bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structural Reevaluation of the Electrophilic Hypervalent Iodine Reagent for Trifluoromethylthiolation Supported by the Crystalline Sponge Method for X‐ray Analysis
Authors: Vinogradova Ekaterina V. , Müller Peter , Buchwald Stephen L. 
Published: February 2014

AbstractHypervalent iodine λ3‐benziodoxoles are common electrophilic transfer reagents known for their enhanced stability compared to their non‐cyclic analogues. Herein we present data showing that chlorobenziodoxole reacts with two different thiolate nucleophiles (thiocyanate and trifluoromethylthiolate), resulting in the formation of stable thioperoxy complexes rather than the expected benziodoxole derivatives. We further report a revised structure for the earlier described electrophilic trifluoromethylthiolation reagent (1), which was previously believed to contain the benziodoxole framework. Our findings, which are based on a combination of analytical techniques, including the recently introduced crystalline sponge method for X‐ray analysis, unambiguously demonstrate that 1 is a thioperoxy compound both in solution and the solid state.
On the Stability of a POCsp3OP‐Type Pincer Ligand in Nickel(II) Complexes
Authors: Hao Jingjun , Mougang‐Soumé Berline , Vabre Boris , Zargarian Davit 
Published: February 2014

AbstractWe describe the results of a study on the stabilities of pincer‐type nickel complexes relevant to catalytic hydroalkoxylation and hydroamination of olefins, CC and CX couplings, and fluorination of alkyl halides. Complexes [(POCsp3OP)NiX] are stable for X=OSiMe3, OMes (Mes=1,3,5‐Me3C6H2), NPh2, and CCH, whereas the O(tBu) and N(SiMe3)2 derivatives decompose readily. The phenylacetylide derivative transforms gradually into the zero‐valent species cis‐[{κP,κC,κC′‐(iPr2POCH2CHCH2)}Ni{η2,κC,κC′‐(iPr2P(O)CCPh)}]. Likewise, attempts to prepare [(POCsp3OP)NiF] gave instead the zwitterionic trinuclear species [{(η3‐allyl)Ni}2‐{μ,κP,κO‐(iPr2PO)4Ni}]. Characterization of these two complexes provides concrete examples of decomposition processes that can dismantle POCsp3OP‐type pincer ligands by facile CO bond rupture. These results serve as a cautionary tale for the inherent structural fragility of pincer systems bearing phosphinite donor moieties, and provide guidelines on how to design more robust analogues.
Mesoporous Prussian Blue Analogues: Template‐Free Synthesis and Sodium‐Ion Battery Applications
Authors: Yue Yanfeng , Binder Andrew J. , Guo Bingkun , Zhang Zhiyong , Qiao Zhen‐An , Tian Chengcheng , Dai Sheng 
Published: February 2014

AbstractThe synthesis of mesoporous Prussian blue analogues through a template‐free methodology and the application of these mesoporous materials as high‐performance cathode materials in sodium‐ion batteries is presented. Crystalline mesostructures were produced through a synergistically coupled nanocrystal formation and aggregation mechanism. As cathodes for sodium‐ion batteries, the Prussian blue analogues all show a reversible capacity of 65 mA h g−1 at low current rate and show excellent cycle stability. The reported method stands as an environmentally friendly and low‐cost alternative to hard or soft templating for the fabrication of mesoporous materials.
Redox‐Triggered CC Coupling of Diols and Alkynes: Synthesis of β,γ‐Unsaturated α‐Hydroxyketones and Furans by Ruthenium‐Catalyzed Hydrohydroxyalkylation
Authors: McInturff Emma L. , Nguyen Khoa D. , Krische Michael J. 
Published: February 2014

AbstractDirect ruthenium‐catalyzed CC coupling of alkynes and vicinal diols to form β,γ‐unsaturated ketones occurs with complete levels of regioselectivity and good to complete control over the alkene geometry. Exposure of the reaction products to substoichiometric quantities of p‐toluenesulfonic acid induces cyclodehydration to form tetrasubstituted furans. These alkyne‐diol hydrohydroxyalkylations contribute to a growing body of merged redox‐construction events that bypass the use of premetalated reagents and, hence, stoichiometric quantities of metallic by‐products.
Blends of poly(3‐hydroxybutyrate) with poly(β‐alanine) and its derivatives
Authors: Çatıker Efkan , Sancaktar Erol 
Published: February 2014

ABSTRACTNanofibers and films of poly(3‐hydroxybutyrate) (PHB)/nylon 3 [poly(β‐alanine) (N3)], PHB/poly(α‐methyl‐β‐alanine) (2mN3), and PHB/poly(β‐methyl‐β‐alanine) (3mN3) blends were prepared by electrospinning and film‐casting techniques, respectively. The miscibility of the blends was studied by Fourier transform infrared spectrometry, differential scanning calorimetry, thermogravimetric analysis, and X‐ray diffraction (XRD). The electrospinnability of the blends was studied by scanning electron microscopy. Some characteristic IR absorption bands of the components in the blends shifted gradually with changes in the compositions. The melting temperature and decomposition temperature of PHB decreased gradually with increasing fractions of N3, 2mN3, and 3mN3. The XRD spectra of all of the blends exhibited peaks with lower intensities compared to those of the neat species. The suppression of PHB crystallinity in the blends after blending was attributed to the disruption of its crystal lattice and the prevention of recrystallization of each component by means of other components and segmental interactions between the components in the amorphous phase. Thermal, spectroscopic, and optical analyses of the polymer blends revealed that the polymers were miscible with good compatibility, and this could have improved the scaffold properties of PHB. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40484.
Characterization of rheological and thermophysical properties of HDPE–wood composite
Authors: Tazi Mosfafa , Erchiqui Fouad , Godard François , Kaddami Hamid , Ajji Abdellah 
Published: February 2014

ABSTRACTThe objective of this study is to develop a new biocomposite material with high deformation ability. In this regard, the thermal, rheological, and thermophysical properties of this new composite were characterized as a function of temperature and filler concentration. High density polyethylene (HDPE) was the matrix of this new composite which was reinforced with six sawdust concentrations 0%, 20%, 30%, 40%, 50%, and 60%. Maleic anhydride grafted polyethylene (PE‐g‐MA) was used as coupling agent. Addition of sawdust with PE‐g‐MA increased significantly the complex viscosity, the storage modulus (G′), and loss modulus (G″) of the matrix. The superposition of the complex viscosity curves using temperature dependent shift factor, allowed the construction of a viscosity master curve covering a wide range of temperatures. Arrhenius law was used for the relationship of the shift factor to temperature. Furthermore, method of Van Gurp and Palmen (tan delta vs. G*) is also used to control the time–temperature superposition. The experimental results can be well fitted with the cross rheological model which allowed the prediction of the thermorheological properties of the composites over a broad frequency range. By increasing wood concentration, both the activation energy and relaxation time for the biocomposites determined using, respectively, the Arrhenius law and the cole–cole rule increased. By contrast, specific heat of the matrix decreased with sawdust addition while its dimensional stability improved. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40495.
Predicting use of habitat patches by spawning horseshoe crabs (Limulus polyphemus) along a complex coastline with field surveys and geospatial analyses
Authors: Landi Alicia A. , Vokoun Jason C. , Howell Penelope , Auster Peter 
Published: February 2014

Abstract

This research described coastal habitat characteristics at a landscape scale and followed a geospatial modelling approach to predict the probability of habitat use by the population of Atlantic horseshoe crabs (Limulus polyphemus) in Long Island Sound (LIS, USA). This approach was developed to aid in decision‐making regarding management of horseshoe crab spawning locations.
Geospatial data layers were created within which beach slope, wave exposure, surface substrate type, and distance from offshore aggregations of crabs (i.e. hotspots) were summarized for beaches in the western, central, and eastern regions of the Connecticut coast of LIS.
Spawning abundances derived from field surveys conducted in May and June of 2009 and 2010 were used with remotely‐sensed habitat characteristics to develop a resource selection function from a candidate model set based on polytomous logistic regression.
A single best model (Akaike weight = 0.97) for predicting the probability of habitat use by spawning horseshoe crabs was selected using an information‐theoretic approach. The parameter estimates predicted a greater probability of habitat use with increasing slope, decreasing wave exposure, and decreasing distance from offshore hotspots.
Small ‘pocket’ beaches surrounded by rocky headlands, marshes, and developed areas are the typical habitat available to support horseshoe crab spawning in LIS. As spawning densities in LIS are relatively small and suitable spawning habitat is fragmented, geospatial methods are especially useful for identifying high‐use sites and maximizing the conservation value of management actions. Copyright © 2014 John Wiley & Sons, Ltd.
Porous Protein Crystals as Catalytic Vessels for Organometallic Complexes
Authors: Tabe Hiroyasu , Abe Satoshi , Hikage Tatsuo , Kitagawa Susumu , Ueno Takafumi 
Published: February 2014

AbstractPorous protein crystals, which are protein assemblies in the solid state, have been engineered to form catalytic vessels by the incorporation of organometallic complexes. Ruthenium complexes in cross‐linked porous hen egg white lysozyme (HEWL) crystals catalyzed the enantioselective hydrogen‐transfer reduction of acetophenone derivatives. The crystals accelerated the catalytic reaction and gave different enantiomers based on the crystal form (tetragonal or orthorhombic). This method represents a new approach for the construction of bioinorganic catalysts from protein crystals.
The Influence of the Framework: An Anion‐Binding Study Using Fused [n]Polynorbornanes
Authors: Long Benjamin M. , Pfeffer Frederick M. 
Published: February 2014

AbstractA series of bis‐thiourea‐functionalized [n]polynorbornane hosts (1–6) with increasing size were synthesized and their anion‐binding properties were evaluated by using 1H NMR spectroscopic titration and Job’s plot analysis. The larger bis‐thiourea‐[3]polynorbornane scaffolds 4 and 5 bound acetate in a 1:1 (cooperative) arrangement, whereas the corresponding smaller norbornane host 2, identical in preorganization, bound acetate in a 1:2 (independent) arrangement. In contrast, the size of the framework had no influence on the binding of dihydrogenphosphate. These results clearly highlight the subtle influence that the framework itself can have on host–guest interactions.
A stochastic multimodal reliable network design problem under adverse weather conditions
Authors: Uchida Kenetsu , Sumalee Agachai , Ho H. W. 
Published: February 2014

SummaryThis paper formulates a network design problem (NDP) for finding the optimal public transport service frequencies and link capacity expansions in a multimodal network with consideration of impacts from adverse weather conditions. The proposed NDP aims to minimize the sum of expected total travel time, operational cost of transit services, and construction cost of link capacity expansions under an acceptable level of variance of total travel time. Auto, transit, bus, and walking modes are considered in the multimodal network model for finding the equilibrium flows and travel times. In the proposed network model, demands are assumed to follow Poisson distribution, and weather‐dependent link travel time functions are adopted. A probit‐based stochastic user equilibrium, which is based on the perceived expected travel disutility, is used to determine the multimodal route of the travelers. This model also considers the strategic behavior of the public transport travelers in choosing their routes, that is, common‐line network. Based on the stochastic multimodal model, the mean and variance of total travel time are analytical estimated for setting up the NDP. A sensitivity‐based solution algorithm is proposed for solving the NDP, and two numerical examples are adopted to demonstrate the characteristics of the proposed model. Copyright © 2014 John Wiley & Sons, Ltd.
Choline transporter‐like proteins CTLs/SLC44 family as a novel molecular target for cancer therapy
Authors: Inazu Masato 
Published: February 2014

ABSTRACTCholine is essential for the synthesis of the major membrane phospholipid phosphatidylcholine (PC), the methyl donor betaine and the neurotransmitter acetylcholine (ACh). Elevated levels of choline and up‐regulated choline kinase activity have been detected in various cancers. Thus, the intracellular accumulation of choline through choline transporters is the rate‐limiting step in phospholipid metabolism and a prerequisite for cancer cell proliferation. Previous studies have demonstrated abnormalities in choline uptake and choline phospholipid metabolism in cancer cells using the imaging of cancer with positron emission tomography (PET) and magnetic resonance spectroscopy (MRS). The aberrant choline metabolism in cancer cells is strongly correlated with their malignant progression. Using quantitative real‐time PCR, the mRNA expression of choline transporters was measured, and it was found that choline transporter‐like proteins CTLs/SLC44 family are highly expressed in various cancer cell lines. Choline uptake through CTLs is associated with cell viability, and the functional inhibition of CTLs could promote apoptotic cell death. Furthermore, non‐neuronal cholinergic systems that include CTLs‐mediated choline transport are associated with cell proliferation and their inhibition promotes apoptotic cell death in colon cancer, small cell lung cancer and human leukemic T‐cells. The identification of this new CTLs‐mediated choline transport system provides a potential new target for cancer therapy. Copyright © 2014 John Wiley & Sons, Ltd.
Pharmacokinetics of tolbutamide and its metabolite 4‐hydroxy tolbutamide in poloxamer 407‐induced hyperlipidemic rats
Authors: Choi Mi Ran , Kwon Mi Hye , Cho Yong Yeon , Choi Hye Duck , Kim Yu Chul , Kang Hee Eun 
Published: February 2014

ABSTRACTUnder hyperlipidemic conditions, there are likely to be alterations in the pharmacokinetics of CYP2C11 substrates following decreased expression of CYP2C11, which is homologous to human CYP2C9. The pharmacokinetics of tolbutamide (TB) and its metabolite 4‐hydroxy tolbutamide (4‐OHTB) were evaluated as a CYP2C11 probe after intravenous and oral administration of 10 mg/kg tolbutamide to poloxamer 407‐induced hyperlipidemic rats (HL rats). Changes in the expression and metabolic activity of hepatic CYP2C11 and the plasma protein binding of tolbutamide in HL rats were also evaluated. The total area under the plasma concentration–time curve (AUC) of tolbutamide in HL rats after intravenous administration was comparable to that in controls due to their comparable non‐renal clearance (CLNR). The free fractions of tolbutamide in plasma were comparable between the control and HL rats. The 4‐hydroxylated metabolite formation ratio (AUC4‐OHTB/AUCTB) in HL rats was significantly smaller than that in the control rats as a result of the reduced expression of hepatic CYP2C11 (by 15.0%) and decreased hepatic CLint (by 28.8%) for metabolism of tolbutamide to 4‐OHTB via CYP2C11. Similar pharmacokinetic changes were observed in HL rats after oral administration of tolbutamide. These findings have potential therapeutic implications, assuming that the HL rat model qualitatively reflects similar changes in patients with hyperlipidemia. Since other sulfonylureas in clinical use are substrates of CYP2C9, their hepatic CLint changes have the potential to cause clinically relevant pharmacokinetic changes in a hyperlipidemic state. Copyright © 2014 John Wiley & Sons, Ltd.
Effects of fluidity on the ensemble structure of a membrane embedded α‐helical peptide
Authors: Eagleburger Michael K. , Cooley Jason W. , JiJi Renee D. 
Published: February 2014

ABSTRACTMelittin, the main hemolytic component of honeybee venom, is unfolded in an aqueous environment and folds into an α‐helical conformation in a lipid environment. Membrane fluidity is known to affect the activity and structure of melittin. By combining two structurally sensitive optical methods, circular dichroism (CD) and deep‐ultraviolet resonance Raman spectroscopy (dUVRR), we have identified distinct structural fluctuations in melittin correlated with increased and decreased 1,2‐dimyristoyl‐sn‐glycero‐3‐phosphocholine bilayer fluidities. CD spectra have reduced intensity at temperatures above 22°C and high concentrations of the cholesterol analog 5α‐cholestan‐3β‐ol indicating distortions in the α‐helical structure under these conditions. No increase in the amide S is observed in the temperature‐dependent dUVRR spectra, suggesting an increase in 310‐helical structure with increasing temperatures above 22°C. However, incorporation of 25 mol% 5α‐cholestan‐3β‐ol resulted in a small increase in the amide S intensity indicating partial unfolding of melittin. © 2014 Wiley Periodicals, Inc. Biopolymers 101: 895–902, 2014.
Randomized clinical trial of single- versus multi-incision laparoscopic cholecystectomy
Authors: Jørgensen L N , Rosenberg J , Al-Tayar H , Assaadzadeh S , Helgstrand F , Bisgaard T 
Published: February 2014

Abstract

Background
There are no randomized studies that compare outcomes after single-incision (SLC) and conventional multi-incision (MLC) laparoscopic cholecystectomy under an optimized perioperative analgesic regimen.

Methods
This patient- and assessor-blinded randomized three-centre clinical trial compared SLC and MLC in women admitted electively with cholecystolithiasis. Outcomes were registered on the day of operation (day 0), on postoperative days 1, 2, 3 and 30, and 12 months after surgery. Blinding of the patients was maintained until day 3. The primary endpoint was pain on movement measured on a visual analogue scale, reported repeatedly by the patient until day 3.

Results
The intention-to-treat population comprised 59 patients in the SLC and 58 in the MLC group. There was no significant difference between the groups with regard to any of the pain-related outcomes, on-demand administration of opioids or general discomfort. Median duration of surgery was 32·5 min longer in the SLC group (P &lt; 0·001). SLC was associated with a reduced incidence of vomiting on day 0 (7 versus 22 per cent; P = 0·019). The incidences of wound-related problems were comparable. One patient in the SLC group experienced a biliary leak requiring endoscopic retrograde cholangiopancreatography. The rates of incisional hernia at 12-month follow-up were 2 per cent in both groups. Cosmetic rating was significantly improved after SLC at 1 and 12 months (P &lt; 0·001).

Conclusion
SLC did not significantly diminish early pain in a setting with optimized perioperative analgesic patient care. SLC may reduce postoperative vomiting. Registration number: NCT01268748 (http://www.clinicaltrials.gov).
Risk factors for anastomotic leakage and leak-related mortality after colonic cancer surgery in a nationwide audit
Authors: Bakker I S , Grossmann I , Henneman D , Havenga K , Wiggers T 
Published: February 2014

Abstract

Background
Surgical resection with restoration of bowel continuity is the cornerstone of treatment for patients with colonic cancer. The aim of this study was to identify risk factors for anastomotic leakage (AL) and subsequent death after colonic cancer surgery.

Methods
Data were retrieved from the Dutch Surgical Colorectal Audit. Patients undergoing colonic cancer resection with creation of an anastomosis between January 2009 to December 2011 were included. Outcomes were AL requiring reintervention and postoperative mortality following AL.

Results
AL occurred in 7·5 per cent of 15 667 patients. Multivariable analyses identified male sex, high American Society of Anesthesiologists (ASA) fitness grade, extensive tumour resection, emergency surgery, and surgical resection types such as transverse resection, left colectomy and subtotal colectomy as independent risk factors for AL. A defunctioning stoma was created in a small group of patients, leading to a lower risk of leakage. The mortality rate was 4·1 per cent overall, and was significantly higher in patients with AL than in those without leakage (16·4 versus 3·1 per cent; P &lt; 0·001). Multivariable analyses identified older age, high ASA grade, high Charlson score and emergency surgery as independent risk factors for death after AL. The adjusted risk of death after AL was twice as high following right compared with left colectomy.

Conclusion
The elderly and patients with co-morbidity have a higher risk of death after AL. Accurate preoperative patient selection, intensive postoperative surveillance for AL, and early and aggressive treatment of suspected leakage is important, especially in patients undergoing right colectomy.
Interferon γ and plasminogen activator inhibitor 1 regulate adhesion formation after partial hepatectomy
Authors: Ohashi K , Yoshimoto T , Kosaka H , Hirano T , Iimuro Y , Nakanishi K , Fujimoto J 
Published: February 2014

Abstract

Background
The pathophysiology of intra-abdominal adhesions has not been studied extensively. The aim of this study was to elucidate the molecular mechanisms underlying adhesion formation in a murine model and in patients undergoing hepatectomy.

Methods
Partial hepatectomy was performed using bipolar forceps in mice. Wild-type mice, antibodies to CD4 and interferon (IFN) γ, IFN-γ, natural killer T (NKT) cells and plasminogen activator inhibitor (PAI) 1 knockout (KO) mice were used. Recombinant hepatocyte growth factor (HGF) was tested for its ability to prevent adhesions. Liver specimens were obtained during surgery from patients undergoing hepatectomy. Adhesion formation was evaluated using a scoring system that ranged from 0 (no adhesions) to 5 (severe adhesions). Levels of IFN-γ and PAI-1 mRNA, and protein concentration of PAI-I were measured, and fluorescence immunostaining was performed.

Results
Adhesion formation depended on IFN-γ produced by NKT cells, and NKT KO mice developed few adhesions (mean(s.d.) 1·7(0·3) versus 4·6(0·4) in wild-type mice; P = 0·037). In wild-type mice, the level of PAI-1 mRNA increased after hepatectomy, followed by a decrease in the tissue plasminogen activator (tPA) mRNA level. Adhesion formation was inhibited completely in PAI-1 KO mice (0(0) versus 4·1(0·8) in wild-type mice; P = 0·002). HGF inhibited formation of abdominal adhesions after hepatectomy by reducing IFN-γ and PAI-1 levels, and increasing tPA levels compared with those in mice treated with phosphate-buffered saline (P &lt; 0·001, P = 0·002 and P = 0·035 respectively). In human liver specimens, NKT cells accumulated in the liver after hepatectomy, and PAI-1 expression was increased 5·25-fold (P = 0·030).

Conclusion
IFN-γ is a key molecule for abdominal adhesion formation after hepatectomy, acting via the reciprocal balance of PAI-1 and tPA. This molecular mechanism may also regulate adhesion formation in patients following hepatectomy. HGF inhibited formation of adhesions by regulating IFN-γ and PAI-1, suggesting that it may be an important target for prevention of adhesions after hepatectomy.