bluuebunny/crossref_metadata_2025 huggingface dataset:
Neuroproteomic profiling of human brain tissue using multidimensional separation techniques and selective enrichment of membrane proteins
Authors: Musunuri Sravani , Shevchenko Ganna , Bergquist Jonas
Published: November 2012

Hydrophobic membrane proteins (MPs) occupy a unique niche in the brain proteome research due to their important physiological roles. Therefore, the extraction, separation, and identification of MPs are of great interest in proteomic analysis. We applied various proteomic techniques to enrich, separate, and analyze the human brain proteome, including membrane proteome. Temperature‐induced phase fractionation with the nonionic surfactant Triton X‐114 was used to simultaneously extract, separate, and concentrate low abundant hydrophobic and high abundant hydrophilic proteins from human brain tissue. The extracted and delipidated proteins were analyzed by two‐dimensional gel electrophoresis (2DE). Approximately 600 spots were detected in the gels. In‐solution digestion was performed on 3 kDa spin filters. Tryptic peptides were separated using RP nano‐LC and analyzed using two different high performance mass spectrometers, linear ion trap‐Fourier transform and a linear ion trap‐Orbitrap to reveal the low abundant MPs. In total, 837 and 780 unique proteins were identified by using linear ion trap‐Fourier transform and linear ion trap‐Orbitrap mass spectrometers, respectively. More than 29% of the identified proteins were classified as MPs with significant biological functions such as ion channels and transporters. Our study establishes a simple and rapid shotgun approach for the characterization of the brain proteome, and allows comprehensive analysis of brain membrane proteomes.
Micellar ordered structure effects on high‐resolution CE‐SSCP using Pluronic triblock copolymer blends
Authors: Hwang Hee Sung , Shin Gi Won , Park Han Jin , Ryu Chang Yeol , Jung Gyoo Yeol
Published: November 2012

Pluronic F108 block copolymers have shown a great promise to achieve the desirable high resolution in the conformation‐sensitive separation of ssDNA using CE‐SSCP. However, fundamental understanding of the structures and properties of Pluronic matrix affecting the resolution is still limited. Unlike conventional gel‐forming homopolymers, Pluronic F108 block copolymers are amphiphilic macromolecules consisting of poly(ethylene oxide)‐b‐poly(propylene oxide)‐b‐poly(ethylene oxide) triblock copolymers, which are capable of forming a highly ordered micellar structure in aqueous solution. In this study, we have performed a series of experiments by blending different types of Pluronic polymers to control the formation of micelles and to study the correlation between separation and rheological characteristics of Pluronic gels affecting the resolution of CE‐SSCP. Our experiments have been specifically designed to elucidate how the micellar structure affects the resolution of CE‐SSCP upon altering the size uniformity and constituent homogeneity of the micelles. Our results suggest that uniformly sized micelle packing is the primary structural feature of Pluronic gel matrix for the high‐resolution separation, while the size and constituent of the micelle themselves need to be considered as secondary factors.
The exposure of autoantigens by microparticles underlies the formation of potent inflammatory components: the microparticle‐associated immune complexes
Authors: Cloutier Nathalie , Tan Sisareuth , Boudreau Luc H. , Cramb Catriona , Subbaiah Roopashree , Lahey Lauren , Albert Alexandra , Shnayder Ruslan , Gobezie Reuben , Nigrovic Peter A. , Farndale Richard W. , Robinson William H. , Brisson Alain , Lee David M. , Boilard Eric
Published: November 2012

Immunoglobulins, antigens and complement can assemble to form immune complexes (IC). ICs can be detrimental as they propagate inflammation in autoimmune diseases. Like ICs, submicron extracellular vesicles termed microparticles (MP) are present in the synovial fluid from patients affected with autoimmune arthritis. We examined MPs in rheumatoid arthritis (RA) using high sensitivity flow cytometry and electron microscopy. We find that the MPs in RA synovial fluid are highly heterogeneous in size. The observed larger MPs were in fact MP‐containing ICs (mpICs) and account for the majority of the detectable ICs. These mpICs frequently express the integrin CD41, consistent with platelet origin. Despite expression of the Fc receptor FcγRIIa by platelet‐derived MPs, we find that the mpICs form independently of this receptor. Rather, mpICs display autoantigens vimentin and fibrinogen, and recognition of these targets by anti‐citrullinated peptide antibodies contributes to the production of mpICs. Functionally, platelet mpICs are highly pro‐inflammatory, eliciting leukotriene production by neutrophils. Taken together, our data suggest a unique role for platelet MPs as autoantigen‐expressing elements capable of perpetuating formation of inflammatory ICs.
Incorporating Network Structure in Integrative Analysis of Cancer Prognosis Data
Authors: Liu Jin , Huang Jian , Ma Shuangge
Published: November 2012

In high‐throughput cancer genomic studies, markers identified from the analysis of single datasets may have unsatisfactory properties because of low sample sizes. Integrative analysis pools and analyzes raw data from multiple studies, and can effectively increase sample size and lead to improved marker identification results. In this study, we consider the integrative analysis of multiple high‐throughput cancer prognosis studies. In the existing integrative analysis studies, the interplay among genes, which can be described using the network structure, has not been effectively accounted for. In network analysis, tightly connected nodes (genes) are more likely to have related biological functions and similar regression coefficients. The goal of this study is to develop an analysis approach that can incorporate the gene network structure in integrative analysis. To this end, we adopt an AFT (accelerated failure time) model to describe survival. A weighted least squares approach, which has low computational cost, is adopted for estimation. For marker selection, we propose a new penalization approach. The proposed penalty is composed of two parts. The first part is a group MCP penalty, and conducts gene selection. The second part is a Laplacian penalty, and smoothes the differences of coefficients for tightly connected genes. A group coordinate descent approach is developed to compute the proposed estimate. Simulation study shows satisfactory performance of the proposed approach when there exist moderate‐to‐strong correlations among genes. We analyze three lung cancer prognosis datasets, and demonstrate that incorporating the network structure can lead to the identification of important genes and improved prediction performance.
A One‐Pot Organometallic Route from a 4‐Alkenylpyridine to a 4,4‐Spiro‐Linked Ethyl 1,4‐Dihydropyridine‐1‐carboxylate
Authors: Fraenkel Gideon , Chow Albert , Liang Yulan , Song Jinhua , Gallucci Judith
Published: November 2012

In a one‐pot process without isolation of intermediates, (but‐3‐en‐1‐yl)pyridine (13) is treated sequentially with dicyclohexylborane, trimethylaluminium, and ethyl carbonochloridate yielding ethyl 1,4‐dihydro‐4,4‐(tetramethylene)pyridine‐1‐carboxylate (=ethyl 8‐azaspiro[4.5]deca‐6,9‐diene‐8‐carboxylate; 2) in 46% yield based on starting alkenylpyridine 13 (Scheme 5).
Syntheses of Racemic and Scalemic cis‐Chrysanthemic Acid from β,γ‐Unsaturated Cyclohexanol
Authors: Krief Alain , Jeanmart Stéphane , Gondal Humaira Y. , Kremer Adrian
Published: November 2012

2,2,5,5‐Tetramethylcyclohexane‐1,3‐dione is a valuable starting‐material precursor of cis‐chrysanthemic acid. The (1S)‐stereoisomer is a precursor of pyrethrin I, the most active natural insecticide from Chrysanthemum cinerariifolium, whereas the (1R)‐stereoisomer is efficiently transformed to deltamethrin, the most active commercially available pyrethroid insecticide. Several intermediates have been identified and used with variable success for that purpose.
Enantioselective Solid‐Phase Peptide Synthesis Using Traceless Chiral Coupling Reagents and Racemic Amino Acids
Authors: Kolesinska Beata , Kasperowicz‐Frankowska Katarzyna , Fraczyk Justyna , Kaminski Zbigniew J.
Published: November 2012

The enantioselective condensing reagent 4,6‐dimethoxy‐1,3,5‐triazine (DMT)/strychnine/BF$\rm{{_{4}^{-}}}$ was obtained by treatment of 2‐chloro‐4,6‐dimethoxy‐1,3,5‐triazine (CDMT) with strychnine tetrafluoroborate. The reagent was useful under typical conditions of solid‐phase peptide synthesis (SPPS) with enantiomerically homogeneous substrates. By SPPS, desired dipeptides were obtained in 84–94% yield using 4 equiv. of racemic Fmoc‐Ala, Fmoc‐Phe, and/or Fmoc‐Tyr for 1 equiv. of Wang resin loaded with Gly, Ala, Leu, Phe, Glu(tBu), and/or Pro, respectively. For all three Fmoc‐protected amino acids, the configuration of the enantiomer preferred under SPPS conditions was independent of the structure of the acylated component and identical to that established in condensations proceeding in solution. In all cases, the enantiomer ratios L/D (er) were in a similar range, and varied from 9 : 92 to 2 : 98 for alanine, and from 90 : 10 to 100 : 0 for aromatic amino acids. The synthesis of Ac‐L‐Lys(Ac)‐D‐Ala‐D‐Ala‐OH from racemic Fmoc‐Ala gave an L/D ratio of 10 : 90 for the esterification of Wang resin, and 0 : 100 for the formation of peptide bonds.
Microwave‐Assisted Synthesis of β‐Lactams and Cyclo‐β‐dipeptides
Authors: Hernández‐Vázquez Luis G. , Leyva Marco A. , Metta‐Magaña Alejandro J. , Escalante Jaime
Published: November 2012

Different cyclo‐β‐dipeptides were prepared from corresponding N‐substituted β‐alanine derivatives under mild conditions using PhPOCl2 as activating agent in benzene and Et3N as base. To evaluate β3‐substituent influence, the amino acids 7–26 were synthesized, and a β‐lactam formation reaction was carried out instead of cyclo‐β‐dipeptide formation. The crystal structures of three derivatives of cyclo‐β‐peptides and one β‐lactam are presented.
Catalytic Enantioselective Synthesis of a 3‐Aryl‐3‐benzyloxindole (=3‐Aryl‐3‐benzyl‐1,3‐dihydro‐2H‐indol‐2‐one) Exhibiting Antitumor Activity
Authors: Katayev Dmitry , Kündig E. Peter
Published: November 2012

A palladium‐catalyzed intramolecular α‐arylation of an amide in the presence of a bulky chiral N‐heterocyclic carbene ligand is the key step in the first catalytic synthesis of (3R)‐6‐chloro‐3‐(3‐chlorobenzyl)‐1,3‐dihydro‐3‐(3‐methoxyphenyl)‐2H‐indol‐2‐one ((R)‐5). This oxindole, in racemic form, had been shown previously to be an anticancer agent. (R)‐5 was obtained with an overall yield of 45% and with 96% enantioselectivity.
The Relationship between Temperamental Negative Affect, Effortful Control, and Sensory Regulation: A New Look
Authors: Gouze Karen R. , Lavigne John V. , Hopkins Joyce , Bryant Fred B. , Lebailly Susan A.
Published: November 2012

Temperamental negative affectivity (NA) and effortful control (EC) have long been of interest to psychologists, but sensory regulation (SR) has received less attention. Using confirmatory factor analysis, the present study reexamined the Rothbart model of EC and NA using the Children's Behavior Questionnaire (CBQ; M.K. Rothbart, S.A. Ahadi, K.L. Hershy, & P. Fisher, 2001), along with alternative models of EC, NA, and SR using the CBQ and Short Sensory Profile. The results failed to replicate the Rothbart model of EC and NA, which includes SR within the EC and NA factors. A good fit was found for a three‐factor model (EC, NA, and SR) that was replicated in a holdout sample. A three‐factor model also showed a good fit when EC, NA, and SR items similar to symptoms of behavior problems were eliminated.
Effect of exercise training combined with isoflavone supplementation on bone and lipids in postmenopausal women: A randomized clinical trial
Authors: Chilibeck Philip D , Vatanparast Hassanali , Pierson Roger , Case Allison , Olatunbosun Olufemi , Whiting Susan J , Beck Thomas J , Pahwa Punam , Biem H Jay
Published: November 2012

We determined the effects of 2 years of exercise training and soy isoflavone supplementation on bone mass and lipids in postmenopausal women provided with calcium and vitamin D. Women were randomized to four groups: exercise training (Ex); isoflavone supplementation (Iso: 165 mg/d [105 mg/d aglycone equivalent]); combined Ex and Iso (ExIso); and placebo (control). Exercise included resistance training (2 days/week) and walking (4 days/week). Our primary outcomes were lumbar spine and hip bone mineral density (BMD). Secondary outcomes included hip geometry, tibia and radius speed of sound (SOS), dynamic balance (6 m backward tandem walking), blood lipids, mammography, and endometrial thickness. A total of 351 women (Ex = 86, Iso = 90, ExIso = 87, control = 88) were randomized, with 298 analyzed at 2 years (Ex = 77, Iso = 76, ExIso = 72, control = 73). There was a significant interaction for total hip BMD (p < 0.001) such that ExIso had a greater rate of decrease (absolute change [95% confidence interval] = −0.018 [−0.024, −0.012] g/cm2) than either the Ex or Iso groups alone (−0.005 [−0.01, 0.001] and −0.005 [−0.011, 0.001] g/cm2, respectively). There were no differences between groups for changes in lumbar spine BMD and minimal significant changes in hip geometric properties and bone SOS. Exercise groups improved dynamic balance as measured by a decrease in backward tandem walking time over 6 m (p = 0.017). Isoflavone groups decreased low density lipoproteins (Iso: −0.20 [−0.37, −0.02] mmol/L; ExIso: −0.23 [−0.40, −0.06] mmol/L; p = 0.003) compared to non-isoflavone groups (Ex: 0.01 [−0.16, 0.18] mmol/L; control: −0.09 [−0.27, 0.08] mmol/L) and had lower adverse reports of menopausal symptoms (14% versus 33%; p = 0.01) compared to non-isoflavone groups. Isoflavone supplementation did not increase endometrial thickness or abnormal mammograms. We conclude exercise training and isoflavone supplementation maintain hip BMD compared to control, but these two interventions interfere with each other when combined. Isoflavone supplementation decreased LDL and adverse events related to menopausal symptoms. © 2013 American Society for Bone and Mineral Research.
Synthesis and Qualitative Analysis of BACy and Its Self‐polymer
Authors: Lin Yan‐Su , Lee Hsuan‐Hsuan , Lee Wen‐Fu , Lin Chao‐Hsiung
Published: November 2012

Many synthetic strategies of a reversible cross‐linker N,N′‐bis(acryloyl)cystamine (BACy) involve the typical condensation between the amino group of cystamine and the acyl group of acryloyl chloride in the mixed‐phase solvent system. In this study, the synthesis of BACy was performed in pure organic phase during the whole process. The yield and purity of synthesized BACy were comparable to those from aqueous/organic phase procedures. In addition, polymerization of BACy was also carried out by free radical reaction to prepare the self‐polymer and hydrogel which were characterized with FT‐IR, DSC and UV/VIS spectrophotometer. Notably, the BACy and its self‐polymer were both cleavable when exposed to the reducing agents, i.e. 1,4‐dithiothreitol (DTT) and 2‐mercaptoethanol (β‐ME). Interestingly, the reduced product of BACy contains vinyl and thiol groups, which could be further applied to the co‐polymerization with other monomeric units. On the other hand, carefully controlled reduction of BACy self‐polymer may be used to create the modified polymers with available thiol‐end groups for further chemistry. Together, our study provides modified procedure for BACy synthesis and characteristics of BACy self‐polymer and hydrogel. Further application of BACy and its self‐polymer in developing polymers with additional functionality is anticipated.
Euphorbiane: A Novel Triterpenoid with an Unprecedented Skeleton from Euphorbia tirucalli
Authors: Yu Hsi‐Jung , Shen Chien‐Chang , Yi Hsiu‐Mei , Chen Tai‐Hung , Hsueh Mao‐Lin , Lin Chu‐Chieh , Don Ming‐Jaw
Published: November 2012

Euphorbiane (1), a novel triterpenoid exhibiting a unique skeleton, together with seven known compounds were isolated from the 95% EtOH extract of the fresh stems of Euphorbia tirucalli. The structure of 1 and relative stereochemistry were elucidated by extensive NMR and a single‐crystal X‐ray crystallographic analysis.
Producing Ethnographies: Workplace Ethnographies in History
Authors: Platt Jennifer , Crothers Charles , Horgan Mervyn
Published: November 2012

Data on a large set of workplace ethnographies published from 1940 to 2002, compiled by Randy Hodson, are analyzed to show the trends over time in the production of such ethnographic work, its shifting disciplinary base, the relevance of the personal backgrounds of its authors, the contributions made by academic amateurs, the changing roles of gender and political stances, and the nature of different routes to publication. The definition of what counts as an ethnography is important to the character of the set available and has implications for its potential uses in secondary analysis. It is found that both personal and disciplinary identities and wider social factors have played roles in the production of ethnographic work that need to be understood to account for its history, though it is to be expected that the forms these take will differ for work in different subfields.
Zolpidem is independently associated with increased risk of inpatient falls
Authors: Kolla Bhanu Prakash , Lovely Jenna K. , Mansukhani Meghna P. , Morgenthaler Timothy I.
Published: November 2012

BACKGROUND:

Inpatient falls are associated with significant morbidity and increased healthcare costs. Zolpidem has been reported to decrease balance and is associated with falls. Yet, it is a commonly used hypnotic agent in the inpatient setting. Zolpidem use in hospitalized patients may be a significant and potentially modifiable risk factor for falling.

OBJECTIVE:

To determine whether inpatients administered zolpidem are at greater risk of falling.

DESIGN:

Retrospective cohort study.

SETTING:

Adult non‐intensive care unit (non‐ICU) inpatients at a tertiary care center.

METHODS:

Adult inpatients who were prescribed zolpidem were identified. Electronic medical records were reviewed to capture demographics and other risk factors for falls. The fall rate was compared in those administered zolpidem versus those only prescribed zolpidem. Multivariate analyses were performed to determine whether zolpidem was independently associated with falls.

RESULTS:

The fall rate among patients who were prescribed and received zolpidem (n = 4962) was significantly greater than among patients who were prescribed but did not receive zolpidem (n = 11,358) (3.04% vs 0.71%; P < 0.001). Zolpidem use continued to remain significantly associated with increased fall risk after accounting for age, gender, insomnia, delirium status, dose of zolpidem, Charlson comorbidity index, Hendrich's fall risk score, length of hospital stay, presence of visual impairment, gait abnormalities, and dementia/cognitive impairment (adjusted odds ratio [OR] 4.37, 95% confidence interval [CI] = 3.34–5.76; P < 0.001). Additionally, patients taking zolpidem who experienced a fall did not differ from other hospitalized adult patients who fell in terms of age, opioids, antidepressants, sedative‐antidepressants, antipsychotics, benzodiazepine, or antihistamine use.

CONCLUSION:

Zolpidem use was a strong, independent, and potentially modifiable risk factor for inpatient falls. Journal of Hospital Medicine 2013. © 2012 Society of Hospital Medicine
Evaluation of chondral repair using quantitative MRI
Authors: Nieminen Miika T. , Nissi Mikko J. , Mattila Lauri , Kiviranta Ilkka
Published: November 2012

Various quantitative magnetic resonance imaging (qMRI) biomarkers, including but not limited to parametric MRI mapping, semiquantitative evaluation, and morphological assessment, have been successfully applied to assess cartilage repair in both animal and human studies. Through the interaction between interstitial water and constituent macromolecules the compositional and structural properties of cartilage can be evaluated. In this review a comprehensive view of a variety of quantitative techniques, particularly those involving parametric mapping, and their relationship to the properties of cartilage repair is presented. Some techniques, such as T2 relaxation time mapping and delayed gadolinium‐enhanced MRI of cartilage (dGEMRIC), are well established, while the full potential of more recently introduced techniques remain to be demonstrated. A combination of several MRI techniques is necessary for a comprehensive characterization of chondral repair. J. Magn. Reson. Imaging 2012; 36:1287–1299. © 2012 Wiley Periodicals, Inc.
Assessment of contrast‐enhanced computed tomography for imaging of cartilage during fracture healing
Authors: Hayward Lauren N.M. , de Bakker Chantal M.J. , Gerstenfeld Louis C. , Grinstaff Mark W. , Morgan Elise F.
Published: November 2012

Assessment of the early stages of fracture healing via X‐rays and computed tomography is limited by the low radio‐opacity of cartilage. We validated a method of contrast‐enhanced computed tomography (CECT) for non‐destructive identification of cartilage within a healing fracture callus. Closed, stabilized fractures in femora of C57BL/6 mice were harvested on post‐operative day 9.5 and imaged ex vivo with micro‐computed tomography (µCT) before and after incubation in a cationic contrast agent that preferentially accumulates in cartilage due to the high concentration of sulfated glycosaminoglycans in the tissue. Co‐registration of the pre‐ and post‐incubation images, followed by image subtraction, enabled two‐ and three‐dimensional delineation of mineralized tissue, soft callus, and cartilage. The areas of cartilage and callus identified with CECT were compared to those identified with the gold‐standard method of histomorphometry. No difference was found between the areas of cartilage measured by the two methods (p = 0.999). Callus area measured by CECT was smaller than, but strongly predictive of (R2 = 0.80, p < 0.001), the corresponding histomorphometric measurements. CECT also enabled qualitative identification of mineralized cartilage. These findings indicate that the CECT method provides accurate, quantitative, and non‐destructive visualization of the shape and composition of the fracture callus, even during the early stages of repair when little mineralized tissue is present. The non‐destructive nature of this method would allow subsequent analyses, such as mechanical testing, to be performed on the callus, thus enabling higher‐throughput, comprehensive investigations of bone healing. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 567–573, 2013
Fast microwave‐assisted extraction of rotenone for its quantification in seeds of yam bean (Pachyrhizus sp.)
Authors: Lautié Emmanuelle , Rasse Catherine , Rozet Eric , Mourgues Claire , Vanhelleputte Jean‐Paul , Quetin‐Leclercq Joëlle
Published: November 2012

The aim of this study was to find if fast microwave‐assisted extraction could be an alternative to the conventional Soxhlet extraction for the quantification of rotenone in yam bean seeds by SPE and HPLC‐UV. For this purpose, an experimental design was used to determine the optimal conditions of the microwave extraction. Then the values of the quantification on three accessions from two different species of yam bean seeds were compared using the two different kinds of extraction. A microwave extraction of 11 min at 55°C using methanol/dichloromethane (50:50) allowed rotenone extraction either equivalently or more efficiently than the 8‐h‐Soxhlet extraction method and was less sensitive to moisture content. The selectivity, precision, trueness, accuracy, and limit of quantification of the method with microwave extraction were also demonstrated.
Quantification of 5‐aminolevulinic acid by CE using dynamic pH junction technique
Authors: Hsieh Bo‐Chuan , Chen Richie L. C. , Tsai Tsuimin
Published: November 2012

An online dynamic pH junction preconcentration method was developed for quantification of 5‐aminolevulinic acid (ALA) by CE with the separation time less than 6 min. The optimal dynamic pH junction of ALA was carried out between pH 9.3 borate buffer (BGE, 40 mM) and pH 2.5 phosphate buffer (sample matrix, 40 mM) when 4.1 cm of sample plug was hydrodynamically injected into an uncoated fused‐silica capillary (48.5 cm in length, id of 50 μm). If a 24 kV separation voltage was applied, the calibration curve of ALA peak area (200 nm) showed good linearity (R2 = 0.9991) ranging from 0.01 to 6.5 mg/mL. The reproducibility of this system was excellent with RSDs (n = 10) of 2.5% for peak area response and 0.6% for migration time at ALA concentration of 0.5 mg/mL. The LOD was evaluated as 1.0 μg/mL (S/N > 3). Compared to conventional CE procedure, the sensitivity was successfully improved over 50‐fold. The analytical results of pharmaceutical formulations show a good agreement with those by HPLC (r = 0.94).
Michrochip chromatography using an open‐tubular microchannel and a ternary water–ACN–ethyl acetate mixture carrier solution
Authors: Matsuda Takafumi , Yamashita Kenichi , Maeda Hideaki , Hashimoto Masahiko , Tsukagoshi Kazuhiko
Published: November 2012

A capillary chromatography system has been developed using a ternary mixed‐solvents solution, i.e. water–hydrophilic/hydrophobic organic solvent mixture as a carrier solution. Here, we tried to carry out the chromatographic system on a microchip incorporating the open‐tubular microchannels. A model analyte solution of isoluminol isothiocyanate (ILITC) and ILITC‐labeled biomolecule was injected to the double T‐junction part on the microchip. The analyte solution was delivered in the separation microchannel (40 μm deep, 100 μm wide, and 22 cm long) with the ternary water–ACN–ethyl acetate mixture carrier solution (3:8:4 volume ratio, the organic solvent rich or 15:3:2 volume ratio, the water‐rich). The analyte, free‐ILITC and labeled BSA mixture, was separated through the microchannel, where the carrier solvents were radially distributed in the separation channel generating inner and outer phases. The outer phase acts as a pseudo‐stationary phase under laminar flow conditions in the system. The ILITC and the labeled BSA were eluted and detected with chemiluminescence reaction.
Forced degradation studies of clobetasol 17‐propionate in methanol, propylene glycol, as bulk drug and cream formulations by RP‐HPLC
Authors: Fauzee Ayeshah Fateemah Beebee , Walker Roderick Bryan
Published: November 2012

A rapid, simple, stability‐indicating forced degradation study of clobetasol 17‐propionate was conducted using RP‐HPLC. The method was used to analyze clobetasol 17‐propionate in methanol, propylene glycol, and a cream formulation. Isocratic elution of clobetasol and its degradation products was achieved using a Nova‐Pak® 4 μm C18 150 mm × 3.9 mm id cartridge column and a mobile phase of methanol: water (68:32 v/v) at a flow rate of 0.9 mL min−1. Quantitation was achieved with UV detection at 239 nm. Nondegraded clobetasol was eluted at a retention time of 6.0 min. Clobetasol 17‐propionate was subjected to different stress conditions viz., acidic, basic, heat, oxidation, light, and neutral hydrolysis. The greatest degradation occurred under strong base and oxidative conditions. Strong base‐degraded clobetasol produced additional peaks at retention times of 1.8, 4.0, 5.0, and 8.0 min and clobetasol oxidation degradation peaks eluted at 2.2 and 24 min. Complete validation was performed for linearity, accuracy, and precision over the concentration range 0.15–15 μg mL−1. All data were analyzed statistically and this RP‐HPLC method proved to be accurate, precise, linear, and stability indicating for the quantitation of clobetasol 17‐propionate in methanol, propylene glycol, and cream formulations.
In vitro 3D Full‐Thickness Skin‐Equivalent Tissue Model Using Silk and Collagen Biomaterials
Authors: Bellas Evangelia , Seiberg Miri , Garlick Jonathan , Kaplan David L.
Published: November 2012

Current approaches to skin equivalents often only include the epidermis and dermis. Here, a full‐thickness skin equivalent is described including epidermis, dermis, and hypodermis, that could serve as an in vitro model for studying skin biology or as a platform for consumer product testing. The construct is easy to handle and is maintained for >14 d while expressing physiological morphologies of the epidermis and dermis, seen by keratin 10, collagens I and IV expression. The skin equivalent produces glycerol and leptin, markers of adipose metabolism. This work serves as a foundation for understanding a few necessary factors needed to develop a stable, functional model of full‐thickness skin.

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Which Polyesters Can Mimic Polyethylene?
Authors: Stempfle Florian , Ortmann Patrick , Mecking Stefan
Published: November 2012

Self‐metathesis of erucic acid by [(PCy3)(η‐C‐C3H4N2Mes2)Cl2Ru = CHPh] (Grubbs second‐ generation catalyst) followed by catalytic hydrogenation and purification via the ester yields 1,26‐hexacosanedioate (>99% purity). Polyesterification with 1,26‐hexacosanediol, generated from the diester, affords polyester‐26,26, which features a Tm of 114 °C (Tc = 92 °C, ΔHm = 160 J g−1). Ultralong‐chain model polyesters‐38,23 (Tm = 109 °C) and −44,23 (Tm = 111 °C), generated via multistep procedures including acyclic diene metathesis polymerization, underline that melting points of such aliphatic polyesters do not gradually increase with methylene sequence chain length. Available data suggest that to mimic linear polyethylenes thermal properties, even longer sequences, amounting to at least four times a fatty acid chain, fully incorporated in a linear fashion are required.
Proteomics analysis of tumor microenvironment: Implications of metabolic and oxidative stresses in tumorigenesis
Authors: Zhou Shengtao , Liu Rui , Yuan Kefei , Yi Tao , Zhao Xia , Huang Canhua , Wei Yuquan
Published: November 2012

Tumorigenesis is always concomitant with microenvironmental alterations. The tumor microenvironment is a heterogeneous and complex milieu, which exerts a variety of stresses on tumor cells for proliferation, survival, or death. Recently, accumulated evidence revealed that metabolic and oxidative stresses both play significant roles in tumor development and progression that converge on a common autophagic pathway. Tumor cells display increased metabolic autonomy, and the hallmark is the exploitation of aerobic glycolysis (termed Warburg effect), which increased glucose consumption and decreased oxidative phosphorylation to support growth and proliferation. This characteristic renders cancer cells more aggressive; they devour tremendous amounts of nutrients from microenvironment to result in an ever‐growing appetite for new tumor vessel formation and the release of more “waste,” including key determinants of cell fate like lactate and reactive oxygen species (ROS). The intracellular ROS level of cancer cells can also be modulated by a variety of stimuli in the tumor microenvironment, such as pro‐growth and pro‐inflammatory factors. The intracellular redox state serves as a double‐edged sword in tumor development and progression: ROS overproduction results in cytotoxic effects and might lead to apoptotic cell death, whereas certain level of ROS can act as a second‐messenger for regulation of such cellular processes as cell survival, proliferation, and metastasis. The molecular mechanisms for cancer cell responses to metabolic and oxidative stresses are complex and are likely to involve multiple molecules or signaling pathways. In addition, the expression and modification of these proteins after metabolic or oxidative stress challenge are diverse in different cancer cells and endow them with different functions. Therefore, MS‐based high‐throughput platforms, such as proteomics, are indispensable in the global analysis of cancer cell responses to metabolic and oxidative stress. Herein, we highlight recent advances in the understanding of the metabolic and oxidative stresses associated with tumor progression with proteomics‐based systems biology approaches. © 2012 Wiley Periodicals, Inc., Mass Spec Rev 32:267–311, 2013
Effectiveness of multidisciplinary care for Parkinson's disease: A randomized, controlled trial
Authors: van der Marck Marjolein A. , Bloem Bastiaan R. , Borm George F. , Overeem Sebastiaan , Munneke Marten , Guttman Mark
Published: November 2012

Multidisciplinary care is considered an optimal model to manage Parkinson's disease (PD), but supporting evidence is limited. We performed a randomized, controlled trial (RCT) to establish whether a multidisciplinary/specialist team offers better outcomes, compared to stand‐alone care from a general neurologist. Patients with PD were randomly allocated to an intervention group (care from a movement disorders specialist, PD nurses, and social worker) or a control group (care from general neurologists). Both interventions lasted 8 months. Clinicians and researchers were blinded for group allocation. The primary outcome was the change in quality of life (Parkinson's Disease Questionnaire; PDQ‐39) from baseline to 8 months. Other outcomes were the UPDRS, depression (Montgomery‐Asberg Depression Scale; MADRS), psychosocial functioning (Scales for Outcomes in Parkinson's disease‐Psychosocial; SCOPA‐PS), and caregiver strain (Caregiver Strain Index; CSI). Group differences were analyzed using analysis of covariance adjusted for baseline values and presence of response fluctuations. A total of 122 patients were randomized and 100 completed the study (intervention, n = 51; control, n = 49). Compared to controls, the intervention group improved significantly on PDQ‐39 (difference, 3.4; 95% confidence interval [CI]: 0.5–6.2) and UPDRS motor scores (4.1; 95% CI: 0.8–7.3). UPDRS total score (5.6; 95% CI: 0.9–10.3), MADRS (3.7; 95% CI: 1.4–5.9), and SCOPA‐PS (2.1; 95% CI: 0.5–3.7) also improved significantly. This RCT gives credence to a multidisciplinary/specialist team approach. We interpret these positive findings cautiously because of the limitations in study design. Further research is required to assess teams involving additional disciplines and to evaluate cost‐effectiveness of integrated approaches. © 2012 Movement Disorder Society
Free hemiback flap with surgical delay for reconstruction of extensive soft tissue defect: A case report
Authors: Fujiwara Masao , Nagata Takeshi , Matsushita Yuki , Fukamizu Hidekazu
Published: November 2012

A delay procedure allows for reliable tissue transfer in random pattern flaps and axial pattern flaps. However, delay procedures have not been studied in free flaps. In this report, we present a case involving the use of a free extended latissimus dorsi musculocutaneous flap (hemiback flap) that included half of the total back skin and was based on thoracodorsal vessels for reconstruction of an extensive soft tissue defect of the flank and waist. The flap was tailored in combination with a delay procedure. Intraoperative indocyanine green fluorescence angiography indicated profuse perfusion except for the most inferomedial part of the flap, which was discarded. The flap survived. A free hemiback flap may offer a valuable option for reconstruction of extensive soft tissue defects. To our knowledge, this is the first report to demonstrate a free flap made in combination with a delay procedure. © 2012 Wiley Periodicals, Inc. Microsurgery, 2013.
Grape seed proanthocyanidin extracts alleviate oxidative stress and ER stress in skeletal muscle of low‐dose streptozotocin‐ and high‐carbohydrate/high‐fat diet‐induced diabetic rats
Authors: Ding Ye , Dai Xiaoqian , Jiang Yanfei , Zhang Zhaofeng , Bao Lei , Li Yujie , Zhang Feng , Ma Xiaotao , Cai Xiaxia , Jing Lulu , Gu Jiaojiao , Li Yong
Published: November 2012

Although ER stress in pancreas, liver, and adipose tissue was reported to be a novel event linked to the pathogenesis of type 2 diabetes mellitus, there is much less information on this event in skeletal muscle. Some studies indicated that treatment with antioxidants had beneficial effects on ER stress and diabetes. This study focuses on the effects of a strong antioxidant, grape seed proanthocyanidin extracts (GSPE), on skeletal muscle in diabetic rats induced with low dose streptozotocin‐ and a high‐carbohydrate/high‐fat diet. After 16 wk of GSPE treatment, diabetic rats showed decreased plasma glucose levels and insulin resistance. The efficacious effect of GSPE was manifested by the amelioration of muscular damage and dysfunction, as observed by histological examination and periodic acid Schiff staining. Concurrently, calcium overload and the abnormal activities of antioxidant enzymes and ATPases in diabetic muscles were partially reversed by GSPE treatment. GSPE also increased the activity of protein kinase B (a mediator of insulin's metabolic action) and partially alleviated severe ER stress. These findings suggest that GSPE may have auxiliary therapeutic potential for type 2 diabetes mellitus by decreasing oxidative stress and ER stress in skeletal muscle.
Initial feasibility testing of limited field of view magnetic resonance thermometry using a local cardiac radiofrequency coil
Authors: Volland Nelly A. , Kholmovski Eugene G. , Parker Dennis L. , Hadley J. Rock
Published: November 2012

The visualization of lesion formation in real time is one potential benefit of carrying out radiofrequency ablation under magnetic resonance (MR) guidance in the treatment of atrial fibrillation. MR thermometry has the potential to detect such lesions. However, performing MR thermometry during cardiac radiofrequency ablation requires high temporal and spatial resolution and a high signal‐to‐noise ratio. In this study, a local MR coil (2‐cm diameter) was developed to investigate the feasibility of performing limited field of view MR thermometry with high accuracy and speed. The local MR coil allowed high‐resolution (1 × 1 × 3 mm3) image acquisitions in 76.3 ms with a field of view 64 × 32 mm2 during an open‐chest animal experiment. This represents a 4‐fold image acquisition acceleration and an 18‐fold field of view reduction compared to that achieved using external MR coils. The signal sensitivity achieved using the local coil was over 20 times greater than that achievable using external coils with the same scan parameters. The local coil configuration provided fewer artifacts and sharper and more stable images. These results demonstrate that MR thermometry can be performed in the heart wall and that lesion formation can be observed during radiofrequency ablation procedures in a canine model. Magn Reson Med, 70:994–1004, 2013. © 2012 Wiley Periodicals, Inc.>
T2 relaxometry with indirect echo compensation from highly undersampled data
Authors: Huang Chuan , Bilgin Ali , Barr Tomoe , Altbach Maria I.
Published: November 2012

Purpose

To develop an algorithm for fast and accurate T2 estimation from highly undersampled multi‐echo spin‐echo data.

Methods

The algorithm combines a model‐based reconstruction with a signal decay based on the slice‐resolved extended phase graph (SEPG) model with the goal of reconstructing T2 maps from highly undersampled radial multi‐echo spin‐echo data with indirect echo compensation. To avoid problems associated with the nonlinearity of the SEPG model, principal component decomposition is used to linearize the signal model. The proposed CUrve Reconstruction via principal component‐based Linearization with Indirect Echo compensation (CURLIE) algorithm is used to estimate T2 curves from highly undersampled data. T2 maps are obtained by fitting the curves to the SEPG model.

Results

Results on phantoms showed T2 biases (1.9% to 18.4%) when indirect echoes are not taken into account. The T2 biases were reduced (< 3.2%) when the CURLIE reconstruction was performed along with SEPG fitting even for high degrees of undersampling (4% sampled). Experiments in vivo for brain, liver, and heart followed the same trend as the phantoms.

Conclusion

The CURLIE reconstruction combined with SEPG fitting enables accurate T2 estimation from highly undersampled multi‐echo spin‐echo radial data thus, yielding a fast T2 mapping method without errors caused by indirect echoes. Magn Reson Med, 70:1026–1037, 2013. © 2012 Wiley Periodicals, Inc.
Head and flagella subcompartmental proteomic analysis of human spermatozoa
Authors: Baker Mark A. , Naumovski Nenad , Hetherington Louise , Weinberg Anita , Velkov Tony , Aitken R. John
Published: November 2012

Subcellular proteomics not only deepens our knowledge of what proteins are present within cells, but also opens our understanding as to where those proteins reside. Given the highly differentiated, cross‐linked state of spermatozoa, such studies have proven difficult to perform. In this study we have fractionated spermatozoa into two components, consisting of either the head or flagellar region. Following SDS‐PAGE, 1 mm slices were digested and used for LC‐MS/MS analysis. In total, 1429 proteins were identified with 721 proteins being exclusively found in the tail and 521 exclusively in the head. Not only is this the largest reported proteomic analysis of human spermatozoa, but also it has provided novel insights into the compartmentalization of proteins, particularly receptors, never previously reported to be present in this cell type.
Cobalt(III)‐complex‐mediated terpolymerization of CO2, styrene oxide, and epoxides with an electron‐donating group
Authors: Wu Guang‐Peng , Xu Peng‐Xiang , Zu Yu‐Ping , Ren Wei‐Min , Lu Xiao‐Bing
Published: November 2012

Terpolymerizations of CO2, styrene oxide (SO), and epoxides with an electron‐donating group such as propylene oxide (PO) or cyclohexene oxide (CHO) were carried out by using Co(III)–salen complexes in the presence of an intra‐ or intermolecular nucleophilic cocatalyst. The resultant terpolymers have only one thermolysis peak and one glass transition temperature (Tg), which can be easily adjusted by controlling the proportion of styrene carbonate linkages. During the CO2/SO/PO terpolymerization, the monomer reactivity ratios (rSO = 0.18 and rPO = 2.25) evaluated by Fineman–Ross plot indicates a random distribution of the two kinds of carbonate units in the resultant polymer. Contrarily, the monomer reactivity ratios were found to be rSO = 0.48 and rCHO = 0.79 in the CO2/SO/CHO terpolymerization, indicating that an alternating nature of the two different carbonate units predominantly exists in the resultant polycarbonate. The regioselective ring opening of SO has a significant effect on the reactivities of both SO and CHO during the terpolymerization with CO2. The matched reactivity is contributed to the enhanced regioselective ring opening of SO, caused by the attack of the dissociating polymer carboxylate anion, bearing a cyclohexene carbonate end unit. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
Quantitative mass spectrometry‐based proteomics in angiogenesis
Authors: Hernandez‐Fernaud Juan Ramon , Reid Steven E. , Neilson Lisa J. , Zanivan Sara
Published: November 2012

The process of new blood vessel formation from pre‐existing ones is called angiogenesis. Beyond playing a critical role in the physiological development of the vascular system, angiogenesis is a well‐recognised hallmark of cancer. Unbiased system‐wide approaches are required to complement the current knowledge, and intimately understand the molecular mechanisms regulating this process in physiological and pathological conditions. In this review we describe the cellular and molecular dynamics regulating the physiological growth of vessels and their deregulation in cancer, survey in vitro and in vivo models currently exploited to investigate various aspects of angiogenesis and describe state‐of‐the‐art and most widespread methods and technologies in MS shotgun proteomics. Finally, we focus on current applications of MS to better understand endothelial cell behaviour and propose how modern proteomics can impact on angiogenesis research.
Rigid‐plane phonons in layered crystals
Authors: Michel K. H. , Verberck B.
Published: November 2012

The determination of the layer number ${\cal N}$ in nanoscale thin layered crystals is a challenging problem of technological relevance. In addition to innovative experimental techniques, a thorough knowledge of the underlying lattice dynamics is required. Starting from phenomenological atomic interaction potentials we have carried out an analytical study of the low‐frequency optical phonon dispersions in layered crystals. At the gamma point of the two‐dimensional Brillouin zone the optical phonon frequencies correspond to rigid‐plane shearing and compression modes. We have investigated graphene multilayers (GML) and hexagonal boron‐nitride multilayers (BNML). The frequencies show a characteristic dependence on ${\cal N}$. The results which are represented in the form of fan diagrams are very similar for both materials. Due to charge neutrality within layers Coulomb forces play no role, only van der Waals forces between nearest neighbor layers are relevant. The theoretical results agree with recent low‐frequency Raman results on rigid‐layer modes [Tan et al., Nature Mater. 11, 294 (2012)] in GML and double‐resonant Raman scattering data on rigid‐layer compression modes [Herziger et al., Phys. Rev. B 85, 235447 (2012)] in GML.
Lithium fluoride crystal as a novel high dynamic neutron imaging detector with microns scale spatial resolution
Authors: Faenov Anatoly , Matsubayashi Masahito , Pikuz Tatiana , Fukuda Yuji , Kando Masaki , Yasuda Ryo , Iikura Hiroshi , Nojima Takehiro , Sakai Takuro , Shiozawa Masahiro , Kato Yoshiaki
Published: November 2012

Recently, a new field of application of optically stimulated luminescence of color centers (CCs) in lithium fluoride (LiF) crystals was proposed – using them for high‐performance neutron imaging – and promising results were obtained (Matsubayashi et al., Nucl. Instrum. Methods A 622, 637 (2010) and Matsubayashi et al., Nucl. Instrum. Methods A 651, 90 (2011)). Here we present the overview of main findings, which clearly demonstrated that the LiF crystal performs efficiently as neutron imaging detector in areas, where a high spatial resolution with a high image gradation resolution is needed. It was shown that the obtained neutron images are almost free from granular noises, have spatial resolution of ∼ 6 μm, and have practically linear response with the dynamic range of at least 103. It was also found that the LiF crystal detector offers a fairly good sensitivity. Moreover, detailed evaluation using a standard sensitivity indicator for neutron radiography showed that two holes with less than 2% transmittance differences could be distinguished. Additionally, we recently demonstrated that the high resolution neutron imaging with LiF crystals could be useful for quantitative characterizations of neutron sources and electric devices, comprising of low‐Z elements, for example, such as fuel cells. All of this gives new opportunity for microns scale spatial resolution imaging by neutrons (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photoluminescence dynamics originating from exciton‐exciton and exciton‐electron scattering in a GaN thin film
Authors: Wakaiki Shuji , Tokumaru Hitoshi , Ichida Hideki , Mizoguchi Kohji , Kim DaeGwi , Kanematsu Yasuo , Nakayama Masaaki
Published: November 2012

We have investigated the photoluminescence (PL) dynamics of a GaN thin film under intense excitation conditions using an optical‐Kerr‐gating method. It has been found that the PL originating from the exciton‐exciton scattering (P emission) appears at the temperatures lower than around 100 K, while at higher temperatures P emission vanishes and the PL originating from exciton‐electron scattering (H emission) dominates. The ultrashort gating time of 0.6 ps enabled us to obtain precise information of the temporal profiles of the peak energy, the bandwidth, and the intensity of the P emission and H emission. We have found that the decay time of the H emission is shorter than that of the P emission. By taking into account the strong correlation between the decay time and the peak‐energy position of the emissions, we conclude that the difference in the decay times is attributed to a change of the photon‐like characteristics of the lower polariton branch that is the final state of the scattering process; namely, the photon‐like component of the H emission is larger than that of the P emission. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)