bluuebunny/crossref_metadata_2025 huggingface dataset:
Epidermal growth factor receptor regulates osteoclast differentiation and survival through cross‐talking with RANK signaling
Authors: Yi TacGhee , Lee Hye‐Lim , Cha Ji‐Hoon , Ko Soo‐Il , Kim Hye‐Jin , Shin Hong‐In , Woo Kyung‐Mi , Ryoo Hyun‐Mo , Kim Gwan‐Shik , Baek Jeong‐Hwa
Published: June 2008

The epidermal growth factor receptor (EGFR) functions in various cellular physiological processes such as proliferation, differentiation, and motility. Although recent studies have reported that EGFR signaling is involved in osteoclast recruitment and formation, the molecular mechanism of EGFR signaling for the regulation of osteoclastogenesis remains unclear. We investigated the role of the EGFR in osteoclast differentiation and survival and show that the expression of the EGFR was highly up‐regulated by receptor activator of nuclear factor‐κB ligand (RANKL) during osteoclast differentiation. EGFR‐specific tyrosine kinase inhibitors and EGFR knockdown blocked RANKL‐dependent osteoclast formation, suggesting that EGFR signaling plays an important role in osteoclastogenesis. EGFR inhibition impaired the RANKL‐mediated activation of osteoclastogenic signaling pathways, including c‐Jun N‐terminal kinase (JNK), NF‐κB, and Akt/protein kinase B (PKB). In addition, EGFR inhibition in differentiated osteoclasts caused apoptosis through caspase activation. Inhibition of the phosphoinositide‐3 kinase (PI3K)‐Akt/PKB pathway and subsequent activation of BAD and caspases‐9 and ‐3 may be responsible for the EGFR inhibition‐induced apoptosis. The EGFR physically associated with receptor activator of nuclear factor‐κB (RANK) and Grb2‐associated binder 2 (Gab2). Moreover, RANKL transactivated EGFR. These data indicate that EGFR regulates RANKL‐activated signaling pathways by cross‐talking with RANK, suggesting that the EGFR may play a crucial role as a RANK downstream signal and/or a novel type of RANK co‐receptor in osteoclast differentiation and survival. J. Cell. Physiol. 217: 409–422, 2008. © 2008 Wiley‐Liss, Inc.
Updating the effects of fatty acids on skeletal muscle
Authors: Silveira Leonardo R. , Fiamoncini Jarlei , Hirabara Sandro M. , Procópio Joaquim , Cambiaghi Tavane D. , Pinheiro Carlos Hermano J. , Lopes Lúcia R. , Curi Rui
Published: June 2008

In this review we updated the fatty acid (FA) effects on skeletal muscle metabolism. Abnormal FA availability induces insulin resistance and accounts for several of its symptoms and complications. Efforts to understand the pathogenesis of insulin resistance are focused on disordered lipid metabolism and consequently its effect on insulin signaling pathway. We reviewed herein the FA effects on metabolism, signaling, regulation of gene expression and oxidative stress in insulin resistance. The elevated IMTG content has been associated with increased intracellular content of diacylglycerol (DAG), ceramides and long‐chain acyl‐coenzyme A (LCA‐CoA). This condition has been shown to promote insulin resistance by interfering with phosphorylation of proteins of the insulin pathway including insulin receptor substrate‐1/2 (IRS), phosphatidylinositol‐3‐kinase, (PI3‐kinase) and protein kinase C. Although the molecular mechanism is not completely understood, elevated reactive oxygen (ROS) and nitrogen species (RNS) are involved in this process. Elevated ROS/RNS activates nuclear factor‐kappaB (NFkB), which promotes the transcription of proinflammatory tumoral necrosis factor alpha (TNFα), decreasing the insulin response. Therefore, oxidative stress induced by elevated FA availability may constitute one of the major causes of insulin resistance in skeletal muscle. J. Cell. Physiol. 217: 1–12, 2008. © 2008 Wiley‐Liss, Inc.
Overexpression of spindlin1 induces metaphase arrest and chromosomal instability
Authors: Zhang Peng , Cong Bin , Yuan Hongfeng , Chen Lin , Lv Yang , Bai Cixian , Nan Xue , Shi Shuangshuang , Yue Wen , Pei Xuetao
Published: June 2008

Spin/Ssty gene family is high conserved and very abundant transcript involved in gametogenesis, which was repeatedly detected in early embryo. Nevertheless, the biologic roles of the members are still largely unknown. Previously we have identified human gene spindlin1 as a homologue of the family from ovarian cancer cells, and reported that stable overexpression of spindlin1 could transform NIH3T3 cells and induce tumorigenesis in nude mouse. Here, we showed that spindlin1, as a nuclear protein, was relocated during mitosis. A fraction of spindlin1 proteins was dynamic distributed along mitotic spindle tubulin and enriched at midzone following anaphase entering. We also showed that transient overexpression of spindlin1 induced cell cycle delay in metaphase, caused mitotic spindle defects, and resulted in chromosome instability, micronucleus and multinuclear giant cells formation. Moreover, time‐lapse microscopy revealed that these cells arrested at metaphase for more than 3 h with chromosome nondisjunction or missegregation. Furthermore, Mad2 up‐regulation in these cells suggested that overexpression of spindlin1 may affect the bipolar spindle correctly attachment to chromosomes and activate spindle checkpoint. Taken together, these data demonstrated that excess spindlin1 protein may be detrimental for spindle microtubule organization, chromosomal stability and can potentially contribute to the development of cancer. J. Cell. Physiol. 217: 400–408, 2008. © 2008 Wiley‐Liss, Inc.
IL‐6/sIL‐6R enhances cathepsin B and L production via caveolin‐1‐mediated JNK‐AP‐1 pathway in human gingival fibroblasts
Authors: Yamaguchi Tomoko , Naruishi Koji , Arai Hideo , Nishimura Fusanori , Takashiba Shogo
Published: June 2008

Interleukin (IL)‐6 has an important role in inflammatory diseases. Lysosomal enzymes cathepsins are widely expressed as cysteine proteases regulating inflammatory process. Caveolin‐1 (Cav‐1) is a scaffolding/regulatory membrane protein that interacts with signaling molecules. In this study, we investigated the role of Cav‐1 on (1) the productivity, and (2) the enzymatic activity of cathepsin B and L in human gingival fibroblasts (HGFs) treated with IL‐6 in the presence of soluble form of IL‐6 receptor (sIL‐6R). At first, we established the siRNA‐mediated Cav‐1 down‐regulating in vitro systems by transient transfection of Cav‐1 siRNA. The siRNA‐mediated Cav‐1 down‐regulated cells were treated with IL‐6/sIL‐6R for indicated times. Then, cell lysates were collected, and examined the IL‐6‐induced signaling pathway, cathepsin B and L production, and measurement of cathepsins activity. To investigate the cathepsin L activity, cathepsin‐(B + L) activity was measured after pretreatment with CA‐074Me, a specific inhibitor for cathepsin B. We found that IL‐6/sIL‐6R enhanced significantly both production and activity of cathepsin B and L in HGFs. Interestingly, IL‐6‐mediated phosphorylation of both p44/42 MAPK and JNK was dramatically suppressed in Cav‐1 down‐regulated HGFs treated with IL‐6/sIL‐6R. In addition, both production and activity of cathepsin B and L were also significantly suppressed. Importantly, we demonstrated that JNK inhibition, but not p44/42 MAPK inhibition, significantly diminished IL‐6/sIL‐6R‐induced cathepsin B and L production. Taken together, we concluded that IL‐6/sIL‐6R enhances cathepsin B and L production via IL‐6/sIL‐6R‐mediated Cav‐1‐JNK‐AP‐1 pathway in HGFs. Our findings indicate that Cav‐1 might be a therapeutic target for IL‐6‐mediated tissue degradation in periodontitis. J. Cell. Physiol. 217: 423–432, 2008. © 2008 Wiley‐Liss, Inc.
Designed electromagnetic pulsed therapy: Clinical applications
Authors: Gordon Glen A.
Published: June 2008

The article to which this erratum refers was published in J Cell Phys (2007) 212: 579–582. © 2008 Wiley‐Liss, Inc.
Continuous production of 1,2‐propanediol by the selective hydrogenolysis of solvent‐free glycerol under mild conditions
Authors: Huang Long , Zhu Yu‐Lei , Zheng Hong‐Yan , Li Yong‐Wang , Zeng Zhi‐Yong
Published: June 2008

BACKGROUND: The conversion of glycerol to value‐added derivatives is now critical, owing to the large surplus of glycerol from biodiesel production. The main objective of this work is to develop a novel process for converting solvent‐free glycerol to 1,2‐propanediol.

RESULTS: Several catalysts were screened for aqueous‐phase hydrogenolysis of glycerol in an autoclave. The most effective catalysts (Ni/Al2O3, Cu/ZnO/Al2O3) were further tested for vapor phase hydrogenolysis in a fixed‐bed. Ni/Al2O3 did not prove as effective for the production of 1,2‐propanediol because of the high selectivity to CH4 and CO. Over Cu/ZnO/Al2O3, glycerol was mainly converted to the desired 1,2‐propanediol and the reaction intermediate acetol. The production of 1,2‐propanediol was favoured at higher hydrogen pressure. At 190 °C and 0.64 MPa, near complete conversion of glycerol was achieved with 1,2‐propanediol selectivity up to 92%. In addition, a higher concentration (between 43.4% and 0.8%) of acetol was detected and an approximately stoichiometric relationship was found between acetol and 1,2‐propanediol.

CONCLUSION: 1,2‐propanediol can be produced with high yields via the vapor phase hydrogenolysis of glycerol over Cu/ZnO/Al2O3. Furthermore, the mechanism of 1,2‐propanediol formation is suggested to proceed mainly through an acetol route over Cu/ZnO/Al2O3. Copyright © 2008 Society of Chemical Industry
Exogenous tumor necrosis factor‐α rapidly alters synaptic and sensory transmission in the adult rat spinal cord dorsal horn
Authors: Youn Dong‐ho , Wang Haibin , Jeong Sung‐Jin
Published: June 2008

The proinflammatory cytokine tumor necrosis factor‐α (TNF‐α) is involved in the generation of inflammatory and neuropathic pain. This study investigated if TNF‐α has any effect on spinal synaptic and/or sensory transmission by using whole‐cell recordings of substantia gelatinosa (SG) neurons in transverse lumbar spinal cord slices of adult rats and by using behavioral tests. After intrathecal administration of TNF‐α in adult rats, spontaneous hind paw withdrawal behavior and thermal hyperalgesia were rapidly induced (∼30 min), while mechanical allodynia slowly developed. Bath application of TNF‐α (0.1–1 nM, 8 min) depressed peak amplitude of monosynaptic Aδ and C fiber–evoked excitatory postsynaptic currents (EPSCs) without changing in holding currents and input resistances, whereas this application generally potentiated polysynaptic Aδ fiber‐evoked EPSCs. Moreover, the frequencies, but not the amplitudes, of spontaneous and miniature EPSCs and spontaneous inhibitory postsynaptic currents were significantly increased by bath‐applied TNF‐α in most of the SG neurons. The effects of TNF‐α on Aδ/C fiber–evoked monosynaptic and polysynaptic or spontaneous EPSCs were significantly blocked by 5 μM TNF‐α antagonist that inhibits TNF‐α binding to its type 1 receptor (TNFR1). Because this study also found high protein expression of TNFR1 in the adult dorsal root ganglion and no change of α‐amino‐3‐hydroxy‐5‐methylisoxazole‐4‐propionic acid (AMPA) induced whole‐cell currents by TNF‐α, we conclude that presynaptic TNFR1 at Aδ/C primary afferent terminals contributes to the rapid alteration of synaptic transmission in the spinal SG, and the development of abnormal pain hypersensitivity by exogenous TNF‐α. © 2008 Wiley‐Liss, Inc.
Differential neuroprotective effects of carnosine, anserine, and N‐acetyl carnosine against permanent focal ischemia
Authors: Min Jiangyong , Senut Marie‐Claude , Rajanikant Krishnamurthy , Greenberg Eric , Bandagi Ram , Zemke Daniel , Mousa Ahmad , Kassab Mounzer , Farooq Muhammad U. , Gupta Rishi , Majid Arshad
Published: June 2008

Carnosine (β‐alanyl‐L‐histidine) has been shown to exhibit neuroprotection in rodent models of cerebral ischemia. In the present study, we further characterized the effects of carnosine treatment in a mouse model of permanent focal cerebral ischemia and compared them with its related peptides anserine and N‐acetylated carnosine. We also evaluated the efficacy of bestatin, a carnosinase inhibitor, in ameliorating ischemic brain damage. Permanent focal cerebral ischemia was induced by occlusion of the middle cerebral artery (pMCAO). Mice were subsequently randomly assigned to receive an intraperitoneal injection of vehicle (0.9% saline), carnosine, N‐acetyl carnosine, anserine, bestatin alone, or bestatin with carnosine. Infarct size was examined using 2,3,5‐triphenyltetrazolium chloride staining 1, 3, and 7 days following pMCAO, and neurological function was evaluated using an 18‐point‐based scale. Brain levels of carnosine were measured in treated mice using high‐performance liquid chromatography 1 day following pMCAO. We demonstrated that treatment with carnosine, but not its analogues, was able to significantly reduce infarct volume and improve neurological function compared with those in vehicle‐treated mice. These beneficial effects were maintained for 7 days post‐pMCAO. In contrast, compared with the vehicle‐treated group, bestatin‐treated mice displayed an increase in the severity of ischemic lesion, which was prevented by the addition of carnosine. These new data further characterize the neuroprotective effects of carnosine and suggest that carnosine may be an attractive candidate for testing as a stroke therapy. © 2008 Wiley‐Liss, Inc.
Therapeutic benefits of intrathecal protein therapy in a mouse model of amyotrophic lateral sclerosis
Authors: Ohta Yasuyuki , Kamiya Tatsushi , Nagai Makiko , Nagata Tetsuya , Morimoto Nobutoshi , Miyazaki Kazunori , Murakami Tetsuro , Kurata Tomoko , Takehisa Yasushi , Ikeda Yoshio , Asoh Sadamitsu , Ohta Shigeo , Abe Koji
Published: June 2008

When fused with the protein transduction domain (PTD) derived from the human immunodeficiency virus TAT protein, proteins can cross the blood–brain barrier and cell membrane and transfer into several tissues, including the brain, making protein therapy feasible for various neurological disorders. We have constructed a powerful antiapoptotic modified Bcl‐XLprotein (originally constructed from Bcl‐XL) fused with PTD derived from TAT (TAT‐modified Bcl‐XL), and, to examine its clinical effectiveness in a mouse model of familial amyotrophic lateral sclerosis (ALS), transgenic mice expressing human Cu/Zn superoxide dismutase (SOD1) bearing a G93A mutation were treated by intrathecal infusion of TAT‐modified Bcl‐XL. We demonstrate that intrathecally infused TAT‐fused protein was effectively transferred into spinal cord neurons, including motor neurons, and that intrathecal infusion of TAT‐modified Bcl‐XLdelayed disease onset, prolonged survival, and improved motor performance. Histological studies show an attenuation of motor neuron loss and a decrease in the number of cleaved caspase 9‐, cleaved caspase 3‐, and terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labeling (TUNEL)‐positive cells in the lumbar cords of TAT‐modified Bcl‐XL‐treated G93A mice. Our results indicate that intrathecal protein therapy using a TAT‐fused protein is an effective clinical tool for the treatment of ALS. © 2008 Wiley‐Liss, Inc.
Abnormal growth of the corticospinal axons into the lumbar spinal cord of the hyt/hyt mouse with congenital hypothyroidism
Authors: Hsu Jung‐Yu C. , Stein Stuart A. , Xu Xiao‐Ming
Published: June 2008

Thyroid hormone deficiency may cause severe neurological disorders resulting from developmental deficits of the central nervous system. The mutant hyt/hyt mouse, characterized by fetal‐onset, life‐long hypothyroidism resulting from a point mutation of the thyroid‐stimulating hormone receptor of the thyroid gland, displays a variety of abnormalities in motor behavior that are likely associated with dysfunctions of specific brain regions and a defective corticospinal tract (CST). To test the hypothesis that fetal and neonatal hypothyroidism cause abnormal CST development, the growth of the CST was investigated in hypothyroid hyt/hyt mice and their euthyroid progenitors, the BALB/cByJ mice. Anterograde labeling with biotinylated dextran amine demonstrated a decrease in the number of CST axons in the hyt/hyt mouse at the first lumbar level at postnatal day (P) 10. After retrograde tracing with fast blue (FB), fewer FB‐labeled neurons were found in the motor cortex, the red nucleus, and the lateral vestibular nucleus of the hyt/hyt mouse. At the fourth lumbar level, the hyt/hyt mouse also showed smaller CST cross‐sectional areas and significantly lower numbers of unmyelinated axons, myelinated axons, and growth cones within the CST during postnatal development. At P10, the hyt/hyt mouse demonstrated significantly lower immunoreactivity of embryonic neural cell adhesion molecule in the CST at the seventh cervical level, whereas the expression of growth‐associated protein 43 remained unchanged. Our study demonstrated an abnormal development of the CST in the hyt/hyt mouse, manifested by reduced axon quantity and retarded growth pattern at the lumbar spinal cord. © 2008 Wiley‐Liss, Inc.
Transcriptional changes in insulin‐ and lipid metabolism‐related genes in the hippocampus of olfactory bulbectomized mice
Authors: Gass Peter , Leonardi‐Essmann Fernando , Zueger Maha , Spanagel Rainer , Gebicke‐Haerter Peter J.
Published: June 2008

Affymetrix chips were used to perform a hypothesis‐free large‐scale screening of transcripts in the hippocampus of olfactory bulbectomized mice, an established animal model of depression. Because only 11 transcripts were significantly changed, the statistically subsequent 25 transcripts below the significance level were additionally included in a first round of qRT‐PCR evaluations. Furthermore, all 36 genes were then tested for mutual interactions or interactions with other molecules in a physiological context using PathwayArchitect software. Thirty of them were displayed in a network interacting with at least one partner molecule from the list or with other partner molecules known from the literature. All partner molecules from the most prominent 10 molecules of this network were then identified and put together into a new list. On those grounds, the hypothesis was made that metabolic network components of the insulin signaling pathway are perturbed in the disease. This pathway was subsequently tested by a second round of qRT‐PCR, adding also a few additional candidate molecules belonging to this pathway. It turned out that the key target—FABP7—fell into the group of transcripts not significantly regulated within the chip data, and another key target—IRS1—did not show up in the chip experiments at all. In conclusion, our data reveal a problem with adhering to statistical significances in microarray experiments, insofar as molecules important for the disease may fall into the range of statistical noise. This approach may also be useful to find new targets for pharmacotherapy in affective disorders. © 2008 Wiley‐Liss, Inc.
Seasonal changes of CLA isomers and other fatty acids of milk fat from grazing dairy herds in the Azores
Authors: Rego Oldemiro A , Rosa Henrique JD , Regalo Susana M , Alves Susana P , Alfaia Cristina MM , Prates José AM , Vouzela Carlos M , Bessa Rui JB
Published: June 2008

BACKGROUND: Season of the year associated with dietary changes has been recognized as a factor implicated in milk fat fatty acid (FA) profile in dairy cows. However, a lack of information exists concerning cows grazing all year round as is practiced in the Azores, where cows are supplemented in winter with maize silage plus concentrates, while in spring the higher grass allowance only requires supplementation with concentrate. The main objective of this study was to detect any seasonal variation of FA profile of milk fat from milk sampled in bulk tanks of 12 Azorean dairy herds.

RESULTS Compared to winter milk, milk fat from spring presented a higher proportion of CLA cis‐9,trans‐11 (14.3 versus 9.6 g kg−1 FA), C18:1 trans‐11 (32 versus 22 g kg−1 FA), C18:2 trans‐11,cis‐15 (3.7 versus 2.2 g kg−1 FA), CLA trans‐11,cis‐13 (0.34 versus 0.23 g kg−1 FA) and C18:3 n‐3 (5.7 versus 5.4 g kg−1 FA). The C18:2 n‐6/C18:3 n‐3 ratio was lower (P < 0.05) in spring. Branched‐chain FA, except the anteiso‐C15:0, were higher in spring, while odd‐chain FA (C15:0) were higher in winter.

CONCLUSION: Dairy herd management in the Azores presents a seasonal variation of milk fat FA composition, where the spring milk may present increased potential benefits for human consumers. Copyright © 2008 Society of Chemical Industry
Poly(phenylacetylene)s Carrying Siloxy, Carbonate, and Hydroxy Groups: Synthesis and Properties
Authors: Saeed Irfan , Shida Yuichi , Khan Fareha Zafar , Shiotsuki Masashi , Masuda Toshio
Published: June 2008

t‐Butyldimethylsilyl (t‐BDMS) and t‐butoxycarbonyl (t‐Boc) protected 3‐ and 4‐hydroxyphenylacetylene monomers were synthesized and polymerized using [(nbd)RhCl]2 (1) and [(nbd)RhBPh4] (2) catalysts. The t‐BDMS‐containing polymers [poly(3a) and poly(4a)] were obtained in good yield (45–69%) while the t‐Boc‐protected monomers polymerized in a high yield [poly(5a) and poly(6a): 80–100%]. The use of KN(SiMe3)2 as a cocatalyst in conjunction with 1 led to a dramatic increase in the molecular weight of the polymers. The acid‐catalyzed removal of the t‐BDMS group afforded the naked hydroxy‐containing polymers [poly(3b) and poly(4b)] which cannot be obtained directly by the polymerization of the corresponding monomers. The polymers containing protected OH moieties were more soluble in less polar solvents, whereas their deprotected counterparts displayed good solubility in polar protic or highly polar aprotic solvents. The attempts to accomplish the free‐standing membrane fabrication by solution casting were successful only for poly(3a) and an augmentation in the gas permeability was discerned in comparison with the unsubstituted poly(phenylacetylene) and poly(o‐methylphenylacetylene).

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Two Coexisting Modes in Field‐Assisted AFM Nanopatterning of Thin Polymer Films
Authors: Xie Xian Ning , Chung Hong Jing , Bandyopadhyay Dipankar , Sharma Ashutosh , Sow Chorng Haur , Bettiol Andrew Anthony , Wee Andrew Thye Shen
Published: June 2008

Two coexisting mechanisms, i.e., electrohydrodynamic destabilization and electrostatic detachment, for polymer nanostructuring in field‐assisted atomic force microscope nanolithography are presented. The electrohydrodynamic destabilization mechanism is based on the surface instability of molten polymer film in the form of surface waves, and it leads to the formation of well defined polymeric wave patterns. The electrostatic detachment mechanism is associated with nano‐blister formation caused by pre‐existing defects, such as buried cavities in the polymer, and is responsible for the creation of hollow pillar‐like structures. Here, the coexistence and pattern formation probability of the two polymer patterning modes under similar nanolithographic conditions are discussed. It was found that the field strength and the efficiency of probe‐induced joule heating can significantly change the flow property of the polymer, which eventually leads to the occurrence of the two modes. The results presented here are useful in obtaining a complete picture of the diverse behaviors of polymers in AFM nanolithographic operations.

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Can the First Addition of Alkyl Radicals Play a Role in the Fate of NMP?
Authors: Bagryanskaya Elena , Bertin Denis , Gigmes Didier , Kirilyuk Igor , Marque Sylvain R. A. , Reznikov Vladimir , Roshchupkina Galina , Zhurko Irina , Zubenko Dmitry
Published: June 2008

Values of kd for the CON bond homolysis were measured for alkoxyamines based on imidazoline and imidazole nitroxides. They were analyzed in terms of polar/stabilization, steric, and entropic effects. kd decreased with increasing electron‐withdrawing capacities of the groups attached to the nitroxide, but increasing with both the bulkiness of the group attached to the nitroxide and the presence of substituents on the ring. With three alkoxyamines, it was shown that the fate of the NMP of styrene depended on the type of initiating alkyl radical: successful for initiating 1‐phenylethyl radicals and unsuccessful for initiating p‐nitrophenyloxycarbonyl‐2‐prop‐2‐yl radicals.

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Synthesis of High Density Polymer Brushes on Nanoparticles by Combined RAFT Polymerization and Click Chemistry
Authors: Ranjan Rajesh , Brittain William J.
Published: June 2008

In the present paper, we report the successful preparation of high density, well‐defined polymer brushes by RAFT polymerization on silica nanoparticles. Our strategy includes (i) “grafting from” approach for brush formation, (ii) facile click reaction to immobilize RAFT agent, (iii) synthesis of R‐supported chain transfer agent (CTA) over Z‐supported CTA, and (iv) use of more active trithiocarbonate RAFT agent over conventional dithioester type RAFT agent. With the advantage of the properties of high‐density polymer brushes, these diblock copolymer‐modified silica nanoparticles open the route to the elaboration of a new family of nanocomposite colloids with potential applications in responsive or smart systems.

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Aggregation Behavior of Homo‐PS/PS‐b‐P2VP Blends at the Air/Water Interface
Authors: Wen Gangyao , Chung Bonghoon , Chang Taihyun
Published: June 2008

The mixed Langmuir monolayers and Langmuir–Blodgett (LB) films of homo‐polystyrene (h‐PS) and the diblock copolymer polystyrene‐block‐poly(2‐vinylpyridine) (PS‐b‐P2VP) have been characterized by the Langmuir monolayer technique and tapping mode atomic force microscopy (AFM), respectively. When the content of h‐PS is below 80 wt.‐%, the mixed LB films of h‐PS/PS‐b‐P2VP mainly exhibit isolated circular nanoaggregates. With a further increase of the h‐PS content (80–95%), however, highly uniform and stable necklace‐network structures are observed in the mixed LB films.

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Metal Salt‐Induced Ferroelectric Crystalline Phase in Poly(vinylidene fluoride) Films
Authors: Yoon Sun , Prabu Arun Anand , Kim Kap Jin , Park Cheolmin
Published: June 2008

In this Communication, the effect of varying mass fractions (0–20 wt.‐%) of calcium chloride (CaCl2) salt on the α‐ and β‐phase content of poly(vinylidene fluoride) (PVDF) as‐cast films were investigated. Spectral and X‐ray studies revealed the maximum ferroelectric β‐phase for the addition of 15 wt.‐% of CaCl2 in PVDF compared to neat PVDF samples. The dense β‐phase dominant PVDF–CaCl2 (15 wt.‐%) thick film used as a ferroelectric insulator in one‐capacitor (1C) type random access memory device exhibited a remnant polarization of 3.1 µC · cm2, and is a good indication that the unoriented PVDF–CaCl2 films can be used in electronic applications without further stretching process.

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Click Chemistry: A Powerful Tool to Create Polymer‐Based Macromolecular Chimeras
Authors: Le Droumaguet Benjamin , Velonia Kelly
Published: June 2008

The combination of polymeric with biological materials, to create biohybrid macromolecules that merge the properties of both the natural and synthetic components, is a flourishing area in both life sciences and biotechnology. The click chemistry philosophy has recently provided a powerful tool in this direction, leading to a plethora of novel, tailor‐made biomacromolecules with unprecedented structural characteristics and properties. The different synthetic strategies, using the alkyne–azide click cycloadditions to bioorthogonally achieve the coupling of synthetic polymers with nucleic acids, peptides, sugars, proteins or even viruses and cells is described. The review covers the latest developments in this very dynamic and rapidly expanding field.

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A “Click” Strategy for Tuning in situ the Hydrophilic–Hydrophobic Balance of AB Macrosurfactants
Authors: Zarafshani Zoya , Akdemir Özgür , Lutz Jean‐François
Published: June 2008

The self‐organization of amphiphilic block copolymers in water strongly depends on their molecular structure, in particular on their hydrophilic–hydrophobic balance. Herein, a simple method for tuning the amphiphilicity of polymeric macrosurfactants in aqueous medium is proposed. This concept relies on the “click” ligation of an amphiphilic block copolymer (AB type) and a hydrophilic homopolymer (B type). In the present communication, the validity of this approach was examined with model polymers based on polystyrene (PS) and poly[oligo (ethylene glycol) acrylate] (POEGA) segments. A well‐defined ω‐azido functional diblock copolymer PS‐b‐POEGA and an α‐alkyne functional homopolymer POEGA were prepared using atom transfer radical polymerization. These two polymers could be efficiently coupled to each other via copper‐catalyzed azide–alkyne click chemistry in aqueous medium. Moreover, in this coupling strategy, an ester group was introduced at the junction between AB and B segments. This labile moiety may be “cut” by hydrolysis.

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Access to Three‐Arm Star Block Copolymers by a Consecutive Combination of the Copper(I)‐Catalyzed Azide–Alkyne Cycloaddition and the RAFT Hetero Diels–Alder Concept
Authors: Sinnwell Sebastian , Inglis Andrew J. , Stenzel Martina H. , Barner‐Kowollik Christopher
Published: June 2008

Three‐arm star block copolymers have been synthesized from linear polystyrene (PS) and poly(ε‐caprolactone) (PCL) building blocks. Through the use of an α‐diene‐ω‐alkyne functionalized PCL, the PS‐b‐PCL stars have been synthesized via either forming the PS‐b‐PCL arms first with the hetero Diels–Alder (HDA) cycloaddition and their subsequent coupling to a triazide coupling agent through a copper(I)‐catalyzed azide–alkyne cycloaddition (CuAAC) (arm‐first) or via forming the basic star structure first through the CuAAC of the coupling agent and the PCL, with the diblock stars achieved by the subsequent HDA cycloaddition with the PS (core‐first). The use of the two consecutive reactions has facilitated high conversions and a good control over the multiple reaction sites. In both examples, the CuAAC proceeded to quantitative conversion whereas the HDA cycloaddition proceeded to 94% conversion in the arm‐first approach and 81% in the core‐first approach.

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Local Viscosity in the Vicinity of a Wall Coated by Polymer Brush from Green–Kubo Relations
Authors: Dimitrov Dimitar I. , Milchev Andrey , Binder Kurt
Published: June 2008

When fluids are confined in slit pores between parallel walls, their static structures and their dynamical properties exhibit inhomogeneity in the z‐direction perpendicular to the wall. Of particular interest are local bulk viscosity ηb(z) and shear viscosity ηs(z). Here, we discuss an algorithm to estimate these quantities from Green–Kubo relations using equilibrium molecular dynamics. As an application example, a polymer brush (macromolecules end‐grafted to a substrate at z = 0) interacting with a solvent formed from point‐like particles is given.

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Quality of life in Parkinson's disease: The relative importance of the symptoms
Authors: Rahman Shibley , Griffin Harry J. , Quinn Niall P. , Jahanshahi Marjan
Published: June 2008

A body of literature now exists, which demonstrates that idiopathic Parkinson's disease (PD) has a major negative impact on quality of life (QoL), and that depression and cognitive impairment are among the main predictors of poor QoL in this disorder. Relatively little work has been done to assess the differential contribution of the specific symptoms of PD to QoL, which was the aim of this study. One hundred thirty patients with PD completed a booklet of questionnaires, which included the PDQ39 as a disease‐specific measure of QoL, a symptom checklist, a mobility checklist, as well as patient ratings of disease stage and disability. The results indicated that the contribution of physical, medication‐related, and cognitive/psychiatric symptoms to QoL can be significant. Sudden unpredictable on/off states, difficulty in dressing, difficulty in walking, falls, depression, and confusion were PD symptoms, which significantly influenced QoL scores. Among the mobility problems associated with PD, start hesitation, shuffling gait, freezing, festination, propulsion, and difficulty in turning had a significant effect on QoL scores. In addition to depression and anxiety, the major predictors of QoL were shuffling, difficulty turning, falls, difficulty in dressing, fatigue, confusion, autonomic disturbance particularly urinary incontinence, unpredictable on/off fluctuations, and sensory symptoms such as pain. The implications of these results for the medical management of PD are discussed. © 2007 Movement Disorder Society
Determination of sex and scrapie resistance genotype in preimplantation ovine embryos
Authors: Guignot Florence , Baril Gerard , Dupont Francis , Cognie Yves , Folch Jose , Alabart Jose Luis , Poulin Naty , Beckers Jean‐Francois , Bed'hom Bertrand , Babilliot Jean‐Marc , Mermillod Pascal
Published: June 2008

The aim of this study was to test the accuracy of genotype diagnosis after pre‐amplification of DNA extracted from biopsies obtained by microblade cutting of ovine embryos and to evaluate the viability of biopsied embryos after vitrification/warming and transfer to recipients. Sex and PrP genotypes were determined. Sex diagnosis was done by PCR amplification of ZFX/ZFY and SRY sequences after PEP‐PCR while PrP genotype determination was performed after specific pre‐amplification of specific target including codons 136, 154 and 171. Embryos were collected at Day 7 after oestrus. Blastocysts and expanded blastocysts were biopsied immediately after collection whereas compacted morulae were biopsied after 24 hr of in vitro culture. Eighty‐nine biopsied embryos were frozen by vitrification. Fresh and vitrified whole embryos were kept as control. DNA of biopsies was extracted and pre‐amplified. Sex diagnosis was efficient for 96.6% of biopsies and PrP genotyping was determined in 95.8% of codons. After embryo transfer, no significant difference was observed in lambing rate between biopsied, vitrified control and fresh embryos (54.5%, 60% and 66.6%, respectively). Embryo survival rate was not different between biopsied and whole vitrified embryos (P = 0.38). At birth, 96.7% of diagnosed sex and 95.4% of predetermined codons were correct. Lamb PrP profiles were in agreement with parental genotype. PEP‐PCR coupled with sex diagnosis and nested PCR coupled with PrP genotype predetermination are very accurate techniques to genotype ovine embryo before transfer. These original results allow planning of selection of resistant genotype to scrapie and sex of offspring before transfer of cryopreserved embryo. Mol. Reprod. Dev. 76: 183–190, 2009. © 2008 Wiley‐Liss, Inc.
Gonadotropin‐dependent regulation of the prostaglandin E2 receptor in equine preovulatory follicles during the ovulatory process in mares
Authors: Sayasith Khampoune , Bouchard Nadine , Doré Monique , Sirois Jean
Published: June 2008

The objectives of the study were to clone the primary structure of the prostaglandin E2 receptor subtype 2 (PTGER2) cDNA and to characterize its regulation in equine follicles during gonadotropin‐induced ovulation. Results from DNA isolation indicated that the equine PTGER2 cDNA encodes a predicted 353‐amino acid protein, which is highly similar (76–85%) to known mammalian homologues. The regulation of PTGER2 was studied by semi‐quantitative RT‐PCR/Southern blot using preparations of theca interna and mural granulosa cells isolated from equine follicles 0–39 hr post‐treatment with human chorionic gonadotropin (hCG). Results indicated that a significant increase of PTGER2 mRNA occurred at 24 and 39 hr post‐hCG in granulosa cells, and 30 and 33 hr post‐hCG in theca cells (P < 0.05). Immunohistochemical staining and immunoblotting performed on equine follicular samples showed a corresponding increase of PTGER2 protein in both cell types after treatment with hCG. Levels of PTGER2 mRNA were also high in uterus, thymus and spleen, but moderate to low in other tested tissues. In the ovary, the expression of PTGER4 mRNA was observed and predominantly occurred in granulosa cells, with highest abundance of transcripts observed at 12 and 39 hr post‐hCG. Thus, this study reports for the first time in mares that the ovulatory process is accompanied by the gonadotropin‐dependent up‐regulation of PTGER2 and PTGER4, which may in turn regulate PGE2‐mediated preovulatory effects. Mol. Reprod. Dev. 76: 191–201, 2009. © 2008 Wiley‐Liss, Inc.
Efficient production of nuclear transferred rat embryos by modified methods of reconstruction
Authors: Popova Elena , Bader Michael , Krivokharchenko Alexander
Published: June 2008

In this study we investigated spontaneous oocyte activation and developmental ability of rat embryos of the SD‐OFA substrain. We also tried to improve the somatic cell nuclear transfer (SCNT) technique in the rat by optimizing methods for the production of reconstructed embryos. About 20% of oocytes extruded the second polar body after culture for 3 hr in vitro and 84% of oocytes were at the MII stage. MG132 blocked spontaneous activation but decreased efficiency of parthenogenetic activation. Pronuclear formation was more efficient in strontium‐activated oocytes (66.1–80.9%) compared to roscovitine activation (24.1–54.5%). Survival rate after enucleation was significantly higher (89.4%) after slitting the zona pellucida and then pressing the oocyte with a holding pipette in medium without cytochalasin B (CB) compared to the conventional protocol using aspiration of the chromosomes after CB treatment (67.7%). Exposure of rat ova to UV light for 30 sec did not decrease their in vitro developmental capacity. Intracytoplasmic cumulus cell injection dramatically decreased survival rate of oocytes (42%). In contrast, 75.9% of oocytes could be successfully electrofused. Development to the 2‐cell stage was reduced after SCNT (24.6% compared 94.6% in controls) and none from 244 reconstructed embryos developed in vitro beyond this stage. After overnight in vitro culture, 74.4% of the SCNT embryos survived and 56.1% formed pronuclei. The pregnancy rate of 33 recipients after the transfer of 695 of these cloned embryos was, however, very low (18.2%) and only six implantation sites could be detected (0.9%) without any live fetuses and offspring. Mol. Reprod. Dev. 76: 208–216, 2009. © 2008 Wiley‐Liss, Inc.
Polymerisable Miniemulsions Using Rotor‐Stator Homogenisers
Authors: El‐Jaby Ula , Cunningham Michael , Enright Tom , McKenna Timothy F. L.
Published: June 2008

The use of a rotor‐stator mixer as a homogenisation device to make miniemulsion droplets with industrially pertinent solid contents was investigated. Methyl methacrylate/butyl acrylate (50:50 w/w ratio) miniemulsions with droplet diameters from 2 µm to 300 nm and polydispersity indices from 1.2 to 3.6 were used. Miniemulsions with three different mean droplet diameters (300, 400, 600 nm) were polymerised and the evolution of particle size was observed. When 300 nm droplets were polymerised they yielded particles of similar diameter to the original droplets, whereas particle coalescence of the growing particles with a loss of control over the particle size distribution was observed for the 400 and 600 nm droplets. The influence of costabiliser, agitation speed, solid content, colloidal protectors and surface coverage on the evolution of the droplet size and size distribution as well as on the evolution of the average particle size and its distribution were examined. It was observed that changing the above parameters had no impact on the evolution of the particle size, suggesting we have a very robust miniemulsion system.

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Quantitative methods, economics, and or models
Authors: Desai Anand
Published: June 2008

Training in quantitative methods is seen as essential for policy analysts, public administrators, and public managers if they are to make cogent and informed data‐based arguments. If our objective is to help students and future practitioners identify credible evidence, to make sense of that evidence, link it to their substantive knowledge, and thereby develop a defensible case for action, then this paper argues that our current approach to teaching methods is inappropriate. We need to take into consideration the learning styles and needs of our students in designing the delivery and content of our courses. Our current emphasis on teaching techniques needs to be replaced by an emphasis on teaching about the concepts underlying these tools and techniques. © 2008 by the Association for Public Policy Analysis and Management.
A strategic response to class size reduction: Combination classes and student achievement in California
Authors: Sims David
Published: June 2008

The California class size reduction program provided schools with cash rewards for K–3 classes of 20 or fewer students. I show how program rules made it possible for schools to save money by using mixed‐grade classes to meet class size reduction obligations while maintaining larger average class sizes. I also show that this smoothing of students across grades is associated with a significant test score gap for certain second and third grade students. My estimates suggest that class size reduction may lead to lower test scores for students placed in combination classes. Alternative explanations of teacher experience and credentialing changes cannot explain the test score pattern. This result spotlights both the underappreciated role of age heterogeneity in classroom learning and the difficulty of replicating the success of policy experiments in statewide reform. © 2008 by the Association for Public Policy Analysis and Management.
Causes of Urban Sprawl in the United States: Auto reliance as compared to natural evolution, flight from blight, and local revenue reliance
Authors: Wassmer Robert W.
Published: June 2008

This paper describes a statistical study of the contribution of theories previously offered by economists to explain differences in the degree of urban decentralization in the U.S. The focus is on a relative comparison of the influence of auto reliance. A regression analysis reveals that a 10 percent reduction in the percentage of households owning one or more autos would reduce the square mile size of an urban area by only 0.5 percent and raise its population density by only 0.7 percent. Factors falling under the categories of “natural evolution” and “flight from blight” exert a far greater magnitude of influence. For instance, a 10 percent reduction in per capita income would reduce the square mile size of an urban area by 11.4 percent and raise its population density by 10.1 percent, while a 10 percent decrease in the percentage central place(s) population poor would reduce the square mile size of an urban area by 2.6 percent and raise its population density by 1.7 percent. A significant increase in urban decentralization will require more than just reduced auto reliance. © 2008 by the Association for Public Policy Analysis and Management.
Do Job Corps performance measures track program impacts?
Authors: Schochet Peter Z. , Burghardt John A.
Published: June 2008

Since the 1993 Government Performance and Results Act, performance measurement systems based on short‐term program outcomes have been increasingly used to assess the effectiveness of federal programs. This paper examines the association between program performance measures and long‐term program impacts, using nine‐year follow‐up data from a recent large‐scale, national experimental evaluation of Job Corps, the nation's largest federal job training program for disadvantaged youths. Job Corps is an important test case because it uses a comprehensive performance system that is widely emulated. We find that impacts on key outcomes are not associated with measured center performance levels. Participants in higherperforming centers had better outcomes; however, the same pattern holds for comparable controls. Thus, the performance measurement system is not achieving the goal of ranking and rewarding centers on the basis of their ability to improve participant outcomes relative to what these outcomes would have been otherwise. © 2008 by the Association for Public Policy Analysis and Management.
Cognitive and non‐cognitive predictors of success in adult education programs: Evidence from experimental data with low‐income welfare recipients
Authors: Leininger Lindsey Jeanne , Kalil Ariel
Published: June 2008

Using data on approximately 2,000 low‐income welfare recipients in a three‐site random‐assignment intervention conducted in the early 1990s (the NEWWS), we examine the role of cognitive and non‐cognitive factors in moderating experimental impacts of an adult education training program for women who lacked a high school degree or GED at the time of random assignment. Both cognitive and noncognitive skills (in particular, locus of control) moderate treatment impacts. For the sample as a whole, assignment to an education‐focused program had a statistically significant (albeit modest) 8 percentage point impact on the probability of degree receipt. For those with low cognitive skills, virtually all of these program impacts were eliminated. However, non‐cognitive skills play a substantively important role such that women with high cognitive skills but low non‐cognitive skills are only half as likely to earn a degree as their counterparts with high skills of both types. © 2008 by the Association for Public Policy Analysis and Management.
A new and highly efficient formaldehyde absorbent of polyoxymethylene
Authors: Sun Tianju , Lai Yong , Ye Lin , Zhao Xiaowen
Published: June 2008

A new type of highly efficient formaldehyde (FA) absorbent of polyoxymethylene (POM), hexamethylenediamine–formaldehyde polycondensates (HF) was prepared by the condensation reaction of hexamethylenediamine (HA) and FA. The effects of the synthetic technique including FA/HA molar ratio, reaction temperature and dispersant dosage on the thermal stability of POM/HF were studied, and finely divided, slightly branched HF polycondensates with high molecular weight and relatively high processing thermal stability were obtained. The thermal stabilization effect of HF on POM was studied through the isothermal weight loss analysis, FA emission amount (FEA) measurement, and balance torque analysis, which showed that HF had better thermal stabilization effect on POM than the commonly used FA‐absorbent melamine (MA). In order to improve the crystallization performance and mechanical properties of POM, the nucleation effect of HF on POM was studied by means of polarized light microscopy (PLM), isothermal and nonisothermal differential scanning calorimetry (DSC), indicating that HF had remarkable nucleation effect on POM. The investigation of mechanical properties showed that the addition of HF could improve the impact toughness of POM to a certain degree. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis and characterization of copolymerizable one‐component type II photoinitiator
Authors: Xiao Pu , Shi Suqing , Nie Jun
Published: June 2008

A copolymerizable one‐component Type II photoinitiator (CMEBP), based on 4‐hydroxybenzophenone (HBP), epichlorohydrin, morpholine, and acryloyl chloride, was synthesized and its structure was confirmed by 1H‐NMR. The properties of CMEBP were investigated with UV spectroscopy and photo‐differential scanning calorimetry (photo‐DSC). The maximum of UV absorption red‐shifted significantly compared to benzophenone (BP). Photopolymerization results of tripropylene glycol diacrylate (TPGDA) indicated that CMEBP had larger maximum rate of polymerization than that of BP/triethanolamine (TEOHA) and HBP/triethylamine (TEA), larger final double bond conversion than that of HBP/TEA, but lower than that of BP/TEOHA. The rate of polymerization, final conversion increased and the induction period shortened with increase in CMEBP concentration. Copyright © 2008 John Wiley & Sons, Ltd.
Preparation of three‐dimensional structure controllable nanofibers by electrospinning
Authors: Zhang Jian‐Feng , Yang Dong‐Zhi , Nie Jun
Published: June 2008

The size of “bowl‐like” structures woven by nanofibers could be controlled by adjusting the distance from the nozzle to a modified collector and the voltage applied to the electrospinning device. More interestingly, the nanofibers in the side wall of the “bowl” could vibrate up and down with the changing of the voltage. This voltage‐induced vibration might have potential applications for bio‐mimic process and micro‐motor devices. Copyright © 2008 John Wiley & Sons, Ltd.