bluuebunny/crossref_metadata_2025 huggingface dataset:
A new method for mining of WWW access sequences
Authors: Oyanagi Shigeru , Kamiharako Masatoshi , Kubota Kazuto , Nakase Akihiko
Published: September 2007

Analysis of access sequences is an important technique in the mining of WWW access logs. The well‐known apriori algorithm is a typical method. A problem of this method is that the obtained relation between sequences is not reflected in the output. This paper proposes a new method of sequence analysis using matrix clustering. This method considers a binary matrix in which the sequences correspond to the rows and ordered pairs of pages correspond to the columns. The similarities between sequences are extracted as clusters in the matrix. Based on these clusters, super‐sequences, which are generalizations of similar sequences, can be generated. The proposed method is applied to real data and the results are evaluated. It is verified that the features of entire sequences can be extracted. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(10): 127–138, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20394
Synthesis, Characterization, Structures and Comparative Electrochemical Study of 2,4‐Bis(trimethylsilylethynyl)thiophene Coordinated Carbonylcobalt Units
Authors: Arnanz Avelina , Moreno Consuelo , Marcos María‐Luisa , González‐Velasco Jaime , Delgado Salomé
Published: September 2007

The reaction between 2,4‐dibromothiophene and trimethylsilylacetylene (TMSA) in the presence of Pd(PPh3)4, CuI and triethylamine gave rise to the formation of 2,4‐bis(trimethylsilylethynyl)thiophene (2,4T) and 4‐bromo‐2‐(trimethylsilylethynyl)thiophene (2,4T′). Complexes 1, 2, 3 or 1′ were obtained by direct reaction between Co2(CO)8 and 2,4T or 2,4T′, respectively. (Diphenylphosphanyl)methane‐substituted alkyne carbonyl complexes 4, 5, 6 and 2′ were prepared by substitution reaction of carbonyl ligands in the presence of Me3NO at the Co2(CO)6 units of 1, 2, 3 and 1′, respectively. Desilylation of the non‐metallated and metallated alkynes in 4, 5 and 6 occurred on treatment with KOH or tetrabutylammonium fluoride to give 7, 8 and 9. Crystals of 2′ suitable for single‐crystal X‐ray diffraction were grown, and the molecular structure of this compound is discussed. A comparative electrochemical study of these complexes in relation to analogous derivatives obtained from the organic ligand 2,5‐bis(trimethylsilylethynyl)thiophene (2,5T) is reported.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Electrochemical Synthesis of Mono‐ and Disubstituted Diiron Dithiolate Complexes as Models for the Active Site of Iron‐Only Hydrogenases
Authors: Morvan Didier , Capon Jean‐François , Gloaguen Frederic , Schollhammer Philippe , Talarmin Jean
Published: September 2007

[Fe2(S2C3H6)(CO)5{P(OMe)3}] (2) and [Fe2(S2C3H6)(CO)4{P(OMe)3}2] (3) were selectively prepared by the electrochemical reduction of [Fe2(S2C3H6)(CO)6] (1) in the presence of trimethyl phosphite ligand. Electrochemical data indicate a CO‐displacement reaction catalyzed by electron transfer. Complexes 2 and 3 were characterized by X‐ray crystallography, which shows that in the solid state, the trimethyl phosphite ligands lie in the apical configuration. NMR suggests that multiple isomers exist in solution. Both 2 and 3 exhibit a primary reduction step that involves two electrons. No stable hydride derivatives could be isolated by the reaction of 2 or 3 with strong acid. However, for both 2 and 3, proton reduction catalysis was detected at a potential less negative than that of the reduction of the diiron complex working as catalyst. The proposed mechanism involves a protonation of the diiron complex in the vicinity of the electrode, which is triggered by the more facile reduction of the protonated form (CE mechanism). The protonation and reduction steps are followed by a bimolecular reaction that regenerates the starting complex. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Using Chiral Ligand Substituents To Promote the Formation of Dinuclear, Double‐Stranded Iron, Manganese, and Zinc Mesocates
Authors: Reid Stuart D. , Wilson Claire , De Matteis Cristina I. , Love Jason B.
Published: September 2007

The synthesis and structures of dinuclear manganese, iron, and zinc complexes of chiral di‐iminodipyrromethane ligands (L) are reported. Schiff base condensation reactions between 5,5′‐diformyl‐2,2′‐dipyrromethane and the chiral amines (–)‐(R)‐CH(Me)tBu and (+)‐(R)‐CH(Me)Ph result in the straightforward synthesis of the new, chiral ligands H2L2 and H2L3, respectively. Salt elimination reactions between K2L and divalent Mn and Fe halides, and protonolysis reactions between ZnMe2 and H2L result in the formation of the new dinuclear complexes [M2(L)2]. Investigation of the structures of these compounds in solution and in the solid state reveal that chiral mesocates are formed for L = L2, whereas for L = L3, a racemic mixture of helicates is present.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Motile membrane protrusions regulate cell–cell adhesion and migration of olfactory ensheathing glia
Authors: Windus Louisa C. E. , Claxton Christina , Allen Chelsea L. , Key Brian , St John James A.
Published: September 2007

Olfactory ensheathing cells (OECs) are candidates for therapeutic approaches for neural regeneration due to their ability to assist axon regrowth in central nervous system lesion models. However, little is understood about the processes and mechanisms underlying migration of these cells. We report here that novel lamellipodial protrusions, termed lamellipodial waves, are integral to OEC migration. Time‐lapse imaging of migrating OECs revealed that these highly dynamic waves progress along the shaft of the cells and are crucial for mediating cell–cell adhesion. Without these waves, cell–cell adhesion does not occur and migrational rates decline. The activity of waves is modulated by both glial cell line‐derived neurotrophic factor and inhibitors of the JNK and SRC kinases. Furthermore, the activity of lamellipodial waves can be modulated by Mek1, independently of leading edge activity. The ability to selectively regulate cell migration via lamellipodial waves has implications for manipulating the migratory behavior of OECs during neural repair. © 2007 Wiley‐Liss, Inc.
A comparison of the performance of the EQ‐5D and SF‐6D for individuals aged ≥ 45 years
Authors: Barton Garry R. , Sach Tracey H. , Avery Anthony J. , Jenkinson Claire , Doherty Michael , Whynes David K. , Muir Kenneth R.
Published: September 2007

We sought to compare the performance of the EQ‐5D and SF‐6D with regard to the criteria of practicality, convergent validity, and construct validity, the level of agreement between the two measures was also assessed. Responses from 1865 individuals aged ≥ 45 years in one general practice were analysed. Of these, 93.1% completed the EQ‐5D, compared with 86.4% for the SF‐6D, where individuals who were older, female, of a lower occupational skill level, from an area of lower deprivation, or used prescribed medication were significantly less likely to complete the SF‐6D. The performance of both measures was comparable with regard to both convergent and construct validities, as both the EQ‐5D and SF‐6D scores were closely related to scores on the EuroQol visual analogue scale (VAS) (p<0.001) and able to discriminate between people who did and did not take: (i) analgesics and (ii) other prescribed medication. Despite EQ‐5D and SF‐6D scores being highly correlated (p<0.001), individuals who were healthier (according to the VAS) had higher mean scores on the EQ‐5D (p<0.001), whereas less healthy individuals had higher mean scores on the SF‐6D (individuals with knee pain, osteoarthritis, back pain, rheumatoid arthritis, and hip pain had significantly lower mean scores on the EQ‐5D, p<0.001). Copyright © 2007 John Wiley & Sons, Ltd.
Implementing quality control on a random number stream to improve a stochastic weather generator
Authors: Meyer Charles R. , Renschler Chris S. , Vining Roel C.
Published: September 2007

For decades, stochastic modellers have used computerized random number generators to produce random numeric sequences fitting a specified statistical distribution. Unfortunately, none of the random number generators we tested satisfactorily produced the target distribution. The result is generated distributions whose mean even diverges from the mean used to generate them, regardless of the length of run. Non‐uniform distributions from short sequences of random numbers are a major problem in stochastic climate generation, because truly uniform distributions are required to produce the intended climate parameter distributions. In order to ensure generation of a representative climate with the stochastic weather generator CLIGEN within a 30‐year run, we tested the climate output resulting from various random number generators. The resulting distributions of climate parameters showed significant departures from the target distributions in all cases. We traced this failure back to the uniform random number generators themselves. This paper proposes a quality control approach to select only those numbers that conform to the expected distribution being retained for subsequent use. The approach is based on goodness‐of‐fit analysis applied to the random numbers generated. Normally distributed deviates are further tested with confidence interval tests on their means and standard deviations. The positive effect of the new approach on the climate characteristics generated and the subsequent deterministic process‐based hydrology and soil erosion modelling are illustrated for four climatologically diverse sites. Copyright © 2007 John Wiley & Sons, Ltd.
Land management impacts on runoff sources in small Amazon watersheds
Authors: Chaves Joaquín , Neill Christopher , Germer Sonja , Neto Sérgio Gouveia , Krusche Alex , Elsenbeer Helmut
Published: September 2007

Forest clearing and conversion to cattle pasture in the lowland Amazon region has been linked to soil compaction and increased soil water storage, which combine to diminish soil infiltration, enhance quick lateral flows and increase the stream flow response to precipitation. Quantifying the importance of quick surficial flow in response to this land use change requires identification of water sources within catchments that contribute to stream flow. Using an end member mixing analysis approach, potential contributing sources of stream flow were evaluated during an entire rainy season in a forest and a pasture watershed drained by ephemeral‐to‐intermittent streams in the south‐western Amazon. Water yield was 17% of precipitation in the pasture and 0·8% of precipitation in the forest. During the early rainy season, throughfall, groundwater, and soil water contributed 79%, 18%, and 3%, respectively, to total forest stream flow. Over the entire rainy season, throughfall, groundwater, and shallow soil water provided 57%, 24%, and 19%, respectively, of stream flow. In the pasture watershed, overland flow dominated stream flow both in the early (67%) and late (57%) rainy season, with a mean contribution of 60% overland flow, 35% groundwater, and 5% soil water. The uncertainty associated with those estimates was studied using a Monte Carlo approach. In addition to large changes in total surface flow, marked differences were found in the proportions of total stream flow in the second half of the rainy season between the forest and pasture watershed. These results suggest that (1) there is great potential for alteration of the hydrological budgets of larger watersheds as the proportion of deforested land in the Amazon increases, and (2) as more rainfall is diverted into fast flowpaths to streams in established pastures, the potential to deliver water with higher solute concentrations generated by erosion or by bypassing sites of solute removal increases. Copyright © 2007 John Wiley & Sons, Ltd.
Downregulation of PAR‐4, a pro‐apoptotic gene, in pancreatic tumors harboring K‐ras mutation
Authors: Ahmed Mansoor M. , Sheldon David , Fruitwala Mushtaq A. , Venkatasubbarao Kolaparthi , Lee Eun Y. , Gupta Seema , Wood Craig , Mohiuddin Mohammed , Strodel William E.
Published: September 2007

Oncogenic ras is known to inhibit cell death and growth inhibitory genes and activate prosurvival genes. Proapoptotic gene PAR‐4, has been found to be downregulated by oncogenic ras. Since pancreatic tumors harbor a high incidence of K‐ras point mutations, we hypothesized that oncogenic K‐ras might influence the function and expression of PAR‐4. PAR‐4 expression levels were analyzed in 4 established pancreatic tumor cell lines, 10 normal pancreatic tissues, 44 frozen tumor tissues and 25 paraffin‐embedded pancreatic adenocarcinoma samples by Real Time RT‐PCR, Western blot analysis and immunohistochemistry. K‐ras mutational status was analyzed by allele‐specific oligonucleotide‐hybridization. Expression levels of PAR‐4 were correlated with the K‐ras mutational status and clinical characteristics. Further, modulation of endogenous PAR‐4 was tested by transiently expressing oncogenic ras in a wild‐type K‐ras pancreatic cancer cell line, BxPC‐3. Three cell lines with K‐ras mutations showed low levels of PAR‐4 when compared to a normal pancreatic tissue. Of 44 frozen tumors, 16 showed appreciable upregulation of Par mRNA and 27 showed significant downregulation of PAR‐4 mRNA when compared to normal pancreatic tissue and 1 had levels equivalent to normal pancreatic tissue. Of 25 paraffin‐embedded tumors, 9 showed downregulation of PAR‐4 protein and this downregulation of PAR‐4 correlated significantly with K‐ras mutational status (p < 0.00002). In addition, the presence of PAR‐4 mRNA or protein expression in pancreatic tumors correlated with prolonged survival. Transient overexpression of oncogenic ras in wild‐type K‐ras BxPC‐3 cells significantly downregulated the endogenous PAR‐4 protein levels and conferred accelerated growth. Thus, downregulation or loss of PAR‐4 expression by oncogenic ras may provide a selective survival advantage for pancreatic tumors, through inhibition of proapoptotic pathway mediated by PAR‐4. © 2007 Wiley‐Liss, Inc.
Tobacco smoking and cancer: A meta‐analysis
Authors: Gandini Sara , Botteri Edoardo , Iodice Simona , Boniol Mathieu , Lowenfels Albert B. , Maisonneuve Patrick , Boyle Peter
Published: September 2007

We conducted a systematic meta‐analysis of observational studies on cigarette smoking and cancer from 1961 to 2003. The aim was to quantify the risk for 13 cancer sites, recognized to be related to tobacco smoking by the International Agency for Research on Cancer (IARC), and to analyze the risk variation for each site in a systematic manner. We extracted data from 254 reports published between 1961 and 2003 (177 case‐control studies, 75 cohorts and 2 nested case‐control studies) included in the 2004 IARC Monograph on Tobacco Smoke and Involuntary Smoking. The analyses were carried out on 216 studies with reported estimates for ‘current’ and/or ‘former’ smokers. We performed sensitivity analysis, and looked for publication and other types of bias. Lung (RR = 8.96; 95% CI: 6.73–12.11), laryngeal (RR = 6.98; 95% CI: 3.14–15.52) and pharyngeal (RR = 6.76; 95% CI: 2.86–15.98) cancers presented the highest relative risks (RRs) for current smokers, followed by upper digestive tract (RR = 3.57; 95% CI: 2.63–4.84) and oral (RR = 3.43; 95% CI: 2.37–4.94) cancers. As expected, pooled RRs for respiratory cancers were greater than the pooled estimates for other sites. The analysis of heterogeneity showed that study type, gender and adjustment for confounding factors significantly influence the RRs estimates and the reliability of the studies. © 2007 Wiley‐Liss, Inc.
c‐Abl activates p38 MAPK independently of its tyrosine kinase activity: Implications in cisplatin‐based therapy
Authors: Galan‐Moya Eva M. , Hernandez‐Losa Javier , Aceves Luquero Clara I. , de la Cruz‐Morcillo Miguel A. , Ramírez‐Castillejo Carmen , Callejas‐Valera Juan L. , Arriaga Angel , Aranburo Antonio Fernandez , Cajal Santiago Ramón y , Silvio Gutkind J. , Sánchez‐Prieto Ricardo
Published: September 2007

Activation of p38 MAPK is a critical requisite for the therapeutics activity of the antitumor agent cisplatin. In this sense, a growing body of evidences supports the role of c‐Abl as a major determinant of p38 MAPK activation, especially in response to genotoxic stress when triggered by cisplatin. Here, we demonstrate that p38 MAPK activation in response to cisplatin does not require the tyrosine kinase activity of c‐Abl. Indeed, c‐Abl can activate the p38 MAPK signaling pathway by a mechanism that is independent of its tyrosine kinase activity, but that instead involves the ability of c‐Abl to increase the stability of MKK6. Similar results were obtained in chronic myeloid leukemia‐derived cell lines, in which a chimeric Bcr/Abl protein mimics the effects of c‐Abl overexpression on p38 MAPK activation. These findings may explain why a clinically used c‐Abl inhibitor, imatinib mesylate, fails to inhibit the p38 MAPK pathway alone or in combination with cisplatin, and provide evidence of a novel signaling mechanism in which these antitumor agents act. © 2007 Wiley‐Liss, Inc.
The activities of progesterone receptor isoform A and B are differentially modulated by their ligands in a gene‐selective manner
Authors: Leo Joyce C.L. , Lin Valerie C.L.
Published: September 2007

It is known that progesterone receptor (PR) isoform A (PR‐A) and isoform B (PR‐B) may mediate different effects of progesterone. The objective of this study was to determine if the functions of PR isoforms also vary in response to different PR modulators (PRM). The effects of 7 synthetic PRM were tested in MDA‐MB‐231 cells engineered to express PR‐A, PR‐B, or both PR isoforms. The effects of progesterone were similar in cells expressing PR‐A or PR‐B in which it inhibited growth and induced focal adhesion. On the other hand, synthetic PRM modulated the activity of the PR isoforms differently. RU486, CDB4124, 17α‐hydroxy CDB4124 and VA2914 exerted agonist activities on cell growth and adhesion via PR‐B. Via PR‐A, however, these compounds displayed agonist effect on cell growth but induced stellate morphology which was distinct from the agonist's effect. Their dual properties via PR‐A were also displayed at the gene expression level: the compounds acted as agonists on cell cycle genes but exhibited antagonistic effect on cell adhesion genes. Introduction of ERα by adenoviral vector to these cells did not change PR‐A or PR‐B mediated effect of PRM radically, but it causes significant cell rounding and modified the magnitudes of the responses to PRM. The findings suggest that the activities of PR isoforms may be modulated by different PRM through gene‐specific regulatory mechanisms. This raises an interesting possibility that PRM may be designed to be PR isoform and cellular pathway selective to achieve targeted therapy in breast cancer. © 2007 Wiley‐Liss, Inc.
Socio‐demographic determinants of participation in mammography screening
Authors: Euler‐Chelpin My von , Olsen Anne Helene , Njor Sisse , Vejborg Ilse , Schwartz Walter , Lynge Elsebeth
Published: September 2007

Our objective was to use individual data on socio‐demographic characteristics to identify predictors of participation in mammography screening and control to what extent they can explain the regional difference. We used data from mammography screening programmes in Copenhagen, 1991–1999, and Funen, 1993–2001, Denmark. Target groups were identified from the Population Register, screening data came from the health authority, and socio‐demographic data from Statistics Denmark. Included were women eligible for at least 3 screens. The crude RR of never use versus always use was 3.21 (95%CI, 3.07–3.35) for Copenhagen versus Funen, and the adjusted RR was 2.55 (95%CI, 2.43–2.67). The adjusted RR for never use among women without contact to a primary care physician was 2.50 (95% CI, 2.31–2.71) and 2.89 (95% CI, 2.66–3.14), and for women without dental care 2.94 (95% CI, 2.77–3.12) and 2.88 (95% CI, 2.68–3.10) for Copenhagen and Funen, respectively. Other important predictive factors for nonparticipation were not being married and not being Danish. In conclusion, to enhance participation in mammography screening programmes special attention needs to be given to women not using other primary health care services. All women in Copenhagen, irrespective of their socio‐demographic characteristics, had low participation. Screening programmes have to find ways to handle this urbanity factor. © 2007 Wiley‐Liss, Inc.
Beyond foreign‐body‐induced carcinogenesis: Impact of reactive oxygen species derived from inflammatory cells in tumorigenic conversion and tumor progression
Authors: Okada Futoshi
Published: September 2007

Foreign‐body‐induced carcinogenesis is a traditional, maybe old, way of understanding cancer development. A number of novel approaches are available today to elucidate cancer development. However, there are things we learn from the old, and thus I bring out some examples of various clinical cases and experimental models of foreign‐body‐induced tumorigenesis. What is notable is that the foreign bodies themselves are unrelated to each other, whereas commonly underlying in them is to induce inflammatory reaction, especially stromal proliferation, where those exogenous materials are incorporated and undigested. Such foreign‐body‐induced carcinogenesis is also recognized in the step of tumor progression, the final step of carcinogenesis that tumor cells acquire malignant phenotypes including metastatic properties. And the phenomenon is universally observed in several cell lines of different origins. In this review I would like to show the evidence that tumor development and progression are accelerated inevitably by inflammation caused from foreign bodies, and that reactive oxygen species derived from inflammatory cells are one of the most important genotoxic mediators to accelerate the process. © 2007 Wiley‐Liss, Inc.
Inflammation and cancer: An ancient link with novel potentials
Authors: Perwez Hussain S. , Harris Curtis C.
Published: September 2007

Infection and chronic inflammation contribute to about 1 in 4 of all cancer cases. Mediators of the inflammatory response, e.g., cytokines, free radicals, prostaglandins and growth factors, can induce genetic and epigenetic changes including point mutations in tumor suppressor genes, DNA methylation and post‐translational modifications, causing alterations in critical pathways responsible for maintaining the normal cellular homeostasis and leading to the development and progression of cancer. Recent discovery of an interaction between microRNAs and innate immunity during inflammation has further strengthened the association between inflammation and cancer. © 2007 Wiley‐Liss, Inc.
Introduction: Why are data on facilities important?
Authors: Watt Catherine E.
Published: September 2007

This chapter gives a broad overview of why data on facilities are important to universities and why institutional research offices are often involved with managing and using facilities data.
Where to start when previous facilities data are questionable
Authors: Watt Catherine E. , Higerd Thomas B. , Valcik Nicolas A.
Published: September 2007

This chapter discusses the techniques that three institutions used to determine what facilities data were accurate and then the processes that gathered new data on facilities and corrected data that were inaccurate or out of date.
Indirect costs and other uses of facilities data at institutions
Authors: Watt Catherine E. , Higerd Thomas B.
Published: September 2007

This chapter discusses how facilities data relate to research activities and funding for those types of activities in relation to indirect cost recovery efforts.
Axial specification in mice: Ten years of advances and controversies
Authors: Rivera‐Perez Jaime A.
Published: September 2007

The definitive axes of the mouse embryo can be unequivocally identified in embryos dissected at 5.5 days of gestation. However, how and when are these axes established remains an open question. At pre‐implantation stages, different approaches have been aimed at determining if events occurring in the zygote influence the geometrical arrangement of the blastocyst. An intense debate has focused on whether the mouse embryo is a pre‐patterned or a regulative structure. At post‐implantation stages, the efforts have been concentrated in understanding how extra‐embryonic tissues affect the formation of the primitive streak, the caudal marker of the anteroposterior axis. Here I summarize the last 10 years of research in this field. J. Cell. Physiol. 213:654–660. © 2007 Wiley‐Liss, Inc.
FVTD—integral equation hybrid for Maxwell's equations
Authors: Firsov Dmitry K. , LoVetri Joe
Published: September 2007

A new hybrid finite‐volume time‐domain integral equation (FVTD/IE) algorithm for the solution of Maxwell's Equations on unstructured meshes of arbitrary flat‐faceted volume elements is presented. A time‐domain IE‐based numerical algorithm is applied on the boundary of the computational domain to determine the incoming fluxes for the boundary facets of the mesh. This method is a global grid‐truncation technique similar to the method previously introduced for the finite‐difference time‐domain scheme by Ziolkowski et al. The three main advantages of this IE truncation method are that (1) it allows geometrical objects to be located (almost) arbitrarily close to the mesh boundaries without compromising the physics of the problem, (2) it couples the physics of unconnected meshes so that distant scatterers can be surrounded by their own local mesh, thus reducing total mesh size, and (3) the same IE formulation can be used to compute electromagnetic field values at points outside the mesh. Currently, the main disadvantage is that an acceleration scheme for performing the IE update, which requires integrating field components on an interior surface at a retarded time, is not available. Computational results are presented for the scattering from a perfectly electrical conducting sphere and compared numerically with the analytic time‐domain solution as well as the solution obtained using a large spherical outer mesh boundary with local absorbing boundary conditions. Results are excellent and show almost no reflections from the mesh boundary even when the observation point is located close to the corner of the cubically shaped outside mesh boundary. Results are also presented and validated for the scattering from two objects that are contained inside their own unconnected meshes. Copyright © 2007 John Wiley & Sons, Ltd.
Growth‐compromised HSV‐2 vector ΔRR protects from N‐methyl‐D‐aspartate‐induced neuronal degeneration through redundant activation of the MEK/ERK and PI3‐K/Akt survival pathways, either one of which overrides apoptotic cascades
Authors: Laing Jennifer M. , Golembewski Erin K. , Wales Samantha Q. , Liu Juan , Jafri M. Samir , Yarowsky Paul J. , Aurelian Laure
Published: September 2007

We have previously shown that intrastriatal injection of ΔRR, the growth‐compromised herpes simplex virus type 2 (HSV‐2) vector for the antiapoptotic protein ICP10PK, prevents apoptosis caused by the excitotoxin N‐methyl‐D‐aspartate (NMDA) in a mouse model of glutamatergic neuronal cell death (Golembewski et al. [2007] Exp. Neurol. 203:381–393). Because apoptosis regulation is stimulus and cell type specific, our studies were designed to examine the mechanism of ΔRR‐mediated neuroprotection in striatal neurons. Organotypic striatal cultures (OSC) that retain much of the synaptic circuitry of the intact striatum were infected with ΔRR or a growth‐compromised HSV‐2 vector that lacks ICP10PK (ΔPK) and examined for neuroprotection‐associated signaling. The mutated ICP10 proteins (p175 and p95) were expressed in 70–80% of neurons from ΔRR‐ and ΔPK‐infected cultures, respectively, as determined by double‐immunofluorescent staining with antibodies to ICP10 and NeuN or GAD65. ΔRR‐ but not ΔPK‐treated OSC were protected from NMDA‐induced apoptosis, as verified by ethidium homodimer staining, TUNEL, caspase‐3 activation, and poly(AD‐ribose) polymerase (PARP) cleavage. Neuroprotection was through ICP10PK‐mediated activation of the survival pathways MEK/ERK and PI3‐K/Akt, up‐regulation of the antiapoptotic proteins Bag‐1 and Bcl‐2, and phosphorylation (inactivation) of the proapoptotic protein Bad. It was blocked by the MEK inhibitor U0126 or the PI3‐K inhibitor LY294002, suggesting that either pathway can prevent NMDA‐induced apoptosis. The data indicate that ΔRR‐delivered ICP10PK stimulates redundant survival pathways that override proapoptotic cascades. ΔRR is a promising gene therapy platform against glutamatergic cell death. © 2007 Wiley‐Liss, Inc.
Low‐dose morphine induces hyperalgesia through activation of Gαs, protein kinase C, and l‐type Ca2+ channels in rats
Authors: Esmaeili‐Mahani Saeed , Shimokawa Noriaki , Javan Mohammad , Maghsoudi Nader , Motamedi Fereshteh , Koibuchi Noriyuki , Ahmadiani Abolhasan
Published: September 2007

Opioids can induce analgesia and also hyperalgesia in humans and in animals. It has been shown that systemic administration of morphine induced a hyperalgesic response at an extremely low dose. However, the exact mechanism(s) underlying opioid‐induced hyperalgesia has not yet been clarified. Here, we have investigated cellular events involved in low‐dose morphine hyperalgesia in male Wistar rats. The data showed that morphine (0.01 μg i.t.) could elicit hyperalgesia as assessed by the tail‐flick test. Gαs mRNA and protein levels increased significantly following exposure to the hyperalgesic dose of morphine. Furthermore, morphine at an analgesic dose (20 μg i.t.) significantly decreased cAMP levels in the dorsal half of the lumbar spinal cord, whereas the tissue cAMP levels were not affected by morphine treatment at a hyperalgesic dose. Intrathecal administration of nifedipine, an L‐type calcium channel blocker, antagonized the hyperalgesia induced by the low‐dose of morphine. Furthermore, pretreatment with the selective protein kinase C (PKC) inhibitor chelerytrine resulted in prevention of the morphine‐induced hyperalgesia. KT 5720, a specific inhibitor of protein kinase A (PKA), did not show any effect on low‐dose morphine‐induced hyperalgesia. These results indicate a role for Gαs, the PLC‐PKC pathway, and L‐type calcium channels in intrathecal morphine‐induced hyperalgesia in rats. Activation of ordinary Gαs signaling through cAMP levels did not appear to play a major role in the induction of hyperalgesia by low‐dose of morphine. © 2007 Wiley‐Liss, Inc.
Aquaporin‐4 water channels in enteric neurons
Authors: Thi Mia M. , Spray David C. , Hanani Menachem
Published: September 2007

Aquaporin‐4 is a water channel predominantly found in astrocytes in the central nervous system and is believed to play a critical role in the formation and maintenance of the blood–brain barrier and in water secretion from the brain. As enteric glial cells were found to share several similarities with astrocytes, we hypothesized that enteric glia might also contain aquaporin‐4. We used immunohistochemistry to identify aquaporin‐4 in the myenteric and submucosal plexuses of the mouse and the rat colon. We found that subpopulations of neurons in both enteric plexuses were positively labeled for human aquaporin‐4. Double staining of the enteric ganglia with antibodies to the neuronal marker neurofilament–heavy chain 100 and to aquaporin‐4 showed that a minority of myenteric neurons were aquaporin‐4 positive (about 12% in the mouse and 13% in the rat). In contrast, in the submucosal plexus significant numbers of neurons were positive for aquaporin‐4 (about 79% in both the mouse and the rat). Double labeling for aquaporin‐4 and for the glial marker glial fibrillary acidic protein verified that glial cells were not immunoreactive to aquaporin‐4. We further confirmed our findings with additional aquaporin‐4 antibodies and Western blot analysis. We found that, in addition to expressing aquaporin‐4, the myenteric plexus and, to a greater extent, the submucosal plexus both expressed aquaporin‐1. We conclude that neurons rather than glial cells contain aquaporin‐4 in the colonic enteric plexuses. It is known that submucosal neurons control transport processes in the intestinal mucosa, and the high percentage of aquaporin‐4‐postive submucosal neurons suggests that aquaporin‐4 contributes to this function. © 2007 Wiley‐Liss, Inc.
Pharmacological inhibition of GSK‐3 is not strictly correlated with a decrease in tyrosine phosphorylation of residues 216/279
Authors: Simón D. , Benitez M. J. , Gimenez‐Cassina A. , Garrido J. J. , Bhat R. V. , Díaz‐Nido J. , Wandosell F.
Published: September 2007

Recent evidence suggests that intramolecular autophosphorylation is responsible for the tyrosine phosphorylation (pY) of residues 279 or 216 of glycogen synthase kinase–3 (GSK‐3α or β), an event that appears to play an important role in regulating this kinase. This provocative hypothesis was based on the capacity of certain nonselective GSK‐3 inhibitors to alter both the activity of GSK‐3 and its pY. Inhibitors of GSK‐3 are not always capable of preventing this tyrosine phosphorylation, which may require an extended period of time. For example, although lithium chloride inhibits GSK‐3 activity, this inhibition does not alter its pY content. Furthermore, even when GSK‐3 activity is impaired, GSK‐3 pY can still be modified by physiological or pharmacological agents. Taken together, these data indicate that GSK‐3 kinase activity is not necessarily correlated with the extent of GSK‐3 pY. We hypothesized that some as‐yet‐unidentified tyrosine kinases and phosphatases may also regulate this kinase. © 2007 Wiley‐Liss, Inc.
Raman spectroscopy of halogen‐containing carbonates
Authors: Frost Ray L. , Dickfos Marilla J.
Published: September 2007

Raman spectroscopy complemented with infrared spectroscopy has been used to study a series of selected natural halogenated carbonates from different origins, including bastnasite, parisite and northupite. The position of CO32− symmetric stretching vibration varies with the mineral composition. An additional band for northupite at 1107 cm−1 is observed. Raman spectra of bastnasite, parisite and northupite show single bands at 1433, 1420 and 1554 cm−1, respectively, assigned to the ν3 (CO3)2− asymmetric stretching mode. The observation of additional Raman bands for the ν3 modes for some halogenated carbonates is significant in that it shows distortion of the CaO6 octahedron. No ν2 Raman bending modes are observed for these minerals. The band is observed in the infrared spectra, and multiple ν2 modes at 844 and 867 cm−1 are observed for parisite. A single intense infrared band is found at 879 cm−1 for northupite. Raman bands are observed forthe carbonate ν4 in‐phase bending modes at 722 cm−1 for bastnasite, 736 and 684 cm−1 for parisite and 714 cm−1 for northupite. Multiple bands are observed in the OH stretching region for selected bastansites and parisites, indicating the presence of water and OH units in the mineral structure. The presence of such bands brings into question the actual formula of these halogenated carbonate minerals. Copyright © 2007 John Wiley & Sons, Ltd.
Dissociation of C6F5SO3Li in two organic solvents with different dielectric constants: a Raman spectroscopic study
Authors: Hirankumar G. , Iojoiu C. , Alloin F. , Sanchez J. Y. , Pagnier T.
Published: September 2007

Organic solutions of lithium pentafluorobenzene sulfonate (C6F5SO3Li) with varying molalities in N,N‐dimethyl formamide (DMF) and triethyleneglycol dimethylether (triglyme) were investigated by Raman spectroscopy. Spectral decomposition in the νs(SO3) stretching region showed bands characteristic of free anions, ion pairs and various aggregates. The relative fraction of each species has been followed as a function of salt molality. In DMF, free anions dominate, while in triglyme ion pairs dominate, in accordance with the solvent dielectric constant. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and Raman spectroscopic characterisation of hydrotalcite with CO32− and VO3− anions in the interlayer
Authors: Palmer Sara J. , Nguyen Tai , Frost Ray L.
Published: September 2007

Infrared and Raman spectroscopy were used to characterise synthetic mixed carbonate and vanadate hydrotalcites of formula Mg6Al2(OH)16(CO3)2−, (VO4)3−·4H2 O. The spectra were used to assess the molecular assembly of the cations and anions in the hydrotalcite structure. The spectra may be conveniently subdivided into spectral features based on (1) the carbonate anion (2) the hydroxyl units and (3) water units. Bands were assigned to the hydroxyl stretching vibrations of water. Three types of carbonate anions were identified: (1) carbonate hydrogen‐bonded to water in the interlayer, (2) carbonate hydrogen‐bonded to the hydrotalcite hydroxyl surface and (3) free carbonate anions. It is proposed that the water is highly structured in the hydrotalcite, as it is hydrogen‐bonded to both the carbonate and the hydroxyl surface. The spectra were used to assess the contamination of carbonate in an open reacting vessel in the synthesis of vanadate hydrotalcites of formula Mg6Al2(OH)16(CO3)2−, (VO4)3−·4H2 O. Bands have been assigned to vanadate anions in the infrared and Raman spectra associated with VO bonds. Copyright © 2007 John Wiley & Sons, Ltd.
Raman spectroscopic studies of ZnSe/GaAs interfaces
Authors: El‐Brolossy T. A. , Talaat H.
Published: September 2007

ZnSe/semi‐insulating GaAs interfaces were studied by observing photogenerated plasmon–LO (PPL) coupled modes by nonresonant micro‐Raman spectroscopy. The effect of the carriers generated by the focused laser beam was investigated for a series of different thicknesses of ZnSe epitaxial layers. The PPL mode in GaAs was observed in the micro‐Raman spectra for all samples, but with different magnitude. The plasma is believed to be an electron gas as a result of the negative nature of the interfacial region that contains predominantly hole traps. The free carrier concentration is estimated to be > 1018 cm−3 and their lifetime ∼0.1 ns. This relatively long lifetime suggests that the ZnSe/GaAs interface has to be of high structural quality leading to a low recombination velocity. ZnSe/GaAs heterostructures of less crystalline quality (as determined by resonant Raman measurements) shows the effect of photogenerated carriers only to lesser extent. Copyright © 2007 John Wiley & Sons, Ltd.
Raman spectroscopic study of the multi‐anion uranyl mineral schroeckingerite
Authors: Frost Ray L. , Čejka Jiří , Ayoko Godwin A. , Dickfos Marilla J.
Published: September 2007

Raman spectroscopy complemented with infrared (IR) spectroscopy has been used to study the mineral schroeckingerite. The mineral is a multi‐anion mineral and has (UO2)2+, (SO4)2− and (CO3)2− units in its structure, and bands attributed to these vibrating units are readily identified in the Raman spectra. Symmetric stretching modes at 815, 983 and 1092 cm−1 are assigned to (UO2)2+, (SO4)2− and (CO3)2− units, respectively. The antisymmetric stretching modes of (UO2)2+, (SO4)2− are not observed in the Raman spectra but may be readily observed in the IR spectrum at 898 and 1180 cm−1. The antisymmetric stretching mode of (CO3)2− is observed in the Raman spectrum at 1374 cm−1, as is also the ν4 (CO3)2− bending modes at 742 and 707 cm−1. No ν2 (CO3)2− bending modes are observed in the Raman spectrum of schroeckingerite. All the spectroscopic evidence points to a highly ordered structure of this mineral. Copyright © 2007 John Wiley & Sons, Ltd.
Application of monolithic supports to online extraction and LC‐MS analysis of benzodiazepines in whole blood samples
Authors: Bugey Aurélie , Staub Christian
Published: September 2007

A column‐switching (CS) LC‐MS method allowing high‐speed determination of benzodiazepines (BZDs) in whole blood is presented. After protein precipitation with ACN followed by evaporation and reconstitution with the loading mobile phase, the online sample clean‐up was carried out using a CS device. Two extractive precolumns were evaluated: a conventional restricted access material (RAM) sorbent and a monolithic silica support. Separation was achieved using a ChromolithTM Performance RP‐18e (100 mm×4.6 mm id) monolithic silica column, and detection was performed by atmospheric pressure chemical ionization (APCI) MS. The method with both supports has been fully validated according to an accuracy profile approach. Finally, the monolithic silica column, demonstrating better validation data and a higher robustness than the RAM sorbent, was used for the analysis of several real forensic cases.
Numerical evaluation of pressure from experimentally measured film thickness in EHL point contact
Authors: Vaverka Michal , Vrbka Martin , Poliščuk Radek , Křupka Ivan , Hartl Martin
Published: September 2007

This paper is concerned with elastohydrodynamic lubrication, especially the determination of lubricant film thickness and contact pressure within a point contact of friction surfaces of machine parts. A new solution technique for numerical determination of contact pressure is introduced. The direct measurement of contact pressure is very difficult. Hence, input data of lubricant film thickness obtained from the experiment based on colorimetric interferometry are used for the calculation of pressure using the inverse elasticity theory. The algorithm is enhanced by convolution in order to increase calculation speed. The approach described in this contribution gives reliable results on smooth contact and in the future, it will be extended to enable the study of contact of friction surfaces with asperities. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis of Polar and Non‐Polar Nano‐Corundum and Uses for Aluminium Carboxylate Hybrid Nanocomposites with Enhanced Surface Mechanical and Viscoelastic Properties
Authors: Gläsel Hans‐Jürgen , Hartmann Eberhard , Mehnert Reiner , Wennrich Luise , Prager‐Duschke Andrea , Khalil Hazem , Hallmeier Karl Heinz , Makhova Ludmila , Thieroff Christoph , Buchmeiser Michael R.
Published: September 2007

Amorphous aluminium carboxylate nanoparticles were checked for their potential as precursors for nano‐corundum powders prepared by a high‐temperature conversion process. Exemplifying x‐ray photoelectron spectroscopy studies of the aluminium carboxylate nanoparticles with polar and non‐polar ligands showed that, during the course of the high‐temperature treatment, specific features of the ultrafine organo‐aluminium powders such as polarity/non‐polarity and concomitant hydrophilic/hydrophobic properties were preserved. The resulting nano‐corundum powders were in turn identified as positive synergists for the enforcement of radiation‐cured aluminium carboxylate/acrylate coatings. The simultaneous (optional) use of micro‐corundum particles yielded polymer hybrid coatings. In comparison to acrylate‐based organo‐aluminium nanocomposites, polymeric hybrid coatings revealed significantly improved surface mechanical and viscoelastic properties. In addition to acrylate coatings, other polar and even non‐polar bulk polymers were subject to nano/micro modification using polar and non‐polar nano‐corundum powders, respectively.

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Molecularly Imprinted Nanofiber Membranes from Carboxylated Polysulfone by Electrospray Deposition
Authors: Yoshikawa Masakazu , Nakai Koji , Matsumoto Hidetoshi , Tanioka Akihiko , Guiver Michael D. , Robertson Gilles P.
Published: September 2007

It is demonstrated that polymeric materials can be directly converted into molecular (chiral) recognition nanofiber membranes by simultaneously applying an electrospray deposition and an alternative molecular imprinting during the membrane preparation process. Polysulfone with a degree of substitution of 0.88 was adopted as the candidate polymeric material for molecularly imprinted nanofiber membranes. Molecularly imprinted nanofiber membranes imprinted by Z‐D‐Glu recognize the D‐isomer in preference to the corresponding L‐isomer and vice versa. The amino acid preferentially incorporated into the membrane is selectively permeated through the membrane by using a concentration gradient as a driving force for membrane transport.

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One‐Pot Synthesis of Well‐Defined Amphiphilic and Adaptative Block Copolymers via Versatile Combination of “Click” Chemistry and ATRP
Authors: Mespouille Laetitia , Vachaudez Magali , Suriano Fabian , Gerbaux Pascal , Coulembier Olivier , Degée Philippe , Flammang Robert , Dubois Philippe
Published: September 2007

Well‐defined amphiphilic PCL‐b‐PDMAEMA block copolymers were successfully synthesized by a combination of ATRP and “click” chemistry following either a commutative two‐step procedure or a straightforward one‐pot process using CuBr · 3Bpy as the sole catalyst. Compared to the traditional coupling method, combining ATRP and click chemistry even in a “one‐pot” process allows the preparation of PCL‐b‐PDMAEMA diblock copolymers characterized by a narrow molecular weight distribution and quantitative conversion of azides and alkynes into triazole functions. Moreover, the amphiphilic character of these copolymers was demonstrated by surface tension measurements and critical micellization concentration was calculated.

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A New Poly(2,7‐Dibenzosilole) Derivative in Polymer Solar Cells
Authors: Boudreault Pierre‐Luc T. , Michaud Alexandre , Leclerc Mario
Published: September 2007

A new soluble conjugated copolymer based on 2,7‐dibenzosilole and 4,7‐dithien‐2‐yl‐2,1,3‐benzothiadiazole units has been synthesized (PBSDTBT). Bulk heterojunction solar cell devices are fabricated using this material as the donor and [6,6]‐phenyl‐C61 butyric acid methyl ester (PCBM) as the acceptor. The power conversion efficiency is 1.6% under AM1.5 illumination. This material also shows a good VOC (0.97 V). The results are quite promising considering the relatively large bandgap (1.9 eV) of this polymer.

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Thermal Degradation Kinetics of Nylon 66: Experimental Study and Comparison with Model Predictions
Authors: Schaffer Mark A. , McAuley Kim B. , Marchildon E. Keith , Cunningham Michael F.
Published: September 2007

An experimental investigation of nonoxidative thermal degradation kinetics of nylon 66 melt under high temperature (280–300 °C) and low water content (0.02–0.14 wt.‐%) conditions is presented. Experimental data for the time evolution of polymer end‐group concentrations and degradation‐product generation rates were compared with the predictions of the only published kinetic model. The omitted influence of water content is a plausible partial explanation for the considerable discrepancy between model predictions and some data. Several previously unreported or unquantified degradation products were identified and measured. Potential additional reactions to account for these results in future kinetic models are proposed.

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