bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanistic Study of the Solvent‐Dependent Formation of Extended and Stacked Supramolecular Polymers Composed of Bis(imidazolylporphyrinatozinc) Molecules
Authors: Satake Akiharu , Suzuki Yuki , Sugimoto Motonobu , Kuramochi Yusuke 
Published: October 2019

AbstractBis(imidazolylporphyrinatozinc) molecules linked through a 1,3‐butadiynylene moiety respond to the solvents they are dissolved in to afford exclusively extended (E) or stacked (S) supramolecular polymers. This system is expected to be a solvation/desolvation indicator. However, the principles underlying the solvent‐dependent formation of the two types of polymers and the mechanism of the transformation between them are unclear. The formation of the polymers is considered to depend on the two types of complementary coordination bonds that can be formed and the π–π interactions between the porphyrins. In this study, the contributions and solvent dependence of both the coordination bonds and the π–π interactions have been investigated. The results clearly indicate that the coordination bonds are weakly or little solvent‐dependent, and that the π–π interactions function effectively only in the inner porphyrins of the S‐polymer and are strongly solvent‐dependent. Thermodynamic analysis revealed that the formation of the E‐ or S‐polymer in solution is determined by the total energies and the type of solvent used. The transformation of the E‐ to S‐polymer was investigated by gel permeation chromatography. The kinetics of the transformation were also determined. The role of the terminal imidazolylporphyrinatozinc moieties was also investigated: The results indicate that the transformation from the E‐ to S‐polymer occurs by an exchange mechanism between the polymers, induced by attack of terminal free imidazolyl groups on a polymer to zinc porphyrins on other polymers.
A Photoactivatable Small‐Molecule Probe for the In Vivo Capture of Polyketide Intermediates
Authors: Kilgour Samantha L. , Jenkins Robert , Tosin Manuela 
Published: October 2019

AbstractA photolabile carba(dethia) malonyl N‐acetylcysteamine derivative was devised and prepared for the trapping of biosynthetic polyketide intermediates following light activation. From the lasalocid A polyketide assembly in a mutant strain of the soil bacterium Streptomyces lasaliensis, a previously undetected cyclised intermediate was identified and characterised, providing a new outlook on the timing of substrate processing.
A General Strategy for Through‐Bond Energy Transfer Fluorescence Probes Combining Intramolecular Charge Transfer: A Silyl Ether System for Endogenous Peroxynitrite Sensing
Authors: Lu Gonghao , Guo Yuxin , Zhuo Jiezhen , Li Xue , Chi Haijun , Zhang Zhiqiang 
Published: October 2019

AbstractA general strategy is reported for developing through‐bond energy transfer (TBET) fluorescence probes by combining intramolecular charge transfer (ICT). The strategy uses a coplanar donor‐π‐bridge‐acceptor system (SiOPh‐PyOH) without spirolactam. The off‐on switch of TBET and ICT is controlled by coplanar structure changes in the sensing process instead of spirolactam ring‐opening in traditional TBET probes. DFT calculations showed that the energy and charge transfers from SiOPh to PyOH are prohibited. Since the SiOPh has no fluorescence, the probe SiOPh‐PyOH shows fluorescence properties similar to that of pyrene. After sensing ONOO−, the silyl ether is removed and the probe changes into −OPh‐PyO−. Electron‐donating ICT from −OPh to PyO− induces a large redshift of emission to 594 nm (179 nm shift). TBET from −OPh to PyO− ensures the probe exhibits a large pseudo‐Stokes shift of 213 nm. Furthermore, the probe was successfully used in endogenous ONOO− detection. This study offers a new strategy for the construction of TBET probes emitting in the red region without spirolactam ring‐opening, a new ONOO− sensing system using silyl ether as a reaction site, and a method for the deprotection of silyl ethers with ONOOH under mild conditions.
Lead(II) Siloxides
Authors: Someşan Adrian‐Alexandru , Le Coz Erwann , Raţ Ciprian Ionuţ , Dorcet Vincent , Roisnel Thierry , Silvestru Cristian , Sarazin Yann 
Published: October 2019

AbstractAlthough PbII‐siloxides have been known until now to decompose to oxoclusters, here [{ROF}PbOSi(SiMe3)3] (ROF=fluoroalkoxide) and, most importantly, [Pb2{OSi(SiMe3)3}{μ2‐OSi(SiMe3)3}3], are presented. The unusual bonding pattern in the latter thermally stable dinuclear complex was investigated by crystallographic and computational methods. Its stability is much higher than that of the simple, yet elusive “[Pb(OSiPh3)2]”, for which decomposition pathways towards [Pb4(μ4‐O)(μ2‐OSiPh3)6] have been clearly established.
Fine Bubble‐based CO2 Capture Mediated by Triethanolamine Coupled to Whole Cell Biotransformation
Authors: Ohde Daniel , Thomas Benjamin , Matthes Simon , Percin Zeynep , Engelmann Claudia , Bubenheim Paul , Terasaka Koichi , Schlüter Michael , Liese Andreas 
Published: October 2019

AbstractCarbon capture technology can be set up in combination with biocatalysis to utilize the bound CO2 as substrate in the Kolbe‐Schmitt like enzymatic reaction. The exemplary whole cell biotransformation of catechol to 2,3‐dihydroxybenzoic acid in a triethanolamine‐mediated multiphase system shows increased equilibrium conversion. Apart from the beneficial thermodynamics, the inherent fluid properties of triethanolamine is enabling easy application of CO2 fine bubbles as highly efficient gassing method to minimize the CO2 demand and CO2 emissions.
Rationalising Supramolecular Hydrogelation of Bis‐Urea‐Based Gelators through a Multiscale Approach
Authors: Van Lommel Ruben , Rutgeerts Laurens A. J. , De Borggraeve Wim M. , De Proft Frank , Alonso Mercedes 
Published: October 2019

AbstractThe current approach to designing low‐molecular‐weight gelators relies on a laborious trial‐and‐error process, mainly because of the lack of an accurate description of the noncovalent interactions crucial for supramolecular gelation. In this work, we report a multiscale bottom‐up approach composed of several computational techniques to unravel the key interactions in a library of synthesized bis‐urea‐based gelators and rationalize their experimentally observed hydrogelation performance. In addition to density functional theory calculations and molecular dynamics, the noncovalent interaction index is applied as a tool to visualise and identify the different types of noncovalent interactions. Interestingly, as well as hydrogen bonds between urea moieties, hydrogen bonds between a urea moiety and a pyridine ring were shown to play a detrimental role in the early aggregation phase. These findings enabled us to explain the hydrogelation performance observed in a library of twelve bis‐urea derivatives, which were synthesized with 58–95 % yields. From this library, three compounds were discovered to effectively gel water, with the most efficient hydrogelator only requiring a concentration of 0.2 w/v%.
Optimizing Tissue Preservation for High‐Resolution Confocal Imaging of Single‐Molecule RNA‐FISH
Authors: Redmayne Nash , Chavez Shawn L. 
Published: October 2019

AbstractOver the past century, formalin‐fixed, paraffin‐embedded (FFPE) tissue samples have represented the standard for basic histology and immunostaining. However, FFPE has several limitations and less stringent tissue preservation methods are required for the visualization of nucleic acids at high resolution, particularly those that are expressed at low levels. Here, we describe the FFPE properties that negatively impact RNA integrity, an alternative tissue preservation technique that prevents RNA loss, and the steps necessary to optimize slide preparation for single‐molecule RNA fluorescent in situ hybridization (smRNA‐FISH) and imaging by confocal microscopy. This strategy retains RNA quality and eliminates formalin‐induced artifacts, thereby producing high‐resolution, diffraction‐limited confocal images of even rare RNA transcripts in tissues. As non‐coding RNAs and alternative splicing of gene isoforms continue to emerge as important regulators of human health and disease, a reliable, cost‐effective approach is required to examine the expression and localization of RNA targets in patient samples. © 2019 by John Wiley & Sons, Inc.Basic Protocol 1: Preparing an RNase‐free workstationSupport Protocol 1: Diethyl pyrocarbonate water treatmentSupport Protocol 2: Removing RNase contamination from glasswareBasic Protocol 2: BE70 tissue fixation and processingBasic Protocol 3: Cutting slide sections from paraffin blocksBasic Protocol 4: Specimen pre‐treatmentBasic Protocol 5: RNA fluorescent in situ hybridization labelingBasic Protocol 6: Slide mountingBasic Protocol 7: Generating deconvolution‐capable confocal micrographs
Factors influencing plasticity in the arrival‐breeding interval in a migratory species reacting to climate change
Authors: Low Matthew , Arlt Debora , Knape Jonas , Pärt Tomas , Öberg Meit 
Published: October 2019

AbstractClimate change is profoundly affecting the phenology of many species. In migratory birds, there is evidence for advances in their arrival time at the breeding ground and their timing of breeding, yet empirical studies examining the interdependence between arrival and breeding time are lacking. Hence, evidence is scarce regarding how breeding time may be adjusted via the arrival‐breeding interval to help local populations adapt to local conditions or climate change. We used long‐term data from an intensively monitored population of the northern wheatear (Oenanthe oenanthe) to examine the factors related to the length of 734 separate arrival‐to‐breeding events from 549 individual females. From 1993 to 2017, the mean arrival and egg‐laying dates advanced by approximately the same amount (~5–6 days), with considerable between‐individual variation in the arrival‐breeding interval. The arrival‐breeding interval was shorter for: (a) individuals that arrived later in the season compared to early‐arriving birds, (b) for experienced females compared to first‐year breeders, (c) as spring progressed, and (d) in later years compared to earlier ones. The influence of these factors was much larger for birds arriving earlier in the season compared to later arriving birds, with most effects on variation in the arrival‐breeding interval being absent in late‐arriving birds. Thus, in this population it appears that the timing of breeding is not constrained by arrival for early‐ to midarriving birds, but instead is dependent on local conditions after arrival. For late‐arriving birds, however, the timing of breeding appears to be influenced by arrival constraints. Hence, impacts of climate change on arrival dates and local conditions are expected to vary for different parts of the population, with potential negative impacts associated with these factors likely to differ for early‐ versus late‐arriving birds.
Gas film heat transfer as enhancement strategy for phase change materials
Authors: Arias Francisco J. , De Las Heras Salvador 
Published: October 2019

AbstractIn this work, consideration is given to an alternative strategy for phase change materials (PCMs) heat transfer enhancement with particular reference to horizontal plates. In contrast with current approaches in which heat transfer enhancement is pursued either by adapted geometries or acting on the thermal conductivity coefficient of a given PCM, here the problem is tackled by preventing the formation and contact of the front of solidification at the wall of the vessel by the deliberate presence of a gas film between the wall and the PCM. Because the presence of such a film, the front of solidification only can attains a certain critical thickness before gravitationally sinks by its own weight and then eliminating the continuous growth of the solid layer with the consequent reduction of conductive heat transfer and power output of the system as the solidification takes place which translates into an enhanced and steady power during the entire solidification process. It is shown that because the critical thickness of the solidified layer before sinks is a few millimeters or less and then smaller than practical gas films, therefore the heat transfer is controlled by the thickness and the thermal conductivity of the film. Additional R&D is required in order to arrive at a reliable practical and safe design.
Association between increased theta cordance and early response to ECT in late‐life depression
Authors: Ward Michael J. , Karim Helmet T. , Jessen Zachary F. , Ghuman Avniel Singh , Richardson R. Mark , Reynolds Charles F. , Karp Jordan F. 
Published: October 2019

ObjectivesMore than half of patients with major depression who do not respond to initial antidepressants become treatment resistant (TRD), and while electroconvulsive therapy (ECT) is effective, it involves anesthesia and other medical risks that are of concern in geriatric patients. Past studies have suggested that theta cordance (TC), a correlate of cerebral metabolism measured by electroencephalography, could guide treatment decisions related to patient selection and engagement of the therapeutic target.Methods/DesignEight patients with late‐life treatment resistant depression (LL‐TRD) underwent magnetoencephalography (MEG) at baseline and following seven sessions of ECT. We tested whether the mean and regional frontal cortex TC were able to differentiate early responders from nonresponders.ResultsFive patients whose depression severity decreased by >30% after seven sessions were considered early responders. We found no baseline differences in mean frontal TC between early responders compared with nonresponders, but early responders exhibited a significant increase in TC following ECT. Further, we found that compared with nonresponders, early responders exhibited a greater change in TC specifically within the right prefrontal cortex.ConclusionsThese results support the hypothesis that increases in frontal TC are associated with antidepressant response. We expand on previous findings by showing that this change is specific to the right prefrontal cortex. Validation of this neural marker could contribute to improved ECT outcomes, by informing early clinical decisions about the acute efficacy of this treatment.
Dose volume effects of re‐irradiation for locally recurrent nasopharyngeal carcinoma
Authors: Ng Wai‐Tong , Lee Michael CH , Fung Nelson TC , Wong Edwin CY , Cheung Alice KW , Chow James CH , Au Kwok‐Hung , Poon Darren MC , Lai Jessica WY , Chiang Chi‐Leung , Choi Horace CW , Chau Tin‐Ching , Lee Victor HF , Lee Anne WM 
Published: October 2019

AbstractBackgroundThis study analyzed the dose volume effects of re‐irradiation for locally recurrent nasopharyngeal carcinoma (NPC) and attempts to determine the optimal dose for the best survival.MethodsNinety‐one patients were studied. The local control, fatal complication, and overall survival were analyzed against the dose (in Equivalent Dose at 2 Gy/fractions) and recurrent gross tumor volume (GTV).ResultsThe local control and fatal complication rate appear to increase with prescribed dose. The overall survival peaks at around 60 Gy10. Local control decreases significantly with increasing GTV (P < .001) while overall survival shows similar trend (P = .06). No correlation was observed between the fatal complication rate and GTV volume. The dose response of local control appears to be stronger for smaller tumors.ConclusionGTV volume plays a significant role in local control. A 60 Gy10 appears to be optimal for the best survival outcome; higher doses might be considered for small tumors.
Fabrication of electrospun poly(lactic acid) nanoporous membrane loaded with niobium pentoxide nanoparticles as a potential scaffold for biomaterial applications
Authors: Marins Natália H. , Silva Ricardo M. , Ferrua Camila P. , Łukowiec Dariusz , Barbosa Ananda M. , Ribeiro Juliana S. , Nedel Fernanda , Zavareze Elessandra R. , Tański Tomasz , Carreño Neftalí L. V. 
Published: October 2019

AbstractTissue engineering aims to regenerate and restore damaged human organs and tissues using scaffolds that can mimic the native tissues. The requirement for modern and efficient biomaterials that are capable of accelerating the healing process has been considerably increased. In this work, a novel electrospun poly(lactic acid) (PLA) nanoporous membrane incorporated with niobium pentoxide nanoparticles (Nb2O5) for biomaterial applications was developed. Nb2O5 nanoparticles were obtained by microwave‐assisted hydrothermal synthesis, and different concentrations (0, 1, 3, and 5% wt/wt) were tested. Chemical, morphological, mechanical, and biological properties of membranes were evaluated. Cell viability results demonstrated that the membranes presented nontoxic effects. The incorporation of Nb2O5 improved cell proliferation without impairing the wettability, porosity, and mechanical properties of membranes. Membranes containing Nb2O5 nanoparticles presented biocompatible properties with suitable porosity, which facilitated cell attachment and proliferation while allowing diffusion of oxygen and nutrients. This study has demonstrated that Nb2O5 nanoparticle‐loaded electrospun PLA nanoporous membranes are potential candidates for drug delivery and wound dressing applications.
Kidney Disease Progression Does Not Decrease Intestinal Phosphorus Absorption in a Rat Model of Chronic Kidney Disease–Mineral Bone Disorder
Authors: Vorland Colby J , Biruete Annabel , Lachcik Pamela J , Srinivasan Shruthi , Chen Neal X , Moe Sharon M , Hill Gallant Kathleen M 
Published: October 2019

ABSTRACT
The Cy/+ rat has been characterized as a progressive model of chronic kidney disease–mineral bone disorder (CKD-MBD). We aimed to determine the effect of kidney disease progression on intestinal phosphorus absorption and whole-body phosphorus balance in this model. A total of 48 Cy/+ (CKD) and 48 normal littermates (NL) rats were studied at two ages: 20 weeks and 30 weeks, to model progressive kidney function decline at approximately 50% and 20% of normal kidney function. Sodium-dependent and sodium-independent intestinal phosphorus absorption efficiency were measured by the in situ jejunal ligated loop method using 33P radioisotope. Our results show that CKD rats had slightly higher sodium-dependent phosphorus absorption compared to NL rats, and absorption decreased from 20 to 30 weeks. These results are in contrast to plasma 1,25OH2D, which was lower in CKD rats. Gene expression of the major intestinal phosphorus transporter, NaPi-2b, was not different between CKD and NL rats in the jejunum but was lower in CKD rats versus NL rats in the duodenum. Jejunal ligated loop phosphorus absorption results are consistent with percent net phosphorus absorption results obtained from metabolic balance: higher net percent phosphorus absorption values in CKD rats compared with NL, and lower values in 30-week-olds compared with 20-week-olds. Phosphorus balance was negative (below zero) in CKD rats, significantly lower in 30-week-old rats compared with 20-week-old rats, and lower in CKD rats compared with NL rats at both ages. These results demonstrate no reduction in intestinal phosphorus absorption with progression of CKD despite lower 1,25OH2D status when assessed by an in situ ligated loop test, which is in contrast to the majority of in vitro studies, and if confirmed in further studies, could challenge the physiological relevance of in vitro findings. © 2019 American Society for Bone and Mineral Research.
The Associations Between Seven Different Types of Physical Activity and the Incidence of Fracture at Seven Sites in Healthy Postmenopausal UK Women
Authors: Armstrong Miranda EG , Lacombe Jason , Wotton Clare J , Cairns Benjamin J , Green Jane , Floud Sarah , Beral Valerie , Reeves Gillian K ,   for the Million Women Study Collaborators
Published: October 2019

ABSTRACT
There is a paucity of information on associations between specific types of physical activity and fracture risk at different sites in otherwise healthy postmenopausal women. Therefore, we examined risk of fracture at seven different sites associated with seven different types of physical activity in the population-based prospective UK Million Women Study. A total of 371,279 postmenopausal women (mean age 59.8 years), rating their health as good or excellent and reporting participation in walking, cycling, gardening, doing housework, yoga, dance, and sports club activities, were followed for site-specific incident fracture through record linkage to national databases on day-case and overnight hospital admissions. Cox regression yielded adjusted relative risks (RRs) and, because of the large number of statistical tests done, 99% confidence intervals (CIs) for fracture at seven different sites in relation to seven different physical activities. During an average follow-up of 12 years, numbers with a first site-specific fracture were as follows: humerus (2341), forearm (1238), wrist (7358), hip (4354), femur (not neck) (617), lower leg (1184), and ankle (3629). For upper limb fractures there was significant heterogeneity across the seven activity types (test for heterogeneity p = 0.004), with gardening more than 1 hour/week associated with a lower risk (RR = 0.91; 99% CI, 0.86 to 0.96; p &lt; 0.0001), whereas cycling more than 1 hour/week was associated with an increased risk (RR = 1.11; 99% CI, 1.00 to 1.23; p = 0.008). For fractures of the lower limb (including hip) there was no significant heterogeneity by type of activity, with significant approximately 5% to 15% reductions in risk associated with most activities, except cycling. For hip fractures, there was no significant heterogeneity by type of activity, but with significant 15% to 20% reductions in risk associated with walking for 1 hour/day and participating in yoga and sporting activities. Physical activity is a modifiable risk factor for fracture, but the effects differ between different types of activities and different fracture sites. © 2019 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.
Kinesin family member 18B: A contributor and facilitator in the proliferation and metastasis of cutaneous melanoma
Authors: Yan Hongmei , Zhu Changyou , Zhang Li 
Published: October 2019

AbstractMelanoma is the most aggressive type of cutaneous tumor and the occurrence of metastasis makes it resistant to almost all available treatment and becomes incorrigible. Hence, identifying metastasis‐related biomarkers and effective therapeutic targets will assist in preventing metastasis and ameliorating cutaneous melanoma. In our present study, we reported kinesin family member 18B (KIF18B) as a novel contributor in cutaneous melanoma proliferation and metastasis, and it was found to be of great significance in predicting the prognosis of cutaneous melanoma patients. Bioinformatics analysis based on ONCOMINE, The Cancer Genome Atlas, and Genotype‐Tissue Expression database revealed that KIF18B was highly expressed in cutaneous melanoma and remarkably correlated with unfavorable clinical outcomes. Consistently, the results of the quantitative real‐time polymerase chain reaction exhibited that the expression of KIF18B was significantly higher in cutaneous melanoma cell lines than that in normal cells. In vitro, biological assays found that knockdown of KIF18B in cutaneous melanoma cells noticeably repressed cell proliferation, migration, and invasion, while inducing cell apoptosis. Moreover, the protein expression of E‐cadherin was enhanced while the expression of N‐cadherin, vimentin, and Snail was decreased in M14 cells after knocking down KIF18B. In addition, the phosphorylation of phosphoinositide 3‐kinase (PI3K) and extracellular‐signal‐regulated kinase (ERK) was significantly suppressed in M14 cells with silenced KIF18B. Above all, our results indicated that the repression of cutaneous melanoma cell migration and proliferation caused by KIF18B depletion suggested an oncogenic role of KIF18B in cutaneous melanoma, which acts through modulating epithelial‐mesenchymal transition and ERK/PI3K pathway.