bluuebunny/crossref_metadata_2025 huggingface dataset:
Cerebral hemodynamics in newborn infants exposed to speech sounds: A whole‐head optical topography study
Authors: Sato Hiroki , Hirabayashi Yukiko , Tsubokura Hifumi , Kanai Makoto , Ashida Takashi , Konishi Ikuo , Uchida‐Ota Mariko , Konishi Yukuo , Maki Atsushi
Published: June 2011

Considerable knowledge on neural development related to speech perception has been obtained by functional imaging studies using near‐infrared spectroscopy (optical topography). In particular, a pioneering study showed stronger left‐dominant activation in the temporal lobe for (normal) forward speech (FW) than for (reversed) backward speech (BW) in neonates. However, it is unclear whether this stronger left‐dominant activation for FW is equally observed for any language or is clearer for the mother tongue. We hypothesized that the maternal language elicits clearer activation than a foreign language in newborns because of their prenatal and/or few‐day postnatal exposure to the maternal language. To test this hypothesis, we developed a whole‐head optode cap for 72‐channel optical topography and visualized the spatiotemporal hemodynamics in the brains of 17 Japanese newborns when they were exposed to FW and BW in their maternal language (Japanese) and in a foreign language (English). Statistical analysis showed that all sound stimuli together induced significant activation in the bilateral temporal regions and the frontal region. They also showed that the left temporal‐parietal region was significantly more active for Japanese FW than Japanese BW or English FW, while no significant difference between FW and BW was shown for English. This supports our hypothesis and suggests that the few‐day‐old brain begins to become attuned to the maternal language. Together with a finding of equivalent activation for all sound stimuli in the adjacent measurement positions in the temporal region, these findings further clarify the functional organization of the neonatal brain. Hum Brain Mapp 33:2092–2103, 2012. © 2011 Wiley Periodicals, Inc.
Interleukin‐23 receptor polymorphism as a risk factor for oral cancer susceptibility
Authors: Chien Ming‐Hsien , Hsin Chung‐Han , Shih‐Shen Chou Lin , Chung Tsung‐Te , Lin Chien‐Huang , Weng Meng‐Shih , Chou Ming‐Yung , Chen Mu‐Kuan , Yang Shun‐Fa
Published: June 2011

Background

The purpose of this study was to evaluate the influence of genetic polymorphisms of interleukin (IL)‐23 and the IL‐23 receptor (IL‐23R) on the susceptibility to oral cancer.

Methods

Polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) was used to measure polymorphisms of these genes in 240 controls and 240 patients with oral cancer.

Results

Individuals with at least 1 varied C allele of rs10889677 (IL‐23R polymorphism) had a 1.553‐fold risk (95% confidence interval [CI], 1.073–2.241) of developing oral cancer compared with patients with the wild‐type A/A homozygote. Patients with oral cancer with at least 1 varied C allele of rs10889677 had a 1.931‐fold risk of tumor lymph node metastasis compared with patients with the C/C homozygote.

Conclusion

The varied C allele of the IL‐23R gene may be considered a factor contributing to increased susceptibility and may be a predictive factor for tumor lymph node metastasis in Taiwanese with oral cancer. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Rate and historical change of direct recharge from precipitation constrained by unsaturated zone profiles of chloride and oxygen‐18 in dry river bed of North China Plain
Authors: Yuan Ruiqiang , Song Xianfang , Han Dongmei , Zhang Yinghua , Zhang Liang , Zhang Bing , Long Xiting , Yu Yilei
Published: June 2011

Quantifying of direct recharge derived from precipitation is crucial for assessing sustainability of well‐irrigated agriculture. In the North China Plain, the land use is dominated by groundwater‐irrigated farmland where the direct recharge derived from precipitation and irrigation. To characterize the mean rate and historical variance of direct recharge derived from precipitation, unsaturated zone profiles of chloride and δ18O in the dry river bed of the Beiyishui River were employed. The results show that archival time scale of the profile covers the duration from 1980 to 2002 (corresponding to depths from 5 to 2 m) which is indicated by matching the δ18O peaks in the isotope profile with the aridity indexes gained by instrumental records of annual precipitation and annual potential evaporation. Using the chloride mass balance method, the mean rate of the direct recharge corresponding to the archival time scale is estimated to be 3·8 ± 0·8 mm year−1, which accounts for about 0·7% of the long‐term average annual precipitation. Further, the direct recharge rates vary from 2·1 to 6·8 mm year−1 since 1980. Despite the subhumid climate, the estimate of recharge rates is in line with other findings in semiarid regions. The low rate of direct recharge is considered as a result of the relative dry climate in recent decades. In dry river bed, unsaturated zone profiles of chloride and δ18O combined with instrumental records could offer valuable information about the direct recharge derived from precipitation during droughts. Copyright © 2011 John Wiley & Sons, Ltd.
PD‐1 expression on Melan‐A‐reactive T cells increases during progression to metastatic disease
Authors: Krönig Holger , Julia Falchner Kathrin , Odendahl Marcus , Brackertz Bettina , Conrad Heinke , Muck Dieter , Hein Rüdiger , Blank Christian , Peschel Christian , Haller Bernhard , Schulz Stephan , Bernhard Helga
Published: June 2011

Programmed death 1 (PD‐1) is known as an important factor for the development of tolerogenicity. This has been proven in chronic viral infections and different tumor models. To address the role of PD‐1 and its ligand programmed death ligand 1 (PD‐L1) in different stages of malignant melanoma, we investigated peripheral blood and tumor tissues in regard to overall survival (OS) and prognostic relevance. One hundred samples of peripheral blood mononuclear cells from HLA‐A2+ patients with malignant melanoma (Stages I–IV) were analyzed in seven color FACS combined with multimer analyses for the immunodominant epitope of Melan‐A (peptide A2/Melan‐Ap26‐35mod). Corresponding formalin‐fixed paraffin‐embedded tissues of primary tumor and distant organ metastases from 37 cases were analyzed by immunohistochemistry for Melan‐A, PD‐L1 and PD‐1 expression. Compared to the total CD8+ T cell population, PD‐1 expression by A2/Melan‐A+ CD8+ T cells was over‐represented in melanoma stages III and IV (p < 0.001). Although elevation of PD‐1+ Melan‐A+ CD8+ T cells had no significant influence on OS, a positive correlation was observed between PD‐L1 expression on melanoma cells and OS (p = 0.05). Correlation of advanced tumor stage with increased A2/Melan‐A‐multimer+ PD‐1+ T cells in the peripheral blood suggest that blocking of PD‐1 could have therapeutic potential in advanced stage melanoma.
Chiral Amplification, Kinetic Pathways, and Morphogenesis of Helical Nanorods upon Self‐assembly of Dipolar Merocyanine Dyes
Authors: Lohr Andreas , Würthner Frank
Published: June 2011

In this account we report on the self‐assembly of bis(merocyanine) dyes into helical nanorods by emphasizing the kinetic pathways and the mechanistic aspects leading to chiral amplification. A complex self‐assembly sequence of these dipolar dyes into well‐defined helical nanorod structures has been revealed spectroscopically by time‐dependent circular dichroism (CD) spectroscopy and microscopically by atomic force microscopy (AFM). This self‐assembly sequence proceeds over several kinetically formed supramolecular intermediates, which are distinguished by their morphology and (chir)optical properties. Moreover, the kinetics for the formation of homochiral nanorods was studied, revealing that chiral amplification mechanisms can operate at different stages of self‐assembly to afford energetically favored structures. The rates of these processes decrease strongly with decreasing chiral bias in the monomers or decreasing fraction of chiral co‐monomers in mixtures of chiral and achiral monomers. For the fully equilibrated nanorods, however, strong chiral amplification directed by the “majority‐rules” or “sergeants‐and‐soldiers” effect is observed.
Comparative study of the viscoelastic mechanical behavior of agarose and poly(ethylene glycol) hydrogels
Authors: Roberts Justine J. , Earnshaw Audrey , Ferguson Virginia L. , Bryant Stephanie J.
Published: June 2011

This study presents a comparative investigation into differences in the mechanical properties between two hydrogels commonly used in cartilage tissue engineering [agarose vs. poly(ethylene glycol) (PEG)], but which are formed through distinctly different crosslinking mechanisms (physical vs. covalent, respectively). The effects of hydrogel chemistry, precursor concentration, platen type (nonporous vs. porous) used in compression bioreactors, and degradation (for PEG) on the swelling properties and static and dynamic mechanical properties were examined. An increase in precursor concentration resulted in decreased equilibrium mass swelling ratios but increased equilibrium moduli and storage moduli for both hydrogels (p < 0.05). Agarose displayed large stress relaxations and a frequency dependence indicating its viscoelastic properties. Contrarily, PEG hydrogels displayed largely elastic behavior with minimal stress relaxation and frequency dependence. In biodegradable PEG hydrogels, the largely elastic behavior was retained during degradation. The type of platen did not affect static mechanical properties, but porous platens led to a reduced storage modulus for both hydrogels implicating fluid flow. In summary, agarose and PEG exhibit vastly different mechanical behaviors; a finding largely attributed to differences in their chemistries and fluid movement. Taken together, these design choices (hydrogel chemistry/structure, loading conditions) will likely have a profound effect on the tissue engineering outcome. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Surface characterization of Ti and Y‐TZP following non‐thermal plasma exposure
Authors: Silva Nelson R.F.A. , Coelho Paulo G. , Valverde Guilherme B. , Becker Kurt , Ihrke Roland , Quade Antje , Thompson Van P.
Published: June 2011

Novel non‐thermal plasma (NTP) technology has the potential to address the bonding issues of Y‐TZP and Ti surfaces. This study aims to chemically characterize and evaluate the surface energy (SE) of Y‐TZP and Ti surfaces after NTP application. Y‐TZP and Ti discs were treated with a hand‐held NTP device followed by SE evaluation. Spectra of Y‐TZP 3d and Ti 2p regions, survey scans, and quantification of the elements were performed via X‐ray photoelectron Spectroscopy (XPS) prior and after NTP. Separate Y‐TZP and Ti discs were NTP treated for contact angle readings using (10‐methacryloyloxydecyl dihydrogenphosphate) MDP primer. Significant augmentation of SE values was observed in all NTP treated groups. XPS detected a large increase in the O element fraction on both Y‐TZP and Ti surfaces. Reduction of contact angle reading was obtained when the MDP primer was placed on NTP treated Y‐TZP. Ti surface showed high SE before and after NTP application on Ti surfaces. NTP decreased C and increased O on both surfaces independently of application protocol. Wettability of MDP primer on Y‐TZP was significantly increased after NTP. The high polarity obtained on Y‐TZP and Ti surfaces after NTP applications appear promising to enhance bonds. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Determination of the slow crack growth susceptibility coefficient of dental ceramics using different methods
Authors: Gonzaga Carla Castiglia , Cesar Paulo Francisco , Miranda Walter Gomes , Yoshimura Humberto Naoyuki
Published: June 2011

This study compared three methods for the determination of the slow crack growth susceptibility coefficient (n) of two veneering ceramics (VM7 and d.Sign), two glass‐ceramics (Empress and Empress 2) and a glass‐infiltrated alumina composite (In‐Ceram Alumina). Discs (n = 10) were prepared according to manufacturers' recommendations and polished. The constant stress‐rate test was performed at five constant stress rates to calculate nd. For the indentation fracture test to determine nIF, Vickers indentations were performed and the crack lengths were measured under an optical microscope. For the constant stress test (performed only for d.Sign for the determination of ns) four constant stresses were applied and held constant until the specimens' fracture and the time to failure was recorded. All tests were performed in artificial saliva at 37°C. The nd values were 17.2 for Empress 2, followed by d.Sign (20.5), VM7 (26.5), Empress (30.2), and In‐Ceram Alumina (31.1). In‐Ceram Alumina and Empress 2 showed the highest nIF values, 66.0 and 40.2, respectively. The nIF values determined for Empress (25.2), d.Sign (25.6), and VM7 (20.1) were similar. The ns value determined for d.Sign was 31.4. It can be concluded that the n values determined for the dental ceramics evaluated were significantly influenced by the test method used. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Induction plasma sprayed Sr and Mg doped nano hydroxyapatite coatings on Ti for bone implant
Authors: Roy Mangal , Bandyopadhyay Amit , Bose Susmita
Published: June 2011

In this study, we report fabrication of strontium (Sr) and magnesium (Mg) doped hydroxyapatite (HA) coating on commercially pure titanium (Cp‐Ti) substrates using inductively coupled radio frequency (RF) plasma spray. HA powder was doped with 1 wt % Sr (Sr‐HA) and 1 wt % Mg (Mg‐HA), heat treated at 800°C for 6 h and then used for plasma spray coating. X‐ray diffraction (XRD) and Fourier transformed infrared spectroscopic (FTIR) analysis indicated that the coatings were primarily composed of phase pure crystalline HA. When compared to undoped HA coating, physical properties such as microstructure, grain size, and adhesive bond strength of the doped HA coatings did not change significantly. Microstructure of the coatings showed coherency in the structure with an average grain size of 200–280 μm HA particles, where each of the HA grains consisted of 20–30 nm sized particles. An average adhesive bond strength of 17 MPa ensured sufficient mechanical strength of the coatings. A chemistry dependent improvement in bone cell‐coating interaction was noticed for doped coatings although it had minimal effect on physical properties of the coatings. In vitro cell–materials interactions using human fetal osteoblasts (hFOB) showed better cell attachment and proliferation on Sr‐HA coatings compared to HA or Mg‐HA coatings. Presence of Sr in the coating also stimulated hFOB cell differentiation and alkaline phosphatase (ALP) expression. Improvement in bioactivity of Sr doped HA coatings on Ti without compromising its mechanical properties makes it an excellent material of choice for coated implant. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Serum 25-hydroxyvitamin D and clinical fracture risk in a multiethnic cohort of women: The women's health initiative (WHI)
Authors: Cauley Jane A , Danielson Michelle E , Boudreau Robert , Barbour Kamil E , Horwitz Mara J , Bauer Douglas C , Ensrud Kristine E , Manson JoAnn E , Wactawski-Wende Jean , Shikany James M , Jackson Rebecca D
Published: June 2011

Low 25-hydroxyvitamin D [25(OH)D] levels have been linked to hip fracture in white women. To study the association of 25(OH)D with risk of fracture in multiethnic women, we performed a nested case-control study within the prospective Women's Health Initiative (WHI) Observational Study. Incident fractures were identified in 381 black, 192 Hispanic, 113 Asian, and 46 Native American women over an average of 8.6 years. A random sample of 400 white women who fractured was chosen. One control individual was selected per case and matched on age, race/ethnicity, and blood draw date. 25(OH)D, parathyroid hormone, and vitamin D–binding protein (DBP) were measured in fasting baseline serum. Conditional logistic regression models were used to calculate the odds ratio (OR) and 95% CI. In multivariable models, higher 25(OH)D levels compared with levels less than 20 ng/mL were associated with a lower risk of fracture in white women (20 to <30 ng/mL: OR = 0.82, 95% CI 0.58–1.16; ≤30.0 ng/mL: OR = 0.56, 95% CI 0.35–0.90; p trend = 0.02). In contrast, higher 25(OH)D (≥20 ng/mL) compared with levels less than 20 ng/mL were associated with a higher risk of fracture in black women (OR = 1.45, 95% CI 1.06–1.98; p trend = 0.043). Higher 25(OH)D (≥30.0 ng/mL) was associated with higher fracture risk in Asian women after adjusting for DBP (OR = 2.78, 95% CI 0.99–7.80; p trend = 0.04). There was no association between 25(OH)D and fracture in Hispanic or Native American women. Our results suggest divergent associations between 25(OH)D and fracture by race/ethnicity. The optimal level of 25(OH)D for skeletal health may differ in white and black women. © 2011 American Society for Bone and Mineral Research
Intermittent PTH(1–84) is osteoanabolic but not osteoangiogenic and relocates bone marrow blood vessels closer to bone-forming sites
Authors: Prisby Rhonda , Guignandon Alain , Vanden-Bossche Arnaud , Mac-Way Fabrice , Linossier Marie-Thérèse , Thomas Mireille , Laroche Norbert , Malaval Luc , Langer Max , Peter Zoltz-Andrei , Peyrin Françoise , Vico Laurence , Lafage-Proust Marie-Hélène
Published: June 2011

Intermittent parathyroid hormone (PTH) is anabolic for bone. Our aims were to determine (1) whether PTH stimulates bone angiogenesis and (2) whether vascular endothelial growth factor (VEGF A) mediates PTH-induced bone accrual. Male Wistar rats were given PTH(1–84) daily, and trabecular bone mass increased 150% and 92% after 30 and 15 days, respectively. The vascular system was contrasted to image and quantify bone vessels with synchrotron radiation microtomography and histology. Surprisingly, bone vessel number was reduced by approximately 25% and approximately 40% on days 30 and 15, respectively. PTH redistributed the smaller vessels closer to bone-formation sites. VEGF A mRNA expression in bone was increased 2 and 6 hours after a single dose of PTH and returned to baseline by 24 hours. Moreover, anti-VEGF antibody administration (1) blunted the PTH-induced increase in bone mass and remodeling parameters, (2) prevented the relocation of bone vessels closer to bone-forming sites, and (3) inhibited the PTH-induced increase in mRNA of neuropilin 1 and 2, two VEGF coreceptors associated with vascular development and function. In conclusion, PTH(1–84) is osteoanabolic through VEGF-related mechanism(s). Further, PTH spatially relocates blood vessels closer to sites of new bone formation, which may provide a microenvironment favorable for growth. © 2011 American Society for Bone and Mineral Research
Molecular modeling study of checkpoint kinase 1 inhibitors by multiple docking strategies and prime/MM–GBSA calculation
Authors: Du Juan , Sun Huijun , Xi Lili , Li Jiazhong , Yang Ying , Liu Huanxiang , Yao Xiaojun
Published: June 2011

Developing chemicals that inhibit checkpoint kinase 1 (Chk1) is a promising adjuvant therapeutic to improve the efficacy and selectivity of DNA‐targeting agents. Reliable prediction of binding‐free energy and binding affinity of Chk1 inhibitors can provide a guide for rational drug design. In this study, multiple docking strategies and Prime/Molecular Mechanics Generalized Born Surface Area (Prime/MM‐GBSA) calculation were applied to predict the binding mode and free energy for a series of benzoisoquinolinones as Chk1 inhibitors. Reliable docking results were obtained using induced‐fit docking and quantum mechanics/molecular mechanics (QM/MM) docking, which showed superior performance on both ligand binding pose and docking score accuracy to the rigid‐receptor docking. Then, the Prime/MM–GBSA method based on the docking complex was used to predict the binding‐free energy. The combined use of QM/MM docking and Prime/MM–GBSA method could give a high correlation between the predicted binding‐free energy and experimentally determined pIC50. The molecular docking combined with Prime/MM–GBSA simulation can not only be used to rapidly and accurately predict the binding‐free energy of novel Chk1 inhibitors but also provide a novel strategy for lead discovery and optimization targeting Chk1. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
The effect of polarization on multiple hydrogen‐bond formation in models of self‐assembling materials
Authors: Chen Yung‐Fou , Dannenberg J. J.
Published: June 2011

We report density functional theory calculations at the B3LYP/D95(d,p) level on several different cyclic H‐bonding dimers, where the monomers of each are connected by a pair of NH···OC H‐bonding interactions, and the H‐bonding donors and acceptors on each monomer are separated by polarizable spacers. Depending on the structures, the individual H‐bonds vary in strength (enthalpy) by over a factor of four, from 2.41 to 10.99 kcal/mol. We attribute most of the variation in interaction energies to differences in the extent of polarization due to each of the H‐bonds, which can either combine constructively or destructively. The dipole–dipole interactions between the pair of H‐bonds also contribute somewhat to the relative stabilities. The relevance of these results to the design of self‐assembling materials is discussed. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Catalytic degradation of oxygenates in Fischer–Tropsch aqueous phase effluents to fuel gas via hydrodeoxygenation over Ru/AC catalyst
Authors: Chen Lungang , Zhu Yulei , Zheng Hongyan , Zhang Chenghua , Zhang Bin , Li Yongwang
Published: June 2011

BACKGROUND: Aqueous phase Fischer–Tropsch (FT) effluents co‐produced with hydrocarbons in the FT process contain various water‐soluble oxygenates, e.g. carboxylic acids, alcohols. Purification of the FT aqueous phase is important from the viewpoint of effective resource utilization and environmental stewardship. In this work, an aqueous‐phase hydrodeoxygenation process was investigated for the degradation of FT aqueous phases.

RESULTS: The Ru/AC catalyst was determined to be the most active catalyst. The key parameters, i.e. temperature, pressure, weight hourly space velocity and Ru loading, were comprehensively optimized. Under optimal conditions, ca 98% of the oxygenates were converted to C1∼C6 alkanes. The degraded water had no odour, a neutral pH, and as low as 1000 mg L−1 chemical oxygen demand. The Ru/AC catalyst exhibited long‐term stability (1300 h) and no ruthenium leaching. A reaction pathway is proposed for this process in which the carboxylic acids are hydrogenated to alcohols via the formation of aldehydes. Alcohols and aldehydes are then converted to methane and alkanes of one carbon atom less than the substrate through CC bond cleavage.

CONCLUSIONS: This process is effective for treating FT aqueous phase effluent, and holds great promise for industrial applications due to its high efficiency, simplicity and stability. Copyright © 2011 Society of Chemical Industry
Therapeutic ultrasound promotes plasmid DNA uptake by clathrin‐mediated endocytosis
Authors: de Paula Daisy Maria Bentes , Valero‐Lapchik Valderez Bastos , Paredes‐Gamero Edgar Julian , Han Sang Won
Published: June 2011

Background

Ultrasound (US) has been widely used to improve the efficiency of nonviral vector transfection. The mechanism of plasmid uptake is usually attributed to sonoporation, although there is not clear evidence for this attribution. Based on our previous results, we hypothesized that other mechanisms, such as endocytosis, could be involved in this process.

Methods

NIH3T3 cells were transfected with plasmid vector pEGFP‐N3 (4.7 kb) using a therapeutic US without microbubbles. Bioeffects such as calcium influx, reactive oxygen species (ROS) generation and membrane potential alterations were accessed with fluorescent dyes in real‐time by confocal microscopy after US insonation. Localization of labeled plasmid DNA in cells was also monitored with endocytosis markers using an immunofluorescence assay.

Results

US at 2 W/cm2 with a duty‐cycle of 20% for 30 s resulted in approximately 40% transfection efficiency but, at 1 W/cm2, resulted in a very low level of transfection. Both the production of ROS and calcium influx were augmented during the insonation, although they were stopped soon after turning off US, with the exception of calcium influx with 1 W/cm2. US also changed the cell membrane potential to the hyperpolarization state, which returned to the normal state soon after insonation. Labeled plasmids DNA could be co‐localized with clathrin‐mediated endocytosis marker but not with caveolin‐1.

Conclusions

The present data indicate that plasmid DNA uptake promoted by US should occur via clathrin‐mediated endocytosis. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis and structure of substituted 5‐phenoxy‐1,2,4‐dithiazole‐3‐ones
Authors: Ponomarov Oleksandr , Padělková Zdeňka , Hanusek Jiří
Published: June 2011

Seven new substituted 5‐phenoxy‐1,2,4‐dithiazole‐3‐ones were prepared in modest yield (53–76%) from corresponding O‐phenyl thiocarbamates and chlorocarbonylsulfenyl chloride in dry ether at −10 °C. All of the compounds were characterized by NMR and elemental analysis and some of them by X‐ray diffraction. Preliminary kinetic measurements showed that the parent 5‐phenoxy‐1,2,4‐dithiazole‐3‐one is a very efficient sulfurizing agent toward triphenyl phosphite. J. Heterocyclic Chem., (2011)
Trajectory compensation in an autoresonant trap mass spectrometer
Authors: Ermakov A. V. , Hinch B. J.
Published: July 2011

The auto‐resonant trap mass spectrometer, ART‐MS, utilizes electrostatic ion trapping within an anharmonic potential well. Ions are detected after mass selective trap ejection with auto‐resonant driving employing only low‐power rf electronics. We identify the major limiting factor in the mass resolution of these instruments. Whilst keeping in the spirit of maintaining a rapid scan rate, low cost, lightweight instrument, with minimal required machining tolerances, we introduce a method for much improving the mass resolutions of an ART‐MS. The addition of two electrodes has enabled an improvement in the mass resolution by a factor of ∼4. The scheme significantly reduces the effects of a finite sized trap and compensates for the influence of radial variation in natural oscillating frequencies within the trap. Compensation can be implemented with a wide range of designs and is not limited by the size of the trap. Copyright © 2011 John Wiley & Sons, Ltd.
Lithium protects against oxidative stress‐mediated cell death in α‐synuclein‐overexpressing in vitro and in vivo models of Parkinson's disease
Authors: Kim Yong‐Hwan , Rane Anand , Lussier Stephanie , Andersen Julie K.
Published: June 2011

Lithium has recently been suggested to have neuroprotective properties in relation to several neurodegenerative diseases. In this study, we examined the potential cytoprotective effect of lithium in preventing oxidative stress‐induced protein accumulation and neuronal cell death in the presence of increased α‐synuclein levels in vitro and in vivo. Specifically, lithium administration was found to protect against cell death in a hydrogen peroxide‐treated, stable α‐synuclein‐enhanced green fluorescent protein (EGFP)‐overexpressing dopaminergic N27 cell line. Lithium feeding (0.255% lithium chloride) of 9‐month‐old pan‐neuronal α‐synuclein transgenic mice over a 3‐month period was also sufficient to prevent accumulation of oxidized/nitrated α‐synuclein as a consequence of chronic paraquat/maneb administration in multiple brain regions, including the glomerular layer, mitral cells, and the granule cell layer of the olfactory bulb (OB), striatum, substantia nigra pars compacta (SNpc) and Purkinje cells of the cerebellum. Lithium not only prevented α‐synuclein‐mediated protein accumulation/aggregation in these brain regions but also protected neuronal cells including mitral cells and dopaminergic SNpc neurons against oxidative stress‐induced neurodegeneration. These results suggest that lithium can prevent both α‐synuclein accumulation and neurodegeneration in an animal model of PD, suggesting that this drug, already FDA‐approved for use in bipolar disorder, may constitute a novel therapy for another human disease. © 2011 Wiley‐Liss, Inc.
Characterization of an iron smelting slag from Zimbabwe by Raman microscopy and electron beam analysis
Authors: Muralha Vânia S. F. , Rehren Thilo , Clark Robin J. H.
Published: June 2011

A sample of archaeological iron slag from Northern Zimbabwe was characterised by Raman microscopy (RM) and electron beam analysis (EBA). The phases identified in a slag found at an ironmaking site not only reflect the chemical composition of the slag but can also provide crucial information regarding the reconstruction and interpretation of the metallurgical operations, such as the prevailing redox conditions in a furnace at the time of cooling. Free iron oxides, such as haematite, magnetite and wüstite, are important indicators of these redox conditions. But while classical techniques of phase identification can be used to identify the different iron oxides, they cannot distinguish between dissimilar oxidation states due to their non‐stoichiometric nature, and also the effect of substituting elements in iron oxides. RM proved invaluable in both respects. By combining the results provided by RM and EBA, it was possible to identify (1) the free iron oxides, haematite and magnetite in the original ore, and magnetite and wüstite in the slag, (2) oxidised magnetite and wüstite, characterized by a shift to higher wavenumbers of their intense characteristic Raman bands and (3) Al3+‐substituted magnetite and a solid solution between magnetite and hercynite (FeAl2O4). This pilot study aims to develop a model that enables close identification of the redox conditions by analysing the free iron oxides from a variety of smelting processes. It is hoped that this will provide an independent and quantifiable criterion to distinguish smithing slags (more oxidising) from smelting slags (more reducing), and to understand better the actual smelting process that transforms highly oxidised iron ore to fully reduced iron metal. Copyright © 2011 John Wiley & Sons, Ltd.
Conformational, vibrational, and structural studies of 2,2,3,3,3‐pentafluoropropylamine from Raman and infrared spectra of gas, liquid, xenon solutions, and solid supported by ab initio calculations
Authors: Guirgis, Gamil A. , Darkhalil, Ikhlas D. , Klaassen, Joshua J. , Ganguly, Arindam , Wyatt, Justin K. , Durig James R.
Published: June 2011

The Raman and infrared spectra (3500–50 cm−1) of the gas, liquid or solution, and solid were recorded of 2,2,3,3,3‐pentafluoropropylamine (CF3CF2CH2NH2) and the ND2 isotopomer. Variable temperature (−55 to − 100 °C) studies of the infrared spectra (3600–400 cm−1) of samples dissolved in liquid xenon have been carried out. From these data, two of the five possible conformers have been identified and their relative stabilities obtained. The enthalpy difference was determined between the more stable Tt conformer and the less stable Tg form to be 280 ± 14 cm−1 (3.35 ± 0.17 kJ/mol). The first indicator is the NCCC dihedral angle (G = gauche or T = trans), and the second one (g = gauche or t = trans) is the relative position of the lone pair of electrons on nitrogen with respect to the β‐carbon. The percentage of the Tg conformer at ambient temperature is estimated to be 34 ± 2%. The conformational stabilities have been predicted from ab initio calculations utilizing several different basis sets up to aug‐cc‐pVTZ for both MP2(full) and density functional theory calculations by the B3LYP method. Vibrational assignments have been provided for most of the observed bands for both isotopomers, supported by MP2(full)/6‐31G(d) ab initio calculations to predict the harmonic force fields, wavenumbers, infrared intensities, Raman activities, and depolarization ratios for both conformers. Estimated r0 structural parameters were obtained from adjusted MP2(full)/6‐311 + G(d,p) calculations. The results are discussed and compared with the corresponding properties of some related molecules. Copyright © 2011 John Wiley & Sons, Ltd.
Hydrogen‐bonding interactions in fully deuterated α‐glycine at high pressures
Authors: Sharma Bharat Bhooshan , Murli Chitra , Chitra R. , Sharma Surinder M.
Published: June 2011

Recent spectroscopic investigations of various amino acids report intriguing high‐pressure and low‐temperature behavior of NH3+ groups and their influence on various hydrogen bonds in the system. In particular, the variation of the intensity of NH3+ torsional mode at different temperatures and pressures has received much attention. We report here the first in situ Raman investigations of fully deuterated α‐glycine up to ∼20 GPa. The discontinuous changes in COO− and ND3+ modes across ∼3 GPa indicate subtle structural rearrangements in fully deuterated α‐glycine. The decrease in the intensity of ND3+ torsional mode is found to be similar to that of undeuterated α‐glycine. The pressure‐induced stiffening of ND and CD2 stretching modes are discussed in the context of changes in the hydrogen‐bonding interactions. Copyright © 2011 John Wiley & Sons, Ltd.
Two‐dimensional standoff Raman measurements of distant samples
Authors: Porter John N. , Helsley Charles E. , Sharma Shiv K. , Misra Anupam K. , Bates David E. , Lienert Barry R.
Published: June 2011

A scanning standoff Raman spectroscopy system has been developed to measure the molecular species of distant samples in two dimensions. Computer software is used to control the scanner pan and tilt angles, and Raman measurements are collected of the distant sample area in an x–y grid pattern. The Raman spectra at each grid point are measured and processed to obtain an image of the distant surface composition. The ability to provide interpolated images of distant molecular species is illustrated. Copyright © 2011 John Wiley & Sons, Ltd.
Triple‐resonant two‐phonon Raman scattering in graphene
Authors: Kupčić I.
Published: June 2011

The triple‐resonant (TR) second‐order Raman scattering mechanism in graphene is re‐examined. It is shown that the magnitude of the TR contribution to the photon‐G′ mode coupling function in graphene is one order of magnitude larger than the widely accepted two‐resonant coupling. Enhancement of the order of 100 in the Raman intensity, with respect to the usual double‐resonant model, is found for the G′ band in graphene, and is expected in the related sp2‐based carbon materials, as well. Copyright © 2011 John Wiley & Sons, Ltd.
Testing of Raman spectroscopy as a non‐invasive tool for the investigation of glass‐protected miniature portraits
Authors: Mancini Diana , Tournié Aurélie , Caggiani Maria‐Cristina , Colomban Philippe
Published: July 2011

Six French miniature portraits on ivory and paper dating back to the 18th to 19th centuries have been studied by Raman spectroscopy. The miniatures have been investigated through their protective glass cover using different operating conditions: various laser wavelengths (1064, 785 and 532 nm), spectrometers (fixed and mobile) and objectives (10× to 200×). The results obtained for black (carbon), grey (carbon + chalk), red (lead oxide, vermillion), blue (Prussian or phthalocyanine blue), green (emerald or Paris green) and white (lead white) pigments are presented. The consistency of the period of use of the pigments with the proposed dating for each artwork is evaluated. Attention is paid to the analysis of the ivory substrates (assigned to Asian elephant ivory) and to the protective glass. Copyright © 2011 John Wiley & Sons, Ltd.
Zincon as resonance Raman probe for quantitative evaluation of proteins
Authors: Chen Lei , Park Yeonju , Seo Hyeongkuyn , Hong Wonjin , Jung Young Mee , Zhao Bing
Published: June 2011

This paper demonstrates the potential of using a resonance Raman (RR) based method for the quantitative evaluation of protein concentrations. This method was applied to determine the concentration of bovine serum albumin (BSA) protein using zincon. In the protein–zincon liquid mixture, the number of unbound zincon molecules decreased markedly as the protein concentration increased because of the high affinity of zincon for proteins. We successfully detected very low concentrations of BSA (∼1 ng/ml) using this method, which demonstrates its great potential for the detection of proteins over a much wider range of concentrations in proteomic studies. This new RR‐based method allows the detection of proteins in lower concentration than with the UV–vis‐based and other protein assays commonly used in biochemical laboratories. Copyright © 2011 John Wiley & Sons, Ltd.
A modified technique for end‐to‐side pancreaticojejunostomy by purse‐string suture
Authors: Jiang Chunping , Wang Meng , Xu Qingxiang , Wu Xingyu , Yu Decai , Ding Yitao
Published: June 2011

Backgroud

Pancreatic fistula is a leading cause of morbidity and mortality after pancreaticoduodenectomy. We designed a modified technique, by which the pancreatic stump was invaginated into the jejunal loop by purse‐string suture.

Methods

From June 2008, 18 cases of patients were performed with this modified technique, and the morbidity and mortality were calculated.

Results

All cases recovered well from pancreaticoduodenectomy, and none of them occured pancreatic fistula. The complications included: hemorrhage, wound infection, pulmonary infection, and ascite.

Conclusions

Invagination anatomosis by purse‐string suture could be performed safely and reduced the leakage rate of pancreaticojejunostomy. J. Surg. Oncol. 2011; 104:852–856. © 2011 Wiley Periodicals, Inc.
Extensive screening for primary tumor is redundant in melanoma of unknown primary
Authors: Tos Tina , Klyver Helle , Drzewiecki Krzysztof T.
Published: June 2011

For decades, patients in our institution with metastastic melanoma of unknown primary have been subjected to extensive examinations in search of the primary tumor. This retrospective study questions the results, and thus the feasibility of these examinations. Of 103 patients diagnosed with unknown primary tumor during the period 1986–2006, 39 (38%) presented primarily with a cutaneous or a subcutaneous metastasis, and 63 (61%) with a lymph node metastasis. One patient presented with a bone metastasis (1%). Eighty‐seven patients (84%) were examined by an ophthalmologist. A choroidal melanoma was suspected as the primary tumor in one patient. Eighty‐four patients (82%) were examined by an oto‐rhino‐laryngologist, whereby no primary tumor was found. Ninety‐five patients (92%) were examined by sigmoideoscopy/rectoscopy. No primary tumor was found. Of the 36 women, 32 had a gynecological examination (89%), revealing no primary tumor. We conclude, that only one possible (but not verified) primary tumor was disclosed by various specialists examinations of 103 patients referred with the diagnosis metastatic melanoma with no primary tumor. Special screenings can thus be considered as redundant. Thus, for patients referred with metastastic melanoma of unknown primary, we recommend that a detailed history is obtained, and a standard physical examination performed, in addition to a histopathological review and CT/PET for staging. J. Surg. Oncol. 2011; 104:724–727. © 2011 Wiley Periodicals, Inc.
More than one pulmonary resections or combined lung‐liver resection in 79 patients with metastatic colorectal carcinoma
Authors: Jarabo Jose R. , Fernández Elena , Calatayud Joaquín , Gómez Ana M. , Fernández Cristina , Torres Antonio J. , Hernando Florentino
Published: June 2011

Background

The way to select patients who will benefit from surgical resection of pulmonary metastases of colorectal carcinoma (CRC) remains unclear.

Methods

We analyze overall survival and potential prognostic factors in 101 pulmonary resections of CRC metastases in 79 patients, focusing on cases with repeated pulmonary resection or with hepatic metastasectomy.

Results

Number of pathological pulmonary metastases was higher than that of preoperatively suspected pulmonary nodules in 18% of the resections. Morbidity rate was 16.5%. There was no mortality. Five‐year survival rates from the resection of the CRC and from the first pulmonary metastasectomy were 74.6% and 53.3%, respectively. Prognosis did not decrease in patients with history of hepatic metastasectomy or in those in which repeated pulmonary resection was performed. Age ≥70, preoperative carcinoembrionary antigen (CEA) ≥5 ng/dl and mediastinal lymph node involvement entailed worse prognosis. Pathological lymph node involvement and age were shown as independent prognostic factors in the multivariate analysis.

Conclusions

Resection of pulmonary metastases of CRC is a safe procedure, with 5‐year survival rates over 50%. History of resected hepatic metastases or needs for more than one pulmonary resection do not seem to decrease survival rates. Only lymph node involvement and age seem to be clearly associated to worse prognosis. J. Surg. Oncol. 2011; 104:781–786. © 2011 Wiley Periodicals, Inc.
Role of the Lymph node ratio in pancreatic ductal adenocarcinoma. Impact on patient stratification and prognosis
Authors: La Torre Marco , Cavallini Marco , Ramacciato Giovanni , Cosenza Giulia , del Monte Simone Rossi , Nigri Giuseppe , Ferri Mario , Mercantini Paolo , Ziparo Vincenzo
Published: June 2011

Background

Survival after resection of pancreatic adenocarcinoma is poor. Several prognostic factors such as the status of the resection margin, lymph node status, or tumor grading have been identified. Aim of the study was to evaluate the prognostic significance of the lymph node ratio (LNR) for resected pancreatic ductal adenocarcinoma.

Materials and Methods

Data were collected from 101 patients who had undergone pancreatoduodenectomy for pancreatic ductal adenocarcinoma. Patients were divided into four groups according to the absolute LNR (0, 0–0.199, 0.2–0.399, >0.4). Kaplan–Meier and Cox proportional hazard models were used to evaluate the prognostic effect.

Results

The actuarial 3‐ and 5‐year survival rates were 32 and 17%, respectively. The median survival was 19 months. Patients with LNR 0/0–0.199/0.2–0.399/>0.4 survived 40.2/30.5/18.1, and 13.6 months, respectively (P = 0.001). At the multivariate analysis, lymph node status was not found to be a significant prognostic factor; on the contrary LNR >0.2 (P = 0.007), positive resection margin (P = 0.001), and grading (P = 0.05) were significantly related to survival.

Conclusion

LNR is a more powerful predictor of survival than the lymph node status in patients undergoing pancreaticoduodenectomy for ductal adenocarcinoma. J. Surg. Oncol. 2011; 104:629–633. © 2011 Wiley Periodicals, Inc.
Determination of bisphenol‐A levels in human amniotic fluid samples by liquid chromatography coupled with mass spectrometry
Authors: Chen Mei , Edlow Andrea G. , Lin Tao , Smith Nicole A. , McElrath Thomas F. , Lu Chensheng
Published: June 2011

Bisphenol A (BPA) is one of the environmental endocrine‐disrupting chemicals used widely in common consumer products. There is an increasing concern about human exposure to BPA, particularly in fetuses, due to the potential adverse effects related to the estrogenic activity of BPA. In assessing environmental exposure to BPA, it is essential to have a sensitive, accurate, and specific analytical method, particularly for low BPA levels in complex sample matrices. In this study, we developed and validated an accurate, sensitive, and robust liquid chromatography–mass spectrometry (LC‐MS) method for determining the BPA concentrations in human amniotic fluid (AF). In this method, BPA and the internal standards 13C12‐BPA were extracted from 500 μL of human AF using solid‐phase extraction. Calibration curves were linear over a concentration range of 0.3–100 ng/mL for BPA. The analytes were quantitatively determined using LC‐MS operated in a negative electrospray ionization selected ion monitoring mode. This validated method has been used successfully in the clinical sample analysis of BPA in second‐trimester AF specimens.
Reproduction of northern spotted owls: The role of local weather and regional climate
Authors: Glenn Elizabeth M. , Anthony Robert G. , Forsman Eric D. , Olson Gail S.
Published: June 2011

We examined associations between annual reproduction and climate for 6 populations of individually marked northern spotted owls (Strix occidentalis caurina) in Washington and Oregon. We used an information‐theoretical approach and mixed models to evaluate statistical models representing a priori hypotheses about the effects of weather and climate on reproduction. Reproduction was higher for adult than subadult owls and declined as the proportion of spotted owl territories with barred owl (Strix varia) detections increased. Similar to other spotted owl studies, we found that reproduction was negatively associated with cold, wet winters and nesting seasons at 3 of 6 study areas. In addition, we identified new relationships between reproduction, annual precipitation, storms, and regional climate cycles. For 3 of 6 areas, we found a quadratic relation between precipitation (rain and snow) and reproduction, with the number of young fledged per pair per year declining as precipitation in the previous year deviated from average levels. A meta‐analysis conducted across all 6 areas indicated that reproduction at the regional level had a quadratic association with total winter snowfall in the preceding winter and was positively related to temperatures during the previous summer and fall. The amount of annual variation in reproduction accounted for by weather and climate varied widely across the 6 areas (4–79%), whereas variation in weather and climate across owl territories accounted for little of the spatial variation in reproduction (0–4%). Our results suggest that across the range of the species climate factors affecting prey abundance may have a greater effect on reproduction than direct effects of weather on nestlings. © 2011 The Wildlife Society.
Highly Selective Uptake and Release of Charged Molecules by pH‐Responsive Polydopamine Microcapsules
Authors: Liu Qinze , Yu Bo , Ye Weichun , Zhou Feng
Published: June 2011

A systematic study of the permeation of small molecules through Pdop microcapsules is reported. The zwitterionic Pdop microcapsules are prepared by oxidative polymerization of dopamine on polystyrene microspheres followed by core removal with THF. Rhodamine 6G, methyl orange and alizarin red are chosen as differently charged probing dyes. The loading amount is affected by pH and dye concentration. Highly selective and unidirectional uptake and release of charged molecules through Pdop microcapsules can be achieved by controlling pH value: at low pH, the Pdop particles incorporate cationic dye (rhodamine 6G); at high pH, they incorporate anionic dyes (methyl orange and alizarin red). In each case, the uptake is highly selective.

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Amphiphilic Block Copolymers from a Direct and One‐pot RAFT Synthesis in Water
Authors: Chaduc Isabelle , Zhang Wenjing , Rieger Jutta , Lansalot Muriel , D'Agosto Franck , Charleux Bernadette
Published: June 2011

The syntheses of amphiphilic block copolymers are successfully performed in water by chain extension of hydrophilic macromolecules with styrene at 80 °C. The employed strategy is a one‐pot procedure in which poly(acrylic acid), poly(methacrylic acid) or poly(methacrylic acid‐co‐poly(ethylene oxide) methyl ether methacrylate) macroRAFTs are first formed in water using 4‐cyano‐4‐thiothiopropylsulfanyl pentanoic acid (CTPPA) as a chain transfer agent. The resulting macroRAFTs are then directly used without further purification for the RAFT polymerization of styrene in water in the same reactor. This simple and straightforward strategy leads to a very good control of the resulting amphiphilic block copolymers.

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