, followed by O‐di‐demethylation and hydroxylation. All methoxy groups could be demethylated; hydroxylation preferably occurred at the NBOMe ring. Phase I metabolites were extensively conjugated in human urine with glucuronic acid and sulfate. Based on these data and a comparison with synthesized reference standards for potential metabolites, specific and abundant 25C‐NBOMe urine targets are 5’‐desmethyl 25C‐NBOMe, 25C‐NBOMe and 5‐hydroxy 25C‐NBOMe, and for 25I‐NBOMe 2’ and 5’‐desmethyl 25I‐NBOMe and hydroxy 25I‐NBOMe. These data will help clinical and forensic laboratories to develop analytical methods and to interpret results. Copyright © 2016 John Wiley & Sons, Ltd.