bluuebunny/crossref_metadata_2025 huggingface dataset:
Genotypic characterization of non starter lactic acid bacteria involved in the ripening of artisanal Bitto PDO cheese
Authors: Colombo Francesca , Borgo Francesca , Fortina Maria Grazia
Published: October 2009

Bitto of Valchiavenna, an artisanal Italian cheese produced without the addition of any starter cultures, has been attributed a protected designation origin (PDO) cheese, but the strain composition of the natural microbial population colonizing this traditional dairy product is still unknown. To obtain preliminary information on the non starter lactic acid bacteria involved in its ripening, a total of 136 NSLAB isolates, randomly selected from MRS and M17 agar plates, were collected from three different cheese samples after 120 days of ripening. The new isolates were identified by combining PCR 16S–23S rDNA spacer analyses, partial 16S rRNA gene sequencing, species‐specific probes and colony hybridization. Eighty‐two isolates, representing 60% of the total strains selected, were homofermentative cocci: 83% of them were enterococci, with Enterococcus durans being the predominant species found. Pediococcus spp. were also isolated, together with strains of Streptococcus thermophilus. Within lactobacilli, 57% of the isolates were identified as Lactobacillus paracasei; Lact. curvatus, Lact. plantarum, Lact. fermentum, were present in a lower amount. The isolates were differentiated at strain‐level by Rep‐PCR analysis. This is the first effort to microbiological characterization of Valchiavenna's Bitto; the results suggest the possibility of preserving the wild bacterial population in order to protect the typical organoleptic characteristics of this traditional raw milk cheese and to select new strains for the dairy industry. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Co‐production of γ ‐glutamylcysteine and glutathione by mutant strain Saccharomyces cerevisiae FC‐3 and its kinetic analysis
Authors: Chen When‐Chang , Huang Fu‐Kuo , Cheng Shu‐Chuan , Tsai Feng‐Yuan , Lin Chung‐Liang
Published: October 2009

Co‐production of γ ‐glutamylcysteine (γ ‐GC) and glutathione (GSH) by a novel mutant strain Saccharomyces cerevisiae FC‐3 and its kinetic analysis were investigated. The strain could produce γ ‐GC and GSH with high yields (4.22 and 14.3 mg/g‐DCW, respectively) in batch submerged cultures. Effects of medium components and cultivation conditions on cell growth and the contents of intracellular γ ‐GC and GSH were examined. Results show that 2% (w/v) sucrose and 2.5% (w/v) yeast extract are the best carbon and nitrogen sources, respectively, and supplement of three amino acids (glycine, cysteine and glutamate), each at 0.08% (w/v), in the medium could enhance γ ‐GC and GSH production. In addition, optimal operating conditions are at the initial pH value of 7.0, 30 °C and 200 rev/min. Moreover, results obtained from kinetic analyses reveal that γ ‐GC production is mixed‐type growth associated, but GSH production is growth‐associated. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of new biosurfactant produced by Trichosporon montevideense CLOA 72 isolated from dairy industry effluents
Authors: Monteiro Andrea S. , Coutinho Joana O. P. A. , Júnior Ary C. , Rosa Carlos A. , Siqueira Ezequias P. , Santos Vera L.
Published: October 2009

The yeast strain CLOA 72 isolated from the effluent of a dairy industry in Brazil and identified as Trichosporon montevideense, was able to grow and produce a glycolipid biosurfactant when cultured on a mineral medium (MM) with sunflower oil as the carbon source. Biosurfactant production was partially growth‐associated and maximal emulsification activity was observed at 144 h of cultivation (78.92%). The biosurfactant purified by precipitation with ethanol showed 78.66% emulsifying activity when used in concentrations above 4.5 mg/ml and was able to reduce the surface tension of water to values below 44.9 mN/m. The critical micellar concentration (CMC) was found to be 2.2 mg/ml. The highest emulsifying activity (E24) has been observed with vegetable oils, toluene, kerosene, isooctane, cyclohexane, hexane, diesel oil and hexadecane as compared to mineral oil and oleic acid. The biosurfactant also showed good stability during exposure to 100 °C for different periods of time (10 to 60 min), to high salinity (30% of NaCl, KCl and NaHCO3), and to a wide range of pH values (1–10). The biosurfactant purified by gel filtration chromatography is a glycolipid, with lipid portion containing 16.03% (9Z)‐octadec‐9‐enoic acid, 14.92% hexadecanoic acid, and 9.63% (E) octadec‐9‐enoic acid and the carbohydrate portion containing mannose (35.29%), xylose (41.99%), arabinose (17.47%), and glucose (5.25%). (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Low‐intensity pulsed ultrasound (LIPUS) increases the articular cartilage type II collagen in a rat osteoarthritis model
Authors: Naito Kiyohito , Watari Taiji , Muta Tomoya , Furuhata Atsushi , Iwase Hideaki , Igarashi Mamoru , Kurosawa Hisashi , Nagaoka Isao , Kaneko Kazuo
Published: October 2009

In this study, the effect of low‐intensity pulsed ultrasound (LIPUS) on cartilage was evaluated in a rat osteoarthritis (OA) model using serum biomarkers such as CTX‐II (type II collagen degradation) and CPII (type II collagen synthesis) as well as histological criteria (Mankin score and immunohistochemical type II collagen staining). OA was surgically induced in the knee joint of rats by anterior cruciate/medial collateral ligament transection and medial meniscus resection (ACLT + MMx). Animals were divided into three groups: sham‐operated group (Sham), ACLT + MMx group without LIPUS (−LIPUS), and ACLT + MMx group with LIPUS (+LIPUS; 30 mW/cm2, 20 min/day for 28 days). CTX‐II levels were elevated in both −LIPUS and +LIPUS groups compared to that in the Sham group after the operation, but there was no significant difference between +LIPUS and −LIPUS groups, suggesting that LIPUS does not affect the degradation of type II collagen in this model. In contrast, CPII was significantly increased in +LIPUS group compared to −LIPUS and Sham. Moreover, histological damage on the cartilage (Mankin score) was ameliorated by LIPUS, and type II collagen was immunohistochemically increased by LIPUS in the cartilage of an OA model. Of interest, mRNA expression of type II collagen was enhanced by LIPUS in chondrocytes. Together these observations suggest that LIPUS is likely to increase the type II collagen synthesis in articular cartilage, possibly via the activation of chondrocytes and induction of type II collagen mRNA expression, thereby exhibiting chondroprotective action in a rat OA model. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:361–369, 2010
Titanium uptake, induction of RANK‐L expression, and enhanced proliferation of human T‐lymphocytes
Authors: Cadosch Dieter , Sutanto Michael , Chan Erwin , Mhawi Amir , Gautschi Oliver P. , von Katterfeld Brilliana , Simmen Hans‐Peter , Filgueira Luis
Published: October 2009

There is increasing evidence that titanium ions are released from orthopedic implants by biocorrosion. The aim of this study was to investigate titanium uptake by human T‐lymphocytes and its effects on phenotype and proliferation. Freshly isolated human nonadherent peripheral blood mononuclear cells (NA‐PBMC), were exposed to TiCl4 [Ti(IV)]. Bioavailability and distribution of Ti(IV) in T‐lymphocytes was determined by energy‐filtered electron microscopy (EFTEM). The effects of Ti(IV) challenge on nonactivated and PHA‐activated cells were assessed by flow cytometric analysis of surface markers, RANK‐L production, and proliferation assays. EFTEM colocalized Ti(IV) with phosphorus in the nucleus, ribosomes, cytoplasmic membranes, and the surface membrane of T‐lymphocytes. Ti(IV) increased significantly the expression of CD69, CCR4, and RANK‐L in a concentration‐dependent manner. Titanium enters T‐lymphocytes through a currently unknown mechanism and binds to phosphorus‐rich cell structures. Titanium influences phenotype and function of T‐lymphocytes, resulting in activation of a CD69+ and CCR4+ T‐lymphocyte population and secretion of RANK‐L. These results strongly suggest the involvement of titanium ions challenged T‐lymphocytes in the complex pathophysiological mechanisms of aseptic loosening of orthopedic implants. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:341–347, 2010
Vibrational spectroscopy and crystal structure analysis of two polymorphs of the di‐amino acid peptide cyclo(L‐Glu‐L‐Glu)
Authors: Mendham Andrew P. , Palmer Rex A. , Potter Brian S. , Dines Trevor J. , Snowden Martin J. , Withnall Robert , Chowdhry Babur Z.
Published: October 2009

Cyclo(L‐Glu‐L‐Glu) has been crystallised in two different polymorphic forms. Both polymorphs are monoclinic, but form 1 is in space group P21 and form 2 is in space group C2. Raman scattering and FT‐IR spectroscopic studies have been conducted for the N,O‐protonated and deuterated derivatives. Raman spectra of orientated single crystals, solid‐state and aqueous solution samples have also been recorded. The different hydrogen‐bonding patterns for the two polymorphs have the greatest effect on vibrational modes with NH and CO stretching character. DFT (B3‐LYP/cc‐pVDZ) calculations of the isolated cyclo(L‐Glu‐L‐Glu) molecule predict that the minimum energy structure, assuming C2 symmetry, has a boat conformation for the diketopiperazine ring with the two L‐Glu side chains being folded above the ring. The calculated geometry is in good agreement with the X‐ray crystallographic structures for both polymorphs. Normal coordinate analysis has facilitated the band assignments for the experimental vibrational spectra. Copyright © 2009 John Wiley & Sons, Ltd.
Crystal structure and phonon modes of ilmenite‐type NaBiO3 investigated by Raman and infrared spectroscopies
Authors: Dias Anderson , Moreira Roberto L.
Published: October 2009

NaBiO3 is an ilmenite‐type compound presenting a trigonal structure. In this work, we have performed optical spectroscopic investigations using Raman scattering and infrared reflectivity for this material. By using group‐theory calculations, it was possible to determine the number of optically active modes. Fitting procedures besides Kramers–Kronig (KK) procedures lead to a consistent collection of phonon modes. The Raman spectrum showed nine active first‐order modes, while the infrared one revealed eight polar phonons, in good agreement with the theoretical predictions. The results allowed us to confirm the R3 (#148) space group for this compound, and to establish a set of active phonons not yet reported in the literature. Copyright © 2009 John Wiley & Sons, Ltd.
Raman microscopy of haidingerite Ca(AsO3OH)·H2O and brassite Mg(AsO3OH)·4H2O
Authors: Frost Ray L. , Bahfenne Silmarilly , Čejka Jiří , Sejkora Jiří , Palmer Sara J. , Škoda Radek
Published: October 2009

Raman spectroscopy has been used to study the arsenate minerals haidingerite Ca(AsO3OH)·H2O and brassite Mg(AsO3OH)·4H2O. Intense Raman bands in the haidingerite spectrum observed at 745 and 855 cm−1 are assigned to the (AsO3OH)2−ν3 antisymmetric stretching and ν1 symmetric stretching vibrational modes. For brassite, two similarly assigned intense bands are found at 809 and 862 cm−1. The observation of multiple Raman bands in the (AsO3OH)2− stretching and bending regions suggests that the arsenate tetrahedrons in the crystal structures of both minerals studied are strongly distorted. Broad Raman bands observed at 2842 cm−1 for haidingerite and 3035 cm−1 for brassite indicate strong hydrogen bonding of water molecules in the structure of these minerals. OH···O hydrogen‐bond lengths were calculated from the Raman spectra based on empirical relations. Copyright © 2009 John Wiley & Sons, Ltd.
Study of asymmetric wavenumber shift of the Fermi doublet ν1 − 2ν2 in the Raman spectrum of liquid carbon disulfide
Authors: Li Dong‐Fei , Jiang Xiu‐Lan , Cao Biao , Li Zuo‐Wei , Gao Shu‐Qin , Zhou Mi , Men Zhi‐Wei , Zhai Nai‐Cui
Published: October 2009

The Raman spectra of liquid carbon disulfide (CS2) diluted with benzene (C6H6) have been measured. By changing the CS2, the concentration, we found an asymmetric wavenumber shift phenomenon. With decreasing concentration of CS2, the position of the ν1 (655 cm−1) band remains practically unchanged, and the 2ν2 (796 cm−1) band shifts toward higher wavenumbers. To interpret this asymmetric wavenumber shift phenomenon of the Fermi doublet ν1 − 2ν2 in the Raman spectra satisfactorily, we propose a modified Bertran model. The values of the Fermi resonance (FR) parameters of CS2 at different concentrations were calculated using the Bertran equations. In addition, we found the fundamental ν2, which should be independent of the FR interaction, shifted to higher wavenumbers as the concentration decreased. This shift was probably driven by the tuning of the FR. Copyright © 2009 John Wiley & Sons, Ltd.
PCR experion automated electrophoresis system to detect Listeria monocytogenes in foods
Authors: Delibato Elisabetta , Gattuso Antonietta , Minucci Angelo , Auricchio Bruna , De Medici Dario , Toti Laura , Castagnola Massimo , Capoluongo Ettore , Gianfranceschi Monica Virginia
Published: October 2009

Listeria monocytogenes is frequently found as a contaminant in raw and ready‐to‐eat foods. The ability of L. monocytogenes to multiply at refrigeration temperatures and to grow in a wide range of pH values is of particular concern for food safety. According to the European Union regulation on microbiological criteria for foodstuffs, L. monocytogenes must be absent in some categories of ready‐to‐eat foods. The standard microbiological method for L. monocytogenes detection in foods (ISO 11290‐1: 1996 (ISO, International Organization for Standardization)) is cost and time consuming. Developments of rapid, cost‐effective and automated diagnostic methods to detect food‐borne pathogens in foods continue to be a major concern for the industry and public health. The aim of this study was the development of a rapid, sensitive and specific molecular detection method for L. monocytogenes. To this purpose, we have applied a capillary electrophoresis method to a PCR protocol (PCR‐EES (EES, experion automated electrophoresis system)) for detecting L. monocytogenes in food. In particular, a microfluidic chip‐based automated electrophoresis system (experion automated electrophoresis system, Bio‐Rad Laboratories, USA) was used for the rapid and automatic analysis of the amplicons. Fifty naturally contaminated samples were analysed with this method and the results were compared with those obtained with ISO method. Moreover, the microfluidic chip‐based automated electrophoresis system was compared with classical gel electrophoresis (PCR‐CGE). The results showed that after 24 h of culture enrichment, the PCR‐EES showed a relative accuracy of 100% with ISO, while using PCR‐CGE decreased it down to 96%. After 48 h of enrichment, both PCR‐EES and PCR‐CGE showed an accuracy of 100% with ISO.
Identifying PTSD personality subtypes in a workplace trauma sample
Authors: Sellbom Martin , Bagby R. Michael
Published: October 2009

The authors sought to identify personality clusters derived from the Minnesota Multiphasic Personality Inventory‐2 (MMPI‐2) Personality Psychopathology Five Scales in a sample of workplace claimants with posttraumatic stress disorder (PTSD). Three clusters—low pathology, internalizing, and externalizing were recovered similar to those obtained by M. W. Miller and colleagues (2003, 2004, 2007) in samples of combat veterans and sexual assault victims. Internalizers and externalizers scored comparably on measures of PTSD symptom severity, general distress, and negative affect. Internalizers were uniquely characterized by anhedonia and depressed mood; externalizers by antisocial behavior, substance abuse, and anger/aggression.
Monitoring interstitial m‐THPC‐PDT in vivo using fluorescence and reflectance spectroscopy
Authors: Kruijt Bastiaan , van der Ploeg‐van den Heuvel Angelique , de Bruijn Henriette S. , Sterenborg Henricus J.C.M. , Amelink Arjen , Robinson Dominic J.
Published: October 2009

Background and Objective

In order to understand the mechanisms of photodynamic therapy (PDT) it is important to monitor parameters during illumination that yield information on deposited PDT dose. The aim of this study is to investigate the possibility of monitoring implicit parameters, such as photobleaching, in addition to monitoring explicit parameters (fluence (rate), oxygenation, photosensitizer concentration) directly or indirectly. These parameters are monitored during PDT without interrupting the therapeutic illumination.

Materials and Methods

Rats were injected with 0.3 mg kg−1 m‐THPC. Sixteen hours after administration the abdominal muscle in rats was irradiated for 1,500 seconds using clinically relevant fluence rates of 50, 100, and 250 mW cm−1 of diffuser length at 652 nm. In addition to the linear diffuser for delivering treatment light, isotropic fiber‐optic probes and fiber‐optic probes for differential path‐length spectroscopy (DPS) were placed on both sides of the muscle to monitor tissue physiological parameters, fluence rate, and fluorescence.

Results

The m‐THPC treatment groups show a decrease in fluence rate throughout PDT of 16%, 19%, and 27% for the 50, 100, and 250 mW cm−1 groups, respectively. Both during and post‐PDT differences in vascular response between treatment groups and animals within the same treatment group are observed. Furthermore we show fluence rate dependent bleaching of m‐THPC up to a measured fluence rate of 100 mW cm−1.

Conclusion

The data presented in this study show the possibility of simultaneously monitoring fluence (rate), fluorescence, hemoglobin oxygen saturation, and blood volume during PDT without interruptions to the therapeutic illumination. Differences in saturation profiles between animals and treatment groups indicate differences in vascular response during illumination. Furthermore, the relationship between fluence rate and m‐THPC fluorescence photobleaching is complex in an interstitial environment. Lasers Surg. Med. 41:653–664, 2009. © 2009 Wiley‐Liss, Inc.
Simulations of measured photobleaching kinetics in human basal cell carcinomas suggest blood flow reductions during ALA‐PDT
Authors: Wang Ken Kang‐Hsin , Cottrell William J. , Mitra Soumya , Oseroff Allan R. , Foster Thomas H.
Published: October 2009

Background and Objective

In a recently completed pilot clinical study at Roswell Park Cancer Institute, patients with superficial basal cell carcinoma (sBCC) received topical application of 20% 5‐aminolevulinic acid (ALA) and were irradiated with 633 nm light at 10–150 mW cm−2. Protoporphyrin IX (PpIX) photobleaching in the lesion and the adjacent perilesion normal margin was monitored by fluorescence spectroscopy. In most cases, the rate of bleaching slowed as treatment progressed, leaving a fraction of the PpIX unbleached despite sustained irradiation. To account for this feature, we hypothesized a decrease in blood flow during ALA‐photodynamic therapy (PDT) that reduced the rate of oxygen transported to the tissue and therefore attenuated the photobleaching process. We have performed a detailed analysis of this hypothesis.

Study Design/Materials and Methods

We used a comprehensive, previously published mathematical model to simulate the effects of therapy‐induced blood flow reduction on the measured PpIX photobleaching. This mathematical model of PDT in vivo incorporates a singlet‐oxygen‐mediated photobleaching mechanism, dynamic unloading of oxygen from hemoglobin, and provides for blood flow velocity changes. It permits simulation of the in vivo photobleaching of PpIX in this patient population over the full range of irradiances and fluences.

Results

The results suggest that the physiological equivalent of discrete blood flow reductions is necessary to simulate successfully the features of the bleaching data over the entire treatment fluence regime. Furthermore, the magnitude of the blood flow changes in the normal tissue margin and lesion for a wide range of irradiances is consistent with a nitric‐oxide‐mediated mechanism of vasoconstriction.

Conclusion

A detailed numerical study using a comprehensive PDT dosimetry model is consistent with the hypothesis that the observed trends in the in vivo PpIX photobleaching data from patients may be explained on the basis of therapy‐induced blood flow reductions at specific fluences. Lasers Surg. Med. 41:686–696, 2009. © 2009 Wiley‐Liss, Inc.
Novel wavelengths for laser nerve stimulation
Authors: McCaughey Ryan G. , Chlebicki Cara , Wong Brian J.F.
Published: October 2009

Background

Laser light is known to stimulate nerves. This study investigated alternative wavelengths for nerve stimulation.

Materials and Methods

The sciatic nerves of rats were irradiated with four different lasers—a Ho:YAG (2100 nm), a Yb:glass fiber laser (1495 nm) and diode lasers (1450 nm and 1540 nm).

Results

All lasers evoked a visible leg twitch response, and electromyography confirmed muscle activation. The Yb:glass laser at 1495 nm delivered through a single mode fiber was found to be the most effective stimulus. The stimulation threshold for a 2 millisecond pulse from the Yb:glass laser was determined to be 3.7±2.8 mJ/cm2.

Conclusions

The Yb:glass laser has the potential for use in neurostimulation, as an alternative to electrical stimulation. Lasers Surg. Med. 42:69–75, 2010. © 2009 Wiley‐Liss, Inc.
Electrochemical corrosion behavior of X80 pipeline steel in a near‐neutral pH solution
Authors: Xue H. B. , Cheng Y. F.
Published: October 2009

In this work, the electrochemical corrosion behavior of X80 pipeline steel was investigated in a near‐neutral pH solution using electrochemical impedance spectroscopy (EIC) and photo‐electrochemical (PEC) measurements as well as X‐ray photo‐electron spectroscopy (XPS) technique. The effects of hydrogen‐charging and stress were considered. The results show that the steel is in an active dissolution state, and a layer of corrosion product is formed and deposited on the electrode surface, which is subjected to further oxidation to form ferric oxide and hydroxide. Photo‐illumination enhances anodic dissolution of the steel when it is under anodic polarization due to destroying of the corrosion product film. When the steel is under cathodic polarization, the cathodic current density decreases upon laser illumination due to the photo‐oxidation of hydrogen atoms generated during cathodic reactions, which behaves as an anodic reaction to offset the cathodic current density. Hydrogen‐charging and stress decrease the corrosion resistance of the steel and enhance the dissolution rate of the steel.
Surface Relief Gratings in Azobenzene‐Containing Polymers with Linear and Star‐Branched Architectures: A Comparison
Authors: Gharagozloo‐Hubmann Kati , Kulikovska Olga , Börger Volker , Menzel Henning , Stumpe Joachim
Published: October 2009

The influence of molecular architecture on light‐induced SRG formation was investigated. Polymers with different degree of branching were synthesized by ATRP and functionalized with azobenzene chromophores. The polymers differ only in their architecture – linear, 4‐, 6‐, or 12‐arms stars. The photo‐induced dichroism as well as the efficiency of SRG formation was similar for all polymers of this series. New consideration for the origin of the driving force was used to explain this behavior. The comparable SRG inscription rate in differently branched polymers can be rationalized by assuming that azobenzene acts as an internal molecular motor and can cause a non‐turbulent motion on a scale smaller than that on which normal entanglement restriction forces act.

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Steric Coordination Control of Interchain Interactions in Conducting Metallopolymers
Authors: He Susan , Dennis Ashlyn E. , Smith Rhett C.
Published: October 2009

The solution processability of a conducting metallopolymer (CMP1) based on a 2,2′‐bipyridyl (bipy) derivatized poly(p‐phenylene vinylene) (PPV) backbone has been accomplished by the strategic placement of sterically demanding mesityl side chains. The enhanced solubility of CMP1 can be traced to the prevention of coordinative crosslinking between polymer chains. The sterically enforced 1:1 bipy/metal ratio was confirmed by job analysis of absorption spectroscopic titration data. In addition to enhanced processability, this strategy also leads to twice as many metal ions, and consequently twice the charge, on CMP1 versus traditional bipyridyl‐PPV metallopolymers that are typified by a 2:1 bipy/metal ratio with certain metals.

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Determination of metabolite profiles in tropical wines by 1H NMR spectroscopy and chemometrics
Authors: da Silva Neto Humberto G. , da Silva João B. P. , Pereira Giuliano E. , Hallwass Fernando
Published: October 2009

Traditionally, wines are produced in temperate climate zones, with one harvest per year. Tropical wines are a new concept of vitiviniculture that is being developed, principally in Brazil. The new Brazilian frontier is located in the northeast region (São Francisco River Valley) in Pernambuco State, close to the equator, between 8 and 9°S. Compared with other Brazilian and worldwide vineyards, the grapes of this region possess peculiar characteristics. The aim of this work is a preliminary study of commercial São Francisco River Valley wines, analyzing their metabolite profiles by 1H NMR and chemometric methods. Copyright © 2009 John Wiley & Sons, Ltd.
1H and 13C NMR assignments of all three isomeric o‐fluoronaphthaldehydes and three o‐fluorophenanthrene aldehydes
Authors: Busacca Carl A. , Campbell Scot , Gonnella Nina C. , Senanayake Chris H.
Published: October 2009

Three isomeric o‐fluoronaphthaldehydes, 9‐fluorophenanthrene, and three previously unreported o‐fluorophenanthrene aldehydes were analyzed in detail by multiple NMR techniques to provide unambiguous assignment of structures and resonances. The six aldehydes serve as the key starting materials for novel chiral ligands used in highly enantioselective rhodium‐catalyzed asymmetric hydrogenation reactions. Copyright © 2009 John Wiley & Sons, Ltd.
Reactivity of the disilyne RSiSiR (R = SiiPr[CH(SiMe3)2]2) toward bis(silylcyanide) forming a 1,4‐diaza‐2,3‐disilabenzene analog
Authors: Takeuchi Katsuhiko , Ichinohe Masaaki , Sekiguchi Akira , Guo Jing‐Dong , Nagase Shigeru
Published: October 2009

The reaction of 1,1,4,4‐tetrakis[bis(trimethylsilyl)methyl]‐1,4‐diisopropyl‐2‐tetrasilyne 1 with 1,3‐bis(cyanodimethylsilyl)propane 4 produced the 1:1 adduct, 1,4‐diaza‐2,3‐disilabenzene analog 5 as deep red crystals, which was characterized by spectroscopic data and X‐ray crystallography. Theoretical calculations on the reaction between the disilyne and silylcyanide show that the reaction proceeds via σ‐coordination of silylcyanide, in which two molecules of silylcyanide coordinate with the sp‐silicon atoms of disilyne, enabling CC bond formation. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and characterization of thermoresponsive polymers containing reduction‐sensitive disulfide linkage
Authors: Li Lihua , Jiang Xulin , Zhuo Renxi
Published: October 2009

A novel class of thermoresponsive and reduction‐sensitive polymer, p(PEG‐MEMA‐co‐Boc‐Cyst‐MMAm), containing disulfide linkages and removable hydrophobic tert‐butyloxycarbonyl side chains was synthesized. The cloud points (CP) of p(PEG‐MEMA‐co‐Boc‐Cyst‐MMAm) in water determined by UV/VIS spectrometer were between 20 °C and 57 °C, which shows that the CP can be tuned by adjusting the copolymer composition. Moreover, the thermosensitive polymers p(PEG‐MEMA‐co‐Boc‐Cyst‐MMAm) formed stable nanoparticles in neutral aqueous medium, but rapidly destabilized in an reductive environment mimicking the intracellular space making them suitable for cytoplasmic drug delivery. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5989–5997, 2009
Well‐defined amphiphilic graft copolymer consisting of hydrophilic poly(acrylic acid) backbone and hydrophobic poly(vinyl acetate) side chains
Authors: Li Yaogong , Zhang Yaqin , Yang Dong , Feng Chun , Zhai Sujuan , Hu Jianhua , Lu Guolin , Huang Xiaoyu
Published: October 2009

A series of well‐defined amphiphilic graft copolymers containing hydrophilic poly(acrylic acid) (PAA) backbone and hydrophobic poly(vinyl acetate) (PVAc) side chains were synthesized via sequential reversible addition‐fragmentation chain transfer (RAFT) polymerization followed by selective hydrolysis of poly(tert‐butyl acrylate) backbone. A new Br‐containing acrylate monomer, tert‐butyl 2‐((2‐bromopropanoyloxy)methyl) acrylate, was first prepared, which can be polymerized via RAFT in a controlled way to obtain a well‐defined homopolymer with narrow molecular weight distribution (Mw/Mn = 1.08). This homopolymer was transformed into xanthate‐functionalized macromolecular chain transfer agent by reacting with o‐ethyl xanthic acid potassium salt. Grafting‐from strategy was employed to synthesize PtBA‐g‐PVAc well‐defined graft copolymers with narrow molecular weight distributions (Mw/Mn < 1.40) via RAFT of vinyl acetate using macromolecular chain transfer agent. The final PAA‐g‐PVAc amphiphilic graft copolymers were obtained by selective acidic hydrolysis of PtBA backbone in acidic environment without affecting the side chains. The critical micelle concentrations in aqueous media were determined by fluorescence probe technique. The micelle morphologies were found to be spheres. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6032–6043, 2009
Synthesis and eutectic behavior of liquid crystalline copolyesters
Authors: Wang Xiuzhen , Bu Haishan , Luise Robert R.
Published: October 2009

A series of liquid crystalline copolyesters, derived from 1,4‐hydroxy‐benzoic acid (HBA), 6‐hydroxy‐2‐naphthoic acid (HNA), terephthalic acid (TA), and hydroquinone (HQ), were prepared; crystallization, melting and solid‐state structure of the copolyesters were studied by using differential scanning calorimetry (DSC) and wide‐angle x‐ray diffraction (WAXD). It was found that the variation of melting point of the copolyesters with increasing HBA mol % exhibits eutectic melting behavior at a constant mole ratio of HNA, and the extrapolated eutectic temperature decreases linearly with increasing HNA mol %. WAXD analysis of the copolyesters indicates that the d‐spacing related to three‐dimensional order increases first and then decreases with increasing HBA mol %. The increase of the d‐spacing, consistent with looser packing of chains, leads to the reduction of melting point and most likely accounts for the eutectic behavior observed. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2171–2177, 2009
Enhanced hydrogen bonding and its dramatic impact on deformation behaviors in a biomedical poly(carbonate urethane) with fluorinated chain extender
Authors: Na Bing , Lv Ruihua , Xu Wenfei , Tian Nana , Li Jiehua , Tan Hong , Fu Qiang
Published: October 2009

The enhanced hydrogen bonding, manifested by significant frequency decreasing of both NH and CO stretching vibrations, is confirmed in a biomedical poly(carbonate urethane) with fluorinated chain extender. It gives rise to preferential association among hard segments and thus promoted microphase separation, which is responsible for the plastic deformation behaviors of the fluorinated poly(carbonate urethane). Furthermore, the segmental orientation, including both soft and hard segments, has been well correlated with the enhanced hydrogen bonding as well as promoted microphase separation. Under stretching large domains are prone to orient with their long axis along tensile direction and thus a negative orientation of hard segments is observed. Meanwhile, decreased orientation of soft segments can also find its origin in the reduced crosslinking density provided by hard domains because of preferential association among hard segments in such a biomedical material. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2198–2205, 2009
Poly(vinylpyrrolidone)‐based films grown on copper surfaces
Authors: De Amorim Alexandra Mara , Franzoi Ana Cristina , Oliveira Paula Nunes , Pires Alfredo Tibúrcio Nunes , Spinelli Almir , Bertolino José Roberto
Published: October 2009

The influence of molecular weight and the amount of the poly(vinylpyrrolidone) (PVP) on the growth of poly(vinylpyrrolidone)–based films on copper surfaces was studied by electrochemical, infrared and electronic spectroscopy, and thermogravimetric methods. Complex polymer/metal ions were deposited onto a copper surface, as the result of the electrochemically generated reaction of copper cations with PVP and SCN−, in sulfuric acid media. Spontaneous film growth on copper surfaces was generated and characterized as a Cu(II)/PVP/SCN− complex. Infrared spectra and thermal gravimetric curves of the films generated at + 0.7 V were compared with the chemically synthesized complex, and show the same patterns. The oxidation process can be described as: Cu(0)→Cu(I) and Cu(I)→Cu(II), and the copper complex formed at more positive potentials was characterized as Cu(II)/PVP/SCN−, with copper bonded to the oxygen atom of PVP and thiocyanate ligand N‐linked. This study focuses on the complex formation on a copper surface in acid media and its characterization through electrochemical and spontaneously generated reactions. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2206–2214, 2009
Determination of pyridoxal‐5′‐phosphate (PLP)‐bonding sites in proteins: a peptide mass fingerprinting approach based on diagnostic tandem mass spectral features of PLP‐modified peptides
Authors: Simon Eric S. , Allison John
Published: October 2009

Peptides modified by pyridoxal‐5′‐phosphate (PLP), linked to a lysine residue via reductive amination, exhibit distinct spectral characteristics in the collision‐induced dissociation (CID) tandem mass (MS/MS) spectra that are described here. The MS/MS spectra typically display two dominant peaks whose m/z values correspond to neutral losses of [H3PO4] (−98 Da) and the PLP moiety as [C8H10NO5P] (−231 Da) from the precursor peptide ion, respectively. Few other peaks are observed. Recognition of this distinct fragmentation behavior is imperative since determining sequences and sites of modifications relies on the formation of amide backbone cleavage products for subsequent interpretation via proteome database searching. Additionally, PLP‐modified peptides exhibit suppressed precursor ionization efficiency which diminishes their detection in complex mixtures. Presented here is a protocol which describes an enrichment strategy for PLP‐modified peptides combined with neutral loss screening and peptide mass fingerprinting to map the PLP‐bonding site in a known PLP‐dependent protein. This approach represents an efficient alternative to site‐directed mutagenesis which has been the traditional method used for PLP‐bonding site localization in proteins. Copyright © 2009 John Wiley & Sons, Ltd.
Anti‐inflammatory Properties of Cerium Oxide Nanoparticles
Authors: Hirst Suzanne M. , Karakoti Ajay S. , Tyler Ron D. , Sriranganathan Nammalwar , Seal Sudipta , Reilly Christopher M.
Published: October 2009

The valence and oxygen defect properties of cerium oxide nanoparticles (nanoceria) suggest that they may act as auto‐regenerative free radical scavengers. Overproduction of the free radical nitric oxide (NO) by the enzyme inducible nitric oxide synthase (iNOS) has been implicated as a critical mediator of inflammation. NO is correlated with disease activity and contributes to tissue destruction. The ability of nanoceria to scavenge free radicals, or reactive oxygen species (ROS), and inhibit inflammatory mediator production in J774A.1 murine macrophages is investigated. Cells internalize nanoceria, the treatment is nontoxic, and oxidative stress and pro‐inflammatory iNOS protein expression are abated with stimulation. In vivo studies show nanoceria deposition in mouse tissues with no pathogenicity. Taken together, it is suggested that cerium oxide nanoparticles are well tolerated in mice and are incorporated into cellular tissues. Furthermore, nanoceria may have the potential to reduce ROS production in states of inflammation and therefore serve as a novel therapy for chronic inflammation.
Nicotine withdrawal produces a decrease in extracellular levels of dopamine in the nucleus accumbens that is lower in adolescent versus adult male rats
Authors: Natividad Luis A. , Tejeda Hugo A. , Torres Oscar V. , O'dell Laura E.
Published: October 2009

The behavioral effects of nicotine withdrawal are lower in adolescent versus adult rats. However, the neurochemical mechanisms that mediate these developmental differences are unknown. Previous studies have shown that extracellular levels of dopamine in the nucleus accumbens (NAcc) are reduced in adult rats experiencing withdrawal. This study compared dopamine levels in the NAcc of male adolescent and adult rats experiencing nicotine withdrawal. Animals were prepared with subcutaneous pumps that delivered an equivalent nicotine dose in these age groups. Following 13 days of nicotine exposure, rats were implanted unilaterally with microdialysis probes into the NAcc and ipsilateral ventral tegmental area (VTA). The next day, dialysate levels were collected following systemic administration of the nicotinic‐receptor antagonist mecamylamine to precipitate withdrawal. Mecamylamine produced an average % decrease in NAcc dopamine that was lower in adolescents (20%) versus adults (44%). Similar developmental differences were observed with the dopaminergic (DOPAC and HVA) but not serotonergic (5‐HIAA) metabolites. A follow‐up study compared NAcc dopamine in adolescent and adult rats receiving intra‐VTA administration of bicuculline, which reduces γ‐aminobutyric acid (GABA) inhibition of dopamine transmission. The results revealed that blockade of GABAA receptors in the VTA produced a two‐fold increase in NAcc dopamine of adults but not adolescents. These results provide a potential mechanism involving dopamine that mediates developmental differences in nicotine withdrawal. Specifically, they suggest that GABA systems are underdeveloped during adolescence and this reduced inhibition of dopamine neurons in the VTA may lead to reduced decreases in NAcc dopamine of young animals experiencing withdrawal. Synapse 64:136–145, 2010. © 2009 Wiley‐Liss, Inc.
Building the developmental oculome: systems biology in vertebrate eye development and disease
Authors: Lachke Salil A. , Maas Richard L.
Published: October 2009

The vertebrate eye is a sophisticated multicomponent organ that has been actively studied for over a century, resulting in the identification of the major embryonic and molecular events involved in its complex developmental program. Data gathered so far provides sufficient information to construct a rudimentary network of the various signaling molecules, transcription factors, and their targets for several key stages of this process. With the advent of genomic technologies, there has been a rapid expansion in our ability to collect and process biological information, and the use of systems‐level approaches to study specific aspects of vertebrate eye development has already commenced. This is beginning to result in the definition of the dynamic developmental networks that operate in ocular tissues, and the interactions of such networks between coordinately developing ocular tissues. Such an integrative understanding of the eye by a comprehensive systems‐level analysis can be termed the ‘oculome’, and that of serial developmental stages of the eye as it transits from its initiation to a fully formed functional organ represents the ‘developmental oculome’. Construction of the developmental oculome will allow novel mechanistic insights that are essential for organ regeneration‐based therapeutic applications, and the generation of computational models for eye disease states to predict the effects of drugs. This review discusses our present understanding of two of the individual components of the developing vertebrate eye—the lens and retina—at both the molecular and systems levels, and outlines the directions and tools required for construction of the developmental oculome. Copyright © 2009 John Wiley & Sons, Inc.

This article is categorized under:

Developmental Biology > Developmental Processes in Health and Disease
Modeling childbirth: elucidating the mechanisms of labor
Authors: Li Xinshan , Kruger Jennifer A. , Nash Martyn P. , Nielsen Poul M.F.
Published: October 2009

The process of childbirth and the mechanisms of labor have been studied for over a century, beginning with simple measurements of fetal skull and maternal pelvis dimensions. More recently, X‐rays, ultrasound, and magnetic resonance imaging have been used to try and quantify the biomechanics of labor. With the development of computational technologies, biomechanical models have emerged as a quantitative analysis tool for modeling childbirth. These methods are well known for their capabilities to analyze function at the organ scale. This review provides an overview of the state‐of‐the‐art finite element models of the mechanics of vaginal delivery, with detailed descriptions of the data sources, modeling frameworks, and results. We also discuss the limitations and improvements required in order for the models to be more accurate and clinically useful. Some of the major challenges include: modeling the complex geometry of the maternal pelvic floor muscles and fetal head motion during the second stage of labor; the lack of experimental data on the pelvic floor structures; and development of methods for clinical validation. To date, models have had limited success in helping clinicians understand possible factors leading to birth‐induced pelvic floor muscle injuries and dysfunction. However, much more can be achieved with further development of these quantitative modeling frameworks, such as tools for birth planning and medical education. Copyright © 2009 John Wiley & Sons, Inc.

This article is categorized under:

Models of Systems Properties and Processes > Mechanistic Models
Women's Decision Making about Risk‐Reducing Strategies in the Context of Hereditary Breast and Ovarian Cancer: A Systematic Review
Authors: Howard A. Fuchsia , Balneaves Lynda G. , Bottorff Joan L.
Published: October 2009

Women who have a mutation in theBRCA1orBRCA2genes have up to an 87% lifetime risk of breast cancer and up to a 40% lifetime risk of ovarian cancer. Cancer prevention and early detection strategies are often considered by these women to address this heightened risk. Risk‐reducing strategies include risk‐reducing mastectomy and oophorectomy, breast and ovarian cancer screening, and chemoprevention. This systematic literature review summarizes the factors and contexts that influence decision making related to cancer risk‐reducing strategies among women at high‐risk for hereditary breast and ovarian cancer. In the 43 published research articles reviewed, three main types of factors are identified that influence high‐risk women's decisions about risk‐reducing strategies: a) medical and physical factors, b) psychological factors and c) social context factors. How these factors operate in women's lives over time remains unknown, and would best be elucidated through prospective, longitudinal research, as well as qualitative research.
Neurotechnologist Reference Guide
Authors: Satterthwait Roshelle
Published: October 2009

Neurotechnologist Reference Guide Trent Long, Daniel Slepian, Richard Slepian and Mark B. Twede 2nd edition 2009, ORIMtec 138 pages, $49.95 spiralbound
Scavenger receptor control of chromogranin A‐induced microglial stress and neurotoxic cascades
Authors: Hooper Claudie , Fry Victoria A.H. , Sevastou Ioanna G. , Pocock Jennifer M.
Published: October 2009

Chromogranin A (CgA), a neuroactive glycoprotein, is associated with microglial activation cascades implicated in neurodegeneration. Here we show that CgA‐dependent inducible nitric oxide synthase (iNOS) expression and stress responses in microglia involved signalling via scavenger receptors (SR), since SR class‐A (SR‐A) ligands blocked iNOS expression, mitochondrial depolarisation, apoptosis and glutamate release. Furthermore, block of SR‐A ameliorated CgA‐induced microglial neurotoxicity. In contrast, block of CD36, or the receptor for advanced glycation end products (RAGE) did not prevent CgA‐induced microglial activation and neurotoxicity. Thus, manipulation of specific scavenger receptor‐coupled signalling pathways may provide avenues for therapeutic intervention in neurodegenerative diseases implicating microglial activation with chromogranin peptides.
Lake Levels and Sedimentary Environments During Deposition of the Trego Hot Springs and Wono Tephras in the Lake Lahontan Basin, Nevada, USA
Authors: Adams Kenneth D.
Published: October 2009

The Wono and Trego Hot Springs (THS) tephras are widespread in the Lahontan basin and have been identified in a variety of sedimentary environments at different elevations. Davis (1983) reported lake level to be at about 1256 m when the THS tephra was deposited, an interpretation questioned by Benson et al. (1997) who interpreted lake level to be ≤1177 m at that time. This is a significant difference in lake size with important implications for interpreting the climate that prevailed at that time. Based on new interpretations of depositional settings of the THS bed at multiple sites, the larger lake size is correct. Additional sites containing the Wono tephra indicate that it was deposited when lake level was at about 1217 m in the western subbasins and at about 1205 m in the Carson Sink. Sedimentary features associated with progressively deeper paleowater depths follow a predictable pattern that is modulated by proximity to sediment sources and local slope. Fine to coarse sands with wave-formed features are commonly associated with relatively shallow water. Silty clay or clay dominates in paleowater depths >25 m, with thin laminae of sand and ostracods at sites located adjacent to or downslope from steep mountain fronts.
The ligamental formations ofMargaritifera margaritifera(L.) (Bivalvia: Margaritiferidae) andMytilus edulis(L.) (Bivalvia: Mytilidae) during larval and postlarval ontogenesis
Authors: Pennec Marcel Le , Jüngbluth Jürgen H.
Published: October 2009

The analysis under a scanning electron microscope of young larval and postlarval shells ofMytilus edulisandMargaritifera margaritiferareveals some primitive characters. Among these features, the most important are the ligamental formations which are described in detail during ontogenesis. InM. edulisa primitive ligament appears in a pit under the cardinal plateau immediately following metamorphosis. A second ligament later develops on the posterior edge of the shell, and becomes the only ligament present in the adult. InM. margaritiferaa provisional internal structure acts as a ligament in the young glochidia fish parasites. A definitive external ligament only develops following metamorphosis of the glochidia.

The similar pattern of development of these ligaments in both species may represent the development of the ligament in the first bivalves.
The sterol composition of some shark livers
Authors: Morris R. J. , Ballantine J. A. , Roberts J. C.
Published: October 2009

The results of detailed sterol analyses on the livers of seven species of sharks are presented. The sharks appear to have a very specific requirement for cholesterol as their sole component sterol (> 99 % total sterols), which several species of bony fish do not. In fact, from their sterol composition, sharks appear more similar to terrestrial vertebrate classes than bony fish. If, as has been suggested, sterol composition is a measure of evolutionary advancement, then this work presents biochemical evidence that sharks are not as primitive as has sometimes been assumed.