bluuebunny/crossref_metadata_2025_split huggingface dataset:
New polymyxin derivatives that display improved efficacy in animal infection models as compared to polymyxin B and colistin
Authors: Vaara Martti 
Published: February 2018

AbstractPolymyxin B and colistin (polymyxin E) are bactericidal pentacationic lipopeptides that act specifically on Gram‐negative bacteria, first by disrupting their outermost permeability barrier, the outer membrane (OM), and then damaging the cytoplasmic membrane. The discovery of both polymyxin B and colistin was published independently by three laboratories as early as in 1947. They were subsequently used in intravenous therapy. Unfortunately, they also exhibit significant and dose‐limiting nephrotoxicity. Therefore, polymyxins were reserved as agents of last‐line defense. The emergence of extremely multiresistant strains has now forced clinicians to reinstate polymyxins in the therapy of severe infections. However, the current dosage regimens lead to insufficient drug concentrations in serum and clinicians have been advised to use larger doses, which further increases the risk of nephrotoxicity. Very recently, the interest in developing better tolerated and more effective polymyxins has grown. This review focuses on describing four development programs that have yielded novel derivatives that are more effective than the old polymyxins in animal infection models. Compounds from three programs are superior to the old polymyxins in the rodent lung infection model with Acinetobacter baumannii and/or Pseudomonas aeruginosa. One of them is also more effective than polymyxin B in A. baumannii mouse thigh infection. The fourth program includes compounds that are approximately tenfold more effective in Escherichia coli murine pyelonephritis than polymyxin B.
Translational Chemistry Meets Gluten‐Related Disorders
Authors: Lammers Karen M. , Herrera Maria G. , Dodero Veronica I. 
Published: February 2018

AbstractGluten‐related disorders are a complex group of diseases that involve the activation of the immune system triggered by the ingestion of gluten. Among these, celiac disease, with a prevalence of 1 %, is the most investigated, but recently, a new pathology, named nonceliac gluten sensitivity, was reported with a general prevalence of 7 %. Finally, there other less‐prevalent gluten‐related diseases such as wheat allergy, gluten ataxia, and dermatitis herpetiformis (with an overall prevalence of less than 0.1 %). As mentioned, the common molecular trigger is gluten, a complex mixture of storage proteins present in wheat, barley, and a variety of oats that are not fully degraded by humans. The most‐studied protein related to disease is gliadin, present in wheat, which possesses in its sequence many pathological fragments. Despite a lot of effort to treat these disorders, the only effective method is a long‐life gluten‐free diet. This Review summarizes the actual knowledge of gluten‐related disorders from a translational chemistry point of view. We discuss what is currently known from the literature about the interaction of gluten with the gut and the critical host responses it evokes and, finally, connect them to our current and novel molecular understanding of the supramolecular organization of gliadin and the 33‐mer gliadin peptide fragment under physiological conditions.
The Incidental Fertility Effects of School Condom Distribution Programs
Authors: Buckles Kasey S. , Hungerman Daniel M. 
Published: February 2018

AbstractWhile the fertility effects of improving teenagers’ access to contraception are theoretically ambiguous, most empirical work has shown that access decreases teen fertility. In this paper, we consider the fertility effects of access to condoms—a method of contraception not considered in prior work. We exploit variation across counties and across time in teenagers’ exposure to condom distribution programs in schools. We find that access to condoms in schools increases teen fertility by about 12 percent. The results suggest that the effects of condom access varied significantly across different programs; the positive fertility estimates are driven by communities where condoms are provided without mandated counseling. Programs that mandated counseling have zero or negative fertility effects, but estimates on these counties are less robust across specifications.
Association of Protein Kinase B (AKT) DNA Hypermethylation with Maintenance Atypical Antipsychotic Treatment in Patients with Bipolar Disorder
Authors: Burghardt Kyle J. , Seyoum Berhane , Dass Sabrina E. , Sanders Elani , Mallisho Abdullah , Yi Zhengping 
Published: February 2018

Study ObjectiveAtypical antipsychotics cause insulin resistance that leads to an increased risk of diabetes mellitus and cardiovascular disease. Skeletal muscle is the primary tissue for uptake of glucose, and its dysfunction is considered one of the primary defects in the development of insulin resistance. Protein kinase B (AKT) plays an important role in overall skeletal muscle health and glucose uptake into the muscle. The objective of this study was to measure AKT isoform–specific gene methylation differences in the skeletal muscle of patients with bipolar disorder treated with atypical antipsychotic or mood stabilizer maintenance therapy.DesignCross‐sectional observational study.SettingClinical research services center at an academic center.PatientsThirty patients with a confirmed diagnosis of bipolar disorder who were treated with either an atypical antipsychotic (16 patients) or mood stabilizer (14 patients) at a consistent dose for at least 3 months.InterventionsA fasting skeletal muscle biopsy was performed in the vastus lateralis in each patient. Patients also underwent fasting blood sample collection and a standard 75‐g oral glucose tolerance test.Measurements and Main ResultsSkeletal muscle DNA methylation near the promoter region for three genes, AKT1, AKT2, and AKT3, was measured by methylation‐sensitive high‐resolution melting. Gene methylation was analyzed based on atypical antipsychotic versus mood stabilizer maintenance therapy. Associations between gene methylation, insulin resistance, and glucose tolerance were also analyzed. In patients treated with atypical antipsychotics, AKT1 and AKT2 methylation was increased compared with patients treated with mood stabilizers (p=0.03 and p=0.02, respectively). In addition, for patients receiving atypical antipsychotics, a positive trend for AKT2 hypermethylation with increasing insulin resistance was observed, whereas for patients receiving mood stabilizers, a trend for decreased AKT2 methylation with increasing insulin resistance was observed.ConclusionOverall, our findings suggest that the AKT gene is differentially methylated in the skeletal muscle of patients taking atypical antipsychotics or mood stabilizer maintenance therapy. These results may direct future approaches to reduce the harmful adverse effects of atypical antipsychotic treatment.
Antifungal constituents of the plant family Amaryllidaceae
Authors: Nair Jerald J. , van Staden Johannes 
Published: February 2018

Globalization, the modern lifestyle, immuno‐suppressive agents, invasive surgical procedures, the loss of efficacies of existing drugs, and multidrug resistance are some of the factors used to explain the rise in fungal infections in recent years. Significant advances have been made in attempts to replace existing antifungal schedules, especially with synthetic targets. The identification of other platforms for drug discovery is now entrenched in research programs across the globe. Plants offer significant benefits owing to their numerical superiority, exceedingly broad chemical basis and appealing sustainability characteristics. Furthermore, plants have a long and rich historical association with traditional approaches towards fungal diseases. These have in numerous instances served as markers in the bioassay‐guided identification of the active constituents. Although the plant family Amaryllidaceae is conventionally associated with cancer and motor‐neuron disease chemotherapies, around 30 of its species have been examined for antifungal activities with microgram per millilitre inhibitory activities detected in several instances. This review focuses on the nearly 40 constituents from the family, mainly isoquinoline alkaloids, which have been screened against around 50 fungal pathogens. Encouragingly, microgram per millilitre growth inhibitory activities were applicable for several of the compounds with a minimum inhibitory concentration of 4 μg/ml seen to be the lowest.
System and path planning algorithm for low‐kV X‐ray free‐form surface irradiation
Authors: Rothfuss Andreas , Oesterle Oliver , Bürgy Daniel , Nwankwo Charles , Schneider Frank , van Poelgeest Auguste , Wenz Frederik , Stallkamp Jan , Clausen Sven 
Published: February 2018

AbstractObjective: Intraoperative radiotherapy (IORT) after surgical resection using a low‐kV‐X‐ray source is a proven method used in cancer treatment. However, the shape and size of the targeted surface area are limited to the size of the available applicators. This can lead to nonconformal and therefore suboptimal treatment for many patients.Methods: A system is proposed comprising an X‐ray source with an applicator for surface irradiation mounted on a robotic arm. This is controlled by an algorithm designed for planning the required continuous path, enabling irradiation of any desired shape with a controlled dose distribution.Results: The system is shown to be capable of irradiating areas composed of rectangles on a flat surface with a homogeneity index of less than 7% inside the targeted area.Conclusion: The presented results demonstrate the potential of the proposed setup to eliminate the current limitations, leading to better treatment of patients.
A closed‐loop nonlinear control and sliding mode estimation strategy for fluid flow regulation
Authors: Kidambi Krishna Bhavithavya , Ramos‐Pedroza Natalie , MacKunis William , Drakunov Sergey V. 
Published: February 2018

SummaryNovel sliding mode observer (SMO) and robust nonlinear control methods are presented, which are shown to achieve finite‐time state estimation and asymptotic regulation of a fluid flow system. To facilitate the design and analysis of the closed‐loop active flow control (AFC) system, proper orthogonal decomposition–based model order reduction is utilized to express the Navier‐Stokes partial differential equations as a set of nonlinear ordinary differential equations. The resulting reduced‐order model contains a measurement equation that is in a nonstandard mathematical form. This challenge is mitigated through the detailed design and analysis of an SMO. The observer is shown to achieve finite‐time estimation of the unmeasurable states of the reduced‐order model using direct sensor measurements of the flow field velocity. The estimated states are utilized as feedback measurements in a closed‐loop AFC system. To address the practical challenge of actuator bandwidth limitations, the control law is designed to be continuous. A rigorous Lyapunov‐based stability analysis is presented to prove that the closed‐loop flow estimation and control method achieves asymptotic regulation of a fluid flow field to a prescribed state. Numerical simulation results are also provided to demonstrate the performance of the proposed closed‐loop AFC system, comparing 2 different designs for the SMO.
MoS2‐QD‐Based Dual‐Model Photoluminescence Sensing Platform for Effective Determination of Al3+ and Fe3+ Simultaneously in Various Environment
Authors: Wu Qian , Wang Xiaojie , Jiang Yingnan , Sun Weiyi , Wang Chuanxi , Yang Minghui , Zhang Chi 
Published: February 2018

AbstractThe development of a sensitive sensing platform with multiple ions recognition ability in various environment is of great importance. In this paper, cysteine‐functionalized MoS2 quantum dots (Cys‐MoS2 QDs) with stable fluorescence are synthesized by a simple amidation reaction. The resultant Cys‐MoS2 QDs show good dispersion in aqueous solution and blue emission (λem= 428 nm) with a quantum yield (∼5%). The Cys‐MoS2 QDs drastically have improved the surface chemical reactivities, which exhibit sensitive and selective “turn‐on” response to Al3+ and “turn‐off” response to Fe3+ simultaneously. Furthermore, we testify the feasibility of applying this fluorescent probe for real sample analysis through the detection of Al3+ and Fe3+ ions in lake water and tap water. Moreover, using HeLa cells as the model, the resultant nanosensor is demonstrated to monitor Al3+ and Fe3+ ions in living cells. Thus, resultant Cys‐MoS2 QDs could be used as a “turn‐on” and “turn‐off” dual‐model photoluminescence sensing platform for effective determination of Al3+ and Fe3+ simultaneously in various environment.
New Heteropolycyclic Structures for Fluoride Anion Sensing by Naked‐Eye Visualization
Authors: Zhu Lei , Wen Ying , Liu Haoran , Zeng Zebing , Zhao Jingzhe , Jiang Jianhui , Miao Shaobin 
Published: February 2018

AbstractFluoride anion (F−) plays an important and fundamental role in chemical, biological, pathological, and environmental processes. It is highly desired to develop new methods for facial and efficient F− detection. Herein we present the synthesis and characterization of two effective fluoride ion probes and their selective F− sensing by naked‐eye visualization. A N‐heteroannelated anthraquinone derivative, compound I, was prepared by a cyclocondensation reaction of 1,2‐diaminoanthraquinone with 1,6‐bis(triisopropylsilyl)‐hexa‐l,5‐diyne‐3,4‐dione. Compound I was treated with malononitrile in the presence of Lehnert reagent to afford an HCl adduct, compound II, and an aza‐polycyclic aromatic compound III. All three compounds were characterized crystallographically and were studied photochemically. Similarly, 2,3‐diamino‐1,4‐anthraquinone reacted with 1,6‐bis(triisopropylsilyl)‐hexa‐l,5‐diyne‐3,4‐dione to afford compound IV, which reacted with malononitrile in the presence of Lehnert reagent to yield compound V. Compounds III and V are sensitive and selective probes for the detection of F− with significant color changes. The detection by naked eye visualization is rapid and facile, showing both compounds are potential probes for fluoride ion sensing.
pH‐Triggered 4,4′,4′′,4′′′‐(Ethene‐1,1,2,2‐tetrayl)tetrakis(N,N‐diethylaniline) with Aggregation‐Induced Emission (AIE) for Ablation of Cancer Cells
Authors: Yun Li Qiao , Yong Yang Zhan , Ting Su Wan , Yu Chen Dian , Wen Yang Gao , Feng Zou Deng 
Published: February 2018

AbstractIt is of great significance to develop compounds that can be soluble or dispersible in water and simultaneously remain high fluorescent in aqueous media. Compounds with aggregation induced emission (AIE) have a great potential as cell imaging agents. In this paper, 4,4′,4′′,4′′′‐(ethene‐1,1,2,2‐tetrayl)tetrakis(N,N‐diethylaniline) (denoted as ETTDA) with AIE was designed and prepared. DSPE‐PEG‐2000 (1,2‐dipalmitoyl‐sn‐glycero‐3‐phosphoethanolamine‐N‐(polyethylene glycol)‐Folate (sodium salt)‐2000) coated ETTDA nanoparticles (NPs) were used for treatment of four different kinds of cancer cells (HCT‐116 (human colon cancer cell), A549 (human caucasian lung carcinoma), Hela (human cervical cancer cells) and A2780 (ovarian carcinoma cells)) and cytotoxicity investigation shows it is highly sensitive to Hela, moderate sensitive to A549 and A2780 but low sensitive to HCT‐116. Furthermore, cell migration of ETTDA nanoparticles (NPs) on Hela shows that ETTDA NPs are capable of inhibiting the migration of Hela in vitro, indicating its potential ability to interfere with the transfer of tumor in vivo.
Hybrid NiCo2O4‐NiCo2S4 Nanoflakes as High‐Performance Anode Materials for Lithium‐Ion Batteries
Authors: Raj Shipra , Dong Yifan , Kar Pradip , Mai Liqiang , Jin Song , Roy Poulomi 
Published: February 2018

AbstractThe hybrid electrode with the combination of NiCo2O4 of inverse spinel structure and more conducting NiCo2S4 of normal spinel structure has been developed for next generation Li‐ion batteries. The hybrid nanostructures with the accessibility of both NiCo2O4 as well as NiCo2S4 showed almost 2‐fold better performance compared to pristine NiCo2O4. Apart from the doubled performance for hybrid materials, a significant cycling stability with 91.6% coulombic efficiency was achieved over 200 cycles. Such a high storage performance for the hybrid materials can be attributed not only to their normal spinel/inverse spinel combination, but also to the binder‐free direct deposition of materials on to the conductive 3D open Ni‐frame resulting high electrical conductivity and easy ionic diffusion.
Novel 1,2,3‐Triazole‐Functionalized 1,2‐Benzothiazine 1,1‐Dioxide Derivatives: Regioselective Synthesis, Biological Evaluation and Docking Studies
Authors: Swaroop Desireddy Krishna , Kumar Nagiri Ravi , Ratnakarreddy Kuchukulla , Raja Gopoju , Srigiridhar Kotamraju , Poornachandra Yedla , Kumar Chityal Ganesh , Babu Nanubolu Jagadeesh , Kumar Gunda Shravan , Narsaiah Banda 
Published: February 2018

AbstractA series of novel 1,2‐benzothiazine‐1,1‐dioxide derivatives (Z)‐3‐hydroxy‐1‐(4‐hydroxy‐2‐methyl‐1,1‐dioxido‐2H‐benzo[e][1, 2]thiazin‐3‐yl)‐3‐phenyl substituted prop‐2‐en‐1‐one (6 a‐d) were synthesized starting from sodium salt of saccharin 1 in series of steps via 3‐acetyl‐2‐methyl‐1,1‐dioxido‐2H‐benzo[e][1, 2]thiazin‐4‐yl substituted benzoates (5 a‐d). Compound 6 e was obtained alternately from 1‐(4‐Hydroxy‐2‐methyl‐1,1‐dioxo‐1,2‐dihydro‐1λ6‐benzo[e][1, 2]thiazin‐3‐yl)‐ethanone (4). Compounds 6 a‐e were further reacted with aromatic azides to form (4‐hydroxy‐2‐methyl‐1,1‐dioxido‐2H‐benzo[e][1, 2]thiazin‐3‐yl)(1‐substitutedphenyl)‐5‐ substituted pheny or methyl‐1H‐1,2,3‐triazol‐4‐yl)methanone derivatives (7 a‐o) by regioselective cyclization. All the compounds were evaluated for anti‐inflammatory and anti‐cancer activities. Compounds 5 a‐b, 6 a‐b, 7 a, 7 c‐d, 7 i and 7 k‐l which showed significant anti‐inflammatory activity at micro molar concentration have been identified. Also screened for cytotoxic activity against four human cancer cells and one normal cell such as prostate cancer (PC‐3), breast adenocarcinoma (MDA‐MB‐231), liver hepatocellular carcinoma (Hep G2), cervical cancer (HeLa) and normal umbilical vein endothelial cell (HUVEC). Compounds 6 a, 7 g, 7 h and 7 k have been identified as promising candidates. Further, anti‐inflammatory activity is also validated by docking studies and compounds 5 a, 5 b and 7 d found to show good interactions when docked with IL‐1β signaling complex.
Synergistic Nanotubular Copper‐Doped Nickel Catalysts for Hydrogen Evolution Reactions
Authors: Sun Qiangqiang , Dong Yujuan , Wang Zenglin , Yin Shiwei , Zhao Chuan 
Published: February 2018

AbstractDeveloping highly active electrocatalysts with low cost and high efficiency for hydrogen evolution reactions (HERs) is of great significance for industrial water electrolysis. Herein, a 3D hierarchically structured nanotubular copper‐doped nickel catalyst on nickel foam (NF) for HER is reported, denoted as Ni(Cu), via facile electrodeposition and selective electrochemical dealloying. The as‐prepared Ni(Cu)/NF electrode holds superlarge electrochemical active surface area and exhibits Pt‐like electrocatalytic activity for HER, displaying an overpotential of merely 27 mV to achieve a current density of 10 mA cm−2 and an extremely small Tafel slope of 33.3 mV dec−1 in 1 m KOH solution. The Ni(Cu)/NF electrode also shows excellent durability and robustness in both continuous and intermittent bulk water electrolysis. Density functional theory calculations suggest that Cu substitution and the formation of NiO on the surface leads to more optimal free energy for hydrogen adsorption. The lattice distortion of Ni caused by Cu substitution, the increased interfacial activity induced by surface oxidation of nanoporous Ni, and numerous active sites at Ni atom offered by the 3D hierarchical porous structure, all contribute to the dramatically enhanced catalytic performance. Benefiting from the facile, scalable preparation method, this highly efficient and robust Ni(Cu)/NF electrocatalyst holds great promise for industrial water–alkali electrolysis.
Retracted: Dual Effects of Nanostructuring and Oxygen Vacancy on Photoelectrochemical Water Oxidation Activity of Superstructured and Defective Hematite Nanorods
Authors: Wang Lei , Marcus Kyle , Huang Xiaojuan , Shen Zhiqiang , Yang Yang , Bi Yingpu 
Published: February 2018

AbstractAn Ar atmospheric treatment is rationally used to etch and activate hematite nanoflakes (NFs) as photoanodes toward enhanced photoelectrochemical water oxidation. The formation of a highly ordered hematite nanorods (NRs) array containing a high density of oxygen vacancy is successfully prepared through in situ reduction of NFs in Ar atmosphere. Furthermore, a hematite (104) plane and an iron suboxide layer at the absorber/back‐contact interface are formed. The material defects produced by a thermal oxidation method can be critical for the morphology transformation from 2D NFs to 1D NRs. The resulting hematite NR photoanodes show high efficiency toward solar water splitting with improved light harvesting capabilities, leading to an enhanced photoresponse due to the artificially formed oxygen vacancies.
A Flexible Stretchable Hydrogel Electrolyte for Healable All‐in‐One Configured Supercapacitors
Authors: Guo Ying , Zheng Kaiqiang , Wan Pengbo 
Published: February 2018

AbstractThe development of integrated high‐performance supercapacitors with all‐in‐one configuration, excellent flexibility and autonomously intrinsic self‐healability, and without the extra healable film layers, is still tremendously challenging. Compared to the sandwich‐like laminated structures of supercapacitors with augmented interfacial contact resistance, the flexible healable integrated supercapacitor with all‐in‐one structure could theoretically improve their interfacial contact resistance and energy densities, simplify the tedious device assembly process, prolong the lifetime, and avoid the displacement and delamination of multilayered configurations under deformations. Herein, a flexible healable all‐in‐one configured supercapacitor with excellent flexibility and reliable self‐healing ability by avoiding the extra healable film substrates and the postassembled sandwich‐like laminated structures is developed. The healable all‐in‐one configured supercapacitor is prepared from in situ polymerization and deposition of nanocomposites electrode materials onto the two‐sided faces of the self‐healing hydrogel electrolyte separator. The self‐healing hydrogel film is obtained from the physically crosslinked hydrogel with enormous hydrogen bonds, which can endow the healable capability through dynamic hydrogen bonding. The assembled all‐in‐one configured supercapacitor exhibits enhanced capacitive performance, good cycling stability, reliable self‐healing capability, and excellent flexibility. It holds broad prospects for obtaining various flexible healable all‐in‐one configured supercapacitors for working as portable energy storage devices in wearable electronics.