bluuebunny/crossref_metadata_2025 huggingface dataset:
Extended Lifetimes of Gold(III) Chloride Catalysts using Copper(II) Chloride and 2,2,6,6‐Tetramethylpiperidine 1‐Oxyl (TEMPO)
Authors: Graf Tyler A. , Anderson Thomas K. , Bowden Ned B.
Published: April 2011

The turnovers of a gold(III) chloride catalyst were increased by 3,300% with the addition of several equivalents of 2,2,6,6‐tetramethylpiperidine 1‐oxyl (TEMPO) and catalytic amounts of copper(II) chloride. A three‐component coupling reaction between piperidine, phenylacetylene, and benzaldehyde yielded a propargylic amine in quantitative conversions and isolated yields when gold(III) chloride was added in catalytic amounts, but the gold catalyst decomposed and had little to no reactivity when a second set of piperidine, phenylacetylene, and benzaldehyde was added after the reaction was complete. Thus, only one cycle was possible with gold(III) chloride. The addition of TEMPO and copper(II) chloride to reactions with gold(III) chloride maintained the catalytic activity of gold for up to 33 cycles. This result demonstrates a new way to greatly increase the turnovers of a gold(III) chloride catalyst with the addition of inexpensive, commercially available reagents.
Tandem Catalysis: Alcohol Oxidation and CC Bond Formation via CH Bond Activation
Authors: Simon Marc‐Olivier , Ung Gaël , Darses Sylvain
Published: April 2011

A tandem process involving oxidation of a benzylic alcohol functionality followed by hydroarylation is described. These two atom‐economic sequences are very convenient to access functionalized aromatic ketones, using simple ruthenium trichloride as catalyst precursor. Moreover they appear to be highly compatible, tolerant, and selective toward various functional groups, and the ease of the protocol should make it very convenient for synthetic purposes.
A New Class of Enantioselective Catalytic 2‐Pyrone Diels–Alder Cycloadditions
Authors: Wu Wanqing , Min Long , Zhu Lizhi , Lee Chi‐Sing
Published: April 2011

A highly enantioselective catalytic Diels–Alder (DA) cycloaddition of 2H‐pyran‐2,5‐diones (synthon of 5‐hydroxy‐2‐pyrones) has been developed with a Cinchona‐derived thiourea as the catalyst. The conditions were optimized by using 0.2 equiv. of the catalyst and 0.1 equiv. of formic acid in 2‐propanol at room temperature, which afforded the DA products in yields of up to 90% (exo/endo=5.5:1, 98% ee) with trans‐β‐nitrostyrene derivatives as the dienophiles. The structure/activity relationships of the bifunctional catalyst and the effects of the steric, electronic and hydrogen‐bonding properties of the dienophiles have been studied.
Fully Enzymatic N→C‐Directed Peptide Synthesis Using C‐Terminal Peptide α‐Carboxamide to Ester Interconversion
Authors: Nuijens Timo , Piva Elena , Kruijtzer John A. W. , Rijkers Dirk T. S. , Liskamp Rob M. J. , Quaedflieg Peter J. L. M.
Published: April 2011

Chemoenzymatic peptide synthesis is potentially the most cost‐efficient technology for the synthesis of short and medium‐sized peptides with some important advantages. For instance, stoichiometric amounts of expensive coupling reagents are not required and racemisation does not occur rendering purification easier compared to chemical peptide synthesis. In this paper, a novel interconversion reaction of peptide C‐terminal α‐carboxamides into primary alkyl esters with alcalase was used to develop a fully enzymatic peptide synthesis strategy. For each elongation step a cost‐efficient amino acid carboxamide building block was used followed by the interconversion of the elongated peptide carboxamide to the corresponding primary alkyl ester. These peptide esters are the starting materials for the next enzymatic peptide elongation step.
Stereo‐Controlled Asymmetric Bioreduction of α,β‐Dehydroamino Acid Derivatives
Authors: Stueckler Clemens , Winkler Christoph K. , Hall Mélanie , Hauer Bernhard , Bonnekessel Melanie , Zangger Klaus , Faber Kurt
Published: April 2011

α,β‐Dehydroamino acid derivatives proved to be a novel substrate class for ene‐reductases from the ‘old yellow enzyme’ (OYE) family. Whereas N‐acylamino substituents were tolerated in the α‐position, β‐analogues were generally unreactive. For aspartic acid derivatives, the stereochemical outcome of the bioreduction using OYE3 could be controlled by variation of the N‐acyl protective group to furnish the corresponding (S)‐ or (R)‐amino acid derivatives. This switch of stereopreference was explained by a change in the substrate binding, by exchange of the activating ester group, which was proven by 2H‐labelling experiments.
ASTRO‐FOLD 2.0: An enhanced framework for protein structure prediction
Authors: Subramani A. , Wei Y. , Floudas C. A.
Published: April 2011

The three‐dimensional (3‐D) structure prediction of proteins, given their amino acid sequence, is addressed using the first principles–based approach ASTRO‐FOLD 2.0. The key features presented are: (1) Secondary structure prediction using a novel optimization‐based consensus approach, (2) β‐sheet topology prediction using mixed‐integer linear optimization (MILP), (3) Residue‐to‐residue contact prediction using a high‐resolution distance‐dependent force field and MILP formulation, (4) Tight dihedral angle and distance bound generation for loop residues using dihedral angle clustering and non‐linear optimization (NLP), (5) 3‐D structure prediction using deterministic global optimization, stochastic conformational space annealing, and the full‐atomistic ECEPP/3 potential, (6) Near‐native structure selection using a traveling salesman problem‐based clustering approach, ICON, and (7) Improved bound generation using chemical shifts of subsets of heavy atoms, generated by SPARTA and CS23D. Computational results of ASTRO‐FOLD 2.0 on 47 blind targets of the recently concluded CASP9 experiment are presented. © 2011 American Institute of Chemical Engineers AIChE J, 2012
Process intensification of catalytic hydrogenation of ethylanthraquinone with gas‐liquid microdispersion
Authors: Tan J. , Zhang J. S. , Lu Y. C. , Xu J. H. , Luo G. S.
Published: April 2011

In this article, to miniaturize the hydrogenation reactor and make the H2O2 production with more safety a gas‐liquid microdispersion system was generated to intensify the process of catalytic hydrogenation of ethylanthraquinone by passing the gas‐liquid microdispersion system through a generally packed bed reactor. A microdispersion device with a 5 μm pore size microfiltration membrane as the dispersion medium has been developed and microbubbles in the size of 10–100 μm were successfully generated. The reaction and mass transfer performance was evaluated. The conversion of ethylanthraquinone as much as 35% was realized in less than 3.5 s. The overall volume mass transfer coefficient in the microdispersion reaction system reached in the range of 1–21 s−1, more than two orders of magnitude larger than the values in normal gas‐liquid trickle‐bed reactors. A mathematical model in the form of Sh = 2.0 + 54.7Sc1/3We1/2ϕ1/10 has been firstly suggested, which can well predict the overall mass transfer coefficient. © 2011 American Institute of Chemical Engineers AIChE J, 2012
Improved function of prototype 4.3‐mm Medtronic Quadcut microdebrider blade over standard 4.0‐mm Medtronic Tricut microdebrider blade
Authors: Boone John L. , Feldt Brent A. , McMains Kevin C. , Weitzel Erik K.
Published: April 2011

Objective

Test performance of a new prototype microdebrider blade. The commercially‐available, standard 4.0‐mm Medtronic straight Tricut blade was tested against the new, prototype 4.3‐mm Medtronic straight Quadcut blade in experimental surgical conditions utilizing both a nasal polyp (NP) analog (raw oysters) and an allergic fungal sinusitis (AFS) analog (minced beef cat food).

Methods

Both sides of 5 thawed, fresh‐frozen cadaver heads were utilized for NP analog removal. AFS analog was removed out of specimen containers. A total of 10 paired data points were collected for time of surgical removal and number of clogs comparing the 2 blades.

Results

For simulated AFS debris, the prototype clogged less than the standard blade (0 vs 4.5, p < 0.0001). There were no clogs noted for either blade with the NP analog. Time for debris eradication was significantly improved for both AFS analog (147.4 vs 262.0 seconds, p < 0.0001) and NP analog (43.7 vs 112.1 seconds, p < 0.0001).

Conclusion

The prototype blade offers faster debris and polyp removal and clogs less in the setting of allergic fungal debris. As the new blade is faster and more aggressive, introduction into a surgical setting should be guarded with an appropriate degree of caution. © 2011 ARS‐AAOA, LLC.
Comparative analysis of cost of endoscopic endonasal minimally invasive and sublabial‐transseptal approaches to the pituitary
Authors: Oosmanally Nadine , Paul John E. , Zanation Adam M. , Ewend Matthew G. , Senior Brent  A. , Ebert Charles S.
Published: April 2011

Background

Two surgical approaches to the pituitary are commonly used: the sublabial‐transseptal (SLTS) approach using microscopy and the endonasal endoscopic minimally invasive (MIPS) approach. Although outcomes are similar for both procedures, MIPS has become increasingly prevalent over the last 15 years. Limited cost analysis data comparing the 2 alternatives are available.

Methods

A retrospective analysis of cost and volume data was performed using data from the published literature and University of North Carolina at Chapel Hill (UNC) Hospitals. A sensitivity analysis of the parameters was used to evaluate the uncertainty in parameter estimates.

Results

The total cost in real dollars ranges from $11,438 to $12,513 and $18,095 to $21,005 per patient per procedure for MIPS and SLTS, respectively, with a cost difference ranging between $5582 and $9567 per patient per procedure. The sensitivity analysis indicates that the total cost for MIPS is most sensitive to: (1) average length of stay, (2) nursing costs, and (3) number of total complications, whereas the total cost for SLTS is most sensitive to: (1) average length of stay, (2) nursing cost, and (3) operating time. MIPS is less costly than SLTS between 94% and 98% of the time.

Conclusion

The results indicate that MIPS is less costly than SLTS at a large academic center. Future research should compare the outcomes and quality of life (QoL) associated with the 2 surgeries to improve the data used to determine the cost‐effectiveness of MIPS compared to SLTS. © 2011 ARS‐AAOA, LLC.
Variability of radiation exposure with in‐office sinus computed tomography examinations
Authors: Stewart Alexander E. , Stalp John T. , Futerman Cheryl , Vaughan Winston C.
Published: April 2011

Background

An increasing number of patients seeking care by an otolaryngologist are undergoing computed tomography (CT) examinations via in‐office CT scanners. Many otolaryngologists and patients are not fully aware of the radiation dosages and the associated risks. A recent study of common CT examinations demonstrated significant variability in radiation dosages for similar studies. Despite the relatively low doses associated with sinus scans, widely publicized studies and events have generated a renewal of physician, public, and regulatory agency awareness and concern regarding medical radiation exposure.

Methods

Phantom measurements and/or radiation dosage reports from CT scanners utilized by a large otolaryngology group in California were reviewed and compared. Different types of CT scanners from multiple manufacturers were included.

Results

There was nearly a 10‐fold difference (0.15–1.45 mSv) in radiation between scans obtained from in‐office, hospital‐based, and outpatient imaging facility CT scanners.

Conclusion

Significant relative variability can exist in radiation dosages associated with routine sinus CT scans obtained in different locations. There is a need for increased awareness and understanding among otolaryngologists and their patients regarding medical radiation exposure. All otolaryngologists should constantly consider the principle of “as low as reasonably achievable” (ALARA). Shielding, pediatric protocols, and other dosage reduction measures should be utilized whenever possible. © 2011 ARS‐AAOA, LLC.
Office‐based sclerotherapy for recurrent epistaxis due to hereditary hemorrhagic telangiectasia: a pilot study
Authors: Boyer Holly , Fernandes Patricia , Duran Olga , Hunter David , Goding George
Published: April 2011

Background

The aim of this pilot study is to evaluate office‐based sclerotherapy using sodium tetradecyl sulfate (STS) for epistaxis due to hereditary hemorrhagic telangiectasias (HHT). Patients with HHT suffer from unpredictable, recurrent, severe nasal bleeding necessitating emergency care, nasal packing, blood transfusions, and invasive procedures.

Methods

In this retrospective study 7 patients with a history of treatment for recurrent epistaxis due to HHT were treated in an office‐based setting with intralesional injection of STS. Treatment results were evaluated using a questionnaire. All patients had undergone multiple prior procedures attempting to control epistaxis.

Results

Patients had an average of 5 sclerotherapy treatments for HHT. Patients were treated using topical and/or local anesthesia with no reports of discomfort. Bleeding requiring intervention did not occur during the procedures. After the procedure all patients (100%) reported significantly less frequent and less severe nasal bleeding. A total of 83% reported that their need for nasal packing was reduced. All patients were willing to undergo the same treatment again. No complications such as perforation, crusting, or foul smell were reported.

Conclusion

This is the first clinical experience demonstrating that office‐based sclerotherapy with STS is a safe, tolerable, and useful alternative for the treatment of epistaxis due to HHT. © 2011 ARS‐AAOA, LLC.
Sites of attachment of Schneiderian papilloma: a retrospective analysis
Authors: Schneyer Mark S. , Milam Ben M. , Payne Spencer C.
Published: April 2011

Background

Inverted papilloma is a benign sinonasal tumor that arises from a localized attachment site. These attachment sites, however, have not been fully characterized in the literature. The objective of this research was to determine the specific distribution of attachment sites in patients with sinonasal papilloma.

Methods

Retrospective analysis of adult patients with sinonasal papilloma presenting to the University of Virginia between 1999 and 2010. These patients were reviewed and compared to historical controls with regard to histologic subtype and pedicle attachment site.

Results

A total of 83 patients were identified with 90 sites of attachment. For inverted/cylindrical papilloma, sites of attachment included the maxillary sinus (42%), ethmoid sinus (18%), nasal cavity (15%), middle/superior turbinate (12%), frontal sinus (10%), sphenoid sinus (1.5%), and cribriform plate (1.5%). Specific attachment sites within each group were identified, including 5 at the infraorbital nerve. The distribution of attachment sites differed significantly from historical controls resected via an open approach (p = 0.001), but did not differ significantly from historical controls endoscopically resected (p = 0.696). A comparison of more specific sites of attachments could not be performed due to the lack of this information in the literature.

Conclusion

The distribution of attachment sites in patients with sinonasal papilloma has changed as the endoscope has enabled more detailed identification of pedicle attachment, which has implications for management. © 2011 ARS‐AAOA, LLC.
Aromatic Rings in Chemical and Biological Recognition: Energetics and Structures
Authors: Salonen Laura M. , Ellermann Manuel , Diederich François
Published: April 2011

This review describes a multidimensional treatment of molecular recognition phenomena involving aromatic rings in chemical and biological systems. It summarizes new results reported since the appearance of an earlier review in 2003 in host–guest chemistry, biological affinity assays and biostructural analysis, data base mining in the Cambridge Structural Database (CSD) and the Protein Data Bank (PDB), and advanced computational studies. Topics addressed are arene–arene, perfluoroarene–arene, S⋅⋅⋅aromatic, cation–π, and anion–π interactions, as well as hydrogen bonding to π systems. The generated knowledge benefits, in particular, structure‐based hit‐to‐lead development and lead optimization both in the pharmaceutical and in the crop protection industry. It equally facilitates the development of new advanced materials and supramolecular systems, and should inspire further utilization of interactions with aromatic rings to control the stereochemical outcome of synthetic transformations.
Three‐Dimensional Structure of the Nasal Passageway of a Hagfish and its Implications for Olfaction
Authors: Holmes William M. , Cotton Ross , Xuan Viet Bui , Rygg Alex D. , Craven Brent A. , Abel Richard L. , Slack Robert , Cox Jonathan P.L.
Published: April 2011

From high‐resolution (65 μm) data acquired by magnetic resonance imaging, we have reconstructed the nasal passageway of a single adult hagfish specimen (probablyEptatretus stoutii). We have used this reconstruction to investigate how the anatomy and morphometry of the nasal passageway influence the olfactory ability of the hagfish. We found that the long, broad section of the passageway preceding the nasal chamber will delay the response to an odor by 1–2 s. Diffusion of odorant to the olfactory epithelium, on which the olfactory sensitivity of an animal depends, will be favored by the relatively large surface area of the olfactory epithelium (∼140 mm2) and a modest expansion in the nasal chamber. Oscillating flow (0.3–0.4 Hz) within the narrow (65–130 μm) sensory channels of the nasal chamber is laminar (Reynolds number ∼ 5) and quasi‐steady (Womersley number generally less than one). Distribution of flow over the olfactory epithelium may be aided by: (a) a narrowing before the nasal chamber; (b) partial blockage of the nasal passageway by a protrusion on the central olfactory lamella; and (c) the inward inclination of the olfactory lamellae. Anat Rec,, 2011. © 2011 Wiley‐Liss, Inc.
5‐Nitro‐2‐(3‐Phenylpropylamino) Benzoic Acid Induced Drug Resistance to Cisplatin in Human Erythroleukemia Cell Lines
Authors: Xu Ye , Zheng Hua , Kang Jin‐Song , Zhang Lei , Su Jing , Li Hong‐Yan , Sun Lian‐Kun
Published: April 2011

Mechanisms of cisplatin resistance in cancer cells are not fully understood. Here, we showed a critical role for the chloride channel‐3 (ClC‐3) in cisplatin resistance in human erythroleukemia K562 and RK562 cells. We found that a chloride channel blocker 5‐nitro‐2‐(3‐phenylpropylamino) benzoic acid (NPPB) could protect cells from cisplatin‐induced apoptosis. NPPB treatment decreased the mRNA and the protein expression of Bax/Bcl‐2, decreased the protein expressions of cytochrome C and caspase‐3, and increased the mRNA expressions of cyclin D1 and ClC‐3 in cells treated with cisplatin. The caspase‐3 activity was decreased significantly and the rate of cell apoptosis was decreased. NPPB treatment increased CIC‐3 expression, which could increase acidification of intracellular compartments, and increased sequestration of cisplatin, inducing decreased effective drug concentrations, and subsequently cell death. Collectively, our data indicate that NPPB can induce drug resistance to cisplatin by upregulating the expression of CIC‐3. NPPB‐induced CIC‐3 expression facilitates acidification of sequestrated cisplatin, and plays an important role in preventing cisplatin‐induced apoptosis in human erythroleukemia K562 and RK562 cells. Anat Rec,, 2011. © 2011 Wiley‐Liss, Inc.
Monosodium urate monohydrate crystal–recruited noninflammatory monocytes differentiate into M1‐like proinflammatory macrophages in a peritoneal murine model of gout
Authors: Martin William John , Shaw Odette , Liu Xiao , Steiger Stefanie , Harper Jacquie L.
Published: April 2011

Objective

To profile monosodium urate monohydrate (MSU) crystal–recruited monocyte inflammatory function during the course of in vivo differentiation, in a murine model of peritoneal MSU crystal–induced inflammation.

Methods

C57BL/6J mice were injected intraperitoneally with MSU crystals, and the peritoneal cells were harvested at different time points. The MSU crystal–recruited monocyte/macrophage population was analyzed for the expression of differentiation and activation markers, cytokine production following MSU crystal restimulation ex vivo and in vivo, expression of NLRP3‐associated proteins (ASC, caspase 1) and pro–interleukin‐1β (proIL‐1β), and phagocytic capacity.

Results

Monocytes recruited 8 hours after MSU crystal stimulation (F4/80lowGr‐1int7/4+) exhibited poor phagocytic capacity, expressed low levels of proIL‐1β, and failed to produce proinflammatory cytokines in response to MSU crystal restimulation. In the absence of MSU crystal restimulation, differentiating monocytes produced low levels of transforming growth factor β1 ex vivo, and this was abrogated following MSU crystal restimulation. Over time these cells developed a proinflammatory phenotype in vivo, characterized by the production of IL‐1β, tumor necrosis factor α, IL‐6, CCL2 (monocyte chemotactic protein 1), and CXCL1 (cytokine‐induced neutrophil chemoattractant) following ex vivo MSU crystal restimulation, and leading to IL‐1β production and cell infiltration following MSU crystal rechallenge in vivo. Proinflammatory function was associated with differentiation toward a macrophage phenotype (F4/80highGr‐1–7/4–), an increase in phagocytic capacity, and an increase in the expression of proIL‐1β.

Conclusion

MSU crystal–recruited monocytes differentiate into proinflammatory M1‐like macrophages in vivo. This proinflammatory macrophage phenotype is likely to play a key role in perpetuating inflammation in gouty arthritis in the presence of ongoing deposition of fresh MSU crystals.
Systemic sclerosis is an independent risk factor for increased coronary artery calcium deposition
Authors: Mok Mo Yin , Lau Chak Sing , Chiu Sonny Sau Hin , Tso Annette Wai Kwan , Lo Yi , Law Lawrence Siu Chun , Mak Ka Fung , Wong Woon Sing , Khong Peh Lan , Lam Karen Siu Ling
Published: April 2011

Objective

Endothelial dysfunction and inflammation are pathogenic mechanisms common to systemic sclerosis (SSc) and atherosclerosis. This study was undertaken to examine the relationship between coronary atherosclerosis, as assessed by the coronary artery calcium score (CACS), and conventional cardiovascular and disease‐specific risk factors in SSc patients.

Methods

The CACS was measured by computed tomography, and cardiovascular risk factors were examined in SSc patients and compared with controls matched for age, sex, and glycemic status. Disease activity score, antiphospholipid antibodies, high‐sensitivity C‐reactive protein level, and erythrocyte sedimentation rate were measured in SSc patients. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were determined.

Results

We recruited 53 SSc patients (50 women and 3 men) and 106 controls. The patients had a mean ± SD age of 53.1 ± 12.9 years and a median disease duration of 9 years. Compared to controls, SSc patients had significantly lower low‐density lipoprotein (LDL) cholesterol levels (P = 0.001), high‐density lipoprotein cholesterol levels (P = 0.01), diastolic blood pressure, waist circumference, and body mass index and were more likely to be receiving vasodilators (all P < 0.001). There was a significantly higher proportion of SSc patients among subjects with more severe coronary calcification (CACS ≥101) compared to those with lesser severity (CACS <100) (56.5% versus 29.4%; P = 0.01). Multiple logistic regression analysis revealed SSc to be an independent determinant for a CACS ≥101 (OR 10.89 [95% CI 2.21–53.75], P = 0.003) together with age and LDL cholesterol level after adjustment for other cardiovascular risk factors. Among disease‐specific factors, only disease duration (OR 1.14 [95% CI 1.02–1.27], P = 0.02) was independently associated with more severe coronary calcification (CACS ≥101).

Conclusion

Our findings indicate that SSc is an independent risk factor for coronary calcification, in addition to the conventional risk factors for coronary atherosclerosis, such as age and hypertension.
Increased inflammatory cytokine expression in the vastus lateralis of patients with knee osteoarthritis
Authors: Levinger Itamar , Levinger Pazit , Trenerry Marissa K. , Feller Julian A. , Bartlett John R. , Bergman Neil , McKenna Michael J. , Cameron‐Smith David
Published: April 2011

Objective

Increased inflammation and pain are inseparable parts of knee osteoarthritis (OA) that may lead to disuse of the affected limb. The aim of this study was to examine the effects of knee OA on inflammation‐ and atrophy‐related genes and proteins in the vastus lateralis muscle of patients with knee OA.

Methods

Nineteen patients with knee OA and 14 asymptomatic control subjects matched for age and body mass index underwent strength measurements and a muscle biopsy. Muscle was analyzed for the total cellular protein of inflammatory kinases (p65 NF‐κB, JNK1/2, STAT‐3, and suppressor of cytokine signaling 3 [SOCS‐3]) and inflammatory intracellular molecules (interleukin‐6 [IL‐6], IL‐8, monocyte chemoattractant protein 1 [MCP‐1], tumor necrosis factor α [TNFα], IL‐1β, and atrogin‐1).

Results

Knee OA resulted in greater levels of IL‐6 protein (34%; P = 0.002). The levels of inflammatory kinases, including STAT‐3 (187%; P = 0.002), p65 NF‐κB (156%; P = 0.002), and JNK1 (179%; P = 0.027), were also elevated. Furthermore, elevated expression of gene transcripts encoding MCP‐1 (28%; P = 0.023), TNFα (85%; P < 0.001), and SOCS‐3 (38%; P = 0.055) was observed in patients with knee OA compared with control subjects. Patients with knee OA had reduced muscle strength compared with control subjects (mean ± SEM 84.7 ± 8.7 versus 143.1 ± 20.8 Nm; P = 0.005). Negative correlations were observed between muscle strength and MCP‐1 protein abundance (r = −0.37 [P = 0.042]) and the gene expression of TNFα and atrogin‐1 messenger RNA (r = −0.46 [P = 0.012] and r = −0.36 [P = 0.040], respectively).

Conclusion

Gene expression and the protein abundance of numerous muscle markers of inflammation and atrophy were elevated in patients with knee OA, and the increase in muscle inflammation was associated with a reduction in muscle strength. Given the role inflammation markers may play in muscle strength and atrophy, further studies are needed to investigate the effect of exercise intervention on skeletal muscle inflammation.
Nanoscale Effects on the Stability of the λ‐Ti3O5 Polymorph
Authors: Makiura Rie , Takabayashi Yasuhiro , Fitch Andrew N. , Tokoro Hiroko , Ohkoshi Shin‐ichi , Prassides Kosmas
Published: April 2011

The nanocrystalline valency‐delocalized λ‐phase of the binary oxide Ti3O5 has recently emerged as a promising phase‐change material that exhibits rapid photo‐reversible optical and resistance changes at ambient temperature. Nanoscaling caused the monoclinic‐λ to monoclinic charge‐ordered β‐phase structural instability to shift to considerably lower temperatures compared to the bulk material, and led to a broad thermal hysteresis. The structural transformation was accompanied by a large change in volume and large lattice relaxations, which imply the presence of strong electron–phonon coupling. We attribute the suppression of the phase transition to the enhanced surface energy on the nanoscale.
UV Photolysis of ClOOCl and the Ozone Hole
Authors: Lin Jim J. , Chen Andrew F , Lee Yuan T.
Published: April 2011

The photochemistry of the ClO dimer (ClOOCl) plays a central role in the catalytic destruction of polar stratospheric ozone. In spite of decades of intense investigations, some of its laboratory photochemical data had not reached the desired accuracy to allow a reliable simulation of the stratospheric ozone loss until recently. Inevitable impurities in ClOOCl samples have obstructed conventional measurements. In particular, an absorption measurement of ClOOCl in 2007, which gave much lower cross sections than previous studies, implied that the formation of the ozone hole cannot be explained with current chemical models. Scientists have wondered whether the model is insufficient or the data is erroneous. Efforts aiming to resolve this controversy are reviewed in this paper, which emphasizes newly developed experiments to determine two critical photochemical properties of ClOOCl—its absorption cross section and product branching ratio—including the first reported product branching ratio at 351.8 nm photolysis.
JSPS Asian Core Program: Cutting‐Edge Organic Chemistry in Asia and IUPAC Strategic Planning for a New East and Southeast Asian Network for Organic Chemistry
Authors: Nishida Atsushi , Uang Biing‐Jiun , Chittchang Montakarn , Isobe Minoru
Published: April 2011

JSPS Asian Core Program: Cutting‐Edge Organic Chemistry in Asia and IUPAC Strategic Planning for a New East and Southeast Asian Network for Organic Chemistry.
Hard and soft spectral states of ULXs
Authors: Soria R.
Published: April 2011

I discuss some differences between the observed spectral states of ultraluminous X‐ray sources (ULXs) and the canonical scheme of spectral states defined in Galactic black holes. The standard interpretation of ULXs with a curved spectrum, or a moderately steep power‐law with soft excess and high‐energy downturn, is that they are an extension of the very high state, up to luminosities ≈1–3LEdd. Two competing models are Comptonization in a warm corona, and slim disk; I suggest bulk motion Comptonization in the radiatively‐driven outflow as another possibility. The interpretation of ULXs with a hard power‐law spectrum is more problematic. Some of them remain in that state over a large range of luminosities; others switch directly to a curved state without going through a canonical high/soft state. I suggest that those ULXs are in a high/hard state not seen in Galactic black holes; that state may overlap with the low/hard state at lower accretion rates, and extend all the way to Eddington accretion rates. If some black holes can reach Eddington accretion rates without switching to a standard‐disk‐dominated state, it is also possible that they never quench their steady jets (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A large catalogue of ultraluminous X‐ray source candidates in nearby galaxies
Authors: Walton Dj. , Gladstone J.C. , Roberts T.P. , Fabian A.C.
Published: April 2011

Since their discovery, Ultraluminous X‐ray sources (ULXs) have attracted attention due to their combination of extreme luminosities and extra‐nuclear locations. However, they are a fairly rare phenomenon, and attempts to investigate the general properties of the population have been hindered by a relative lack of known sources. Here, we present a large catalogue of ULX candidates including 655 detections of 475 discrete sources, based on the 2XMM Serendipitous Survey. To demonstrate the potential of such a resource, we present some scientific analysis of this population, focusing on the spectral turnover seen, often at ∼6 keV, in the highest quality ULX data. We also demonstrate how the recent reflection and Comptonisation interpretations of this feature may be distinguished observationally in the future, specifically using NGC 4517 ULX1, a previously unanalysed source with high quality data, as an example case (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The population of ULXs in the spiral galaxy NGC 2276
Authors: Wolter A. , Pizzolato F. , Rota S. , Mapelli M. , Ripamonti E.
Published: April 2011

We present results for X‐ray point sources in the Sc galaxy NGC 2276, obtained by analyzing Chandra data. The galaxy is known to be very active in many wavelengths, possibly due to gravitational interaction with the central elliptical of the group, NGC 2300. However, previous XMM‐Newton observations resulted in the detection of only one bright ULX and extended hot gas emission. We present here the X‐ray population in NGC 2276 which comprises 17 sources. We found that 6 of them are new ULX sources in this spiral galaxy resolved for the first time by Chandra. We constructed the luminosity function that can be interpreted as mainly due of high mass X‐ray binaries, and estimate the star formation rate (SFR) to be SFR ∼5–10 M⊙ yr–1 (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The supergiant optical counterpart of ULX P13 in NGC 7793
Authors: Motch C. , Pakull M.W. , Grisé F. , Soria R.
Published: April 2011

We have identified the optical counterpart of the ULX source P13 in the nearby spiral galaxy NGC 7793. The object is a V ∼ 20.5 mag star, ten times brighter than any other established counterpart of a ULX in nearby galaxies. Medium resolution optical spectroscopy carried out in 2008 and 2009 with the ESO‐VLT reveals the presence of narrow high order Balmer, He I and Mg II absorption lines indicating a late B‐type supergiant companion star with mass between 10 and 20 M⊙. Stellar Hβ and He II λ 4686 Å emission lines are also seen superposed on the photospheric spectrum. We detect different patterns of radial velocity variations from the emission and absorption lines over a time interval of one month. The velocity of the high order Balmer absorption lines changes by ∼100 km s–1 while the Hβ and He II λ 4686 Å emission components vary by about the same amount but with a different phasing. Assuming that the observed velocity changes trace the motion of the mass‐donor star and of the X‐ray source implies a mass of the accreting black hole in the range of 3 to 100 M⊙ with a most probable value of ∼10 to 20 M⊙. We expect an orbital period in the range of 20 to 40 days based on the low density of the supergiant star. P13 is likely in a short‐lived, and thus rare high X‐ray luminosity evolutionary state associated with the ascension of the donor star onto the supergiant stage (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
New observations of ULX supershells, and their implications
Authors: Russell D.M. , Yang Y.‐J. , Gladstone J.C. , Wiersema K. , Roberts T.P.
Published: April 2011

New optical narrowband imaging observations of the fields of several ultra‐luminous X‐ray sources (ULXs) are presented. Known supershell nebulae are associated with a number of these ULXs, which we detect in emission lines filters such as [S II], He II, [O II] and [O III]. New nebulae are discovered, which are candidate ULX‐powered supershells. The morphologies and emission line fluxes of these nebulae could then be used to infer the properties of the emitting gas, which gives clues to the energizing source (photoionization and/or shock‐excitation, both possibly from the ULX). Studies of supershells powered by ULXs can help to constrain the nature of ULXs themselves, such as the isotropy of the X‐ray emission and the strength of their outflows (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Does NGC 5408 X‐1 really contain an intermediate‐mass black hole?
Authors: Middleton M.J. , Roberts T.P. , Done C. , Jackson F.E.
Published: April 2011

NGC,5408 X‐1 is one of only a handful of ultraluminous X‐ray sources (ULXs) to demonstrate a strong quasi‐periodic oscillation (QPO) in its lightcurve. This has been interpreted as being analogous to the type C low‐frequency QPO seen in black hole binaries (BHBs) when accreting at sub‐Eddington rates, implying an intermediate‐mass black hole (IMBH). However, in BHBs this QPO has a centroid frequency that scales tightly with the position of the low‐frequency break in the broad band power spectrum. In recent work we re‐assessed the data and found that the position of the break does not comply with the observed relationship in either of the available, archival XMM‐Newton observations. Thus the broad band power spectral shape does not support this identification of the QPO. We also found that the X‐ray spectra do not support a sub‐Eddington identification, instead favouring a two component model of soft thermal emission at low energies, together with low‐temperature, optically thick Comptonisation producing a tail which dominates above 2 keV. The energy dependent variability supports this deconvolution and indicates a large amount of variability present in the hard component. Such variability is only met by the BHB, GRS 1915+105, and some extreme NLS1s. This suggests that NGC 5408 X‐1 is in a similar super‐Eddington state, placing a natural limit on the mass of ≤100 M⊙. Here we compare in greater detail our analysis to that of previous work on this source's variability characteristics (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Exploring the nature of the brightest hyper‐luminous X‐ray source
Authors: Farrell S.A. , Servillat M. , Wiersema K. , Barret D. , Godet O. , Heywood I. , Maccarone T.J. , Oates S.R. , Plazolles B. , Webb N.A.
Published: April 2011

The small subset of hyper‐luminous X‐ray sources with luminosities in excess of ∼1041 erg s–1 are hard to explain without the presence of an intermediate mass black hole, as significantly super‐Eddington accretion and/or very small beaming angles are required. The recent discovery of HLX‐1, the most luminous object in this class with a record breaking luminosity of ∼1042 erg s–1 in the galaxy ESO 243‐49, therefore currently provides some of the strongest evidence for the existence of intermediate mass black holes. HLX‐1 is almost an order of magnitude brighter than the other hyperluminous sources, and appears to exhibit X‐ray spectral and flux variability similar to Galactic stellar mass black hole X‐ray binaries. In this paper we review the current state of knowledge on this intriguing source and outline the results of multi‐wavelength studies from radio to ultra‐violet wavelengths, including imaging and spectroscopy of the recently identified optical counterpart obtained with the Very Large Telescope. These results continue to support an intermediate mass black hole in excess of 500 M⊙ (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Remnants of massive metal‐poor stars: Viable engines for ultra‐luminous X‐ray sources
Authors: Mapelli M. , Ripamonti E. , Zampieri L. , Colpi M.
Published: April 2011

Massive metal‐poor stars might end their life by directly collapsing into massive (≈25–80 M⊙) black holes (BHs). We derive the number of massive BHs (N BH) that are expected to form per galaxy via this mechanism. We select a sample of 66 galaxies with X‐ray coverage, measurements of the star formation rate (SFR) and of the metallicity. We find that NBH correlates with the number of observed ultra‐luminous X‐ray sources (ULXs) per galaxy in this sample. We discuss the dependence of NULX and of NBH on the SFR and on the metallicity (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The metallicity of the nebula surrounding the ultra‐luminous X‐ray source NGC 1313 X‐2
Authors: Ripamonti E. , Mapelli M. , Zampieri L. , Colpi M.
Published: April 2011

Recent models of the formation of ultra‐luminous X‐ray sources (ULXs) predict that they preferentially form in low‐metallicity environments. We look at the metallicity of the nebula surrounding NGC 1313 X‐2, one of the best‐studied ULXs. Simple estimates, based on the extrapolation of the metallicity gradient within NGC 1313, or on empirical calibrations (relating metallicity to strong oxygen lines) suggest a quite low metal content (Z ∼ 0.1Z⊙). But such estimates do not account for the remarkably strong X‐ray flux irradiating the nebula. Then, we build photoionization models of the nebula using CLOUDY; using such models, the constraints on the metallicity weaken substantially, as we find 0.15Z⊙ ≤ Z ≤ 0.5Z⊙ (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Molecular and developmental mechanisms of congenital heart valve disease
Authors: Lincoln Joy , Yutzey Katherine E.
Published: April 2011

Congenital heart disease occurs in approximately 1% of all live births and includes structural abnormalities of the heart valves. However, this statistic underestimates congenital valve lesions, such as bicuspic aortic valve (BAV) and mitral valve prolapse (MVP), that typically become apparent later in life as progressive valve dysfunction and disease. At present, the standard treatment for valve disease is replacement, and approximately 95,000 surgical procedures are performed each year in the United States. The most common forms of congenital valve disease include abnormal valve cusp morphogenesis, as in the case of BAV, or defects in extracellular matrix (ECM) organization and homeostasis, as occurs in MVP. The etiology of these common valve diseases is largely unknown. However, the study of murine and avian model systems, along with human genetic linkage studies, have led to the identification of genes and regulatory processes that contribute to valve structural malformations and disease. This review focuses on the current understanding and therapeutic implications of molecular regulatory pathways that control valve development and contribute to valve disease. Birth Defects Research (Part A), 2011. © 2011 WileyA‐Liss, Inc.
Wnt signaling regulates atrioventricular canal formation upstream of BMP and Tbx2
Authors: Verhoeven Manon C. , Haase Christa , Christoffels Vincent M. , Weidinger Gilbert , Bakkers Jeroen
Published: April 2011

In the developing heart, the atrioventricular canal (AVC) is essential for separation and alignment of the cardiac chambers, for valve formation, and serves to delay the electrical impulse from the atria to the ventricles. Defects in various aspects of its formation are the most common form of congenital heart defects. Using mutant and transgenic approaches in zebrafish, this study demonstrates that Wnt/β‐catenin signaling is both sufficient and required for the induction of BMP4 and Tbx2b expression in the AVC and consequently the proper patterning of the myocardium. Furthermore, genetic analysis shows that Wnt/β‐catenin signaling is upstream and in a linear pathway with BMP and Tbx2 during AVC specification. Birth Defects Research(Part A), 2011. ©2011 Wiley‐Liss, Inc.
What chick and mouse models have taught us about the role of the endocardium in congenital heart disease
Authors: DeLaughter Daniel M. , Saint‐Jean Leshana , Baldwin H. Scott , Barnett Joey V.
Published: April 2011

Specific cell and tissue interactions drive the formation and function of the vertebrate cardiovascular system. Although much attention has been focused on the muscular components of the developing heart, the endocardium plays a key role in the formation of a functioning heart. Endocardial cells exhibit heterogeneity that allows them to participate in events such as the formation of the valves, septation of the outflow tract, and trabeculation. Here we review, the contributions of the endocardium to cardiovascular development and outline useful approaches developed in the chick and mouse that have revealed endocardial cell heterogeneity, the signaling molecules that direct endocardial cell behavior, and how these insights have contributed to our understanding of cardiovascular development and disease. Birth Defects Research (Part A), 2011. © 2011 Wiley‐Liss, Inc.
Genome‐wide approaches to the study of adaptive gene expression evolution
Authors: Fraser Hunter B.
Published: April 2011

The role of gene expression in evolutionary adaptation has been a subject of debate for over 40 years.cis‐regulation of transcription has been proposed to be the primary source of morphological novelty in evolution, though this is based on only a handful of examples. Recently the first genome‐wide studies of gene expression adaptation have been published, giving us an initial global view of this process. Systematic studies such as these will allow a number of key questions currently facing the field of gene expression evolution to be addressed.
Pairing phosphoinositides with calcium ions in endolysosomal dynamics
Authors: Shen Dongbiao , Wang Xiang , Xu Haoxing
Published: April 2011

The direction and specificity of endolysosomal membrane trafficking is tightly regulated by various cytosolic and membrane‐bound factors, including soluble NSF attachment protein receptors (SNAREs), Rab GTPases, and phosphoinositides. Another trafficking regulatory factor is juxta‐organellar Ca2+, which is hypothesized to be released from the lumen of endolysosomes and to be present at higher concentrations near fusion/fission sites. The recent identification and characterization of several Ca2+ channel proteins from endolysosomal membranes has provided a unique opportunity to examine the roles of Ca2+ and Ca2+ channels in the membrane trafficking of endolysosomes. SNAREs, Rab GTPases, and phosphoinositides have been reported to regulate plasma membrane ion channels, thereby suggesting that these trafficking regulators may also modulate endolysosomal dynamics by controlling Ca2+ flux across endolysosomal membranes. In this paper, we discuss the roles of phosphoinositides, Ca2+, and potential interactions between endolysosomal Ca2+ channels and phosphoinositides in endolysosomal dynamics.
Evaluation of microwave‐assisted extraction for aristolochic acid from Aristolochiae Fructus by chromatographic analysis coupled with nephrotoxicity studies
Authors: Zhou Ting , Xiao Xiao‐Hua , Wang Jia‐Yue , Chen Jin‐Ling , Xu Xian‐Fang , He Zhi‐Feng , Li Gong‐Ke
Published: April 2011

In this paper, a microwave‐assisted extraction (MAE) method was established for aristolochic acid‐I from Aristolochiae Fructus, and the advantage of MAE was evaluated by chromatographic analysis coupled with nephrotoxicity studies. The experimental parameters of MAE for aristolochic acid‐I in Aristolochiae Fructus were investigated and MAE was compared with Soxhlet extraction and ultrasound‐assisted extraction in terms of extraction yields and extraction conditions. Under the optimum conditions, MAE could provide higher extraction yields of aristolochic acid‐I (1.10 mg/g) than ultrasound‐assisted extraction (0.82 mg/g) and Soxhlet extraction (0.95 mg/g), in addition to using less solvent and having a shorter extraction time. Furthermore, the nephrotoxicities of the extracts of Aristolochiae Fructus from different extraction procedures were investigated in Sprague–Dawley rats. The results of nephrotoxicity studies of, for example, general conditions, biochemistry parameters and histopathology examination showed no significantly differences in the nephrotoxicity levels of the extracts from MAE and that from Soxhlet extraction. These results indicated that MAE technique is a simple, rapid and effective extraction method, and the microwave irradiation during MAE procedure did not have any influence on the nephrotoxicity of Aristolochiae Fructus compared with Soxhlet extraction. Copyright © 2011 John Wiley & Sons, Ltd.
HIVE: Helping interdisciplinary vocabulary engineering
Authors: Greenberg Jane , Losee Robert , Agüera José Ramón Pérez , Scherle Ryan , White Hollie , Willis Craig
Published: April 2011

Editor's Summary

HIVE (Helping Interdisciplinary Vocabulary Engineering) is an effort to automatically generate metadata for content, drawing descriptor terms from multiple vocabularies encoded as Simple Knowledge Organization Systems (SKOS). The effort is a response to the challenges of interoperability, cost and usability of multiple terminology sets often needed to adequately describe digital resources. By offering access to more than one vocabulary with useful descriptors for a broad domain, HIVE enables aggregating the best terms to describe resources and automatically apply metadata. HIVE offers knowledge management value for multidisciplinary digital collections while demonstrating the expanded potential use of SKOS. The initiative is headed by the Metadata Research Center at the University of North Carolina's School of Information and Library Science working with several institutional partners. Conferences and workshops are scheduled to inform interested developers and users, who are invited to try out, contribute to and evaluate the system.