bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Anticonvulsant Properties of New 3,3‐Diphenyl‐2,5‐dioxo‐pyrrolidin‐1‐yl‐acetamides and 3,3‐Diphenyl‐propionamides
Authors: Obniska Jolanta , Rapacz Anna , Rybka Sabina , Góra Małgorzata , Żmudzki Paweł , Kamiński Krzysztof
Published: March 2017

The focused library of new amides derived from 3,3‐diphenyl‐2,5‐dioxo‐pyrrolidin‐1‐yl‐acetic acid (2a–t) and 3,3‐diphenyl‐propionic acid (3a–t) as potential anticonvulsant agents was synthesized. The final products were obtained in the amidation reaction of the given carboxylic acid (2, 3) with appropriate secondary amines in the presence of carbonyldiimidazole (CDI) as a coupling reagent. The initial anticonvulsant screening was performed in mice intraperitoneally (i.p.) using the “classical” maximal electroshock (MES) and subcutaneous pentylenetetrazole (scPTZ) seizure models, whereas the acute neurological toxicity was determined applying the rotarod test. Additionally, several compounds were studied also in the 6‐Hz seizures recognized as the animal model of human pharmacoresistant epilepsy. In this series, compound 3q displayed a broad spectrum of activity across the preclinical seizure models (ED50 MES = 31.64 mg/kg; ED50 scPTZ = 75.41 mg/kg, ED50 6‐Hz (32 mA) = 38.15 mg/kg). Consequently, compound 3q revealed a wider spectrum of protection, higher activity or/and a better safety profile than the commonly used antiepileptic drugs such as phenytoin, ethosuximide, valproic acid, or/and levetiracetam. Notably, the in vitro studies showed that the most possible mechanism of action of 3q may be connected to the interaction with neuronal voltage‐sensitive sodium channels (site 2). Other substances were active predominantly in the chemically induced seizures. The results of the current studies indicate that the presence of the pyrrolidine‐2,5‐dione ring is important but not indispensable for anticonvulsant activity.
Design, Synthesis, and Evaluation of the Kinase Inhibition Potential of Pyridylpyrimidinylaminophenyl Derivatives
Authors: Manchanda Priyanka , Parshad Badri , Kumar Amit , Tiwari Rakesh K. , Shirazi Amir N. , Parang Keykavous , Sharma Sunil K.
Published: March 2017

In view of potent kinase inhibitors for the treatment of myriad human disorders, we synthesized some structurally variant amide/cyclic amide derivatives based on pyridylpyrimidinylaminophenyl amine, the key pharmacophore of the kinase inhibitor drug molecule, imatinib, and evaluated their kinase inhibition potency. Among the various synthesized amides, compound 20, a cyclic amide/pyridin‐2(1H)‐one derivative, exhibited an IC50 value comparable to that of the drug imatinib against c‐Src kinase, and another compound (14) containing a 2‐((4‐methyl‐2‐oxo‐2H‐chromen‐6‐yl)oxy)acetamide demonstrated an IC50 value of 8.39 μM. Furthermore, the constitution of the cyclic amide derivative was confirmed by the single‐crystal X‐ray diffraction technique. These results may serve as a gateway for developing novel next‐generation kinase inhibitors.
Synthesis of Mixed Objective Output Feedback Robust Model Predictive Control
Authors: Jiang Wei , Wang Hongli , Lu Jinghui , Qin Weiwei , Cai Guangbin
Published: March 2017

Aiming at the constrained polytopic uncertain system with energy‐bounded disturbance and unmeasurable states, a novel synthesis scheme to design the output feedback robust model predictive control(MPC)is put forward by using mixed H2/H∞ design approach. The proposed scheme involves an offline design of a robust state observer using linear matrix inequalities(LMIs)and an online output feedback robust MPC algorithm using the estimated states in which the desired mixed objective robust output feedback controllers are cast into efficiently tractable LMI‐based convex optimization problems. In addition, the closed‐loop stability and the recursive feasibility of the proposed robust MPC are guaranteed through an appropriate reformulation of the estimation error bound (EEB). A numerical example subject to input constraints illustrates the effectiveness of the proposed controller.
Urbane Sicherheit bei Explosionen – Schutz durch Bepflanzung
Authors: Gebbeken Norbert
Published: March 2017

Die Absicherung urbaner Räume vor terroristischen Gefahren erfordert neue Lösungen des baulichen Schutzes, die nicht als solche wahrgenommen werden. Dazu gehören Elemente der Stadtmöblierung und der Landschaftsarchitektur. Dieser Artikel beschreibt numerische und experimentelle Untersuchungen zur Schutzwirkung von Pflanzen bei Explosionsdruckwellen. Es zeigt sich, dass Pflanzen mit bestimmten Eigenschaften den Explosionsdruck um bis zu 60 % abmindern. Diese ersten Untersuchungen werfen jedoch auch einige Fragen auf, die es mithilfe weiterer Forschungsarbeiten zu beantworten gilt.
A Bayesian subgroup analysis using collections of ANOVA models
Authors: Liu Jinzhong , Sivaganesan Siva , Laud Purushottam W. , Müller Peter
Published: March 2017

We develop a Bayesian approach to subgroup analysis using ANOVA models with multiple covariates, extending an earlier work. We assume a two‐arm clinical trial with normally distributed response variable. We also assume that the covariates for subgroup finding are categorical and are a priori specified, and parsimonious easy‐to‐interpret subgroups are preferable. We represent the subgroups of interest by a collection of models and use a model selection approach to finding subgroups with heterogeneous effects. We develop suitable priors for the model space and use an objective Bayesian approach that yields multiplicity adjusted posterior probabilities for the models. We use a structured algorithm based on the posterior probabilities of the models to determine which subgroup effects to report. Frequentist operating characteristics of the approach are evaluated using simulation. While our approach is applicable in more general cases, we mainly focus on the 2 × 2 case of two covariates each at two levels for ease of presentation. The approach is illustrated using a real data example.
Hydroxytyrosol restores proper insulin signaling in an astrocytic model of Alzheimer's disease
Authors: Crespo M. Carmen , Tomé‐Carneiro Joao , Pintado Cristina , Dávalos Alberto , Visioli Francesco , Burgos‐Ramos Emma
Published: March 2017

Recent epidemiological evidence demonstrated that diabetes is a risk factor for AD onset and development. Indeed, meta‐analyses of longitudinal epidemiologic studies show that diabetes increases AD risk by 50–100%, being insulin resistance (IR) the main binding link between diabetes and AD. Astrocytes are the foremost cerebral macroglial cells and are responsible for converting glucose into lactate and transfer it to neurons that use it as fuel, but Aβ(1‐42) impairs insulin signaling and glycogen storage. Recent prospective studies showed that the Mediterranean diet is associated with lower incidence of AD. We hypothesized that hydroxytyrosol (HT, the preeminent polyphenol of olives and olive oil) could exert beneficial effects on IR associated with AD and investigated it mechanisms of action in an astrocytic model of AD. The astrocytic cell line C6 was exposed to Aβ(25‐35) and co‐incubated with HT for different periods. After treatment with Aβ(25‐35), astrocytes' viability was significantly decreased as compared with controls; however, both pre‐ and post‐treatment with HT prevented this effect. Mechanistically, we found that the preventive role of HT on Aβ(25‐35)‐ induced cytotoxicity in astrocytes is moderated by an increased HT‐induced activation of Akt, which is mediated by the insulin signaling pathway. In addition, we report that HT prevented the pronounced activation of mTOR, thereby restoring proper insulin signaling. In conclusion, we demonstrate that HT protects Aβ(25‐35)‐treated astrocytes by improving insulin sensitivity and restoring proper insulin‐signaling. These data provide some mechanistic insight on the observed inverse association between olive oil consumption and prevalence of cognitive impairment. © 2017 BioFactors, 43(4):540–548, 2017
Clinical implications of serum N‐glycan profiling as a diagnostic and prognostic biomarker in germ‐cell tumors
Authors: Narita Takuma , Hatakeyama Shingo , Yoneyama Tohru , Narita Shintaro , Yamashita Shinichi , Mitsuzuka Koji , Sakurai Toshihiko , Kawamura Sadafumi , Tochigi Tatsuo , Takahashi Ippei , Nakaji Shigeyuki , Tobisawa Yuki , Yamamoto Hayato , Koie Takuya , Tsuchiya Norihiko , Habuchi Tomonori , Arai Yoichi , Ohyama Chikara
Published: March 2017

Serum biomarker monitoring is essential for management of germ‐cell tumors (GCT). However, not all GCT are positive for conventional tumor markers. We examined whether serum N‐glycan‐based biomarkers can be applied for detection and prognosis in patients with GCT. We performed a comprehensive N‐glycan structural analysis of sera from 54 untreated GCT patients and 103 age‐adjusted healthy volunteers using glycoblotting methods and mass spectrometry. Candidate N‐glycans were selected from those with the highest association; cutoff concentration values were established, and an N‐glycan score was created based on the number of positive N‐glycans present. The validity of this score for diagnosis and prognosis was analyzed using a receiver operating characteristic (ROC) curve. We identified five candidate N‐glycans significantly associated with GCT patients. The accuracy of the N‐glycan score for GCT was significant with an area‐under‐the‐curve (AUC) value of 0.87. Diagnostically, the N‐glycan score detected 10 of 12 (83%) patients with negative conventional tumor markers. Prognostically, the N‐glycan score comprised four candidate N‐glycans. The predictive value of the prognostic N‐glycan score was significant, with an AUC value of 0.89. A high value prognostic N‐glycan score was significantly associated with poor prognosis. Finally, to identify a potential carrier protein, immunoglobulin (Ig) fractions of sera were subjected to N‐glycan analysis and compared to whole sera. Candidate N‐glycans in Ig‐fractions were significantly decreased; therefore, the carrier protein for candidate N‐glycans is likely not an immunoglobulin. In summary, our newly developed N‐glycan score seems to be a practical diagnostic and prognostic method for GCT.
Tobacco use and outcome in radical prostatectomy patients
Authors: Curtis Alexandra , Ondracek Rochelle Payne , Murekeyisoni Christine , Kauffman Eric , Mohler James , Marshall James
Published: March 2017

Cigarette smoking has been consistently associated with increased risk of overall mortality, but the importance of smoking for patients with prostate cancer (CaP) who are candidates for curative radical prostatectomy (RP) has received less attention. This retrospectively designed cohort study investigated the association of smoking history at RP with subsequent CaP treatment outcomes and overall mortality. A total of 1981 patients who underwent RP at Roswell Park Cancer Institute (RPCI) between 1993 and 2014 were studied. Smoking history was considered as a risk factor for overall mortality as well as for currently accepted CaP treatment outcomes (biochemical failure, treatment failure, distant metastasis, and disease‐specific mortality). The associations of smoking status with these outcomes were tested by Cox proportional hazard analyses. A total of 153 (8%) patients died during follow‐up. Current smoking at diagnosis was a statistically significant predictor of overall mortality after RP (current smokers vs. former and never smokers, hazards ratio 2.07, 95% confidence interval [CI]: 1.36–3.14). This association persisted for overall mortality at 3, 5, and 10 years (odds ratios 2.07 [95% CI: 1.36–3.15], 2.05 [95% CI: 1.35–3.12], and 1.8 [95% CI: 1.18–2.74], respectively). Smoking was not associated with biochemical failure, treatment failure, distant metastasis, or CaP‐specific mortality, and the association of smoking with overall mortality did not appear to be functionally related to treatment or biochemical failure, or to distant metastasis. Smoking is a non‐negligible risk factor for death among CaP patients who undergo RP; patients who smoke are far more likely to die of causes other than CaP.
Trend analysis and survival of primary gallbladder cancer in the United States: a 1973–2009 population‐based study
Authors: Rahman Rubayat , Simoes Eduardo J. , Schmaltz Chester , Jackson Christian S. , Ibdah Jamal A.
Published: March 2017

Primary gallbladder cancer is an aggressive and uncommon cancer with poor outcomes. Our study examines epidemiology, trend, and survival of gallbladder cancer in the United States from 1973 to 2009. We utilized the Surveillance Epidemiology and End Results database (SEER). Frequency and rate analyses on demographics, stage, and survival were compared among non‐Hispanic whites, Hispanics, African American, and Asian/Pacific Islanders. A total of 18,124 cases were reported in SEER from 1973 to 2009 comprising 1.4% of all reported gastrointestinal cancers. Gallbladder cancer was more common in females than males (71 vs. 29%, respectively). The age‐adjusted incidence rate was 1.4 per 100,000, significantly higher in females than males (1.7 vs. 1.0). Trend analysis showed that the incidence rate has been decreasing over the last three decades for males. However, among females, the incidence rate had decreased from 1973 to mid‐90s but has remained stable since then. Trend analysis for stage at diagnosis showed that the proportion of late‐stage cases has been increasing significantly since 2001 after a decreasing pattern since 1973. Survival has improved considerably over time, and survival is better in females than males and in Asian/Pacific Islanders than other racial groups. The highest survival was in patients who received both surgery and radiation. Trend analysis revealed a recent increase of the incidence of late‐stage gallbladder cancer. Highest survival was associated with receiving both surgery and radiation.
Transcatheter aortic valve implantation with the self‐expandable venus A‐Valve and CoreValve devices: Preliminary Experiences in China
Authors: Liao Yan‐Biao , Zhao Zhen‐Gang , Wei Xin , Xu Yuan‐Ning , Zuo Zhi‐Liang , Li Yi‐jian , Zheng Ming‐Xia , Feng Yuan , Chen Mao
Published: March 2017

Background

Transcatheter aortic valve implantation (TAVI) has been demonstrated to be an effective alternative to surgical aortic valve replacement (SAVR) in patients with aortic stenosis who are deemed high risk or inoperable. Currently, TAVI procedures in China mostly make use of the domestic Venus A‐Valve and the CoreValve; however, there is no data on their comparative performance.

Methods

Consecutive patients undergoing TAVI with the aforementioned devices were included. The outcomes were reported according to the Valve Academic Research Consortium‐2 (VARC) definitions.

Results

A total of 54 TAVI procedures were performed, 27 with the CoreValve and the other 27 with the Venus A‐Valve. An additional valve was required in 4 (14.8%) and 3 (11.1%) patients, and the VARC‐2 device success rates were 81.5 and 85.2%, respectively. The incidences of common complications were similar, except for the significantly less frequent pacemaker insertion in the Venus A‐Valve group (7.4 vs. 37.0%, P = 0.03). Within 30 days, 2 (3.7%) patients died, 1 in each group, and both had a bicuspid aortic valve (BAV). No other serious complications, such as annular rupture, coronary obstruction and aortic dissection, occurred in the 32 BAV patients treated with the Venus A‐Valve (14) or the CoreValve (18). After 2‐years of follow‐up, there was no significant difference between CoreValve group and Venus‐A group (11.1 vs. 7.4%, P = 0.64).

Conclusion

TAVI with the domestic Venus A‐Valve is feasible, safe, and can produce favorable short‐term outcomes comparable to those with the CoreValve in inoperable or high‐risk patients with tricuspid and bicuspid aortic valve stenosis. © 2017 Wiley Periodicals, Inc.
Oxidative Transformations of Biosourced Alcohols Catalyzed by Earth‐Abundant Transition Metals
Authors: Nguyen Duc Hanh , Morin Yohann , Zhang Lei , Trivelli Xavier , Capet Frédéric , Paul Sébastien , Desset Simon , Dumeignil Franck , Gauvin Régis M.
Published: March 2017

The catalytic acceptorless dehydrogenative oxidation of biosourced alcohols into carboxylic acid salts was achieved using earth‐abundant Fe and Mn complexes that feature aliphatic PNP pincer ligands in good to excellent yields. The Fe derivatives were characterized by using 57Fe NMR spectroscopy. Mn pincer catalysts are catalytically more efficient than their Fe counterparts thanks to their robustness under basic conditions. Attempts to generate aldehydes from alcohols were not successful using the Fe and Mn species, but a commercially available Ru analogue achieves this transformation selectively under very mild conditions in the presence of a large excess of acetone as a hydrogen acceptor.
Neighbouring pixel data augmentation: a simple way to fuse spectral and spatial information for hyperspectral imaging data analysis
Authors: Jamme Frédéric , Duponchel Ludovic
Published: March 2017

Hyperspectral imaging has become an essential tool in analytical chemistry. Indeed, it is used to explore complex and heterogeneous samples providing simultaneously spectral and spatial information in the acquired data cube. Many chemometric tools have been developed and optimised to extract latent features in such data structure, but it has to be said that the spatial information (ie, pixel neighbourhood) is almost not used during the data analysis framework. It is in this sense that we propose the neighbouring pixel data augmentation as a new and simple way to consider all dimensions of the cube. We will share the potential of the concept on the basis of 2 data set explorations using Raman hyperspectral imaging and deep UV synchrotron fluorescenxce microscopy. It shall be first demonstrated that more information can be extracted when neighbouring pixel data augmentation is used. Furthermore, a good behaviour against noise will be also observed.
Attracting Enantiomers: Chiral Analytes That Are Simultaneously Shift Reagents Allow Rapid Screening of Enantiomeric Ratios by NMR Spectroscopy
Authors: Storch Golo , Haas Maren , Trapp Oliver
Published: March 2017

The rapid and direct determination of enantiomeric ratios is of increasing interest due to the significantly reduced effort compared to chromatographic methods and the large number of analytes, for instance in enantioselective catalysis. Current strategies include colorimetric assays, (a)chiral solvating reagents for NMR spectroscopy and metal complexes for CD sensing. We report the determination of enantiomeric ratios based on the self‐induced diastereomeric anisochronism (SIDA) effect. Alanine derivatives that represent chiral products of enantioselective catalysis, such as the well‐established hydrogenation of dehydroamino acids, were investigated. The SIDA effect was significantly enhanced by attachment of 3,5‐dinitrobenzoyl π–π interactions sites. This simple modification enabled simultaneous determination of enantiomeric ratios and conversions by NMR spectroscopy.
Dinuclear Complexes Formed by Hydrogen Bonds: Synthesis, Structure and Magnetic and Electrochemical Properties
Authors: Granelli Matteo , Downward Alan M. , Huber Robin , Guénée Laure , Besnard Céline , Krämer Karl W. , Decurtins Silvio , Liu Shi‐Xia , Thompson Laurence K. , Williams Alan F.
Published: March 2017

The synthesis is reported of a series of homo‐ and hetero‐dinuclear octahedral complexes of the ligand 1, 1,2‐bis(1‐methyl‐benzimidazol‐2‐yl) ethanol, where the two metal centres are linked by hydrogen bonds between coordinated alcohols and coordinated alkoxides. Homonuclear divalent MIIMII, mixed‐valent MIIMIII and heteronuclear MIIM′III species are prepared. The complexes have been characterised by X‐ray crystallography and show unusually short O⋅⋅⋅O distances for the hydrogen bonds. Magnetic measurements show the hydrogen‐bond bridges can lead to ferromagnetic or antiferromagnetic coupling. The electrochemistry of the dinuclear species is significantly different from the mononuclear systems: the latter show irreversible waves in cyclic voltammograms as a result of the need to couple proton and electron transfer. The dinuclear species, in contrast, show reversible waves, which are attributed to rapid intramolecular proton transfer facilitated by the hydrogen‐bonded structure.
Cancer in adolescents and young adults: Who remains at risk of poor social functioning over time?
Authors: Husson Olga , Zebrack Bradley J. , Aguilar Christine , Hayes‐Lattin Brandon , Cole Steve
Published: March 2017

BACKGROUND

The objective of the current study was to examine social functioning among adolescents and young adults (AYAs) within the first 2 years after a cancer diagnosis and compare their scores with population norms and identify trajectories of social functioning over time and its correlates.

METHODS

A multicenter, longitudinal study was conducted among 215 AYA patients with cancer aged 14 to 39 years. A total of 141 patients completed a self‐report measure of social functioning within the first 4 months of diagnosis and again at 12 months and 24 months later.

RESULTS

AYA patients with cancer were found to have significantly worse social functioning scores around the time of diagnosis (52.0 vs 85.1; P<.001), at the 12‐month follow‐up (73.1 vs 85.1; P<.001), and at the 24‐month follow‐up (69.2 vs 85.1; P<.001) when compared with population norms. Significant improvements in social functioning from baseline to the 12‐month follow‐up were observed; however, social functioning levels remained stable thereafter. Among participants, 9% demonstrated consistently high/normal social functioning, 47% demonstrated improved social functioning, 13% were found to have worsening social functioning, and 32% demonstrated consistently low social functioning. AYA patients with cancer who had consistently low social functioning were more often off treatment at the time of follow‐up, reported more physical symptoms and higher levels of distress at baseline and follow‐up, and perceived less social support at baseline compared with the other 3 groups.

CONCLUSIONS

Although improved over time, social functioning still was found to be compromised 24 months after the primary diagnosis. Nearly one‐third of these patients remain at risk of poor social functioning. Reducing physical symptoms and psychological distress and enhancing social support by interventions during the period after treatment may potentially help these young survivors to better reintegrate into society. Cancer 2017;123:2743‐51. © 2017 American Cancer Society.
Organogels from Double‐Chained Vitamin C Amphiphilic Derivatives
Authors: Tempestini Elia , Bucci Martina , Mastromartino Vincenzo , Gori Marianna , Tanini Damiano , Ambrosi Moira , Fratini Emiliano , Capperucci Antonella , Lo Nostro Pierandrea
Published: March 2017

The syntheses and physicochemical characterization of double‐chained amphiphilic compounds obtained from vitamin C are reported: dialkanoyl‐5,6‐O‐ascorbic acid esters (Di‐ASCn, n=8, 10, and 12). The acetyl‐5‐dodecanoyl‐6‐ascorbic acid ester is synthesized and investigated for comparison. These products are quite insoluble in water and in polar solvents, although they form homogeneous dispersions in cyclohexane. Upon cooling, these dispersions turn into a gel‐like phase. Differential scanning calorimetry, FTIR spectroscopy, and small‐ and wide‐angle X‐ray scattering experiments are performed to investigate the properties of pure solids and their liquid dispersions. Di‐ASCn retain the same redox properties of the parent molecule and represent a valid candidate for the production of nanosized protective carriers for valuable guests that are sensitive to oxidative radical attack. Moreover, the contribution of the vitamin C hydroxyl group in position 5 to the overall hydration properties of single‐ and double‐chained amphiphilic derivatives is discussed.
Role of Dissolved and Molecular Oxygen on Cu and PtCu Alloy Particle Structure during Laser Ablation Synthesis in Liquids
Authors: Marzun Galina , Bönnemann Helmut , Lehmann Christian , Spliethoff Bernd , Weidenthaler Claudia , Barcikowski Stephan
Published: March 2017

The role of molecular oxygen dissolved in the solvent is often discussed as being an influential factor on particle oxidation during pulsed laser ablation in liquids. However, the formation of the particles during laser synthesis takes place under extreme conditions that enable the decomposition of the liquid medium. Reactive species of the solvent may then affect particle formation due to a chemical reaction in the reactive plasma. Experimental results show a difference between the role of dissolved molecular oxygen and the contribution from the oxygen in water molecules. Using a metallic Cu target in air‐saturated water, laser ablation led to 20.5 wt % Cu, 11.5 wt % Cu2O, and 68 wt % CuO nanoparticles, according to X‐ray diffraction results. In contrast to particles obtained in air‐saturated water, no CuO was observed in the colloid synthesized in a Schlenk ablation chamber in completely oxygen‐free water. Under these conditions, less‐oxidized nanoparticles (25 wt % Cu and 75 wt % Cu2O) were synthesized. The results show that nanoparticle oxidation during laser synthesis is mainly caused by reactive oxygen species from the decomposition of water molecules. However, the addition of molecular oxygen promotes particle oxidation. Storage of the Cu colloid in the presence of dissolved oxygen leads, due to aging, to nanostructures with a higher oxidation state than the freshly prepared colloid. The XRD pattern of the sample prepared in air‐saturated acetone showed no crystalline phases, which is possibly due to small crystallites or low particle concentration. Concentration of the particles by centrifugation showed that in the large fraction (>20 nm), even less oxidized nanoparticles (46 wt % Cu and 54 wt % Cu2O) were present, although the solubility of molecular oxygen is higher in acetone than in water. The nanoparticles in acetone were stable due to a Cu‐catalyzed graphite layer formed on their surfaces. The influence of the solvent on alloy synthesis is also crucial. Laser ablation of PtCu3 in air‐saturated water led to separated large CuO and Pt‐rich spherical nanoparticles, whereas homogeneous PtCu3 alloy nanoparticles were formed in acetone.
Functionalization of Ruthenium(II)(η6‐p‐cymene)(3‐hydroxy‐2‐pyridone) Complexes with (Thio)Morpholine: Synthesis and Bioanalytical Studies
Authors: Hanif Muhammad , Meier Samuel M. , Adhireksan Zenita , Henke Helena , Martic Sanela , Movassaghi Sanam , Labib Mahmoud , Kandioller Wolfgang , Jamieson Stephen M. F. , Hejl Michaela , Jakupec Michael A. , Kraatz Heinz‐Bernhard , Davey Curt A. , Keppler Bernhard K. , Hartinger Christian G.
Published: March 2017

Hydroxypyr(id)ones constitute an emerging platform for the design of drug molecules, owing to their favorable biocompatibility and toxicity profiles. Herein, [RuII(η6‐p‐cymene)] complexes with 3‐hydroxy‐2‐pyridinone functionalized with morpholine and thiomorpholine, as a means often used in medicinal chemistry to alter the physicochemical properties of drug compounds, are reported. The compounds underwent hydrolysis of the Ru−Cl bond and the aqua species were stable for up to 48 h in aqueous solution, as observed by 1H NMR spectroscopy and ESI‐MS. The compounds formed adducts with amino acids and proteins through cleavage of the pyridinone ligand. Binding experiments to the nucleosome core particle by means of X‐ray crystallography revealed similar reactivity and exclusive binding to histidine moieties of the histone proteins. Preliminary cyclin‐dependent kinase 2 (CDK2)/cyclin A kinase inhibitory studies revealed promising activity similar to that of structurally related organometallic compounds.
Species’ traits help predict small mammal responses to habitat homogenization by an invasive grass
Authors: Ceradini Joseph P. , Chalfoun Anna D.
Published: March 2017

Invasive plants can negatively affect native species, however, the strength, direction, and shape of responses may vary depending on the type of habitat alteration and the natural history of native species. To prioritize conservation of vulnerable species, it is therefore critical to effectively predict species’ responses to invasive plants, which may be facilitated by a framework based on species’ traits. We studied the population and community responses of small mammals and changes in habitat heterogeneity across a gradient of cheatgrass (Bromus tectorum) cover, a widespread invasive plant in North America. We live‐trapped small mammals over two summers and assessed the effect of cheatgrass on native small mammal abundance, richness, and species‐specific and trait‐based occupancy, while accounting for detection probability and other key habitat elements. Abundance was only estimated for the most common species, deer mice (Peromyscus maniculatus). All species were pooled for the trait‐based occupancy analysis to quantify the ability of small mammal traits (habitat association, mode of locomotion, and diet) to predict responses to cheatgrass invasion. Habitat heterogeneity decreased with cheatgrass cover. Deer mouse abundance increased marginally with cheatgrass. Species richness did not vary with cheatgrass, however, pocket mouse (Perognathus spp.) and harvest mouse (Reithrodontomys spp.) occupancy tended to decrease and increase, respectively, with cheatgrass cover, suggesting a shift in community composition. Cheatgrass had little effect on occupancy for deer mice, 13‐lined ground squirrels (Spermophilus tridecemlineatus), and Ord's kangaroo rat (Dipodomys ordii). Species’ responses to cheatgrass primarily corresponded with our a priori predictions based on species’ traits. The probability of occupancy varied significantly with a species’ habitat association but not with diet or mode of locomotion. When considered within the context of a rapid habitat change, such as caused by invasive plants, relevant species’ traits may provide a useful framework for predicting species’ responses to a variety of habitat disturbances. Understanding which species are likely to be most affected by exotic plant invasion will help facilitate more efficient, targeted management and conservation of native species and habitats.
Complex trait relationships between leaves and absorptive roots: Coordination in tissue N concentration but divergence in morphology
Authors: Wang Ruili , Wang Qiufeng , Zhao Ning , Yu Guirui , He Nianpeng
Published: March 2017

Leaves and absorptive roots (i.e., first‐order root) are above‐ and belowground plant organs related to resource acquisition; however, it is controversy over whether these two sets of functional traits vary in a coordinated manner. Here, we examined the relationships between analogous above‐ and belowground traits, including chemical (tissue C and N concentrations) and morphological traits (thickness and diameter, specific leaf area and root length, and tissue density) of 154 species sampling from eight subtropical and temperate forests. Our results showed that N concentrations of leaves and absorptive roots were positively correlated independent of phylogeny and plant growth forms, whereas morphological traits between above‐ and belowground organs varied independently. These results indicate that, different from plant economics spectrum theory, there is a complex integration of diverse adaptive strategies of plant species to above‐ and belowground environments, with convergent adaptation in nutrient traits but divergence in morphological traits across plant organs. Our results offer a new perspective for understanding the resource capture strategies of plants in adaptation to heterogeneous environments, and stress the importance of phylogenetic consideration in the discussion of cross‐species trait relationships.
Does the morphological fit between flowers and pollinators affect pollen deposition? An experimental test in a buzz‐pollinated species with anther dimorphism
Authors: Solís‐Montero Lislie , Vallejo‐Marín Mario
Published: March 2017

Some pollination systems, such as buzz‐pollination, are associated with floral morphologies that require a close physical interaction between floral sexual organs and insect visitors. In these systems, a pollinator's size relative to the flower may be an important feature determining whether the visitor touches both male and female sexual organs and thus transfers pollen between plants efficiently. To date, few studies have addressed whether in fact the “fit” between flower and pollinator influences pollen transfer, particularly among buzz‐pollinated species. Here we use Solanum rostratum, a buzz‐pollinated plant with dimorphic anthers and mirror‐image flowers, to investigate whether the morphological fit between the pollinator's body and floral morphology influences pollen deposition. We hypothesized that when the size of the pollinator matches the separation between the sexual organs in a flower, more pollen should be transferred to the stigma than when the visitor is either too small or too big relative to the flower. To test this hypothesis, we exposed flowers of S. rostratum with varying levels of separation between sexual organs, to bumblebees (Bombus terrestris) of different sizes. We recorded the number of visits received, pollen deposition, and fruit and seed production. We found higher pollen deposition when bees were the same size or bigger than the separation between anther and stigma within a flower. We found a similar, but not statistically significant pattern for fruit set. In contrast, seed set was more likely to occur when the size of the flower exceeded the size of the bee, suggesting that other postpollination processes may be important in translating pollen receipt to seed set. Our results suggest that the fit between flower and pollinator significantly influences pollen deposition in this buzz‐pollinated species. We speculate that in buzz‐pollinated species where floral morphology and pollinators interact closely, variation in the visitor's size may determine whether it acts mainly as a pollinator or as a pollen thief (i.e., removing pollen rewards but contributing little to pollen deposition and fertilization).
Environmental heterogeneity does not affect levels of phenotypic plasticity in natural populations of three Drosophila species
Authors: Manenti Tommaso , Sørensen Jesper G. , Loeschcke Volker
Published: March 2017

Adaptation of natural populations to variable environmental conditions may occur by changes in trait means and/or in the levels of plasticity. Theory predicts that environmental heterogeneity favors plasticity of adaptive traits. Here we investigated the performance in several traits of three sympatric Drosophila species freshly collected in two environments that differ in the heterogeneity of environmental conditions. Differences in trait means within species were found in several traits, indicating that populations differed in their evolutionary response to the environmental conditions of their origin. Different species showed distinct adaptation with a very different role of plasticity across species for coping with environmental changes. However, geographically distinct populations of the same species generally displayed the same levels of plasticity as induced by fluctuating thermal regimes. This indicates a weak and trait‐specific effect of environmental heterogeneity on plasticity. Furthermore, similar levels of plasticity were found in a laboratory‐adapted population of Drosophila melanogaster with a common geographic origin but adapted to the laboratory conditions for more than 100 generations. Thus, this study does not confirm theoretical predictions on the degree of adaptive plasticity among populations in relation to environmental heterogeneity but shows a very distinct role of species‐specific plasticity.
Switching among natal and auxiliary hosts increases vulnerability of Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) to insecticides
Authors: Saeed Qamar , Saeed Shafqat , Ahmad Faheem
Published: March 2017

The role of insecticidal application and host plant resistance in managing Spodoptera exigua has been well documented, but the effect of different host plants, on which the pest cycles its population in the field, has seldom been investigated. Therefore, we have studied the vulnerability of S. exigua against commonly used insecticides (cypermethrin, chlorpyrifos, lufenuron, and emamectin benzoate) with different mode of actions when it switches its generations from natal to auxiliary hosts and vice versa. Different field populations being established on different host plants including castor, cauliflower, cotton, okra, and spinach were collected and reared in the laboratory before insecticidal bioassays. The role of larval diet and host plant switching on their response to tolerate applied insecticides was studied using leaf‐dip bioassay methods. Host switching demonstrated a significant role in altering the vulnerability of S. exigua populations to tested insecticides. Spodoptera exigua sourced from castor, when switched host to okra and spinach, exhibited 50% higher mortality when treated with emamectin benzoate. This trend in mortality was consistent upon complete host switch cycle (natal—auxiliary—natal host). However, the highest increase (92%) in vulnerability was recorded when the larvae were shifted to spinach from cotton. In general, chlorpyrifos and lufenuron had highest efficacies in terms of larval mortality. The findings of present studies provide insights to a better understanding the behavior of polyphagous pests and the role of different host plants in altering the susceptibility of these pests against applied insecticides. Ultimately the results warrant that due consideration should be given to cropping patterns and time of host switching by pest population during planning and executing chemical control.
Environmental indicators reflective of road design in a forested landscape
Authors: Neher Deborah A. , Williams Kristin M. , Lovell Sarah Taylor
Published: March 2017

Roads cause both chemical and physical disturbance at the time of creation and through the maintenance of the road. However, none have fully considered the extent of above‐ and below‐ground impacts related to roads. Our study seeks to fill this gap with three objectives: (1) quantify differences in the nematode community by road‐use intensity, (2) estimate distance of environmental impact of roads using nematode community indices, and (3) relate nematode communities to abiotic soil and above‐ground plant communities for a relatively comprehensive environmental assessment of the spatial footprint of roads on the landscape. Soil and plant samples were co‐located at six distances from the road edge (shoulder, sideslope, ditch, backslope, 10 m from forest edge, and 50 m from road crown) for each of 10 transects perpendicular to each of three road types (highways, two‐lane paved, and gravel). There were differences in all nematode community measures based upon distance as a main effect, correlating with patterns of plant communities. Nematode community index values reflect increased disturbance closer to the road, particularly at the shoulder, with later ecological succession and a shift in the decomposer food web with increased distance from the road and in reference forest sites. In contrast, chemical properties of soil were influenced more by road type and the two‐way interaction of road type and topography. Salt concentrations were greatest by two‐lane paved roads, while heavy metal concentrations were greatest near highway roads. This study is one of the most comprehensive assessments of environmental impact by roads, providing data for accurate transportation system models. The results suggest that conscious design and management of the forest buffer and intentional inclusion of a ditch as a roadside feature may minimize pollutant movement and protect surrounding landscapes.
Effect of consumer loss on resource removal depends on species‐specific traits
Authors: Hodapp Dorothee , Hillebrand Helmut
Published: March 2017

Negative effects of species loss on ecosystem functioning within and across trophic levels have been demonstrated across systems and organism groups. Recent meta‐analyses showed that lower levels of consumer diversity lead to a reduction in resource removal. The strength of these effects seems to strongly depend on species identity, that is, species‐specific traits, resulting in a variety of consumer interactions ranging from facilitating to strongly antagonistic effects. For a general test of trait‐based effects of species loss, we conducted a meta‐analysis on resource experiments including two consumer species. We calculated effect sizes of losing one of the two species, and related these to variables describing species' traits and experimental design. Our results show that loss of one species on average reduces resource removal supporting the hypothesis that loss of certain species‐specific traits cannot fully be compensated for by biomass increases of the remaining consumer. However, the investigation of various consumer traits including body size did not allow for generalizations on the effect of loss of a certain consumer trait on resource removal.
What if plant functional types conceal species‐specific responses to environment? Study on arctic shrub communities
Authors: Saccone Patrick , Hoikka Kristiina , Virtanen Risto
Published: March 2017

Plant functional types (PFT) are increasingly used to outline biome‐scale plant–environment relationship and predict global change effects on community structure. However, the potentials and limitations of the PFT approach have to be tested as they can be less sensitive than trait‐based or species‐level approaches. Here, we compare the responses of deciduous‐evergreen shrub PFTs and species to gradual snow‐related environmental conditions by also considering effects of aboveground architectural traits and neighboring shrubs. Five deciduous species and four evergreen dwarf shrub species were transplanted to be exposed to four levels of winter snow cover across mesotopographic gradients in northern Fennoscandian tundra. The survival and growth of individually tagged shoots were monitored over one year, and the change in cover of shrubs was monitored over four years. Evergreen species showed higher resistance to environmental severity and generally benefitted from higher abundance of neighboring shrubs. Deciduous species exhibited negligible to drastic responses to snow thickness and neighboring shrubs tended to have a negative effect on their performance and survival. Tall shoots of deciduous shrubs survived poorly under the thinnest snow cover. Overall, deciduous and evergreen PFTs showed modest differences in their performances along the gradient. Our results show that deciduous‐evergreen leaf phenology categories predict shrub responses to changing environmental conditions only to a limited extent. Our findings highlight strong species‐specific responses especially among deciduous shrubs, and a differential role of plant–plant interactions for shrubs. Our results emphasize that distribution patterns of arctic‐alpine shrubs and shrub community responses to altered snow regimes depend on species‐level plant functional attributes, species interactions and species‐specific sensitivities to environmental severity.
(E)‐1,2‐Bis(3,5‐dinitro‐1H‐pyrazol‐4‐yl)diazene – Its 3D Potassium Metal–Organic Framework and Organic Salts with Super‐Heat‐Resistant Properties
Authors: Zhang Man , Fu Wei , Li Chuan , Gao Huiqi , Tang Liwei , Zhou Zhiming
Published: March 2017

(E)‐1,2‐Bis(3,5‐dinitro‐1H‐pyrazol‐4‐yl)diazene (H2NPA, 1) and its energetic salts, which are a series of new, energetic, highly heat‐resistant, dense explosives, were synthesized. The explosives contain four nitro groups and an azo‐bridged framework and were characterized by 1H and 13C NMR (in some cases 15N NMR) spectroscopy, IR spectroscopy, and elemental analysis. The crystal structures of K2NPA (a three‐dimensional metal–organic framework, 3D MOF) and the guanidinium salt 4 were determined by single‐crystal X‐ray diffraction, and their properties (density, thermal stability, and sensitivity towards impact and friction) were investigated. The detonation properties were evaluated from the measured density and calculated heat of formation by the EXPLO5 v6.01 program. All of the salts exhibit thermal stabilities with decomposition temperatures ranging from 156 to 315 °C, high densities (1.70–2.15 g cm–3), high detonation velocities (8224–9083 m s–1), and high positive heats of formation (45.7–1040.1 kJ mol–1). The obtained 3D metal–organic framework explosive K2NPA combines exceptional thermal stability (Td = 315 °C) with a high density (d = 2.15 g cm–3) and possesses ideal calculated detonation velocity (vD = 8275 m s–1) and pressure (PCJ = 31.1 GPa) values. Moreover, its suitable impact sensitivity (IS) of 1.5 J and friction sensitivity (FS) of 60 N make K2NPA an outstanding, highly heat‐resistant, green primary explosive. The guanidinium salt 4 also exhibits a high thermal stability (Td = 304 °C) that is superior to that of HMX, insensitivity to impact (IS > 40 J) and friction (FS > 360 N) comparable to those of 1,3,5‐triamino‐2,4,6‐trinitrobenzene (TATB), and a high detonation performance (vD = 8391 m s–1).
Rapid Ultrasound‐Assisted Synthesis of Mesoporous Manganese Oxides for Low‐Concentration NO Elimination with Superior Water‐Resistance
Authors: Du Yanyan , He Feng , Hua Zile , Wu Zhijian , Li Mengli , Li Jiusheng , Huang Keke , Shi Jianlin
Published: March 2017

Through a room‐temperature ultrasound‐assisted redox process, mesoporous manganese oxides were synthesized in short reaction times of 3–9 h. At room temperature, the resultant materials showed superior performance for the elimination of low‐concentration NO (10 ppm). Specifically, under humid conditions (50–90 % relative humidity), 97 % NO removal efficiency was obtained over 110 h without deactivation. Synergetic effects between Mn2+, Mn3+, and Mn4+ ions were proposed to explain the oxidation of NO to NO2 on the surface of the catalyst. Density functional theory (DFT) calculations indicated that water molecules strengthen the chemisorption of NO2 on manganese oxide (001) owing to a much higher adsorption energy. As a result, the probability of the reaction between NO2 and H2O increases, and the formation of volatile nitric acid ensures that the catalytically active sites are always available.
Redox Center Modification of Lapachones towards the Synthesis of Nitrogen Heterocycles as Selective Fluorescent Mitochondrial Imaging Probes
Authors: dos Santos Fabíola S. , Dias Gleiston G. , de Freitas Rossimiriam P. , Santos Lucas S. , de Lima Guilherme F. , Duarte Hélio A. , de Simone Carlos A. , Rezende Lidia M. S. L. , Vianna Monique J. X. , Correa José R. , Neto Brenno A. D. , da Silva Júnior Eufrânio N.
Published: March 2017

We describe herein a synthetic strategy for the synthesis of new fluorescent imidazole and phenazine derivatives synthesized from lapachol, a naturally occurring naphthoquinone isolated from Tabebuia species (ipê tree). The photophysical properties and computational details of these compounds have been studied, aiming at gaining a complete understanding of the potential of these derivatives as probes capable of staining mitochondria selectively. Cell imaging experiments proved the capacity of the imidazole derivatives as selective fluorescent mitochondrial imaging probes. These heterocycles present the same staining patterns as MitoTracker Red, corroborating the potential of these compounds as new mitochondria markers permeable to the cell membrane.