bluuebunny/crossref_metadata_2025 huggingface dataset:
A phase 1 dose escalation study of idarubicin combined with methotrexate, vindesine, and prednisolone for untreated elderly patients with primary central nervous system lymphoma: The GOELAMS LCP 99 trial
Authors: Olivier Gaelle , Clavert Aline , Lacotte‐Thierry Laurence , Gardembas Martine , Escoffre‐Barbe Martine , Brion Annie , Cumin Isabelle , Legouffe Eric , Solal‐Celigny Philippe , Chabin Michèle , Ingrand Pierre , Colombat Philippe , Delwail Vincent
Published: July 2014

Treatment of primary central nervous system lymphoma (PCNSL) in elderly patients remains unsatisfactory. To develop a new high‐dose methotrexate (HD‐MTX)‐based regimen including idarubicin, a phase 1 multicenter dose escalation study was conducted to determine the maximum‐tolerated dose (MTD) of idarubicin. Thirty‐five immunocompetent patients with PCNSL were enrolled. The median age was 65 years (range, 60–70 years). MTX and vindesine (VDS) were given at the fixed dose of 3 g/m2 (6‐hr intravenous [IV]) and 3 mg/m2 IV on day 1, respectively. Prednisolone (PRED) was given at the fixed dose of 60 mg/m2 (IV or orally) on days 1–5. Idarubicin was escalated in increments of 2 mg/m2 with doses ranging from 12–18 mg/m2 IV on day 1. Treatment was repeated three times every 3 weeks. Dose‐limiting toxicity (DLT) was defined as grade 4 neutropenia for more than 7 days, thrombocytopenia grade 4 or nonhaematological toxicity more than grade 2. The MTD of idarubicin was reached at 16 mg/m2. At this level, the main haematological toxicities were thrombocytopenia grade 4: 5% and neutropenia grade 3 or 4 (52%); the main nonhaematological toxicities were grade 3 or 4 infectious disease (5%) and grade 2 renal failure (9%). For the study population, median overall and progression‐free survival were 19 and 13 months, respectively. Our study suggests that the MTD of idarubicin in combination with HD‐MTX, VDS, and PRED, should be 16 mg/m2. Further studies will be necessary to challenge a standard treatment in elderly patients with PCNSL. Am. J. Hematol. 89:1024–1029, 2014. © 2014 Wiley Periodicals, Inc.
Application of Regio‐ and Stereoselective Functional Group Transformations of Chiral Aziridine‐2‐carboxylates
Authors: Ha Hyun‐Joon , Jung Jae‐Hoon , Lee Won Koo
Published: July 2014

Chiral aziridine‐2‐carboxylates have two important functional groups, the carboxylate group and aziridine ring, that are useful for synthetic purposes. As both (2R)‐ and (2S)‐aziridine‐2‐carboxylates were commercialized in optically pure forms, we have studied to extend their synthetic utilities for the construction of various nitrogen‐containing molecules. The C2 ester group can be transformed into aldehydes, alcohols, amides, ketones, β‐ketoesters, and amines bearing diverse substituents with defined stereochemistry in high yields. In particular, ring‐opening reactions of aziridines are carried out in regio‐ and stereoselective manners toward α‐ or β‐amino cyclic and acyclic compounds in optically pure forms. The highlight of this chemistry based on the regio‐ and stereoselective functional‐group transformations of aziridine‐2‐carboxylates is exemplified by efficient and highly stereoselective syntheses of many biologically important amines, including natural products.
Domino Knoevenagel Condensation/Aza‐Ene Addition/N‐Cyclization Route to Functionalized Imidazo[1,2‐a]pyridines and Pyrido[1,2‐a]pyrimidines
Authors: Sivakumar Sathiyamoorthi , Kumar Raju Ranjith
Published: July 2014

A highly efficient and facile route to imidazo[1,2‐a]pyridines and pyrido[1,2‐a]pyrimidines is described by using the three‐component reaction of aroyl acetonitriles, nitroketene aminals, and either isatins or aromatic aldehydes in the presence of Et3N. This one‐pot strategy occurs in a single step and involves a domino Knoevenagel condensation/aza‐ene addition/imine–enamine tautomerization/chemoselective N‐cyclization sequence of reactions to afford the products in excellent yields without the need for purification by column chromatography.
Self‐Assembled Isoporous Block Copolymer Membranes with Tuned Pore Sizes
Authors: Yu Haizhou , Qiu Xiaoyan , Nunes Suzana P. , Peinemann Klaus‐Viktor
Published: July 2014

The combination of nonsolvent‐induced phase separation and the self‐assembly of block copolymers can lead to asymmetric membranes with a thin highly ordered isoporous skin layer. The effective pore size of such membranes is usually larger than 15 nm. We reduced the pore size of these membranes by electroless gold deposition. We demonstrate that the pore sizes can be controlled precisely between 3 and 20 nm leading to a tunable sharp size discrimination in filtration processes. Besides fractionation of nanoparticles and biomaterials, controlled drug delivery is an attractive potential application.
Niobium(V) Saponite Clay for the Catalytic Oxidative Abatement of Chemical Warfare Agents
Authors: Carniato Fabio , Bisio Chiara , Psaro Rinaldo , Marchese Leonardo , Guidotti Matteo
Published: July 2014

A NbV‐containing saponite clay was designed to selectively transform toxic organosulfur chemical warfare agents (CWAs) under extremely mild conditions into nontoxic products with reduced environmental impact. Thanks to the insertion of NbV sites within the saponite framework, a bifunctional catalyst with strong oxidizing and acid properties was obtained. Remarkable activity and high selectivity were observed for the oxidative abatement of (2‐chloroethyl)ethyl sulfide (CEES), a simulant of sulfur mustard, at room temperature with aqueous hydrogen peroxide. This performance was significantly better compared to a conventional commercial decontamination powder.
Aligning Electronic and Protonic Energy Levels of Proton‐Coupled Electron Transfer in Water Oxidation on Aqueous TiO2
Authors: Cheng Jun , Liu Xiandong , Kattirtzi John A. , VandeVondele Joost , Sprik Michiel
Published: July 2014

The high overpotential in water oxidation on anodes is a limiting factor for the large‐scale application of photoelectrochemical cells. To overcome this limitation, it is essential to understand the four proton‐coupled electron transfer (PCET) steps in the reaction mechanism and their implications to the overpotential. Herein, a simple scheme to compute the energies of the PCET steps in water oxidation on the aqueous TiO2 surface using a hybrid density functional is described. An energy level diagram for fully decoupled electron‐ and proton‐transfer reactions in which both electronic and protonic levels are placed on the same potential scale is also described. The level diagram helps to visualize the electronic and protonic components of the overpotential, and points out what are needed to improve. For TiO2, it is found that its catalytic activity is due to aligning the protonic energy levels in the PCET steps, while improving the activity requires also aligning the electronic levels.
Catalytic Enantioselective CH Functionalization of Alcohols by Redox‐Triggered Carbonyl Addition: Borrowing Hydrogen, Returning Carbon
Authors: Ketcham John M. , Shin Inji , Montgomery T. Patrick , Krische Michael J.
Published: July 2014

The use of alcohols and unsaturated reactants for the redox‐triggered generation of nucleophile–electrophile pairs represents a broad, new approach to carbonyl addition chemistry. Discrete redox manipulations that are often required for the generation of carbonyl electrophiles and premetalated carbon‐centered nucleophiles are thus avoided. Based on this concept, a broad, new family of enantioselective CC coupling reactions that are catalyzed by iridium or ruthenium complexes have been developed, which are summarized in this Minireview.
Thermosetting polyurethane‐multiwalled carbon nanotube composites: Thermomechanical properties and nanoindentation
Authors: Lopes Magnovaldo Carvalho , de Castro Vinicius Gomide , Seara Luciana Moreira , Diniz Vitor Perige Almeida , Lavall Rodrigo Lassarote , Silva Glaura Goulart
Published: July 2014

In this study, composites based on a thermoset polyurethane elastomer (PU) and multiwalled carbon nanotubes (MWCNT) in the case of a PU of high elastic modulus (>200 MPa) are analyzed for the first time. As‐grown and modified nanotubes with 4 wt % of oxygenated functions (MWCNT‐ox) were employed to compare their effect on composite properties and maxima mechanical properties (elastic modulus and tensile strength) were reached at 0.5 wt % of MWCNT‐ox. Furthermore, by examining the morphology using optical and electron microscopies better dispersion and interaction of the nanotube‐matrix was observed for this material. DMTA data supports the observation of an increase in the glass transition temperature of ∼20°C in the nanocomposites compared with the thermoset PU, which is an important result because it shows extended reliability in extreme environments. Finally, nanoindentation tests allowed a comparison with the conventional mechanical tests by measuring the elastic modulus and hardness at the subsurface of PU and the nanocomposites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41207.
Polyols and polyurethanes prepared from epoxidized soybean oil ring‐opened by polyhydroxy fatty acids with varying OH numbers
Authors: Chen Ruqi , Zhang Chaoqun , Kessler Michael R.
Published: July 2014

Bio‐based polyols from epoxidized soybean oil and different fatty acids were successfully prepared using a solvent‐free method in order to investigate the effect of the polyols' OH numbers on the thermal and mechanical properties of the polyurethanes prepared using them. Epoxidized soybean oil/epoxidized linseed oil was ring‐opened by methanol/glycol followed by saponification to prepare polyhydroxy fatty acids. These fatty acids and epoxidized soybean oil were then used for further solvent‐free ring‐opening reactions with DBU as catalyst, which facilitated the carboxylic ring‐opening. Gel permeation chromatography revealed that a molar ratio of carboxylic acid from polyhydroxy fatty aicds and epoxy group of 0.5 : 1 resulted in optimized polyols containing the smallest amounts of residual starting materials. The obtained polyols had varying OH numbers and the acquired polyurethane films were comprehensively characterized. With increasing OH number of the polyols the PUs displayed an increase in crosslinking density, glass transition temperature (Tg), tensile strength and Young's modulus, and a decrease in elongation and toughness. This work provides Supporting Information on the effect of OH number of polyols obtained via a solvent‐free ring‐opening method on the mechanical and thermal properties of polyurethanes, of particular interest when designing PU products for specific purposes. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41213.
A New Robust Adaptive Control of Uncertain Nonlinear Systems and Pendulum Application
Authors: Liu Zhitao , Su Hongye , Pan Shuwen
Published: July 2014

A new robust adaptive control of uncertain nonlinear systems is proposed in this paper. The proposed method combines sliding mode control with the immersion and invariance (I&I) adaptive scheme, and it has more available degrees of freedom than using the backstepping scheme. Via the proposed method, a class of nonlinear systems with mismatched parametric perturbations can be rendered asymptotically stable and the performance of the system can also be improved. Finally, the proposed method is applied to a simple pendulum with motor dynamics, and simulation results show the effectiveness and performance of the proposed method.
pTH Moment Exponential Stability of Stochastic Partial Differential Equations with Poisson Jumps
Authors: Yang Xuetao , Zhu Quanxin
Published: July 2014

In this paper, we study a class of stochastic partial differential equations with Poisson jumps, which is more realistic for establishing mathematical models since it has been widely applied in many fields. Under a reasonable condition, we not only establish the existence and uniqueness of the mild solution for the investigated system but also prove that it is pth moment exponentially stable by using the fixed point theory. Then, based on the well‐known Borel‐Cantelli lemma, further, we prove that the mild solution is almost surely pth moment exponentially stable. Our results improve and generalize those given in the previous literature, in particular, the Lyapunov direct method and successive approximation method. Finally, we give an example to illustrate the effectiveness of the obtained results.
Passivity, Feedback Equivalence and Global Stabilization of Nonlinear Markovian Jump Systems
Authors: Lin Zhongwei , Liu Jizhen , Niu Yuguang
Published: July 2014

This paper combines the passivity theory with geometric control theory for nonlinear Markovian jump systems. The key point concentrates on taking the appropriate coordinate changes following with the Markovian switchings. Based on this concept, we investigate the passivity, feedback equivalence and global stabilization problems, which implies that under a proposed strongly minimum‐phase condition, the nonlinear Markovian jump system is feedback equivalent to a passive system. A numerical example is presented to illustrate the effectiveness of our results.
Delay‐ and Packet‐Disordering‐Dependent H∞ Output Tracking Control for Networked Control Systems
Authors: Song Yan , Wang Jingcheng
Published: July 2014

This paper is concerned with the problem of H∞ output tracking control for networked control systems (NCSs) with network‐induced delay and packet disordering. Different from the results in existing literature, the controller design in this paper is both delay‐ and packet‐disordering‐dependent. Based on the different cases of consecutive predictions, the networked output tracking system is modeled into a switched system. Moreover, by the corresponding switching‐based Lyapunov functional approach, a linear matrix inequality (LMI)‐based procedure is proposed for designing state‐feedback controllers, which guarantees that the output of the closed‐loop NCSs tracks the output of a given reference model well in the H∞ sense. In addition, the proposed method can be applied variously due to all kinds of prediction numbers of the consecutive disordering packet have been considered, and the designed controller is based on the prediction case in the last transmission interval, which brings about less conservatism. Finally numerical examples and simulations are used to illustrate the effectiveness and validity of the proposed switching‐based method and the delay‐ and packet‐disordering‐dependent H∞ output tracking controller design.
Fuzzy Interval TSK Type‐2 Modeling with Parameterized Conjunctors
Authors: Aras Ayse Cisel , Kaynak Okyay
Published: July 2014

In this study, a novel approach is described to the design of an interval type‐2 fuzzy neural system (IT2 FNS). It differs from the classical IT2 FNS in its use of parameterized conjunctors. In the optimization of the IT2 FNS, the membership functions are kept fixed and only the parameters of the conjunctors and the parameters in the consequent are tuned. In this study, the gradient based learning algorithm is used. The approach is tested for the modeling of a benchmark nonlinear function and for the wheel slip control of a quarter car model (QCM). In the stated applications, in the absence of any expert knowledge, some knowledge about the system is gained by the use of the interval type‐2 fuzzy c‐means (IT2 FCM) clustering algorithm. Nevertheless, this requires the number of classes to be known beforehand. To alleviate this problem, some validity indices that have been suggested in the literature and a novel validity index that carries less computational burden are considered to determine the number of classes and the number of fuzzy rules. Simulation studies are presented and compared with the results from the literature.
Biomarker-based treatment selection in early-stage rectal cancer to promote organ preservation
Authors: Leong K J , Beggs A , James J , Morton D G , Matthews G M , Bach S P
Published: July 2014

Background

Total mesorectal excision (TME) remains commonplace for T1–2 rectal cancer owing to fear of undertreating a small proportion of patients with node-positive disease. Molecular stratification may predict cancer progression. It could be used to select patients for organ-preserving surgery if specific biomarkers were validated.

Methods

Gene methylation was quantified using bisulphite pyrosequencing in 133 unirradiated rectal cancer TME specimens. KRAS mutation and microsatellite instability status were also defined. Molecular parameters were correlated with histopathological indices of disease progression. Predictive models for nodal metastasis, lymphovascular invasion (LVI) and distant metastasis were constructed using a multilevel reverse logistic regression model.

Results

Methylation of the retinoic acid receptor β gene, RARB, and that of the checkpoint with forkhead and ring finger gene, CHFR, was associated with tumour stage (RARB: 51·9 per cent for T1–2 versus 33·9 per cent for T3–4, P < 0·001; CHFR: 5·5 per cent for T1–2 versus 12·6 per cent for T3–4, P = 0·005). Gene methylation associated with nodal metastasis included RARB (47·1 per cent for N− versus 31·7 per cent for N+; P = 0·008), chemokine ligand 12, CXCL12 (12·3 per cent for N− versus 8·9 per cent for N+; P = 0·021), and death-associated protein kinase 1, DAPK1 (19·3 per cent for N− versus 12·3 per cent for N+; P = 0·022). RARB methylation was also associated with LVI (45·1 per cent for LVI− versus 31·7 per cent for LVI+; P = 0·038). Predictive models for nodal metastasis and LVI achieved sensitivities of 91·1 and 85·0 per cent, and specificities of 55·3 and 45·3 per cent, respectively.

Conclusion

This methylation biomarker panel provides a step towards accurate discrimination of indolent and aggressive rectal cancer subtypes. This could offer an improvement over the current standard of care, whereby fit patients are offered radical surgery.
Surgical treatment of solid pseudopapillary neoplasms of the pancreas and risk factors for malignancy
Authors: Kim M J , Choi D W , Choi S H , Heo J S , Sung J-Y
Published: July 2014

Background

The aim of this study was to identify clinical predictors of malignancy and surgical strategies for pancreatic solid pseudopapillary neoplasm (SPN) by analysis of surgical outcomes at a single institution.

Methods

All patients who underwent surgery for SPN between 1995 and 2010 were identified. Histopathology slides of all patients were reviewed by a specialized pathologist and the neoplasms were classified according to the criteria of the World Health Organization 2010.

Results

Of the 106 patients identified, 85 (80·2 per cent) were female, and the median age was 36 (range 10–65) years. Median tumour size was 4·5 (range 1·0–15·0) cm. Some 17 patients (16·0 per cent) were classified as having a high-grade malignant SPN. Tumour size of at least 5 cm was associated with high-grade malignant potential (P = 0·022). Although lymph nodes were removed from 40 patients (37·7 per cent), there were no nodal metastases. A total of five patients underwent en bloc resection of adjacent structures, including two with portal vein involvement. After a median follow-up of 56·9 months, two patients with high-grade malignant SPN had evidence of tumour recurrence in the lymph nodes and liver.

Conclusion

SPN with a diameter of 5 cm or more is associated with a high-grade malignant phenotype. Complete surgical removal is associated with low recurrence rates.
Scientific writing: Strategies and tools for students and advisors
Authors: Singh Vikash , Mayer Philipp
Published: July 2014

Scientific writing is a demanding task and many students need more time than expected to finish their research articles. To speed up the process, we highlight some tools, strategies as well as writing guides. We recommend starting early in the research process with writing and to prepare research articles, not after but in parallel to the lab or field work. We suggest considering scientific writing as a team enterprise, which needs proper organization and regular feedback. In addition, it is helpful to select potential target journals early and to consider not only scope and reputation, but also decision times and rejection rates. Before submission, instructions to authors and writing guides should be considered, and drafts should be extensively revised. Later in the process editor's and reviewer's comments should be followed. Our tips and tools help students and advisors to structure the writing and publishing process, thereby stimulating them to develop their own strategies to success. © 2014 by The International Union of Biochemistry and Molecular Biology, 42(5):405–413, 2014.
Roles of resolvins in the resolution of acute inflammation
Authors: Qu Qing , Xuan Wenjuan , Fan Guo‐Huang
Published: July 2014

Resolution is an active process that terminates inflammatory response to maintain health. Acute inflammation and its timely resolution are important in host response to danger signals. Unresolved inflammation is associated with widely recurrent diseases. Resolvins, including the D and E series, are endogenous lipid mediators generated during the resolution phase of acute of inflammation from the ω‐3 PUFAs, DHA, and EPA. They have anti‐inflammatory and pro‐resolving properties that have been determined in many inflammation studies in animal models. In this review, we provide an updated overview of biosynthesis, actions, and signaling pathways of resolvins, thereby underscoring their diverse protective roles and introducing novel therapeutic strategies for inflammation‐associated diseases.
Growth factors have a protective effect on neomycin‐induced hair cell loss
Authors: Lou Xiangxin , Yuan Huihua , Xie Jing , Wang Xianliu , Yang Liangliang , Zhang Yanzhong
Published: July 2014

We have demonstrated that selected growth factors are involved in regulating survival and proliferation of progenitor cells derived from the neonatal rat organ of Corti (OC). The protective and regenerative effects of these defined growth factors on the injured organ of Corti were therefore investigated. The organ of Corti dissected from the Wistar rat pups (P3‐P5) was split into apical, middle, and basal parts, explanted and cultured with or without neomycin and growth factors. Insulin‐like growth factor‐1 (IGF‐1), fibroblast growth factor‐2 (FGF‐2), and epidermal growth factor (EGF) protected the inner hair cells (IHCs) and outer hair cells (OHCs) from neomycin ototoxicity. Using EGF, IGF‐1, and FGF‐2 alone induced no protective effect on the survival of auditory hair cells. Combining 2 growth factors (EGF + IGF‐1, EGF + FGF‐2, or IGF‐1 + FGF‐2) gave statistically protective effects. Similarly, combining all three growth factors effectively protected auditory hair cells from the ototoxic insult. None of the growth factors induced regeneration of hair cells in the explants injured with neomycin. Thus various combinations of the three defined factors (IGF‐1, FGF‐2, and EGF) can protect the auditory hair cells from the neomycin‐induced ototoxic damage, but no regeneration was seen. This offers a possible novel approach to the treatment of hearing loss.
Role of miR‐34c in ketamine‐induced neurotoxicity in neonatal mice hippocampus
Authors: Cao Shu‐e , Tian Jianmin , Chen Shengyang , Zhang Xiaoran , Zhang Yongqiang
Published: July 2014

Ketamine is a commonly used pediatric anesthetic, but it might affect development, or even induce neurotoxicity in the neonatal brain. We have used an in vivo neonatal mouse model to induce ketamine‐related neurotoxicity in the hippocampus, and found that miR‐34c, a microRNA associated with pathogenesis of Alzheimer's disease, was significantly upregulated during ketamine‐induced hippocampal neurodegeneration. Functional assay of silencing miR‐34c demonstrated that downregulation of miR‐34c activated PKC‐ERK pathway, upregulated anti‐apoptotic protein BCL2, and ameliorated ketamine‐induced apoptosis in the hippocampus. Cognitive examination with the Morris water maze test showed that ketamine‐induced memory impairment was significantly improved by miR‐34c downregulation. Thus, miR‐34c is important in regulating ketamine‐induced neurotoxicity in hippocampus.
Enhanced AuPd Activity in the Direct Synthesis of Hydrogen Peroxide using Nanostructured Titanate Nanotube Supports
Authors: Torrente‐Murciano Laura , He Qian , Hutchings Graham J. , Kiely Christopher J. , Chadwick David
Published: July 2014

Nanostructured supports with tubular morphologies can impose one dimensional external constraints to supported metal nanoparticles affording small sizes (<2 nm) with high dispersion. Specifically, the curvature and chemical environment of the external nanotube surface appears to play a key role in determining the morphology and stability of the supported AuPd nanoparticles. This strategy is presented as an alternative nanoparticle stabilisation approach rather than encapsulation within porous structures or the use of organic capping agents with associated diffusional limitations. Here, we report the enhancement achieved in the AuPd alloy reactivity for the direct synthesis of hydrogen peroxide when supported on titanate nanotubes (Ti‐NT) with a productivity above 11 600 mol kgmetal−1 h−1 afforded by the high metal–support interaction.
The Electrochemical Behavior of Phosphoric‐Acid‐Doped Poly(perfluorosulfonic Acid) Membranes
Authors: Aili David , Savinell Robert F. , Jensen Jens Oluf , Cleemann Lars N. , Bjerrum Niels J. , Li Qingfeng
Published: July 2014

Highly conductive phosphoric‐acid‐doped poly(perfluorosulfonic acid) membranes have long been known to malfunction in fuel cells. This is investigated and found to be due to failure of the anode, in which a limiting current is observed in the very low current‐density range. It is proposed that the strongly acidic sulfonic acid groups protonate the phosphoric acid under anhydrous conditions, forming excess proton defects that are involved in proton conduction by means of the vehicle mechanism. The slow back‐diffusion of phosphoric acid molecules as proton carriers thus limits the long‐range conductivity of the membranes during fuel cell operation. The hypothesis is experimentally verified using a specially designed half‐cell test.
t‐Na2(VO)P2O7: A 3.8 V Pyrophosphate Insertion Material for Sodium‐Ion Batteries
Authors: Barpanda Prabeer , Liu Guandong , Avdeev Maxim , Yamada Atsuo
Published: July 2014

Pyrophosphate oxyanionic framework compounds offer a great platform to investigate new battery materials. In our continuing effort to explore pyrophosphate cathodes for sodium‐ion batteries, we report, for the first time, the synthesis and use of tetragonal Na2(VO)P2O7 as a potential sodium‐ion insertion material. This material can be easily prepared by using a conventional solid‐state route at a relatively low temperature of 400 °C. Stabilizing as a tetragonal structure with an open framework, the material offers pathways for Na+ diffusion. The as‐synthesized material, with no further cathode optimization, yields a reversible capacity (Q) approaching 80 mAh g−1 (QTheoretical=93.4 mAh g−1) involving a one electron V5+/V4+ redox potential located at 3.8 V (vs. Na/Na+). Furthermore, the material exhibits decent rate kinetics and reversibility. Combining green synthesis and moderate electrochemical properties, t‐Na2(VO)P2O7 is reported as a new addition to the growing family of pyrophosphate cathodes for sodium‐ion batteries.
Photochemical Transformations Accelerated in Continuous‐Flow Reactors: Basic Concepts and Applications
Authors: Su Yuanhai , Straathof Natan J. W. , Hessel Volker , Noël Timothy
Published: July 2014

Continuous‐flow photochemistry is used increasingly by researchers in academia and industry to facilitate photochemical processes and their subsequent scale‐up. However, without detailed knowledge concerning the engineering aspects of photochemistry, it can be quite challenging to develop a suitable photochemical microreactor for a given reaction. In this review, we provide an up‐to‐date overview of both technological and chemical aspects associated with photochemical processes in microreactors. Important design considerations, such as light sources, material selection, and solvent constraints are discussed. In addition, a detailed description of photon and mass‐transfer phenomena in microreactors is made and fundamental principles are deduced for making a judicious choice for a suitable photomicroreactor. The advantages of microreactor technology for photochemistry are described for UV and visible‐light driven photochemical processes and are compared with their batch counterparts. In addition, different scale‐up strategies and limitations of continuous‐flow microreactors are discussed.
An Easy One‐Pot Synthesis of Diverse 2,5‐Di(2‐pyridyl)pyrroles: A Versatile Entry Point to Metal Complexes of Functionalised, Meridial and Tridentate 2,5‐Di(2‐pyridyl)pyrrolato Ligands
Authors: McSkimming Alex , Diachenko Vera , London Rachel , Olrich Kiara , Onie C. Jessica , Bhadbhade Mohan M. , Bucknall Martin P. , Read Roger W. , Colbran Stephen B.
Published: July 2014

A wide variety of 2,5‐di(2‐pyridyl)pyrroles (dppHs) substituted at the C3 and C4 positions of the pyrrole core were obtained by direct condensation of a 2‐pyridylcarboxaldehyde (2 equiv), an α‐methylene ketone with at least one electron‐withdrawing substituent and ammonium acetate. A novel 2,5‐di(1,10‐phenanthrolin‐2‐yl)pyrrole was also characterised. The dppHs provide a direct, quick entry to dipyridylpyrrolato (dpp−)–metal complexes. The meridial tridentate dpp− ligand is a useful anionic analogue of the terpyridyl ligand. The first (dpp)Ru complexes are described; the 3,4‐substitution of the central pyrrole significantly perturbs the potentials of the redox processes of these complexes. A [(dpp)Ru(bpy)(MeCN)]+ (bpy=2,2′‐bipyridine) complex is an electrocatalyst for the reductive disproportionation of carbon dioxide to carbon monoxide and the carbonate ion.
Metal‐Substituted Zeolitic Imidazolate Framework ZIF‐108: Gas‐Sorption and Membrane‐Separation Properties
Authors: Ban Yujie , Li Yanshuo , Peng Yuan , Jin Hua , Jiao Wenmei , Liu Xinlei , Yang Weishen
Published: July 2014

A series of dual‐metal zeolitic imidazolate framework (ZIF) crystals with SOD and RHO topologies was synthesised by metal substitution from ZIF‐108 (Zn(2‐nitroimidazolate)2, SOD topology) as the parent material. This was based on the concept that metal substitution of ZIF‐108 requires a much lower activation energy than homogenous nucleation owing to the metastability of ZIF‐108. In‐depth investigations of the formation processes of the daughter ZIFs indicated that the transformation of ZIF‐108 is a dissolution/heterogeneous nucleation process. Typical isostructural Co2+ substitution mainly occurs at the outer surface of ZIF‐108 and results in a core–shell structure. On the contrary, the Cu2+‐substituted ZIF has a RHO topology with a homogeneous distribution of Cu2+ ions in the structure. Substitution with Ni2+ resulted in a remarkable enhancement in adsorption selectivity toward CO2 over N2 by a factor of up to 227. With Co2+‐substituted nanoparticles as inorganic filler, a mixed matrix membrane based on polysulfone displayed greatly improved performance in the separation of H2/CH4, CO2/N2 and CO2/CH4.
Combining Topological and Steric Constraints for the Preparation of Heteroleptic Copper(I) Complexes
Authors: Mohankumar Meera , Monti Filippo , Holler Michel , Niess Frédéric , Delavaux‐Nicot Béatrice , Armaroli Nicola , Sauvage Jean‐Pierre , Nierengarten Jean‐François
Published: July 2014

Heteroleptic copper(I) complexes have been prepared from a macrocyclic ligand incorporating a 2,9‐diphenyl‐1,10‐phenanthroline subunit (M30) and two bis‐phosphines, namely bis[(2‐diphenylphosphino)phenyl] ether (POP) and 1,3‐bis(diphenylphosphino)propane (dppp). In both cases, the diphenylphosphino moieties of the PP ligand are too bulky to pass through the 30‐membered ring of M30 during the coordination process, hence the formation of C2v‐symmetrical pseudo‐rotaxanes is prevented. When POP is used, X‐ray crystal structure analysis shows the formation of a highly distorted [Cu(M30)(POP)]+ complex in which the POP ligand is only partially threaded through the M30 unit. This compound is poorly stable as the CuI cation is not in a favorable coordination environment due to steric constraints. By contrast, in the case of dppp, the bis‐phosphine ligand undergoes both steric and topological constraints and adopts a nonchelating coordination mode to generate [Cu2(M30)2(μ‐dppp)](BF4)2. This compound exhibits metal‐to‐ligand charge transfer (MLCT) emission characterized by a very large Stokes’ shift (≈200 nm) that is not attributed to a dramatic structural distortion between the ground and the emitting states but to very weak MLCT absorption transitions at longer wavelengths. Accordingly, [Cu2(M30)2(μ‐dppp)](BF4)2 shows unusually high luminescence quantum yields for CuI complexes, both in solution and in the solid state (0.5 and 7 %, respectively).
Diastereo‐ and Enantioselective Construction of a Bispirooxindole Scaffold Containing a Tetrahydro‐β‐carboline Moiety through an Organocatalytic Asymmetric Cascade Reaction
Authors: Dai Wei , Lu Han , Li Xin , Shi Feng , Tu Shu‐Jiang
Published: July 2014

The first catalytic asymmetric construction of a new class of bispirooxindole scaffold‐containing tetrahydro‐β‐carboline moiety has been established through chiral phosphoric acid‐catalyzed three‐component cascade Michael/Pictet–Spengler reactions of isatin‐derived 3‐indolylmethanols, isatins, and amino‐ester, which afforded structurally complex and diverse bispirooxindoles with one quaternary and one tetrasubstituted stereogenic centers in excellent stereoselectivities (all >95:5 diastereomeric ratio (d.r.), up to 98:2 enantiomeric ratio (e.r.)). This intriguing class of chiral bispirooxindoles integrated the two important structures of tetrahydro‐β‐carboline and bispirooxindole, both of them possessing significant bioactivities. This approach also combined the merits of asymmetric organocatalysis and multicomponent tandem reaction, which provided a unique strategy for the preparation of structurally rigid bispiro‐architectures with concomitant creation of multiple quaternary stereogenic centers.
Design of Stereoelectronically Promoted Super Lewis Acids and Unprecedented Chemistry of Their Complexes
Authors: Foroutan‐Nejad Cina , Vicha Jan , Marek Radek
Published: July 2014

A new family of stereoelectronically promoted aluminum and scandium super Lewis acids is introduced on the basis of state‐of‐the‐art computations. Structures of these molecules are designed to minimize resonance electron donation to central metal atoms in the Lewis acids. Acidity of these species is evaluated on the basis of their fluoride‐ion affinities relative to the antimony pentafluoride reference system. It is demonstrated that introduced changes in the stereochemistry of the designed ligands increase acidity considerably relative to Al and Sc complexes with analogous monodentate ligands. The high stability of fluoride complexes of these species makes them ideal candidates to be used as weakly coordinating anions in combination with highly reactive cations instead of conventional Lewis acid–fluoride complexes. Further, the interaction of all designed molecules with methane is investigated. All studied acids form stable pentavalent‐carbon complexes with methane. In addition, interactions of the strongest acid of this family with very weak bases, namely, H2, N2, carbon oxides, and noble gases were investigated; it is demonstrated that this compound can form considerably stable complexes with the aforementioned molecules. To the best of our knowledge, carbonyl and nitrogen complexes of this species are the first hypothetical four‐coordinated carbonyl and nitrogen complexes of aluminum. The nature of bonding in these systems is studied in detail by various bonding analysis approaches.
Efficient Asymmetric Synthesis of 1‐Cyano‐tetrahydroisoquinolines from Lipase Dual Activity and Opposite Enantioselectivities in α‐Aminonitrile Resolution
Authors: Sakulsombat Morakot , Vongvilai Pornrapee , Ramström Olof
Published: July 2014

Dual promiscuous racemization/amidation activities of lipases leading to efficient dynamic kinetic resolution protocols of racemic α‐aminonitrile compounds are described. α‐Amidonitrile products of high enantiomeric purity could be formed in high yields. Several lipases from different sources were shown to exhibit the dual catalytic activities, where opposite enantioselectivities could be recorded for certain substrates.
Amino‐Functionalized Pillar[5]arene
Authors: Strutt Nathan L. , Zhang Huacheng , Schneebeli Severin T. , Stoddart J. Fraser
Published: July 2014

The recently introduced pillar[n]arenes have provided chemists with receptors that, when incorporated into materials, confer unique properties upon them. The symmetrical rims and cylindrical shape of pillar[5]arene begs the question—can these pillar‐like receptors be linked covalently end‐to‐end in order to create tubular structures by a growth‐from‐template approach? In our efforts to produce these one‐dimensional extended structures, we have developed a new method of functionalizing pillar[5]arene in which one of the five hydroquinone units is converted into a diaminobenzoquinone analogue. The resulting diaminopillar[5]arene derivative, which undergoes a stereochemical inversion process that is slow on the 1H NMR timescale, can be chemically modified yet further in a direction that is orthogonal to the plane of its methylene bridging carbons through the formation of oxazole heterocycles. This strategy has been employed to create rigid oligomers that resemble one‐dimensional tubular arrays. As a proof‐of‐principle, a rigid pillar[5]arene dimer has been isolated and characterized in the solution state as a 1:1 complex with an extended viologen for which it acts as a receptor.
Development of a Small Molecule Probe Capable of Discriminating Cysteine, Homocysteine, and Glutathione with Three Distinct Turn‐On Fluorescent Outputs
Authors: Wang Feiyi , Guo Zhiqian , Li Xia , Li Xiuai , Zhao Chunchang
Published: July 2014

The simultaneous discrimination of Cys, Hcy, and GSH by a single probe is still an unmet challenge. The design and synthesis of a small molecule probe MeO‐BODIPY‐Cl (BODIPY=boron dipyrromethene) is presented, which can allow Cys, Hcy, and GSH to be simultaneously discriminated on the basis of three distinct fluorescence turn‐on responses. The probe reacts with these thiols to form sulfenyl‐substituted BODIPY, which is followed by intramolecular displacement to yield amino‐substituted BODIPY. The kinetic rate of the intramolecular displacement reaction determines the observed different sensing behavior. Therefore, the probe responds to Cys, Hcy, and GSH with fluorescence turn‐on colors of yellow, yellow and red, and red, respectively. With this promising feature in hand, the probe was successfully used in imaging of Cys, Hcy and GSH in living cells.
Plasmonic Activation of a Fluorescent Carbazole–Oxazine Switch
Authors: Garcia‐Amorós Jaume , Swaminathan Subramani , Sortino Salvatore , Raymo Françisco M.
Published: July 2014

The covalent attachment of a carbazole fluorophore to an oxazine photochrome permits the reversible activation of fluorescence under optical control. Ultraviolet irradiation with a pulsed laser opens the oxazine ring to shift bathochromically the absorption of the carbazole component. Concomitant visible illumination excites selectively the carbazole fluorophore of the photochemical product to produce fluorescence. The photogenerated and fluorescent species reverts spontaneously on a submicrosecond timescale to the initial nonemissive state of the carbazole–oxazine dyad. The photochemical and photophysical properties engineered into this particular molecular switch allow the convenient monitoring of plasmonic effects on photochemical reactions with fluorescence measurements. In close proximity to silver nanoparticles, visible illumination with a continuous‐wave laser also results in fluorescence activation. The metallic nanostructures enable the two‐photon excitation of the oxazine component to induce the photochromic transformation and then facilitate the one‐photon excitation of the photochemical product to generate fluorescence. Thus, these operating principles offer the opportunity to avoid altogether the need of pulsed ultraviolet irradiation to trigger the photochromic transformation and, instead, allow fluorescence activation with a single visible source operating at low illumination power.
Vectorial Diffusion for Facile Solution‐Processed Self‐Assembly of Insoluble Semiconductors: A Case Study on Metal Phthalocyanines
Authors: Wang Chengliang , Fang Yaoguo , Wen Liaoyong , Zhou Min , Xu Yang , Zhao Huaping , De Cola Luisa , Hu Wenping , Lei Yong
Published: July 2014

Solution processibility is one of the most intriguing properties of organic semiconductors. However, it is difficult to find a suitable solvent and solution process for most semiconductors. For example, metal phthalocyanines (MPcs) are only soluble in non‐volatile solvents, which prevent their applications from solution process. For the first time, vectorial diffusion is utilized for solution processing of MPcs. The obtained large F16CuPc and α‐phase CuPc crystals and the efficient phase separation of them suggest the vectorial diffusion process is as slow as a self‐assembly process, which is helpful to yield large crystals and purify the semiconductors. This method, which only uses common commercial solvents without any complex and expensive instruments and high‐temperature operation, provides a facile approach for purification of organic semiconductors and growth of their crystals in large quantities.
Evaluation of spectral, spectral‐element and finite‐element methods for the solution of the pellet equation
Authors: Solsvik Jannike , Jakobsen Hugo A.
Published: July 2014

Several numerical methods (orthogonal collocation, Galerkin, tau, least‐squares and least‐squares with a direct minimization algorithm) are applied to solve a linear diffusion–reaction problem. The spectral, finite‐element and spectral‐element frameworks are employed to investigate the methods. Overall, the Galerkin and tau methods are considered the most universal methods.

Spectral framework: With sufficient diffusion limitations, the least‐squares method suffers in general from significantly lower accuracy than the Galerkin, tau and orthogonal collocation methods. On the other hand, the least‐squares method with a direct minimization algorithm provides favourable lower system matrix condition numbers than the conventional least‐squares approach. Hence, for higher diffusion limitations, the least‐squares direct minimization formulation provides higher numerical accuracy than the conventional least‐squares method, but is still not as accurate as the Galerkin, tau and orthogonal collocation techniques. The accuracy of the least‐squares solution can compete with the other methods only in cases with low gradients in the solution.

Element framework: For a highly diffusion limited problem, the element framework is considered favourable as compared to the spectral framework. On the other hand, the element approach is not as efficient as the spectral solution for small Thiele modulus solutions.
Cell‐cell interactions mediate cytoskeleton organization and collective endothelial cell chemotaxis
Authors: Shamloo Amir
Published: July 2014

This study investigates the role of cell‐cell and cell‐ligand interactions in cytoskeleton organization of endothelial cells (ECs) and their directional migration within a microfluidic device. The migration of ECs in response to a biochemical factor was studied. Mathematical analysis of the cell migration pathways and cellular cytoskeleton revealed that directional migration, migration persistence length, migration speed, and cytoskeletal stress fiber alignment can be mediated by the level of cell contacts as well as the presence or absence of a biochemical polarizing factor. It was shown that in the presence of a biochemical polarizing factor, higher cell density and more frequent cell contacts has a reinforcing effect on collective cell chemotaxis. In contrast, in the absence of a polarizing factor, high cell density can decrease or suppress the ability of the cells to migrate. Also, the correlation of actin stress fiber organization and alignment with directional migration of ECs was investigated. It was shown that in the presence of a biochemical polarizing factor, stress fibers within the cytoskeleton of ECs can be significantly aligned parallel to the gradient direction when the cells have higher level of contacts. The results also show that the organization and alignment of actin stress fibers is mediated by cell adhesion junctions during collective cell migration and introduce cell‐cell interactions as a key factor during collective cell chemotaxis. © 2014 Wiley Periodicals, Inc.
Singly Modified Amikacin and Tobramycin Derivatives Show Increased rRNA A‐Site Binding and Higher Potency against Resistant Bacteria
Authors: Fair Richard J. , McCoy Lisa S. , Hensler Mary E. , Aguilar Bernice , Nizet Victor , Tor Yitzhak
Published: July 2014

Semisynthetic derivatives of the clinically useful aminoglycosides tobramycin and amikacin were prepared by selectively modifying their 6′′ positions with a variety of hydrogen bond donors and acceptors. Their binding to the rRNA A‐site was probed using an in vitro FRET‐based assay, and their antibacterial activities against several resistant strains (e.g., Pseudomonas aeruginosa, Klebsiella pneumonia, MRSA) were quantified by determining minimum inhibitory concentrations (MICs). The most potent derivatives were evaluated for their eukaryotic cytotoxicity. Most analogues displayed higher affinity for the bacterial A‐site than the parent compounds. Although most tobramycin analogues exhibited no improvement in antibacterial activity, several amikacin analogues showed potent and broad‐spectrum antibacterial activity against resistant bacteria. Derivatives tested for eukaryotic cytotoxicity exhibited minimal toxicity, similar to the parent compounds.
The role of SOX11 immunostaining in confirming the diagnosis of mantle cell lymphoma on fine‐needle aspiration samples
Authors: Zhang Y. Helen , Liu Joe , Dawlett Marilyn , Guo Ming , Sun Xiaoping , Gong Yun
Published: July 2014

BACKGROUND

Mantle cell lymphoma (MCL) demonstrates cytologic features that overlap with those of other types of B‐cell non‐Hodgkin lymphomas (B‐cell NHLs) containing small to medium‐sized cells. The accurate diagnosis of MCL is important because MCL has relatively more aggressive biologic behavior and thus requires specific treatment regimens. Fine‐needle aspiration (FNA) is used for diagnosing or staging lymphoma, often with the help of immunophenotyping by flow cytometry. However, the cellularity of an FNA sample may not be high enough for flow cytometry, leading to diagnostic difficulty. SOX11 immunostaining is helpful in the diagnosis of MCL in histologic sections. However, to the authors' knowledge, its diagnostic value for FNA samples has not been studied to date.

METHODS

Immunostains for SOX11 were performed on 69 FNA cases with final diagnoses of MCL (13 cases, including 10 classic type and 3 blastoid variant), marginal zone lymphoma (8 cases), follicular lymphoma (10 cases), small lymphocytic lymphoma (12 cases), Burkitt lymphoma (9 cases), plasma cell myeloma (7 cases), and benign lymph nodes (10 cases). Preparation types included cytospin slides (65 cases), direct smears (2 cases), and cell block sections (2 cases). The percentage of positive cells (defined as nuclear staining) and staining intensity were recorded.

RESULTS

All 13 cases of MCL were positive for SOX11 staining, with 12 cases demonstrating diffuse positivity. All other types of B‐cell NHL cases, plasma cell myelomas, and benign lymph nodes were found to have negative results. Weak staining was found in 1 MCL case of blastoid variant.

CONCLUSIONS

SOX11 immunostaining on FNA samples is highly sensitive and specific for MCL and can be used as a reliable adjunct to confirm MCL, especially in a recurrent setting. Cancer (Cancer Cytopathol) 2014;122:892–897. © 2014 American Cancer Society.