bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancing the Antimicrobial Activity of Alamethicin F50/5 by Incorporating N‐terminal Hydrophobic Triazole Substituents.
Authors: Das Sanjit , Ben Haj Salah Khoubaib , Wenger Emmanuel , Martinez Jean , Kotarba Jules , Andreu Vanessa , Ruiz Nicolas , Savini Filippo , Stella Lorenzo , Didierjean Claude , Legrand Baptiste , Inguimbert Nicolas
Published: September 2017

A simple and efficient strategy is proposed to significantly improve the antibacterial activity of peptaibols and other antimicrobial peptides by N‐terminal capping with 1,2,3‐triazole bearing various hydrophobic substituents on C‐4. Such N‐terminal insertions on alamethicin F50/5 could enhance its antimicrobial activity on Gram‐positive bacteria without modification of its overall three‐dimensional structure. Although the native peptide and its analogues shared comparable helical contents, the crystal structure of one of the most active derivative showed a local slight distortion of the N‐terminal extremity, which was also observed in solution using NMR spectroscopy. Importantly, fluorescence studies showed that the N‐capped derivatives had increased affinity for liposomes, which may indicate they interacted more strongly with the bacterial membrane than alamethicin F50/5.
Formation and Structural Diversity of Organo‐Functionalized Tin–Silver Selenide Clusters
Authors: Rinn Niklas , Guggolz Lukas , Gries Katharina , Volz Kerstin , Senker Jürgen , Dehnen Stefanie
Published: September 2017

When reacting the organic functionalized tin selenide clusters [(SnR1)3Se4Cl] (A, R1=CMe2CH2C(O)Me) or [(SnR1)4Se6] (B) with (SiMe3)2Se and [Ag(PPh3)3Cl] at −78 °C in CH2Cl2, a microcrystalline intermediate (compound 1) precipitates, which was investigated by magic angle spinning (MAS) NMR spectroscopy, powder X‐ray diffraction (PXRD), energy dispersive X‐ray (EDX) spectroscopy, and quantum chemistry calculations, to derive information about its composition and structure. Compound 1 re‐dissolves under reorganization into the organo‐functionalized Ag/Sn/Se cluster compound [Ag6(μ6‐Se)(Ag8Se12){(R1Sn)2Se2}6] (2), or the mixed‐valence cluster [(AgPPh3)2(SnIICl)2Se2{(R1SnIV)2Se2}2] (3), depending on the presence or the exclusion of daylight, respectively. The addition of N2H4⋅H2O to a solution of 1 yields selectively [Ag7(μ7‐Se)(Ag7Se12){(R2Sn)2Se2}6] (4, R2=CMe2CH2C(N2H2)Me), the Ag/Sn/Se core of which is isomeric to that of 2. 2–4 were characterized by X‐ray diffraction. NMR spectroscopic studies on solutions of 1 indicate the co‐existence of different species.
Magnetic Nanotransducers in Biomedicine
Authors: Grillone Agostina , Ciofani Gianni
Published: September 2017

Owing to their abilities to identify diseased conditions, to modulate biological processes, and to control cellular activities, magnetic nanoparticles have become one of the most popular nanomaterials in the biomedical field. Targeted drug delivery, controlled drug release, hyperthermia treatment, imaging, and stimulation of several biological entities are just some of the several tasks that can be accomplished by taking advantage of magnetic nanoparticles in tandem with magnetic fields. The huge interest towards this class of nanomaterials arises from the possibility to physically drive their spatiotemporal localization inside the body, and to deliver an externally applied stimulation at a target site. They in fact behave as actual nanotransducers, converting energy stemming from the external magnetic field into heat and mechanical forces, which act as signals for therapeutic processes such as hyperthermia and controlled drug release. Magnetic nanoparticles are a noninvasive tool that enables the remote activation of biological processes, besides behaving as formidable tracers for different imaging modalities, thus allowing to simultaneously carry out diagnosis and therapy. In view of all this, owing to their multifunctional and multitasking nature, magnetic nanoparticles are already one of the most important nanotechnological protagonists in medicine and biology, enabling an actual theranostic approach in many pathological conditions. In this Concept, we first provide a brief introduction on some physical properties of magnetic materials and on important features that determine the physical properties of magnetic nanoparticles. Thereafter, we will consider some major biomedical applications: hyperthermia, drug delivery/release, and nanoparticle‐mediated control of biological processes, even at subcellular level.
Mechanistic Studies on the Role of [CuII(CO3)n]2−2n as a Water Oxidation Catalyst: Carbonate as a Non‐Innocent Ligand
Authors: Mizrahi Amir , Maimon Eric , Cohen Haim , Kornweitz Haya , Zilbermann Israel , Meyerstein Dan
Published: September 2017

Recently it was reported that copper bicarbonate/carbonate complexes are good electro‐catalysts for water oxidation. However, the results did not enable a decision whether the active oxidant is a CuIII or a CuIV complex. Kinetic analysis of pulse radiolysis measurements coupled with DFT calculations point out that CuIII(CO3)n3−2n complexes are the active intermediates in the electrolysis of CuII(CO3)n2−2n solution. The results enable the evaluation of E°[(CuIII/II(CO3)n)aq]≈1.42 V versus NHE at pH 8.4. This redox potential is in accord with the electrochemical report. As opposed to literature suggestions for water oxidation, the present results rule out single‐electron transfer from CuIII(CO3)n3−2n to yield hydroxyl radicals. Significant charge transfer from the coordinated carbonate to CuIII results in the formation of C2O62− by means of a second‐order reaction of CuIII(CO3)n3−2n. The results point out that carbonate stabilizes transition‐metal cations at high oxidation states, not only as a good sigma donor, but also as a non‐innocent ligand.
C(sp3)−H Bond Activation by Vinylidene Gold(I) Complexes: A Concerted Asynchronous or Stepwise Process?
Authors: Klein Johannes E. M. N. , Knizia Gerald , Nunes dos Santos Comprido Laura , Kästner Johannes , Hashmi A. Stephen K.
Published: September 2017

A detailed analysis of the C(sp3)−H activation process by vinylidene AuI complexes is described based on an intrinsic bond orbital analysis. Based on our analysis this event can be divided into three phases: (i) hydride transfer, (ii) C−C bond formation, and (iii) σ to π rearrangement of the lone pair coordinated to Au. Small perturbations of the system lead to either a concerted asynchronous reaction, or a stepwise reaction featuring an intermediate with a C‐H‐C three‐centre two‐electron (3c–2e) bond. The role of π‐donating substituents is highlighted and provides a way of controlling reactions of this type in future experimental studies.
Construction of Condensed Polycyclic Aromatic Frameworks through Intramolecular Cycloaddition Reactions Involving Arynes Bearing an Internal Alkyne Moiety
Authors: Yoshida Suguru , Shimizu Keita , Uchida Keisuke , Hazama Yuki , Igawa Kazunobu , Tomooka Katsuhiko , Hosoya Takamitsu
Published: September 2017

Facile synthetic methods for condensed polycyclic aromatic compounds via aryne intermediates are reported. The generation of arynes bearing a (3‐arylpropargyl)oxy group from the corresponding o‐iodoaryl triflate‐type precursors efficiently afforded arene‐fused oxaacenaphthene derivatives, which were formed through intramolecular [2+4] cycloaddition. Extending the method to the generation of arynes bearing a 1,3‐diyne moiety led to a continuous generation of naphthalyne intermediate through the hexadehydro Diels–Alder reaction involving the aryne triple bond. This novel type of aryne‐relay chemistry enabled the synthesis of a unique aminoarylated oxaacenaphthene derivative and highly ring‐fused anthracene derivatives.
Total Synthesis of the Diglycosidic Tetramic Acid Ancorinoside A
Authors: Petermichl Markus , Schobert Rainer
Published: September 2017

Ancorinoside A, a metabolite of a sponge Ancorina sp., was prepared in 18 steps as the first derivative of this class of glycosylated 3‐acyltetramic acids. It features a β‐d‐glucopyranosyl‐(1→4)‐β‐d‐galacturonic acid linked to a d‐aspartic acid derived tetramic acid via a 3‐docosanoyl spacer. The diglycoside was built up by connecting the protected monosaccharides d‐galactose and d‐glucose via a thioglycoside glycosylation. Attachment of the spacer by a subsequent Schmidt glycosylation of this diglycoside, TEMPO oxidation to the uronic acid, functionalisation of the spacer terminus with an N‐(β‐ketoacyl)aspartate, and a final Dieckmann cyclisation were the key steps leading to ancorinoside A. This approach should also allow access to ancorinoside D.
An ultrasound‐conductivity method for measuring gas holdup in a microbubble‐based gas‐liquid system
Authors: Weng Liangyu , Zhang Jinzhao , Zhang Wen‐Hui
Published: September 2017

Due to the high specific surface area of microbubble‐based systems, the concept of gas‐liquid separation has successful applications in many fields, such as oil‐water separation, algal harvesting, micro‐extraction, membrane pretreatment, and water treatment. Gas holdup is an important parameter in such systems. However, the conventional measurement methods for the macrobubble system may not be directly applicable to the microbubble system due to small bubble size and low gas holdup. In this study, an ultrasound‐conductivity method under non‐isokinetic sampling conditions was developed to measure gas holdup in the microbubble‐based gas‐liquid system. The measurement setup consists of a sampling probe, a bubble coalescence unit, and a conductivity measurement unit. A key feature of the setup is a bubble coalescence unit to convert microbubbles to macrobubbles for conductivity measurement. The results showed that the bubble coalescence unit, made of an ultrasonic bath and a bubble‐coalescence cell, was successful in forming macrobubbles so that accurate conductivity measurements could be made. Under non‐isokinetic sampling conditions, the relationship between the extraction parameter (the gas volume fraction in the sampling probe) and the true gas holdup was established in flotation columns. The results indicate that the relationship does not depend on other factors, such as sampling probe orientation and flotation column diameter. Therefore, the developed ultrasound‐conductivity method has great potential in microbubble‐based gas‐liquid system.
Recent Developments in Azide‐Free Synthesis of 1,2,3‐Triazoles
Authors: Chen Zhengkai , Cao Gangjian , Song Jinyu , Ren Hongjun
Published: September 2017

1,2,3‐Triazoles, as one of the most significant nitrogen‐containing heterocycles due to their extensive use in biology, material science and organic synthesis, have aroused great interest. 1,2,3‐Triazoles are commonly synthesized by metal‐catalyzed azide–alkyne cycloaddition and organocatalytic azide–carbonyl cycloaddition, which indispensably employ the toxic and potentially explosive azides. The azide‐free synthetic approaches provide a powerful and straightforward alternative to the assembly of diverse 1,2,3‐triazoles without the use of azides. In this review, we summarize the recent development of the construction of 1,2,3‐triazoles under azide‐free conditions.
High‐resolution imaging of muscle attachment structures in Caenorhabditis elegans
Authors: Qadota Hiroshi , Matsunaga Yohei , Nguyen Ken C.Q. , Mattheyses Alexa , Hall David H. , Benian Guy M.
Published: September 2017

We used structured illumination microscopy (SIM) to obtain super‐resolution images of muscle attachment structures in Caenorhabditis elegans striated muscle. SIM imaging of M‐line components revealed two patterns: PAT‐3 (β‐integrin) and proteins that interact in a complex with the cytoplasmic tail of β‐integrin and localize to the basal muscle cell membrane [UNC‐112 (kindlin), PAT‐4 (ILK), UNC‐97 (PINCH), PAT‐6 (α‐parvin), and UNC‐95], are found in discrete, angled segments with gaps. In contrast, proteins localized throughout the depth of the M‐line (UNC‐89 (obscurin) and UNC‐98) are imaged as continuous lines. Systematic immunostaining of muscle cell boundaries revealed that dense body components close to the basal muscle cell membrane also localize at cell boundaries. SIM imaging of muscle cell boundaries reveal “zipper‐like” structures. Electron micrographs reveal electron dense material similar in appearance to dense bodies located adjacent to the basolateral cell membranes of adjacent muscle cells separated by ECM. Moreover, by EM, there are a variety of features of the muscle cell boundaries that help explain the zipper‐like pattern of muscle protein localization observed by SIM. Short dense bodies in atn‐1 mutants that are null for α‐actinin and lack the deeper extensions of dense bodies, showed “zipper‐like” structures by SIM similar to cell boundary structures, further indicating that the surface‐proximal components of dense bodies form the “zipper‐like” structures at cell boundaries. Moreover, mutants in thin and thick filament components do not have “dot‐like” dense bodies, suggesting that myofilament tension is required for assembly or maintenance of proper dense body shape.
Functional N‐Formyl Peptide Receptor 2 (FPR2) Antagonists Based on the Ureidopropanamide Scaffold Have Potential To Protect Against Inflammation‐Associated Oxidative Stress
Authors: Stama Madia L. , Lacivita Enza , Kirpotina Liliya N. , Niso Mauro , Perrone Roberto , Schepetkin Igor A. , Quinn Mark T. , Leopoldo Marcello
Published: September 2017

Formyl peptide receptor 2 (FPR2) is a G protein coupled receptor belonging to the N‐formyl peptide receptor (FPR) family that plays critical roles in peripheral and brain inflammatory responses. FPR2 has been proposed as a target for the development of drugs that could facilitate the resolution of chronic inflammatory reactions by enhancing endogenous anti‐inflammation systems. Starting from lead compounds previously identified in our laboratories, we designed a new series of ureidopropanamide derivatives with the goal of converting functional activity from agonism into antagonism and to develop new FPR2 antagonists. Although none of the compounds behaved as antagonists, some of the compounds were able to induce receptor desensitization and, thus, functionally behaved as antagonists. Evaluation of these compounds in an in vitro model of neuroinflammation showed that they decreased the production of reactive oxygen species in mouse microglial N9 cells after stimulation with lipopolysaccharide. These FPR2 ligands may protect cells from damage due to inflammation‐associated oxidative stress.
Tangential migration of corridor guidepost neurons contributes to anxiety circuits
Authors: Tinterri Andrea , Deck Marie , Keita Maryama , Mailhes Caroline , Rubin Anna Noren , Kessaris Nicoletta , Lokmane Ludmilla , Bielle Franck , Garel Sonia
Published: September 2017

In mammals, thalamic axons are guided internally toward their neocortical target by corridor (Co) neurons that act as axonal guideposts. The existence of Co‐like neurons in non‐mammalian species, in which thalamic axons do not grow internally, raised the possibility that Co cells might have an ancestral role. Here, we investigated the contribution of corridor (Co) cells to mature brain circuits using a combination of genetic fate‐mapping and assays in mice. We unexpectedly found that Co neurons contribute to striatal‐like projection neurons in the central extended amygdala. In particular, Co‐like neurons participate in specific nuclei of the bed nucleus of the stria terminalis, which plays essential roles in anxiety circuits. Our study shows that Co neurons possess an evolutionary conserved role in anxiety circuits independently from an acquired guidepost function. It furthermore highlights that neurons can have multiple sequential functions during brain wiring and supports a general role of tangential migration in the building of subpallial circuits.
Interconversion Rates between Conformational States as Rationale for the Membrane Permeability of Cyclosporines
Authors: Witek Jagna , Mühlbauer Max , Keller Bettina G. , Blatter Markus , Meissner Axel , Wagner Trixie , Riniker Sereina
Published: September 2017

Cyclic peptides have regained interest as potential inhibitors of challenging targets but have often a low bioavailability. The natural product cyclosporine A (CsA) is the textbook exception. Despite its size and polar backbone, it is able to passively cross membranes. This ability is hypothesized to be due to a conformational change from the low‐energy conformation in water to a “congruent” conformation that is populated both in water and inside the membrane. Here, we use a combination of NMR measurements and kinetic models based on molecular dynamics simulations to rationalize the difference in the membrane permeability of cyclosporine E (CsE) and CsA. The structure of CsE differs only in a backbone methylation, but its membrane permeability is one order of magnitude lower. The most striking difference is found in the interconversion rates between the conformational states favored in water and in chloroform, which are up to one order of magnitude slower for CsE compared to CsA.
Probing RNA Folding Pathways by RNA Fingerprinting
Authors: Woodson Sarah A.
Published: September 2017

This unit provides protocols for using native polyacrylamide gel electrophoresis to distinguish folding and unfolding conformers of RNA. It is useful for studying conformers that can exchange in a period of minutes or seconds, and that are thus difficult to study by solution‐based methods. Conformers that have been separated and immobilized in the gel matrix can be used to study catalytic activity with or without being eluted from the gel. The method can be applied to a wide variety of catalytic RNAs and RNA‐protein complexes. © 2017 by John Wiley & Sons, Inc.
Natural and Artificial Mn4Ca Cluster for the Water Splitting Reaction
Authors: Chen Changhui , Li Yanxi , Zhao Guoqing , Yao Ruoqing , Zhang Chunxi
Published: September 2017

The oxygen‐evolving center (OEC) in photosystem II (PSII) is a unique biological catalyst that splits water into electrons, protons, and O2 by using solar energy. Recent crystallographic studies have revealed that the structure of the OEC is an asymmetric Mn4Ca cluster, which provides a blueprint to develop man‐made water‐splitting catalysts for artificial photosynthesis. Although it is a great challenge to mimic the whole structure and function of the OEC in the laboratory, significant advances have recently been achieved. In this Minireview, recent progress on mimicking the natural OEC is discussed. New strategies are suggested to construct more stable and efficient new generation of catalytic materials for the water splitting reaction based on the artificial Mn4Ca cluster in the future.
Strongly Coupled Molybdenum Carbide on Carbon Sheets as a Bifunctional Electrocatalyst for Overall Water Splitting
Authors: Wang Hao , Cao Yingjie , Sun Cheng , Zou Guifu , Huang Jianwen , Kuai Xiaoxiao , Zhao Jianqing , Gao Lijun
Published: September 2017

Invited for this month′s cover is the group of Prof. Lijun Gao in the Soochow Institute for Energy and Materials InnovationS (SIEMIS) at Soochow University. The image shows the overall water splitting catalyzed by a Mo2C‐based bifunctional electrocatalyst. The Full Paper itself is available at 10.1002/cssc.201701276.
Coenzyme Q10 Prevents the Interleukin‐1 Beta Induced Inflammatory Response via Inhibition of MAPK Signaling Pathways in Rat Articular Chondrocytes
Authors: Li Xing , Guo Yuanqing , Huang Shuai , He Minhui , Liu Qiaoli , Chen Weizhi , Liu Minghao , Xu Dongliang , He Peiheng
Published: September 2017

Preclinical Research

Osteoarthritis (OA) is a widely prevalent degenerative joint disease that severely impairs the health of the elderly population resulting in a heavy economic burden worldwide. Coenzyme Q10 (CoQ10) has shown anti‐inflammatory effects in some diseases. The present study aimed to investigate if CoQ10 would suppress catabolic responses of interleukin (IL)‐1β‐induced chondrocytes. Rat chondrocytes were cultured and pretreated with CoQ10, and then stimulated with or without IL‐1β (10 ng/ml). The expression and production of matrix metalloproteinase (MMP)‐3, MMP‐9, and MMP13 were determined using real‐time PCR and Western blotting. CoQ10 suppressed MMP‐3, MMP‐9, and MMP13 production induced by IL‐1β, and markedly inhibited IL‐1β‐induced MAPK pathways in rat chondrocytes. The present study provides insight into potential mechanisms by which CoQ10 protects against degeneration of cartilage in patients with OA, which may lead to new approaches for the treatment of OA.Drug Dev Res 78 : 403‐410, 2017. © 2017 Wiley Periodicals, Inc.
[HDL‐C/apoA‐I]: A multivessel cardiometabolic risk marker in women with T2DM
Authors: Hermans Michel P. , Valensi Paul , Ahn Sylvie A. , Rousseau Michel F.
Published: September 2017

Aims

Although women have higher high‐density lipoprotein cholesterol (HDL‐C) than have men, their HDL particles are also prone to become small, dense, and dysfunctional in case of type 2 diabetes mellitus (T2DM). To assess the vascular risk related to HDLs of different sizes/densities without direct measurement, we adjusted HDL‐C to its main apolipoprotein (apoA‐I) as [HDL‐C/apoA‐I]. This ratio estimates HDL sizes and provides indices as to their number, cholesterol load, and density.

Methods

We stratified 280 Caucasian T2DM women according to [HDL‐C/apoA‐I] quartiles (Q) to determine how they are segregated according to cardiometabolic risk, β‐cell function, glycaemic control, and vascular complications. Five parameters were derived from combined determination of HDL‐C and apoA‐I: HDL size, HDL number, cholesterol load per particle (pP), apoA‐I pP, and HDL density.

Results

An adverse cardiometabolic profile characterized QI and QII patients whose HDLs were denser and depleted in apoA‐I, whereas QIII patients had HDLs with characteristics closer to those of controls. QIV patients had HDLs of supernormal size/composition and a more favourable phenotype in terms of fat distribution; insulin sensitivity (64% vs 41%), metabolic syndrome, and β‐cell function (32% vs 23%); exogenous insulin (44 vs 89 U·d−1); and glycaemic control (glycated haemoglobin, 56 vs 61 mmol·mol−1), associated with lower prevalence of microvascular/macrovascular complications: all‐cause microangiopathy 47% vs 61%; retinopathy 22% vs 34%; all‐cause macroangiopathy 19% vs 31%; and coronary artery disease 6% vs 24% (P < .05).

Conclusion

[HDL‐C/apoA‐I] can stratify T2DM women according to metabolic phenotype, macrovascular and coronary damage, β‐cell function, microangiopathic risk, and retinopathy. This ratio is a versatile and readily available marker of cardiometabolic status and vascular complications in T2DM women.
Dwarfism in homozygous Agc1CreERT mice is associated with decreased expression of aggrecan
Authors: Rashid Harunur , Chen Haiyan , Hassan Quamarul , Javed Amjad
Published: September 2017

Aggrecan (Acan), a large proteoglycan is abundantly expressed in cartilage tissue. Disruption of Acan gene causes dwarfism and perinatal lethality of homozygous mice. Because of sustained expression of Acan in the growth plate and articular cartilage, AgcCre model has been developed for the regulated ablation of target gene in chondrocytes. In this model, the IRES‐CreERT‐Neo‐pgk transgene is knocked‐in the 3′UTR of the Acan gene. We consistently noticed variable weight and size among the AgcCre littermates, prompting us to examine the cause of this phenotype. Wild‐type, Cre‐heterozygous (Agc+/Cre), and Cre‐homozygous (AgcCre/Cre) littermates were indistinguishable at birth. However, by 1‐month, AgcCre/Cre mice showed a significant reduction in body weight (18–27%) and body length (19–22%). Low body weight and dwarfism was sustained through adulthood and occurred in both genders. Compared with wild‐type and Agc+/Cre littermates, long bones and vertebrae were shorter in AgcCre/Cre mice. Histological analysis of AgcCre/Cre mice revealed a significant reduction in the length of the growth plate and the thickness of articular cartilage. The amount of proteoglycan deposited in the cartilage of AgcCre/Cre mice was nearly half of the WT littermates. Analysis of gene expression indicates impaired differentiation of chondrocyte in hyaline cartilage of AgcCre/Cre mice. Notably, both Acan mRNA and protein was reduced by 50% in AgcCre/Cre mice. A strong correlation was noted between the level of Acan mRNA and the body length. Importantly, Agc+/Cre mice showed no overt skeletal phenotype. Thus to avoid misinterpretation of data, only the Agc+/Cre mice should be used for conditional deletion of a target gene in the cartilage tissue.
Long‐term agricultural management does not alter the evolution of a soybean–rhizobium mutualism
Authors: Schmidt Jennifer E. , Weese Dylan J. , Lau Jennifer A.
Published: September 2017

Leguminous crops, like soybeans, often rely on biologically fixed nitrogen via their symbiosis with rhizobia rather than synthetic nitrogen inputs. However, agricultural management practices may influence the effectiveness of biological nitrogen fixation (BNF). While the ecological effects of agricultural management on rhizobia have received some attention, the evolutionary effects have been neglected in comparison. Resource mutualism theory predicts that evolutionary effects are likely, however. Both fertilization and tillage are predicted to cause the evolution of rhizobia that provide fewer growth benefits to plant hosts and fix less nitrogen. This study capitalized on a Long‐Term Ecological Research experiment that manipulated agricultural management practices in a corn‐soybean‐wheat row crop system for 24 yr to investigate whether four different management practices (conventional, no‐till, low chemical input, and certified organic) cause rhizobia populations to evolve to become more or less cooperative. We found little evidence that 24 yr of varying management practices affect the net growth benefits rhizobia provide to soybeans, although soybean plants inoculated with soils collected from conventional treatments tended to have lower BNF rates than plants inoculated with soils from the no‐till, low input, and organic management treatments. These findings suggest that rhizobia will continue to provide adequate growth benefits to leguminous crops in the future, even in intensively managed systems.
Associations between eating disorder related symptoms and participants’ utilization of an individualized Internet‐based prevention and early intervention program
Authors: Kindermann Sally , Moessner Markus , Ozer Fikret , Bauer Stephanie
Published: September 2017

Objective

Flexible, individualized interventions allow participants to adjust the intensity of support to their current needs. Between‐persons, participants with greater needs can receive more intense support, within‐persons, participants can adjust utilization to their current level of symptoms. The purpose of the present study was to analyze associations between ED‐related symptoms and utilization of the individualized program ProYouth both between‐ and within‐persons, aiming to investigate whether participants adapt utilization intensity to their current needs.

Method

Generalized estimated equations (GEEs) were used to analyze log data on program utilization (monthly page visits, monthly use of chats and forum) assessed via server logs and self‐reported data on ED‐related symptoms from N = 394 ProYouth participants who provided longitudinal data for at least two months.

Results

Between‐persons, page visits per month were significantly associated with compensatory behavior, body dissatisfaction, and binge eating. Monthly use of the more intense modules with personal support chat and forum was associated with the frequency of compensatory behavior. Within‐persons, unbalanced nutrition and dieting showed the strongest associations with monthly page visits. Monthly use of chats and forum was significantly associated with compensatory behavior and unbalanced nutrition and dieting.

Discussion

Results indicate that program utilization is associated with ED‐related symptoms between‐ as well as within‐persons. The individualized, flexible approach of ProYouth thus seems to be a promising way for Internet‐based provision of combined prevention and early intervention programs addressing ED.
BAFF augments IgA2 and IL‐10 production by TLR7/8 stimulated total peripheral blood B cells
Authors: den Hartog Gerco , van Osch Thijs L.J. , Vos Martijn , Meijer Ben , Savelkoul Huub F.J. , van Neerven R.J. Joost , Brugman Sylvia
Published: September 2017

Class‐switching of B cells to IgA can be induced via both T‐cell‐dependent and T‐cell‐independent mechanisms. IgA is most predominantly produced mucosally and is important for combating infections and allergies. In contrast to mice, humans have two forms of IgA; IgA1 and IgA2 with diverse tissue distribution. In early life, IgA levels might be sub‐optimal especially during the fall season when bacterial and viral infections are more common. Therefore, we investigated using human B cells whether T‐cell‐independent factors ‐promoting cell survival, class switching and immunoglobulin secretion‐ BAFF, APRIL, IL‐10 and retinoic acid can boost IgA production in the context of viral or bacterial infection. To this end total and naive peripheral blood B cells were stimulated with these factors for 6 days in the presence or absence of TLR7/8 agonist R848 (mimicking viral infection) or TLR9 agonist CpG‐ODN (mimicking bacterial infection). We show that BAFF significantly augments IgA2 production in TLR7/8 stimulated mature, but not naïve B cells. In addition, BAFF augments IL‐10 production and viability in TLR7/8 and TLR9 stimulated mature B cells. These data warrant further investigation of its role in immune regulation both in the periphery and mucosal tissues in early life or during disease.
Sugar‐Incorporated N‐Heterocyclic‐Carbene‐Containing Gold(I) Complexes: Synthesis, Characterization, and Cytotoxic Evaluation
Authors: Cucciolito Maria E. , Trinchillo Marina , Iannitti Roberta , Palumbo Rosanna , Tesauro Diego , Tuzi Angela , Ruffo Francesco , D'Amora Angela
Published: September 2017

A series of neutral and cationic gold(I) complexes bearing a glucopyranoside‐incorporated N‐heterocyclic carbene (NHC) ligand are synthetized and structurally characterized. Different secondary ligands (chlorido, phosphane, or sugar–NHC) are employed to tune the properties of the complexes. The antiproliferative effects of the compounds are evaluated against PC‐3 prostate cancer cells and a panel of human tumor cell lines. The activities of the phosphane complexes are comparable to that observed for cisplatin. The combined results provide further insights into the biological behavior of NHC–gold complexes.
An Efficient Method for the Surface Functionalization of Luminescent Quantum Dots with Lipoic Acid Based Ligands
Authors: La Rosa Marcello , Avellini Tommaso , Lincheneau Christophe , Silvi Serena , Wright, Iain A. , Constable Edwin C. , Credi Alberto
Published: September 2017

We describe herein an operationally advantageous general methodology for efficiently activating lipoic acid based compounds, a family of popular surface ligands for semiconductor nanocrystals, through the use of a borohydride exchange resin, and the use of the activated species to replace the native surface ligands of quantum dots. The procedure enabled phase transfer of the nanocrystals between polar and aqueous media and, if unsubstituted lipoic acid was used, a facile adjustment of their solubility in a wide range of solvents with varying polarity (from hexane to water). We show that the protocol is applicable to different types of nanocrystals and a variety of lipoic acid based ligands, and that the resulting quantum dots maintain their optical properties, in particular, an intense luminescence, and long‐term colloidal stability.
Single‐Molecule Magnetic Behavior in a Calix[8]arene‐Capped Heterometallic {DyIII4CoII4} Square‐Antiprismatic Cluster
Authors: Han Haitao , Li Xiao‐Lei , Zhu Xiaofei , Zhang Guoshuai , Hang Xinxin , Tang Jinkui , Liao Wuping
Published: September 2017

Two isostructural octanuclear {(LnIII4CoII4)(C8A)2} compounds (Ln = Dy, Er; H8C8A = p‐tert‐butylcalix[8]arene) are synthesized under solvothermal conditions for magnetic study. For comparison, an yttrium compound, having a similar structure, except for some coordinated DEF molecules replaced by water molecules, is obtained. These three compounds are featured with a sandwich‐like motif in which the heterometallic {LnIII4Co4II} square‐antiprismatic cluster is sandwiched between two calix[8]arene molecules in double‐cone conformation. Magnetic measurements reveal that the {DyIII4CoII4} compound exhibits single‐molecule magnetic behavior.
Versatile Barium and Calcium Imidazolium‐Dicarboxylate Heterogeneous Catalysts in Quinoline Synthesis
Authors: Albert‐Soriano María , Trillo Paz , Soler Tatiana , Pastor Isidro M.
Published: September 2017

This article details the development of heterogeneous catalysts based on calcium and barium in combination with the organic linker 1,3‐bis(carboxymethyl)imidazolium (bcmim). The linker and the materials from alkaline earth metals are easily prepared under very smooth conditions. The use of linkers with different counterions (Cl or Br) provided different materials. Calcium‐ and barium‐based catalysts were successfully employed in the preparation of quinoline derivatives from ketones and 2‐aminoarylaldehydes or 2‐aminoarylketones. In general, barium‐based catalysts provided better results than calcium, although the latter are an excellent complement for certain substrates. Thus, a notable feature of such catalysts is the possibility of accessing a variety of complementary heterogeneous catalytic systems, rendering the catalysis adaptive to the reactant.||||||
Copper‐Catalyzed S‐Arylation of Tetraalkylthiuram Disulfides by Using Diaryliodonium Salts
Authors: Zeng Meng‐Tian , Xu Wan , Liu Xing , Chang Cai‐Zhu , Zhu Hui , Dong Zhi‐Bing
Published: September 2017

An efficient and convenient procedure for the S‐arylation of tetraalkylthiuram disulfides by using diaryliodonium salts was explored. In the presence of CuI/KOtBu, two kinds of S‐aryl dithiocarbamates could be obtained in good to excellent yields at one time with no clear selectivity. This method has the advantages of efficiency, good atom economy, and broad substrate scope. This protocol allows the facile and convenient preparation of some potentially biologically active compounds.
The two‐sided nature of individual and intragroup experiences in the aftermath of collective victimization: Findings from four diaspora groups
Authors: Vollhardt Johanna Ray , Nair Rashmi
Published: September 2017

Most social psychological research on collective victimhood has examined its consequences for intergroup relations. Less attention has been paid to individual and intragroup processes associated with collective victimization, which the present study aimed to examine. We conducted eight focus group interviews among four diaspora communities (Armenian Americans, Burundian refugees, Jewish Americans, Nepali‐speaking Bhutanese refugees) with historical or more recent experiences of collective victimization. Thematic analysis revealed three major foci shared across communities (but with different emphases within each focus), which included juxtaposed themes that highlight the two‐sided nature of experiencing and coping with collective victimization and its aftermath: Vulnerability and struggle versus resilience and strength, loss versus continuity and renewal, and silence about versus transmission of knowledge about ingroup victimization. These findings illustrate how groups integrate seemingly opposite poles of collective victimization that characterize this complex and multifaceted experience, which has important theoretical implications.
Tissue‐specific and time‐dependent clonal expansion of ENU‐induced mutant cells in gpt delta mice
Authors: Nakayama Takafumi , Sawai Tomoko , Masuda Ikuko , Kaneko Shinya , Yamauchi Kazumi , Blyth Benjamin J. , Shimada Yoshiya , Tachibana Akira , Kakinuma Shizuko
Published: September 2017

DNA mutations play a crucial role in the origins of cancer, and the clonal expansion of mutant cells is one of the fundamental steps in multistage carcinogenesis. In this study, we correlated tumor incidence in B6C3F1 mice during the period after exposure to N‐ethyl‐N‐nitrosourea (ENU) with the persistence of ENU‐induced mutant clones in transgenic gpt delta B6C3F1 mice. The induced gpt mutations afforded no selective advantage in the mouse cells and could be distinguished by a mutational spectrum that is characteristic of ENU treatment. The gpt mutations were passengers of the mutant cell of origin and its daughter cells and thus could be used as neutral markers of clones that arose and persisted in the tissues. Female B6C3F1 mice exposed for 1 month to 200 ppm ENU in the drinking water developed early thymic lymphomas and late liver and lung tumors. To assay gpt mutations, we sampled the thymus, liver, lung, and small intestine of female gpt delta mice at 3 days, 4 weeks, and 8 weeks after the end of ENU exposure. Our results reveal that, in all four tissues, the ENU‐induced gpt mutations persisted for weeks after the end of mutagen exposure. Clonal expansion of mutant cells was observed in the thymus and small intestine, with the thymus showing larger clone sizes. These results indicate that the clearance of mutant cells and the potential for clonal expansion during normal tissue growth depends on tissue type and that these factors may affect the sensitivity of different tissues to carcinogenesis. Environ. Mol. Mutagen. 58:592–606, 2017. © 2017 Wiley Periodicals, Inc.
Does the permeability of gravel river beds affect near‐bed hydrodynamics?
Authors: Cooper James R. , Ockleford Annie , Rice Stephen P. , Powell D. Mark
Published: September 2017

The permeability of river beds is an important control on hyporheic flow and the movement of fine sediment and solutes into and out of the bed. However, relatively little is known about the effect of bed permeability on overlying near‐bed flow dynamics, and thus on fluid advection at the sediment–water interface. This study provides the first quantification of this effect for water‐worked gravel beds. Laboratory experiments in a recirculating flume revealed that flows over permeable beds exhibit fundamental differences compared with flows over impermeable beds of the same topography. The turbulence over permeable beds is less intense, more organised and more efficient at momentum transfer because eddies are more coherent. Furthermore, turbulent kinetic energy is lower, meaning that less energy is extracted from the mean flow by this turbulence. Consequently, the double‐averaged velocity is higher and the bulk flow resistance is lower over permeable beds, and there is a difference in how momentum is conveyed from the overlying flow to the bed surface. The main implications of these results are three‐fold. First, local pressure gradients, and therefore rates of material transport, across the sediment–water interface are likely to differ between impermeable and permeable beds. Second, near‐bed and hyporheic flows are unlikely to be adequately predicted by numerical models that represent the bed as an impermeable boundary. Third, more sophisticated flow resistance models are required for coarse‐grained rivers that consider not only the bed surface but also the underlying permeable structure. Overall, our results suggest that the effects of bed permeability have critical implications for hyporheic exchange, fluvial sediment dynamics and benthic habitat availability. © 2017 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd.
Protease activated receptor 2 controls myelin development, resiliency and repair
Authors: Yoon Hyesook , Radulovic Maja , Walters Grant , Paulsen Alex R. , Drucker Kristen , Starski Phillip , Wu Jianmin , Fairlie David P. , Scarisbrick Isobel A.
Published: September 2017

Oligodendrocytes are essential regulators of axonal energy homeostasis and electrical conduction and emerging target cells for restoration of neurological function. Here we investigate the role of protease activated receptor 2 (PAR2), a unique protease activated G protein‐coupled receptor, in myelin development and repair using the spinal cord as a model. Results demonstrate that genetic deletion of PAR2 accelerates myelin production, including higher proteolipid protein (PLP) levels in the spinal cord at birth and higher levels of myelin basic protein and thickened myelin sheaths in adulthood. Enhancements in spinal cord myelin with PAR2 loss‐of‐function were accompanied by increased numbers of Olig2‐ and CC1‐positive oligodendrocytes, as well as in levels of cyclic adenosine monophosphate (cAMP), and extracellular signal related kinase 1/2 (ERK1/2) signaling. Parallel promyelinating effects were observed after blocking PAR2 expression in purified oligodendrocyte cultures, whereas inhibiting adenylate cyclase reversed these effects. Conversely, PAR2 activation reduced PLP expression and this effect was prevented by brain derived neurotrophic factor (BDNF), a promyelinating growth factor that signals through cAMP. PAR2 knockout mice also showed improved myelin resiliency after traumatic spinal cord injury and an accelerated pattern of myelin regeneration after focal demyelination. These findings suggest that PAR2 is an important controller of myelin production and regeneration, both in the developing and adult spinal cord.
Association of gout and depression: A systematic review and meta‐analysis
Authors: Lin Song , Zhang Huaqi , Ma Aiguo
Published: September 2017

Objective

Several studies have shown that gout is associated with depression symptoms. In this study, a systematic review and meta‐analysis was performed to explore the relationship between gout and depression.

Methods

Published articles were identified through a comprehensive review of PUBMED and EMBASE. Data from studies reporting relative risks, odds ratios, or hazard ratios comparing the risk of depression among participants who had gout versus those without gout were analyzed. A random‐effect model was used to calculate pooled odds ratios and 95% confident intervals (CI).

Results

Seven studies, which included 411 745 participants, aligned with our inclusion criteria and were included in the meta‐analysis. Pooled analysis showed an association between gout and depression, with an odds ratio of 1.19 (95%CI, 1.11, 1.29; I2 = 60.2%). Subgroup‐analysis adjusted (or not) by study type or study quality showed a statistically significant association of gout and depression in all subgroups. Sensitivity analysis by 1‐study removed analysis, excluding articles of self‐reported gout assessment or male‐only, confirmed the robustness of our results.

Conclusion

Our meta‐analysis demonstrates a positive association between gout and depression. Further large‐scale prospective cohort studies are needed to investigate the causality between gout and depression.
“Discrete peaks” of excitability and map overlap reveal task‐specific organization of primary motor cortex for control of human forearm muscles
Authors: Massé‐Alarie Hugo , Bergin Michael J.G. , Schneider Cyril , Schabrun Siobhan , Hodges Paul W.
Published: September 2017

The primary motor cortex (M1) presents a somatotopic organization of body parts, but with overlap between muscle/movement representations. This distinct but overlapping M1 organization is believed to be important for individuated control and movement coordination, respectively. Discrete peaks of greater excitability observed within M1 might underpin organization of cortical motor control. This study aimed to examine interactions between M1 representations of synergist and antagonist forearm muscles, compare regions of greater excitability during different functional tasks, and compare characteristics of M1 representation recorded using surface and fine‐wire (fw) electrodes. Transcranial magnetic stimulation (TMS) was applied over M1 for mapping the representation of 4 forearm muscles (extensor carpi radialis brevis [ECRB], extensor digitorum communis, flexor carpi radialis, and flexor digitorum superficialis) during three tasks: rest, grip, and wrist extension in 14 participants. There are three main findings. First, discrete areas of peak excitability within the M1 representation of ECRBfw were identified during grip and wrist extension suggesting that different M1 areas are involved in different motor functions. Second, M1 representations of synergist muscles presented with greater overlap of M1 representations than muscles with mainly antagonist actions, which suggests a role in muscle coordination. Third, as larger normalized map volume and overlap were observed using surface than fine‐wire electrodes, data suggest that cross‐talk from adjacent muscles compromised interpretation of recordings made with surface electrodes in response to TMS. These results provide a novel understanding of the spatial organization of M1 with evidence of “functional somatotopy.” This has important implications for cortical control of movement. Hum Brain Mapp 38:6118–6132, 2017. © 2017 Wiley Periodicals, Inc.
5‐HTTLPR moderates the association between interdependence and brain responses to mortality threats
Authors: Luo Siyang , Yu Dian , Han Shihui
Published: September 2017

While behavioral research suggests an association between cultural worldview and decreased anxiety of death, the underlying neurobiological mechanisms remain unclear. Using functional MRI, we investigated whether and how the serotonin transporter promoter polymorphism (5‐HTTLPR), which has been associated with mental disorders such as anxiety and depression, moderates the associations between a cultural trait (i.e., interdependence) and self‐report of death anxiety/depression and between interdependence and brain responses to mortality threats. Long/long and short/short allele carriers of the 5‐HTTLPR were scanned using fMRI while they performed a one‐back task on death‐related, death‐unrelated negative, and neutral words. Participants’ interdependence and death anxiety/depression were assessed using questionnaires after scanning. We found that participants who assessed themselves with greater interdependence reported lower death anxiety/depression and showed decreased neural response to death‐related words in emotion‐related brain regions including the anterior cingulate, putamen, and thalamus. However, these results were evident in long/long allele carriers of the 5‐HTTLPR but not in short/short allele carriers who even showed positive associations between interdependence and neural activities in the anterior cingulate, putamen and thalamus in response to death‐related words. Our findings suggest candidate mechanisms for explaining the complex relationship between genotype, cultural traits, and mental/neural responses to mortality threats. Hum Brain Mapp 38:6157–6171, 2017. © 2017 Wiley Periodicals, Inc.